Mitigating effects of L-selenomethionine on low-dose iron ion radiation-induced changes in gene expression associated with cellular stress.

PubMed

Nuth, Manunya; Kennedy, Ann R

2013-07-01

Ionizing radiation associated with highly energetic and charged heavy (HZE) particles poses a danger to astronauts during space travel. The aim of the present study was to evaluate the patterns of gene expression associated with cellular exposure to low-dose iron ion irradiation, in the presence and absence of L-selenomethionine (SeM). Human thyroid epithelial cells (HTori-3) were exposed to low-dose iron ion (1 GeV/n) irradiation at 10 or 20 cGy with or without SeM pretreatment. The cells were harvested 6 and 16 h post-irradiation and analyzed by the Affymetrix U133Av2 gene chip arrays. Genes exhibiting a 1.5-fold expression cut-off and 5% false discovery rate (FDR) were considered statistically significant and subsequently analyzed using the Database for Annotation, Visualization and Integrated Discovery (DAVID) for pathway analysis. Representative genes were further validated by real-time RT-PCR. Even at low doses of radiation from iron ions, global genome profiling of the irradiated cells revealed the upregulation of genes associated with the activation of stress-related signaling pathways (ubiquitin-mediated proteolysis, p53 signaling, cell cycle and apoptosis), which occurred in a dose-dependent manner. A 24-h pretreatment with SeM was shown to reduce the radiation effects by mitigating stress-related signaling pathways and downregulating certain genes associated with cell adhesion. The mechanism by which SeM prevents radiation-induced transformation in vitro may involve the suppression of the expression of genes associated with stress-related signaling and certain cell adhesion events.

Fate of Antibiotic Resistant Bacteria and Genes during Wastewater Chlorination: Implication for Antibiotic Resistance Control

PubMed Central

Yuan, Qing-Bin; Guo, Mei-Ting; Yang, Jian

2015-01-01

This study investigated fates of nine antibiotic-resistant bacteria as well as two series of antibiotic resistance genes in wastewater treated by various doses of chlorine (0, 15, 30, 60, 150 and 300 mg Cl2 min/L). The results indicated that chlorination was effective in inactivating antibiotic-resistant bacteria. Most bacteria were inactivated completely at the lowest dose (15 mg Cl2 min/L). By comparison, sulfadiazine- and erythromycin-resistant bacteria exhibited tolerance to low chlorine dose (up to 60 mg Cl2 min/L). However, quantitative real-time PCRs revealed that chlorination decreased limited erythromycin or tetracycline resistance genes, with the removal levels of overall erythromycin and tetracycline resistance genes at 0.42 ± 0.12 log and 0.10 ± 0.02 log, respectively. About 40% of erythromycin-resistance genes and 80% of tetracycline resistance genes could not be removed by chlorination. Chlorination was considered not effective in controlling antimicrobial resistance. More concern needs to be paid to the potential risk of antibiotic resistance genes in the wastewater after chlorination. PMID:25738838

The effects of different doses of IGF-1 on cartilage and subchondral bone during the repair of full-thickness articular cartilage defects in rabbits.

PubMed

Zhang, Z; Li, L; Yang, W; Cao, Y; Shi, Y; Li, X; Zhang, Q

2017-02-01

To investigate the effects of different doses of insulin-like growth factor 1 (IGF-1) on the cartilage layer and subchondral bone (SB) during repair of full-thickness articular cartilage (AC) defects. IGF-1-loaded collagen membrane was implanted into full-thickness AC defects in rabbits. The effects of two different doses of IGF-1 on cartilage layer and SB adjacent to the defect, the cartilage structure, formation and integration, and the new SB formation were evaluated at the 1st, 4th and 8th week postoperation. Meanwhile, after 1 week treatment, the relative mRNA expressions in tissues adjacent to the defect, including cartilage and SB were determined by quantitative real-time RT-PCR (qRT-PCR), respectively. Different doses of IGF-1 induced different gene expression profiles in tissues adjacent to the defect and resulted in different repair outcomes. Particularly, at high dose IGF-1 aided cell survival, regulated the gene expressions in cartilage layer adjacent defect and altered ECM composition more effectively, improved the formation and integrity of neo-cartilage. While, at low dose IGF-1 regulated the gene expressions in SB more efficaciously and subsequently promoted the SB remodeling and reconstruction. Different doses of IGF-1 induced different responses of cartilage or SB during the repair of full-thickness AC defects. Particularly, high dose of IGF-1 was more beneficial to the neo-cartilage formation and integration, while low dose of it was more effective for the SB formation. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Dynamic changes in prefrontal cortex gene expression following lysergic acid diethylamide administration.

PubMed

Nichols, Charles D; Garcia, Efrain E; Sanders-Bush, Elaine

2003-03-17

Lysergic acid diethylamide (LSD) is a psychoactive drug that transiently alters human perception, behavior, and mood at extremely low doses. Certain aspects of the behavior elicited by acute doses of LSD closely resemble symptoms of mental disorders such as schizophrenia. Characterizing gene expression profiles after LSD will be important for understanding how it alters behavior, and will lead to novel insights into disorders, such as schizophrenia, whose behavioral symptoms resemble the temporary effects of hallucinogenic drugs. We previously identified a small collection of genes within the rat prefrontal cortex that respond to LSD. Many of the products of these genes are involved in the process of synaptic plasticity. In the current report, we present a detailed analysis of the expression of these genes within the brain using RNase protection analysis. We find that the gene response to LSD is quite dynamic. The expression of some genes increases rapidly and decreases rapidly, while other genes change more gradually. Dose-response studies show two classes of expression; gene expression maximally stimulated at lower doses, versus gene expression that continues to rise at the higher doses. The role of the 5-HT(1A) and 5-HT(2A) receptor in mediating the increases in gene expression was examined in a series of experiments using receptor specific antagonists. Most expression increases were due to activation of the 5-HT(2A) receptor, however expression of two genes had neither a 5-HT(1A) nor a 5-HT(2A) receptor component.

Effect of low dose of vinclozolin on reproductive tract development and sperm parameters in CD1 outbred mice.

PubMed

Elzeinova, Fatima; Novakova, Vendula; Buckiova, Daniela; Kubatova, Alena; Peknicova, Jana

2008-01-01

The effect of a low dose of vinclozolin within the development of the reproductive tract during gestation (VIN-GD 15-22) and puberty (VIN-PND 23-44) in CD1 mice was tested. We found a decrease in the anogenital distance, prostate weight and pathology of testes in both experimental groups. Sperm counts decreased to 46% (VIN-GD) and to 81% (VIN-PND), and also the acrosomal state (evaluated by antiacrosomal antibody) decreased in both groups to 89% in comparison to the control group (100%). Sperm head abnormalities increased by approximately 18% and 13%, respectively. In this connection, the expression of some genes was changed (arosome-related gene (Acr), apoptosis related genes (p53, p21)). In conclusion, a low dose of vinclozolin affected the reproductive tract, sperm parameters and expression of selected genes in both experimental groups.

IL-33 stimulates expression of the GPR84 (EX33) fatty acid receptor gene and of cytokine and chemokine genes in human adipocytes.

PubMed

Zaibi, Mohamed S; Kępczyńska, Małgorzata A; Harikumar, Parvathy; Alomar, Suliman Y; Trayhurn, Paul

2018-05-15

Expression of GPCR fatty acid sensor/receptor genes in adipocytes is modulated by inflammatory mediators, particularly IL-1β. In this study we examined whether the IL-1 gene superfamily member, IL-33, also regulates expression of the fatty acid receptor genes in adipocytes. Human fat cells, differentiated from preadipocytes, were incubated with IL-33 at three different dose levels for 3 or 24 h and mRNA measured by qPCR. Treatment with IL-33 induced a dose-dependent increase in GPR84 mRNA at 3 h, the level with the highest dose being 13.7-fold greater than in controls. Stimulation of GPR84 expression was transitory; the mRNA level was not elevated at 24 h. In contrast to GPR84, IL-33 had no effect on GPR120 expression. IL-33 markedly stimulated expression of the IL1B, CCL2, IL6, CXCL2 and CSF3 genes, but there was no effect on ADIPOQ expression. The largest effect was on CSF3, the mRNA level of which increased 183-fold over controls at 3 h with the highest dose of IL-33; there was a parallel increase in the secretion of G-CSF protein into the medium. It is concluded that in human adipocytes IL-33, which is synthesised in adipose tissue, has a strong stimulatory effect on the expression of cytokine and chemokine genes, particularly CSF3, and on the expression of GPR84, a pro-inflammatory fatty acid receptor. Copyright © 2018 Elsevier Ltd. All rights reserved.

Concordance of transcriptional and apical benchmark dose levels for conazole-ind uced liver effects in mice

EPA Science Inventory

The ability to anchor chemical class-based gene expression changes to phenotypic lesions and to describe these changes as a function of dose and time can inform mode of action and improve quantitative risk assessment. Previous research identified a 330-gene cluster commonly resp...

Effects of Phonation Time and Magnitude Dose on Vocal Fold Epithelial Genes, Barrier Integrity, and Function

PubMed Central

Kojima, Tsuyoshi; Valenzuela, Carla V.; Novaleski, Carolyn K.; Van Deusen, Mark; Mitchell, Joshua R.; Garrett, C. Gaelyn; Sivasankar, M. Preeti; Rousseau, Bernard

2014-01-01

Objective To investigate the effects of increasing time and magnitude doses of vibration exposure on transcription of the vocal fold's junctional proteins, structural alterations, and functional tissue outcomes. Study Design Animal study. Methods 100 New Zealand White breeder rabbits were studied. Dependent variables were measured in response to increasing time doses (30, 60, or 120 minutes) and magnitude doses (control, modal intensity, and raised intensity) of vibration exposure. Messenger RNA expression of occludin, zonula occluden-1 (ZO-1), E-cadherin, β-catenin, interleukin 1β (IL-1β), cyclooxygenase-2 (COX-2), transforming growth factor β-1 (TGFβ1), and fibronectin were measured. Tissue structural alterations were assessed using transmission electron microscopy (TEM). Transepithelial resistance was used to measure functional tissue outcomes. Results Occludin gene expression was downregulated in vocal folds exposed to 120 minute time doses of raised intensity phonation, relative to control, and modal intensity phonation. ZO-1 gene expression was upregulated following a 120 minute time dose of modal intensity phonation, compared to control, and downregulated after a 120 minute time dose of raised intensity phonation, compared to modal intensity phonation. E-cadherin gene expression was downregulated after a120 minute time dose of raised intensity phonation, compared to control and modal intensity phonation. TEM revealed extensive desquamation of the stratified squamous epithelial cells with increasing time and magnitude doses of vibration exposure. A general observation of lower transepithelial resistance measures was made in tissues exposed to raised intensity phonation, compared to all other groups. Conclusions This study provides evidence of vocal fold tissue responses to varying time and magnitude doses of vibration exposure. Level of Evidence N/A PMID:25073715

Induction of homologous recombination in Saccharomyces cerevisiae.

PubMed

Simon, J R; Moore, P D

1988-09-01

We have investigated the effects of UV irradiation of Saccharomyces cerevisiae in order to distinguish whether UV-induced recombination results from the induction of enzymes required for homologous recombination, or the production of substrate sites for recombination containing regions of DNA damage. We utilized split-dose experiments to investigate the induction of proteins required for survival, gene conversion, and mutation in a diploid strain of S. cerevisiae. We demonstrate that inducing doses of UV irradiation followed by a 6 h period of incubation render the cells resistant to challenge doses of UV irradiation. The effects of inducing and challenge doses of UV irradiation upon interchromosomal gene conversion and mutation are strictly additive. Using the yeast URA3 gene cloned in non-replicating single- and double-stranded plasmid vectors that integrate into chromosomal genes upon transformation, we show that UV irradiation of haploid yeast cells and homologous plasmid DNA sequences each stimulate homologous recombination approximately two-fold, and that these effects are additive. Non-specific DNA damage has little effect on the stimulation of homologous recombination, as shown by studies in which UV-irradiated heterologous DNA was included in transformation/recombination experiments. We further demonstrate that the effect of competing single- and double-stranded heterologous DNA sequences differs in UV-irradiated and unirradiated cells, suggesting an induction of recombinational machinery in UV-irradiated S. cerevisiae cells.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated networkmore » (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.« less

A Single Dose of LSD Does Not Alter Gene Expression of the Serotonin 2A Receptor Gene (HTR2A) or Early Growth Response Genes (EGR1-3) in Healthy Subjects

PubMed Central

Dolder, Patrick C.; Grünblatt, Edna; Müller, Felix; Borgwardt, Stefan J.; Liechti, Matthias E.

2017-01-01

Rationale: Renewed interest has been seen in the use of lysergic acid diethylamide (LSD) in psychiatric research and practice. The repeated use of LSD leads to tolerance that is believed to result from serotonin (5-HT) 5-HT2A receptor downregulation. In rats, daily LSD administration for 4 days decreased frontal cortex 5-HT2A receptor binding. Additionally, a single dose of LSD acutely increased expression of the early growth response genes EGR1 and EGR2 in rat and mouse brains through 5-HT2A receptor stimulation. No human data on the effects of LSD on gene expression has been reported. Therefore, we investigated the effects of single-dose LSD administration on the expression of the 5-HT2A receptor gene (HTR2A) and EGR1-3 genes. Methods: mRNA expression levels were analyzed in whole blood as a peripheral biomarker in 15 healthy subjects before and 1.5 and 24 h after the administration of LSD (100 μg) and placebo in a randomized, double-blind, placebo-controlled, cross-over study. Results: LSD did not alter the expression of the HTR2A or EGR1-3 genes 1.5 and 24 h after administration compared with placebo. Conclusion: No changes were observed in the gene expression of LSD’s primary target receptor gene or genes that are implicated in its downstream effects. Remaining unclear is whether chronic LSD administration alters gene expression in humans. PMID:28701958

Chronic low-dose γ-irradiation of Drosophila melanogaster larvae induces gene expression changes and enhances locomotive behavior

PubMed Central

Kim, Cha Soon; Seong, Ki Moon; Lee, Byung Sub; Lee, In Kyung; Yang, Kwang Hee; Kim, Ji-Young; Nam, Seon Young

2015-01-01

Although radiation effects have been extensively studied, the biological effects of low-dose radiation (LDR) are controversial. This study investigates LDR-induced alterations in locomotive behavior and gene expression profiles of Drosophila melanogaster. We measured locomotive behavior using larval pupation height and the rapid iterative negative geotaxis (RING) assay after exposure to 0.1 Gy γ-radiation (dose rate of 16.7 mGy/h). We also observed chronic LDR effects on development (pupation and eclosion rates) and longevity (life span). To identify chronic LDR effects on gene expression, we performed whole-genome expression analysis using gene-expression microarrays, and confirmed the results using quantitative real-time PCR. The pupation height of the LDR-treated group at the first larval instar was significantly higher (∼2-fold increase in PHI value, P < 0.05). The locomotive behavior of LDR-treated male flies (∼3 − 5 weeks of age) was significantly increased by 7.7%, 29% and 138%, respectively (P < 0.01), but pupation and eclosion rates and life spans were not significantly altered. Genome-wide expression analysis identified 344 genes that were differentially expressed in irradiated larvae compared with in control larvae. We identified several genes belonging to larval behavior functional groups such as locomotion (1.1%), oxidation reduction (8.0%), and genes involved in conventional functional groups modulated by irradiation such as defense response (4.9%), and sensory and perception (2.5%). Four candidate genes were confirmed as differentially expressed genes in irradiated larvae using qRT-PCR (>2-fold change). These data suggest that LDR stimulates locomotion-related genes, and these genes can be used as potential markers for LDR. PMID:25792464

Low-dose radiation induces Drosophila innate immunity through Toll pathway activation.

PubMed

Seong, Ki Moon; Kim, Cha Soon; Lee, Byung-Sub; Nam, Seon Young; Yang, Kwang Hee; Kim, Ji-Young; Park, Joong-Jean; Min, Kyung-Jin; Jin, Young-Woo

2012-01-01

Numerous studies report that exposing certain organisms to low-dose radiation induces beneficial effects on lifespan, tumorigenesis, and immunity. By analyzing survival after bacterial infection and antimicrobial peptide gene expression in irradiated flies, we demonstrate that low-dose irradiation of Drosophila enhances innate immunity. Low-dose irradiation of flies significantly increased resistance against gram-positive and gram-negative bacterial infections, as well as expression of several antimicrobial peptide genes. Additionally, low-dose irradiation also resulted in a specific increase in expression of key proteins of the Toll signaling pathway and phosphorylated forms of p38 and JNK. These results indicate that innate immunity is activated after low-dose irradiation through Toll signaling pathway in Drosophila.

Radiation dose effect of DNA repair-related gene expression in mouse white blood cells.

PubMed

Li, Ming-juan; Wang, Wei-wei; Chen, Shi-wei; Shen, Qian; Min, Rui

2011-10-01

The aim of this study was to screen molecular biomarkers for biodosimetry from DNA repair-related gene expression profiles. Mice were subjected to whole-body exposure with 60Co gamma rays with a dose range of 0-8 Gy at a dose rate of 0.80 Gy/min. RNA was extracted from the peripheral blood of irradiated mice at 4, 8, 12, 24 and 48hrs post-irradiation. The mRNA transcriptional changes of 11 genes related to DNA damage and repair were detected using real-time quantitative polymerase chain reaction (RT-PCR). Of the 11 genes examined, CDKN1A (cyclin-dependent kinase inhibitor 1A or p21, Cip1) and ATM (ataxia telangiectasia mutated) expression levels were found to be heavily up- and down-regulated, respectively, with exposure dose increasing at different post-irradiation times. RAD50 (RAD50 homolog), PLK3 (polo-like kinase 3), GADD45A (growth arrest and DNA damage-inducible, alpha), DDB2 (damage-specific DNA-binding protein 2), BBC3 (BCL2-binding component 3) and IER5 (immediate early response 5) gene expression levels were found to undergo significant oscillating changes over a broad dose range of 2-8 Gy at post-exposure time points observed. Three of the genes were found not to change within the observed exposure dose and post-radiation time ranges. The results of this study add to the biodosimetry with biomarker data pool and will be helpful for constructing appropriate gene expression biomarker systems to evaluate radiation exposure doses.

Impact of Neutron Exposure on Global Gene Expression in a Human Peripheral Blood Model

PubMed Central

Broustas, Constantinos G.; Xu, Yanping; Harken, Andrew D.; Chowdhury, Mashkura; Garty, Guy; Amundson, Sally A.

2017-01-01

The detonation of an improvised nuclear device would produce prompt radiation consisting of both photons (gamma rays) and neutrons. While much effort in recent years has gone into the development of radiation biodosimetry methods suitable for mass triage, the possible effect of neutrons on the endpoints studied has remained largely uninvestigated. We have used a novel neutron irradiator with an energy spectrum based on that 1–1.5 km from the epicenter of the Hiroshima blast to begin examining the effect of neutrons on global gene expression, and the impact this may have on the development of gene expression signatures for radiation biodosimetry. We have exposed peripheral blood from healthy human donors to 0.1, 0.3, 0.5 or 1 Gy of neutrons ex vivo using our neutron irradiator, and compared the transcriptomic response 24 h later to that resulting from sham exposure or exposure to 0.1, 0.3, 0.5, 1, 2 or 4 Gy of photons (X rays). We identified 125 genes that responded significantly to both radiation qualities as a function of dose, with the magnitude of response to neutrons generally being greater than that seen after X-ray exposure. Gene ontology analysis suggested broad involvement of the p53 signaling pathway and general DNA damage response functions across all doses of both radiation qualities. Regulation of immune response and chromatin-related functions were implicated only following the highest doses of neutrons, suggesting a physiological impact of greater DNA damage. We also identified several genes that seem to respond primarily as a function of dose, with less effect of radiation quality. We confirmed this pattern of response by quantitative real-time RT-PCR for BAX, TNFRSF10B, ITLN2 and AEN and suggest that gene expression may provide a means to differentiate between total dose and a neutron component. PMID:28140791

Impact of Neutron Exposure on Global Gene Expression in a Human Peripheral Blood Model.

PubMed

Broustas, Constantinos G; Xu, Yanping; Harken, Andrew D; Chowdhury, Mashkura; Garty, Guy; Amundson, Sally A

2017-04-01

The detonation of an improvised nuclear device would produce prompt radiation consisting of both photons (gamma rays) and neutrons. While much effort in recent years has gone into the development of radiation biodosimetry methods suitable for mass triage, the possible effect of neutrons on the endpoints studied has remained largely uninvestigated. We have used a novel neutron irradiator with an energy spectrum based on that 1-1.5 km from the epicenter of the Hiroshima blast to begin examining the effect of neutrons on global gene expression, and the impact this may have on the development of gene expression signatures for radiation biodosimetry. We have exposed peripheral blood from healthy human donors to 0.1, 0.3, 0.5 or 1 Gy of neutrons ex vivo using our neutron irradiator, and compared the transcriptomic response 24 h later to that resulting from sham exposure or exposure to 0.1, 0.3, 0.5, 1, 2 or 4 Gy of photons (X rays). We identified 125 genes that responded significantly to both radiation qualities as a function of dose, with the magnitude of response to neutrons generally being greater than that seen after X-ray exposure. Gene ontology analysis suggested broad involvement of the p53 signaling pathway and general DNA damage response functions across all doses of both radiation qualities. Regulation of immune response and chromatin-related functions were implicated only following the highest doses of neutrons, suggesting a physiological impact of greater DNA damage. We also identified several genes that seem to respond primarily as a function of dose, with less effect of radiation quality. We confirmed this pattern of response by quantitative real-time RT-PCR for BAX, TNFRSF10B, ITLN2 and AEN and suggest that gene expression may provide a means to differentiate between total dose and a neutron component.

Effects of γ-radiation on cell growth, cell cycle and promoter methylation of 22 cell cycle genes in the 1321NI astrocytoma cell line.

PubMed

Alghamian, Yaman; Abou Alchamat, Ghalia; Murad, Hossam; Madania, Ammar

2017-09-01

DNA damage caused by radiation initiates biological responses affecting cell fate. DNA methylation regulates gene expression and modulates DNA damage pathways. Alterations in the methylation profiles of cell cycle regulating genes may control cell response to radiation. In this study we investigated the effect of ionizing radiation on the methylation levels of 22 cell cycle regulating genes in correlation with gene expression in 1321NI astrocytoma cell line. 1321NI cells were irradiated with 2, 5 or 10Gy doses then analyzed after 24, 48 and 72h for cell viability using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliu bromide) assay. Flow cytometry were used to study the effect of 10Gy irradiation on cell cycle. EpiTect Methyl II PCR Array was used to identify differentially methylated genes in irradiated cells. Changes in gene expression was determined by qPCR. Azacytidine treatment was used to determine whether DNA methylation affectes gene expression. Our results showed that irradiation decreased cell viability and caused cell cycle arrest at G2/M. Out of 22 genes tested, only CCNF and RAD9A showed some increase in DNA methylation (3.59% and 3.62%, respectively) after 10Gy irradiation, and this increase coincided with downregulation of both genes (by 4 and 2 fold, respectively). with azacytidine confirmed that expression of CCNF and RAD9A genes was regulated by methylation. 1321NI cell line is highly radioresistant and that irradiation of these cells with a 10Gy dose increases DNA methylation of CCNF and RAD9A genes. This dose down-regulates these genes, favoring G2/M arrest. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

Comparison of acute proton, photon, and low-dose priming effects on genes associated with extracellular matrix and adhesion molecules in the lungs

PubMed Central

2013-01-01

Background Crew members on space missions inevitably are exposed to low background radiation and can receive much higher doses during solar particle events (SPE) that consist primarily of protons. Ionizing radiation could cause lung pathologies. Cell adhesion molecules (CAM) are believed to participate in fibrogenesis. Interactions between CAM and extracellular matrix (ECM) affect epithelial repair mechanisms in the lung. However, there are very limited data on biological effects of protons on normal lung tissue. Numerous reports have shown that exposure to low-dose/low-dose-rate (LDR) radiation can result in radioadaptation that renders cells more resistant to subsequent acute radiation. The goal of this study was to compare expression of genes associated with ECM and CAM, as well as critical profibrotic mediators, in mouse lungs after acute irradiation with photons and protons, and also determine whether pre-exposure to LDR γ-rays induces an adaptive effect. Results Overall, a marked difference was present in the proton vs. photon groups in gene expression. When compared to 0 Gy, more genes were affected by protons than by photons at both time points (11 vs. 6 on day 21 and 14 vs. 8 on day 56), and all genes affected by protons were upregulated. Many genes were modulated by LDR γ-rays when combined with photons or protons. Col1a1, mmp14, and mmp15 were significantly upregulated by all radiation regimens on day 21. Similarly, the change in expression of profibrotic proteins was also detected after acute and combination irradiation. Conclusion These data show that marked differences were present between acutely delivered protons and photons in modulating genes, and the effect of protons was more profound than that of photons. Pre-exposure to LDR γ-rays ‘normalized’ some genes that were modified by acute irradiation. PMID:23374750

Tissue-Specific Effects of Reduced β-catenin Expression on Adenomatous Polyposis Coli Mutation-Instigated Tumorigenesis in Mouse Colon and Ovarian Epithelium

PubMed Central

Feng, Ying; Sakamoto, Naoya; Wu, Rong; Liu, Jie-yu; Wiese, Alexandra; Green, Maranne E.; Green, Megan; Akyol, Aytekin; Roy, Badal C.; Zhai, Yali; Cho, Kathleen R.; Fearon, Eric R.

2015-01-01

Adenomatous polyposis coli (APC) inactivating mutations are present in most human colorectal cancers and some other cancers. The APC protein regulates the β-catenin protein pool that functions as a co-activator of T cell factor (TCF)-regulated transcription in Wnt pathway signaling. We studied effects of reduced dosage of the Ctnnb1 gene encoding β-catenin in Apc-mutation-induced colon and ovarian mouse tumorigenesis and cell culture models. Concurrent somatic inactivation of one Ctnnb1 allele, dramatically inhibited Apc mutation-induced colon polyposis and greatly extended Apc-mutant mouse survival. Ctnnb1 hemizygous dose markedly inhibited increases in β-catenin levels in the cytoplasm and nucleus following Apc inactivation in colon epithelium, with attenuated expression of key β-catenin/TCF-regulated target genes, including those encoding the EphB2/B3 receptors, the stem cell marker Lgr5, and Myc, leading to maintenance of crypt compartmentalization and restriction of stem and proliferating cells to the crypt base. A critical threshold for β-catenin levels in TCF-regulated transcription was uncovered for Apc mutation-induced effects in colon epithelium, along with evidence of a feed-forward role for β-catenin in Ctnnb1 gene expression and CTNNB1 transcription. The active β-catenin protein pool was highly sensitive to CTNNB1 transcript levels in colon cancer cells. In mouse ovarian endometrioid adenocarcinomas (OEAs) arising from Apc- and Pten-inactivation, while Ctnnb1 hemizygous dose affected β-catenin levels and some β-catenin/TCF target genes, Myc induction was retained and OEAs arose in a fashion akin to that seen with intact Ctnnb1 gene dose. Our findings indicate Ctnnb1 gene dose exerts tissue-specific differences in Apc mutation-instigated tumorigenesis. Differential expression of selected β-catenin/TCF-regulated genes, such as Myc, likely underlies context-dependent effects of Ctnnb1 gene dosage in tumorigenesis. PMID:26528816

Involvement of Resveratrol and ω-3 Polyunsaturated Fatty Acids on Sirtuin 1 Gene Expression in THP1 Cells.

PubMed

Tsuchiya, Takafumi; Endo, Ayano; Tsujikado, Kyoko; Inukai, Toshihiko

2017-10-01

Resveratrol, a kind of polyphenol, has the potential to activate the longevity gene in several cells, in the same manner as calorie restriction. We investigated the effect of resveratrol and ω-3-line polyunsaturated fatty acid on surtuin 1 (SIRT1) gene expression in human monocytes (THP1) cells. We examined the gene expression of THP1 cells using real-time polymerase chain reaction and Western blotting analysis. Resveratol, eicosapentaenoic acid (EPA) and docosahexaeanoic acid (DHA) as n-3 polyunsaturated fatty acid were added on THP1 cells. We observed the changes in the SIRT1 gene expression in those cells, under various doses of agents and in time courses. Then, we examined the interaction of glucose and mannitol on those agents׳ effect of the gene expression. The concentration range of glucose and mannitol was from 5-20mM, respectively. The SIRT1 gene expression could be defined in 24 and 48 hours both in real-time polymerase chain reaction analysis and in Western blotting. Resveratrol showed SIRT1 gene expression in a dose-dependent manner in the range of 0-20μM in both analyses. Although EPA at 10μM showed marked increase in SIRT1 gene expression compared to control condition in Western blotting, this phenomenon was not in dose-dependent manner. DHA did not exhibit any augmentation of SIRT1 gene expression in a dose-dependent manner in the range of 0-20μM in both analyses. We refined the dose-dependent inhibition of the SIRT1 gene expression within 20mM glucose medium. Although 20mM did not exhibit any inhibition, 10μM resveratrol induced the gene expression compared to control medium. Both 5 and 15mM mannitol medium did not significantly alter basic gene expression and 10μM resveratrol-induced gene expression. The present results suggest that resveratrol and EPA, but not DHA, markedly activated the SIRT1 gene expression in THP1 cells, and that high glucose medium could inhibit the basic gene expression, but not powerful resveratrol-induced gene expression, in those cells. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

Effects of oral exposure to bisphenol A on gene expression and global genomic DNA methylation in the prostate, female mammary gland, and uterus of NCTR Sprague-Dawley rats

PubMed Central

Camacho, Luísa; Basavarajappa, Mallikarjuna S.; Chang, Ching-Wei; Han, Tao; Kobets, Tetyana; Koturbash, Igor; Surratt, Gordon; Lewis, Sherry M.; Vanlandingham, Michelle M.; Fuscoe, James C.; da Costa, Gonçalo Gamboa; Pogribny, Igor P.; Delclos, K. Barry

2015-01-01

Bisphenol A (BPA), an industrial chemical used in the manufacture of polycarbonate and epoxy resins, binds to the nuclear estrogen receptor with an affinity 4–5 orders of magnitude lower than that of estradiol. We reported previously that “high BPA” (100,000 and 300,000 μg/kg body weight (bw)/day), but not “low BPA” [2.5–2700 μg/kg bw/day], induced clear adverse effects in NCTR Sprague-Dawley rats gavaged daily from gestation day 6 through postnatal day 90. The “high BPA” effects partially overlapped those of ethinyl estradiol (EE2, 0.5 and 5.0 μg/kg bw/day). To evaluate further the potential of “low BPA” to induce biological effects, here we assessed the global genomic DNA methylation and gene expression in the prostate and female mammary glands, tissues identified previously as potential targets of BPA, and uterus, a sensitive estrogen-responsive tissue. Both doses of EE2 modulated gene expression, including of known estrogen-responsive genes, and PND 4 global gene expression data showed a partial overlap of the “high BPA” effects with those of EE2. The “low BPA” doses modulated the expression of several genes; however, the absence of a dose response reduces the likelihood that these changes were causally linked to the treatment. These results are consistent with the toxicity outcomes. PMID:25862956

Nonylphenol induces liver toxicity and oxidative stress in rat.

PubMed

Kazemi, Sohrab; Mousavi Kani, Seydeh Narges; Ghasemi-Kasman, Maryam; Aghapour, Fahimeh; Khorasani, Hamidreza; Moghadamnia, Ali Akbar

2016-10-07

Nonylphenol (NP) is one of the most widely used synthetic xenoestrogens in detergents, plastic products, paints and the most important environmental degradation factor. In this study, the effects NP was investigated on hepatic oxidative stress-related gene expression in rats. Wistar male rats weighing 150-200 g were divided into control and NP receiving groups. NP was given in three doses (5, 25, and 125 μg/kg). All doses were given by gavage and the experiment continued for a consecutive 35 days. AST, ALT and ALP determined by the colorimetric method. The RNA was extracted from the rats liver tissue and RT- PCR was used to investigate the changes in gene expression. For this purpose, primers and specific probes of HO1 and Gadd45b genes as well as B-actin as control were prepared and the expression of each gene was separately assessed with ABI-7300. Hematoxylin and eosin staining was performed for evaluating of cell death. The data from our study indicated nonylphenol increased alkaline phosphatase level but not changed aspartate aminotransferase and alanine aminotransferase in serum. That various doses of NP result in a dose-dependent increase in the expression of HO-1 gene. The intensified expression of HO-1 was statistically significant just at the doses of 25 and 125 μg/kg compared to control group (p < 0.05). In addition, it was shown that different doses of nonylphenol raised the expression of Gadd45b gene and this increase was significantly evident at 5 μg/kg (p < 0.05). Histological evaluation also indicated that NP increased hepatocytes cell death. We conclude that NP increased serum alkaline phosphatase, lead to liver damage and can increase the expression of HO1 and Gadd45b genes and may modify the toxic effects on liver through induction of oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Genome-wide gene expression effects in B6C3F1 mouse intestinal epithelia following 7 and 90days of exposure to hexavalent chromium in drinking water.

PubMed

Kopec, Anna K; Kim, Suntae; Forgacs, Agnes L; Zacharewski, Timothy R; Proctor, Deborah M; Harris, Mark A; Haws, Laurie C; Thompson, Chad M

2012-02-15

Chronic administration of high doses of hexavalent chromium [Cr(VI)] as sodium dichromate dihydrate (SDD) elicits alimentary cancers in mice. To further elucidate key events underlying tumor formation, a 90-day drinking water study was conducted in B6C3F1 mice. Differential gene expression was examined in duodenal and jejunal epithelial samples following 7 or 90days of exposure to 0, 0.3, 4, 14, 60, 170 or 520mg/L SDD in drinking water. Genome-wide microarray analyses identified 6562 duodenal and 4448 jejunal unique differentially expressed genes at day 8, and 4630 and 4845 unique changes, respectively, in the duodenum and jejunum at day 91. Comparative analysis identified significant overlap in duodenal and jejunal differential gene expression. Automated dose-response modeling identified >80% of the differentially expressed genes exhibited sigmoidal dose-response curves with EC(50) values ranging from 10 to 100mg/L SDD. Only 16 genes satisfying the dose-dependent differential expression criteria had EC(50) values <10mg/L SDD, 3 of which were regulated by Nrf2, suggesting oxidative stress in response to SDD at low concentrations. Analyses of differentially expressed genes identified over-represented functions associated with oxidative stress, cell cycle, lipid metabolism, and immune responses consistent with the reported effects on redox status and histopathology at corresponding SDD drinking water concentrations. Collectively, these data are consistent with a mode of action involving oxidative stress and cytotoxicity as early key events. This suggests that the tumorigenic effects of chronic Cr(VI) oral exposure likely require chronic tissue damage and compensatory epithelial cell proliferation. Copyright © 2011 Elsevier Inc. All rights reserved.

Expression of genes involved in mouse lung cell differentiation/regulation after acute exposure to photons and protons with or without low-dose preirradiation.

PubMed

Tian, Jian; Zhao, WeiLing; Tian, Sisi; Slater, James M; Deng, Zhiyong; Gridley, Daila S

2011-11-01

The goal of this study was to compare the effects of acute 2 Gy irradiation with photons (0.8 Gy/min) or protons (0.9 Gy/min), both with and without pre-exposure to low-dose/low-dose-rate γ rays (0.01 Gy at 0.03 cGy/h), on 84 genes involved in stem cell differentiation or regulation in mouse lungs on days 21 and 56. Genes with a ≥1.5-fold difference in expression and P < 0.05 compared to 0 Gy controls are emphasized. Two proteins specific for lung stem cells/progenitors responsible for local tissue repair were also compared. Overall, striking differences were present between protons and photons in modulating the genes. More genes were affected by protons than by photons (22 compared to 2 and 6 compared to 2 on day 21 and day 56, respectively) compared to 0 Gy. Preirradiation with low-dose-rate γ rays enhanced the acute photon-induced gene modulation on day 21 (11 compared to 2), and all 11 genes were significantly downregulated on day 56. On day 21, seven genes (aldh2, bmp2, cdc2a, col1a1, dll1, foxa2 and notch1) were upregulated in response to most of the radiation regimens. Immunoreactivity of Clara cell secretory protein was enhanced by all radiation regimens. The number of alveolar type 2 cells positive for prosurfactant protein C in irradiated groups was higher on day 56 (12.4-14.6 cells/100) than on day 21 (8.5-11.2 cells/100) (P < 0.05). Taken together, these results showed that acute photons and protons induced different gene expression profiles in the lungs and that pre-exposure to low-dose-rate γ rays sometimes had modulatory effects. In addition, proteins associated with lung-specific stem cells/progenitors were highly sensitive to radiation.

Insecticide imidacloprid influences cognitive functions and alters learning performance and related gene expression in a rat model.

PubMed

Kara, Murat; Yumrutas, Onder; Demir, Caner F; Ozdemir, Hasan Huseyin; Bozgeyik, Ibrahim; Coskun, Salih; Eraslan, Ersen; Bal, Ramazan

2015-10-01

The potential toxic effects of several pesticides, including imidacloprid on non-target organisms have not been clearly established. Also, the chronic effects of non-toxic doses on cognitive function in mammals are unknown. In this study, the effects of different doses of imidacloprid on learning and memory of infant and adult rats were evaluated, and the expressions of genes synthesizing proteins known to be associated with learning in brain tissues were also documented. 0.5, 2 and 8 mg/kg doses of imidacloprid were administered to newborn infant and adult Wistar albino rats by gavage. Their learning activities were evaluated, and the expression levels of the inotropic glutamate receptor GRIN1, synoptophysin, growth-associated protein 43 and the muscarinic receptor M1 in hippocampus were determined by real-time PCR method. Learning activities were diminished significantly at 2 and 8 mg/kg doses in the infant model groups and at 8 mg/kg dose in adult rats. Also, expression levels of GRIN1, SYP and GAP-43 were found to be insignificantly altered. Only the expression of M1 were significantly changed in high doses of adult group. Thus imidacloprid in high doses causes deterioration in cognitive functions particularly in infant rats, and this deterioration may be associated with changes in the expressions of related genes. © 2015 The Authors. International Journal of Experimental Pathology © 2015 International Journal of Experimental Pathology.

HFE gene mutation is a risk factor for tissue iron accumulation in hemodialysis patients.

PubMed

Turkmen, Ercan; Yildirim, Tolga; Yilmaz, Rahmi; Hazirolan, Tuncay; Eldem, Gonca; Yilmaz, Engin; Aybal Kutlugun, Aysun; Altindal, Mahmut; Altun, Bulent

2017-07-01

HFE gene mutations are responsible from iron overload in general population. Studies in hemodialysis patients investigated the effect of presence of HFE gene mutations on serum ferritin and transferrin saturation (TSAT) with conflicting results. However effect of HFE mutations on iron overload in hemodialysis patients was not previously extensively studied. 36 hemodialysis patients (age 51.3 ± 15.6, (18/18) male/female) and 44 healthy control subjects included in this cross sectional study. Hemoglobin, ferritin, TSAT in the preceding 2 years were recorded. Iron and erythropoietin (EPO) administered during this period were calculated. Iron accumulation in heart and liver was detected by MRI. Relationship between HFE gene mutation, hemoglobin, iron parameters and EPO doses, and tissue iron accumulation were determined. Iron overload was detected in nine (25%) patients. Hemoglobin, iron parameters, weekly EPO doses, and monthly iron doses of patients with and without iron overload were similar. There was no difference between control group and hemodialysis patients with respect to the prevalence of HFE gene mutations. Iron overload was detected in five of eight patients who had HFE gene mutations, but iron overload was present in 4 of 28 patients who had no mutations (P = 0.01). Hemoglobin, iron parameters, erythropoietin, and iron doses were similar in patients with and without gene mutations. HFE gene mutations remained the main determinant of iron overload after multivariate logistic regression analysis (P = 0.02; OR, 11.6). Serum iron parameters were not adequate to detect iron overload and HFE gene mutation was found to be an important risk factor for iron accumulation. © 2017 International Society for Hemodialysis.

Pulmonary instillation of low doses of titanium dioxide nanoparticles in mice leads to particle retention and gene expression changes in the absence of inflammation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Husain, Mainul, E-mail: mainul.husain@hc-sc.gc.ca; Saber, Anne T., E-mail: ats@nrcwe.dk; Guo, Charles, E-mail: charles.guo@hc-sc.gc.ca

2013-06-15

We investigated gene expression, protein synthesis, and particle retention in mouse lungs following intratracheal instillation of varying doses of nano-sized titanium dioxide (nano-TiO{sub 2}). Female C57BL/6 mice were exposed to rutile nano-TiO{sub 2} via single intratracheal instillations of 18, 54, and 162 μg/mouse. Mice were sampled 1, 3, and 28 days post-exposure. The deposition of nano-TiO{sub 2} in the lungs was assessed using nanoscale hyperspectral microscopy. Biological responses in the pulmonary system were analyzed using DNA microarrays, pathway-specific real-time RT-PCR (qPCR), gene-specific qPCR arrays, and tissue protein ELISA. Hyperspectral mapping showed dose-dependent retention of nano-TiO{sub 2} in the lungs upmore » to 28 days post-instillation. DNA microarray analysis revealed approximately 3000 genes that were altered across all treatment groups (± 1.3 fold; p < 0.1). Several inflammatory mediators changed in a dose- and time-dependent manner at both the mRNA and protein level. Although no influx of neutrophils was detected at the low dose, changes in the expression of several genes and proteins associated with inflammation were observed. Resolving inflammation at the medium dose, and lack of neutrophil influx in the lung fluid at the low dose, were associated with down-regulation of genes involved in ion homeostasis and muscle regulation. Our gene expression results imply that retention of nano-TiO{sub 2} in the absence of inflammation over time may potentially perturb calcium and ion homeostasis, and affect smooth muscle activities. - Highlights: • Pulmonary effects following exposure to low doses of nano-TiO{sub 2} were examined. • Particle retention in lungs was assessed using nanoscale hyperspectral microscopy. • Particles persisted up to 28 days in lungs in all dose groups. • Inflammation was the pathway affected in the high dose group at all time points. • Ion homeostasis and muscle activity pathways were affected in the low dose group.« less

Study of the Genes and Mechanism Involved in the Radioadaptive Response

NASA Technical Reports Server (NTRS)

Dasgupta, Pushan R.

2009-01-01

The radioadaptive response is a phenomenon where exposure to a prior low dose of radiation reduces the level of damage induced by a subsequent high radiation dose. The molecular mechanism behind this is still not well understood. Learning more about the radioadaptive response is critical for long duration spaceflight since astronauts are exposed to low levels of cosmic radiation. The micronucleus assay was used to measure the level of damage caused by radiation. Although cells which were not washed with phosphate buffered saline (PBS) after a low priming dose of 5cGy did not show adaptation to the challenge dose, washing the cells with PBS and giving the cells fresh media after the low dose did allow radioadaptation to occur. This is consistent with the results of a previous publication by another research group. In the present study, genes involved in DNA damage signaling and the oxidative stress response were studied using RT PCR techniques in order to look at changes in expression level after the low dose with or without washing. Our preliminary results indicate that upregulation of oxidative stress response genes ANGPTL7, NCF2, TTN, and SRXN1 may be involved in the radioadaptive response. The low dose of radiation alone was found to activate the oxidative stress response genes GPR156 and MTL5, whereas, washing the cells alone caused relatively robust upregulation of the oxidative stress response genes DUSP1 and PTGS2. Washing after the priming dose showed some changes in the expression level of several DNA damage signaling genes. In addition, we studied whether washing the cells after the priming dose has an effect on the level of nitric oxide in both the media and cells, since nitric oxide levels are known to increase in the media of the cells after a high dose of radiation only if the cells were already exposed to a low priming dose. Based on this preliminary study, we propose that washing the cells after priming exposure actually eliminates some factor secreted by the cells that inhibits radioadaptation leading to the upregulation of some genes which initiates the response.

Sub-therapeutic doses of fluvastatin and valsartan are more effective than therapeutic doses in providing beneficial cardiovascular pleiotropic effects in rats: A proof of concept study.

PubMed

Janić, Miodrag; Lunder, Mojca; France Štiglic, Alenka; Jerin, Aleš; Skitek, Milan; Černe, Darko; Marc, Janja; Drevenšek, Gorazd; Šabovič, Mišo

2017-12-01

Statins and sartans can, in therapeutic doses, induce pleiotropic cardiovascular effects. Similar has recently been shown also for sub-therapeutic doses. We thus explored and compared the cardiovascular pleiotropic efficacy of sub-therapeutic vs. therapeutic doses. Wistar rats were randomly divided into 7 groups receiving fluvastatin, valsartan and their combination in sub-therapeutic and therapeutic doses, or saline. After 6weeks, the animals were euthanised, their hearts and thoracic aortas isolated, and blood samples taken. Endothelium-dependent relaxation of the thoracic aortae and ischaemic-reperfusion injury of the isolated hearts were assessed along with the related serum parameters and genes expression. Fluvastatin and valsartan alone or in combination were significantly more effective in sub-therapeutic than therapeutic doses. The sub-therapeutic combination greatly increased thoracic aorta endothelium-dependent relaxation and maximally protected the isolated hearts against ischaemia-reperfusion injury and was thus most effective. Beneficial effects were accompanied by increased levels of nitric oxide (NO) and decreased levels of asymmetric dimethylarginine (ADMA) in the serum (again prominently induced by the sub-therapeutic combination). Furthermore, nitric oxide synthase 3 (NOS3) and endothelin receptor type A (EDNRA) genes expression increased, but only in both combination groups and without significant differences between them. In the therapeutic dose groups, fluvastatin and valsartan decreased cholesterol values and systolic blood pressure. Sub-therapeutic doses of fluvastatin and valsartan are more effective in expressing cardiovascular pleiotropic effects than therapeutic doses of fluvastatin and/or valsartan. These results could be of significant clinical relevance. Copyright © 2017 Elsevier Inc. All rights reserved.

Treatment with low-dose atorvastatin, losartan, and their combination increases expression of vasoactive-related genes in rat aortas.

PubMed

Lunder, Mojca; Drevenšek, Gorazd; Černe, Darko; Marc, Janja; Janić, Miodrag; Šabovič, Mišo

2013-03-01

Recently it has been shown that statins and angiotensin receptor blockers (ARBs) at low doses express beneficial pleiotropic vascular effects. We aimed to explore whether these drugs at low doses induce the expression of vasoactive-related genes. Sixty adult Wistar rats were treated with low-dose atorvastatin (2 mg/kg), low-dose losartan (5 mg/kg), their combination or saline daily for 4, 6, or 8 weeks. Expression of the vasoactive-related genes endothelin receptor type A (EDNRA), endothelial nitric oxide synthase 3 (NOS3), inducible nitric oxide synthase 2 (NOS2), and angiotensin II receptor type 1 (AGTRL1a) was measured in isolated thoracic aortas. Expression of EDNRA gradually decreased, the lowest values being obtained after 8 weeks (low-dose atorvastatin, losartan [1.6- and 1-7-fold vs controls, respectively; both P < .05], and the combination [2.3-fold vs control, P < .001]). The highest values of NOS3 were obtained after 6 weeks (low-dose atorvastatin, losartan, and their combination, 3.1-fold, P < .01; 3.4-fold, P < .001; and 3.6-fold, P < .001 vs controls, respectively) and then declined after 8 weeks. The combination was more effective in inducing total NOS3 expression when compared to the separate drugs (1.4-fold; P < .05). Importantly, expression of NOS3 was associated with increased plasma NO levels and positively correlated with thoracic aorta relaxation. No changes in expression of NOS2 and AGTRL1a were observed. We showed that low-dose atorvastatin or losartan and especially their combination increases the expression of NOS3 and decreases the expression of EDNRA. These findings are valuable in explaining the effectiveness of the "low-dose pharmacological approach" for improvement in arterial function.

Low-dose Norfloxacin-treated leptospires induce less IL-1β release in J774A.1 cells following discrepant leptospiral gene expression.

PubMed

Cao, Yongguo; Xie, Xufeng; Zhang, Wenlong; Wu, Dianjun; Tu, Changchun

2018-06-01

Currently, accumulating evidence is challenging subtherapeutic therapy. Low-dose Norfloxacin (Nor) has been reported to suppress the immune response and worsen leptospirosis. In this study, we investigated the influence of low-dose Nor (0.03 μg/ml, 0.06 μg/ml, 0.125 μg/ml) on leptospiral gene expression and analyzed the immunomodulatory effects of low-dose Nor-treated leptospires in J774A.1 cells. To study the expression profiles of low-dose Nor-treated leptospires, we chose LipL71/LipL21 as reference genes determined by the geNorm applet in this experiment. The results showed that low-dose Nor up-regulated the expression of FlaB and inhibited the expression of 16S rRNA, LipL32, LipL41, Loa22, KdpA, and KdpB compared with the untreated leptospires. These results indicated that low-dose Nor could regulate leptospiral gene expression. Using RT-PCR, the gene expression of IL-1β and TNF-α in J774A.1 cells was detected. Nor-treated leptospires induced higher expression levels of both IL-1β and TNF-α. However, when analyzed by ELISA, the release of mature IL-1β was reduced compared with that observed in cells induced with no Nor-treated leptospires, although the TNF-α protein level showed no significant change. Our study indicated that the gene expression of leptospires could be modulated by low-dose Nor, which induced less IL-1β release in J774A.1 cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

Early brain response to low-dose radiation exposure involves molecular networks and pathways associated with cognitive functions, advanced aging and Alzheimer's disease.

PubMed

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J

2009-01-01

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy and environmental nuclear contamination as well as for Earth-orbit and space missions. Analyses of transcriptome profiles of mouse brain tissue after whole-body irradiation showed that low-dose exposures (10 cGy) induced genes not affected by high-dose radiation (2 Gy) and that low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues and pathways that were specific for brain tissue. Low-dose genes clustered into a saturated network (P < 10(-53)) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified nine neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose irradiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down-regulated in normal human aging and Alzheimer's disease.

Gamma rays induce DNA damage and oxidative stress associated with impaired growth and reproduction in the copepod Tigriopus japonicus.

PubMed

Han, Jeonghoon; Won, Eun-Ji; Lee, Bo-Young; Hwang, Un-Ki; Kim, Il-Chan; Yim, Joung Han; Leung, Kenneth Mei Yee; Lee, Yong Sung; Lee, Jae-Seong

2014-07-01

Nuclear radioisotope accidents are potentially ecologically devastating due to their impact on marine organisms. To examine the effects of exposure of a marine organism to radioisotopes, we irradiated the intertidal copepod Tigriopus japonicus with several doses of gamma radiation and analyzed the effects on mortality, fecundity, and molting by assessing antioxidant enzyme activities and gene expression patterns. No mortality was observed at 96h, even in response to exposure to a high dose (800Gy) of radiation, but mortality rate was significantly increased 120h (5 days) after exposure to 600 or 800Gy gamma ray radiation. We observed a dose-dependent reduction in fecundity of ovigerous females; even the group irradiated with 50Gy showed a significant reduction in fecundity, suggesting that gamma rays are likely to have a population level effect. In addition, we observed growth retardation, particularly at the nauplius stage, in individuals after gamma irradiation. In fact, nauplii irradiated with more than 200Gy, though able to molt to copepodite stage 1, did not develop into adults. Upon gamma radiation, T. japonicus showed a dose-dependent increase in reactive oxygen species (ROS) levels, the activities of several antioxidant enzymes, and expression of double-stranded DNA break damage genes (e.g. DNA-PK, Ku70, Ku80). At a low level (sub-lethal dose) of gamma irradiation, we found dose-dependent upregulation of p53, implying cellular damage in T. japonicus in response to sub-lethal doses of gamma irradiation, suggesting that T. japonicus is not susceptible to sub-lethal doses of gamma irradiation. Additionally, antioxidant genes, phase II enzyme (e.g. GSTs), and cellular chaperone genes (e.g. Hsps) that are involved in cellular defense mechanisms also showed the same expression patterns for sublethal doses of gamma irradiation (50-200Gy). These findings indicate that sublethal doses of gamma radiation can induce oxidative stress-mediated DNA damage and increase the expression of antioxidant enzymes and proteins with chaperone-related functions, thereby significantly affecting life history parameters such as fecundity and molting in the copepod T. japonicus. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of chemical mutagens and carcinogens on gene expression profiles in human TK6 cells.

PubMed

Godderis, Lode; Thomas, Reuben; Hubbard, Alan E; Tabish, Ali M; Hoet, Peter; Zhang, Luoping; Smith, Martyn T; Veulemans, Hendrik; McHale, Cliona M

2012-01-01

Characterization of toxicogenomic signatures of carcinogen exposure holds significant promise for mechanistic and predictive toxicology. In vitro transcriptomic studies allow the comparison of the response to chemicals with diverse mode of actions under controlled experimental conditions. We conducted an in vitro study in TK6 cells to characterize gene expression signatures of exposure to 15 genotoxic carcinogens frequently used in European industries. We also examined the dose-responsive changes in gene expression, and perturbation of biochemical pathways in response to these carcinogens. TK6 cells were exposed at 3 dose levels for 24 h with and without S9 human metabolic mix. Since S9 had an impact on gene expression (885 genes), we analyzed the gene expression data from cells cultures incubated with S9 and without S9 independently. The ribosome pathway was affected by all chemical-dose combinations. However in general, no similar gene expression was observed among carcinogens. Further, pathways, i.e. cell cycle, DNA repair mechanisms, RNA degradation, that were common within sets of chemical-dose combination were suggested by clustergram. Linear trends in dose-response of gene expression were observed for Trichloroethylene, Benz[a]anthracene, Epichlorohydrin, Benzene, and Hydroquinone. The significantly altered genes were involved in the regulation of (anti-) apoptosis, maintenance of cell survival, tumor necrosis factor-related pathways and immune response, in agreement with several other studies. Similarly in S9+ cultures, Benz[a]pyrene, Styrene and Trichloroethylene each modified over 1000 genes at high concentrations. Our findings expand our understanding of the transcriptomic response to genotoxic carcinogens, revealing the alteration of diverse sets of genes and pathways involved in cellular homeostasis and cell cycle control.

Pharmacological effects of biotin.

PubMed

Fernandez-Mejia, Cristina

2005-07-01

In the last few decades, more vitamin-mediated effects have been discovered at the level of gene expression. Increasing knowledge on the molecular mechanisms of these vitamins has opened new perspectives that form a connection between nutritional signals and the development of new therapeutic agents. Besides its role as a carboxylase prosthetic group, biotin regulates gene expression and has a wide repertoire of effects on systemic processes. The vitamin regulates genes that are critical in the regulation of intermediary metabolism: Biotin has stimulatory effects on genes whose action favors hypoglycemia (insulin, insulin receptor, pancreatic and hepatic glucokinase); on the contrary, biotin decreases the expression of hepatic phosphoenolpyruvate carboxykinase, a key gluconeogenic enzyme that stimulates glucose production by the liver. The findings that biotin regulates the expression of genes that are critical in the regulation of intermediary metabolism are in agreement with several observations that indicate that biotin supply is involved in glucose and lipid homeostasis. Biotin deficiency has been linked to impaired glucose tolerance and decreased utilization of glucose. On the other hand, the diabetic state appears to be ameliorated by pharmacological doses of biotin. Likewise, pharmacological doses of biotin appear to decrease plasma lipid concentrations and modify lipid metabolism. The effects of biotin on carbohydrate metabolism and the lack of toxic effects of the vitamin at pharmacological doses suggest that biotin could be used in the development of new therapeutics in the treatment of hyperglycemia and hyperlipidemia, an area that we are actively investigating.

Dose- and Ion-Dependent Effects in the Oxidative Stress Response to Space-Like Radiation Exposure in the Skeletal System

PubMed Central

Alwood, Joshua S.; Tran, Luan H.; Schreurs, Ann-Sofie; Shirazi-Fard, Yasaman; Kumar, Akhilesh; Hilton, Diane; Tahimic, Candice G. T.; Globus, Ruth K.

2017-01-01

Space radiation may pose a risk to skeletal health during subsequent aging. Irradiation acutely stimulates bone remodeling in mice, although the long-term influence of space radiation on bone-forming potential (osteoblastogenesis) and possible adaptive mechanisms are not well understood. We hypothesized that ionizing radiation impairs osteoblastogenesis in an ion-type specific manner, with low doses capable of modulating expression of redox-related genes. 16-weeks old, male, C57BL6/J mice were exposed to low linear-energy-transfer (LET) protons (150 MeV/n) or high-LET 56Fe ions (600 MeV/n) using either low (5 or 10 cGy) or high (50 or 200 cGy) doses at NASA’s Space Radiation Lab. Five weeks or one year after irradiation, tissues were harvested and analyzed by microcomputed tomography for cancellous microarchitecture and cortical geometry. Marrow-derived, adherent cells were grown under osteoblastogenic culture conditions. Cell lysates were analyzed by RT-PCR during the proliferative or mineralizing phase of growth, and differentiation was analyzed by imaging mineralized nodules. As expected, a high dose (200 cGy), but not lower doses, of either 56Fe or protons caused a loss of cancellous bone volume/total volume. Marrow cells produced mineralized nodules ex vivo regardless of radiation type or dose; 56Fe (200 cGy) inhibited osteoblastogenesis by more than 90% (5 weeks and 1 year post-IR). After 5 weeks, irradiation (protons or 56Fe) caused few changes in gene expression levels during osteoblastogenesis, although a high dose 56Fe (200 cGy) increased Catalase and Gadd45. The addition of exogenous superoxide dismutase (SOD) protected marrow-derived osteoprogenitors from the damaging effects of exposure to low-LET (137Cs γ) when irradiated in vitro, but had limited protective effects on high-LET 56Fe-exposed cells. In sum, either protons or 56Fe at a relatively high dose (200 cGy) caused persistent bone loss, whereas only high-LET 56Fe increased redox-related gene expression, albeit to a limited extent, and inhibited osteoblastogenesis. Doses below 50 cGy did not elicit widespread responses in any parameter measured. We conclude that high-LET irradiation at 200 cGy impaired osteoblastogenesis and regulated steady-state gene expression of select redox-related genes during osteoblastogenesis, which may contribute to persistent bone loss. PMID:28994728

Gene Expression in Parp1 Deficient Mice Exposed to a Median Lethal Dose of Gamma Rays.

PubMed

Kumar, M A Suresh; Laiakis, Evagelia C; Ghandhi, Shanaz A; Morton, Shad R; Fornace, Albert J; Amundson, Sally A

2018-05-10

There is a current interest in the development of biodosimetric methods for rapidly assessing radiation exposure in the wake of a large-scale radiological event. This work was initially focused on determining the exposure dose to an individual using biological indicators. Gene expression signatures show promise for biodosimetric application, but little is known about how these signatures might translate for the assessment of radiological injury in radiosensitive individuals, who comprise a significant proportion of the general population, and who would likely require treatment after exposure to lower doses. Using Parp1 -/- mice as a model radiation-sensitive genotype, we have investigated the effect of this DNA repair deficiency on the gene expression response to radiation. Although Parp1 is known to play general roles in regulating transcription, the pattern of gene expression changes observed in Parp1 -/- mice 24 h postirradiation to a LD 50/30 was remarkably similar to that in wild-type mice after exposure to LD 50/30 . Similar levels of activation of both the p53 and NFκB radiation response pathways were indicated in both strains. In contrast, exposure of wild-type mice to a sublethal dose that was equal to the Parp1 -/- LD 50/30 , which resulted in a lower magnitude gene expression response. Thus, Parp1 -/- mice displayed a heightened gene expression response to radiation, which was more similar to the wild-type response to an equitoxic dose than to an equal absorbed dose. Gene expression classifiers trained on the wild-type data correctly identified all wild-type samples as unexposed, exposed to a sublethal dose or exposed to an LD 50/30 . All unexposed samples from Parp1 -/- mice were also correctly classified with the same gene set, and 80% of irradiated Parp1 -/- samples were identified as exposed to an LD 50/30 . The results of this study suggest that, at least for some pathways that may influence radiosensitivity in humans, specific gene expression signatures have the potential to accurately detect the extent of radiological injury, rather than serving only as a surrogate of physical radiation dose.

Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

PubMed

Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

2016-02-01

Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

Gene Profiling Characteristics of Radioadaptive Response in AG01522 Normal Human Fibroblasts

PubMed Central

Hou, Jue; Wang, Fan; Kong, Peizhong; Yu, Peter K. N.; Wang, Hongzhi; Han, Wei

2015-01-01

Radioadaptive response (RAR) in mammalian cells refers to the phenomenon where a low-dose ionizing irradiation alters the gene expression profiles, and protects the cells from the detrimental effects of a subsequent high dose exposure. Despite the completion of numerous experimental studies on RAR, the underlying mechanism has remained unclear. In this study, we aimed to have a comprehensive investigation on the RAR induced in the AG01522 human fibroblasts first exposed to 5 cGy (priming dose) and then followed by 2 Gy (challenge dose) of X-ray through comparisons to those cells that had only received a single 2 Gy dose. We studied how the priming dose affected the expression of gene transcripts, and to identify transcripts or pathways that were associated with the reduced chromosomal damages (in terms of the number of micronuclei) after application of the challenging dose. Through the mRNA and microRNA microarray analyses, the transcriptome alteration in AG01522 cells was examined, and the significantly altered genes were identified for different irradiation procedures using bioinformatics approaches. We observed that a low-dose X-ray exposure produced an alert, triggering and altering cellular responses to defend against subsequent high dose-induced damages, and accelerating the cell repair process. Moreover, the p53 signaling pathway was found to play critial roles in regulating DNA damage responses at the early stage after application of the challenging dose, particularly in the RAR group. Furthermore, microRNA analyses also revealed that cell communication and intercellular signaling transduction played important roles after low-dose irradiation. We conclude that RAR benefits from the alarm mechanisms triggered by a low-dose priming radation dose. PMID:25886619

Naltrexone at low doses upregulates a unique gene expression not seen with normal doses: Implications for its use in cancer therapy.

PubMed

Liu, Wai M; Scott, Katherine A; Dennis, Jayne L; Kaminska, Elwira; Levett, Alan J; Dalgleish, Angus G

2016-08-01

It has been reported that lower doses of the opioid antagonist naltrexone are able to reduce tumour growth by interfering with cell signalling as well as by modifying the immune system. We have evaluated the gene expression profile of a cancer cell line after treatment with low-dose naltrexone (LDN), and assessed the effect that adapting treatment schedules with LDN may have on enhancing efficacy. LDN had a selective impact on genes involved with cell cycle regulation and immune modulation. Similarly, the pro-apoptotic genes BAD and BIK1 were increased only after LDN. Continuous treatment with LDN had little effect on growth in different cell lines; however, altering the treatment schedule to include a phase of culture in the absence of drug following an initial round of LDN treatment, resulted in enhanced cell killing. Furthermore, cells pre-treated with LDN were more sensitive to the cytotoxic effects of a number of common chemotherapy agents. For example, priming HCT116 with LDN before treatment with oxaliplatin significantly increased cell killing to 49±7.0 vs. 14±2.4% in cultures where priming was not used. Interestingly, priming with NTX before oxaliplatin resulted in just 32±1.8% cell killing. Our data support further the idea that LDN possesses anticancer activity, which can be improved by modifying the treatment schedule.

A Study of the Differential Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Gene Expression Profiles of Stimulated Thp-1 Macrophages.

PubMed

Allam-Ndoul, Bénédicte; Guénard, Frédéric; Barbier, Olivier; Vohl, Marie-Claude

2017-04-25

Background: An appropriate intake of omega-3 ( n -3) fatty acids (FAs) such as eicosapentaenoic and docosahexaenoic acid (EPA/DHA) from marine sources is known to have anti-inflammatory effects. However, molecular mechanisms underlying their beneficial effects on health are not fully understood. The aim of the present study was to characterize gene expression profiles of THP-1 macrophages, incubated in either EPA or DHA and stimulated with lipopolysaccharide (LPS), a pro-inflammatory agent. Methods: THP-1 macrophages were incubated into 10, 50 and 75 µM of EPA or DHA for 24 h, and 100 nM of LPS was added to the culture media for 18 h. Total mRNA was extracted and gene expression examined by microarray analysis using Illumina Human HT-12 expression beadchips (Illumina). Results: Pathway analysis revealed that EPA and DHA regulate genes involved in cell cycle regulation, apoptosis, immune response and inflammation, oxidative stress and cancer pathways in a differential and dose-dependent manner. Conclusions: EPA and DHA appear to exert differential effects on gene expression in THP-1 macrophages. Specific effects of n -3 FAs on gene expression levels are also dose-dependent.

Molecular and Histopathological Changes in Mouse Intestinal Tissue after Proton Exposure

NASA Astrophysics Data System (ADS)

Purgason, Ashley; Zhang, Ye; Hamilton, Stanley; Wu, Honglu

Radiation in space, especially energetic protons emitted from solar particle events (SPEs), poses serious health risks to astronauts and is especially dangerous for long duration missions. Protons are the most abundant particles in space and to date there is little known about the details of the negative consequences crew members will face upon exposure to them. To elucidate some of the possible health effects induced by protons, BALB/C mice were subjected to 250 MeV of proton radiation at doses of 0 Gy, 0.1 Gy, 1 Gy, and 2 Gy. Three specimens per dose were studied. The gastrointestinal tract of each animal was dissected four hours post-irradiation and the isolated small intestinal tissue was fixed in formalin for histopathological examination or snap-frozen in liquid nitrogen for RNA isolation. Histopathologic observation of the tissue using standard HE staining methods to screen for morphologic changes showed a marked increase in apoptotic lesions for even the lowest dose of 0.1 Gy, and the dose response showed possible hyper sensitivities at low dose. Tissue of the gastrointestinal tract was also homogenized and RNA was isolated for cDNA synthesis and real-time PCR analysis for genes involved in apoptosis. Results of gene expression changes revealed consistent up or down regulation of a number of genes for all of the exposure doses that may play a role in proton-induced apoptosis (e.g. Hsp90ab1). In addition, several genes were found to have significant changes in the RNA level after only the low dose (0.1 Gy), but not the high dose (1 and 2 Gy), proton exposures (e.g. Bok and Casp1), whereas some genes had expression changes only after high dose proton exposures (e.g. Tsc22d3). These findings demonstrated that apoptosis may occur in gastrointestinal tracts after even low dose proton exposures, and the different gene expression patterns between low and high dose proton irradiated mice may offer insight into the molecular mechanisms of the possible hyper sensitivity at low proton doses.

Analysis of cellular response by exposure to acute or chronic radiation in human lymphoblastoid TK-6 cells

NASA Astrophysics Data System (ADS)

Ohnishi, T.; Yasumoto, J.; Takahashi, A.; Ohnishi, K.

To clarify the biological effects of low-dose rate radiation on human health for long-term stay in space, we analyzed the induction of apoptosis and apoptosis-related gene expression after irradiation with different dose-rate in human lymphoblastoid TK-6 cells harboring wild-type p53 gene. We irradiated TK-6 cells by X-ray at 1.5 Gy (1 Gy/min) and then sampled at 25 hr after culturing. We also irradiated by gamma-ray at 1.5 Gy (1 mGy/min) and then sampled immediately or 25 hr after irradiation. For DNA ladder analysis, we extracted DNA from these samples and electrophoresed with 2% agarose gel. In addition, we extracted mRNA from these samples for DNA-array analysis. mRNA from non-irradiated cells was used as a control. After labeling the cDNA against mRNA with [α -33P]-dCTP and hybridizing onto DNA array (Human Apoptosis Expression Array, R&D Systems), we scanned the profiles of the spots by a phosphorimager (BAS5000, FUJI FILM) and calculated using a NIH Image program. The data of each DNA-array were normalized with eight kinds of house keeping genes. We analyzed the expression level of apoptosis-related genes such as p53-related, Bcl-2 family, Caspase family and Fas-related genes. DNA ladders were obviously detected in the cells exposed to a high dose-rate radiation. We detected the induction of the gene expression of apoptosis-promotive genes. In contrast, almost no apoptosis was observed in the cells exposed to the chronic radiation at a low dose-rate. In addition, we detected the induction of the gene expression of apoptosis-suppressive genes as compared with apoptosis promotive-genes immediately after chronic irradiation. These results lead the importance of biological meaning of exposure to radiation at low dose-rate from an aspect of carcinogenesis. Finally, the effects of chronic irradiation become a highly important issue in space radiation biology for human health.

Changes in mammary histology and transcriptome profiles by low-dose exposure to environmental phenols at critical windows of development.

PubMed

Gopalakrishnan, Kalpana; Teitelbaum, Susan L; Lambertini, Luca; Wetmur, James; Manservisi, Fabiana; Falcioni, Laura; Panzacchi, Simona; Belpoggi, Fiorella; Chen, Jia

2017-01-01

Exposure to environmental chemicals has been linked to altered mammary development and cancer risk at high doses using animal models. Effects at low doses comparable to human exposure remain poorly understood, especially during critical developmental windows. We investigated the effects of two environmental phenols commonly used in personal care products - methyl paraben (MPB) and triclosan (TCS) - on the histology and transcriptome of normal mammary glands at low doses mimicking human exposure during critical windows of development. Sprague-Dawley rats were exposed during perinatal, prepubertal and pubertal windows, as well as from birth to lactation. Low-dose exposure to MPB and TCS induced measurable changes in both mammary histology (by Masson's Trichrome Stain) and transcriptome (by microarrays) in a window-specific fashion. Puberty represented a window of heightened sensitivity to MPB, with increased glandular tissue and changes of expression in 295 genes with significant enrichment in functions such as DNA replication and cell cycle regulation. Long-term exposure to TCS from birth to lactation was associated with increased adipose and reduced glandular and secretory tissue, with expression alterations in 993 genes enriched in pathways such as cholesterol synthesis and adipogenesis. Finally, enrichment analyses revealed that genes modified by MPB and TCS were over-represented in human breast cancer gene signatures, suggesting possible links with breast carcinogenesis. These findings highlight the issues of critical windows of susceptibility that may confer heightened sensitivity to environmental insults and implicate the potential health effects of these ubiquitous environmental chemicals in breast cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

Changes in Mammary Histology and Transcriptome Profiles by Low-Dose Exposure to Environmental Phenols at Critical Windows of Development1

PubMed Central

Gopalakrishnan, Kalpana; Teitelbaum, Susan L.; Lambertini, Luca; Wetmur, James; Manservisi, Fabiana; Falcioni, Laura; Panzacchi, Simona; Belpoggi, Fiorella; Chen, Jia

2016-01-01

Exposure to environmental chemicals has been linked to altered mammary development and cancer risk at high doses using animal models. Effects at low doses comparable to human exposure remain poorly understood, especially during critical developmental windows. We investigated the effects of two environmental phenols commonly used in personal care products – methyl paraben (MPB) and triclosan (TCS) – on the histology and transcriptome of normal mammary glands at low doses mimicking human exposure during critical windows of development. Sprague-Dawley rats were exposed during perinatal, prepubertal and pubertal windows, as well as from birth to lactation. Low-dose exposure to MPB and TCS induced measurable changes in both mammary histology (by Masson’s Trichrome Stain) and transcriptome (by microarrays) in a window-specific fashion. Puberty represented a window of heightened sensitivity to MPB, with increased glandular tissue and changes of expression in 295 genes with significant enrichment in functions such as DNA replication and cell cycle regulation. Long-term exposure to TCS from birth to lactation was associated with increased adipose and reduced glandular and secretory tissue, with expression alterations in 993 genes enriched in pathways such as cholesterol synthesis and adipogenesis. Finally, enrichment analyses revealed that genes modified by MPB and TCS were over-represented in human breast cancer gene signatures, suggesting possible links with breast carcinogenesis. These findings highlight the issues of critical windows of susceptibility that may confer heightened sensitivity to environmental insults and implicate the potential health effects of these ubiquitous environmental chemicals in breast cancer. PMID:27810681

Transcriptional response of rat frontal cortex following acute In Vivo exposure to the pyrethroid insecticides permethrin and deltamethrin

PubMed Central

Harrill, Joshua A; Li, Zhen; Wright, Fred A; Radio, Nicholas M; Mundy, William R; Tornero-Velez, Rogelio; Crofton, Kevin M

2008-01-01

Background Pyrethroids are neurotoxic pesticides that interact with membrane bound ion channels in neurons and disrupt nerve function. The purpose of this study was to characterize and explore changes in gene expression that occur in the rat frontal cortex, an area of CNS affected by pyrethroids, following an acute low-dose exposure. Results Rats were acutely exposed to either deltamethrin (0.3 – 3 mg/kg) or permethrin (1 – 100 mg/kg) followed by collection of cortical tissue at 6 hours. The doses used range from those that cause minimal signs of intoxication at the behavioral level to doses well below apparent no effect levels in the whole animal. A statistical framework based on parallel linear (SAM) and isotonic regression (PIR) methods identified 95 and 53 probe sets as dose-responsive. The PIR analysis was most sensitive for detecting transcripts with changes in expression at the NOAEL dose. A sub-set of genes (Camk1g, Ddc, Gpd3, c-fos and Egr1) was then confirmed by qRT-PCR and examined in a time course study. Changes in mRNA levels were typically less than 3-fold in magnitude across all components of the study. The responses observed are consistent with pyrethroids producing increased neuronal excitation in the cortex following a low-dose in vivo exposure. In addition, Significance Analysis of Function and Expression (SAFE) identified significantly enriched gene categories common for both pyrethroids, including some relating to branching morphogenesis. Exposure of primary cortical cell cultures to both compounds resulted in an increase (~25%) in the number of neurite branch points, supporting the results of the SAFE analysis. Conclusion In the present study, pyrethroids induced changes in gene expression in the frontal cortex near the threshold for decreases in ambulatory motor activity in vivo. The penalized regression methods performed similarly in detecting dose-dependent changes in gene transcription. Finally, SAFE analysis of gene expression data identified branching morphogenesis as a biological process sensitive to pyrethroids and subsequent in vitro experiments confirmed this predicted effect. The novel findings regarding pyrethroid effects on branching morphogenesis indicate these compounds may act as developmental neurotoxicants that affect normal neuronal morphology. PMID:19017407

Systemic Administration of a Cyclic Signal Transducer and Activator of Transcription 3 (STAT3) Decoy Oligonucleotide Inhibits Tumor Growth without Inducing Toxicological Effects

PubMed Central

Sen, Malabika; Paul, Kathleen; Freilino, Maria L; Li, Hua; Li, Changyou; Johnson, Daniel E; Wang, Lin; Eiseman, Julie; Grandis, Jennifer R

2014-01-01

Hyperactivation of signal transducer and activator of transcription 3 (STAT3) has been linked to tumorigenesis in most malignancies, including head and neck squamous cell carcinoma. Intravenous delivery of a chemically modified cyclic STAT3 decoy oligonucleotide with improved serum and thermal stability demonstrated antitumor efficacy in conjunction with downmodulation of STAT3 target gene expression such as cyclin D1 and Bcl-XL in a mouse model of head and neck squamous cell carcinoma. The purpose of the present study was to determine the toxicity and dose-dependent antitumor efficacy of the cyclic STAT3 decoy after multiple intravenous doses in Foxn1 nu mice in anticipation of clinical translation. The two doses (5 and 10 mg/kg) of cyclic STAT3 decoy demonstrated a significant decrease in tumor volume compared with the control groups (mutant cyclic STAT3 decoy or saline) in conjunction with downmodulation of STAT3 target gene expression. There was no dose-dependent effect of cyclic STAT3 decoy on tumor volume or STAT3 target gene expression. There were no significant changes in body weights between the groups during the dosing period, after the dosing interval or on the day of euthanasia. No hematology or clinical chemistry parameters suggested toxicity of the cyclic STAT3 decoy compared with saline control. No gross or histological pathological abnormalities were noted at necropsy in any of the animals. These findings suggest a lack of toxicity of intravenous administration of a cyclic STAT3 decoy oligonucleotide. In addition, comparable antitumor effects indicate a lack of dose response at the two dose levels investigated. PMID:24395569

Reward and Toxicity of Cocaine Metabolites Generated by Cocaine Hydrolase.

PubMed

Murthy, Vishakantha; Geng, Liyi; Gao, Yang; Zhang, Bin; Miller, Jordan D; Reyes, Santiago; Brimijoin, Stephen

2015-08-01

Butyrylcholinesterase (BChE) gene therapy is emerging as a promising concept for treatment of cocaine addiction. BChE levels after gene transfer can rise 1000-fold above those in untreated mice, making this enzyme the second most abundant plasma protein. For months or years, gene transfer of a BChE mutated into a cocaine hydrolase (CocH) can maintain enzyme levels that destroy cocaine within seconds after appearance in the blood stream, allowing little to reach the brain. Rapid enzyme action causes a sharp rise in plasma levels of two cocaine metabolites, benzoic acid (BA) and ecgonine methyl ester (EME), a smooth muscle relaxant that is mildly hypotensive and, at best, only weakly rewarding. The present study, utilizing Balb/c mice, tested reward effects and cardiovascular effects of administering EME and BA together at molar levels equivalent to those generated by a given dose of cocaine. Reward was evaluated by conditioned place preference. In this paradigm, cocaine (20 mg/kg) induced a robust positive response but the equivalent combined dose of EME + BA failed to induce either place preference or aversion. Likewise, mice that had undergone gene transfer with mouse CocH (mCocH) showed no place preference or aversion after repeated treatments with a near-lethal 80 mg/kg cocaine dose. Furthermore, a single administration of that same high cocaine dose failed to affect blood pressure as measured using the noninvasive tail-cuff method. These observations confirm that the drug metabolites generated after CocH gene transfer therapy are safe even after a dose of cocaine that would ordinarily be lethal.

Genotoxic chemical carcinogens target inducible genes in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamilton, J.W.; McCaffrey, J.; Caron, R.M.

1994-12-31

Our laboratory is interested in whether carcinogen-induced DNA damage is distributed nonrandomly in the genome - that is, {open_quotes}targeted{close_quotes} to specific genes or gene regions in vivo. As an indirect measure of whether targeting occurs at the gene level, we have examined whether carcinogens differentially alter the expression of individual genes. We have compared the effects of model genotoxic carcinogens that principally induce either strand breaks, simple alkylations, bulky lesions, or DNA cross-links on the expression of several constitutive and inducible genes in a simple in vivo system, the chick embryo. Each agent was examined for its effects on genemore » expression over a 24 hour period corresponding to the period of maximal DNA damage and repair induced by each compound. The doses used in these studies represented the maximum doses that caused no overt toxicity over a 96 hour period but that induced significant levels of DNA damage. Our results demonstrate that inducible genes are targeted by chemical carcinogens. We hypothesize that such effects may be a result of DNA damage specifically altering DNA-protein interactions within the promoters of inducible genes.« less

Low doses of paclitaxel enhance liver metastasis of breast cancer cells in the mouse model.

PubMed

Li, Qi; Ma, Zhuang; Liu, Yinhua; Kan, Xiaoxi; Wang, Changjun; Su, Bingnan; Li, Yuchen; Zhang, Yingmei; Wang, Pingzhang; Luo, Yang; Na, Daxiang; Wang, Lanlan; Zhang, Guoying; Zhu, Xiaoxin; Wang, Lu

2016-08-01

Paclitaxel is the most commonly used chemotherapeutic agent in breast cancer treatment. In addition to its well-known cytotoxic effects, recent studies have shown that paclitaxel has tumor-supportive activities. Importantly, paclitaxel levels are not maintained at the effective concentration through one treatment cycle; rather, the concentration decreases during the cycle as a result of drug metabolism. Therefore, a comprehensive understanding of paclitaxel's effects requires insight into the dose-specific activities of paclitaxel and their influence on cancer cells and the host microenvironment. Here we report that a low dose of paclitaxel enhances metastasis of breast cancer cells to the liver in mouse models. We used microarray analysis to investigate gene expression patterns in invasive breast cancer cells treated with low or clinically relevant high doses of paclitaxel. We also investigated the effects of low doses of paclitaxel on cell migration, invasion and metastasis in vitro and in vivo. The results showed that low doses of paclitaxel promoted inflammation and initiated the epithelial-mesenchymal transition, which enhanced tumor cell migration and invasion in vitro. These effects could be reversed by inhibiting NF-κB. Furthermore, low doses of paclitaxel promoted liver metastasis in mouse xenografts, which correlated with changes in estrogen metabolism in the host liver. Collectively, these findings reveal the paradoxical and dose-dependent effects of paclitaxel on breast cancer cell activity, and suggest that increased consideration be given to potential adverse effects associated with low concentrations of paclitaxel during treatment. Gene expression microarray data are available in the GEO database under accession number GSE82048. © 2016 Federation of European Biochemical Societies.

Imprinted genes and transpositions: epigenomic targets for low dose radiation effects. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jirtle, Randy L.

2012-10-11

The overall hypothesis of this grant application is that low dose ionizing radiation (LDIR) elicits adaptive responses in part by causing heritable DNA methylation changes in the epigenome. This novel postulate was tested by determining if the level of DNA methylation at the Agouti viable yellow (A{sup vy}) metastable locus is altered, in a dose-dependent manner, by low dose radiation exposure (<10 cGy) during early gestation. This information is particularly important to ascertain given the increased use of CT scans in disease diagnosis, increased number of people predicted to live and work in space, and the present concern about radiologicalmore » terrorism. We showed for the first time that LDIR significantly increased DNA methylation at the A{sup vy} locus in a sex-specific manner (p=0.004). Average DNA methylation was significantly increased in male offspring exposed to doses between 0.7 cGy and 7.6 cGy with maximum effects at 1.4 cGy and 3.0 cGy (p<0.01). Offspring coat color was concomitantly shifted towards pseudoagouti (p<0.01). Maternal dietary antioxidant supplementation mitigated both the DNA methylation changes and coat color shift in the irradiated offspring (p<0.05). Thus, LDIR exposure during gestation elicits epigenetic alterations that lead to positive adaptive phenotypic changes that are negated with antioxidants, indicating they are mediated in part by oxidative stress. These findings provide evidence that in the isogenic Avy mouse model epigenetic alterations resulting from LDIR play a role in radiation hormesis, bringing into question the assumption that every dose of radiation is harmful. Our findings not only have significant implications concerning the mechanism of hormesis, but they also emphasize the potential importance of this phenomenon in determining human risk at low radiation doses. Since the epigenetic regulation of genes varies markedly between species, the effect of LDIR on other epigenetically labile genes (e.g. imprinted genes) in animals and humans needs to be defined.« less

Radioadaptive Cytoprotective Pathways in the Mouse Retina

NASA Technical Reports Server (NTRS)

Zanello, Susana B.; Wotring, V.; Theriot, C.; Ploutz-Snyder, R.; Zhang, Y.; Wu, H.

2010-01-01

Exposure to cosmic radiation implies a risk of tissue degeneration. Radiation retinopathy is a complication of radiotherapy and exhibits common features with other retinopathies and neuropathies. Exposure to a low radiation dose elicits protective cellular events (radioadaptive response), reducing the stress of a subsequent higher dose. To assess the risk of radiation-induced retinal changes and the extent to which a small priming dose reduces this risk, we used a mouse model exposed to a source of Cs-137-gamma radiation. Gene expression profiling of retinas from non-irradiated control C57BL/6J mice (C) were compared to retinas from mice treated with a low 50 mGy dose (LD), a high 6 Gy dose (HD), and a combined treatment of 50 mGy (priming) and 6 Gy (challenge) doses (LHD). Whole retina RNA was isolated and expression analysis for selected genes performed by RTqPCR. Relevant target genes associated with cell death/survival, oxidative stress, cellular stress response and inflammation pathways, were analyzed. Cellular stress response genes were upregulated at 4 hr after the challenge dose in LHD retinas (Sirt1: 1.5 fold, Hsf1: 1.7 fold, Hspa1a: 2.5 fold; Hif1a: 1.8 fold, Bag1: 1.7). A similar trend was observed in LD animals. Most antioxidant enzymes (Hmox1, Sod2, Prdx1, Cygb, Cat1) and inflammatory mediators (NF B, Ptgs2 and Tgfb1) were upregulated in LHD and LD retinas. Expression of the pro-survival gene Bcl2 was upregulated in LD (6-fold) and LHD (4-fold) retinas. In conclusion, cytoprotective gene networks activation in the retina suggests a radioadaptive response to a priming irradiation dose, with mitigation of the deleterious effects of a subsequent high dose exposure. The enhancement of these cytoprotective mechanisms has potential value as a countermeasure to ocular alterations caused by radiation alone or in combination with other factors in spaceflight environments.

Intraperitoneal AAV9-shRNA inhibits target expression in neonatal skeletal and cardiac muscles.

PubMed

Mayra, Azat; Tomimitsu, Hiroyuki; Kubodera, Takayuki; Kobayashi, Masaki; Piao, Wenying; Sunaga, Fumiko; Hirai, Yukihiko; Shimada, Takashi; Mizusawa, Hidehiro; Yokota, Takanori

2011-02-11

Systemic injections of AAV vectors generally transduce to the liver more effectively than to cardiac and skeletal muscles. The short hairpin RNA (shRNA)-expressing AAV9 (shRNA-AAV9) can also reduce target gene expression in the liver, but not enough in cardiac or skeletal muscles. Higher doses of shRNA-AAV9 required for inhibiting target genes in cardiac and skeletal muscles often results in shRNA-related toxicity including microRNA oversaturation that can induce fetal liver failure. In this study, we injected high-dose shRNA-AAV9 to neonates and efficiently silenced genes in cardiac and skeletal muscles without inducing liver toxicity. This is because AAV is most likely diluted or degraded in the liver than in cardiac or skeletal muscle during cell division after birth. We report that this systemically injected shRNA-AAV method does not induce any major side effects, such as liver dysfunction, and the dose of shRNA-AAV is sufficient for gene silencing in skeletal and cardiac muscle tissues. This novel method may be useful for generating gene knockdown in skeletal and cardiac mouse tissues, thus providing mouse models useful for analyzing diseases caused by loss-of-function of target genes. Copyright © 2011 Elsevier Inc. All rights reserved.

Arsenic as an endocrine disruptor: arsenic disrupts retinoic acid receptor-and thyroid hormone receptor-mediated gene regulation and thyroid hormone-mediated amphibian tail metamorphosis.

PubMed

Davey, Jennifer C; Nomikos, Athena P; Wungjiranirun, Manida; Sherman, Jenna R; Ingram, Liam; Batki, Cavus; Lariviere, Jean P; Hamilton, Joshua W

2008-02-01

Chronic exposure to excess arsenic in drinking water has been strongly associated with increased risks of multiple cancers, diabetes, heart disease, and reproductive and developmental problems in humans. We previously demonstrated that As, a potent endocrine disruptor at low, environmentally relevant levels, alters steroid signaling at the level of receptor-mediated gene regulation for all five steroid receptors. The goal of this study was to determine whether As can also disrupt gene regulation via the retinoic acid (RA) receptor (RAR) and/or the thyroid hormone (TH) receptor (TR) and whether these effects are similar to previously observed effects on steroid regulation. Human embryonic NT2 or rat pituitary GH3 cells were treated with 0.01-5 microM sodium arsenite for 24 hr, with or without RA or TH, respectively, to examine effects of As on receptor-mediated gene transcription. At low, noncytotoxic doses, As significantly altered RAR-dependent gene transcription of a transfected RAR response element-luciferase construct and the native RA-inducible cytochrome P450 CYP26A gene in NT2 cells. Likewise, low-dose As significantly altered expression of a transfected TR response element-luciferase construct and the endogenous TR-regulated type I deiodinase (DIO1) gene in a similar manner in GH3 cells. An amphibian ex vivo tail metamorphosis assay was used to examine whether endocrine disruption by low-dose As could have specific pathophysiologic consequences, because tail metamorphosis is tightly controlled by TH through TR. TH-dependent tail shrinkage was inhibited in a dose-dependent manner by 0.1- 4.0 microM As. As had similar effects on RAR- and TR-mediated gene regulation as those previously observed for the steroid receptors, suggesting a common mechanism or action. Arsenic also profoundly affected a TR-dependent developmental process in a model animal system at very low concentrations. Because RAR and TH are critical for both normal human development and adult function and their dysregulation is associated with many disease processes, disruption of these hormone receptor-dependent processes by As is also potentially relevant to human developmental problems and disease risk.

Dose-dependent Effect of Boric Acid on Myogenic Differentiation of Human Adipose-derived Stem Cells (hADSCs).

PubMed

Apdik, Hüseyin; Doğan, Ayşegül; Demirci, Selami; Aydın, Safa; Şahin, Fikrettin

2015-06-01

Boron, a vital micronutrient for plant metabolism, is not fully elucidated for embryonic and adult body development, and tissue regeneration. Although optimized amount of boron supplement has been shown to be essential for normal gestational development in zebrafish and frog and beneficial for bone regeneration in higher animals, effects of boron on myogenesis and myo-regeneration remains to be solved. In the current study, we investigated dose-dependent activity of boric acid on myogenic differentiation of human adipose-derived stem cells (hADSCs) using immunocytochemical, gene, and protein expression analysis. The results revealed that while low- (81.9 μM) and high-dose (819.6 μM) boron treatment increased myogenic gene expression levels such as myosin heavy chain (MYH), MyoD, myogenin, and desmin at day 4 of differentiation, high-dose treatment decreased myogenic-related gene and protein levels at day 21 of differentiation, confirmed by immunocytochemical analysis. The findings of the study present not only an understanding of boron's effect on myogenic differentiation but also an opportunity for the development of scaffolds to be used in skeletal tissue engineering and supplements for embryonic muscle growth. However, fine dose tuning and treatment period arranging are highly warranted as boron treatment over required concentrations and time might result in detrimental outcomes to myogenesis and myo-regeneration.

[The molecular mechanisms of curcuma wenyujin extract-mediated inhibitory effects on human esophageal carcinoma cells in vitro].

PubMed

Jing, Zhao; Zou, Hai-Zhou; Xu, Fang

2012-09-01

To study the molecular mechanisms of Curcuma Wenyujin extract-mediated inhibitory effects on human esophageal carcinoma cells. The Curcuma Wenyujin extract was obtained by supercritical carbon dioxide extraction. TE-1 cells were divided into 4 groups after adherence. 100 microL RMPI-1640 culture medium containing 0.1% DMSO was added in Group 1 as the control group. 100 microL 25, 50, and 100 mg/L Curcuma Wenyujin extract complete culture medium was respectively added in the rest 3 groups as the low, middle, and high dose Curcuma Wenyujin extract groups. The effects of different doses of Curcuma Wenyujin extract (25, 50, and 100 mg/L) on the proliferation of human esophageal carcinoma cell line TE-1 in vitro were analyzed by MTT assay. The gene expression profile was identified by cDNA microarrays in esophageal carcinoma TE-1 cells exposed to Curcuma Wenyujin extract for 48 h. The differential expression genes were further analyzed by Gene Ontology function analysis. Compared with the control group, MTT results showed that Curcuma Wenyujin extract significantly inhibited the proliferation of TE-1 cells in a dose-dependent manner (P<0.05). The expression level of 88 genes changed with significance, including 66 up-regulation genes and 22 down-regulation genes. Gene Ontology analysis indicated the genes coding for proteins was involved in signal transduction (6), cell cycle (8), apoptosis (14), and cell differentiation (10). The Curcuma Wenyujin extract could inhibit the growth of human esophageal carcinoma cell line TE-1 in vitro. The molecular mechanisms might be associated with regulating genes expressions at multi-levels.

Characterization of the role of Fhit in maintenance of genomic integrity following low dose radiation, in vivo and in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ya Wang

2010-05-31

The major goal of this study is to determine the effects of the Fhit pathway on low dose ({le} 0.1 Gy) ionizing radiation (IR)-induced genetic instability. Reduction of Fhit protein expression is observed in most solid tumors particularly in those tumors resulting from exposure to environmental carcinogens. Therefore, characterization of the role of the Fhit-dependent pathway in preventing low dose IR-induced genetic instability will provide useful parameters for evaluating the low dose IR-induced risk of mutagenesis and carcinogenesis. We pursued 3 specific aims to study our hypothesis that the Fhit-dependent pathways maintain genomic integrity through adjusting checkpoint response and repairmore » genes expression following low dose IR. Aim 1: Determine whether Fhit interaction with RPA is necessary for Fhit to affect the cellular response to low dose IR. We combined the approaches of in vitro (GST pull-down and site-directed mutagenesis) and in vivo (observing the co-localization and immunoprecipitation of Fhit and RPA in Fhit knock out mouse cells transfected with mutant Fhit which has lost ability to interact with RPA in vitro). Aim 2: Determine the role of genes whose expression is affected by Fhit in low dose irradiated cells. We analyzed the distinct signature of gene expression in low dose irradiated Fhit-/- cells compared with Fhit+/+ cells by combining microarray, gene transfection and siRNA approaches. Aim 3: Determine the role of Fhit in genetic susceptibility to low dose IR in vivo. We compared the gene mutation frequency and the fragile site stability in the cells isolated from the Fhit+/+ and Fhit-/- mice at 1.5 years following low dose IR. These results determine the role of the Fhit-dependent pathway in maintaining genomic integrity in vitro and in vivo, which provide a basis for choosing surrogate markers in the Fhit-dependent pathway to evaluate low dose IR-induced risk of mutagenesis and carcinogenesis.« less

Spatially Fractionated Radiation Induces Cytotoxicity and Changes in Gene Expression in Bystander and Radiation Adjacent Murine Carcinoma Cells

PubMed Central

Asur, Rajalakshmi S.; Sharma, Sunil; Chang, Ching-Wei; Penagaricano, Jose; Kommuru, Indira M.; Moros, Eduardo G.; Corry, Peter M.; Griffin, Robert J.

2012-01-01

Radiation-induced bystander effects have been extensively studied at low doses, since evidence of bystander induced cell killing and other effects on unirradiated cells were found to be predominant at doses up to 0.5 Gy. Therefore, few studies have examined bystander effects induced by exposure to higher doses of radiation, such as spatially fractionated radiation (GRID) treatment. In the present study, we evaluate the ability of GRID treatment to induce changes in GRID adjacent (bystander) regions, in two different murine carcinoma cell lines following exposure to a single irradiation dose of 10 Gy. Murine SCK mammary carcinoma cells and SCCVII squamous carcinoma cells were irradiated using a brass collimator to create a GRID pattern of nine circular fields 12 mm in diameter with a center-to-center distance of 18 mm. Similar to the typical clinical implementation of GRID, this is approximately a 50:50 ratio of direct and bystander exposure. We also performed experiments by irradiating separate cultures and transferring the medium to unirradiated bystander cultures. Clonogenic survival was evaluated in both cell lines to determine the occurrence of radiation-induced bystander effects. For the purpose of our study, we have defined bystander cells as GRID adjacent cells that received approximately 1 Gy scatter dose or unirradiated cells receiving conditioned medium from irradiated cells. We observed significant bystander killing of cells adjacent to the GRID irradiated regions compared to sham treated controls. We also observed bystander killing of SCK and SCCVII cells cultured in conditioned medium obtained from cells irradiated with 10 Gy. Therefore, our results confirm the occurrence of bystander effects following exposure to a high-dose of radiation and suggest that cell-to-cell contact is not required for these effects. In addition, the gene expression profile for DNA damage and cellular stress response signaling in SCCVII cells after GRID exposure was studied. The occurrence of GRID-induced bystander gene expression changes in significant numbers of DNA damage and cellular stress response signaling genes, providing molecular evidence for possible mechanisms of bystander cell killing. PMID:22559204

Effects of FVIII immunity on hepatocyte and hematopoietic stem cell–directed gene therapy of murine hemophilia A

PubMed Central

Lytle, Allison M; Brown, Harrison C; Paik, Na Yoon; Knight, Kristopher A; Wright, J Fraser; Spencer, H Trent; Doering, Christopher B

2016-01-01

Immune responses to coagulation factors VIII (FVIII) and IX (FIX) represent primary obstacles to hemophilia treatment. Previously, we showed that hematopoietic stem cell (HSC) retroviral gene therapy induces immune nonresponsiveness to FVIII in both naive and preimmunized murine hemophilia A settings. Liver-directed adeno-associated viral (AAV)-FIX vector gene transfer achieved similar results in preclinical hemophilia B models. However, as clinical immune responses to FVIII and FIX differ, we investigated the ability of liver-directed AAV-FVIII gene therapy to affect FVIII immunity in hemophilia A mice. Both FVIII naive and preimmunized mice were administered recombinant AAV8 encoding a liver-directed bioengineered FVIII expression cassette. Naive animals receiving high or mid-doses subsequently achieved near normal FVIII activity levels. However, challenge with adjuvant-free recombinant FVIII induced loss of FVIII activity and anti-FVIII antibodies in mid-dose, but not high-dose AAV or HSC lentiviral (LV) vector gene therapy cohorts. Furthermore, unlike what was shown previously for FIX gene transfer, AAV-FVIII administration to hemophilia A inhibitor mice conferred no effect on anti-FVIII antibody or inhibitory titers. These data suggest that functional differences exist in the immune modulation achieved to FVIII or FIX in hemophilia mice by gene therapy approaches incorporating liver-directed AAV vectors or HSC-directed LV. PMID:26909355

Final Report - Epigenetics of low dose radiation effects in an animal model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kovalchuk, Olga

This project sought mechanistic understanding of the epigenetic response of tissues as well as the consequences of those responses, when induced by low dose irradiation in a well-established model system (mouse). Based on solid and extensive preliminary data we investigated the molecular epigenetic mechanisms of in vivo radiation responses, particularly – effects of low, occupationally relevant radiation exposures on the genome stability and adaptive response in mammalian tissues and organisms. We accumulated evidence that low dose irradiation altered epigenetic profiles and impacted radiation target organs of the exposed animals. The main long-term goal was to dissect the epigenetic basis ofmore » induction of the low dose radiation-induced genome instability and adaptive response and the specific fundamental roles of epigenetic changes (i.e. DNA methylation, histone modifications and miRNAs) in their generation. We hypothesized that changes in global and regional DNA methylation, global histone modifications and regulatory microRNAs played pivotal roles in the generation and maintenance low-dose radiation-induced genome instability and adaptive response. We predicted that epigenetic changes influenced the levels of genetic rearrangements (transposone reactivation). We hypothesized that epigenetic responses from low dose irradiation were dependent on exposure regimes, and would be greatest when organisms are exposed in a protracted/fractionated manner: fractionated exposures > acute exposures. We anticipated that the epigenetic responses were correlated with the gene expression levels. Our immediate objectives were: • To investigate the exact nature of the global and locus-specific DNA methylation changes in the LDR exposed cells and tissues and dissect their roles in adaptive response • To investigate the roles of histone modifications in the low dose radiation effects and adaptive response • To dissect the roles of regulatory microRNAs and their targets in low dose radiation effects and adaptive response • To correlate the levels of epigenetic changes with genetic rearrangement levels and gene expression patterns. In sum, we determined the precise global and locus-specific DNA methylation patterns in the LDR-exposed cells and tissues of mice, and to correlated DNA methylation changes with the gene expression patterns and manifestations of genome instability. We also determined the alterations of global histone modification pattern in the LDR exposed tissues. Additionally, we established the nature of microRNAome changes in the LDR exposed tissue. In this study we for the first time found that LDR exposure caused profound tissue-specific epigenetic changes in the exposed tissues. We established that LDR exposure affect methylation of repetitive elements in the murine genome, causes changes in histone methylation, acetylation and phosphorylation. Importantly, we found that LDR causes profound and persistent effects on small RNA profiles and gene expression, and that miRNAs are excellent biomarkers of LDR exposure. Furthermore, we extended our analysis and studied LDR effects in rat tissues and human tissues and cell lines. There we also analyzed LDR-induced gene expression, DNA methylation and miRNA changes. Our datasets laid foundation for several new research projects aimed to understand molecular underpinnings of low dose radiation responses, and biological repercussions of low dose radiation effects and radiation carcinogenesis.« less

Carbon Heavy-ion Radiation Induced Biological effects on Oryza sativa L.

NASA Astrophysics Data System (ADS)

Zhang, Meng; Sun, Yeqing; Li, Xishan; Gong, Ning; Meng, Qingmei; Liu, Jiawei; Wang, Ting

2016-07-01

Large number of researches on rice after spaceflights indicated that rice was a favorable model organism to study biological effects induced by space radiation. The stimulative effect could often be found on rice seedlings after irradiation by low-dose energetic heavy-ion radiation. Spaceflight also could induce stimulative effect on kinds of seeds. To further understand the mechanism of low-dose radiation biological effects and the dose range, the germinated rice seeds which were irradiated by different doses of carbon heavy-ion (0, 0.02, 0.1, 0.2, 1, 2, 5, 10, 15 and 20Gy, LET=27.3keV/µm) were used as materials to study. By investigating the variation of rice phenotype under different doses, we found that 2Gy radiation dose was a dividing point of the phenotypic variation. Transmission electron microscopy was used to observe the variation of mitochondria, chloroplast, endoplasmic reticulum, ribosome and nucleus in mesophyll cell of rice apical meristem at 24 hours after radiation with different doses. The cells were not apparently physiologically damaged when the dose of radiation was less than 2Gy. The number of chloroplast did not change significantly, but the number of mitochondria was significantly increased, and gathered around in the chloroplast and endoplasmic reticulum; the obvious lesion of chloroplast and mitochondria were found at the mesophyll cells when radiation dose was higher than 2Gy. The mitochondria were swelling and appearing blurred crest. The chloroplast and mitochondrial mutation rate increased significantly (p<0.01). These phenomena showed that cell biological changes may be the reasons of the stimulation and inhibition effects with the boundary of 2Gy. Since mitochondrial was an important organelle involved in the antioxidative systems, its dysfunction could result in the increase of reactive oxygen species and lipid peroxidation. We found that the growth stimulation induced by low-dose radiation mainly occurred at three-leaf stage along with the increasing activity of antioxidase system and damages of lipid peroxidation. We also found that the relative expression of genes sdhb and aox1a which encode the key proteins in mitochondria changed differently after exposed to different doses of radiation, and the lower dose of the radiation could cause longer effect. The chlorophyll was an important organ of photosynthesis, its dysfunction could result in the phenotypic variation. We found that the chlorophyll fluorescence parameter Fv/Fm, the content of chlorophyll (including chlorophyll a, chlorophyll b and total chlorophyll) and both the relative expression of CP24 and its encoding gene lhcb6 changed significantly in different doses. The changes of the relative expression of CP24 and its encoding gene lhcb6 were completely opposite at the lower dose and agreed at the higher dose. The possible mechanisms of growth stimulation and inhibition effects induced by low and high dose radiations were discussed on multiple levels. Moreover, our findings were important to understand the spaceflight induced growth stimulation and inhibition effects of plant. Keywords: Heavy-ion radiation; Low dose; Stimulation effect; Inhibition effect; Rice.

GDF-15 gene expression alterations in human lymphoblastoid cells and peripheral blood lymphocytes following exposure to ionizing radiation

PubMed Central

Li, Shuang; Zhang, Qing-Zhao; Zhang, De-Qin; Feng, Jiang-Bin; Luo, Qun; Lu, Xue; Wang, Xin-Ru; Li, Kun-Peng; Chen, De-Qing; Mu, Xiao-Feng; Gao, Ling; Liu, Qing-Jie

2017-01-01

The identification of rapid, sensitive and high-throughput biomarkers is imperative in order to identify individuals harmed by radiation accidents, and accurately evaluate the absorbed doses of radiation. DNA microarrays have previously been used to evaluate the alterations in growth/differentiation factor 15 (GDF15) gene expression in AHH-1 human lymphoblastoid cells, following exposure to γ-rays. The present study aimed to characterize the relationship between the dose of ionizing radiation and the produced effects in GDF-15 gene expression in AHH-1 cells and human peripheral blood lymphocytes (HPBLs). GDF-15 mRNA and protein expression levels following exposure to γ-rays and neutron radiation were assessed by reverse transcription-quantitative polymerase chain reaction and western blot analysis in AHH-1 cells. In addition, alterations in GDF-15 gene expression in HPBLs following ex vivo irradiation were evaluated. The present results demonstrated that GDF-15 mRNA and protein expression levels in AHH-1 cells were significantly upregulated following exposure to γ-ray doses ranging between 1 and 10 Gy, regardless of the dose rate. A total of 48 h following exposure to neutron radiation, a dose-response relationship was identified in AHH-1 cells at γ-ray doses between 0.4 and 1.6 Gy. GDF-15 mRNA levels in HPBLs were significantly upregulated following exposure to γ-ray doses between 1 and 8 Gy, within 4–48 h following irradiation. These results suggested that significant time- and dose-dependent alterations in GDF-15 mRNA and protein expression occur in AHH-1 cells and HPBLs in the early phases following exposure to ionizing radiation. In conclusion, alterations in GDF-15 gene expression may have potential as a biomarker to evaluate radiation exposure. PMID:28440431

An in vitro evaluation of anti-aging effect of guluronic acid (G2013) based on enzymatic oxidative stress gene expression using healthy individuals PBMCs.

PubMed

Taeb, Mahsa; Mortazavi-Jahromi, Seyed Shahabeddin; Jafarzadeh, Abdollah; Mirzaei, Mohammad Reza; Mirshafiey, Abbas

2017-06-01

Aging is usually associated with increased levels of oxidants, and may result in damages caused by oxidative stress. There is a direct relationship between aging and increased incidence of inflammatory diseases. The present research intended to study the anti-aging and anti-inflammatory effects of the drug G2013 (guluronic acid) at low and high doses on the genes expression of a number of enzymes involved in oxidative stress (including SOD2, GPX1, CAT, GST, iNOS, and MPO) in peripheral blood mononuclear cells (PBMCs) of healthy individuals under in vitro conditions. Venous blood samples were taken from 20 healthy individuals, the PBMCs were isolated and their RNAs extracted and their cDNAs were synthesized, and the genes expression levels were measured using the qRT-PCR technique. Our results indicated that this drug could, at both low and high doses, significantly reduce the expression of the genes for SOD2, GPX1, CAT, and GST compared to the LPS group (p<0.0001). Moreover, it was noticed that the drug is able to significantly reduce gene expression levels at the high dose and at both doses (low and high), for iNOS and MPO compared to the LPS group (p<0.0001), respectively. The present research showed that G2013, as a novel NSAID drug with immunomodulatory properties, could modulate the expression levels of the genes for SOD2, GPX1, CAT, GST, iNOS, and MPO, to the level of healthy gene expression, and possibly it might reduce the pathological process of aging and age-related inflammatory diseases. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Mice heterozygous for the oxytocin receptor gene (Oxtr(+/-)) show impaired social behaviour but not increased aggression or cognitive inflexibility: evidence of a selective haploinsufficiency gene effect.

PubMed

Sala, M; Braida, D; Donzelli, A; Martucci, R; Busnelli, M; Bulgheroni, E; Rubino, T; Parolaro, D; Nishimori, K; Chini, B

2013-02-01

We characterised the behavioural phenotype of mice heterozygous (Oxtr(+/-)) for the oxytocin receptor gene (Oxtr) and compared it with that of Oxtr null mice (Oxtr(-/-)), which display autistic-like behaviours, including impaired sociability and preference for social novelty, impaired cognitive flexibility, and increased aggression. Similar to Oxtr(-/-) mice, the Oxtr(+/-) showed impaired sociability and preference for social novelty but, unlike the null genotype, their cognitive flexibility and aggression were normal. By autoradiography, Oxtr(+/-) mice were found to have approximately 50% fewer oxytocin receptors (OXTRs) in all of the examined brain regions. Thus, because a partial reduction in Oxtr gene expression is sufficient to compromise social behaviour, the Oxtr acts as a haploinsufficient gene. Furthermore, the inactivation of the Oxtr gene affects specific behaviours in a dose-dependent manner: social behaviour is sensitive to even a partial reduction in Oxtr gene expression, whereas defects in aggression and cognitive flexibility require the complete inactivation of the Oxtr gene to emerge. We then investigated the rescue of the Oxtr(+/-) social deficits by oxytocin (OT) and Thr(4)Gly(7)OT (TGOT) administered i.c.v. at different doses. TGOT was more potent than OT in rescuing sociability and social novelty in both genotypes. Furthermore, the TGOT doses that reverted impaired sociability and preference for social novelty in Oxtr(+/-) were lower than those required in Oxtr(-/-), thus suggesting that the rescue effect is mediated by OXTR in Oxtr(+/-) and by other receptors (presumably vasopressin V1a receptors) in Oxtr(-/-). In line with this, a low dose of the selective oxytocin antagonist desGlyDTyrOVT blocks the rescue effect of TGOT only in the Oxtr(+/-) genotype, whereas the less selective antagonist SR49059 blocks rescue in both genotypes. In conclusion, the Oxtr(+/-) mouse is a unique animal model for investigating how partial loss of the Oxtr gene impair social interactions, and for designing pharmacological rescue strategies. © 2012 British Society for Neuroendocrinology.

Green tea polyphenol (−)-epigallocatechin-3-gallate triggered hepatotoxicity in mice: Responses of major antioxidant enzymes and the Nrf2 rescue pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Dongxu; Wang, Yijun; Wan, Xiaochun

(−)-Epigallocatechin-3-gallate (EGCG), a constituent of green tea, has been suggested to have numerous health-promoting effects. On the other hand, high-dose EGCG is able to evoke hepatotoxicity. In the present study, we elucidated the responses of hepatic major antioxidant enzymes and nuclear factor erythroid 2-related factor 2 (Nrf2) rescue pathway to high-dose levels of EGCG in Kunming mice. At a non-lethal toxic dose (75 mg/kg, i.p.), repeated EGCG treatments markedly decreased the levels of superoxide dismutase, catalase, and glutathione peroxidase. As a rescue response, the nuclear distribution of Nrf2 was significantly increased; a battery of Nrf2-target genes, including heme oxygenase 1more » (HO1), NAD(P)H:quinone oxidoreductase 1 (NQO1), glutathione S-transferase (GST), and those involved in glutathione and thioredoxin systems, were all up-regulated. At the maximum tolerated dose (45 mg/kg, i.p.), repeated EGCG treatments did not disturb the major antioxidant defense. Among the above-mentioned genes, only HO1, NQO1, and GST genes were significantly but modestly up-regulated, suggesting a comprehensive and extensive activation of Nrf2-target genes principally occurs at toxic levels of EGCG. At a lethal dose (200 mg/kg, i.p.), a single EGCG treatment dramatically decreased not only the major antioxidant defense but also the Nrf2-target genes, demonstrating that toxic levels of EGCG are able to cause a biphasic response of Nrf2. Overall, the mechanism of EGCG-triggered hepatotoxicity involves suppression of major antioxidant enzymes, and the Nrf2 rescue pathway plays a vital role for counteracting EGCG toxicity. - Highlights: • EGCG at maximum tolerated dose does not disturb hepatic major antioxidant defense. • EGCG at maximum tolerated dose modestly upregulates hepatic Nrf2 target genes. • EGCG at toxic dose suppresses hepatic major antioxidant enzymes. • EGCG at non-lethal toxic dose pronouncedly activates hepatic Nrf2 rescue response. • EGCG at lethal dose substantially suppresses hepatic Nrf2 pathway.« less

A Study of the Differential Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Gene Expression Profiles of Stimulated Thp-1 Macrophages

PubMed Central

Allam-Ndoul, Bénédicte; Guénard, Frédéric; Barbier, Olivier; Vohl, Marie-Claude

2017-01-01

Background: An appropriate intake of omega-3 (n-3) fatty acids (FAs) such as eicosapentaenoic and docosahexaenoic acid (EPA/DHA) from marine sources is known to have anti-inflammatory effects. However, molecular mechanisms underlying their beneficial effects on health are not fully understood. The aim of the present study was to characterize gene expression profiles of THP-1 macrophages, incubated in either EPA or DHA and stimulated with lipopolysaccharide (LPS), a pro-inflammatory agent. Methods: THP-1 macrophages were incubated into 10, 50 and 75 µM of EPA or DHA for 24 h, and 100 nM of LPS was added to the culture media for 18 h. Total mRNA was extracted and gene expression examined by microarray analysis using Illumina Human HT-12 expression beadchips (Illumina). Results: Pathway analysis revealed that EPA and DHA regulate genes involved in cell cycle regulation, apoptosis, immune response and inflammation, oxidative stress and cancer pathways in a differential and dose-dependent manner. Conclusions: EPA and DHA appear to exert differential effects on gene expression in THP-1 macrophages. Specific effects of n-3 FAs on gene expression levels are also dose-dependent. PMID:28441337

Molecular dissection of the roles of the SOD genes in mammalian response to low dose irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eric Y. Chuang

2006-08-31

It has been long recognized that a significant fraction of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying enzymes may be even more prominent in the case of low-dose, low-LET irradiation, as the majority of genetic damage may be caused by secondary oxidative species. In this study we have attempted to decipher the roles of the superoxide dismutase (SOD) genes, which are responsible for detoxifying the superoxide anions. We used adenovirus vectors tomore » deliver RNA interference (RNAi or siRNA) technology to down-regulate the expression levels of the SOD genes. We have also over-expressed the SOD genes by use of recombinant adenovirus vectors. Cells infected with the vectors were then subjected to low dose γ-irradiation. Total RNA were extracted from the exposed cells and the expression of 9000 genes were profiled by use of cDNA microarrays. The result showed that low dose radiation had clear effects on gene expression in HCT116 cells. Both over-expression and down-regulation of the SOD1 gene can change the expression profiles of sub-groups of genes. Close to 200 of the 9000 genes examined showed over two-fold difference in expression under various conditions. Genes with changed expression pattern belong to many categories that include: early growth response, DNA-repair, ion transport, apoptosis, and cytokine response.« less

Identification of radiation response genes and proteins from mouse pulmonary tissues after high-dose per fraction irradiation of limited lung volumes.

PubMed

Jin, Hee; Jeon, Seulgi; Kang, Ga-Young; Lee, Hae-June; Cho, Jaeho; Lee, Yun-Sil

2017-02-01

The molecular effects of focal exposure of limited lung volumes to high-dose per fraction irradiation (HDFR) such as stereotactic body radiotherapy (SBRT) have not been fully characterized. In this study, we used such an irradiation system and identified the genes and proteins after HDFR to mouse lung, similar to those associated with human therapy. High focal radiation (90 Gy) was applied to a 3-mm volume of the left lung of C57BL6 mice using a small-animal stereotactic irradiator. As well as histological examination for lungs, a cDNA micro array using irradiated lung tissues and a protein array of sera were performed until 4 weeks after irradiation, and radiation-responsive genes and proteins were identified. For comparison, the long-term effects (12 months) of 20 Gy radiation wide-field dose to the left lung were also investigated. The genes ermap, epb4.2, cd200r3 (up regulation) and krt15, hoxc4, gdf2, cst9, cidec, and bnc1 (down-regulation) and the proteins of AIF, laminin, bNOS, HSP27, β-amyloid (upregulation), and calponin (downregulation) were identified as being responsive to 90 Gy HDFR. The gdf2, cst9, and cidec genes also responded to 20 Gy, suggesting that they are universal responsive genes in irradiated lungs. No universal proteins were identified in both 90 Gy and 20 Gy. Calponin, which was downregulated in protein antibody array analysis, showed a similar pattern in microarray data, suggesting a possible HDFR responsive serum biomarker that reflects gene alteration of irradiated lung tissue. These genes and proteins also responded to the lower doses of 20 Gy and 50 Gy HDFR. These results suggest that identified candidate genes and proteins are HDFR-specifically expressed in lung damage induced by HDFR relevant to SBRT in humans.

Role of Pharmacogenomics in the Management of Traditional and Novel Oral Anticoagulants

PubMed Central

Cavallari, Larisa H.; Shin, Jaekyu; Perera, Minoli A.

2013-01-01

Warfarin is the most commonly prescribed oral anticoagulant. However, it remains a difficult drug to manage mostly because of its narrow therapeutic index and wide interpatient variability in anticoagulant effects. Over the past decade, there has been substantial progress in our understanding of genetic contributions to variable warfarin response, particularly with regard to warfarin dose requirements. The genes encoding for cytochrome P450 (CYP) 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) are the major genetic determinants of warfarin pharmacokinetics and pharmacodynamics, respectively. Numerous studies have demonstrated significant contributions of these genes to warfarin dose requirements. The CYP2C9 gene has also been associated with bleeding risk with warfarin. The CYP4F2 gene influences vitamin K availability and makes minor contributions to warfarin dose requirements. Less is known about genes influencing warfarin response in African-American patients compared with other racial groups, but this is the focus of ongoing research. Several warfarin pharmacogenetic dosing algorithms and United States Food and Drug Administration–cleared genotyping tests are available for clinical use. Clinical trials are ongoing to determine the clinical utility and cost-effectiveness of genotype-guided warfarin dosing. Results from these trials will likely influence clinical uptake and third party payer reimbursement for genotype-guided warfarin therapy. There is still a lack of pharmacogenetic data for the newly approved oral anticoagulants, dabigatran and rivaroxaban, and with other oral anticoagulants in the research and development pipeline. These data, once known, could be of great importance as routine monitoring parameters for these agents are not available. PMID:22122181

Evaluation of a toxicogenomic approach to the local lymph node assay (LLNA).

PubMed

Boverhof, Darrell R; Gollapudi, B Bhaskar; Hotchkiss, Jon A; Osterloh-Quiroz, Mandy; Woolhiser, Michael R

2009-02-01

Genomic technologies have the potential to enhance and complement existing toxicology endpoints; however, assessment of these approaches requires a systematic evaluation including a robust experimental design with genomic endpoints anchored to traditional toxicology endpoints. The present study was conducted to assess the sensitivity of genomic responses when compared with the traditional local lymph node assay (LLNA) endpoint of lymph node cell proliferation and to evaluate the responses for their ability to provide insights into mode of action. Female BALB/c mice were treated with the sensitizer trimellitic anhydride (TMA), following the standard LLNA dosing regimen, at doses of 0.1, 1, or 10% and traditional tritiated thymidine ((3)HTdR) incorporation and gene expression responses were monitored in the auricular lymph nodes. Additional mice dosed with either vehicle or 10% TMA and sacrificed on day 4 or 10, were also included to examine temporal effects on gene expression. Analysis of (3)HTdR incorporation revealed TMA-induced stimulation indices of 2.8, 22.9, and 61.0 relative to vehicle with an EC(3) of 0.11%. Examination of the dose-response gene expression responses identified 9, 833, and 2122 differentially expressed genes relative to vehicle for the 0.1, 1, and 10% TMA dose groups, respectively. Calculation of EC(3) values for differentially expressed genes did not identify a response that was more sensitive than the (3)HTdR value, although a number of genes displayed comparable sensitivity. Examination of temporal responses revealed 1760, 1870, and 953 differentially expressed genes at the 4-, 6-, and 10-day time points respectively. Functional analysis revealed many responses displayed dose- and time-specific induction patterns within the functional categories of cellular proliferation and immune response, including numerous immunoglobin genes which were highly induced at the day 10 time point. Overall, these experiments have systematically illustrated the potential utility of genomic endpoints to enhance the LLNA and support further exploration of this approach through examination of a more diverse array of chemicals.

Effect of Chemical Mutagens and Carcinogens on Gene Expression Profiles in Human TK6 Cells

PubMed Central

Godderis, Lode; Thomas, Reuben; Hubbard, Alan E.; Tabish, Ali M.; Hoet, Peter; Zhang, Luoping; Smith, Martyn T.; Veulemans, Hendrik; McHale, Cliona M.

2012-01-01

Characterization of toxicogenomic signatures of carcinogen exposure holds significant promise for mechanistic and predictive toxicology. In vitro transcriptomic studies allow the comparison of the response to chemicals with diverse mode of actions under controlled experimental conditions. We conducted an in vitro study in TK6 cells to characterize gene expression signatures of exposure to 15 genotoxic carcinogens frequently used in European industries. We also examined the dose-responsive changes in gene expression, and perturbation of biochemical pathways in response to these carcinogens. TK6 cells were exposed at 3 dose levels for 24 h with and without S9 human metabolic mix. Since S9 had an impact on gene expression (885 genes), we analyzed the gene expression data from cells cultures incubated with S9 and without S9 independently. The ribosome pathway was affected by all chemical-dose combinations. However in general, no similar gene expression was observed among carcinogens. Further, pathways, i.e. cell cycle, DNA repair mechanisms, RNA degradation, that were common within sets of chemical-dose combination were suggested by clustergram. Linear trends in dose–response of gene expression were observed for Trichloroethylene, Benz[a]anthracene, Epichlorohydrin, Benzene, and Hydroquinone. The significantly altered genes were involved in the regulation of (anti-) apoptosis, maintenance of cell survival, tumor necrosis factor-related pathways and immune response, in agreement with several other studies. Similarly in S9+ cultures, Benz[a]pyrene, Styrene and Trichloroethylene each modified over 1000 genes at high concentrations. Our findings expand our understanding of the transcriptomic response to genotoxic carcinogens, revealing the alteration of diverse sets of genes and pathways involved in cellular homeostasis and cell cycle control. PMID:22723965

Dopamine Gene Profiling to Predict Impulse Control and Effects of Dopamine Agonist Ropinirole.

PubMed

MacDonald, Hayley J; Stinear, Cathy M; Ren, April; Coxon, James P; Kao, Justin; Macdonald, Lorraine; Snow, Barry; Cramer, Steven C; Byblow, Winston D

2016-07-01

Dopamine agonists can impair inhibitory control and cause impulse control disorders for those with Parkinson disease (PD), although mechanistically this is not well understood. In this study, we hypothesized that the extent of such drug effects on impulse control is related to specific dopamine gene polymorphisms. This double-blind, placebo-controlled study aimed to examine the effect of single doses of 0.5 and 1.0 mg of the dopamine agonist ropinirole on impulse control in healthy adults of typical age for PD onset. Impulse control was measured by stop signal RT on a response inhibition task and by an index of impulsive decision-making on the Balloon Analogue Risk Task. A dopamine genetic risk score quantified basal dopamine neurotransmission from the influence of five genes: catechol-O-methyltransferase, dopamine transporter, and those encoding receptors D1, D2, and D3. With placebo, impulse control was better for the high versus low genetic risk score groups. Ropinirole modulated impulse control in a manner dependent on genetic risk score. For the lower score group, both doses improved response inhibition (decreased stop signal RT) whereas the lower dose reduced impulsiveness in decision-making. Conversely, the higher score group showed a trend for worsened response inhibition on the lower dose whereas both doses increased impulsiveness in decision-making. The implications of the present findings are that genotyping can be used to predict impulse control and whether it will improve or worsen with the administration of dopamine agonists.

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints.

PubMed

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B; George, Kerry A; Cucinotta, Francis A

2016-01-01

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictions of the charge number and energy dependence of RBE's using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE's are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE's against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Comparisons of the resulting model parameters to those used in the NASA radiation quality factor function are discussed.

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

DOE PAGES

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B.; ...

2016-04-25

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictionsmore » of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Finally, we discuss comparisons of the resulting model parameters to those used in the NASA radiation quality factor function.« less

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B.

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictionsmore » of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Finally, we discuss comparisons of the resulting model parameters to those used in the NASA radiation quality factor function.« less

Novel oxytocin receptor variants in laboring women requiring high doses of oxytocin.

PubMed

Reinl, Erin L; Goodwin, Zane A; Raghuraman, Nandini; Lee, Grace Y; Jo, Erin Y; Gezahegn, Beakal M; Pillai, Meghan K; Cahill, Alison G; de Guzman Strong, Cristina; England, Sarah K

2017-08-01

Although oxytocin commonly is used to augment or induce labor, it is difficult to predict its effectiveness because oxytocin dose requirements vary significantly among women. One possibility is that women requiring high or low doses of oxytocin have variations in the oxytocin receptor gene. To identify oxytocin receptor gene variants in laboring women with low and high oxytocin dosage requirements. Term, nulliparous women requiring oxytocin doses of ≤4 mU/min (low-dose-requiring, n = 83) or ≥20 mU/min (high-dose-requiring, n = 104) for labor augmentation or induction provided consent to a postpartum blood draw as a source of genomic DNA. Targeted-amplicon sequencing (coverage >30×) with MiSeq (Illumina) was performed to discover variants in the coding exons of the oxytocin receptor gene. Baseline relevant clinical history, outcomes, demographics, and oxytocin receptor gene sequence variants and their allele frequencies were compared between low-dose-requiring and high-dose-requiring women. The Scale-Invariant Feature Transform algorithm was used to predict the effect of variants on oxytocin receptor function. The Fisher exact or χ 2 tests were used for categorical variables, and Student t tests or Wilcoxon rank sum tests were used for continuous variables. A P value < .05 was considered statistically significant. The high-dose-requiring women had greater rates of obesity and diabetes and were more likely to have undergone labor induction and required prostaglandins. High-dose-requiring women were more likely to undergo cesarean delivery for first-stage arrest and less likely to undergo cesarean delivery for nonreassuring fetal status. Targeted sequencing of the oxytocin receptor gene in the total cohort (n = 187) revealed 30 distinct coding variants: 17 nonsynonymous, 11 synonymous, and 2 small structural variants. One novel variant (A243T) was found in both the low- and high-dose-requiring groups. Three novel variants (Y106H, A240_A249del, and P197delfs*206) resulting in an amino acid substitution, loss of 9 amino acids, and a frameshift stop mutation, respectively, were identified only in low-dose-requiring women. Nine nonsynonymous variants were unique to the high-dose-requiring group. These included 3 known variants (R151C, G221S, and W228C) and 6 novel variants (M133V, R150L, H173R, A248V, G253R, and I266V). Of these, R150L, R151C, and H173R were predicted by Scale-Invariant Feature Transform algorithm to damage oxytocin receptor function. There was no statistically significant association between the numbers of synonymous and nonsynonymous substitutions in the patient groups. Obesity, diabetes, and labor induction were associated with the requirement for high doses of oxytocin. We did not identify significant differences in the prevalence of oxytocin receptor variants between low-dose-requiring and high-dose-requiring women, but novel oxytocin receptor variants were enriched in the high-dose-requiring women. We also found 3 oxytocin receptor variants (2 novel, 1 known) that were predicted to damage oxytocin receptor function and would likely increase an individual's risk for requiring a high oxytocin dose. Further investigation of oxytocin receptor variants and their effects on protein function will inform precision medicine in pregnant women. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Course-, dose-, and stage-dependent toxic effects of prenatal dexamethasone exposure on fetal articular cartilage development.

PubMed

Chen, Ze; Zhao, Zhe; Li, Yunzepeng; Zhang, Xingyu; Li, Bin; Chen, Liaobin; Wang, Hui

2018-04-01

Dexamethasone, a synthetic long-acting glucocorticoid, is routinely used for treating mothers at risk for preterm delivery. However, intrauterine overexposure to glucocorticoids induces low birth weight and cartilage dysplasia in offspring. Also, the "critical window" and safe dose of this treatment are largely unknown. This study investigated the course-, dose-, and stage-dependent toxic effects and the possible mechanisms of prenatal dexamethasone exposure (PDE) on fetal development and articular cartilage development. Pregnant mice (C57BL/6) received subcutaneous injection of dexamethasone (0.8 mg/kg d) once on gestational day (GD) 15 or once a day from GD 15 to 17, or received various doses of dexamethasone (0, 0.2, 0.8, and 1.2 mg/kg d) on GD 15-17, or received dexamethasone (0.8 mg/kg d) at early stage (GD 12-14) or late stage of pregnancy (GD 15-17). Offspring's knee joints were harvested at birth for morphological analyses and detection of gene expression. Repeated PDE significantly suppressed fetal and articular cartilage development, which were characterized by decreased body weight and body length, coarse articular cartilage surfaces, and reduced gene and protein expression of Col2a1 and aggrecan. For those newborns treated with repeated PDE at different doses, the toxic effects on fetal and articular cartilage development were observed at doses of 0.8 and 1.2 mg/kg d, whereas no obvious toxic effects were observed at the dose of 0.2 mg/kg d. Moreover, PDE at 0.8 mg/kg d during the early embryonic stage induced stronger toxic effects on fetal and articular cartilage development, compared with PDE during the late embryonic stage. Detection of gene expression showed that the TGFβ signaling pathway in the articular cartilage was down-regulated after PDE. Taken together, PDE induces fetal developmental toxicity and articular cartilage developmental toxicity in a course-, dose-, and stage-dependent manner. Copyright © 2018 Elsevier B.V. All rights reserved.

Embryotoxic and pharmacologic potency ranking of six azoles in the rat whole embryo culture by morphological and transcriptomic analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dimopoulou, Myrto, E-mail: myrto.dimopoulou@wur.nl

Differential gene expression analysis in the rat whole embryo culture (WEC) assay provides mechanistic insight into the embryotoxicity of test compounds. In our study, we hypothesized that comparative analysis of the transcriptomes of rat embryos exposed to six azoles (flusilazole, triadimefon, ketoconazole, miconazole, difenoconazole and prothioconazole) could lead to a better mechanism-based understanding of their embryotoxicity and pharmacological action. For evaluating embryotoxicity, we applied the total morphological scoring system (TMS) in embryos exposed for 48 h. The compounds tested showed embryotoxicity in a dose-response fashion. Functional analysis of differential gene expression after 4 h exposure at the ID{sub 10} (effectivemore » dose for 10% decreased TMS), revealed the sterol biosynthesis pathway and embryonic development genes, dominated by genes in the retinoic acid (RA) pathway, albeit in a differential way. Flusilazole, ketoconazole and triadimefon were the most potent compounds affecting the RA pathway, while in terms of regulation of sterol function, difenoconazole and ketoconazole showed the most pronounced effects. Dose-dependent analysis of the effects of flusilazole revealed that the RA pathway related genes were already differentially expressed at low dose levels while the sterol pathway showed strong regulation at higher embryotoxic doses, suggesting that this pathway is less predictive for the observed embryotoxicity. A similar analysis at the 24-hour time point indicated an additional time-dependent difference in the aforementioned pathways regulated by flusilazole. In summary, the rat WEC assay in combination with transcriptomics could add a mechanistic insight into the embryotoxic potency ranking and pharmacological mode of action of the tested compounds. - Highlights: • Embryonic exposure to azoles revealed concentration-dependent malformations. • Transcriptomics could enhance the mechanistic knowledge of embryotoxicants. • Retinoic acid gene set identifies early embryotoxic responses to azoles. • Toxic versus pharmacologic potency determines functional efficacy.« less

The early effects of stavudine compared with tenofovir on adipocyte gene expression, mitochondrial DNA copy number and metabolic parameters in South African HIV-infected patients: a randomized trial.

PubMed

Menezes, C N; Duarte, R; Dickens, C; Dix-Peek, T; Van Amsterdam, D; John, M-A; Ive, P; Maskew, M; Macphail, P; Fox, M P; Raal, F; Sanne, I; Crowther, N J

2013-04-01

Stavudine is being phased out because of its mitochondrial toxicity and tenofovir (TDF) is recommended as part of first-line highly active antiretroviral therapy (HAART) in South Africa. A prospective, open-label, randomized controlled trial comparing standard- and low-dose stavudine with TDF was performed to assess early differences in adipocyte mtDNA copy number, gene expression and metabolic parameters in Black South African HIV-infected patients. Sixty patients were randomized 1:1:1 to either standard-dose (30-40 mg) or low-dose (20-30 mg) stavudine or TDF (300 mg) each combined with lamivudine and efavirenz. Subcutaneous fat biopsies were obtained at weeks 0 and 4. Adipocyte mtDNA copies/cell and gene expression were measured using quantitative polymerase chain reaction (qPCR). Markers of inflammation and lipid and glucose metabolism were also assessed. A 29% and 32% decrease in the mean mtDNA copies/cell was noted in the standard-dose (P < 0.05) and low-dose stavudine (P < 0.005) arms, respectively, when compared with TDF at 4 weeks. Nuclear respiratory factor-1 (NRF1) and mitochondrial cytochrome B (MTCYB) gene expression levels were affected by stavudine, with a significantly (P < 0.05) greater fall in expression observed with the standard, but not the low dose compared with TDF. No significant differences were observed in markers of inflammation and lipid and glucose metabolism. These results demonstrate early mitochondrial depletion among Black South African patients receiving low and standard doses of stavudine, with preservation of gene expression levels, except for NRF1 and MTCYB, when compared with patients on TDF. © 2012 British HIV Association.

Progress toward a non-viral gene therapy protocol for the treatment of anemia

PubMed Central

Sebestyén, Magdolna G.; Hegge, Julia O.; Noble, Mark A.; Lewis, David L.; Herweijer, Hans; Wolff, Jon A.

2008-01-01

Anemia frequently accompanies chronic diseases such as progressive renal failure, AIDS and cancer. Patients are currently treated with erythropoietin (EPO) replacement therapy using various recombinant human EPO protein formulations. Although this treatment is effective, gene therapy could be more economical and more convenient for the long-term management of the disease. The objective of this study was to develop a naked DNA-based gene therapy protocol that could fill this need. The hydrodynamic limb vein technology has been shown to be an effective and safe procedure for delivering naked plasmid DNA (pDNA) into the skeletal muscles of the limb. Using this method, we addressed the major challenge of an EPO-based gene therapy of anemia: maintaining stable, long-term expression at a level that sufficiently promotes erythropoiesis without leading to polycythemia. The results of our study using a rat anemia model provide proof of principle that repeated delivery of small pDNA doses has an additive effect and can gradually lead to the correction of anemia without triggering excessive hemopoiesis. This simple method provides an alternative approach for regulating EPO expression. EPO expression was also proportional to the injected pDNA dose in non-human primates. In addition, long-term (over 450 days) expression was obtained after delivering rhesus EPO cDNA under the transcriptional control of the muscle-specific MCK promoter. In conclusion, these data suggest that the repeated delivery of small doses of EPO expressing pDNA into skeletal muscle is a promising, clinically viable approach to alleviate the symptoms of anemia. Overview summary We delivered various EPO-expressing naked pDNA constructs into the skeletal muscles of the limb by the minimally invasive, hydrodynamic limb vein (HLV) procedure. Serum EPO concentrations and the physiological response were pDNA dose-dependent both in rats and rhesus monkeys. The kinetics and longevity of expression were promoter-dependent. The mouse MCK promoter provided stable expression for well over a year, while the effect of the CMV promoter construct lasted only for 5–7 months. By using repeated, small-dose pDNA injections in a rat anemia model, EPO expression was controlled at the most fundamental level of the delivered gene dose. Our results suggest that this non-viral gene therapy approach provides safe and long-term solution for the treatment of chronic anemia and that it can be tailored to the individual needs of the patient. PMID:17376007

Oral MSG administration alters hepatic expression of genes for lipid and nitrogen metabolism in suckling piglets.

PubMed

Chen, Gang; Zhang, Jun; Zhang, Yuzhe; Liao, Peng; Li, Tiejun; Chen, Lixiang; Yin, Yulong; Wang, Jinquan; Wu, Guoyao

2014-01-01

This experiment was conducted to investigate the effects of oral administration of monosodium glutamate (MSG) on expression of genes for hepatic lipid and nitrogen metabolism in piglets. A total of 24 newborn pigs were assigned randomly into one of four treatments (n = 6/group). The doses of oral MSG administration, given at 8:00 and 18:00 to sow-reared piglets between 0 and 21 days of age, were 0 (control), 0.06 (low dose), 0.5 (intermediate dose), and 1 (high dose) g/kg body weight/day. At the end of the 3-week treatment, serum concentrations of total protein and high-density lipoprotein cholesterol in the intermediate dose group were elevated than those in the control group (P < 0.05). Hepatic mRNA levels for fatty acid synthase, acetyl-coA carboxylase, insulin-like growth factor-1, glutamate-oxaloacetate transaminase, and glutamate-pyruvate transaminase were higher in the middle-dose group (P < 0.05), compared with the control group. MSG administration did not affect hepatic mRNA levels for hormone-sensitive lipase or carnitine palmitoyl transferase-1. We conclude that oral MSG administration alters hepatic expression of certain genes for lipid and nitrogen metabolism in suckling piglets.

Defence strategies and antibiotic resistance gene abundance in enterococci under stress by exposure to low doses of peracetic acid.

PubMed

Turolla, Andrea; Sabatino, Raffaella; Fontaneto, Diego; Eckert, Ester M; Colinas, Noemi; Corno, Gianluca; Citterio, Barbara; Biavasco, Francesca; Antonelli, Manuela; Mauro, Alessandro; Mangiaterra, Gianmarco; Di Cesare, Andrea

2017-10-01

Peracetic acid (PAA) is an organic compound used efficiently as disinfectant in wastewater treatments. Yet, at low doses it may cause selection; thus, the effect of low doses of PAA on Enterococcus faecium as a proxy of human-related microbial waste was evaluated. Bacteria were treated with increasing doses of PAA (from 0 to 25 mg L -1 min) and incubated in regrowth experiments under non-growing, limiting conditions and under growing, favorable conditions. The changes in bacterial abundance, in bacterial phenotype (number and composition of small cell clusters), and in the abundance of an antibiotic resistance gene (ARG) was evaluated. The experiment demonstrated that the selected doses of PAA efficiently removed enterococci, and induced a long-lasting effect after PAA inactivation. The relative abundance of small clusters increased during the experiment when compared with that of the inoculum. Moreover, under growing favorable conditions the relative abundance of small clusters decreased and the number of cells per cluster increased with increasing PAA doses. A strong stability of the measured ARG was found, not showing any effect during the whole experiment. The results demonstrated the feasibility of low doses of PAA to inactivate bacteria. However, the stress induced by PAA disinfection promoted a bacterial adaptation, even if potentially without affecting the abundance of the ARG. Copyright © 2017 Elsevier Ltd. All rights reserved.

Arsenic as an Endocrine Disruptor: Arsenic Disrupts Retinoic Acid Receptor–and Thyroid Hormone Receptor–Mediated Gene Regulation and Thyroid Hormone–Mediated Amphibian Tail Metamorphosis

PubMed Central

Davey, Jennifer C.; Nomikos, Athena P.; Wungjiranirun, Manida; Sherman, Jenna R.; Ingram, Liam; Batki, Cavus; Lariviere, Jean P.; Hamilton, Joshua W.

2008-01-01

Background Chronic exposure to excess arsenic in drinking water has been strongly associated with increased risks of multiple cancers, diabetes, heart disease, and reproductive and developmental problems in humans. We previously demonstrated that As, a potent endocrine disruptor at low, environmentally relevant levels, alters steroid signaling at the level of receptor-mediated gene regulation for all five steroid receptors. Objectives The goal of this study was to determine whether As can also disrupt gene regulation via the retinoic acid (RA) receptor (RAR) and/or the thyroid hormone (TH) receptor (TR) and whether these effects are similar to previously observed effects on steroid regulation. Methods and results Human embryonic NT2 or rat pituitary GH3 cells were treated with 0.01–5 μM sodium arsenite for 24 hr, with or without RA or TH, respectively, to examine effects of As on receptor-mediated gene transcription. At low, noncytotoxic doses, As significantly altered RAR-dependent gene transcription of a transfected RAR response element–luciferase construct and the native RA-inducible cytochrome P450 CYP26A gene in NT2 cells. Likewise, low-dose As significantly altered expression of a transfected TR response element–luciferase construct and the endogenous TR-regulated type I deiodinase (DIO1) gene in a similar manner in GH3 cells. An amphibian ex vivo tail metamorphosis assay was used to examine whether endocrine disruption by low-dose As could have specific pathophysiologic consequences, because tail metamorphosis is tightly controlled by TH through TR. TH-dependent tail shrinkage was inhibited in a dose-dependent manner by 0.1– 4.0 μM As. Conclusions As had similar effects on RAR- and TR-mediated gene regulation as those previously observed for the steroid receptors, suggesting a common mechanism or action. Arsenic also profoundly affected a TR-dependent developmental process in a model animal system at very low concentrations. Because RAR and TH are critical for both normal human development and adult function and their dysregulation is associated with many disease processes, disruption of these hormone receptor–dependent processes by As is also potentially relevant to human developmental problems and disease risk. PMID:18288313

Differentially Expressed Genes Associated with Low-Dose Gamma Radiation

NASA Astrophysics Data System (ADS)

Hegyesi, Hargita; Sándor, Nikolett; Schilling, Boglárka; Kis, Enikő; Lumniczky, Katalin; Sáfrány, Géza

We have studied low dose radiation induced gene expression alterations in a primary human fibroblast cell line using Agilent's whole human genome microarray. Cells were irradiated with 60Co γ-rays (0; 0.1; 0.5 Gy) and 2 hours later total cellular RNA was isolated. We observed differential regulation of approximately 300-500 genes represented on the microarray. Of these, 126 were differentially expressed at both doses, among them significant elevation of GDF-15 and KITLG was confirmed by qRT-PCR. Based on the transcriptional studies we selected GDF-15 to assess its role in radiation response, since GDF-15 is one of the p53 gene targets and is believed to participate in mediating p53 activities. First we confirmed gamma-radiation induced dose-dependent changes in GDF-15 expression by qRT-PCR. Next we determined the effect of GDF-15 silencing on radiosensitivity. Four GDF-15 targeting shRNA expressing lentiviral vectors were transfected into immortalized human fibroblast cells. We obtained efficient GDF-15 silencing in one of the four constructs. RNA interference inhibited GDF-15 gene expression and enhanced the radiosensitivity of the cells. Our studies proved that GDF-15 plays an essential role in radiation response and may serve as a promising target in radiation therapy.

Radiation Dose-Rate Effects on Gene Expression in a Mouse Biodosimetry Model

PubMed Central

Paul, Sunirmal; Smilenov, Lubomir B.; Elliston, Carl D.; Amundson, Sally A.

2015-01-01

In the event of a nuclear accident or radiological terrorist attack, there will be a pressing need for biodosimetry to triage a large, potentially exposed population and to assign individuals to appropriate treatment. Exposures from fallout are likely, resulting in protracted dose delivery that would, in turn, impact the extent of injury. Biodosimetry approaches that can distinguish such low-dose-rate (LDR) exposures from acute exposures have not yet been developed. In this study, we used the C57BL/6 mouse model in an initial investigation of the impact of low-dose-rate delivery on the transcriptomic response in blood. While a large number of the same genes responded to LDR and acute radiation exposures, for many genes the magnitude of response was lower after LDR exposures. Some genes, however, were differentially expressed (P < 0.001, false discovery rate < 5%) in mice exposed to LDR compared with mice exposed to acute radiation. We identified a set of 164 genes that correctly classified 97% of the samples in this experiment as exposed to acute or LDR radiation using a support vector machine algorithm. Gene expression is a promising approach to radiation biodosimetry, enhanced greatly by this first demonstration of its potential for distinguishing between acute and LDR exposures. Further development of this aspect of radiation biodosimetry, either as part of a complete gene expression biodosimetry test or as an adjunct to other methods, could provide vital triage information in a mass radiological casualty event. PMID:26114327

Amlodipine at high dose increases preproendothelin-1 expression in the ventricles and aorta of normotensive rats.

PubMed

Krenek, Peter; Morel, Nicole; Kyselovic, Jan; Wibo, Maurice

2004-04-01

High doses of dihydropyridine calcium channel blockers can activate the sympathetic nervous system and the renin-angiotensin system. Both noradrenaline and angiotensin II stimulate preproendothelin-1 gene expression, yet the effects of high doses of dihydropyridines on preproendothelin-1 expression in vivo remain unknown. To investigate the effects of high doses of dihydropyridines on preproendothelin-1 expression in the ventricles and aorta of normotensive rats. Sprague-Dawley rats were treated with amlodipine 5 or 20 mg/kg per day (Amlo 5 or Amlo 20) in drinking water for 5 days or 5 weeks. Systolic blood pressure and heart rate were measured by tail-cuff plethysmography. Gene expression was examined by reverse transcriptase polymerase chain reaction. Amlo 5 increased heart rate during the first week only and had no effect on blood pressure and ventricular weight and gene expression. Amlo 20 reduced blood pressure transiently and increased heart rate consistently. It did not change relative left ventricular weight (corrected for body weight) after 5 days, but increased it after 5 weeks; it increased relative right ventricular weight at both time points. Aorta weight (mg/mm) was decreased after 5 weeks of treatment with both dosages of amlodipine. Preproendothelin-1 mRNA levels were increased by Amlo 20 in the ventricles and aorta and, concomitantly, renin mRNA was increased in the kidney. Less consistently, interleukin-6 mRNA also increased in ventricles, whereas cardiotrophin-1 mRNA remained unchanged. The sensitivity of isolated aorta to the contractile effect of noradrenaline was decreased by Amlo 5, but not by Amlo 20. In Sprague-Dawley rats, high-dose amlodipine, while promoting neurohormonal activation, induced overexpression of preproendothelin-1 mRNA in the ventricles and aorta. Endothelin-1 overexpression could contribute to the lack of inhibitory effect of high-dose amlodipine on ventricular mass in normotensive rats.

Low-dose decitabine enhances the effect of PD-1 blockade in colorectal cancer with microsatellite stability by re-modulating the tumor microenvironment.

PubMed

Yu, Ganjun; Wu, Yanfeng; Wang, Wenying; Xu, Jia; Lv, Xiaoping; Cao, Xuetao; Wan, Tao

2018-04-05

PD-1 blockade has demonstrated impressive clinical outcomes in colorectal cancers that have high microsatellite instability. However, the therapeutic efficacy for patients with tumors with low microsatellite instability or stable microsatellites needs further improvement. Here, we have demonstrated that low-dose decitabine could increase the expression of immune-related genes such as major histocompatibility complex genes and cytokine-related genes as well as the number of lymphocytes at the tumor site in CT26 colorectal cancer-bearing mice. A more significant inhibition of tumor growth and a prolongation of survival were observed in the CT26 mouse model after treatment with a combination of PD-1 blockade and decitabine than in mice treated with decitabine or PD-1 blockade alone. The anti-tumor effect of the PD-1 blockade was enhanced by low-dose decitabine. The results of RNA sequencing and whole-genome bisulfite sequencing of decitabine-treated CT26 cells and tumor samples with microsatellite stability from the patient tumor-derived xenograft model have shown that many immune-related genes, including antigen-processing and antigen-presenting genes, were upregulated, whereas the promoter demethylation was downregulated after decitabine exposure. Therefore, decitabine-based tumor microenvironment re-modulation could improve the effect of the PD-1 blockade. The application of decitabine in PD-1 blockade-based immunotherapy may elicit more potent immune responses, which can provide clinical benefits to the colorectal cancer patients with low microsatellite instability or stable microsatellites.

Effect of methapyrilene hydrochloride on hepatic intracellular iron metabolism in vivo and in vitro.

PubMed

Kindrat, Iryna; Dreval, Kostiantyn; Shpyleva, Svitlana; Tryndyak, Volodymyr; de Conti, Aline; Mudalige, Thilak K; Chen, Tao; Erstenyuk, Anna M; Beland, Frederick A; Pogribny, Igor P

2017-11-05

The liver, a central detoxification organ and main regulator of systemic iron homeostasis, is prone to damage by xenobiotics. In the present study, we investigated the effect of the hepatotoxicant and hepatocarcinogen methapyrilene hydrochloride on iron metabolism in rat liver in a repeat-dose in vivo toxicity study and in human HepaRG cells in vitro. Treatment of male Fischer 344 (F344) rats with methapyrilene at doses 40 and 80mg/kg body weight (bw)/day by gavage for 6 weeks resulted in changes in the expression of classic hepatotoxicity-related marker genes and iron homeostasis-related genes, especially a prominent, dose-dependent down-regulation of the transferrin (Tf) gene and an up-regulation of the ferritin, light chain (Ftl) gene. A decrease in the level of TF and an increase in the level of FTL also occurred in methapyrilene-treated differentiated HepaRG cells, indicating the existence of interspecies and in vitro-in vivo similarities in the disturbance of cellular iron homeostasis upon liver injury. In contrast, there was minimal overlap in the expression of liver toxicity-marker genes in the livers of rats and in HepaRG cells treated with methapyrilene. Importantly, the decrease of transferrin at mRNA and protein levels occurred after the treatment with a low dose of methapyrilene that exhibited minimal cytotoxicity. These results demonstrate the significance of the dysregulation of hepatic iron metabolism in the pathogenesis and mechanism of chemical-induced liver toxicity and suggest that these changes may be sensitive and useful indicators of potentially hepatotoxic chemicals. Published by Elsevier B.V.

Lysine acetylsalicylate decreases proliferation and extracellular matrix gene expression rate in keloid fibroblasts in vitro.

PubMed

Petri, Jean-Bernhard; Haustein, Uwe-Frithjof

2002-01-01

In genetically predisposed individuals keloids are formed as benign collagenous tumors. The purpose of this study was to investigate whether the proliferation and matrix gene expression of keloid fibroblasts is differently influenced by the anti-inflammatory active drug lysine acetylsalicylate (LAS) when compared to normal skin fibroblasts in vitro. Normal skin and keloid fibroblasts derived from human donors were compared. Excessive scarring and the formation of keloids are (at least in part) due to an overproduction of collagen types I and III. The results show a significant dose-dependent anti-proliferative effect of lysine acetylsalicylate. At the level of gene expression we observed a pronounced inhibitory effect of LAS on procollagen I and III mRNA synthesis, whereas matrix metalloproteinase 1 and tissue inhibitor of metalloproteinases 1 were not altered. Further clinical studies are planned to evaluate these effects of a high-dose treatment of keloids with LAS.

Effects of aqueous extract of Arctium lappa L. roots on serum lipid metabolism.

PubMed

Hou, Bo; Wang, Wencheng; Gao, Hui; Cai, Shanglang; Wang, Chunbo

2018-01-01

Objective To identify potential genes that may be involved in lipid metabolism in rats after treatment with aqueous extract of Arctium lappa L (burdock). Methods Rats were randomly divided into six groups: (i) control (standard diet); (ii) model group (high-fat diet only); (iii) high-fat diet and low-dose aqueous burdock root extract (2 g/kg); (iv) high-fat diet and moderate-dose aqueous burdock root extract (4 g/kg); (v) high-fat diet and high-dose aqueous burdock root extract (8 g/kg); and (vi) a positive control group exposed to a high-fat diet and simvastatin (10 mg/kg). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed to find the potential candidate genes involved in the modulation of blood lipids by treatment with aqueous burdock root extract. Results Burdock root extract reduced body weight and cholesterol levels in rats. KEGG analysis revealed 113 genes that were involved in metabolic pathways. Of these, 27 potential genes associated with blood lipid metabolism were identified. Conclusions Aqueous extract of burdock root reduced body weight and cholesterol in rats, possibly by modulating the differential expression of genes.

[Toxic effect of trichloroethylene on liver cells with CYP3A4 gene defect].

PubMed

Liao, R Y; Liu, S

2016-06-20

To investigate the toxic effect of trichloroethylene on liver cells with CYP3A4 gene defect. The normal human liver cells (L02 cells) and liver cells with CYP3A4 gene defect were exposed to trichloroethylene at different doses (0.0, 0.4, 0.8, 1.6, 3.2, and 6.4 mmol/L). CCK8 assay and RT-qPCR were used to measure cell viability and changes in the expression of apoptosis genes and oncogenes. After being exposed to trichloroethylene at doses of 1.6, 3.2, and 6.4 mmol/L, the liver cells with CYP3A4 gene defect showed significantly higher cell viability than L02 cells (0.91±0.06/0.89±0.05/0.85±0.07 vs 0.80±0.04/0.73±0.06/0.67±0.07, P<0.05). The L02 cells in the 0.8~3.2 mmol/L trichloroethylene groups showed significant increases in the expression of the apoptosis genes caspase-3, caspase-8, and caspase-9 (P<0.05) , as well as the oncogenes c-myc, c-fos, and k-ras (P<0.05). Compared with the L02 cells, the cells with CYP3A4 gene defect showed significant reductions in the expression of the apoptosis genes caspase-3, caspase-8, and caspase-9 and the oncogenes c-myc, c-fos, and k-ras (P<0.05). Trichloroethylene exposure has a less effect on the expression of apoptosis genes and oncogenes in liver cells with CYP3A4 gene defect than in normal human liver cells, suggesting that CYP3A4 gene defect reduces the inductive effect of trichloroethylene on apoptosis genes and oncogenes.

Concordance of transcriptional and apical benchmark dose levels for conazole-induced liver effects in mice.

PubMed

Bhat, Virunya S; Hester, Susan D; Nesnow, Stephen; Eastmond, David A

2013-11-01

The ability to anchor chemical class-based gene expression changes to phenotypic lesions and to describe these changes as a function of dose and time informs mode-of-action determinations and improves quantitative risk assessments. Previous global expression profiling identified a 330-probe cluster differentially expressed and commonly responsive to 3 hepatotumorigenic conazoles (cyproconazole, epoxiconazole, and propiconazole) at 30 days. Extended to 2 more conazoles (triadimefon and myclobutanil), the present assessment encompasses 4 tumorigenic and 1 nontumorigenic conazole. Transcriptional benchmark dose levels (BMDL(T)) were estimated for a subset of the cluster with dose-responsive behavior and a ≥ 5-fold increase or decrease in signal intensity at the highest dose. These genes primarily encompassed CAR/RXR activation, P450 metabolism, liver hypertrophy- glutathione depletion, LPS/IL-1-mediated inhibition of RXR, and NRF2-mediated oxidative stress pathways. Median BMDL(T) estimates from the subset were concordant (within a factor of 2.4) with apical benchmark doses (BMDL(A)) for increased liver weight at 30 days for the 5 conazoles. The 30-day median BMDL(T) estimates were within one-half order of magnitude of the chronic BMDLA for hepatocellular tumors. Potency differences seen in the dose-responsive transcription of certain phase II metabolism, bile acid detoxification, and lipid oxidation genes mirrored each conazole's tumorigenic potency. The 30-day BMDL(T) corresponded to tumorigenic potency on a milligram per kilogram day basis with cyproconazole > epoxiconazole > propiconazole > triadimefon > myclobutanil (nontumorigenic). These results support the utility of measuring short-term gene expression changes to inform quantitative risk assessments from long-term exposures.

Chronic exposure to low doses of pharmaceuticals disturbs the hepatic expression of circadian genes in lean and obese mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anthérieu, Sébastien; Le Guillou, Dounia; Coulouarn, Cédric

Drinking water can be contaminated with pharmaceuticals. However, it is uncertain whether this contamination can be harmful for the liver, especially during obesity. Hence, the goal of our study was to determine whether chronic exposure to low doses of pharmaceuticals could have deleterious effects on livers of lean and obese mice. To this end, lean and ob/ob male mice were treated for 4 months with a mixture of 11 drugs provided in drinking water at concentrations ranging from 10 to 10{sup 6} ng/l. At the end of the treatment, some liver and plasma abnormalities were observed in ob/ob mice treatedmore » with the cocktail containing 10{sup 6} ng/l of each drug. For this dosage, a gene expression analysis by microarray showed altered expression of circadian genes (e.g. Bmal1, Dbp, Cry1) in lean and obese mice. RT-qPCR analyses carried out in all groups of animals confirmed that expression of 8 different circadian genes was modified in a dose-dependent manner. For some genes, a significant modification was observed for dosages as low as 10{sup 2}–10{sup 3} ng/l. Drug mixture and obesity presented an additive effect on circadian gene expression. These data were validated in an independent study performed in female mice. Thus, our study showed that chronic exposure to trace pharmaceuticals disturbed hepatic expression of circadian genes, particularly in obese mice. Because some of the 11 drugs can be found in drinking water at such concentrations (e.g. acetaminophen, carbamazepine, ibuprofen) our data could be relevant in environmental toxicology, especially for obese individuals exposed to these contaminants. - Highlights: • The contamination of drinking water with drugs may have harmful effects on health. • Some drugs can be more hepatotoxic in the context of obesity and fatty liver. • Effects of chronic exposure of trace drugs were studied in lean and obese mouse liver. Drugs and obesity present additive effects on circadian gene expression and toxicity. • Trace pharmaceuticals could be harmful for the liver, especially in obese individuals.« less

Short-term effects of T-2 toxin or deoxynivalenol on lipid peroxidation and the glutathione system in common carp.

PubMed

Pelyhe, Csilla; Kövesi, Benjámin; Zándoki, Erika; Kovács, Balázs; Szabó-Fodor, Judit; Mézes, Miklós; Balogh, Krisztián

2016-12-01

The purpose of this study was to investigate the short-term effects of a single oral dose of T-2 and HT-2 toxin at 0.15, 0.33 and 1.82 mg kg -1 body weight, or deoxynivalenol (DON) and 15-acetyl-DON at 0.13, 0.31 and 1.75 mg kg -1 body weight in common carp. Conjugated dienes and trienes (the early markers of lipid peroxidation) were elevated in all DON-treated groups at the 16th hour, while thiobarbituric acid reactive substances (TBARS; termination marker) were increased at the highest dose of DON at the 16th and 24th hours. T-2 toxin did not cause changes in these parameters. Glutathione content and glutathione peroxidase activity showed higher levels at the 16th hour as the effect of both mycotoxins. The expression of glutathione peroxidase (GPx4) genes (gpx4a and gpx4b) revealed a dual response. Downregulation was observed at the 8th hour, followed by an induction at the 16th hour, at the lowest dose of both mycotoxins. Higher doses revealed long-drawn emergence and an elevation was observed only at the 24th hour. However, at the lowest and highest doses of DON or T-2 toxin the changes in gene expression were delayed, which may be related to the low oxidative stress response, as suggested by the expression profiles of the nrf2, keap1, gpx4a and gpx4b genes.

Dose-Response for Multiple Biomarkers of Exposure and Genotoxic Effect Following Repeated Treatment of Rats with the Alkylating Agents, MMS and MNU.

PubMed

Ji, Zhiying; LeBaron, Matthew J; Schisler, Melissa R; Zhang, Fagen; Bartels, Michael J; Gollapudi, B Bhaskar; Pottenger, Lynn H

2016-05-01

The nature of the dose-response relationship for various in vivo endpoints of exposure and effect were investigated using the alkylating agents, methyl methanesulfonate (MMS) and methylnitrosourea (MNU). Six male F344 rats/group were dosed orally with 0, 0.5, 1, 5, 25 or 50mg/kg bw/day (mkd) of MMS, or 0, 0.01, 0.1, 1, 5, 10, 25 or 50 mkd of MNU, for 4 consecutive days and sacrificed 24h after the last dose. The dose-responses for multiple biomarkers of exposure and genotoxic effect were investigated. In MMS-treated rats, the hemoglobin adduct level, a systemic exposure biomarker, increased linearly with dose (r (2) = 0.9990, P < 0.05), indicating the systemic availability of MMS; however, the N7MeG DNA adduct, a target exposure biomarker, exhibited a non-linear dose-response in blood and liver tissues. Blood reticulocyte micronuclei (MN), a genotoxic effect biomarker, exhibited a clear no-observed-genotoxic-effect-level (NOGEL) of 5 mkd as a point of departure (PoD) for MMS. Two separate dose-response models, the Lutz and Lutz model and the stepwise approach using PROC REG both supported a bilinear/threshold dose-response for MN induction. Liver gene expression, a mechanistic endpoint, also exhibited a bilinear dose-response. Similarly, in MNU-treated rats, hepatic DNA adducts, gene expression changes and MN all exhibited clear PoDs, with a NOGEL of 1 mkd for MN induction, although dose-response modeling of the MNU-induced MN data showed a better statistical fit for a linear dose-response. In summary, these results provide in vivo data that support the existence of clear non-linear dose-responses for a number of biologically significant events along the pathway for genotoxicity induced by DNA-reactive agents. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Identification of Differential Gene Expression Patterns after Acute Exposure to High and Low Doses of Low-LET Ionizing Radiation in a Reconstituted Human Skin Tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tilton, Susan C.; Markillie, Lye Meng; Hays, Spencer

Our goal here was to identify dose and temporal dependent radiation responses in a complex tissue, reconstituted human skin. Direct sequencing of RNA (RNA-seq) was used to quantify altered transcripts following exposure to 0.1, 2 and 10 Gy of ionizing radiation at 3 and 8 hours. These doses include a low dose in the range of some medical diagnostic procedures (0.1 Gy), a dose typically received during radiotherapy (2.0 Gy) and a lethal dose (10 Gy). These doses could be received after an intentional or accidental radiation exposure and biomarkers are needed to rapidly and accurately triage exposed individuals. Amore » total of 1701 genes were deemed to be significantly affected by high dose radiation exposure with the majority of genes affected at 10 Gy. A group of 29 genes including GDF15, BBC3, PPM1D, FDXR, GADD45A, MDM2, CDKN1A, TP53INP1, CYCSP27, SESN1, SESN2, PCNA, and AEN were similarly altered at both 2 and 10 Gy, but not 0.1 Gy, at multiple time points. A much larger group of up regulated genes, including those involved in inflammatory responses, was significantly altered only after a 10 Gy exposure. At high doses, down regulated genes were associated with cell cycle regulation and exhibited an apparent linear response between 2 and 10 Gy. While only a handful of genes were significantly affected by 0.1 Gy exposure using stringent statistical filters, groups of related genes regulating cell cycle progression and inflammatory responses consistently exhibited opposite trends in their regulation compared to the high dose exposures. Differential regulation of PLK1 signaling at low and high doses was confirmed using qRT-PCR. These results indicate that some alterations in gene expression are qualitatively different at low and high doses of radiation in this model system.« less

Pharmacogenetic Predictors of Methylphenidate Dose-Response in Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Froehlich, Tanya E.; Epstein, Jeffery N.; Nick, Todd G.; Melguizo Castro, Maria S.; Stein, Mark A.; Brinkman, William B.; Graham, Amanda J.; Langberg, Joshua M.; Kahn, Robert S.

2011-01-01

Objective: Because of significant individual variability in attention-deficit/hyperactivity disorder (ADHD) medication response, there is increasing interest in identifying genetic predictors of treatment effects. This study examined the role of four catecholamine-related candidate genes in moderating methylphenidate (MPH) dose-response. Method:…

Concordance of Transcriptional and Apical Benchmark Dose Levels for Conazole-Induced Liver Effects in Mice

EPA Science Inventory

ABSTRACT The ability to anchor chemical class-based gene expression changes to phenotypic lesions and to describe these changes as a function of dose and time informs mode of action determinations and improves quantitative risk assessments. Previous transcription-based microarra...

Methylphenidate side effect profile is influenced by genetic variation in the attention-deficit/hyperactivity disorder-associated CES1 gene.

PubMed

Johnson, Katherine A; Barry, Edwina; Lambert, David; Fitzgerald, Michael; McNicholas, Fiona; Kirley, Aiveen; Gill, Michael; Bellgrove, Mark A; Hawi, Ziarih

2013-12-01

A naturalistic, prospective study of the influence of genetic variation on dose prescribed, clinical response, and side effects related to stimulant medication in 77 children with attention-deficit/hyperactivity disorder (ADHD) was undertaken. The influence of genetic variation of the CES1 gene coding for carboxylesterase 1A1 (CES1A1), the major enzyme responsible for the first-pass, stereoselective metabolism of methylphenidate, was investigated. Parent- and teacher-rated behavioral questionnaires were collected at baseline when the children were medication naïve, and again at 6 weeks while they were on medication. Medication dose, prescribed at the discretion of the treating clinician, and side effects, were recorded at week 6. Blood and saliva samples were collected for genotyping. Single nucleotide polymorphisms (SNPs) were selected in the coding, non-coding and the 3' flanking region of the CES1 gene. Genetic association between CES1 variants and ADHD was investigated in an expanded sample of 265 Irish ADHD families. Analyses were conducted using analysis of covariance (ANCOVA) and logistic regression models. None of the CES1 gene variants were associated with the dose of methylphenidate provided or the clinical response recorded at the 6 week time point. An association between two CES1 SNP markers and the occurrence of sadness as a side effect of short-acting methylphenidate was found. The two associated CES1 markers were in linkage disequilibrium and were significantly associated with ADHD in a larger sample of ADHD trios. The associated CES1 markers were also in linkage disequilibrium with two SNP markers of the noradrenaline transporter gene (SLC6A2). This study found an association between two CES1 SNP markers and the occurrence of sadness as a side effect of short-acting methylphenidate. These markers were in linkage disequilibrium together and with two SNP markers of the noradrenaline transporter gene.

Psychopharmacology of theobromine in healthy volunteers.

PubMed

Baggott, Matthew J; Childs, Emma; Hart, Amy B; de Bruin, Eveline; Palmer, Abraham A; Wilkinson, Joy E; de Wit, Harriet

2013-07-01

Theobromine, a methylxanthine related to caffeine and present in high levels in cocoa, may contribute to the appeal of chocolate. However, current evidence for this is limited. We conducted a within-subjects placebo-controlled study of a wide range of oral theobromine doses (250, 500, and 1,000 mg) using an active control dose of caffeine (200 mg) in 80 healthy participants. Caffeine had the expected effects on mood including feelings of alertness and cardiovascular parameters. Theobromine responses differed according to dose; it showed limited subjective effects at 250 mg and negative mood effects at higher doses. It also dose-dependently increased heart rate. In secondary analyses, we also examined individual differences in the drug's effects in relation to genes related to their target receptors, but few associations were detected. This study represents the highest dose of theobromine studied in humans. We conclude that theobromine at normal intake ranges may contribute to the positive effects of chocolate, but at higher intakes, effects become negative.

Psychopharmacology of theobromine in healthy volunteers

PubMed Central

Baggott, Matthew J.; Childs, Emma; Hart, Amy B.; de Bruin, Eveline; Palmer, Abraham A.; Wilkinson, Joy E.; de Wit, Harriet

2013-01-01

Background Theobromine, a methylxanthine related to caffeine and present in high levels in cocoa, may contribute to the appeal of chocolate. However, currently evidence for this is limited. Objectives We conducted a within-subjects placebo-controlled study of a wide range of oral theobromine doses (250, 500, and 1000 mg) using an active control dose of caffeine (200 mg) in 80 healthy participants. Results Caffeine had the expected effects on mood including feelings of alertness, and cardiovascular parameters. Theobromine responses differed according to dose: it showed limited subjective effects at 250 mg and negative mood effects at higher doses. It also dose-dependently increased heart rate. In secondary analyses we also examined individual differences in the drugs' effects in relation to genes related to their target receptors, but few associations were detected. Conclusions This study represents the highest dose of theobromine studied in humans. We conclude that theobromine at normal intake ranges may contribute to the positive effects of chocolate, but at higher intakes effects become negative. PMID:23420115

Early Life Exposure to Endocrine-Disrupting Chemicals Causes Lifelong Molecular Reprogramming of the Hypothalamus and Premature Reproductive Aging

PubMed Central

Walker, Deena M.; Zama, Aparna M.; Armenti, AnnMarie E.; Uzumcu, Mehmet

2011-01-01

Gestational exposure to the estrogenic endocrine disruptor methoxychlor (MXC) disrupts the female reproductive system at the molecular, physiological, and behavioral levels in adulthood. The current study addressed whether perinatal exposure to endocrine disruptors reprograms expression of a suite of genes expressed in the hypothalamus that control reproductive function and related these molecular changes to premature reproductive aging. Fischer rats were exposed daily for 12 consecutive days to vehicle (dimethylsulfoxide), estradiol benzoate (EB) (1 mg/kg), and MXC (low dose, 20 μg/kg or high dose, 100 mg/kg), beginning on embryonic d 19 through postnatal d 7. The perinatally exposed females were aged to 16–17 months and monitored for reproductive senescence. After euthanasia, hypothalamic regions [preoptic area (POA) and medial basal hypothalamus] were dissected for real-time PCR of gene expression or pyrosequencing to assess DNA methylation of the Esr1 gene. Using a 48-gene PCR platform, two genes (Kiss1 and Esr1) were significantly different in the POA of endocrine-disrupting chemical-exposed rats compared with vehicle-exposed rats after Bonferroni correction. Fifteen POA genes were up-regulated by at least 50% in EB or high-dose MXC compared with vehicle. To understand the epigenetic basis of the increased Esr1 gene expression, we performed bisulfite conversion and pyrosequencing of the Esr1 promoter. EB-treated rats had significantly higher percentage of methylation at three CpG sites in the Esr1 promoter compared with control rats. Together with these molecular effects, perinatal MXC and EB altered estrous cyclicity and advanced reproductive senescence. Thus, early life exposure to endocrine disruptors has lifelong effects on neuroendocrine gene expression and DNA methylation, together with causing the advancement of reproductive senescence. PMID:22016562

Micro RNA responses to chronic or acute exposures to low dose ionizing radiation

PubMed Central

Chaudhry, M. Ahmad; Omaruddin, Romaica A.; Kreger, Bridget; de Toledo, Sonia M.; Azzam, Edouard I.

2014-01-01

Human health risks of exposure to low dose ionizing radiation remain ambiguous and are the subject of intense debate. A wide variety of biological effects are induced after cellular exposure to ionizing radiation, but the underlying molecular mechanism(s) remain to be completely understood. We hypothesized that low dose c-radiation-induced effects are controlled by the modulation of micro RNA (miRNA) that participate in the control of gene expression at the posttranscriptional level and are involved in many cellular processes. We monitored the expression of several miRNA in human cells exposed to acute or chronic low doses of 10 cGy or a moderate dose of 400 cGy of 137Cs γ-rays. Dose, dose rate and time dependent differences in the relative expression of several miRNA were investigated. The expression patterns of many miRNA differed after exposure to either chronic or acute 10 cGy. The expression of miRNA let-7e, a negative regulator of RAS oncogene, and the c-MYC miRNA cluster were upregulated after 10 cGy chronic dose but were downregulated after 3 h of acute 10 cGy. The miR-21 was upregulated in chronic or acute low dose and moderate dose treated cells and its target genes hPDCD4, hPTEN, hSPRY2, and hTPM1 were found to be downregulated. These findings provide evidence that low dose and dose rate c-irradiation dictate the modulation of miRNA, which can result in a differential cellular response than occurs at high doses. This information will contribute to understanding the risks to human health after exposure to low dose radiation. PMID:22367372

Long-Term Effect of Gene Therapy on Leber’s Congenital Amaurosis

PubMed Central

Bainbridge, J.W.B.; Mehat, M.S.; Sundaram, V.; Robbie, S.J.; Barker, S.E.; Ripamonti, C.; Georgiadis, A.; Mowat, F.M.; Beattie, S.G.; Gardner, P.J.; Feathers, K.L.; Luong, V.A.; Yzer, S.; Balaggan, K.; Viswanathan, A.; de Ravel, T.J.L.; Casteels, I.; Holder, G.E.; Tyler, N.; Fitzke, F.W.; Weleber, R.G.; Nardini, M.; Moore, A.T.; Thompson, D.A.; Petersen-Jones, S.M.; Michaelides, M.; van den Born, L.I.; Stockman, A.; Smith, A.J.; Rubin, G.; Ali, R.R.

2015-01-01

BACKGROUND Mutations in RPE65 cause Leber’s congenital amaurosis, a progressive retinal degenerative disease that severely impairs sight in children. Gene therapy can result in modest improvements in night vision, but knowledge of its efficacy in humans is limited. METHODS We performed a phase 1–2 open-label trial involving 12 participants to evaluate the safety and efficacy of gene therapy with a recombinant adeno-associated virus 2/2 (rAAV2/2) vector carrying the RPE65 complementary DNA, and measured visual function over the course of 3 years. Four participants were administered a lower dose of the vector, and 8 were administered a higher dose. In a parallel study in dogs, we investigated the relationship among vector dose, visual function, and electroretinography (ERG) findings. RESULTS Improvements in retinal sensitivity were evident, to varying extents, in six participants for up to 3 years, peaking at 6 to 12 months after treatment and then declining. No associated improvement in retinal function was detected by means of ERG. Three participants had intraocular inflammation, and two had clinically significant deterioration of visual acuity. The reduction in central retinal thickness varied among participants. In dogs, RPE65 gene therapy with the same vector at lower doses improved vision-guided behavior, but only higher doses resulted in improvements in retinal function that were detectable with the use of ERG. CONCLUSIONS Gene therapy with rAAV2/2 RPE65 vector improved retinal sensitivity, albeit modestly and temporarily. Comparison with the results obtained in the dog model indicates that there is a species difference in the amount of RPE65 required to drive the visual cycle and that the demand for RPE65 in affected persons was not met to the extent required for a durable, robust effect. (Funded by the National Institute for Health Research and others; ClinicalTrials.gov number, NCT00643747.) PMID:25938638

Transcriptome analysis of reproductive-stage Arabidopsis plants exposed gamma-ray irradiation at various doses.

PubMed

Hwang, Sun-Goo; Kim, Dong Sub; Kim, Jin-Baek; Hwang, Jung Eun; Park, Hyun Mi; Kim, Jin Hyuk; Jang, Cheol Seong

2016-08-01

Gamma rays (GR) induce significant changes in the structure and expression of genes involved in the regulation of diverse biochemical and physiological processes. Arabidopsis plants exhibit different growth and development patterns in response to exposure to GR. The effects on gene expression of different radiation doses of GR (100 and 800 Gy) administered to Arabidopsis plants were examined at the reproductive stage. We irradiated 26-day-old plants with three replications [developmental stages 5.1-6.0, according to Boyes et al. ( 2001 )] using a GR irradiator (60 Co, ca. 150 TBq capacity, Atomic Energy of Canada Limited, Ontario, Canada) at the Korea Atomic Energy Research Institute. Plants were treated with 100, 200, 300, 400, 800, 1200, 1600, or 2000 Gy, and the doses were made from varying the distance to the source. We conducted a high-throughput screening analysis and detected 883 GR-responsive genes that showed significant changes; these were involved in several putative metabolic pathways related to biotic stress. Additionally, five overrepresented cis-regulatory elements were identified in the 1-kb upstream regions of GR-responsive genes by using motif enrichment analysis. We also detected three GR-responsive genes associated with stamen development and confirmed their co-regulation with functionally interacting genes. This finding suggests that a network-based analysis is a viable approach to identify significant GR-responsive genes associated with the reproductive stage of Arabidopsis. Our results provide further insights into the complex biological systems involved in the response to different doses of GR in plants.

Bovine spongiform encephalopathy: the effect of oral exposure dose on attack rate and incubation period in cattle - an update.

PubMed

Konold, Timm; Arnold, Mark E; Austin, Anthony R; Cawthraw, Saira; Hawkins, Steve A C; Stack, Michael J; Simmons, Marion M; Sayers, A Robin; Dawson, Michael; Wilesmith, John W; Wells, Gerald A H

2012-12-05

To provide information on dose-response and aid in modelling the exposure dynamics of the BSE epidemic in the United Kingdom groups of cattle were exposed orally to a range of different doses of brainstem homogenate of known infectious titre from clinical cases of classical bovine spongiform encephalopathy (BSE). Interim data from this study was published in 2007. This communication documents additional BSE cases, which occurred subsequently, examines possible influence of the bovine prion protein gene on disease incidence and revises estimates of effective oral exposure. Following interim published results, two further cattle, one dosed with 100 mg and culled at 127 months post exposure and the other dosed with 10 mg and culled at 110 months post exposure, developed BSE. Both had a similar pathological phenotype to previous cases. Based on attack rate and incubation period distribution according to dose, the dose estimate at which 50% of confirmed cases would be clinically affected was revised to 0.15 g of the brain homogenate used in the experiment, with a 95% confidence interval of 0.03-0.79 g. Neither the full open reading frame nor the promoter region of the prion protein gene of dosed cattle appeared to influence susceptibility to BSE, but this may be due to the sample size. Oral exposure of cattle to a large range of doses of a BSE brainstem homogenate produced disease in all dose groups. The pathological presentation resembled natural disease. The attack rate and incubation period were dependent on the dose.

Dose-dependent effects on sphingoid bases and cytokines in chickens fed diets prepared with fusarium verticillioides culture material containing fumonisins.

PubMed

Grenier, Bertrand; Schwartz-Zimmermann, Heidi E; Caha, Sylvia; Moll, Wulf Dieter; Schatzmayr, Gerd; Applegate, Todd J

2015-04-13

In chickens, the effect of mycotoxins, especially fumonisins (FB), in the gastrointestinal tract (GIT) is not well documented. Thus, this study in broiler chicks determined the effects of consuming diets prepared with Fusarium verticillioides culture material containing FB on intestinal gene expression and on the sphinganine (Sa)/sphingosine (So) ratio (Sa/So; a biomarker of FB effect due to disruption of sphingolipid metabolism). Male broilers were assigned to 6 diets (6 cages/diet; 6 birds/cage) from hatch to 20 days containing 0.4, 5.6, 11.3, 17.5, 47.8, or 104.8 mg FB/kg diet. Exposure to FB altered the Sa/So ratio in all tissues analyzed, albeit to varying extents. Linear dose-responses were observed in the kidney, jejunum and cecum. The liver and the ileum were very sensitive and data fit a cubic and quadratic polynomial model, respectively. Gene expression in the small intestine revealed low but significant upregulations of cytokines involved in the pro-inflammatory, Th1/Th17 and Treg responses, especially at 10 days of age. Interestingly, the cecal tonsils exhibited a biphasic response. Unlike the sphingolipid analysis, the effects seen on gene expression were not dose dependent, even showing more effects when birds were exposed to 11.3 mg FB/kg. In conclusion, this is the first report on the disruption of the sphingolipid metabolism by FB in the GIT of poultry. Further studies are needed to reach conclusions on the biological meaning of the immunomodulation observed in the GIT, but the susceptibility of chickens to intestinal pathogens when exposed to FB, at doses lower than those that would cause overt clinical symptoms, should be addressed.

Dose- and Ion-Dependent Effects in the Oxidative Stress Response to Space-Like Radiation Exposure in the Skeletal System

NASA Technical Reports Server (NTRS)

Alwood, Joshua S.; Tran, Luan H.; Schreurs, Ann-Sofie; Shirazi-Fard, Yasaman; Kumar, Akhilesh; Hilton, Diane; Tahimic, Candice G. T.; Globus, Ruth

2017-01-01

Exposure to space radiation may pose a risk to skeletal health during subsequent aging. Irradiation acutely stimulates bone remodeling in mice, although the long-term influence of space radiation on bone-forming potential (osteoblastogenesis) and possible adaptive mechanisms are not well understood. We hypothesized exposure to ionizing radiation impairs osteoblastogenesis in an ion-type specific manner, with low doses capable of modulating expression of redox-related genes. 16-week old, male, C57BL6/J mice were exposed to low linear-energy-transfer (LET) protons (150 mega electron volts per nucleon) or high-LET (sup 56) Fe ions (600 mega electron volts per nucleon) using either low (5 or 10 centigrays) or high (50 or 200 centigrays) doses at NASAs Space Radiation Lab at Brookhaven National Lab (NSRL/BNL). Tissues were harvested 5 weeks or 1 year after irradiation and bones were analyzed by microcomputed tomography for cancellous microarchitecture and cortical geometry. Marrow-derived, adherent cells were grown under osteoblastogenic culture conditions. Cell lysates were analyzed for select groups by RT-PCR (Reverse Transcription-Polymerase Chain Reaction) during the proliferative phase or the mineralizing phase, and differentiation was analyzed by imaging mineralized nodules (percentage surface area). Representative genes were selected for expression analyses, including cell proliferation (PCNA, Cdk2, p21, p53), differentiation (Runx2, Alpl, Bglap), oxidative metabolism (Catalase, GPX, MnSOD, CuZnSOD, iNos, Foxo1), DNA-damage repair (Gadd45), or apoptosis (Caspase 3). As expected, a high dose (200 centigrays), but not low doses, of either (sup 56) Fe or protons caused a loss of cancellous bone volume per total volume. Marrow cells produced mineralized nodules ex vivo regardless of radiation type or dose; (sup 56) Fe (200 centigrays) inhibited median nodule area by more than 90 percent at 5 weeks and 1 year post-irradiation, compared to controls. At 5 weeks post exposure, irradiation with protons or (sup 56) Fe caused few changes in gene expression levels during osteoblastogenesis, although a high dose of (sup 56) Fe (200 centigrays) increased levels of Catalase and Gadd45. In addition, supplementing cell culture media with SOD protected marrow-derived osteoprogenitors from the damaging effects of exposure to low-LET ((sup 137) Cs gamma) if irradiated in vitro, but had limited protective effects on high-LET (sup 56) Fe-exposed cells. In sum, exposure of mice to either protons or (sup 56) Fe at a relatively high dose (200 cGy) caused persistent bone loss, whereas only high-LET (sup 56) Fe increased expression of redox-related genes and inhibited osteoblastogenesis, albeit to a limited extent. We conclude that high-LET irradiation impaired osteoblastogenesis and regulated steady-state gene expression of select redox-related genes during osteoblastogenesis, which may contribute to persistent bone loss.

Determining Cutoff Point of Ensemble Trees Based on Sample Size in Predicting Clinical Dose with DNA Microarray Data.

PubMed

Yılmaz Isıkhan, Selen; Karabulut, Erdem; Alpar, Celal Reha

2016-01-01

Background/Aim . Evaluating the success of dose prediction based on genetic or clinical data has substantially advanced recently. The aim of this study is to predict various clinical dose values from DNA gene expression datasets using data mining techniques. Materials and Methods . Eleven real gene expression datasets containing dose values were included. First, important genes for dose prediction were selected using iterative sure independence screening. Then, the performances of regression trees (RTs), support vector regression (SVR), RT bagging, SVR bagging, and RT boosting were examined. Results . The results demonstrated that a regression-based feature selection method substantially reduced the number of irrelevant genes from raw datasets. Overall, the best prediction performance in nine of 11 datasets was achieved using SVR; the second most accurate performance was provided using a gradient-boosting machine (GBM). Conclusion . Analysis of various dose values based on microarray gene expression data identified common genes found in our study and the referenced studies. According to our findings, SVR and GBM can be good predictors of dose-gene datasets. Another result of the study was to identify the sample size of n = 25 as a cutoff point for RT bagging to outperform a single RT.

Tritiated water exposure disrupts myofibril structure and induces mis-regulation of eye opacity and DNA repair genes in zebrafish early life stages.

PubMed

Arcanjo, Caroline; Armant, Olivier; Floriani, Magali; Cavalie, Isabelle; Camilleri, Virginie; Simon, Olivier; Orjollet, Daniel; Adam-Guillermin, Christelle; Gagnaire, Béatrice

2018-04-27

Tritium ( 3 H) is a radioactive isotope of hydrogen. In the environment, the most common form of tritium is tritiated water (HTO). The present study aimed to identify early biomarkers of HTO contamination through the use of an aquatic model, the zebrafish (Danio rerio). We used the zebrafish embryo-larvae model to investigate the modes of action of HTO exposure at dose rates of 0.4 and 4 mGy/h, dose rates expected to induce deleterious effects on fish. Zebrafish were exposed to HTO from 3 hpf (hours post fertilization) to 96 hpf. The transcriptomic effects were investigated 24 h and 96 h after the beginning of the contamination, using mRNAseq. Results suggested an impact of HTO contamination, regardless of the dose rate, on genes involved in muscle contraction (tnnt2d, tnni2a.4, slc6a1a or atp2a1l) and eye opacity (crygm2d9, crygmxl1, mipb or lim2.3) after 24 h of contamination. Interestingly, an opposite differential expression was highlighted in genes playing a role in muscle contraction and eye opacity in 24 hpf embryos when comparing dose rates, suggesting an onset of DNA protective mechanisms. The expression of h2afx and ddb2 involved in DNA repair was enhanced in response to HTO exposure. The entrainment of circadian clock and the response to H 2 O 2 signalling pathways were enriched at 96 hpf at 0.4 mGy/h and in both stages after 4 mGy/h. Genes involved in ROS scavenging were differentially expressed only after 24 h of exposure for the lowest dose rate, suggesting the onset of early protective mechanisms against oxidative stress. Effects highlighted on muscle at the molecular scale were confirmed at a higher biological scale, as electron microscopy observations revealed sarcomere impairments in 96 hpf larvae for both dose rates. Together with other studies, the present work provides useful data to better understand modes of action of tritium on zebrafish embryos-larvae. Copyright © 2018 Elsevier B.V. All rights reserved.

Dose-response relationships in gene expression profiles in rainbow trout, Oncorhyncus mykiss, exposed to ethynylestradiol.

PubMed

Hook, Sharon E; Skillman, Ann D; Small, Jack A; Schultz, Irvin R

2006-07-01

Determining how gene expression profiles change with toxicant dose will improve the utility of arrays in identifying biomarkers and modes of toxic action. Isogenic rainbow trout, Oncorhyncus mykiss,were exposed to 10, 50 or 100 ng/L ethynylestradiol (a xeno-estrogen) for 7 days. Following exposure hepatic RNA was extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNAs. Transcript expression in treated vs control fish was analyzed via Genespring (Silicon Genetics) to identify genes with altered expression, as well as to determine gene clustering patterns that can be used as "expression signatures". Array results were confirmed via qRT PCR. Our analysis indicates that gene expression profiles varied somewhat with dose. Established biomarkers of exposure to estrogenic chemicals, such as vitellogenin, vitelline envelope proteins, and the estrogen receptor alpha, were induced at every dose. Other genes were dose specific, suggesting that different doses induce distinct physiological responses. These findings demonstrate that cDNA microarrays could be used to identify both toxicant class and relative dose.

Estrogen receptors and biologic response in rat parathyroid tissue and C cells.

PubMed Central

Naveh-Many, T; Almogi, G; Livni, N; Silver, J

1992-01-01

The expression of the PTH and calcitonin genes is dramatically decreased by 1,25(OH)2D3 in vivo, and the PTH gene expression is increased by hypocalcemia. We have now studied the effect of estrogens on the expression of these genes in vivo. 17 beta-Estradiol, given to ovariectomized rats, led to a fourfold increase in PTH mRNA and calcitonin mRNA levels. These effects occurred 24 h after single injections of 37-145 nmol estradiol, or after constant infusions of 12 pmol/d for 1 or 2 wk, where there was no effect on serum calcium levels. The estrogen receptor mRNA was demonstrated in the thyroparathyroid tissue by polymerase chain reaction. The estrogen binding was localized to the parathyroid and C cells by immunohistochemistry. Uterus weight was increased by repeated larger doses (73 nmol/d x 7) of estradiol, but not by the small doses (12 pmol/d for 1 or 2 wk) which were effective on the PTH and calcitonin genes, suggesting a sensitive endocrine effect. These results confirm that the parathyroid and C cells are target organs for estrogen, leading to an increased expression of PTH and calcitonin, which by their combined anabolic effect on bone would help prevent osteoporosis. Images PMID:1469095

Expression of Genes Associated with DNA Damage Sensing in Human Fibroblasts Exposed to Low-dose-rate Gamma Rays

NASA Technical Reports Server (NTRS)

Zhang, Ye; Mehta, Satish; Hammond, Diane; Pierson, Duane; Jeevarajan, Antony; Cucinotta, Francis; Rohde, Larry; Wu, Honglu

2007-01-01

Understanding of the molecular response to low-dose and low-dose-rate radiation exposure is essential for the extrapolation of high-dose radiation risks to those at dose levels relevant to space and other environmental concerns. Most of the reported studies of gene expressions induced by low-dose or low-dose-rate radiation were carried out on exponentially growing cells. In the present study, we analyzed expressions of 84 genes associated with DNA damage sensing using real time PCR in human fibroblasts in mostly G1 phase of the cell cycle. The cells were exposed continuously to gamma rays at a dose rate of 0.8 cGy/hr for 1, 2, 6 or 24 hrs at 37 C throughout the exposure. The total RNA was isolated immediately after the exposure was terminated. Of the 84 genes, only a few showed significant changes of the expression level. Some of the genes (e.g. DDit3 and BTG2) were found to be up or down regulated only after a short period of exposure, while other genes (e.g. PRKDC) displayed a highest expression level at the 24 hr time point. The expression profiles for the exposed cells which had a smaller portion of G1 cells indicated more cell cycle signaling and DNA repair genes either up or down regulated. Interestingly, the panel of genes changed from radiation exposure in G1 cells is different from the panel in cells having less G1 arrest cells. The gene expression profile of the cells responding to low-dose-radiation insult apparently depends on the cell growth stage. The response pathway in G1 cells may differ from that in exponentially growing cells.

Profound and Sexually Dimorphic Effects of Clinically-Relevant Low Dose Scatter Irradiation on the Brain and Behavior

PubMed Central

Kovalchuk, Anna; Mychasiuk, Richelle; Muhammad, Arif; Hossain, Shakhawat; Ilnytskyy, Yaroslav; Ghose, Abhijit; Kirkby, Charles; Ghasroddashti, Esmaeel; Kolb, Bryan; Kovalchuk, Olga

2016-01-01

Irradiated cells can signal damage and distress to both close and distant neighbors that have not been directly exposed to the radiation (naïve bystanders). While studies have shown that such bystander effects occur in the shielded brain of animals upon body irradiation, their mechanism remains unexplored. Observed effects may be caused by some blood-borne factors; however they may also be explained, at least in part, by very small direct doses received by the brain that result from scatter or leakage. In order to establish the roles of low doses of scatter irradiation in the brain response, we developed a new model for scatter irradiation analysis whereby one rat was irradiated directly at the liver and the second rat was placed adjacent to the first and received a scatter dose to its body and brain. This work focuses specifically on the response of the latter rat brain to the low scatter irradiation dose. Here, we provide the first experimental evidence that very low, clinically relevant doses of scatter irradiation alter gene expression, induce changes in dendritic morphology, and lead to behavioral deficits in exposed animals. The results showed that exposure to radiation doses as low as 0.115 cGy caused changes in gene expression and reduced spine density, dendritic complexity, and dendritic length in the prefrontal cortex tissues of females, but not males. In the hippocampus, radiation altered neuroanatomical organization in males, but not in females. Moreover, low dose radiation caused behavioral deficits in the exposed animals. This is the first study to show that low dose scatter irradiation influences the brain and behavior in a sex-specific way. PMID:27375442

Genome-wide gene expression effects in B6C3F1 mouse intestinal epithelia following 7 and 90 days of exposure to hexavalent chromium in drinking water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kopec, Anna K.; Kim, Suntae; Forgacs, Agnes L.

2012-02-15

Chronic administration of high doses of hexavalent chromium [Cr(VI)] as sodium dichromate dihydrate (SDD) elicits alimentary cancers in mice. To further elucidate key events underlying tumor formation, a 90-day drinking water study was conducted in B6C3F1 mice. Differential gene expression was examined in duodenal and jejunal epithelial samples following 7 or 90 days of exposure to 0, 0.3, 4, 14, 60, 170 or 520 mg/L SDD in drinking water. Genome-wide microarray analyses identified 6562 duodenal and 4448 jejunal unique differentially expressed genes at day 8, and 4630 and 4845 unique changes, respectively, in the duodenum and jejunum at day 91.more » Comparative analysis identified significant overlap in duodenal and jejunal differential gene expression. Automated dose–response modeling identified > 80% of the differentially expressed genes exhibited sigmoidal dose–response curves with EC{sub 50} values ranging from 10 to 100 mg/L SDD. Only 16 genes satisfying the dose-dependent differential expression criteria had EC{sub 50} values < 10 mg/L SDD, 3 of which were regulated by Nrf2, suggesting oxidative stress in response to SDD at low concentrations. Analyses of differentially expressed genes identified over-represented functions associated with oxidative stress, cell cycle, lipid metabolism, and immune responses consistent with the reported effects on redox status and histopathology at corresponding SDD drinking water concentrations. Collectively, these data are consistent with a mode of action involving oxidative stress and cytotoxicity as early key events. This suggests that the tumorigenic effects of chronic Cr(VI) oral exposure likely require chronic tissue damage and compensatory epithelial cell proliferation. Highlights: ► Mouse small intestine gene expression is highly responsive to hexavalent chromium [Cr(VI)]. ► Cr(VI) elicits more differential gene expression after 7 days of exposure than 90 days of exposure. ► Oral exposure to Cr(VI) leads to oxidative stress, cell cycle, lipid and immune dysregulation. ► Cr(VI) elicits dose-dependent changes in gene expression with an overall median EC{sub 50} of 47 mg/L SDD.« less

DEVELOPMENTAL NEUROTOXICITY OF ORGANOPHOSPHATES TARGETS CELL CYCLE AND APOPTOSIS, REVEALED BY TRANSCRIPTIONAL PROFILES IN VIVO AND IN VITRO

PubMed Central

Slotkin, Theodore A.; Seidler, Frederic J.

2012-01-01

Developmental organophosphate exposure reduces the numbers of neural cells, contributing to neurobehavioral deficits. We administered chlorpyrifos or diazinon to newborn rats on postnatal days 1–4, in doses straddling the threshold for barely-detectable cholinesterase, and evaluated gene expression in the cell cycle and apoptosis pathways on postnatal day 5. Both organophosphates evoked transcriptional changes in 20–25% of the genes in each category; chlorpyrifos and diazinon targeted the same genes, with similar magnitudes of change, as evidenced by high concordance. Furthermore, the same effects were obtained with doses above or below the threshold for cholinesterase inhibition, indicating a mechanism unrelated to anticholinesterase actions. We then evaluated the effects of chlorpyrifos in undifferentiated and differentiating PC12 cells and found even greater targeting of cell cycle and apoptosis genes, affecting up to 40% of all genes in the pathways. Notably, the genes affected in undifferentiated cells were not concordant with those in differentiating cells, pointing to dissimilar outcomes dependent on developmental stage. The in vitro model successfully identified 60–70% of the genes affected by chlorpyrifos in vivo, indicating that the effects are exerted directly on developing neural cells. Our results show that organophosphates target the genes regulating the cell cycle and apoptosis in the developing brain and in neuronotypic cells in culture, with the pattern of vulnerability dependent on the specific stage of development. Equally important, these effects do not reflect actions on cholinesterase and operate at exposures below the threshold for any detectable inhibition of this enzyme. PMID:22222554

Developmental neurotoxicity of organophosphates targets cell cycle and apoptosis, revealed by transcriptional profiles in vivo and in vitro.

PubMed

Slotkin, Theodore A; Seidler, Frederic J

2012-03-01

Developmental organophosphate exposure reduces the numbers of neural cells, contributing to neurobehavioral deficits. We administered chlorpyrifos or diazinon to newborn rats on postnatal days 1-4, in doses straddling the threshold for barely-detectable cholinesterase inhibition, and evaluated gene expression in the cell cycle and apoptosis pathways on postnatal day 5. Both organophosphates evoked transcriptional changes in 20-25% of the genes in each category; chlorpyrifos and diazinon targeted the same genes, with similar magnitudes of change, as evidenced by high concordance. Furthermore, the same effects were obtained with doses above or below the threshold for cholinesterase inhibition, indicating a mechanism unrelated to anticholinesterase actions. We then evaluated the effects of chlorpyrifos in undifferentiated and differentiating PC12 cells and found even greater targeting of cell cycle and apoptosis genes, affecting up to 40% of all genes in the pathways. Notably, the genes affected in undifferentiated cells were not concordant with those in differentiating cells, pointing to dissimilar outcomes dependent on developmental stage. The in vitro model successfully identified 60-70% of the genes affected by chlorpyrifos in vivo, indicating that the effects are exerted directly on developing neural cells. Our results show that organophosphates target the genes regulating the cell cycle and apoptosis in the developing brain and in neuronotypic cells in culture, with the pattern of vulnerability dependent on the specific stage of development. Equally important, these effects do not reflect actions on cholinesterase and operate at exposures below the threshold for any detectable inhibition of this enzyme. Copyright © 2011 Elsevier Inc. All rights reserved.

Corn rootworm-active RNA DvSnf7: Repeat dose oral toxicology assessment in support of human and mammalian safety.

PubMed

Petrick, Jay S; Frierdich, Gregory E; Carleton, Stephanie M; Kessenich, Colton R; Silvanovich, Andre; Zhang, Yuanji; Koch, Michael S

2016-11-01

Genetically modified (GM) crops have been developed and commercialized that utilize double stranded RNAs (dsRNA) to suppress a target gene(s), producing virus resistance, nutritional and quality traits. MON 87411 is a GM maize variety that leverages dsRNAs to selectively control corn rootworm through production of a 240 base pair (bp) dsRNA fragment targeting for suppression the western corn rootworm (Diabrotica virgifera virgifera) Snf7 gene (DvSnf7). A bioinformatics assessment found that endogenous corn small RNAs matched ∼450 to 2300 unique RNA transcripts that likely code for proteins in rat, mouse, and human, demonstrating safe dsRNA consumption by mammals. Mice were administered DvSnf7 RNA (968 nucleotides, including the 240 bp DvSnf7 dsRNA) at 1, 10, or 100 mg/kg by oral gavage in a 28-day repeat dose toxicity study. No treatment-related effects were observed in body weights, food consumption, clinical observations, clinical chemistry, hematology, gross pathology, or histopathology endpoints. Therefore, the No Observed Adverse Effect Level (NOAEL) for DvSnf7 RNA was 100 mg/kg, the highest dose tested. These results demonstrate that dsRNA for insect control does not produce adverse health effects in mammals at oral doses millions to billions of times higher than anticipated human exposures and therefore poses negligible risk to mammals. Copyright © 2016 Monsanto Company. Published by Elsevier Inc. All rights reserved.

Changes in the Peripheral Blood Gene Expression Profile Induced by 3 Months of Valproate Treatment in Patients with Newly Diagnosed Epilepsy

PubMed Central

Rakitin, Aleksei; Kõks, Sulev; Reimann, Ene; Prans, Ele; Haldre, Sulev

2015-01-01

Valproic acid (VPA) is a widely used antiepileptic drug with a broad range of effects and broad clinical efficacy. As a well-known histone deacetylase (HDAC) inhibitor, VPA regulates epigenetic programming by altering the expression of many genes. The aim of study was to analyze differences in gene expression profiles before and after the start of VPA treatment in patients with newly diagnosed epilepsy. RNA sequencing was used to compare whole-genome gene expression patterns of peripheral blood from nine patients with epilepsy before and 3 months after the start of treatment with VPA. Of the 23,099 analyzed genes, only 11 showed statistically significant differential expression with false discovery rate-adjusted p-values below 0.1. Functional annotation and network analyses showed activation of only one genetic network (enrichment score = 30), which included genes for cardiovascular system development and function, cell morphology, and hematological system development and function. The finding of such a small number of differently expressed genes between before and after the start of treatment suggests a lack of HDAC inhibition in these patients, which could be explained by the relatively low doses of VPA that were used. In conclusion, VPA at standard therapeutic dosages modulates the expression of a small number of genes. Therefore, to minimize the potential side effects of HDAC inhibition, it is recommended that the lowest effective dose of VPA be used for treating epilepsy. PMID:26379622

Juvenile Male Rats Exposed to a Low-Dose Mixture of Twenty-Seven Environmental Chemicals Display Adverse Health Effects

PubMed Central

Svingen, Terje; Mandrup, Karen; Skov, Kasper; Pedersen, Mikael; Frederiksen, Hanne; Frandsen, Henrik Lauritz; Vinggaard, Anne Marie

2016-01-01

Humans are exposed to a large number of environmental chemicals in their daily life, many of which are readily detectable in blood or urine. It remains uncertain if these chemicals can cause adverse health effects when present together at low doses. In this study we have tested whether a mixture of 27 chemicals administered orally to juvenile male rats for three months could leave a pathophysiological footprint. The mixture contained metals, perfluorinated compounds, PCB, dioxins, pesticides, heterocyclic amines, phthalate, PAHs and others, with a combined dose of 0.16 (Low dose), 0.47 (Mid dose) or 1.6 (High dose) mg/kg bw/day. The lowest dose was designed with the aim of obtaining plasma or urine concentrations in rats at levels approaching those observed in humans. Some single congeners were administered at doses representative of combined doses for chemical groups. With this baseline, we found effects on weight, histology and gene expression in the liver, as well as changes to the blood plasma metabolome in all exposure groups, including low-dose. Additional adverse effects were observed in the higher dosed groups, including enlarged kidneys and alterations to the metabolome. No significant effects on reproductive parameters were observed. PMID:27598887

Effects of TCDD on the Expression of Nuclear Encoded Mitochondrial Genes

PubMed Central

Forgacs, Agnes L.; Burgoon, Lyle D.; Lynn, Scott G.; LaPres, John J.; Zacharewski, Timothy

2014-01-01

Generation of mitochondrial reactive oxygen species (ROS) can be perturbed following exposure to environmental chemicals such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Reports indicate that the aryl hydrocarbon receptor (AhR) mediates TCDD-induced sustained hepatic oxidative stress by decreasing hepatic ATP levels and through hyperpolarization of the inner mitochondrial membrane. To further elucidate the effects of TCDD on the mitochondria, high-throughput quantitative real-time PCR (HTP-QRTPCR) was used to evaluate the expression of 90 genes encoding mitochondrial proteins involved in electron transport, oxidative phosphorylation, uncoupling, and associated chaperones. HTP-QRTPCR analysis of time course (30 μg/kg TCDD at 2, 4, 8, 12, 18, 24, 72, and 168 hrs) liver samples obtained from orally gavaged immature, ovariectomized C57BL/6 mice identified 54 differentially expressed genes (|fold change|>1.5 and P-value <0.1). Of these, 8 exhibited a dose response (0.03 to 300 μg/kg TCDD) at 4, 24 or 72 hrs. Dose responsive genes encoded proteins associated with electron transport chain (ETC) complex I (NADH dehydrogenase), III (cytochrome c reductase), IV (cytochrome c oxidase), and V (ATP synthase) and could be generally categorized as having proton gradient, ATP synthesis, and chaperone activities. In contrast, transcript levels of ETC complex II, succinate dehydrogenase, remained unchanged. Putative dioxin response elements were computationally found in the promoter regions of the 8 dose-responsive genes. This high-throughput approach suggests that TCDD alters the expression of genes associated with mitochondrial function which may contribute to TCDD-elicited mitochondrial toxicity. PMID:20399798

Ultraviolet B radiation induces impaired lifecycle traits and modulates expression of cytochrome P450 (CYP) genes in the copepod Tigriopus japonicus.

PubMed

Puthumana, Jayesh; Lee, Min-Chul; Park, Jun Chul; Kim, Hui-Su; Hwang, Dae-Sik; Han, Jeonghoon; Lee, Jae-Seong

2017-03-01

To evaluate the effects of ultraviolet B (UV-B) radiation at the developmental, reproductive, and molecular levels in aquatic invertebrates, we measured UV-B-induced acute toxicity, impairments in developmental and reproductive traits, and UV-B interaction with the entire family of cytochrome P450 (CYP) genes in the intertidal benthic copepod Tigriopus japonicus. We found a significant, dose-dependent reduction (P<0.05) in the survival of T. japonicus that began as a developmental delay and decreased fecundity. The 48h LD10 and LD50 were 1.35 and 1.84kJ/m 2 , and the CYP inhibitor (PBO) elevated mortality, confirming the involvement of CYP genes in UV-B induced toxicity. Low-dose UV-B (1.5kJ/m 2 ) induced developmental delays, and higher doses (6-18kJ/m 2 ) caused reproductive impairments in ovigerous females. The significant up-regulation of CYP genes belonging to clans 2/3/MT/4/20 in T. japonicus exposed to UV-B (12kJ/m 2 ) confirmed molecular interaction between UV-B and CYP genes. Moreover, orphan CYPs, such as CYP20A1, provide good insight on the deorphanization of invertebrate CYPs. Overall, these results demonstrate the involvement of UV-B radiation in the expression of all the CYP genes in T. japonicus and their susceptibility to UV-B radiation. This will provide a better understanding of the mechanistic effects of UV-B in copepods through the predicted AhR-mediated up-regulation of CYP genes. Copyright © 2017 Elsevier B.V. All rights reserved.

Dose-effect of ionizing radiation-induced PIG3 gene expression alteration in human lymphoblastoid AHH-1 cells and human peripheral blood lymphocytes.

PubMed

Liu, Qing-Jie; Zhang, De-Qin; Zhang, Qing-Zhao; Feng, Jiang-Bin; Lu, Xue; Wang, Xin-Ru; Li, Kun-Peng; Chen, De-Qing; Mu, Xiao-Feng; Li, Shuang; Gao, Ling

2015-01-01

To identify new ionizing radiation (IR)-sensitive genes and observe the dose-effect of gene expression alteration (GEA) induced by IR. Microarray was used to screen the differentially expressed genes in human lymphoblastoid cells (AHH-1) using three doses of (60)Co γ-rays (0.5-8 Gy at 1 Gy/min). Given that p53-inducible gene 3 (PIG3) was consistently upregulated, the GEA of PIG3 in AHH-1 cells and human peripheral blood lymphocytes (HPBL) induced by γ-rays (1 Gy/min) was measured at messenger RNA (mRNA) and protein levels. The GEA of PIG3 in AHH-1 cells exposed to neutron radiation (californium-252, 0.073 Gy/min) was also quantified. PIG3 was one of the seven differentially expressed genes found in the microarray analysis. The PIG3 mRNA and protein levels in AHH-1 cells were significantly increased from 1-10 Gy of γ-rays 8-72 h or 8-168 h after exposure, respectively. The enhancement was also observed in AHH-1 cells from 0.4-1.6 Gy of neutrons 48 h post-irradiation. The PIG3 mRNA levels (mRNA copy numbers) in HPBL were significantly increased from 1-8 Gy of γ-rays within 4-24 h post-irradiation, but the highest increase in signal-to-noise responsiveness is approximately two-fold, which was less than that of AHH-1 (approximately 20-fold). IR can upregulate the PIG3 gene expression in AHH-1 and HPBL in the early phase after exposure; however, the IR induced expression levels of PIG3 are greater in AHH-1 than HPBL.

Metformin reduces the endotoxin-induced down-regulation of apolipoprotein E gene expression in macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stavri, Simona; Trusca, Violeta G.; Simionescu, Maya

The atheroprotective role of macrophage-derived apolipoprotein E (apoE) is well known. Our previous reports demonstrated that inflammatory stress down-regulates apoE expression in macrophages, aggravating atherogenesis. Metformin, extensively used as an anti-diabetic drug, has also anti-inflammatory properties, and thus confers vascular protection. In this study, we questioned whether metformin could have an effect on apoE expression in macrophages in normal conditions or under lipopolysaccharide (LPS)-induced stress. The results showed that metformin slightly increases the apoE expression only at high doses (5–10 mM). Low doses of metformin (1–3 mM) significantly reduce the LPS down-regulatory effect on apoE expression in macrophages. Our experiments demonstrated thatmore » LPS-induced NF-κB binds to the macrophage-specific distal regulatory element of apoE gene, namely to the multienhancer 2 (ME.2) and its 5′-deletion fragments. The NF-κB binding on ME.2 and apoE promoter has a down-regulatory effect. In addition, data revealed that metformin impairs NF-κB nuclear translocation, and thus, improves the apoE levels in macrophages under inflammatory stress. The positive effect of metformin in the inflammatory states, its clinical safety and low cost, make this drug a potential adjuvant in the therapeutic strategies for atherosclerosis. - Highlights: • High doses of metformin slightly increase apoE expression in macrophages. • Low doses of metformin up-regulate apoE gene in endotoxin-stressed macrophages. • Metformin reduces the negative effect of LPS on apoE expression by NF-κB inhibition.« less

Transcriptional profiles in liver from mice treated with hepatotumorigenic and nonhepatotumorigenic triazole conazole fungicides: Propiconazole, triadimefon, and myclobutanil.

PubMed

Ward, William O; Delker, Don A; Hester, Susan D; Thai, Sheau-Fung; Wolf, Douglas C; Allen, James W; Nesnow, Stephen

2006-01-01

Conazoles are environmental and pharmaceutical fungicides. The present study relates the toxicological effects of conazoles to alterations of gene and pathway transcription and identifies potential modes of tumorigenic action. In a companion study employing conventional toxicological bioassays (Allen et al., 2006), male CD-1 mice were fed triadimefon, propiconazole, or myclobutanil in a continuous oral-dose regimen for 4, 30, or 90 days. These conazoles were found to induce hepatomegaly, to induce high levels of hepatic pentoxyresorufin-O-dealkylase activity, to increase hepatic cell proliferation, to decrease serum cholesterol, and to increase serum triglycerides. Differentially expressed genes and pathways were identified using Affymetrix GeneChips. Gene-pathway associations were obtained from the Kyoto Encyclopedia of Genes and Genomes, Biocarta, and MetaCore compendia. The pathway profiles of each conazole were different at each time point. In general, the number of altered metabolism, signaling, and growth pathways increased with time and dose and were greatest with propiconazole. All conazoles had effects on nuclear receptors as evidenced by increased expression and enzymatic activities of a series of related cytochrome P450s (CYP). A subset of altered genes and pathways distinguished the three conazoles from each other. Triadimefon and propiconazole both altered apoptosis, cell cycle, adherens junction, calcium signaling, and EGFR signaling pathways. Triadimefon produced greater changes in cholesterol biosynthesis and retinoic acid metabolism genes and in selected signaling pathways. Propiconazole had greater effects on genes responding to oxidative stress and on the IGF/P13K/AKt/PTEN/mTor and Wnt-beta-catenin pathways. In conclusion, while triadimefon, propiconazole, and myclobutanil had similar effects in mouse liver on hepatomegaly, histology, CYP activities, cell proliferation, and serum cholesterol, genomic analyses revealed major differences in their gene expression profiles.

Intra-tumoral gene delivery of feIL-2, feIFN-gamma and feGM-CSF using magnetofection as a neoadjuvant treatment option for feline fibrosarcomas: a phase-I study.

PubMed

Jahnke, A; Hirschberger, J; Fischer, C; Brill, T; Köstlin, R; Plank, C; Küchenhoff, H; Krieger, S; Kamenica, K; Schillinger, U

2007-12-01

Despite aggressive pre- or postoperative treatment, feline fibrosarcomas have a high relapse rate. In this study, a new treatment option based on immune stimulation by intra-tumoral delivery of three feline cytokine genes was performed. The objective of this phase-I dose-escalation study was to determine a safe dose for further evaluation in a subsequent phase-II trial. Twenty-five client-owned cats with clinical diagnosis of fibrosarcoma - primary tumours as well as recurrences - entered the study. Four increasing doses of plasmids coding for feIL-2, feIFN-gamma or feGM-CSF, respectively, were previously defined. In groups I, II, III and IV these doses were 15, 50, 150 and 450 microg per plasmid and a corresponding amount of magnetic nanoparticles. Two preoperative intra-tumoral injections of the magnetic DNA solution were followed by magnetofection. A group of four control cats received only surgical treatment. Side effects were registered and graded according to the VCOG-CTCAE scale and correlated to treatment. Statistical analyses included one-way anova, post hoc and Kruskal-Wallis tests. ELISA tests detecting plasma feIFN-gamma and plasma feGM-CSF were performed. One cat out of group IV (450 microg per plasmid) showed adverse events probably related to gene delivery. As these side effects were self-limiting and occurred only in one of eight cats in group IV, this dose was determined to be well tolerable. Altogether six cats developed local recurrences during a 1-year observation period. Four of these cats had been treated with dose IV. Regarding these observations, a subsequent phase-II trial including a representative amount of cats should be tested for the efficacy of dose IV as well as dose III.

Global gene expression and morphological alterations in the mammary gland after gestational exposure to bisphenol A, genistein and indole-3-carbinol in female Sprague-Dawley offspring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grassi, Tony F.

This study aimed to evaluate the modifying effects of dietary genistein (GEN) and indole-3-carbinol (I3C) on early mammary gland development in female Sprague-Dawley offspring born to mothers exposed to BPA during gestation. Pregnant rats were treated with BPA25 or 250 μg/kg bw/day from gestational days 10 to 21 with or without dietary intake of GEN (250 mg/kg chow) or I3C (2000 mg/kg chow). At post-natal day (PND) 21, female offspring from different litters were euthanized for mammary gland development and gene expression analyses. Our results indicated that prenatal exposure to BPA25 and 250 did not modify the ductal elongation ofmore » the mammary gland tree or the estrogen receptor alpha (ER-α) expression in terminal end buds (TEBs). However, BPA25-exposed offspring had a higher number of terminal structures (TEBs + TDs) and an increased mammary branching and cell proliferation index in TEBs. Besides that, BPA25 and 250 modulated the expression of several genes in the immature mammary gland that were not changed in a dose dependent manner and involved different clusters of up- and down-regulated genes. Furthermore, BPA25 and BPA250 + I3C-treated groups also had a higher number of enriched functional gene categories. In addition, maternal dietary GEN and I3C in association with BPA exposure produced specific gene expression alterations in the mammary gland and overcome the adverse effect of BPA25, decreasing the branching of the mammary gland. In conclusion, prenatal BPA exposure induced both morphological and gene expression modifications on the mammary gland that dietary intake of GEN and I3C reverted on BPA25-exposed animals. - Highlights: • Gestational BPA and its association with GEN and I3C modify gene expression on the early mammary gland development. • GEN and I3C induced a different gene expression signature than lower BPA dose. • Dietary GEN and I3C countered the adverse effect of lower BPA dose on the cell proliferation and mammary gland development.« less

Direct, Differential Effects of Tamoxifen, 4-Hydroxytamoxifen, and Raloxifene on Cardiac Myocyte Contractility and Calcium Handling

PubMed Central

Asp, Michelle L.; Martindale, Joshua J.; Metzger, Joseph M.

2013-01-01

Tamoxifen (Tam), a selective estrogen receptor modulator, is in wide clinical use for the treatment and prevention of breast cancer. High Tam doses have been used for treatment of gliomas and cancers with multiple drug resistance, but long QT Syndrome is a side effect. Tam is also used experimentally in mice for inducible gene knockout in numerous tissues, including heart; however, the potential direct effects of Tam on cardiac myocyte mechanical function are not known. The goal of this study was to determine the direct, acute effects of Tam, its active metabolite 4-hydroxytamoxifen (4OHT), and related drug raloxifene (Ral) on isolated rat cardiac myocyte mechanical function and calcium handling. Tam decreased contraction amplitude, slowed relaxation, and decreased Ca2+ transient amplitude. Effects were primarily observed at 5 and 10 μM Tam, which is relevant for high dose Tam treatment in cancer patients as well as Tam-mediated gene excision in mice. Myocytes treated with 4OHT responded similarly to Tam-treated cells with regard to both contractility and calcium handling, suggesting an estrogen-receptor independent mechanism is responsible for the effects. In contrast, Ral increased contraction and Ca2+ transient amplitudes. At 10 μM, all drugs had a time-dependent effect to abolish cellular contraction. In conclusion, Tam, 4OHT, and Ral adversely and differentially alter cardiac myocyte contractility and Ca2+ handling. These findings have important implications for understanding the Tam-induced cardiomyopathy in gene excision studies and may be important for understanding effects on cardiac performance in patients undergoing high-dose Tam therapy. PMID:24205315

Three-Dimensional Transgenic Cell Models to Quantify Space Genotoxic Effects

NASA Technical Reports Server (NTRS)

Gonda, S.; Wu, H.; Pingerelli, P.; Glickman, B.

2000-01-01

In this paper we describe a three-dimensional, multicellular tissue-equivalent model, produced in NASA-designed, rotating wall bioreactors using mammalian cells engineered for genomic containment of mUltiple copies of defined target genes for genotoxic assessment. The Rat 2(lambda) fibroblasts (Stratagene, Inc.) were genetically engineered to contain high-density target genes for mutagenesis. Stable three-dimensional, multicellular spheroids were formed when human mammary epithelial cells and Rat 2(lambda) fibroblasts were cocultured on Cytodex 3 Beads in a rotating wall bioreactor. The utility of this spheroidal model for genotoxic assessment was indicated by a linear dose response curve and by results of gene sequence analysis of mutant clones from 400micron diameter spheroids following low-dose, high-energy, neon radiation exposure

Tris(1,3-dichloro-2-propyl) phosphate perturbs the expression of genes involved in immune response and lipid and steroid metabolism in chicken embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farhat, Amani; National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3; Buick, Julie K.

We previously demonstrated that in ovo exposure to the flame retardant tris(1,3-dichloro-2-propyl) phosphate (TDCPP) decreased plasma thyroxine levels, reduced growth parameters, and decreased gallbladder size in chicken embryos. In the current study DNA microarrays were used to evaluate global mRNA expression in liver tissue of male chicken embryos that exhibited the above mentioned effects. Injected doses were dimethyl sulfoxide vehicle control, 7.6 or 45 μg TDCPP/g egg. TDCPP caused significant changes in the expression of five genes at the low dose and 47 genes at the high dose (False Discovery Rate p ≤ 0.1, fold change ≥ 1.5). The genemore » expression analysis suggested a compromised immune function, a state of cholestatic liver/biliary fibrosis, and disrupted lipid and steroid metabolism. Circulating bile acid levels were elevated, which is an indication of liver dysfunction, and plasma cholesterol levels were reduced; however, hepatic bile acid and cholesterol levels were unaltered. Interactome analyses identified apolipoprotein E, hepatocyte nuclear factor 4 alpha, and peroxisome proliferator-activated receptor alpha as key regulatory molecules involved in the effects of TDCPP. Our results demonstrate a targeted effect of TDCPP toxicity on lipid metabolism, including cholesterol, that helps explain the aforementioned phenotypic effects, as chicken embryos are highly dependent on yolk lipids for growth and maintenance throughout development. Finally, our results are in concordance with the literature that describes TDCPP as a cancer-causing agent, since the majority of dysregulated genes were involved in cancer pathways. - Highlights: • TDCPP dysregulates genes involved in immune function and lipid metabolism. • A targeted effect of TDCPP toxicity on cholesterol metabolism is apparent. • A state of cholestatic liver fibrosis is suggested by the expression profile. • Elevated plasma bile acids suggest that TDCPP causes liver dysfunction.« less

Suppressive effects of retinoids, carotenoids and antioxidant vitamins on heterocyclic amine-induced umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002).

PubMed

Okai, Y; Higashi-Okai, K; Nakamura, S; Yano, Y; Otani, S

1996-06-12

Effects of retinoids, carotenoids and antioxidant vitamins were studied by mutagen-induced umu C gene expression system in Salmonella typhimurium (TA 1535/pSK 1002). Retinol (vitamin A), retinol acetate and retinoic acid showed remarkable inhibitory activities, whereas retinol palmitate exhibited significant but weak activity for umu C gene expression in tester bacteria induced by 3-amino-3,4-dimethyl-5H-pyrido[4.3-b]indol (Trp-P-1) in the presence of hepatic metabolizing enzymes (S9 mixture). Carotenoids having provitamin A activity (beta-carotene and canthaxanthin) exhibited moderate suppressive effects on the same experimental system. The ranks of suppressive activities were retinol > retinol acetate > retinoic acid > canthaxanthin > beta-carotene > retinol palmitate and their doses for inhibition by 50% (ID50) were estimated to be 1.2 x 10(-7), 3.0 x 10(-7), 5.4 x 10(-7), 1.5 x 10(-6), 4.0 x 10(-5) and 6.0 x 10(-5) M, respectively. However, they did not cause significant inhibition on umu C gene expression induced by direct-acting mutagen (adriamycin or mitomycin C) in the absence of S9 mixture. Inhibition of umu gene expression appears to be due to inhibition of P450-mediated metabolic activation of the heterocyclic amine Trp-P-1. Ascorbic acid (vitamin C) showed weak but significant suppressive activity at high-dose concentrations (3 x 10(-6) - 10(-4)M). However, alpha-tocopherol did not exhibit significant suppression at all dose concentrations. The significance of the experimental results is discussed from the viewpoint of the chemoprevention against genotoxicity associated with carcinogenesis.

Dose-dependent Toxicity of Humanized Renilla reniformis GFP (hrGFP) Limits Its Utility as a Reporter Gene in Mouse Muscle

PubMed Central

Wallace, Lindsay M; Moreo, Andrew; Clark, K Reed; Harper, Scott Q

2013-01-01

Gene therapy has historically focused on delivering protein-coding genes to target cells or tissues using a variety of vectors. In recent years, the field has expanded to include gene-silencing strategies involving delivery of noncoding inhibitory RNAs, such as short hairpin RNAs or microRNAs (miRNAs). Often called RNA interference (RNAi) triggers, these small inhibitory RNAs are difficult or impossible to visualize in living cells or tissues. To circumvent this detection problem and ensure efficient delivery in preclinical studies, vectors can be engineered to coexpress a fluorescent reporter gene to serve as a marker of transduction. In this study, we set out to optimize adeno-associated viral (AAV) vectors capable of delivering engineered miRNAs and green fluorescent protein (GFP) reporter genes to skeletal muscle. Although the more broadly utilized enhanced GFP (eGFP) gene derived from the jellyfish, Aequorea victoria was a conventional choice, we were concerned about some previous studies suggesting this protein was myotoxic. We thus opted to test vectors carrying the humanized Renilla reniformis-derived GFP (hrGFP) gene, which has not seen as extensive usage as eGFP but was purported to be a safer and less cytotoxic alternative. Employing AAV6 vector dosages typically used in preclinical gene transfer studies (3×1010 –1 × 1011 particles), we found that hrGFP caused dose-dependent myopathy when delivered to wild-type (wt) mouse muscle, whereas identical titers of AAV6 carrying eGFP were relatively benign. Dose de-escalation at or below 8 × 109 AAV particles effectively reduced or eliminated hrGFP-associated myotoxicity, but also had dampening effects on green fluorescence and miRNA-mediated gene silencing in whole muscles. We conclude that hrGFP is impractical for use as a transduction marker in preclinical, AAV-based RNA interference therapy studies where adult mouse muscle is the target organ. Moreover, our data support that eGFP is superior to hrGFP as a reporter gene in mouse muscle. These results may impact the design of future preclinical gene therapy studies targeting muscles and non-muscle tissues alike. PMID:23591809

Combined Use of Gene Expression Modeling and siRNA Screening Identifies Genes and Pathways Which Enhance the Activity of Cisplatin When Added at No Effect Levels to Non-Small Cell Lung Cancer Cells In Vitro

PubMed Central

Leung, Ada W. Y.; Hung, Stacy S.; Backstrom, Ian; Ricaurte, Daniel; Kwok, Brian; Poon, Steven; McKinney, Steven; Segovia, Romulo; Rawji, Jenna; Qadir, Mohammed A.; Aparicio, Samuel; Stirling, Peter C.; Steidl, Christian; Bally, Marcel B.

2016-01-01

Platinum-based combination chemotherapy is the standard treatment for advanced non-small cell lung cancer (NSCLC). While cisplatin is effective, its use is not curative and resistance often emerges. As a consequence of microenvironmental heterogeneity, many tumour cells are exposed to sub-lethal doses of cisplatin. Further, genomic heterogeneity and unique tumor cell sub-populations with reduced sensitivities to cisplatin play a role in its effectiveness within a site of tumor growth. Being exposed to sub-lethal doses will induce changes in gene expression that contribute to the tumour cell’s ability to survive and eventually contribute to the selective pressures leading to cisplatin resistance. Such changes in gene expression, therefore, may contribute to cytoprotective mechanisms. Here, we report on studies designed to uncover how tumour cells respond to sub-lethal doses of cisplatin. A microarray study revealed changes in gene expressions that occurred when A549 cells were exposed to a no-observed-effect level (NOEL) of cisplatin (e.g. the IC10). These data were integrated with results from a genome-wide siRNA screen looking for novel therapeutic targets that when inhibited transformed a NOEL of cisplatin into one that induced significant increases in lethality. Pathway analyses were performed to identify pathways that could be targeted to enhance cisplatin activity. We found that over 100 genes were differentially expressed when A549 cells were exposed to a NOEL of cisplatin. Pathways associated with apoptosis and DNA repair were activated. The siRNA screen revealed the importance of the hedgehog, cell cycle regulation, and insulin action pathways in A549 cell survival and response to cisplatin treatment. Results from both datasets suggest that RRM2B, CABYR, ALDH3A1, and FHL2 could be further explored as cisplatin-enhancing gene targets. Finally, pathways involved in repairing double-strand DNA breaks and INO80 chromatin remodeling were enriched in both datasets, warranting further research into combinations of cisplatin and therapeutics targeting these pathways. PMID:26938915

Combined Use of Gene Expression Modeling and siRNA Screening Identifies Genes and Pathways Which Enhance the Activity of Cisplatin When Added at No Effect Levels to Non-Small Cell Lung Cancer Cells In Vitro.

PubMed

Leung, Ada W Y; Hung, Stacy S; Backstrom, Ian; Ricaurte, Daniel; Kwok, Brian; Poon, Steven; McKinney, Steven; Segovia, Romulo; Rawji, Jenna; Qadir, Mohammed A; Aparicio, Samuel; Stirling, Peter C; Steidl, Christian; Bally, Marcel B

2016-01-01

Platinum-based combination chemotherapy is the standard treatment for advanced non-small cell lung cancer (NSCLC). While cisplatin is effective, its use is not curative and resistance often emerges. As a consequence of microenvironmental heterogeneity, many tumour cells are exposed to sub-lethal doses of cisplatin. Further, genomic heterogeneity and unique tumor cell sub-populations with reduced sensitivities to cisplatin play a role in its effectiveness within a site of tumor growth. Being exposed to sub-lethal doses will induce changes in gene expression that contribute to the tumour cell's ability to survive and eventually contribute to the selective pressures leading to cisplatin resistance. Such changes in gene expression, therefore, may contribute to cytoprotective mechanisms. Here, we report on studies designed to uncover how tumour cells respond to sub-lethal doses of cisplatin. A microarray study revealed changes in gene expressions that occurred when A549 cells were exposed to a no-observed-effect level (NOEL) of cisplatin (e.g. the IC10). These data were integrated with results from a genome-wide siRNA screen looking for novel therapeutic targets that when inhibited transformed a NOEL of cisplatin into one that induced significant increases in lethality. Pathway analyses were performed to identify pathways that could be targeted to enhance cisplatin activity. We found that over 100 genes were differentially expressed when A549 cells were exposed to a NOEL of cisplatin. Pathways associated with apoptosis and DNA repair were activated. The siRNA screen revealed the importance of the hedgehog, cell cycle regulation, and insulin action pathways in A549 cell survival and response to cisplatin treatment. Results from both datasets suggest that RRM2B, CABYR, ALDH3A1, and FHL2 could be further explored as cisplatin-enhancing gene targets. Finally, pathways involved in repairing double-strand DNA breaks and INO80 chromatin remodeling were enriched in both datasets, warranting further research into combinations of cisplatin and therapeutics targeting these pathways.

Graves' ophthalmopathy: low-dose dexamethasone reduces retinoic acid receptor-alpha gene expression in orbital fibroblasts.

PubMed

Cury, Sarah Santiloni; Oliveira, Miriane; Síbio, Maria Teresa; Clara, Sueli; Luvizotto, Renata De Azevedo Melo; Conde, Sandro; Jorge, Edson Nacib; Nunes, Vania Dos Santos; Nogueira, Célia Regina; Mazeto, Gláucia Maria Ferreira da Silva

2018-05-17

Graves' ophthalmopathy (GO) is an autoimmune disease that leads to ocular proptosis caused by fat accumulation and inflammation, and the main treatment is corticosteroid therapy. Retinoid acid receptor-alpha (RARα) seems to be associated with inflammation and adipocyte differentiation. This study aimed to assess the effect of glucocorticoid treatment on orbital fibroblasts of GO patient treated or not with different glucocorticoid doses. Orbital fibroblasts collected during orbital decompression of a female patient with moderately severe/severe GO were cultivated and treated with 10 nM and 100 nM dexamethasone (Dex). rRARα gene expression in the treated and untreated cells was then compared. Fibroblast RARα expression was not affected by 100 nM Dex. On the other hand, RARα expression was 24% lower in cells treated with 10 nM Dex (p < 0.05). Orbital fibroblasts from a GO patient expressed the RARα gene, which was unaffected by higher, but decreased with lower doses of glucocorticoid.

VITELLOGENIN GENE EXPRESSION IN FATHEAD MINNOWS AND PEARL DACE FROM CONTROL (NON-DOSED) AND LAKES DOSED WITH EE2 IN THE CANADIAN EXPERIMENTAL LAKES AREA

EPA Science Inventory

A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA) in northwestern Ontario for three years beginning in 2001. This experiment examined population, organismal, biochemical and cellular-level effects in la...

A Candidate Gene Analysis of Methylphenidate Response in Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

McGough, James J.; McCracken, James T.; Loo, Sandra K.; Manganiello, Marc; Leung, Michael C.; Tietjens, Jeremy R.; Trinh, Thao; Baweja, Shilpa; Suddath, Robert; Smalley, Susan L.; Hellemann, Gerhard; Sugar, Catherine A.

2009-01-01

Objective: This study examines the potential role of candidate genes in moderating treatment effects of methylphenidate (MPH) in attention-deficit/hyperactivity disorder (ADHD). Method: Eighty-two subjects with ADHD aged 6 to 17 years participated in a prospective, double-blind, placebo-controlled, multiple-dose, crossover titration trial of…

Tea polysaccharide inhibits RANKL-induced osteoclastogenesis in RAW264.7 cells and ameliorates ovariectomy-induced osteoporosis in rats.

PubMed

Xu, Huanhuan; Yin, Dan; Liu, Titi; Chen, Fei; Chen, Yingli; Wang, Xuanjun; Sheng, Jun

2018-06-01

Tea drinking has positive effects on bone health and may prevent and treat osteoporosis, especially in older and postmenopausal women. Tea polysaccharide (TPS) is a major bioactive constituent in tea. Despite its profound effects on human health, whether TPS has anti-osteoporotic effects remains largely unknown. As such, we investigated the anti-osteoporotic effects of TPS. In vitro, TPS effects on osteoclastogenesis were examined using osteoclast precursor RAW264.7 cells. TPS effects on osteoclastogenesis-related expression of marker genes and proteins were determined by gene expression and immunoblotting analyses, respectively. For in vivo studies, 12-week-old female Wistar rats were divided randomly into a sham-operated group (sham) and four ovariectomized (OVX) subgroups: OVX with vehicle (model) and OVX with low-, medium-, and high-dose TPS (0.32, 0.64 and 1.28 g/kg body weight/day, respectively). TPS was administered intragastrically to rats for 13 weeks. Body weight, blood biochemical parameters, organ weight, organ coefficients, femoral length, bone mineral density (BMD), biomechanical properties, and bone microarchitecture were documented. TPS inhibited osteoclast differentiation significantly and dose-dependently, and its inhibitory effect was not due to toxicity to RAW264.7 cells. TPS suppressed expression of osteoclastogenesis-related marker genes and proteins significantly. In in vivo studies, medium-dose TPS treatment ameliorated OVX-induced calcium loss significantly. Low-dose TPS treatment decreased the activity of acid phosphatase (ACP) in OVX rats significantly. In addition, TPS treatment improved other blood biochemical parameters and femoral biomechanical properties to a certain extent. More importantly, TPS treatment ameliorated bone microarchitecture in OVX rats strikingly because of increased cortical bone thickness and trabecular bone area in the femur. TPS can inhibit receptor activator nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis in RAW264.7 cells and ameliorate ovariectomy-induced osteoporosis in rats. Copyright © 2018. Published by Elsevier Masson SAS.

Evaluation of the reversal of multidrug resistance by MDR1 ribonucleic acid interference in a human colon cancer model using a Renilla luciferase reporter gene and coelenterazine.

PubMed

Jeon, Yong Hyun; Bae, Seon-ae; Lee, Yong Jin; Lee, You La; Lee, Sang-Woo; Yoon, Ghil-Suk; Ahn, Byeong-Cheol; Ha, Jeoung-Hee; Lee, Jaetae

2010-12-01

The reversal effect of multidrug resistance (MDR1) gene expression by adenoviral vector-mediated MDR1 ribonucleic acid interference was assessed in a human colon cancer animal model using bioluminescent imaging with Renilla luciferase (Rluc) gene and coelenterazine, a substrate for Rluc or MDR1 gene expression. A fluorescent microscopic examination demonstrated an increased green fluorescent protein signal in Ad-shMDR1- (recombinant adenovirus that coexpressed MDR1 small hairpin ribonucleic acid [shRNA] and green fluorescent protein) infected HCT-15/Rluc cells in a virus dose-dependent manner. Concurrently, with an increasing administered virus dose (0, 15, 30, 60, and 120 multiplicity of infection), Rluc activity was significantly increased in Ad-shMDR1-infected HCT-15/Rluc cells in a virus dose-dependent manner. In vivo bioluminescent imaging showed about 7.5-fold higher signal intensity in Ad-shMDR1-infected tumors than in control tumors (p < .05). Immunohistologic analysis demonstrated marked reduction of P-glycoprotein expression in infected tumor but not in control tumor. In conclusion, the reversal of MDR1 gene expression by MDR1 shRNA was successfully evaluated by bioluminescence imaging with Rluc activity using an in vivo animal model with a multidrug resistance cancer xenograft.

Photobiomodulation therapy protects skeletal muscle and improves muscular function of mdx mice in a dose-dependent manner through modulation of dystrophin.

PubMed

Albuquerque-Pontes, Gianna Móes; Casalechi, Heliodora Leão; Tomazoni, Shaiane Silva; Serra, Andrey Jorge; Ferreira, Cheila de Sousa Bacelar; Brito, Rodrigo Barbosa de Oliveira; de Melo, Brunno Lemes; Vanin, Adriane Aver; Monteiro, Kadma Karênina Damasceno Soares; Dellê, Humberto; Frigo, Lucio; Marcos, Rodrigo Labat; de Carvalho, Paulo de Tarso Camillo; Leal-Junior, Ernesto Cesar Pinto

2018-05-01

This study aimed to analyze the protective effects of photobiomodulation therapy (PBMT) with combination of low-level laser therapy (LLLT) and light emitting diode therapy (LEDT) on skeletal muscle tissue to delay dystrophy progression in mdx mice (DMD mdx ). To this aim, mice were randomly divided into five different experimental groups: wild type (WT), placebo-control (DMD mdx ), PBMT with doses of 1 J (DMD mdx ), 3 J (DMD mdx ), and 10 J (DMD mdx ). PBMT was performed employing a cluster probe with 9 diodes (1 x 905nm super-pulsed laser diode; 4 x 875nm infrared LEDs; and 4 x 640nm red LEDs, manufactured by Multi Radiance Medical®, Solon - OH, USA), 3 times a week for 14 weeks. PBMT was applied on a single point (tibialis anterior muscle-bilaterally). We analyzed functional performance, muscle morphology, and gene and protein expression of dystrophin. PBMT with a 10 J dose significantly improved (p < 0.001) functional performance compared to all other experimental groups. Muscle morphology was improved by all PBMT doses, with better outcomes with the 3 and 10 J doses. Gene expression of dystrophin was significantly increased with 3 J (p < 0.01) and 10 J (p < 0.01) doses when compared to placebo-control group. Regarding protein expression of dystrophin, 3 J (p < 0.001) and 10 J (p < 0.05) doses also significantly showed increase compared to placebo-control group. We conclude that PBMT can mainly preserve muscle morphology and improve muscular function of mdx mice through modulation of gene and protein expression of dystrophin. Furthermore, since PBMT is a non-pharmacological treatment which does not present side effects and is easy to handle, it can be seen as a promising tool for treating Duchenne's muscular dystrophy.

The pharmacogenetics and pharmacodynamics of clopidogrel response: an analysis from the PRINC (Plavix Response in Coronary Intervention) trial.

PubMed

Gladding, Patrick; Webster, Mark; Zeng, Irene; Farrell, Helen; Stewart, Jim; Ruygrok, Peter; Ormiston, John; El-Jack, Seif; Armstrong, Guy; Kay, Patrick; Scott, Douglas; Gunes, Arzu; Dahl, Marja-Liisa

2008-12-01

This study assessed the effect of pharmacogenetics on the antiplatelet effect of clopidogrel. Variability in clopidogrel response might be influenced by polymorphisms in genes coding for drug metabolism enzymes (cytochrome P450 [CYP] family), transport proteins (P-glycoprotein) and/or target proteins for the drug (adenosine diphosphate-receptor P2Y12). Sixty patients undergoing elective percutaneous coronary intervention in the randomized PRINC (Plavix Response in Coronary Intervention) trial had platelet function measured using the VerifyNow P2Y12 analyzer after a 600-mg or split 1,200-mg loading dose and after a 75- or 150-mg daily maintenance dosage. Polymerase chain reaction-based genotyping evaluated polymorphisms in the CYP2C19, CYP2C9, CYP3A4, CYP3A5, ABCB1, P2Y12, and CES genes. CYP2C19*1*1 carriers had greater platelet inhibition 2 h after a 600-mg dose (median: 23%, range: 0% to 66%), compared with platelet inhibition in CYP2C19*2 or *4 carriers (10%, 0% to 56%, p = 0.029) and CYP2C19*17 carriers (9%, 0% to 98%, p = 0.026). CYP2C19*2 or *4 carriers had greater platelet inhibition with the higher loading dose than with the lower dose at 4 h (37%, 8% to 87% vs. 14%, 0% to 22%, p = 0.002) and responded better with the higher maintenance dose regimen (51%, 15% to 86% vs. 14%, 0% to 67%, p = 0.042). Carriers of the CYP2C19*2 and *4 alleles showed reduced platelet inhibition after a clopidogrel 600-mg loading dose but responded to higher loading and maintenance dose regimens. Genotyping for the relevant gene polymorphisms may help to individualize and optimize clopidogrel treatment. (Australia New Zealand Clinical Trials Registry; ACTRN12606000129583).

“Stockpile” of Slight Transcriptomic Changes Determines the Indirect Genotoxicity of Low-Dose BPA in Thyroid Cells

PubMed Central

Porreca, Immacolata; Ulloa Severino, Luisa; D’Angelo, Fulvio; Cuomo, Danila; Ceccarelli, Michele; Altucci, Lucia; Amendola, Elena; Nebbioso, Angela; Mallardo, Massimo

2016-01-01

Epidemiological and experimental data highlighted the thyroid-disrupting activity of bisphenol A (BPA). Although pivotal to identify the mechanisms of toxicity, direct low-dose BPA effects on thyrocytes have not been assessed. Here, we report the results of microarray experiments revealing that the transcriptome reacts dynamically to low-dose BPA exposure, adapting the changes in gene expression to the exposure duration. The response involves many genes, enriching specific pathways and biological functions mainly cell death/proliferation or DNA repair. Their expression is only slightly altered but, since they enrich specific pathways, this results in major effects as shown here for transcripts involved in the DNA repair pathway. Indeed, even though no phenotypic changes are induced by the treatment, we show that the exposure to BPA impairs the cell response to further stressors. We experimentally verify that prolonged exposure to low doses of BPA results in a delayed response to UV-C-induced DNA damage, due to impairment of p21-Tp53 axis, with the BPA-treated cells more prone to cell death and DNA damage accumulation. The present findings shed light on a possible mechanism by which BPA, not able to directly cause genetic damage at environmental dose, may exert an indirect genotoxic activity. PMID:26982218

Peripheral Blood Signatures of Lead Exposure

PubMed Central

LaBreche, Heather G.; Meadows, Sarah K.; Nevins, Joseph R.; Chute, John P.

2011-01-01

Background Current evidence indicates that even low-level lead (Pb) exposure can have detrimental effects, especially in children. We tested the hypothesis that Pb exposure alters gene expression patterns in peripheral blood cells and that these changes reflect dose-specific alterations in the activity of particular pathways. Methodology/Principal Finding Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in the peripheral blood of female Balb/c mice following exposure to per os lead acetate trihydrate or plain drinking water for two weeks and after a two-week recovery period. Data sets were RMA-normalized and dose-specific signatures were generated using established methods of supervised classification and binary regression. Pathway activity was analyzed using the ScoreSignatures module from GenePattern. Conclusions/Significance The low-level Pb signature was 93% sensitive and 100% specific in classifying samples a leave-one-out crossvalidation. The high-level Pb signature demonstrated 100% sensitivity and specificity in the leave-one-out crossvalidation. These two signatures exhibited dose-specificity in their ability to predict Pb exposure and had little overlap in terms of constituent genes. The signatures also seemed to reflect current levels of Pb exposure rather than past exposure. Finally, the two doses showed differential activation of cellular pathways. Low-level Pb exposure increased activity of the interferon-gamma pathway, whereas high-level Pb exposure increased activity of the E2F1 pathway. PMID:21829687

Progesterone up-regulates vasodilator effects of calcitonin gene-related peptide in N(G)-nitro-L-arginine methyl ester-induced hypertension.

PubMed

Gangula, P R; Wimalawansa, S J; Yallampalli, C

1997-04-01

We recently reported that calcitonin gene-related peptide can reverse the hypertension produced by N(G)-nitro-L-arginine methyl ester in pregnant rats. In the current study we investigated whether these vasodilator effects of calcitonin gene-related peptide were progesterone dependent. Calcitonin gene-related peptide or N(G)-nitro-L-arginine methyl ester was infused through osmotic minipumps, either separately or in combination, to groups of five pregnant rats from day 17 of gestation until day 8 post partum or to nonpregnant ovariectomized rats for 8 days. Progesterone was injected during days 1 to 6 post partum and for 6 days after ovariectomy. Systolic blood pressure was measured daily. Animals receiving N(G)-nitro-L-arginine methyl ester exhibited significant elevations of blood pressure during pregnancy and post partum. Coadministration of calcitonin gene-related peptide to these rats reversed the hypertension during pregnancy but not during the postpartum period. At the dose used in this study calcitonin gene-related peptide administered alone was without significant effects on blood pressure. However, it reduced both the mortality and growth restriction of the fetus associated with N(G)-nitro-L-arginine methyl ester in these animals. Calcitonin gene-related peptide reversed the hypertension in N(G)-nitro-L-arginine methyl ester-infused postpartum rats during the periods of progesterone treatment only, and these effects were lost when progesterone treatment was stopped. Neither progesterone nor calcitonin gene-related peptide alone were effective. To further confirm these observations, progesterone effects were tested in ovariectomized adult rats. Similar to the findings in postpartum rats, calcitonin gene-related peptide completely reversed the elevation in blood pressure in N(G)-nitro-L-arginine methyl ester-treated rats receiving progesterone injections. The effects of calcitonin gene-related peptide were apparent only during the progesterone treatment period, and these effects were lost when progesterone treatment was stopped. Again, at these doses calcitonin gene-related peptide and progesterone were each ineffective alone. Calcitonin gene-related peptide reverses the N(G)-nitro-L-arginine methyl ester-induced hypertension during pregnancy, when progesterone levels are elevated, but not post partum or in ovariectomized nonpregnant rats. The blood pressure-lowering effects of calcitonin gene-related peptide were restored in both postpartum and ovariectomized rats with progesterone treatment. Therefore we conclude that progesterone modulates vasodilator effects of calcitonin gene-related peptide in hypertensive rats.

Gene expression changes in honey bees induced by sublethal imidacloprid exposure during the larval stage.

PubMed

Wu, Ming-Cheng; Chang, Yu-Wen; Lu, Kuang-Hui; Yang, En-Cheng

2017-09-01

Honey bee larvae exposed to sublethal doses of imidacloprid show behavioural abnormalities as adult insects. Previous studies have demonstrated that this phenomenon originates from abnormal neural development in response to imidacloprid exposure. Here, we further investigated the global gene expression changes in the heads of newly emerged adults and observed that 578 genes showed more than 2-fold changes in gene expression after imidacloprid exposure. This information might aid in understanding the effects of pesticides on the health of pollinators. For example, the genes encoding major royal jelly proteins (MRJPs), a group of multifunctional proteins with significant roles in the sustainable development of bee colonies, were strongly downregulated. These downregulation patterns were further confirmed through analyses using quantitative reverse transcription-polymerase chain reaction on the heads of 6-day-old nurse bees. To our knowledge, this study is the first to demonstrate that sublethal doses of imidacloprid affect mrjp expression and likely weaken bee colonies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Oleanolic acid alters bile acid metabolism and produces cholestatic liver injury in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Jie, E-mail: JLiu@kumc.edu; Zunyi Medical College, Zunyi 563003; Lu, Yuan-Fu

2013-11-01

Oleanolic acid (OA) is a triterpenoids that exists widely in plants. OA is effective in protecting against hepatotoxicants. Whereas a low dose of OA is hepatoprotective, higher doses and longer-term use of OA produce liver injury. This study characterized OA-induced liver injury in mice. Adult C57BL/6 mice were given OA at doses of 0, 22.5, 45, 90, and 135 mg/kg, s.c., daily for 5 days, and liver injury was observed at doses of 90 mg/kg and above, as evidenced by increases in serum activities of alanine aminotransferase and alkaline phosphatase, increases in serum total bilirubin, as well as by livermore » histopathology. OA-induced cholestatic liver injury was further evidenced by marked increases of both unconjugated and conjugated bile acids (BAs) in serum. Gene and protein expression analysis suggested that livers of OA-treated mice had adaptive responses to prevent BA accumulation by suppressing BA biosynthetic enzyme genes (Cyp7a1, 8b1, 27a1, and 7b1); lowering BA uptake transporters (Ntcp and Oatp1b2); and increasing a BA efflux transporter (Ostβ). OA increased the expression of Nrf2 and its target gene, Nqo1, but decreased the expression of AhR, CAR and PPARα along with their target genes, Cyp1a2, Cyp2b10 and Cyp4a10. OA had minimal effects on PXR and Cyp3a11. Taken together, the present study characterized OA-induced liver injury, which is associated with altered BA homeostasis, and alerts its toxicity potential. - Highlights: • Oleanolic acid at higher doses and long-term use may produce liver injury. • Oleanolic acid increased serum ALT, ALP, bilirubin and bile acid concentrations. • OA produced feathery degeneration, inflammation and cell death in the liver. • OA altered bile acid homeostasis, affecting bile acid synthesis and transport.« less

Comparative Analysis of AhR-Mediated TCDD-Elicited Gene Expression in Human Liver Adult Stem Cells

PubMed Central

Kim, Suntae; Dere, Edward; Burgoon, Lyle D.; Chang, Chia-Cheng; Zacharewski, Timothy R.

2009-01-01

Time course and dose-response studies were conducted in HL1-1 cells, a human liver cell line with stem cell–like characteristics, to assess the differential gene expression elicited by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) compared with other established models. Cells were treated with 0.001, 0.01, 0.1, 1, 10, or 100nM TCDD or dimethyl sulfoxide vehicle control for 12 h for the dose-response study, or with 10nM TCDD or vehicle for 1, 2, 4, 8, 12, 24, or 48 h for the time course study. Elicited changes were monitored using a human cDNA microarray with 6995 represented genes. Empirical Bayes analysis identified 144 genes differentially expressed at one or more time points following treatment. Most genes exhibited dose-dependent responses including CYP1A1, CYP1B1, ALDH1A3, and SLC7A5 genes. Comparative analysis of HL1-1 differential gene expression to human HepG2 data identified 74 genes with comparable temporal expression profiles including 12 putative primary responses. HL1-1–specific changes were related to lipid metabolism and immune responses, consistent with effects elicited in vivo. Furthermore, comparative analysis of HL1-1 cells with mouse Hepa1c1c7 hepatoma cell lines and C57BL/6 hepatic tissue identified 18 and 32 commonly regulated orthologous genes, respectively, with functions associated with signal transduction, transcriptional regulation, metabolism and transport. Although some common pathways are affected, the results suggest that TCDD elicits species- and model-specific gene expression profiles. PMID:19684285

Administration of low dose methamphetamine 12 h after a severe traumatic brain injury prevents neurological dysfunction and cognitive impairment in rats.

PubMed

Rau, Thomas F; Kothiwal, Aakriti S; Rova, Annela R; Brooks, Diane M; Rhoderick, Joseph F; Poulsen, Austin J; Hutchinson, Jim; Poulsen, David J

2014-03-01

We recently published data that showed low dose of methamphetamine is neuroprotective when delivered 3 h after a severe traumatic brain injury (TBI). In the current study, we further characterized the neuroprotective potential of methamphetamine by determining the lowest effective dose, maximum therapeutic window, pharmacokinetic profile and gene expression changes associated with treatment. Graded doses of methamphetamine were administered to rats beginning 8 h after severe TBI. We assessed neuroprotection based on neurological severity scores, foot fault assessments, cognitive performance in the Morris water maze, and histopathology. We defined 0.250 mg/kg/h as the lowest effective dose and treatment at 12 h as the therapeutic window following severe TBI. We examined gene expression changes following TBI and methamphetamine treatment to further define the potential molecular mechanisms of neuroprotection and determined that methamphetamine significantly reduced the expression of key pro-inflammatory signals. Pharmacokinetic analysis revealed that a 24-hour intravenous infusion of methamphetamine at a dose of 0.500 mg/kg/h produced a plasma Cmax value of 25.9 ng/ml and a total exposure of 544 ng/ml over a 32 hour time frame. This represents almost half the 24-hour total exposure predicted for a daily oral dose of 25mg in a 70 kg adult human. Thus, we have demonstrated that methamphetamine is neuroprotective when delivered up to 12 h after injury at doses that are compatible with current FDA approved levels. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Mechanisms of colitis-accelerated colon carcinogenesis and its prevention with the combination of aspirin and curcumin: Transcriptomic analysis using RNA-seq.

PubMed

Guo, Yue; Su, Zheng-Yuan; Zhang, Chengyue; Gaspar, John M; Wang, Rui; Hart, Ronald P; Verzi, Michael P; Kong, Ah-Ng Tony

2017-07-01

Colorectal cancer (CRC) remains the leading cause of cancer-related death in the world. Aspirin (ASA) and curcumin (CUR) are widely investigated chemopreventive candidates for CRC. However, the precise mechanisms of their action and their combinatorial effects have not been evaluated. The purpose of the present study was to determine the effect of ASA, CUR, and their combination in azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-accelerated colorectal cancer (CAC). We also aimed to characterize the differential gene expression profiles in AOM/DSS-induced tumors as well as in tumors modulated by ASA and CUR using RNA-seq. Diets supplemented with 0.02% ASA, 2% CUR or 0.01% ASA+1% CUR were given to mice from 1week prior to the AOM injection until the experiment was terminated 22weeks after AOM initiation. Our results showed that CUR had a superior inhibitory effect in colon tumorigenesis compared to that of ASA. The combination of ASA and CUR at a lower dose exhibited similar efficacy to that of a higher dose of CUR at 2%. RNA isolated from colonic tissue from the control group and from tumor samples from the experimental groups was subjected to RNA-seq. Transcriptomic analysis suggested that the low-dose combination of ASA and CUR modulated larger gene sets than the single treatment. These differentially expressed genes were situated in several canonical pathways important in the inflammatory network and liver metastasis in CAC. We identified a small subset of genes as potential molecular targets involved in the preventive action of the combination of ASA and CUR. Taken together, the current results provide the first evidence in support of the chemopreventive effect of a low-dose combination of ASA and CUR in CAC. Moreover, the transcriptional profile obtained in our study may provide a framework for identifying the mechanisms underlying the carcinogenesis process from normal colonic tissue to tumor development as well as the cancer inhibitory effects and potential molecular targets of ASA and CUR. Copyright © 2017 Elsevier Inc. All rights reserved.

A Comparison of Gene Expression of Decorin and MMP13 in Hypertrophic Scars Treated With Calcium Channel Blocker, Steroid, and Interferon: A Human-Scar-Carrying Animal Model Study.

PubMed

Yang, Shih-Yi; Yang, Jui-Yung; Hsiao, Yen-Chang; Chuang, Shiow-Shuh

2017-01-01

The formation of hypertrophic scaring (HSc) is an abnormal wound-healing response. In a previous study, an animal model with human scar tissue implanted into nude mice (BALB/c) has been successfully established. The effects of verapamil as well as combination therapy with verapamil and kenacort have been studied and compared. To treat persistent hypertrophic scars, local injection of drugs composed of steroids, calcium channel blockers (CCBs), and interferon might be a good method. What is the best dose of the regimen and what are the mechanisms are also a worthwhile study. Scar specimens were harvested from patients with HSc or Keloid resulting from burn injury, and then implanted to BALB/c-nu nude mice for 4 weeks. Before implantation, the specimen was either injected with or without drugs such as steroids (kenacort), CCBs (verapamil), and interferons (INFα2b), respectively. After the removal of implants, quantitative gene expressions of decorin and collagenase (MMP13) were measured using a real-time polymerase chain reaction to detect their mRNAs. Two way-ANOVA and Post Hoc were used for statistical analysis using the software SPSS 15.0. All drug-treated groups increased the expressions of decorin and MMP13 in comparison with those in noninjected group (p < .001) in a dose-dependent manner. Comparing equal amounts of individual drugs, gene expression of decorin was increased with increasing injection amount, and the best result in low amount of injection (0.02 mL of each) was shown in the group injected with INFα2b followed by kenacort and verapamil. However, the results were changed while injection amount was up to 0.04 mL and the strongest decorin gene expression was found in kenacort injection. Regarding MMP-13 expression, low-amount injection (0.02 mL) of INFα2b has strongest gene expression followed by kenacort and verapamil, but in the large-amount regimes (0.04 mL), verapamil had strongest gene expression followed by INFα2b and kenacort. This study showed that the kenacort, verapamil, and INFα2b all inhibited HSc in a dose-dependent manner through the evidence of gene expression of decorin and MMP13. In comparison with the injections between small amounts of drugs, INFα2b potentiated the strongest decorin and MMP13 expression. On the contrary, among the large-amount injection regimes, kenacrot was more effective on decorin expression as verapamil to MMP13 expression. To decrease side effects from the drugs and produce promising results for the clinical practice, it is suggested to maintain the dose of INFα2b along with an increased dose of verapamil for HSc improvement.

Gene signature of the post-Chernobyl papillary thyroid cancer.

PubMed

Handkiewicz-Junak, Daria; Swierniak, Michal; Rusinek, Dagmara; Oczko-Wojciechowska, Małgorzata; Dom, Genevieve; Maenhaut, Carine; Unger, Kristian; Detours, Vincent; Bogdanova, Tetiana; Thomas, Geraldine; Likhtarov, Ilya; Jaksik, Roman; Kowalska, Malgorzata; Chmielik, Ewa; Jarzab, Michal; Swierniak, Andrzej; Jarzab, Barbara

2016-07-01

Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure.

Synergistic Effects of Incubation in Rotating Bioreactors and Cumulative Low Dose 60Co γ-ray Irradiation on Human Immortal Lymphoblastoid Cells

NASA Astrophysics Data System (ADS)

Wei, Lijun; Han, Fang; Yue, Lei; Zheng, Hongxia; Yu, Dan; Ma, Xiaohuan; Cheng, Huifang; Li, Yu

2012-11-01

The complex space environments can influence cell structure and function. The research results on space biology have shown that the major mutagenic factors in space are microgravity and ionizing radiation. In addition, possible synergistic effects of radiation and microgravity on human cells are not well understood. In this study, human immortal lymphoblastoid cells were established from human peripheral blood lymphocytes and the cells were treated with low dose (0.1, 0.15 and 0.2 Gy) cumulative 60Co γ-irradiation and simulated weightlessness [obtained by culturing cells in the Rotating Cell Culture System (RCCS)]. The commonly used indexes of cell damage such as micronucleus rate, cell cycle and mitotic index were studied. Previous work has proved that Gadd45 (growth arrest and DNA-damage-inducible protein 45) gene increases with a dose-effect relationship, and will possibly be a new biological dosimeter to show irradiation damage. So Gadd45 expression is also detected in this study. The micronucleus rate and the expression of Gadd45α gene increased with irradiation dose and were much higher after incubation in the rotating bioreactor than that in the static irradiation group, while the cell proliferation after incubation in the rotating bioreactor decreased at the same time. These results indicate synergetic effects of simulated weightlessness and low dose irradiation in human cells. The cell damage inflicted by γ-irradiation increased under simulated weightlessness. Our results suggest that during medium- and long-term flight, the human body can be damaged by cumulative low dose radiation, and the damage will even be increased by microgravity in space.

Dose–response relationships in gene expression profiles in rainbow trout, Oncorhyncus mykiss, exposed to ethynylestradiol

PubMed Central

Hook, Sharon E.; Skillman, Ann D.; Small, Jack A.; Schultz, Irvin R.

2008-01-01

Determining how gene expression profiles change with toxicant dose will improve the utility of arrays in identifying biomarkers and modes of toxic action. Isogenic rainbow trout, Oncorhyncus mykiss, were exposed to 10, 50 or 100 ng/L ethynylestradiol (a xeno-estrogen) for 7 days. Following exposure hepatic RNA was extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNAs. Transcript expression in treated vs control fish was analyzed via Genespring (Silicon Genetics) to identify genes with altered expression, as well as to determine gene clustering patterns that can be used as “expression signatures”. Array results were confirmed via qRT PCR. Our analysis indicates that gene expression profiles varied somewhat with dose. Established biomarkers of exposure to estrogenic chemicals, such as vitellogenin, vitelline envelope proteins, and the estrogen receptor alpha, were induced at every dose. Other genes were dose specific, suggesting that diffierent doses induce distinct physiological responses. These findings demonstrate that cDNA microarrays could be used to identify both toxicant class and relative dose. PMID:16725192

Doxycycline Impairs Mitochondrial Function and Protects Human Glioma Cells from Hypoxia-Induced Cell Death: Implications of Using Tet-Inducible Systems.

PubMed

Luger, Anna-Luisa; Sauer, Benedikt; Lorenz, Nadja I; Engel, Anna L; Braun, Yannick; Voss, Martin; Harter, Patrick N; Steinbach, Joachim P; Ronellenfitsch, Michael W

2018-05-17

Inducible gene expression is an important tool in molecular biology research to study protein function. Most frequently, the antibiotic doxycycline is used for regulation of so-called tetracycline (Tet)-inducible systems. In contrast to stable gene overexpression, these systems allow investigation of acute and reversible effects of cellular protein induction. Recent reports have already called for caution when using Tet-inducible systems as the employed antibiotics can disturb mitochondrial function and alter cellular metabolism by interfering with mitochondrial translation. Reprogramming of energy metabolism has lately been recognized as an important emerging hallmark of cancer and is a central focus of cancer research. Therefore, the scope of this study was to systematically analyze dose-dependent metabolic effects of doxycycline on a panel of glioma cell lines with concomitant monitoring of gene expression from Tet-inducible systems. We report that doxycycline doses commonly used with inducible expression systems (0.01⁻1 µg/mL) substantially alter cellular metabolism: Mitochondrial protein synthesis was inhibited accompanied by reduced oxygen and increased glucose consumption. Furthermore, doxycycline protected human glioma cells from hypoxia-induced cell death. An impairment of cell growth was only detectable with higher doxycycline doses (10 µg/mL). Our findings describe settings where doxycycline exerts effects on eukaryotic cellular metabolism, limiting the employment of Tet-inducible systems.

Agmatine attenuates methamphetamine-induced passive avoidance learning and memory and CaMKII-α gene expression deteriorations in hippocampus of rat.

PubMed

Noorbakhshnia, Maryam; Rashidkaboli, Arsham; Pakatchian, Mahnaz; Beheshti, Siamak

2018-06-13

Methamphetamine (METH) abuse is one the most worldwide problems with wide-ranging effects on the central nervous system (CNS). Chronic METH abuse can associate with cognitive abnormalities and neurodegenerative changes in the brain. Agmatine, a cationic polyamine, has been proposed as a neuromodulator that modulates many effects of abused drugs. The aim of this study was to determine if agmatine can decrease the impairment effect of METH on memory and hippocampal CaMKII-α gene expression, a gene that plays a major role in memory. Male wistar rats (200-220 g) were allocated into 7 groups, including 5 groups of saline, METH (1, 2 mg/kg), Agmatine (5, 10 mg/kg) and 2 groups of agmatine (5, 10 mg/kg) with higher doses of METH (2 mg/kg) for 5 consecutive days (n = 8 in each group). All injections were done intraperitoneally and agmatine was administrated 10 min before METH treatment. Furthermore, Passive avoidance learning (PAL) test was assessed on the 5th day. Retention test was done 24 h after training and the rats were sacrificed immediately. Hippocampi were removed and stored at -80 °C. Finally, hippocampal CaMKII-α gene expression was measured using Quantitative Real-time PCR. Our data showed that chronic METH dose-dependently impaired PAL retrieval, as it decreased step-through latency (STL) and increased time spent in the dark compartment (TDC). While Agmatine with a higher dose (10 mg/kg) significantly decreased impairment effect of METH (2 mg/kg) on PAL and memory. Also, molecular results revealed that METH (2 mg/kg) markedly decreased hippocampal CaMKII-α gene expression while agmatine (10 mg/kg) coadminstration prevented it. Taken together, the results propose that agmatine may provide a potential therapy for learning and memory deficits induced by METH. Copyright © 2017. Published by Elsevier Inc.

Radiation Exposure Alters Expression of Metabolic Enzyme Genes In Mice

NASA Technical Reports Server (NTRS)

Wotring, Virginia E.; Mangala, L. S.; Zhang, Y.; Wu, H.

2010-01-01

Most pharmaceuticals are metabolized by the liver. The health of the liver, especially the rate of its metabolic enzymes, determines the concentration of circulating drugs as well as the duration of their efficacy. Because of the importance of the liver in drug metabolism it is important to understand the effects of spaceflight on the enzymes of the liver. Exposure to cosmic radiation is one aspect of spaceflight that can be modeled in ground experiments. This study is an effort to examine the effects of adaptive mechanisms that may be triggered by early exposure to low radiation doses. Using procedures approved by the JSC Animal Care & Use Committee, C57 male mice were exposed to Cs-137 in groups: controls, low dose (50 mGy), high dose (6Gy) and a fourth group that received both radiation doses separated by 24 hours. Animals were anesthetized and sacrificed 4 hours after their last radiation exposure. Livers were removed immediately and flash-frozen in liquid nitrogen. Tissue was homogenized, RNA extracted and purified (Absolutely RNA, Agilent). Quality of RNA samples was evaluated (Agilent Bioanalyzer 2100). Complementary DNA was prepared from high-quality RNA samples, and used to run RT-qPCR screening arrays for DNA Repair and Drug Metabolism (SuperArray, SABiosciences/Qiagen; BioRad Cfx96 qPCR System). Of 91 drug metabolism genes examined, expression of 7 was altered by at least one treatment condition. Genes that had elevated expression include those that metabolize promethazine and steroids (4-8-fold), many that reduce oxidation products, and one that reduces heavy metal exposure (greater than 200-fold). Of the 91 DNA repair and general metabolism genes examined, expression of 14 was altered by at least one treatment condition. These gene expression changes are likely homeostatic and could lead to development of new radioprotective countermeasures.

Upregulation of RGS2: a new mechanism for pirfenidone amelioration of pulmonary fibrosis.

PubMed

Xie, Yan; Jiang, Haihong; Zhang, Qian; Mehrotra, Suneet; Abel, Peter W; Toews, Myron L; Wolff, Dennis W; Rennard, Stephen; Panettieri, Reynold A; Casale, Thomas B; Tu, Yaping

2016-08-22

Pirfenidone was recently approved for treatment of idiopathic pulmonary fibrosis. However, the therapeutic dose of pirfenidone is very high, causing side effects that limit its doses and therapeutic effectiveness. Understanding the molecular mechanisms of action of pirfenidone could improve its safety and efficacy. Because activated fibroblasts are critical effector cells associated with the progression of fibrosis, this study investigated the genes that change expression rapidly in response to pirfenidone treatment of pulmonary fibroblasts and explored their contributions to the anti-fibrotic effects of pirfenidone. We used the GeneChip microarray to screen for genes that were rapidly up-regulated upon exposure of human lung fibroblast cells to pirfenidone, with confirmation for specific genes by real-time PCR and western blots. Biochemical and functional analyses were used to establish their anti-fibrotic effects in cellular and animal models of pulmonary fibrosis. We identified Regulator of G-protein Signaling 2 (RGS2) as an early pirfenidone-induced gene. Treatment with pirfenidone significantly increased RGS2 mRNA and protein expression in both a human fetal lung fibroblast cell line and primary pulmonary fibroblasts isolated from patients without or with idiopathic pulmonary fibrosis. Pirfenidone treatment or direct overexpression of recombinant RGS2 in human lung fibroblasts inhibited the profibrotic effects of thrombin, whereas loss of RGS2 exacerbated bleomycin-induced pulmonary fibrosis and mortality in mice. Pirfenidone treatment reduced bleomycin-induced pulmonary fibrosis in wild-type but not RGS2 knockout mice. Endogenous RGS2 exhibits anti-fibrotic functions. Upregulated RGS2 contributes significantly to the anti-fibrotic effects of pirfenidone.

Phenolic compounds apigenin, hesperidin and kaempferol reduce in vitro lipid accumulation in human adipocytes.

PubMed

Gómez-Zorita, Saioa; Lasa, Arrate; Abendaño, Naiara; Fernández-Quintela, Alfredo; Mosqueda-Solís, Andrea; Garcia-Sobreviela, Maria Pilar; Arbonés-Mainar, Jose M; Portillo, Maria P

2017-11-21

Adipocytes derived from human mesenchymal stem cells (MSCs) are widely used to investigate adipogenesis. Taking into account both the novelty of these MSCs and the scarcity of studies focused on the effects of phenolic compounds, the aim of the present study was to analyze the effect of apigenin, hesperidin and kaempferol on pre-adipocyte and mature adipocytes derived from this type of cells. In addition, the expression of genes involved in TG accumulation was also measured. Pre-adipocytes were cultured from day 0 to day 8 and mature adipocytes for 48 h with the polyphenols at doses of 1, 10 and 25 µM. Apigenin did not show an anti-adipogenic action. Pre-adipocytes treated with hesperidin and kaempferol showed reduced TG content at the three experimental doses. Apigenin did not modify the expression of the main adipogenic genes (c/ebpβ, c/ebpα, pparγ and srebp1c), hesperidin inhibited genes involved in the three phases of adipogenesis (c/ebpβ, srebp1c and perilipin) and kaempferol reduced c/ebpβ. In mature adipocytes, the three polyphenols reduced TG accumulation at the dose of 25 µM, but not at lower doses. All compounds increased mRNA levels of atgl. Apigenin and hesperidin decreased fasn expression. The present study shows the anti-adipogenic effect and delipidating effects of apigenin, hesperidin and kaempferol in human adipocytes derived from hMSCs. While hesperidin blocks all the stages of adipogenesis, kaempferol only inhibits the early stage. Regarding mature adipocytes, the three compounds reduce TG accumulation by activating, at least in part, lipolysis, and in the case of hesperidin and apigenin, also by reducing lipogenesis. The present study shows for the first time the anti-adipogenic effect and delipidating effect of apigenin, hesperidin and kaempferol in human adipocytes derived from MSCs for the first time.

[Effect of Buzhong Yiqi decoction on PI3K and AKT in spleen, stomach and lung of nude mice with lung adenocarcinoma transplantation tumor].

PubMed

Liu, Ya-Li; Wang, Ying; Yi, Jia-Li; Jing, Huan; Liu, Chun-Ying

2014-05-01

To explore the effect of Buzhong Yiqi decoction on PI3K/AKT signaling pathway in spleen, stomach and lung of nude mice with lung adenocarcinoma transplantation tumor. Totally 60 nude mice were randomly divided into the blank control group, the tumor-bearing control group, the cisplatin group, the low-dose Buzhong Yiqi decoction group, the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group. After the corresponding interventions, efforts were made to measure the transplanted tumor volume and calculate the tumor inhibiting rate. The immunohistochemical method and real time PCR were used to detect the expression of PI3K and AKT level in nude mice spleen, stomach and lung. Buzhong Yiqi decoction of different concentrations combined with cisplatin could inhibit the growth of the transplanted tumor, with the strongest inhibitory effect in the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group. All of the expressions of PI3K and AKT protein and gene in the spleen, stomach and lung increased, with the most significant increase in the tumor-bearing group. Along with the increase of the concentration of cisplatin and Buzhong Yiqi decoction, the expressions of PI3K and AKT gradually reduced. Compared with the tumor-bearing control group, there were statistical differences in spleen and stomach tissues (P < 0.05). Compared with the cisplatin group, the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group showed statistical differences (P < 0.05), but without statistical difference compared with the blank control group. Among nude mice with lung adenocarcinoma transplantation tumor, the PI3K and AKT protein and gene expressions in spleen, stomach and lung tissues increased, which might indicated the effect of cisplatin and Buzhong Yiqi decoction in reducing PI3K and AKT expressions and the relations between the reduction degree and the concentrations of Buzhong Yiqi decoction. Cisplatin combined with Buzhong Yiqi decoction could decrease the PI3K and AKT protein and gene expression in spleen, stomach and lung, and make the pathway closer to normal, so as to protect the functions of spleen, stomach and lung, there may be target spots of Buzhong Yiqi decoction in PI3K/AKT signal pathway.

Minimal doses of a sequence-optimized transgene mediate high-level and long-term EPO expression in vivo: challenging CpG-free gene design.

PubMed

Kosovac, D; Wild, J; Ludwig, C; Meissner, S; Bauer, A P; Wagner, R

2011-02-01

Advanced gene delivery techniques can be combined with rational gene design to further improve the efficiency of plasmid DNA (pDNA)-mediated transgene expression in vivo. Herein, we analyzed the influence of intragenic sequence modifications on transgene expression in vitro and in vivo using murine erythropoietin (mEPO) as a transgene model. A single electro-gene transfer of an RNA- and codon-optimized mEPOopt gene into skeletal muscle resulted in a 3- to 4-fold increase of mEPO production sustained for >1 year and triggered a significant increase in hematocrit and hemoglobin without causing adverse effects. mEPO expression and hematologic levels were significantly lower when using comparable amounts of the wild type (mEPOwt) gene and only marginal effects were induced by mEPOΔCpG lacking intragenic CpG dinucleotides, even at high pDNA amounts. Corresponding with these observations, in vitro analysis of transfected cells revealed a 2- to 3-fold increased (mEPOopt) and 50% decreased (mEPOΔCpG) erythropoietin expression compared with mEPOwt, respectively. RNA analyses demonstrated that the specific design of the transgene sequence influenced expression levels by modulating transcriptional activity and nuclear plus cytoplasmic RNA amounts rather than translation. In sum, whereas CpG depletion negatively interferes with efficient expression in postmitotic tissues, mEPOopt doses <0.5 μg were sufficient to trigger optimal long-term hematologic effects encouraging the use of sequence-optimized transgenes to further reduce effective pDNA amounts.

A Comparison of Molecular and Histopathological Changes in Mouse Intestinal Tissue Following Whole-Body Proton- or Gamma-Irradiation

NASA Technical Reports Server (NTRS)

Purgason, Ashley; Mangala, Lingegowda; Zhang, Ye; Hamilton, Stanley; Wu, Honglu

2010-01-01

There are many consequences following exposure to the space radiation environment which can adversely affect the health of a crew member. Acute radiation syndrome (ARS) involving nausea and vomiting, damage to radio-sensitive tissue such as the blood forming organs and gastrointestinal tract, and cancer are some of these negative effects. The space radiation environment is ample with protons and contains gamma rays as well. Little knowledge exists to this point, however, regarding the effects of protons on mammalian systems; conversely several studies have been performed observing the effects of gamma rays on different animal models. For the research presented here, we wish to compare our previous work looking at whole-body exposure to protons using a mouse model to our studies of mice experiencing whole-body exposure to gamma rays as part of the radio-adaptive response. Radio-adaptation is a well-documented phenomenon in which cells exposed to a priming low dose of radiation prior to a higher dose display a reduction in endpoints like chromosomal aberrations, cell death, micronucleus formation, and more when compared to their counterparts receiving high dose-irradiation only. Our group has recently completed a radio-adaptive experiment with C57BL/6 mice. For both this study and the preceding proton research, the gastrointestinal tract of each animal was dissected four hours post-irradiation and the isolated small intestinal tissue was fixed in formalin for histopathological examination or snap-frozen in liquid nitrogen for RNA isolation. Histopathologic observation of the tissue using standard H&E staining methods to screen for morphologic changes showed an increase in apoptotic lesions for even the lowest doses of 0.1 Gy of protons and 0.05 Gy of gamma rays, and the percentage of apoptotic cells increased with increasing dose. A smaller percentage of crypts showed 3 or more apoptotic lesions in animals that received 6 Gy of gamma-irradiation compared to mice receiving only 2 Gy of protons. Tissue of the gastrointestinal tract was also homogenized and RNA was isolated for cDNA synthesis and real-time PCR analysis. Inspecting apoptotic lesions of the duodenum of the small intestine as an endpoint of damage did not reveal a radio-adaptive response in C57BL/6 mice at the four hour time point. Results of gene expression changes showed consistent up or down regulation of a number of genes for all of the exposure doses that may play a role in proton-induced apoptosis. Preliminary results of gene expression alterations as a result of gamma-irradiation revealed a wealth of genes involved in oxidative stress and antioxidant defense processes being up- or down-regulated only at the highest exposure dose of 6 Gy and the combined dose of 5 cGy with 6 Gy. Those animals undergoing only 5 cGy of gamma-irradiation showed very little modification of gene expression. Taken together these results lead us to conclude that protons cause more severe morphologic damage to the duodenum of the small intestine at a dose of 2 Gy than a higher dose of 6 Gy of gamma rays to the same organ. Both protons and gamma rays lead to significant variation in gene expression at high doses in the small intestine and these changes may provide insight into the mechanism of injury seen in the gastrointestinal tract following radiation exposure. Astronauts experiencing prolonged exposure to protons in the low Earth orbit and in deep space, and experiencing acute exposure to protons from solar particle events, may face biological consequences that will impact a mission s success. We will continue this work by studying, quantifying, and comparing damage due to protons and gamma rays in the small intestine as well as other organs in a time-dependent manner.

Anti-photoaging potential of propolis extract in UVB-irradiated human dermal fibroblasts through increasing the expression of FOXO3A and NGF genes.

PubMed

Ebadi, Parimah; Fazeli, Mehdi

2017-11-01

Propolis is a resinous compound that has been widely used in folk medicine. Different biological activities and therapeutic applications of propolis have been studied before. However, the effects of propolis on longevity-associated genes expression in the prevention of skin photoaging still remained unclear. Therefore in this study the protective effects of propolis on the expressions of two longevity-associated genes, FOXO3A and NGF genes, against UVB-induced photoaging in human dermal fibroblasts (HDF) were investigated. Propolis extract demonstrated a concentration-dependent free radical scavenging activity that was determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Also, Folin-Ciocalteu method was used to measure the total phenolic content of the extract. The viability of HDF cells was decreased gradually with increasing UVB radiation doses and 248mJ/cm 2 was selected as the sub-cytotoxic dose. Pre-treatment with propolis extract increased the viability of UVB-irradiated human dermal fibroblasts and decreased the number of β-galactosidase positive cells as senescent cells among them. It also increased the expression of FOXO3A and NGF genes in irradiated and non-irradiated cells. Consequently, these findings suggest that propolis extract has anti-photoaging potential and this property, in addition to its strong antioxidant activity, may be due to its effects on upregulation of longevity-associated genes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

[Cytokine-mediated regulation of expression of Gfi1 and U2afll4 genes activated by T-cells with different differentiation status in vitro].

PubMed

Yurova, K A; Sokhonevich, N A; Khaziakhmatova, O G; Litvinova, L S

2016-01-01

The dose-dependent effects of cytokines (IL-2, IL-7, and IL-15), which have a common g-chain, on mRNA expression of U2afll4 and GFi1 genes involved in regulation of alternative splicing of the Ptprc gene, have been investigated in vitro using T-lymphocyte cultures with different degrees of differentiation. IL-2, IL-7, and IL-15 caused a similar unidirectional inhibitory effect of various severity on restimulated CD45RO+ T-cells exposed to an antigen-independent activation; they caused a dose-dependent decrease of the U2af1l4 gene expression, and an increase of Gfi1 gene expression. This may suggest formation of active forms of the CD45 receptor, and also limitation of the formation of low-molecular short splice variants of the CD45RO receptor. Under conditions of antigen-independent stimulation of naive CD45RA+-cells rIL-7 and IL-15 exhibited opposite effects on U2af1l4 and Gfi1 gene expression. The increase of IL-7 concentrations in the incubation medium of naive cells was accompanied by a decrease in expression of both genes. IL-15 IL-7 exhibited opposite effects. Cytokines possessing a common g-chain (IL-2, IL-7, and IL-15) prevented antigen-independent differentiation of naive T-cells, by preventing the formation of polyclonal "surrogate" cells. In general, the study of the molecular mechanisms of genetic control determining homeostatic processes of T-cells in response to exposure to antigenic or non-antigenic treatments may be important for construction of a general model of self-maintenance and differentiation of immune cells.

Radiation- and Age-Associated Changes in Peripheral Blood Dendritic Cell Populations among Aging Atomic Bomb Survivors in Japan.

PubMed

Kajimura, Junko; Lynch, Heather E; Geyer, Susan; French, Benjamin; Yamaoka, Mika; Shterev, Ivo D; Sempowski, Gregory D; Kyoizumi, Seishi; Yoshida, Kengo; Misumi, Munechika; Ohishi, Waka; Hayashi, Tomonori; Nakachi, Kei; Kusunoki, Yoichiro

2017-11-30

Previous immunological studies in atomic bomb survivors have suggested that radiation exposure leads to long-lasting changes, similar to immunological aging observed in T-cell-adaptive immunity. However, to our knowledge, late effects of radiation on dendritic cells (DCs), the key coordinators for activation and differentiation of T cells, have not yet been investigated in humans. In the current study, we hypothesized that numerical and functional decreases would be observed in relationship to radiation dose in circulating conventional DCs (cDCs) and plasmacytoid DCs (pDCs) among 229 Japanese A-bomb survivors. Overall, the evidence did not support this hypothesis, with no overall changes in DCs or functional changes observed with radiation dose. Multivariable regression analysis for radiation dose, age and gender effects revealed that total DC counts as well as subpopulation counts decreased in relationship to increasing age. Further analyses revealed that in women, absolute numbers of pDCs showed significant decreases with radiation dose. A hierarchical clustering analysis of gene expression profiles in DCs after Toll-like receptor stimulation in vitro identified two clusters of participants that differed in age-associated expression levels of genes involved in antigen presentation and cytokine/chemokine production in cDCs. These results suggest that DC counts decrease and expression levels of gene clusters change with age. More than 60 years after radiation exposure, we also observed changes in pDC counts associated with radiation, but only among women.

Radiation- and Age-Associated Changes in Peripheral Blood Dendritic Cell Populations among Aging Atomic Bomb Survivors in Japan.

PubMed

Kajimura, Junko; Lynch, Heather E; Geyer, Susan; French, Benjamin; Yamaoka, Mika; Shterev, Ivo D; Sempowski, Gregory D; Kyoizumi, Seishi; Yoshida, Kengo; Misumi, Munechika; Ohishi, Waka; Hayashi, Tomonori; Nakachi, Kei; Kusunoki, Yoichiro

2018-01-01

Previous immunological studies in atomic bomb survivors have suggested that radiation exposure leads to long-lasting changes, similar to immunological aging observed in T-cell-adaptive immunity. However, to our knowledge, late effects of radiation on dendritic cells (DCs), the key coordinators for activation and differentiation of T cells, have not yet been investigated in humans. In the current study, we hypothesized that numerical and functional decreases would be observed in relationship to radiation dose in circulating conventional DCs (cDCs) and plasmacytoid DCs (pDCs) among 229 Japanese A-bomb survivors. Overall, the evidence did not support this hypothesis, with no overall changes in DCs or functional changes observed with radiation dose. Multivariable regression analysis for radiation dose, age and gender effects revealed that total DC counts as well as subpopulation counts decreased in relationship to increasing age. Further analyses revealed that in women, absolute numbers of pDCs showed significant decreases with radiation dose. A hierarchical clustering analysis of gene expression profiles in DCs after Toll-like receptor stimulation in vitro identified two clusters of participants that differed in age-associated expression levels of genes involved in antigen presentation and cytokine/chemokine production in cDCs. These results suggest that DC counts decrease and expression levels of gene clusters change with age. More than 60 years after radiation exposure, we also observed changes in pDC counts associated with radiation, but only among women.

In Utero Exposure to Di-(2-Ethylhexyl) Phthalate Induces Testicular Effects in Neonatal Rats That Are Antagonized by Genistein Cotreatment1

PubMed Central

Jones, Steven; Boisvert, Annie; Francois, Sade; Zhang, Liandong; Culty, Martine

2015-01-01

Fetal exposure to endocrine disruptors (EDs) is believed to predispose males to reproductive abnormalities. Although males are exposed to combinations of chemicals, few studies have evaluated the effects of ED mixtures at environmentally relevant doses. Our previous work showed that fetal exposure to a mixture of the phytoestrogen genistein (GEN) and the plasticizer di-(2-ethylhexyl) phthalate (DEHP) induced unique alterations in adult testis. In this follow-up study, we examined Postnatal Day 3 (PND3) and PND6 male offspring exposed from Gestational Day 14 to parturition to corn oil, 10mg/kg GEN, DEHP, or their combination, to gain insight into the early molecular events driving long-term alterations. DEHP stimulated the mRNA and protein expression of the steroidogenic enzyme HSD3B, uniquely at PND3. DEHP also increased the mRNA expression of Nestin, a Leydig progenitor/Sertoli cell marker, and markers of Sertoli cell (Wt1), gonocyte (Plzf, Foxo1), and proliferation (Pcna) at PND3, while these genes were unchanged by the mixture. Redox (Nqo1, Sod2, Sod3, Trx, Gst, Cat) and xenobiotic transporter (Abcb1b, Abcg2) gene expression was also increased by DEHP at PND3, while attenuated when combined with GEN, suggesting the involvement of cellular stress in short-term DEHP effects and a protective effect of GEN. The direct effects of GEN and mono-(2-ethylhexyl) phthalate, the principal bioactive metabolite of DEHP, on testis were investigated in PND3 organ cultures, showing a stimulatory effect of 10 μM mono-(2-ethylhexyl) phthalate on basal testosterone production that was normalized by GEN. These effects contrasted with previous reports of androgen suppression and decreased gene expression in perinatal rat testis by high DEHP doses, implying that neonatal effects are not predictive of adult effects. We propose that GEN, through an antioxidant action, normalizes reactive oxygen species-induced neonatal effects of DEHP. The notion that these EDs do not follow classical dose-response effects and involve different mechanisms of toxicity from perinatal ages to adulthood highlights the importance of assessing impacts across a range of doses and ages. PMID:26316063

Benchmark Dose Modeling Estimates of the Concentrations of Inorganic Arsenic That Induce Changes to the Neonatal Transcriptome, Proteome, and Epigenome in a Pregnancy Cohort.

PubMed

Rager, Julia E; Auerbach, Scott S; Chappell, Grace A; Martin, Elizabeth; Thompson, Chad M; Fry, Rebecca C

2017-10-16

Prenatal inorganic arsenic (iAs) exposure influences the expression of critical genes and proteins associated with adverse outcomes in newborns, in part through epigenetic mediators. The doses at which these genomic and epigenomic changes occur have yet to be evaluated in the context of dose-response modeling. The goal of the present study was to estimate iAs doses that correspond to changes in transcriptomic, proteomic, epigenomic, and integrated multi-omic signatures in human cord blood through benchmark dose (BMD) modeling. Genome-wide DNA methylation, microRNA expression, mRNA expression, and protein expression levels in cord blood were modeled against total urinary arsenic (U-tAs) levels from pregnant women exposed to varying levels of iAs. Dose-response relationships were modeled in BMDExpress, and BMDs representing 10% response levels were estimated. Overall, DNA methylation changes were estimated to occur at lower exposure concentrations in comparison to other molecular endpoints. Multi-omic module eigengenes were derived through weighted gene co-expression network analysis, representing co-modulated signatures across transcriptomic, proteomic, and epigenomic profiles. One module eigengene was associated with decreased gestational age occurring alongside increased iAs exposure. Genes/proteins within this module eigengene showed enrichment for organismal development, including potassium voltage-gated channel subfamily Q member 1 (KCNQ1), an imprinted gene showing differential methylation and expression in response to iAs. Modeling of this prioritized multi-omic module eigengene resulted in a BMD(BMDL) of 58(45) μg/L U-tAs, which was estimated to correspond to drinking water arsenic concentrations of 51(40) μg/L. Results are in line with epidemiological evidence supporting effects of prenatal iAs occurring at levels <100 μg As/L urine. Together, findings present a variety of BMD measures to estimate doses at which prenatal iAs exposure influences neonatal outcome-relevant transcriptomic, proteomic, and epigenomic profiles.

p53 activated by AND gate genetic circuit under radiation and hypoxia for targeted cancer gene therapy

PubMed Central

Ding, Miao; Li, Rong; He, Rong; Wang, Xingyong; Yi, Qijian; Wang, Weidong

2015-01-01

Radio-activated gene therapy has been developed as a novel therapeutic strategy against cancer; however, expression of therapeutic gene in peritumoral tissues will result in unacceptable toxicity to normal cells. To restrict gene expression in targeted tumor mass, we used hypoxia and radiation tolerance features of tumor cells to develop a synthetic AND gate genetic circuit through connecting radiation sensitivity promoter cArG6, heat shock response elements SNF1, HSF1 and HSE4 with retroviral vector plxsn. Their construction and dynamic activity process were identified through downstream enhanced green fluorescent protein and wtp53 expression in non-small cell lung cancer A549 cells and in a nude mice model. The result showed that AND gate genetic circuit could be activated by lower required radiation dose (6 Gy) and after activated, AND gate could induce significant apoptosis effects and growth inhibition of cancer cells in vitro and in vivo. The radiation- and hypoxia-activated AND gate genetic circuit, which could lead to more powerful target tumoricidal activity represented a promising strategy for both targeted and effective gene therapy of human lung adenocarcinoma and low dose activation character of the AND gate genetic circuit implied that this model could be further exploited to decrease side-effects of clinical radiation therapy. PMID:26177264

Prevalence of combinatorial CYP2C9 and VKORC1 genotypes in Puerto Ricans: implications for warfarin management in Hispanics.

PubMed

Duconge, Jorge; Cadilla, Carmen L; Windemuth, Andreas; Kocherla, Mohan; Gorowski, Krystyna; Seip, Richard L; Bogaard, Kali; Renta, Jessica Y; Piovanetti, Paola; D'Agostino, Darrin; Santiago-Borrero, Pedro J; Ruaño, Gualberto

2009-01-01

Polymorphisms in the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) genes significantly alter the effective warfarin dose. We determined the frequencies of alleles, single carriers, and double carriers of single nucleotide polymorphisms (SNPs) in the CYP2C9 and VKORC1 genes in a Puerto Rican cohort and gauged the impact of these polymorphisms on warfarin dosage using a published algorithm. A total of 92 DNA samples were genotyped using Luminex x-MAP technology. The polymorphism frequencies were 6.52%, 5.43% and 28.8% for CYP2C9 *2, *3 and VKORC1-1639 C>A polymorphisms, respectively. The prevalence of combinatorial genotypes was 16% for carriers of both the CYP2C9 and VKORC1 polymorphisms, 9% for carriers of CYP2C9 polymorphisms, 35% for carriers of the VKORC1 polymorphism, and the remaining 40% were non-carriers for either gene. Based on a published warfarin dosing algorithm, single, double and triple carriers of functionally deficient polymorphisms predict reductions of 1.0-1.6, 2.0-2.9, and 2.9-3.7 mg/day, respectively, in warfarin dose. Overall, 60% of the population carried at least a single polymorphism predicting deficient warfarin metabolism or responsiveness and 13% were double carriers with polymorphisms in both genes studied. Combinatorial genotyping of CYP2C9 and VKORC1 can allow for individualized dosing of warfarin among patients with gene polymorphisms, potentially reducing the risk of stroke or bleeding.

A transcriptomics data-driven gene space accurately predicts liver cytopathology and drug-induced liver injury

PubMed Central

Kohonen, Pekka; Parkkinen, Juuso A.; Willighagen, Egon L.; Ceder, Rebecca; Wennerberg, Krister; Kaski, Samuel; Grafström, Roland C.

2017-01-01

Predicting unanticipated harmful effects of chemicals and drug molecules is a difficult and costly task. Here we utilize a ‘big data compacting and data fusion’—concept to capture diverse adverse outcomes on cellular and organismal levels. The approach generates from transcriptomics data set a ‘predictive toxicogenomics space’ (PTGS) tool composed of 1,331 genes distributed over 14 overlapping cytotoxicity-related gene space components. Involving ∼2.5 × 108 data points and 1,300 compounds to construct and validate the PTGS, the tool serves to: explain dose-dependent cytotoxicity effects, provide a virtual cytotoxicity probability estimate intrinsic to omics data, predict chemically-induced pathological states in liver resulting from repeated dosing of rats, and furthermore, predict human drug-induced liver injury (DILI) from hepatocyte experiments. Analysing 68 DILI-annotated drugs, the PTGS tool outperforms and complements existing tests, leading to a hereto-unseen level of DILI prediction accuracy. PMID:28671182

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate–Dependent Manner

PubMed Central

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR. PMID:29531508

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate-Dependent Manner.

PubMed

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR.

Effects of a water-soluble curcumin protein conjugate vs. pure curcumin in a diabetic model of erectile dysfunction.

PubMed

Abdel Aziz, Mohamed Talaat; Motawi, Tarek; Rezq, Ameen; Mostafa, Taymour; Fouad, Hanan H; Ahmed, Hanan H; Rashed, Laila; Sabry, Dina; Senbel, Amira; Al-Malki, A; El-Shafiey, Raghda

2012-07-01

Curcumin is involved in erectile signaling via elevation of cyclic guanosine monophosphate (cGMP). Assessment of the effects of water-soluble curcumin in erectile dysfunction (ED). One hundred twenty male white albino rats were divided into: 1st and 2nd control groups with or without administration of Zinc protoporphyrin (ZnPP), 3rd and 4th diabetic groups with or without ZnPP, 5th diabetic group on single oral dose of pure curcumin, 6th diabetic group on pure curcumin administered daily for 12 weeks, 7th and 8th diabetic groups on single dose of water-soluble curcumin administered with or without ZnPP, 9th and 10th diabetic groups on water-soluble curcumin administered daily for 12 weeks with or without ZnPP. All curcumin dosage schedules were administered after induction of diabetes. Quantitative gene expression of endothelial nitric oxide synthase (eNOS), neuronal NOS (nNOS), inducible NOS (iNOS), heme oxygenase-1 (HO-1), nuclear transcription factor-erythroid2 (Nrf2), NF-Кβ, and p38. Cavernous tissue levels of HO and NOS enzyme activities, cGMP and intracavernosal pressure (ICP). Twelve weeks after induction of diabetes, ED was confirmed by the significant decrease in ICP. There was a significant decrease in cGMP, NOS, HO enzymes, a significant decrease in eNOS, nNOS, HO-1 genes and a significant elevation of NF-Кβ, p38, iNOS genes. Administration of pure curcumin or its water-soluble conjugate led to a significant elevation in ICP, cGMP levels, a significant increase in HO-1 and NOS enzymes, a significant increase in eNOS, nNOS, HO-1, and Nrf2 genes, and a significant decrease in NF-Кβ, p38, and iNOS genes. Water-soluble curcumin showed significant superiority and more prolonged duration of action. Repeated doses regimens were superior to single dose regimen. Administration of ZnPP significantly reduced HO enzyme, cGMP, ICP/ mean arterial pressure (MAP), HO-1 genes in diabetic groups. Water-soluble curcumin could enhance erectile function with more effectiveness and with more prolonged duration of action. © 2012 International Society for Sexual Medicine.

Transcriptome analysis reveals novel insights into the response of low-dose benzo(a)pyrene exposure in male tilapia.

PubMed

Colli-Dula, Reyna Cristina; Fang, Xiefan; Moraga-Amador, David; Albornoz-Abud, Nacira; Zamora-Bustillos, Roberto; Conesa, Ana; Zapata-Perez, Omar; Moreno, Diego; Hernandez-Nuñez, Emanuel

2018-06-08

Despite a wide number of toxicological studies that describe benzo[a]pyrene (BaP) effects, the metabolic mechanisms that underlie these effects in fish are largely unknown. Of great concern is the presence of BaP in aquatic systems, especially those in close proximity to human activity leading to consumption of potentially contaminated foods. BaP is a known carcinogen and it has been reported to have adverse effects on the survival, development and reproduction of fish. The purpose of this study was to investigate if a low dose of BaP can alter genes and key metabolic pathways in the liver and testis in male adult tilapia, and whether these could be associated with biological endpoints disruption. We used both high-throughput RNA-Sequencing to assess whole genome gene expression following repeated intraperitoneal injections of 3 mg/kg of BaP (every 6 days for 26 days) and morphometric endpoints as indicators of general health. Condition factor (K) along with hepatosomatic and gonadosomatic indices (morphometric parameters) were significantly lower in BaP-treated fish than in controls. BaP exposure induced important changes in the gene expression pattern in liver and testis as revealed by both Pathway and Gene Ontology (GO) analyses. Alterations that were shared by both tissues included arachidonic acid metabolism, androgen receptor to prostate-specific antigen signaling, and insulin-associated effects on lipogenesis. The most salient liver-specific effects included: biological processes involved in detoxification, IL6-associated insulin resistance, mTOR hyperactivation, mitotic cytokinesis, spindle pole and microtubule binding. BaP effects that were confined to the testis included: immune system functions, inflammatory response, estrogen and androgen metabolic pathways. Taken together, gene expression and morphometric end point data indicate that the reproductive success of adult male tilapia could be compromised as a result of BaP exposure. These results constitute new insights on the mechanism of action of low dose BaP in a non-model organism (tilapia). Copyright © 2018 Elsevier B.V. All rights reserved.

Synchrotron phase-contrast X-ray imaging reveals fluid dosing dynamics for gene transfer into mouse airways.

PubMed

Donnelley, M; Siu, K K W; Jamison, R A; Parsons, D W

2012-01-01

Although airway gene transfer research in mouse models relies on bolus fluid dosing into the nose or trachea, the dynamics and immediate fate of delivered gene transfer agents are poorly understood. In particular, this is because there are no in vivo methods able to accurately visualize the movement of fluid in small airways of intact animals. Using synchrotron phase-contrast X-ray imaging, we show that the fate of surrogate fluid doses delivered into live mouse airways can now be accurately and non-invasively monitored with high spatial and temporal resolution. This new imaging approach can help explain the non-homogenous distributions of gene expression observed in nasal airway gene transfer studies, suggests that substantial dose losses may occur at deliver into mouse trachea via immediate retrograde fluid motion and shows the influence of the speed of bolus delivery on the relative targeting of conducting and deeper lung airways. These findings provide insight into some of the factors that can influence gene expression in vivo, and this method provides a new approach to documenting and analyzing dose delivery in small-animal models.

Effect of the Deletion of Genes Encoding Proteins of the Extracellular Virion Form of Vaccinia Virus on Vaccine Immunogenicity and Protective Effectiveness in the Mouse Model

PubMed Central

Meseda, Clement A.; Campbell, Joseph; Kumar, Arunima; Garcia, Alonzo D.; Merchlinsky, Michael; Weir, Jerry P.

2013-01-01

Antibodies to both infectious forms of vaccinia virus, the mature virion (MV) and the enveloped virion (EV), as well as cell-mediated immune response appear to be important for protection against smallpox. EV virus particles, although more labile and less numerous than MV, are important for dissemination and spread of virus in infected hosts and thus important in virus pathogenesis. The importance of the EV A33 and B5 proteins for vaccine induced immunity and protection in a murine intranasal challenge model was evaluated by deletion of both the A33R and B5R genes in a vaccine-derived strain of vaccinia virus. Deletion of either A33R or B5R resulted in viruses with a small plaque phenotype and reduced virus yields, as reported previously, whereas deletion of both EV protein-encoding genes resulted in a virus that formed small infection foci that were detectable and quantifiable only by immunostaining and an even more dramatic decrease in total virus yield in cell culture. Deletion of B5R, either as a single gene knockout or in the double EV gene knockout virus, resulted in a loss of EV neutralizing activity, but all EV gene knockout viruses still induced a robust neutralizing activity against the vaccinia MV form of the virus. The effect of elimination of A33 and/or B5 on the protection afforded by vaccination was evaluated by intranasal challenge with a lethal dose of either vaccinia virus WR or IHD-J, a strain of vaccinia virus that produces relatively higher amounts of EV virus. The results from multiple experiments, using a range of vaccination doses and virus challenge doses, and using mortality, morbidity, and virus dissemination as endpoints, indicate that the absence of A33 and B5 have little effect on the ability of a vaccinia vaccine virus to provide protection against a lethal intranasal challenge in a mouse model. PMID:23785523

Dose-dense and less dose-intense Total Therapy 5 for gene expression profiling-defined high-risk multiple myeloma.

PubMed

Jethava, Y; Mitchell, A; Zangari, M; Waheed, S; Schinke, C; Thanendrarajan, S; Sawyer, J; Alapat, D; Tian, E; Stein, C; Khan, R; Heuck, C J; Petty, N; Avery, D; Steward, D; Smith, R; Bailey, C; Epstein, J; Yaccoby, S; Hoering, A; Crowley, J; Morgan, G; Barlogie, B; van Rhee, F

2016-07-29

Multiple myeloma (MM) is a heterogeneous disease with high-risk patients progressing rapidly despite treatment. Various definitions of high-risk MM are used and we reported that gene expression profile (GEP)-defined high risk was a major predictor of relapse. In spite of our best efforts, the majority of GEP70 high-risk patients relapse and we have noted higher relapse rates during drug-free intervals. This prompted us to explore the concept of less intense drug dosing with shorter intervals between courses with the aim of preventing inter-course relapse. Here we report the outcome of the Total Therapy 5 trial, where this concept was tested. This regimen effectively reduced early mortality and relapse but failed to improve progression-free survival and overall survival due to relapse early during maintenance.

Time- and dose-dependent differential regulation of copper-zinc superoxide dismutase and manganese superoxide dismutase enzymatic activity and mRNA level by vitamin E in rat blood cells.

PubMed

Hajiani, Maliheh; Razi, Farideh; Golestani, Aboualfazl; Frouzandeh, Mehdi; Owji, Ali Akbar; Khaghani, Shahnaz; Ghannadian, Naghmeh; Shariftabrizi, Ahmad; Pasalar, Parvin

2012-01-01

Vitamin E is the most important lipid-soluble antioxidant. Recently, it has been proposed as a gene regulator, and its gene modulation effects have been observed at different levels of gene expression and cell signaling. This study was performed to investigate the effects of vitamin E on the activity and expression of the most important endogenous antioxidant enzyme, superoxide dismutase (SOD), in rat plasma. Twenty-eight male Sprauge-Dawley rats were divided into four groups: control group and three dosing groups. The control group received the vehicle (liquid paraffin), and the dosing groups received twice-weekly intraperitoneal injections of 10, 30, and 100 mg/kg of vitamin E ((±)-α-Tocopherol) for 6 weeks. Quantitative real-time reverse transcription-polymerase chain reaction and enzyme assays were used to assess the levels of Cu/Zn-SOD and Mn-SOD mRNA and enzyme activity levels in blood cells at 0, 2, 4, and 6 weeks following vitamin E administration. Catalase enzyme activity and total antioxidant capacity were also assessed in plasma at the same time intervals. Mn-SOD activity was significantly increased in the 100 and 30 mg/kg dosing groups after 4 and 6 weeks, with corresponding significant increase in their mRNA levels. Cu/Zn-SOD activity was not significantly changed in response to vitamin E administration at any time points, whereas Cu/Zn-SOD mRNA levels were significantly increased after longer time points with high doses (30 and 100 mg/kg) of vitamin E. Catalase enzyme activity was transiently but significantly increased after 4 weeks of vitamin E treatment in 30 and 100 mg/kg dosing groups. Total antioxidant status was significantly increased after 4 and 6 weeks in the 100 mg/kg dosing group. Only the chronic administration of higher doses of alpha-tocopherol is associated with the increased activity and expression of Mn-SOD in rats. Cu/Zn-SOD activity and expression does not dramatically change in response to vitamin E.

X-chromosome-counting mechanisms that determine nematode sex.

PubMed

Nicoll, M; Akerib, C C; Meyer, B J

1997-07-10

Sex is determined in Caenorhabditis elegans by an X-chromosome-counting mechanism that reliably distinguishes the twofold difference in X-chromosome dose between males (1X) and hermaphrodites (2X). This small quantitative difference is translated into the 'on/off' response of the target gene, xol-1, a switch that specifies the male fate when active and the hermaphrodite fate when inactive. Specific regions of X contain counted signal elements whose combined dose sets the activity of xol-1. Here we ascribe the dose effects of one region to a discrete, protein-encoding gene, fox-1. We demonstrate that the dose-sensitive signal elements on chromosome X control xol-1 through two different molecular mechanisms. One involves the transcriptional repression of xol-1 in XX animals. The other uses the putative RNA-binding protein encoded by fox-1 to reduce the level of xol-1 protein. These two mechanisms of repression act together to ensure the fidelity of the X-chromosome counting process.

Gene expression analysis indicates CB1 receptor upregulation in the hippocampus and neurotoxic effects in the frontal cortex 3 weeks after single-dose MDMA administration in Dark Agouti rats

PubMed Central

2013-01-01

Background 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is a widely used recreational drug known to impair cognitive functions on the long-run. Both hippocampal and frontal cortical regions have well established roles in behavior, memory formation and other cognitive tasks and damage of these regions is associated with altered behavior and cognitive functions, impairments frequently described in heavy MDMA users. The aim of this study was to examine the hippocampus, frontal cortex and dorsal raphe of Dark Agouti rats with gene expression arrays (Illumina RatRef bead arrays) looking for possible mechanisms and new candidates contributing to the effects of a single dose of MDMA (15 mg/kg) 3 weeks earlier. Results The number of differentially expressed genes in the hippocampus, frontal cortex and the dorsal raphe were 481, 155, and 15, respectively. Gene set enrichment analysis of the microarray data revealed reduced expression of 'memory’ and 'cognition’, 'dendrite development’ and 'regulation of synaptic plasticity’ gene sets in the hippocampus, parallel to the upregulation of the CB1 cannabinoid- and Epha4, Epha5, Epha6 ephrin receptors. Downregulated gene sets in the frontal cortex were related to protein synthesis, chromatin organization, transmembrane transport processes, while 'dendrite development’, 'regulation of synaptic plasticity’ and 'positive regulation of synapse assembly’ gene sets were upregulated. Changes in the dorsal raphe region were mild and in most cases not significant. Conclusion The present data raise the possibility of new synapse formation/synaptic reorganization in the frontal cortex three weeks after a single neurotoxic dose of MDMA. In contrast, a prolonged depression of new neurite formation in the hippocampus is suggested by the data, which underlines the particular vulnerability of this brain region after the drug treatment. Finally, our results also suggest the substantial contribution of CB1 receptor and endocannabinoid mediated pathways in the hippocampal impairments. Taken together the present study provides evidence for the participation of new molecular candidates in the long-term effects of MDMA. PMID:24378229

Extrapolation of the dna fragment-size distribution after high-dose irradiation to predict effects at low doses

NASA Technical Reports Server (NTRS)

Ponomarev, A. L.; Cucinotta, F. A.; Sachs, R. K.; Brenner, D. J.; Peterson, L. E.

2001-01-01

The patterns of DSBs induced in the genome are different for sparsely and densely ionizing radiations: In the former case, the patterns are well described by a random-breakage model; in the latter, a more sophisticated tool is needed. We used a Monte Carlo algorithm with a random-walk geometry of chromatin, and a track structure defined by the radial distribution of energy deposition from an incident ion, to fit the PFGE data for fragment-size distribution after high-dose irradiation. These fits determined the unknown parameters of the model, enabling the extrapolation of data for high-dose irradiation to the low doses that are relevant for NASA space radiation research. The randomly-located-clusters formalism was used to speed the simulations. It was shown that only one adjustable parameter, Q, the track efficiency parameter, was necessary to predict DNA fragment sizes for wide ranges of doses. This parameter was determined for a variety of radiations and LETs and was used to predict the DSB patterns at the HPRT locus of the human X chromosome after low-dose irradiation. It was found that high-LET radiation would be more likely than low-LET radiation to induce additional DSBs within the HPRT gene if this gene already contained one DSB.

The combined effects of vinclozolin and procymidone do not deviate from expected additivity in vitro and in vivo.

PubMed

Nellemann, Christine; Dalgaard, Majken; Lam, Henrik Rye; Vinggaard, Anne Marie

2003-02-01

The combination effects of the well-known antiandrogenic fungicides, vinclozolin and procymidone, were tested both in vitro and in vivo. In vitro both vinclozolin and procymidone significantly inhibited the binding of agonist to the androgen receptor with the concentration that resulted in 50% inhibition (IC(50)) values of 0.1 and 0.6 micro M, respectively. By applying the isobole method, the effect of combining the two pesticides in vitro was found to be additive. In castrated testosterone-treated rats the administration of vinclozolin starting at 10 mg/kg led to a decrease in organ weight of all tested reproductive organs. The levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were increased significantly with doses of 100 mg/kg vinclozolin and above. Expression of the androgen-responsive gene, TRPM-2, was increased starting at 100 mg/kg vinclozolin. For procymidone, reproductive organ weights were diminished at 10 mg/kg and LH was increased at a concentration of 25 mg/kg and above, compared to the testosterone-treated controls. FSH was significantly increased only at 25 mg/kg procymidone. The studied gene expressions were changed by 100 mg/kg procymidone. Dosing the animals with a combination of a 1:1 mixture of vinclozolin and procymidone resulted in a weight reduction in the reproductive organs and an increase of serum LH and FSH as early as with 10 mg/kg combined dose. The relative expressions of TRPM-2 and PBP C3 were changed compared to controls at 100 mg/kg. The level of 5-HT in the rat brain was increased after a dose of 10 mg/kg. Using the isobole method, comparisons of the observed and predicted effects assuming additivity on reproductive organ weights, hormone levels, and gene expression showed agreement and thus the combination effects are suggested to be additive in vivo as well as in vitro.

The effect of high-dose vitamin D supplementation on muscular function and quality of life in postmenopausal women-A randomized controlled trial.

PubMed

Grimnes, G; Emaus, N; Cashman, K D; Jorde, R

2017-07-01

Observational studies have suggested positive associations between serum 25-hydroxyvitamin D (25(OH)D) levels and muscular strength, balance and quality of life. Our aim was to examine whether high-dose vitamin D supplementation would improve these measures as compared to standard-dose vitamin D, as well as the possible muscular effects of single nucleotide polymorphisms (SNPs) in genes encoding vitamin D-related enzymes. A 12-month randomized, double-blind, controlled trial where the participants received daily elemental calcium (1000 mg) plus vitamin D 3 (800 IU). In addition, the participants were randomized to receive either capsules with vitamin D 3 (20 000 IU) or matching placebos to be taken twice a week. A total of 297 postmenopausal women with osteopenia or osteoporosis. Muscle strength (handgrip and knee extensor strength), balance (tandem test) and quality of life (EQ-5D) were measured at baseline and after 12 months. The subjects were genotyped for SNPs related to vitamin D metabolism. Of the 297 included women, 275 completed the study. Mean serum 25(OH)D levels dramatically increased in the high-dose group (from 64.7 to 164.1 nmol/L; P<.01), while a more moderate increased was observed in the standard-dose group (from 64.1 to 81.8 nmol/L; P<.01). There was no significant difference between the groups in change in muscular strength, balance or quality of life over the intervention period. Polymorphisms in rs3829251 (located in the 7-dehydrocholesterol reductase gene) were associated with muscle strength and treatment effects. One-year treatment with high-dose vitamin D had no effect on muscular strength, balance or quality of life in postmenopausal women with osteopenia or osteoporosis as compared to standard dose. The association between rs3829251 and muscle strength needs confirmation in other populations. © 2017 John Wiley & Sons Ltd.

Suppression of adenoviral gene expression in the liver: role of innate vs adaptive immunity and their cell lysis mechanisms.

PubMed

Minagawa, Masahiro; Kawamura, Hiroki; Liu, Zhangxu; Govindarajan, Sugantha; Dennert, Gunther

2005-06-01

Injection of adenoviral constructs causes liver infection prompting immunity, which suppress viral gene expression. Innate and adaptive immunity mediate these processes raising the question which pathways are the most prominent. Adenovirus expressing the beta-galactosidase (beta-gal) gene was injected into normal and immunodeficient mice. Elimination of beta-gal-expressing hepatocytes and increases in liver enzymes were assayed. Major histocompatibility complex (MHC) class I densities, perforin channel insertion and apoptosis by Fas and tumor necrosis factor (TNF)-alpha were assayed. At high virus doses, suppression of viral gene expression was as efficient in immunodeficient as in normal mice, while at low doses effects of cytotoxic T lymphocytes (CTL) were demonstrable. Despite CTL priming and elimination of infected hepatocytes no liver injury is detected. Hepatocyte MHC I densities were able to trigger CTL granule exocytosis and perforin lysis in vitro but not in vivo. This is we show is because of decreased sensitivity of hepatocytes from infected mice to perforin and increased sensitivity to Fas and TNF-alpha lysis. Effector cells of the innate immune system are exceedingly effective in suppressing adenoviral gene expression. Perforin-independent pathways, those mediated by TNF-alpha and Fas are very efficient in hepatocytes from virus-infected livers.

Pharmacogenetic analysis of opioid dependence treatment dose and dropout rate.

PubMed

Crist, Richard C; Li, James; Doyle, Glenn A; Gilbert, Alex; Dechairo, Bryan M; Berrettini, Wade H

2018-01-01

Currently, no pharmacogenetic tests for selecting an opioid-dependence pharmacotherapy have been approved by the US Food and Drug Administration. Determine the effects of variants in 11 genes on dropout rate and dose in patients receiving methadone or buprenorphine/naloxone (ClinicalTrials.gov Identifier: NCT00315341). Variants in six pharmacokinetic genes (CYP1A2, CYP2B6, CYP2C19, CYP2C9, CYP2D6, CYP3A4) and five pharmacodynamic genes (HTR2A, OPRM1, ADRA2A, COMT, SLC6A4) were genotyped in samples from a 24-week, randomized, open-label trial of methadone and buprenorphine/naloxone for the treatment of opioid dependence (n = 764; 68.7% male). Genotypes were then used to determine the metabolism phenotype for each pharmacokinetic gene. Phenotypes or genotypes for each gene were analyzed for association with dropout rate and mean dose. Genotype for 5-HTTLPR in the SLC6A4 gene was nominally associated with dropout rate when the methadone and buprenorphine/naloxone groups were combined. When the most significant variants associated with dropout rate were analyzed using pairwise analyses, SLC6A4 (5-HTTLPR) and COMT (Val158Met; rs4860) had nominally significant associations with dropout rate in methadone patients. None of the genes analyzed in the study was associated with mean dose of methadone or buprenorphine/naloxone. This study suggests that functional polymorphisms related to synaptic dopamine or serotonin levels may predict dropout rates during methadone treatment. Patients with the S/S genotype at 5-HTTLPR in SLC6A4 or the Val/Val genotype at Val158Met in COMT may require additional treatment to improve their chances of completing addiction treatment. Replication in other methadone patient populations will be necessary to ensure the validity of these findings.

NASA GeneLab Project: Bridging Space Radiation Omics with Ground Studies.

PubMed

Beheshti, Afshin; Miller, Jack; Kidane, Yared; Berrios, Daniel; Gebre, Samrawit G; Costes, Sylvain V

2018-06-01

Accurate assessment of risks of long-term space missions is critical for human space exploration. It is essential to have a detailed understanding of the biological effects on humans living and working in deep space. Ionizing radiation from galactic cosmic rays (GCR) is a major health risk factor for astronauts on extended missions outside the protective effects of the Earth's magnetic field. Currently, there are gaps in our knowledge of the health risks associated with chronic low-dose, low-dose-rate ionizing radiation, specifically ions associated with high (H) atomic number (Z) and energy (E). The NASA GeneLab project ( https://genelab.nasa.gov/ ) aims to provide a detailed library of omics datasets associated with biological samples exposed to HZE. The GeneLab Data System (GLDS) includes datasets from both spaceflight and ground-based studies, a majority of which involve exposure to ionizing radiation. In addition to detailed information on radiation exposure for ground-based studies, GeneLab is adding detailed, curated dosimetry information for spaceflight experiments. GeneLab is the first comprehensive omics database for space-related research from which an investigator can generate hypotheses to direct future experiments, utilizing both ground and space biological radiation data. The GLDS is continually expanding as omics-related data are generated by the space life sciences community. Here we provide a brief summary of the space radiation-related data available at GeneLab.

Qualitative and quantitative approaches in the dose-response assessment of genotoxic carcinogens.

PubMed

Fukushima, Shoji; Gi, Min; Kakehashi, Anna; Wanibuchi, Hideki; Matsumoto, Michiharu

2016-05-01

Qualitative and quantitative approaches are important issues in field of carcinogenic risk assessment of the genotoxic carcinogens. Herein, we provide quantitative data on low-dose hepatocarcinogenicity studies for three genotoxic hepatocarcinogens: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and N-nitrosodiethylamine (DEN). Hepatocarcinogenicity was examined by quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci, which are the preneoplastic lesions in rat hepatocarcinogenesis and the endpoint carcinogenic marker in the rat liver medium-term carcinogenicity bioassay. We also examined DNA damage and gene mutations which occurred through the initiation stage of carcinogenesis. For the establishment of points of departure (PoD) from which the cancer-related risk can be estimated, we analyzed the above events by quantitative no-observed-effect level and benchmark dose approaches. MeIQx at low doses induced formation of DNA-MeIQx adducts; somewhat higher doses caused elevation of 8-hydroxy-2'-deoxyquanosine levels; at still higher doses gene mutations occurred; and the highest dose induced formation of GST-P positive foci. These data indicate that early genotoxic events in the pathway to carcinogenesis showed the expected trend of lower PoDs for earlier events in the carcinogenic process. Similarly, only the highest dose of IQ caused an increase in the number of GST-P positive foci in the liver, while IQ-DNA adduct formation was observed with low doses. Moreover, treatment with DEN at low doses had no effect on development of GST-P positive foci in the liver. These data on PoDs for the markers contribute to understand whether genotoxic carcinogens have a threshold for their carcinogenicity. The most appropriate approach to use in low dose-response assessment must be approved on the basis of scientific judgment. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Dose-dependent Toxicity of Humanized Renilla reniformis GFP (hrGFP) Limits Its Utility as a Reporter Gene in Mouse Muscle.

PubMed

Wallace, Lindsay M; Moreo, Andrew; Clark, K Reed; Harper, Scott Q

2013-04-16

Gene therapy has historically focused on delivering protein-coding genes to target cells or tissues using a variety of vectors. In recent years, the field has expanded to include gene-silencing strategies involving delivery of noncoding inhibitory RNAs, such as short hairpin RNAs or microRNAs (miRNAs). Often called RNA interference (RNAi) triggers, these small inhibitory RNAs are difficult or impossible to visualize in living cells or tissues. To circumvent this detection problem and ensure efficient delivery in preclinical studies, vectors can be engineered to coexpress a fluorescent reporter gene to serve as a marker of transduction. In this study, we set out to optimize adeno-associated viral (AAV) vectors capable of delivering engineered miRNAs and green fluorescent protein (GFP) reporter genes to skeletal muscle. Although the more broadly utilized enhanced GFP (eGFP) gene derived from the jellyfish, Aequorea victoria was a conventional choice, we were concerned about some previous studies suggesting this protein was myotoxic. We thus opted to test vectors carrying the humanized Renilla reniformis-derived GFP (hrGFP) gene, which has not seen as extensive usage as eGFP but was purported to be a safer and less cytotoxic alternative. Employing AAV6 vector dosages typically used in preclinical gene transfer studies (3×10(10) -1 × 10(11) particles), we found that hrGFP caused dose-dependent myopathy when delivered to wild-type (wt) mouse muscle, whereas identical titers of AAV6 carrying eGFP were relatively benign. Dose de-escalation at or below 8 × 10(9) AAV particles effectively reduced or eliminated hrGFP-associated myotoxicity, but also had dampening effects on green fluorescence and miRNA-mediated gene silencing in whole muscles. We conclude that hrGFP is impractical for use as a transduction marker in preclinical, AAV-based RNA interference therapy studies where adult mouse muscle is the target organ. Moreover, our data support that eGFP is superior to hrGFP as a reporter gene in mouse muscle. These results may impact the design of future preclinical gene therapy studies targeting muscles and non-muscle tissues alike.Molecular Therapy - Nucleic Acids (2013) 2, e86; doi:10.1038/mtna.2013.16; published online 16 April 2013.

Differential gene expression responses distinguish contact and respiratory sensitizers and nonsensitizing irritants in the local lymph node assay.

PubMed

Adenuga, David; Woolhiser, Michael R; Gollapudi, B Bhaskar; Boverhof, Darrell R

2012-04-01

Genomic approaches have the potential to enhance the specificity and predictive accuracy of existing toxicology endpoints, including those for chemical sensitization. The present study was conducted to determine whether gene expression responses can distinguish contact sensitizers (1-chloro-2,4-dinitrobenzene [DNCB] and hexyl cinnamic aldehyde [HCA]), respiratory sensitizers (ortho-phthalaldehyde and trimellitic anhydride [TMA]), and nonsensitizing irritants (methyl salicylate [MS] and nonanoic acid [NA]) in the local lymph node assay (LLNA). Female Balb/c mice received doses of each chemical as per the standard LLNA dosing regimen on days 1, 2, and 3. Auricular lymph nodes were analyzed for tritiated thymidine ((3)HTdR) incorporation on day 6 and for gene expression responses on days 6 and 10. All chemicals induced dose-dependent increases in stimulation index, which correlated strongly with the number of differentially expressed genes. A majority of genes modulated by the irritants were similarly altered by the sensitizers, consistent with the irritating effects of the sensitizers. However, a select number of responses involved with immune-specific functions, such as dendritic cell activation, were unique to the sensitizers and may offer the ability to distinguish sensitizers from irritants. Genes for the mast cell proteases 1 and 8, Lgals7, Tim2, Aicda, Il4, and Akr1c18 were more strongly regulated by respiratory sensitizers compared with contact sensitizers and may represent potential biomarkers for discriminating between contact and respiratory sensitizers. Collectively, these data suggest that gene expression responses may serve as useful biomarkers to distinguish between respiratory and contact sensitizers and nonsensitizing irritants in the LLNA.

Dose additive effects of simvastatin and dipentyl phthalate on ...

EPA Pesticide Factsheets

Sex differentiation of the mammalian reproductive tract is a highly regulated process that is driven, in part, by fetal testosterone (T) production. In utero exposure to phthalate esters (PE) during sex differentiation can cause reproductive tract malformations in rats. PE alter the expression of genes associated with steroid synthesis/transport and cholesterol biosynthesis. Simvastatin (SMV) is a cholesterol-lowering drug that inhibits HMG-CoA reductase. As cholesterol is a precursor for steroid biosynthesis, we proposed that maternal exposure to SMV during the critical period of sex differentiation would lower fetal T and result in corresponding alterations in cholesterol- and androgenmediated gene expression. Timed pregnant SD rats were dosed orally with SMV from GD14-GD18. T production on GD18 was measured by RIA, and changes in gene expression in maternal and fetal tissues were assessed by quantitative rt-PCR. Circulating lipids were also measured in dams and fetuses. SMV lowered fetal T production, altered several genes involved in cholesterol biosynthesis in the maternal liver, and lowered lipids in the fetus but not in the dam. Unlike PE, SMV did not alter genes associated with sex differentiation. In a second experiment, dams were dosed with SMV, dipentyl phthalate (DPeP, a PE), or both. SMV and DPeP alone reduced fetal T production to 44.3 and 37.5% of control values, respectively, but the mixture reduced T production to 19.9% of control. These studies

Recommended approaches in the application of ...

EPA Pesticide Factsheets

ABSTRACT:Only a fraction of chemicals in commerce have been fully assessed for their potential hazards to human health due to difficulties involved in conventional regulatory tests. It has recently been proposed that quantitative transcriptomic data can be used to determine benchmark dose (BMD) and estimate a point of departure (POD). Several studies have shown that transcriptional PODs correlate with PODs derived from analysis of pathological changes, but there is no consensus on how the genes that are used to derive a transcriptional POD should be selected. Because of very large number of unrelated genes in gene expression data, the process of selecting subsets of informative genes is a major challenge. We used published microarray data from studies on rats exposed orally to multiple doses of six chemicals for 5, 14, 28, and 90 days. We evaluated eight different approaches to select genes for POD derivation and compared them to three previously proposed approaches. The relationship between transcriptional BMDs derived using these 11 approaches were compared with PODs derived from apical data that might be used in a human health risk assessment. We found that transcriptional benchmark dose values for all 11 approaches were remarkably aligned with different apical PODs, while a subset of between 3 and 8 of the approaches met standard statistical criteria across the 5-, 14-, 28-, and 90-day time points and thus qualify as effective estimates of apical PODs. Our r

Genome-wide association study of therapeutic opioid dosing identifies a novel locus upstream of OPRM1

PubMed Central

Smith, Andrew H.; Jensen, Kevin P.; Li, Jin; Nunez, Yaira; Farrer, Lindsay A.; Hakonarson, Hakon; Cook-Sather, Scott D.; Kranzler, Henry R.; Gelernter, Joel

2017-01-01

Opioids are very effective analgesics, but they are also highly addictive. Methadone is used to treat opioid dependence (OD), acting as a selective agonist at the μ-opioid receptor encoded by the gene OPRM1. Determining the optimal methadone maintenance dose is time-consuming; currently, no biomarkers are available to guide treatment. In methadone-treated OD subjects drawn from a case and control sample, we conducted a genome-wide association study (GWAS) of usual daily methadone dose. In African-American (AA) OD subjects (n = 383), we identified a genome-wide significant association between therapeutic methadone dose (mean = 68.0 mg, standard deviation (SD) = 30.1 mg) and rs73568641 (P = 2.8 × 10−8), the nearest gene (306 kilobases) being OPRM1. Each minor (C) allele corresponded to an additional ~20 mg/day of oral methadone, an effect specific to AAs. In European-Americans (EAs) (n = 1,027), no genome-wide significant associations with methadone dose (mean = 77.8 mg, SD = 33.9 mg) were observed. In an independent set of opioid-naïve AA children being treated for surgical pain, rs73568641-C was associated with a higher required dose of morphine (n = 241, P = 3.9 × 10−2). Similarly, independent genomic loci previously shown to associate with higher opioid analgesic dose were associated with higher methadone dose in the OD sample (AA and EA: n = 1,410, genetic score P = 1.3 × 10−3). The present results in AAs indicate that genetic variants influencing opioid sensitivity across different clinical settings could contribute to precision pharmacotherapy for pain and addiction. PMID:28115739

Developmental and genetic toxicity of stannous chloride in mouse dams and fetuses.

PubMed

El-Makawy, Aida I; Girgis, Shenouda M; Khalil, Wagdy K B

2008-12-08

Humans are exposed to stannous chloride (SnCl2) present in packaged food, soft drinks, biocides, dentifrices, etc. Health effects in children exposed to tin and tin compounds have not been investigated yet. Therefore, we evaluated the possible teratogenic and genotoxic effects of SnCl2 in pregnant female mice and their fetuses. Teratogenic effects including morphological malformation of the fetus and its skeleton were observed. Exposures to environmental stressors including toxic chemicals that have the potential of modulating the immune system can often be linked to ecologically relevant endpoints, such as reduced resistance to disease. Therefore, the semi-quantitative reverse-transcription PCR (RT-PCR) assay was used to evaluate the expression of immune-response genes in the liver of SnCl2-treated dams and their fetuses. Bone-marrow cells of dams and fetuses were investigated for the presence of aberrant chromosomes. Three oral doses of SnCl2 (2, 10 and 20 mg/kg bw) were tested. The results of the teratological study show that SnCl2 induced a significant decrease in the number of living fetuses and a significant increase in the number of post-implantation losses. The high dose of SnCl2 induced complete post-implantation loss. Furthermore, SnCl2 caused reduction in the ossification of the fetal skeleton. The RT-PCR assay showed that the immune-response genes GARP and SIMP were not expressed in the liver of dams and fetuses in the controls or in the group treated with SnCl2 at 2 mg/kg bw. However, the expression of these genes was up-regulated in the groups treated with the other doses of SnCl2. Regarding the chromosome analysis, SnCl2 induced a dose-dependent increase in the frequency of individual and total chromosomal aberrations (P

Inclusion of dosimetric data as covariates in toxicity-related radiogenomic studies : A systematic review.

PubMed

Yahya, Noorazrul; Chua, Xin-Jane; Manan, Hanani A; Ismail, Fuad

2018-05-17

This systematic review evaluates the completeness of dosimetric features and their inclusion as covariates in genetic-toxicity association studies. Original research studies associating genetic features and normal tissue complications following radiotherapy were identified from PubMed. The use of dosimetric data was determined by mining the statement of prescription dose, dose fractionation, target volume selection or arrangement and dose distribution. The consideration of the dosimetric data as covariates was based on the statement mentioned in the statistical analysis section. The significance of these covariates was extracted from the results section. Descriptive analyses were performed to determine their completeness and inclusion as covariates. A total of 174 studies were found to satisfy the inclusion criteria. Studies published ≥2010 showed increased use of dose distribution information (p = 0.07). 33% of studies did not include any dose features in the analysis of gene-toxicity associations. Only 29% included dose distribution features as covariates and reported the results. 59% of studies which included dose distribution features found significant associations to toxicity. A large proportion of studies on the correlation of genetic markers with radiotherapy-related side effects considered no dosimetric parameters. Significance of dose distribution features was found in more than half of the studies including these features, emphasizing their importance. Completeness of radiation-specific clinical data may have increased in recent years which may improve gene-toxicity association studies.

Molecular and Histopathological Changes in Mouse Intestinal Tissue After Proton Exposure

NASA Technical Reports Server (NTRS)

Purgason, Ashley; Wu, Honglu

2010-01-01

Whole body exposure to protons in mice causes significant apoptosis in the crypts of the small intestine. Increasing numbers of crypts contained more apoptotic lesions as the dose of exposure increased. 16 genes associated with apoptotic pathways were shown to have significantly altered expression as compared to control samples for at least one of the doses of proton exposure 1 gene, Trp53inp1, was significantly up-regulated across all three doses. Those animals exposed to 0.1 Gy of proton irradiation showed greater amounts of significant alterations in gene expression as compared to 1 Gy and 2 Gy exposures. The differences in gene expression changes of low and high dose proton irradiated mice may offer insight into the molecular mechanisms of the possible high sensitivity at low proton doses. RAIDD (CRADD) may be responsible for the hypersensitivity observed in the duodenum of mice exposed to low doses of protons. Caspase-1 may also play a role in the hypersensitivity seen following proton irradiation at a dose of 0.1 Gy. FOXO3A may be involved in the down-regulation of GILZ observed at high doses of proton exposure.

Impact of Low Dose Oral Exposure to Bisphenol A (BPA) on the Neonatal Rat Hypothalamic and Hippocampal Transcriptome: A CLARITY-BPA Consortium Study

PubMed Central

Arambula, Sheryl E.; Belcher, Scott M.; Planchart, Antonio; Turner, Stephen D.

2016-01-01

Bisphenol A (BPA) is an endocrine disrupting, high volume production chemical found in a variety of products. Evidence of prenatal exposure has raised concerns that developmental BPA may disrupt sex-specific brain organization and, consequently, induce lasting changes on neurophysiology and behavior. We and others have shown that exposure to BPA at doses below the no-observed-adverse-effect level can disrupt the sex-specific expression of estrogen-responsive genes in the neonatal rat brain including estrogen receptors (ERs). The present studies, conducted as part of the Consortium Linking Academic and Regulatory Insights of BPA Toxicity program, expanded this work by examining the hippocampal and hypothalamic transcriptome on postnatal day 1 with the hypothesis that genes sensitive to estrogen and/or sexually dimorphic in expression would be altered by prenatal BPA exposure. NCTR Sprague-Dawley dams were gavaged from gestational day 6 until parturition with BPA (0-, 2.5-, 25-, 250-, 2500-, or 25 000-μg/kg body weight [bw]/d). Ethinyl estradiol was used as a reference estrogen (0.05- or 0.5-μg/kg bw/d). Postnatal day 1 brains were microdissected and gene expression was assessed with RNA-sequencing (0-, 2.5-, and 2500-μg/kg bw BPA groups only) and/or quantitative real-time PCR (all exposure groups). BPA-related transcriptional changes were mainly confined to the hypothalamus. Consistent with prior observations, BPA induced sex-specific effects on hypothalamic ERα and ERβ (Esr1 and Esr2) expression and hippocampal and hypothalamic oxytocin (Oxt) expression. These data demonstrate prenatal BPA exposure, even at doses below the current no-observed-adverse-effect level, can alter gene expression in the developing brain. PMID:27571134

Impact of Low Dose Oral Exposure to Bisphenol A (BPA) on the Neonatal Rat Hypothalamic and Hippocampal Transcriptome: A CLARITY-BPA Consortium Study.

PubMed

Arambula, Sheryl E; Belcher, Scott M; Planchart, Antonio; Turner, Stephen D; Patisaul, Heather B

2016-10-01

Bisphenol A (BPA) is an endocrine disrupting, high volume production chemical found in a variety of products. Evidence of prenatal exposure has raised concerns that developmental BPA may disrupt sex-specific brain organization and, consequently, induce lasting changes on neurophysiology and behavior. We and others have shown that exposure to BPA at doses below the no-observed-adverse-effect level can disrupt the sex-specific expression of estrogen-responsive genes in the neonatal rat brain including estrogen receptors (ERs). The present studies, conducted as part of the Consortium Linking Academic and Regulatory Insights of BPA Toxicity program, expanded this work by examining the hippocampal and hypothalamic transcriptome on postnatal day 1 with the hypothesis that genes sensitive to estrogen and/or sexually dimorphic in expression would be altered by prenatal BPA exposure. NCTR Sprague-Dawley dams were gavaged from gestational day 6 until parturition with BPA (0-, 2.5-, 25-, 250-, 2500-, or 25 000-μg/kg body weight [bw]/d). Ethinyl estradiol was used as a reference estrogen (0.05- or 0.5-μg/kg bw/d). Postnatal day 1 brains were microdissected and gene expression was assessed with RNA-sequencing (0-, 2.5-, and 2500-μg/kg bw BPA groups only) and/or quantitative real-time PCR (all exposure groups). BPA-related transcriptional changes were mainly confined to the hypothalamus. Consistent with prior observations, BPA induced sex-specific effects on hypothalamic ERα and ERβ (Esr1 and Esr2) expression and hippocampal and hypothalamic oxytocin (Oxt) expression. These data demonstrate prenatal BPA exposure, even at doses below the current no-observed-adverse-effect level, can alter gene expression in the developing brain.

Hepatitis C virus dynamics and cellular gene expression in uPA-SCID chimeric mice with humanized livers during intravenous silibinin monotherapy

DOE PAGES

DebRoy, Swati; Hiraga, Nobuhiko; Imamura, Michio; ...

2016-06-08

Legalon SIL (SIL) is a chemically hydrophilized version of silibinin, an extract of milk thistle ( Silybum marianum) seeds that has exhibited hepatoprotective and antiviral effectiveness against hepatitis C virus (HCV) in patients leading to viral clearance in combination with ribavirin. In this paper, to elucidate the incompletely understood mode of action of SIL against HCV, mathematical modelling of HCV kinetics and human hepatocyte gene expression studies were performed in uPA-SCID-chimeric mice with humanized livers. Chronically HCV-infected mice (n = 15) were treated for 14 days with daily intravenous SIL at 469, 265 or 61.5 mg/kg. Serum HCV and humanmore » albumin (hAlb) were measured frequently, and liver HCV RNA was analysed at days 3 and 14. Microarray analysis of human hepatocyte gene expression was performed at days 0, 3 and 14 of treatment. While hAlb remained constant, a biphasic viral decline in serum was observed consisting of a rapid 1st phase followed by a second slower phase (or plateau with the two lower SIL dosings). SIL effectiveness in blocking viral production was similar among dosing groups (median ε = 77%). However, the rate of HCV-infected hepatocyte decline, δ, was dose-dependent. Intracellular HCV RNA levels correlated (r = 0.66, P = 0.01) with serum HCV RNA. Pathway analysis revealed increased anti-inflammatory and antiproliferative gene expression in human hepatocytes in SIL-treated mice. Finally, the results suggest that SIL could lead to a continuous second-phase viral decline, that is potentially viral clearance, in the absence of adaptive immune response along with increased anti-inflammatory and antiproliferative gene expression in human hepatocytes.« less

Hepatitis C virus dynamics and cellular gene expression in uPA-SCID chimeric mice with humanized livers during intravenous silibinin monotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

DebRoy, Swati; Hiraga, Nobuhiko; Imamura, Michio

Legalon SIL (SIL) is a chemically hydrophilized version of silibinin, an extract of milk thistle ( Silybum marianum) seeds that has exhibited hepatoprotective and antiviral effectiveness against hepatitis C virus (HCV) in patients leading to viral clearance in combination with ribavirin. In this paper, to elucidate the incompletely understood mode of action of SIL against HCV, mathematical modelling of HCV kinetics and human hepatocyte gene expression studies were performed in uPA-SCID-chimeric mice with humanized livers. Chronically HCV-infected mice (n = 15) were treated for 14 days with daily intravenous SIL at 469, 265 or 61.5 mg/kg. Serum HCV and humanmore » albumin (hAlb) were measured frequently, and liver HCV RNA was analysed at days 3 and 14. Microarray analysis of human hepatocyte gene expression was performed at days 0, 3 and 14 of treatment. While hAlb remained constant, a biphasic viral decline in serum was observed consisting of a rapid 1st phase followed by a second slower phase (or plateau with the two lower SIL dosings). SIL effectiveness in blocking viral production was similar among dosing groups (median ε = 77%). However, the rate of HCV-infected hepatocyte decline, δ, was dose-dependent. Intracellular HCV RNA levels correlated (r = 0.66, P = 0.01) with serum HCV RNA. Pathway analysis revealed increased anti-inflammatory and antiproliferative gene expression in human hepatocytes in SIL-treated mice. Finally, the results suggest that SIL could lead to a continuous second-phase viral decline, that is potentially viral clearance, in the absence of adaptive immune response along with increased anti-inflammatory and antiproliferative gene expression in human hepatocytes.« less

[Effect of the Industrial Nanoparticles TiO 2 , SiO 2 and ZnO on Cell Viability and Gene Expression in Red Bone Marrow of Mus Musculus].

PubMed

Zarria-Romero, Jacquelyne; Osorio, Ana; Pino, José; Shiga, Betty; Vivas-Ruiz, Dan

2017-01-01

To evaluate the effect of ZnO, TiO2 and SiO2 nanoparticles on cell viability and expression of the interleukin 7, interleukin 3, and granulocyte-macrophage colony stimulating factor (GM-CSF) genes in Mus musculus. Red bone marrow was extracted from five Balb/c mice for the analysis of cell viability using the MTT test. The mice were divided into two groups of five each: one group was inoculated intraperitoneally with 0.5, 1.0, 2.5, 5.0, and 10 mg/kg of ZnO and SiO2 nanoparticles, respectively, and the other group was inoculated with 5.0, 10.0, 15.0, 20.0, and 25 mg/kg of TiO2 nanoparticles, respectively. Thirty hours later, RNA was extracted from the red bone marrow of the mice in both groups for gene expression analysis using quantitative PCR and RT-PCR. ZnO and SiO2 nanoparticles reduced cell viability in a dose-dependent manner by 37% and 26%, respectively, starting at a dose of 1 mg/kg. TiO2 nanoparticles at 5 mg/kg and 10 mg/kg reduced the gene expression of interleukins 7 and 3 by 55.3% and 70.2%, respectively, and SiO2 nanoparticles caused the greatest decrease (91%) in the expression of GM-CSF. ZnO nanoparticles reduced the expression of GM-CSF starting at doses of 20 mg/kg and 25 mg/kg. ZnO, SiO2 and TiO2 nanoparticles affect cell viability and gene expression in the mouse bone marrow.

Organ-specific effects of low-dose zinc pre-exposure on high-dose zinc induced mitochondrial dysfunction in large yellow croaker Pseudosciaena crocea.

PubMed

Zheng, Jia-Lang; Yuan, Shuang-Shuang; Shen, Bin; Wu, Chang-Wen

2017-04-01

The study was carried out to evaluate the effects of low-dose zinc (Zn) pre-exposure on survival rate, new Zn accumulation, and mitochondrial bioenergetics in the liver and spleen of large yellow croaker exposed to high-dose Zn. To the end, fish were pre-exposed to 0 and 2 mg L -1 Zn for 48 h and post-exposed to 0 and 12 mg L -1 Zn for 48 h. Twelve milligrams Zn per liter exposure alone reduced survival rate, but the effect did not appear in the 2 mg L -1 Zn pre-exposure groups. Two milligrams per liter Zn pre-exposure also ameliorated 12 mg Zn L -1 induced new Zn accumulation, reactive oxygen species (ROS) levels, and mitochondrial swelling in the liver. However, these effects did not appear in the spleen. In the liver, 2 mg L -1 Zn pre-exposure apparently relieved 12 mg L -1 Zn induced down-regulation of activities of ATP synthase (F-ATPase), succinate dehydrogenase (SDH), and malate dehydrogenase (MDH). The mRNA levels of these genes remained relatively stable in fish exposed to 12 mg L -1 Zn alone, but increased in fish exposed to 12 mg L -1 Zn with 2 mg L -1 Zn pre-treatment. In the spleen, 2 mg Zn L -1 pre-exposure did not mitigate the down-regulation of mRNA levels of genes and activities of relative enzymes induced by 12 mg L -1 Zn. In conclusion, our study demonstrated low-dose zinc pre-exposure ameliorated high-dose zinc induced mitochondrial dysfunction in the liver but not in the spleen of large yellow croaker, indicating an organ-specific effect.

“Stealth” Adenoviruses Blunt Cell-Mediated and Humoral Immune Responses against the Virus and Allow for Significant Gene Expression upon Readministration in the Lung

PubMed Central

Croyle, Maria A.; Chirmule, Narendra; Zhang, Yi; Wilson, James M.

2001-01-01

Most of the early gene therapy trials for cystic fibrosis have been with adenovirus vectors. First-generation viruses with E1a and E1b deleted are limited by transient expression of the transgene and substantial inflammatory responses. Gene transfer is also significantly curtailed following a second dose of virus. In an effort to reduce adenovirus-associated inflammation, capsids of first-generation vectors were modified with various activated monomethoxypolyethylene glycols. Cytotoxic T-lymphocyte production was significantly reduced in C57BL/6 mice after a single intratracheal administration of modified vectors, and length of gene expression was extended from 4 to 42 days. T-cell subsets from mice exposed to the conjugated vectors demonstrated a marked decrease in Th1 responses and slight enhancement of Th2 responses compared to animals dosed with native virus. Neutralizing antibodies (NAB) against adenovirus capsid proteins were reduced in serum and bronchoalveolar lavage fluid of animals after a single dose of modified virus, allowing significant levels of gene expression upon rechallenge with native adenovirus. Modification with polyethylene glycol (PEG) also allowed substantial gene expression from the new vectors in animals previously immunized with unmodified virus. However, gene expression was significantly reduced after two doses of the same PEG-conjugated vector. Alternating the activation group of PEG between doses did produce significant gene expression upon readministration. This technology in combination with second-generation or helper-dependent adenovirus could produce dosing strategies which promote successful readministration of vector in clinical trials and marked expression in patients with significant anti-adenovirus NAB levels and reduce the possibility of immune reactions against viral vectors for gene therapy. PMID:11312351

Exposure to low UVA doses increases KatA and KatB catalase activities, and confers cross-protection against subsequent oxidative injuries in Pseudomonas aeruginosa.

PubMed

Pezzoni, Magdalena; Tribelli, Paula M; Pizarro, Ramón A; López, Nancy I; Costa, Cristina S

2016-05-01

Solar UVA radiation is one of the main environmental stress factors for Pseudomonas aeruginosa. Exposure to high UVA doses produces lethal effects by the action of the reactive oxygen species (ROS) it generates. P. aeruginosa has several enzymes, including KatA and KatB catalases, which provide detoxification of ROS. We have previously demonstrated that KatA is essential in defending P. aeruginosa against high UVA doses. In order to analyse the mechanisms involved in the adaptation of this micro-organism to UVA, we investigated the effect of exposure to low UVA doses on KatA and KatB activities, and the physiological consequences. Exposure to UVA induced total catalase activity; assays with non-denaturing polyacrylamide gels showed that both KatA and KatB activities were increased by radiation. This regulation occurred at the transcriptional level and depended, at least partly, on the increase in H2O2 levels. We demonstrated that exposure to low UVA produced a protective effect against subsequent lethal doses of UVA, sodium hypochlorite and H2O2. Protection against lethal UVA depends on katA, whilst protection against sodium hypochlorite depends on katB, demonstrating that different mechanisms are involved in the defence against these oxidative agents, although both genes can be involved in the global cellular response. Conversely, protection against lethal doses of H2O2 could depend on induction of both genes and/or (an)other defensive factor(s). A better understanding of the adaptive response of P. aeruginosa to UVA is relevant from an ecological standpoint and for improving disinfection strategies that employ UVA or solar irradiation.

Effects of repeated potassium iodide administration on genes involved in synthesis and secretion of thyroid hormone in adult male rat.

PubMed

Lebsir, Dalila; Manens, Line; Grison, Stephane; Lestaevel, Philippe; Ebrahimian, Teni; Suhard, David; Phan, Guillaume; Dublineau, Isabelle; Tack, Karine; Benderitter, Marc; Pech, Annick; Jourdain, Jean-Rene; Souidi, Maâmar

2018-02-26

A single dose of potassium iodide (KI) is recommended to reduce the risk of thyroid cancer during nuclear accidents. However in case of prolonged radioiodine exposure, more than one dose of KI may be necessary. This work aims to evaluate the potential toxic effect of repeated administration of KI. Adult Wistar rats received an optimal dose of KI 1 mg/kg over a period of 1, 4 or 8 days. hormonal status (TSH, FT4) of treated rats was unaffected. Contrariwise, a sequential Wolff-Chaikoff effect was observed, resulting in a prompt decrease of NIS and MCT8 mRNA expression (-58% and -26% respectively), followed by a delayed decrease of TPO mRNA expression (-33%) in conjunction with a stimulation of PDS mRNA expression (+62%). we show for the first time that repeated administration of KI at 1 mg/kg/24h doesn't cause modification of thyroid hormones level, but leads to a reversible modification of the expression of genes involved in the synthesis and secretion of thyroid hormones. Copyright © 2018 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ambrosone, Alfredo; Scotto di Vettimo, Maria Rosaria; Malvindi, Maria Ada

It is generally accepted that silica (SiO{sub 2}) is not toxic. But the increasing use of silica nanoparticles (SiO{sub 2}NPs) in many different industrial fields has prompted the careful investigation of their toxicity in biological systems. In this report, we describe the effects elicited by SiO{sub 2}NPs on animal and cell physiology. Stable and monodisperse amorphous silica nanoparticles, 25 nM in diameter, were administered to living Hydra vulgaris (Cnidaria). The dose-related effects were defined by morphological and behavioral assays. The results revealed an all-or-nothing lethal toxicity with a rather high threshold (35 nM NPs) and a LT50 of 38 h.more » At sub lethal doses, the morphophysiological effects included: animal morphology alterations, paralysis of the gastric region, disorganization and depletion of tentacle specialized cells, increase of apoptotic and collapsed cells, and reduction of the epithelial cell proliferation rate. Transcriptome analysis (RNAseq) revealed 45 differentially expressed genes, mostly involved in stress response and cuticle renovation. Our results show that Hydra reacts to SiO{sub 2}NPs, is able to rebalance the animal homeostasis up to a relatively high doses of SiO{sub 2}NPs, and that the physiological modifications are transduced to gene expression modulation.« less

Low-Dose Ionizing Radiation Exposure, Oxidative Stress and Epigenetic Programing of Health and Disease.

PubMed

Tharmalingam, Sujeenthar; Sreetharan, Shayenthiran; Kulesza, Adomas V; Boreham, Douglas R; Tai, T C

2017-10-01

Ionizing radiation exposure from medical diagnostic imaging has greatly increased over the last few decades. Approximately 80% of patients who undergo medical imaging are exposed to low-dose ionizing radiation (LDIR). Although there is widespread consensus regarding the harmful effects of high doses of radiation, the biological effects of low-linear energy transfer (LET) LDIR is not well understood. LDIR is known to promote oxidative stress, however, these levels may not be large enough to result in genomic mutations. There is emerging evidence that oxidative stress causes heritable modifications via epigenetic mechanisms (DNA methylation, histone modification, noncoding RNA regulation). These epigenetic modifications result in permanent cellular transformations without altering the underlying DNA nucleotide sequence. This review summarizes the major concepts in the field of epigenetics with a focus on the effects of low-LET LDIR (<100 mGy) and oxidative stress on epigenetic gene modification. In this review, we show evidence that suggests that LDIR-induced oxidative stress provides a mechanistic link between LDIR and epigenetic gene regulation. We also discuss the potential implication of LDIR exposure during pregnancy where intrauterine fetal development is highly susceptible to oxidative stress-induced epigenetic programing.

Gene expression profiling in rat kidney after intratracheal exposure to cadmium-doped nanoparticles

NASA Astrophysics Data System (ADS)

Coccini, Teresa; Roda, Elisa; Fabbri, Marco; Sacco, Maria Grazia; Gribaldo, Laura; Manzo, Luigi

2012-08-01

While nephrotoxicity of cadmium is well documented, very limited information exists on renal effects of exposure to cadmium-containing nanomaterials. In this work, "omics" methodologies have been used to assess the action of cadmium-containing silica nanoparticles (Cd-SiNPs) in the kidney of Sprague-Dawley rats exposed intratracheally. Groups of animals received a single dose of Cd-SiNPs (1 mg/rat), CdCl2 (400 μg/rat) or 0.1 ml saline (control). Renal gene expression was evaluated 7 and 30 days post exposure by DNA microarray technology using the Agilent Whole Rat Genome Microarray 4x44K. Gene modulating effects were observed in kidney at both time periods after treatment with Cd-SiNPs. The number of differentially expressed genes being 139 and 153 at the post exposure days 7 and 30, respectively. Renal gene expression changes were also observed in the kidney of CdCl2-treated rats with a total of 253 and 70 probes modulated at 7 and 30 days, respectively. Analysis of renal gene expression profiles at day 7 indicated in both Cd-SiNP and CdCl2 groups downregulation of several cluster genes linked to immune function, oxidative stress, and inflammation processes. Differing from day 7, the majority of cluster gene categories modified by nanoparticles in kidney 30 days after dosing were genes implicated in cell regulation and apoptosis. Modest renal gene expression changes were observed at day 30 in rats treated with CdCl2. These results indicate that kidney may be a susceptible target for subtle long-lasting molecular alterations produced by cadmium nanoparticles locally instilled in the lung.

Dynamics of wound healing signaling as a potential therapeutic target for radiation-induced tissue damage.

PubMed

Chung, Yih-Lin; Pui, Newman N M

2015-01-01

We hypothesized the histone deacetylase inhibitor phenylbutyrate (PB) has beneficial effects on radiation-induced injury by modulating the expression of DNA repair and wound healing genes. Hamsters received a radiosurgical dose of radiation (40 Gy) to the cheek and were treated with varying PB dosing regimens. Gross alteration of the irradiated cheeks, eating function, histological changes, and gene expression during the course of wound healing were compared between treatment groups. Pathological analysis showed decreased radiation-induced mucositis, facilitated epithelial cell growth, and preventing ulcerative wound formation, after short-term PB treatment, but not after vehicle or sustained PB. The radiation-induced wound healing gene expression profile exhibited a sequential transition from the inflammatory and DNA repair phases to the tissue remodeling phase in the vehicle group. Sustained PB treatment resulted in a prolonged wound healing gene expression profile and delayed the wound healing process. Short-term PB shortened the duration of inflammatory cytokine expression, triggered repeated pulsed expression of cell cycle and DNA repair-regulating genes, and promoted earlier oscillatory expression of tissue remodeling genes. Distinct gene expression patterns between sustained and short-term treatment suggest dynamic profiling of wound healing gene expression can be an important part of a biological therapeutic strategy to mitigate radiation-related tissue injury. © 2015 by the Wound Healing Society.

ZIKA-001: Safety and Immunogenicity of an Engineered DNA Vaccine Against ZIKA virus infection

PubMed Central

Tebas, Pablo; Roberts, Christine C; Muthumani, Kar; Reuschel, Emma; White, Scott; Khan, Amir S; Racine, Trina; Choi, Hyeree; Zaidi, Faraz; Boyer, Jean; Kudchodkar, Sagar; Park, Young K; Trottier, Sylvie; Remigio, Celine; Krieger, Diane; Kobinger, Gary P; Weiner, David; Maslow, Joel

2017-01-01

Abstract Background While Zika virus (ZIKV) infection is typically self-limited, congenital birth defects and Guillain-Barré syndrome are well-described. There are no therapies or vaccines against ZIKV infection. Methods ZIKA-001 is a phase I, open label, clinical trial designed to evaluate the safety, side effect profile, and immunogenicity of a synthetic, DNA vaccine (GLS-5700) targeting the pre-membrane+envelope proteins (prME) of the virus. Two groups of 20 participants received GLS-5700 at one of two dose levels: 1 mg or 2 mg DNA/dose at 0, 4, and 12 weeks. Vaccine was administered as 0.1 or 0.2 ml (1 or 2 mg) intradermal (ID) injection followed by electroporation (EP) with the CELLECTRA®-3P device Results The median age of the 40 participants was 38 (IQR 30–54) years; 60% were female 30% Latino and 78% white. No SAEs have been reported to date. Local minor AEs were injection site pain, redness, swelling and itching that occurred in half of the participants. Systemic adverse events were rare and included headache, myalgias, upper respiratory infections, fatigue/malaise and nausea. Four weeks after the first dose 25% vs. 60% of the participants in the 1 mg and 2 mg dose seroconverted. By week 6, 2 weeks after the second dose, the response was 65 and 84% respectively and 2 weeks after the third dose all participants in both dosing groups developed antibodies. At the end of the vaccination period over 60% of vaccinated person neutralized Zika virus in a vero cell assay and greater than 80% on neuronal cell targets. The protective efficacy of the antibodies generated by the vaccine was evaluated in the lethal IFNAR−/− mouse model. After the intraperitoneal administration of 0.1 ml of either baseline, week 14 serum or PBS the animals were challenged with 106 PFUs of ZIKV PR209 isolate. Whereas animals administered PBS (control) or baseline serum succumbed after a median of 5 days, those pretreated with week 14 serum from study participants survived suggesting that the humoral response generated by the vaccine is protective in this model. Conclusion Our trial shows for the first time in humans the safety and immunogenicity of an engineered DNA encoding consensus viral protein against ZIKV. Future studies will evaluate the effectiveness of the vaccine. Disclosures C. C. Roberts, GeneOne: Member, Salary. S. White, GeneOne: Member, Salary. A. S. Khan, Inovio: Employee and Shareholder, Salary and Stock. J. Boyer, Inovio: Employee and Shareholder, Salary and Stock. Y. K. Park, GeneOne: Board Member, CEO and Employee, Salary and Stock. S. Trottier, Canadian Institutes of Health Research: Investigator, Research grant. C. Remigio, GeneOne: Employee and Shareholder, Salary and Stock. G. P. Kobinger, GeneOne: Grant Investigator and Scientific Advisor, Grant recipient and Research support. D. Weiner, GeneOne: Grant Investigator and Scientific Advisor, Grant recipient, Licensing agreement or royalty and Stock. J. Maslow, GeneOne: Employee, Salary and Stock.

Exposition of humans to low doses and low dose rate irradiation: an urgent need for new markers and new models.

PubMed

Chenal, C; Legue, F; Nourgalieva, K; Brouazin-Jousseaume, V; Durel, S; Guitton, N

2000-01-01

In human radiation protection, the shape of the dose effects curve for low doses irradiation (LDI) is assumed to be linear, extrapolated from the clinical consequences of Hiroshima and Nagasaki nuclear explosions. This extrapolation probably overestimates the risk below 200 mSv. In many circumstances, the living species and cells can develop some mechanisms of adaptation. Classical epidemiological studies will not be able to answer the question and there is a need to assess more sensitive biological markers of the effects of LDI. The researches should be focused on DNA effects (strand breaks), radioinduced expression of new genes and proteins involved in the response to oxidative stress and DNA repair mechanisms. New experimental biomolecular techniques should be developed in parallel with more conventional ones. Such studies would permit to assess new biological markers of radiosensitivity, which could be of great interest in radiation protection and radio-oncology.

Genotoxic effects of vinclozolin on the aquatic insect Chironomus riparius (Diptera, Chironomidae).

PubMed

Aquilino, Mónica; Sánchez-Argüello, Paloma; Martínez-Guitarte, José-Luis

2018-01-01

Vinclozolin (Vz) is a pollutant found in aquatic environments whose antiandrogenic effects in reproduction are well known in mammals. Although its reproductive effects have been less studied in invertebrates, other effects, including genotoxicity, have been described. Therefore, in this work, we studied the genotoxic effects of Vz in the freshwater benthic invertebrate Chironomus riparius. DNA damage was evaluated with the comet assay (tail area, olive moment, tail moment and % DNA in tail), and the transcriptional levels of different genes involved in DNA repair (ATM, NLK and XRCC1) and apoptosis (DECAY) were measured by RT-PCR. Fourth instar larvae of C. riparius, were exposed to Vz for 24 h at 20 and 200 μg/L. The Vz exposures affected the DNA integrity in this organism, since a dose-response relationship occurred, with DNA strand breaks significantly increased with increased dose for tail area, olive moment and tail moment parameters. Additionally, the lower concentration of Vz produced a significant induction of the transcripts of three genes under study (ATM, NLK and XRCC1) showing the activation of the cellular repair mechanism. In contrast, the expression of these genes with the highest concentration were downregulated, indicating failure of the cellular repair mechanism, which would explain the higher DNA damage. These data report for the first time the alterations of Vz on gene transcription of an insect and confirm the potential genotoxicity of this compound on freshwater invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of space relevant radiation exposure on differentiation and mineralization of murine osteoprogenitor cells

NASA Astrophysics Data System (ADS)

Lau, Patrick; Hu, Yueyuan; Hellweg, Christine; Baumstark-Khan, Christa; Reitz, Guenther

Extended exposure to altered gravity conditions like during long-term space flight results in significant bone loss. Exposure to ionizing radiation for cancer therapy causes bone damage and may increase the risk of fractures. Similarly, besides altered gravity conditions, astronauts on exploratory missions beyond low-Earth orbit will be exposed to high-energy heavy ions in addition to proton and photon radiation, although for prolonged periods and at lower doses and dose rates compared with therapy. Space conditions may place astronauts at a greater risk for mission-critical fractures. Until now, little is known about the effects of space radiation on the skeletal system especially on osteoprogenitor cells. Accelerator facilities are used to simulate parts of the radiation environment in space. Heavy ion accelerators therefore could be used to assess radiation risks for astronauts who will be exposed to higher radiation doses e.g. on a Mars mission. The aim of the present study was to determine the biological effects of spaceflight-relevant radiation exposure on the cellular level using murine osteoprogenitor cell lines compared to nonirradiated controls. To gain a deeper understanding of bone cell differenti-ation and mineralization after exposure to heavy ions, we examined gene expression modulation of bone specific transcription factors, osteoblast specific marker genes as well as genes function as coupling factors that link bone resorption to bone formation. We investigated the transcrip-tional modulation of type I collagen (Col I), osteocalcin (Ocn), Transforming growth factor-β1 (TGF-β1), interleukin-6 (IL-6) and the bone specific transcription factor Runx2 (Cbfa1). To gain deeper insight into potential cellular mechanisms involved in cellular response after ex-posure to heavy ions, we investigated gene expression modulations after exposure to energetic carbon ions (35 MeV/u, 73.2 keV/µm), iron ions (1000 MeV/u, 150 keV/µm) and lead ions (29 MeV/u, 9600 keV/µm) versus low LET X-rays. Exposure to X-irradiation dose-dependently increased the mRNA levels of Runx2 (cbfa1) whereas expression values of OCN and TGF-β1 were elevated at later time points. Exposure to heavy ions provoked a more marked effect on bone specific gene expression within the differentiation process. Collectively, our results indi-cate that heavy ions facilitate differentiation more effectively than X-rays as a major response in the progeny of irradiated osteoprogenitor cells. The data presented allow us to suggest that exposure to ionizing radiation interferes with bone formation at the level of cellular differenti-ation. In this regard, further experiments are needed to investigate gene expression patterns in mammalian cells that respond to differentiation after exposure to ionizing radiation.

PREVALENCE OF COMBINATORIAL CYP2C9 AND VKORC1 GENOTYPES IN PUERTO RICANS: IMPLICATIONS FOR WARFARIN MANAGEMENT IN HISPANICS

PubMed Central

Duconge, Jorge; Cadilla, Carmen L.; Windemuth, Andreas; Kocherla, Mohan; Gorowski, Krystyna; Seip, Richard L.; Bogaard, Kali; Renta, Jessica Y.; Piovanetti, Paola; D’Agostino, Darrin; Santiago-Borrero, Pedro J.; Ruaño, Gualberto

2010-01-01

Polymorphisms in the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) genes significantly alter the effective warfarin dose. We determined the frequencies of alleles, single carriers, and double carriers of single nucleotide polymorphisms (SNPs) in the CYP2C9 and VKORC1 genes in a Puerto Rican cohort and gauged the impact of these polymorphisms on warfarin dosage using a published algorithm. A total of 92 DNA samples were genotyped using Luminex® x-MAP technology. The polymorphism frequencies were 6.52%, 5.43% and 28.8% for CYP2C9 *2, *3 and VKORC1-1639 G>A polymorphisms, respectively. The prevalence of combinatorial genotypes was 16% for carriers of both the CYP2C9 and VKORC1 polymorphisms, 9% for carriers of CYP2C9 polymorphisms, 35% for carriers of the VKORC1 polymorphism, and the remaining 40% were non-carriers for either gene. Based on a published warfarin dosing algorithm, single, double and triple carriers of functionally deficient polymorphisms predict reductions of 1.0–1.6, 2.0–2.9, and 2.9–3.7 mg/day, respectively, in warfarin dose. Overall, 60% of the population carried at least a single polymorphism predicting deficient warfarin metabolism or responsiveness and 13% were double carriers with polymorphisms in both genes studied. Combinatorial genotyping of CYP2C9 and VKORC1 can allow for individualized dosing of warfarin among patients with gene polymorphisms, potentially reducing the risk of stroke or bleeding. PMID:20073138

Caffeine inhibits STAT1 signaling and downregulates inflammatory pathways involved in autoimmunity.

PubMed

Iris, Merve; Tsou, Pei-Suen; Sawalha, Amr H

2018-04-18

Caffeine is a widely consumed pharmacologically active product. We focused on characterizing immunomodulatory effects of caffeine on peripheral blood mononuclear cells. Caffeine at high doses showed a robust downregulatory effect on cytokine activity and genes related to several autoimmune diseases including lupus and rheumatoid arthritis. Dose-dependent validation experiments showed downregulation at the mRNA levels of key inflammation-related genes including STAT1, TNF, IFNG, and PPARG. TNF and PPARG were suppressed even with the lowest caffeine dose tested, which corresponds to the serum concentration of caffeine after administration of one cup of coffee. Cytokine levels of IL-8, MIP-1β, IL-6, IFN-γ, GM-CSF, TNF, IL-2, IL-4, MCP-1, and IL-10 were decreased significantly with caffeine treatment. Upstream regulator analysis suggests that caffeine inhibits STAT1 signaling, which was confirmed by showing reduced phosphorylated STAT1 after caffeine treatment. Further studies exploring disease-modulating potential of caffeine in autoimmune diseases and further exploring the mechanisms involved are warranted. Copyright © 2018 Elsevier Inc. All rights reserved.

Excretion of Antibiotic Resistance Genes by Dairy Calves Fed Milk Replacers with Varying Doses of Antibiotics

PubMed Central

Thames, Callie H.; Pruden, Amy; James, Robert E.; Ray, Partha P.; Knowlton, Katharine F.

2012-01-01

Elevated levels of antibiotic resistance genes (ARGs) in soil and water have been linked to livestock farms and in some cases feed antibiotics may select for antibiotic resistant gut microbiota. The purpose of this study was to examine the establishment of ARGs in the feces of calves receiving milk replacer containing no antibiotics versus subtherapeutic or therapeutic doses of tetracycline and neomycin. The effect of antibiotics on calf health was also of interest. Twenty-eight male and female dairy calves were assigned to one of the three antibiotic treatment groups at birth and fecal samples were collected at weeks 6, 7 (prior to weaning), and 12 (5 weeks after weaning). ARGs corresponding to the tetracycline (tetC, tetG, tetO, tetW, and tetX), macrolide (ermB, ermF), and sulfonamide (sul1, sul2) classes of antibiotics along with the class I integron gene, intI1, were monitored by quantitative polymerase chain reaction as potential indicators of direct selection, co-selection, or horizontal gene transfer of ARGs. Surprisingly, there was no significant effect of antibiotic treatment on the absolute abundance (gene copies per gram wet manure) of any of the ARGs except ermF, which was lower in the antibiotic-treated calf manure, presumably because a significant portion of host bacterial cells carrying ermF were not resistant to tetracycline or neomycin. However, relative abundance (gene copies normalized to 16S rRNA genes) of tetO was higher in calves fed the highest dose of antibiotic than in the other treatments. All genes, except tetC and intI1, were detectable in feces from 6 weeks onward, and tetW and tetG significantly increased (P < 0.10), even in control calves. Overall, the results provide new insight into the colonization of calf gut flora with ARGs in the early weeks. Although feed antibiotics exerted little effect on the ARGs monitored in this study, the fact that they also provided no health benefit suggests that the greater than conventional nutritional intake applied in this study overrides previously reported health benefits of antibiotics. The results suggest potential benefit of broader management strategies, and that cost and risk may be avoided by minimizing incorporation of antibiotics in milk replacer. PMID:22514550

Effect of delta sleep-inducing peptide on the expression of antioxidant enzyme genes in the brain and blood of rats during physiological aging.

PubMed

Kutilin, D S; Bondarenko, T I; Kornienko, I V; Mikhaleva, I I

2014-09-01

Subcutaneous injections of exogenous delta sleep-inducing peptide in a dose of 100 μg/kg (monthly, 5-day courses) to rats of various age groups (2-24 months) were followed by an increase in the expression of genes for SOD 1 (Sod1) and glutathione peroxidase 1 (Gpx1) in the brain and nucleated blood cells. The expression of these genes was shown to decrease during physiological aging of the body.

Analyzing the dose-dependence of the Saccharomyces cerevisiae global transcriptional response to methyl methanesulfonate and ionizing radiation.

PubMed

Benton, Michael G; Somasundaram, Swetha; Glasner, Jeremy D; Palecek, Sean P

2006-12-01

One of the most crucial tasks for a cell to ensure its long term survival is preserving the integrity of its genetic heritage via maintenance of DNA structure and sequence. While the DNA damage response in the yeast Saccharomyces cerevisiae, a model eukaryotic organism, has been extensively studied, much remains to be elucidated about how the organism senses and responds to different types and doses of DNA damage. We have measured the global transcriptional response of S. cerevisiae to multiple doses of two representative DNA damaging agents, methyl methanesulfonate (MMS) and gamma radiation. Hierarchical clustering of genes with a statistically significant change in transcription illustrated the differences in the cellular responses to MMS and gamma radiation. Overall, MMS produced a larger transcriptional response than gamma radiation, and many of the genes modulated in response to MMS are involved in protein and translational regulation. Several clusters of coregulated genes whose responses varied with DNA damaging agent dose were identified. Perhaps the most interesting cluster contained four genes exhibiting biphasic induction in response to MMS dose. All of the genes (DUN1, RNR2, RNR4, and HUG1) are involved in the Mec1p kinase pathway known to respond to MMS, presumably due to stalled DNA replication forks. The biphasic responses of these genes suggest that the pathway is induced at lower levels as MMS dose increases. The genes in this cluster with a threefold or greater transcriptional response to gamma radiation all showed an increased induction with increasing gamma radiation dosage. Analyzing genome-wide transcriptional changes to multiple doses of external stresses enabled the identification of cellular responses that are modulated by magnitude of the stress, providing insights into how a cell deals with genotoxicity.

Iodine-131 dose-dependent gene expression: alterations in both normal and tumour thyroid tissues of post-Chernobyl thyroid cancers.

PubMed

Abend, M; Pfeiffer, R M; Ruf, C; Hatch, M; Bogdanova, T I; Tronko, M D; Hartmann, J; Meineke, V; Mabuchi, K; Brenner, A V

2013-10-15

A strong, consistent association between childhood irradiation and subsequent thyroid cancer provides an excellent model for studying radiation carcinogenesis. We evaluated gene expression in 63 paired RNA specimens from frozen normal and tumour thyroid tissues with individual iodine-131 (I-131) doses (0.008-8.6 Gy, no unirradiated controls) received from Chernobyl fallout during childhood (Ukrainian-American cohort). Approximately half of these randomly selected samples (32 tumour/normal tissue RNA specimens) were hybridised on 64 whole-genome microarrays (Agilent, 4 × 44 K). Associations between I-131 dose and gene expression were assessed separately in normal and tumour tissues using Kruskal-Wallis and linear trend tests. Of 155 genes significantly associated with I-131 after Bonferroni correction and with ≥2-fold increase per dose category, we selected 95 genes. On the remaining 31 RNA samples these genes were used for validation purposes using qRT-PCR. Expression of eight genes (ABCC3, C1orf9, C6orf62, FGFR1OP2, HEY2, NDOR1, STAT3, and UCP3) in normal tissue and six genes (ANKRD46, CD47, HNRNPH1, NDOR1, SCEL, and SERPINA1) in tumour tissue was significantly associated with I-131. PANTHER/DAVID pathway analyses demonstrated significant over-representation of genes coding for nucleic acid binding in normal and tumour tissues, and for p53, EGF, and FGF signalling pathways in tumour tissue. The multistep process of radiation carcinogenesis begins in histologically normal thyroid tissue and may involve dose-dependent gene expression changes.

p53 activated by AND gate genetic circuit under radiation and hypoxia for targeted cancer gene therapy.

PubMed

Ding, Miao; Li, Rong; He, Rong; Wang, Xingyong; Yi, Qijian; Wang, Weidong

2015-09-01

Radio-activated gene therapy has been developed as a novel therapeutic strategy against cancer; however, expression of therapeutic gene in peritumoral tissues will result in unacceptable toxicity to normal cells. To restrict gene expression in targeted tumor mass, we used hypoxia and radiation tolerance features of tumor cells to develop a synthetic AND gate genetic circuit through connecting radiation sensitivity promoter cArG6 , heat shock response elements SNF1, HSF1 and HSE4 with retroviral vector plxsn. Their construction and dynamic activity process were identified through downstream enhanced green fluorescent protein and wtp53 expression in non-small cell lung cancer A549 cells and in a nude mice model. The result showed that AND gate genetic circuit could be activated by lower required radiation dose (6 Gy) and after activated, AND gate could induce significant apoptosis effects and growth inhibition of cancer cells in vitro and in vivo. The radiation- and hypoxia-activated AND gate genetic circuit, which could lead to more powerful target tumoricidal activity represented a promising strategy for both targeted and effective gene therapy of human lung adenocarcinoma and low dose activation character of the AND gate genetic circuit implied that this model could be further exploited to decrease side-effects of clinical radiation therapy. © 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Long-term treatment with green tea polyphenols modifies the gut microbiome of female sprague-dawley rats.

PubMed

Wang, Jincheng; Tang, Lili; Zhou, Hongyuan; Zhou, Jun; Glenn, Travis C; Shen, Chwan-Li; Wang, Jia-Sheng

2018-06-01

Green tea polyphenols (GTP) have been shown to exert a spectrum of health benefits to animals and humans. It is plausible that the beneficial effects of GTP are a result of its interaction with the gut microbiota. This study evaluated the effect of long-term treatment with GTP on the gut microbiota of experimental rats and the potential linkage between changes of the gut microbiota with the beneficial effects of GTP. Six-month-old Sprague-Dawley rats were randomly allocated into three dosing regimens (0, 0.5%, and 1.5% of GTP) and followed for 6 months. At the end of month 3 or month 6, half of the animals from each group were sacrificed and their colon contents were collected for microbiome analysis using 16S ribosomal RNA and shotgun metagenomic community sequencing. GTP treatment significantly decreased the biodiversity and modified the microbial community in a dose-dependent manner; similar patterns were observed at both sampling times. Multiple operational taxonomic units and phylotypes were modified: the phylotypes Bacteroidetes and Oscillospira, previously linked to the lean phenotype in human and animal studies, were enriched; and Peptostreptococcaceae previously linked to colorectal cancer phenotype was depleted in GTP treated groups in a dose-dependent manner. Several microbial gene orthologs were modified, among which genes related to energy production and conversion were consistently enriched in samples from month 6 in a dose-dependent manner. This study showed that long-term treatment with GTP induced a dose-dependent modification of the gut microbiome in experimental rats, which might be linked to beneficial effects of GTP. Copyright © 2018 Elsevier Inc. All rights reserved.

Left ventricular wall stress and sarcoplasmic reticulum Ca(2+)-ATPase gene expression in renal hypertensive rats: dose-dependent effects of ACE inhibition and AT1-receptor blockade.

PubMed

Zierhut, W; Studer, R; Laurent, D; Kästner, S; Allegrini, P; Whitebread, S; Cumin, F; Baum, H P; de Gasparo, M; Drexler, H

1996-05-01

Cardiac hypertrophy is associated with altered Ca2+ handling and may predispose to the development of LV dysfunction and cardiac failure. At the cellular level, the re-expression of ANF represents a well-established marker of myocyte hypertrophy while the decreased expression of the sarcoplasmatic reticulum (SR) Ca(2+)-ATPase is thought o play a crucial role in the alterations of Ca2+ handling and LV function. We assessed the dose-dependent effect of chronic ACE inhibition or AT1 receptor blockade on cardiac function in relation to the cardiac expression of the SR Ca(2+)-ATPase and ANF. Renal hypertensive rats (2K-1C) were treated for 12 weeks with three different doses of the ACE inhibitor benazepril, the AT1-receptor antagonist valsartan (each drug 0.3, 3, and 10 mg/kg per day i.p.) or placebo. LV dimensions, hypertrophy and wall stress were determined in vivo by magnetic resonance imaging and the gene expressions of ANF and SR Ca(2+)-ATPase were quantified by Northern blot. Low doses of both drugs did not affect blood pressure, hypertrophy, systolic wall stress and the ANF and SR Ca(2+)-ATPase gene expression. High doses of each drug reduced systolic blood pressure, wall stress, and LV hypertrophy to a similar extent and to values comparable to normotensive, age-matched rats. In addition, high dose treatment reduced LV end-systolic and end-diastolic volume as compared to untreated 2K-1C animals and normalized the mRNA levels of both ANF and SR Ca(2+)-ATPase (as compared to normotensive animals). We conclude that in this model, high doses of ACE inhibition and AT1-receptor blockade are necessary to normalize systolic blood pressure, LV hypertrophy and systolic LV wall stress which, in turn, is associated with restoration of a normal cardiac phenotype with respect to SR Ca(2+)-ATPase and ANF and normalization of cardiac function.

Biological impact of low dose-rate simulated solar particle event radiation in vivo.

PubMed

Chang, P Y; Doppalapudi, R; Bakke, J; Wang, A; Menda, S; Davis, Z

2010-08-01

C57Bl6-lacZ animals were exposed to a range of low dose-rate simulated solar particle event (sSPE) radiation at the NASA-sponsored Research Laboratory (NSRL) at Brookhaven National Laboratory (BNL). Peripheral blood was harvested from animals from 1 to 12 days after total body irradiation (TBI) to quantify the level of circulating reticulocytes (RET) and micronucleated reticulocytes (MN-RET) as an early indicator of radiation-induced genotoxicity. Bone marrow lymphocytes and hippocampal tissues from each animal were collected at 12 days and up to two months, to evaluate dose-dependent late effects after sSPE exposure. Early hematopoietic changes show that the % RET was reduced up to 3 days in response to radiation exposure but recovered at 12 days postirradiation. The % MN-RET in peripheral blood was temporally regulated and dependant on the total accumulated dose. Total chromosome aberrations in lymphocytes increased linearly with dose within a week after radiation and remained significantly higher than the control values at 4 weeks after exposure. The level of aberrations in the irradiated animals returned to control levels by 8 weeks postirradiation. Measurements of chromosome 2 and 8 specific aberrations indicate that, consistent with conventional giemsa-staining methods, the level of aberrations is also not significantly higher than in control animals at 8 weeks postirradiation. The hippocampus was surveyed for differential transcriptional regulation of genes known to be associated with neurogenesis. Our results showed differential expression of neurotrophin and their associated receptor genes within 1 week after sSPE exposure. Progressive changes in the profile of expressed genes known to be involved in neurogenic signaling pathways were dependent on the sSPE dose. Our results to date suggest that radiation-induced changes in the hematopoietic system, i.e., chromosome aberrations in lymphocytes, are transient and do not persist past 4 weeks after radiation. On the other hand, alteration in the profile of genes known to be involved in neurotrophic functions in the hippocampal tissue appears to persist for up to 8 weeks after radiation exposure. Such temporal changes confirm that, although cytogenetic changes after a single dose of low-dose and low-dose-rate protons appear to be transient, the impact of this exposure is sufficient to lead to persistent dynamic changes in neuronal tissues long after the initial radiation exposure.

Reactive oxygen species levels control NF-κB activation by low dose deferasirox in erythroid progenitors of low risk myelodysplastic syndromes.

PubMed

Meunier, Mathieu; Ancelet, Sarah; Lefebvre, Christine; Arnaud, Josiane; Garrel, Catherine; Pezet, Mylène; Wang, Yan; Faure, Patrice; Szymanski, Gautier; Duployez, Nicolas; Preudhomme, Claude; Biard, Denis; Polack, Benoit; Cahn, Jean-Yves; Moulis, Jean Marc; Park, Sophie

2017-12-01

Anemia is a frequent cytopenia in myelodysplastic syndromes (MDS) and most patients require red blood cell transfusion resulting in iron overload (IO). Deferasirox (DFX) has become the standard treatment of IO in MDS and it displays positive effects on erythropoiesis. In low risk MDS samples, mechanisms improving erythropoiesis after DFX treatment remain unclear. Herein, we addressed this question by using liquid cultures with iron overload of erythroid precursors treated with low dose of DFX (3μM), which corresponds to DFX 5 mg/kg/day, an unusual dose used for iron chelation. We highlight a decreased apoptosis rate and an increased proportion of cycling cells, both leading to higher proliferation rates. The iron chelation properties of low dose DFX failed to activate the Iron Regulatory Proteins and to support iron depletion, but low dose DFX dampers intracellular reactive oxygen species. Furthermore low concentrations of DFX activate the NF-κB pathway in erythroid precursors triggering anti-apoptotic and anti-inflammatory signals. Establishing stable gene silencing of the Thioredoxin (TRX) 1 genes, a NF-κB modulator, showed that fine-tuning of reactive oxygen species (ROS) levels regulates NF-κB. These results justify a clinical trial proposing low dose DFX in MDS patients refractory to erythropoiesis stimulating agents.

Reactive oxygen species levels control NF-κB activation by low dose deferasirox in erythroid progenitors of low risk myelodysplastic syndromes

PubMed Central

Meunier, Mathieu; Ancelet, Sarah; Lefebvre, Christine; Arnaud, Josiane; Garrel, Catherine; Pezet, Mylène; Wang, Yan; Faure, Patrice; Szymanski, Gautier; Duployez, Nicolas; Preudhomme, Claude; Biard, Denis; Polack, Benoit; Cahn, Jean-Yves; Moulis, Jean Marc; Park, Sophie

2017-01-01

Anemia is a frequent cytopenia in myelodysplastic syndromes (MDS) and most patients require red blood cell transfusion resulting in iron overload (IO). Deferasirox (DFX) has become the standard treatment of IO in MDS and it displays positive effects on erythropoiesis. In low risk MDS samples, mechanisms improving erythropoiesis after DFX treatment remain unclear. Herein, we addressed this question by using liquid cultures with iron overload of erythroid precursors treated with low dose of DFX (3μM), which corresponds to DFX 5 mg/kg/day, an unusual dose used for iron chelation. We highlight a decreased apoptosis rate and an increased proportion of cycling cells, both leading to higher proliferation rates. The iron chelation properties of low dose DFX failed to activate the Iron Regulatory Proteins and to support iron depletion, but low dose DFX dampers intracellular reactive oxygen species. Furthermore low concentrations of DFX activate the NF-κB pathway in erythroid precursors triggering anti-apoptotic and anti-inflammatory signals. Establishing stable gene silencing of the Thioredoxin (TRX) 1 genes, a NF-κB modulator, showed that fine-tuning of reactive oxygen species (ROS) levels regulates NF-κB. These results justify a clinical trial proposing low dose DFX in MDS patients refractory to erythropoiesis stimulating agents. PMID:29285268

Targeting the Epigenome with Bioactive Food Components for Cancer Prevention

PubMed Central

Ong, Thomas Prates; Moreno, Fernando Salvador; Ross, Sharon Ann

2012-01-01

Epigenetic processes participate in cancer development and likely influence cancer prevention. Global DNA hypomethylation, gene promoter hypermethylation and aberrant histone post-translational modifications are hallmarks of neoplastic cells which have been associated with genomic instability and altered gene expression. Because epigenetic deregulation occurs early in carcinogenesis and is potentially reversible, intervention strategies targeting the epigenome have been proposed for cancer prevention. Bioactive food components (BFCs) with anticancer potential, including folate, polyphenols, selenium, retinoids, fatty acids, isothiocyanates and allyl compounds, influence DNA methylation and histone modification processes. Such activities have been shown to affect the expression of genes involved in cell proliferation, death and differentiation that are frequently altered in cancer. Although the epigenome represents a promising target for cancer prevention with BFCs, few studies have addressed the influence of dietary components on these mechanisms in vivo, particularly on the phenotype of humans, and thus the exact mechanisms whereby diet mediates an effect on cancer prevention remains unclear. Primary factors that should be elucidated include the effective doses and dose timing of BFCs to attain epigenetic effects. Because diet-epigenome interactions are likely to occur in utero, the impact of early-life nutrition on cancer risk programming should be further investigated. PMID:22353664

Suppressive effects of chlorophyllin on mutagen-induced umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002) and tumor promoter-dependent ornithine decarboxylase induction in BALB/c 3T3 fibroblast cells.

PubMed

Okai, Y; Higashi-Okai, K; Yano, Y; Otani, S

1996-08-01

The potentially protective role of chlorophyllin, the sodium and copper salt of chlorophyll a against the initiation and promotion stages in carcinogenesis was studied by in vitro short-term assays. Chlorophyllin showed a dose-dependent suppressive effect on 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indol (Trp-P-1)-induced umu C gene expression of Salmonella typhimurium (TA 1535/pSK 1002) in the presence of metabolizing enzyme mixture. The similar inhibitory effect of chlorophyllin was detected in mitomycin C (MMC)-dependent umu C gene expression in the absence of metabolizing enzyme mixture. Furthermore chlorophyllin also exhibited a dose-dependent inhibition on 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced ornithine decarboxylase (ODC) activity of 3T3 fibroblast cells at the same concentrations. However, when chlorophyll a isolated from Japanese tea leaves was applied on the same assay systems as a comparative experiment, chlorophyll a showed much weaker activity compared with that of chlorophyllin. The significance of this finding is discussed from the viewpoint of the protective role of chlorophyllin against carcinogenesis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wyrobek, A. J.; Manohar, C. F.; Nelson, D. O.

We investigated the low dose dependency of the transcriptional response of human cells to characterize the shape and biological functions associated with the dose response curve and to identify common and conserved functions of low dose expressed genes across cells and tissues. Human lymphoblastoid (HL) cells from two unrelated individuals were exposed to graded doses of radiation spanning the range of 1-10 cGy were analyzed by transcriptome profiling, qPCR and bioinformatics, in comparison to sham irradiated samples. A set of {approx}80 genes showed consistent responses in both cell lines; these genes were associated with homeostasis mechanisms (e.g., membrane signaling, moleculemore » transport), subcellular locations (e.g., Golgi, and endoplasmic reticulum), and involved diverse signal transduction pathways. The majority of radiation-modulated genes had plateau-like responses across 1-10 cGy, some with suggestive evidence that transcription was modulated at doses below 1 cGy. MYC, FOS and TP53 were the major network nodes of the low-dose response in HL cells. Comparison our low dose expression findings in HL cells with those of prior studies in mouse brain after whole body exposure, in human keratinocyte cultures, and in endothelial cells cultures, indicates that certain components of the low dose radiation response are broadly conserved across cell types and tissues, independent of proliferation status.« less

Increased sensitivity to apoptosis induced by methotrexate is mediated by Jun N-terminal kinase

PubMed Central

Spurlock, Charles F.; Aune, Zachary T.; Tossberg, John T.; Collins, Patrick L.; Aune, Jessica P.; Huston, Joseph W.; Crooke, Philip S.; Olsen, Nancy J.; Aune, Thomas M.

2011-01-01

Objective Low-dose methotrexate [MTX] is an effective therapy for rheumatoid arthritis yet its mechanism of action is incompletely understood. Here, we explored induction of apoptosis by MTX. Methods We employed flow cytometry to assess changes in levels of intracellular proteins, reactive oxygen species [ROS], and apoptosis.Quantitative polymerase chain reaction was usedtoassess changes in transcript levels of select target genes in response to MTX. Results MTX does not directly induce apoptosis but rather ‘primes’ cells for markedly increased sensitivity to apoptosis via either mitochondrial or death receptor pathways by a Jun N-terminal kinase [JNK]-dependent mechanism. Increased sensitivity to apoptosis is mediated, at least in part, by MTX-dependent production of reactive oxygen species, JNK activation and JNK-dependent induction of genes whose protein products promote apoptosis. Supplementation with tetrahydrobiopterin blocks these methotrexate-induced effects. Subjects with rheumatoid arthritis on low-dose MTX therapy express elevated levels of the JNK-target gene, JUN. Conclusions Our results support a model whereby methotrexate inhibits reduction of dihydrobiopterin to tetrahydrobiopterin resulting in increased production of ROS, increased JNK activity and increased sensitivity to apoptosis. The finding of increased JUN levels in subjects with RA taking low-dose MTX supports the notion that this pathway is activated by MTX, in vivo, and may contribute to efficacy of MTX in inflammatory disease. PMID:21618198

Immunomodulatory effects of the Agaricus blazei Murrill-based mushroom extract AndoSan in patients with multiple myeloma undergoing high dose chemotherapy and autologous stem cell transplantation: a randomized, double blinded clinical study.

PubMed

Tangen, Jon-Magnus; Tierens, Anne; Caers, Jo; Binsfeld, Marilene; Olstad, Ole Kristoffer; Trøseid, Anne-Marie Siebke; Wang, Junbai; Tjønnfjord, Geir Erland; Hetland, Geir

2015-01-01

Forty patients with multiple myeloma scheduled to undergo high dose chemotherapy with autologous stem cell support were randomized in a double blinded fashion to receive adjuvant treatment with the mushroom extract AndoSan, containing 82% of Agaricus blazei Murrill (19 patients) or placebo (21 patients). Intake of the study product started on the day of stem cell mobilizing chemotherapy and continued until the end of aplasia after high dose chemotherapy, a period of about seven weeks. Thirty-three patients were evaluable for all study endpoints, while all 40 included patients were evaluable for survival endpoints. In the leukapheresis product harvested after stem cell mobilisation, increased percentages of Treg cells and plasmacytoid dendritic cells were found in patients receiving AndoSan. Also, in this group, a significant increase of serum levels of IL-1ra, IL-5, and IL-7 at the end of treatment was found. Whole genome microarray showed increased expression of immunoglobulin genes, Killer Immunoglobulin Receptor (KIR) genes, and HLA genes in the Agaricus group. Furthermore, AndoSan displayed a concentration dependent antiproliferative effect on mouse myeloma cells in vitro. There were no statistically significant differences in treatment response, overall survival, and time to new treatment. The study was registered with Clinicaltrials.gov NCT00970021.

Immunomodulatory Effects of the Agaricus blazei Murrill-Based Mushroom Extract AndoSan in Patients with Multiple Myeloma Undergoing High Dose Chemotherapy and Autologous Stem Cell Transplantation: A Randomized, Double Blinded Clinical Study

PubMed Central

Tierens, Anne; Caers, Jo; Binsfeld, Marilene; Olstad, Ole Kristoffer; Trøseid, Anne-Marie Siebke; Wang, Junbai; Tjønnfjord, Geir Erland; Hetland, Geir

2015-01-01

Forty patients with multiple myeloma scheduled to undergo high dose chemotherapy with autologous stem cell support were randomized in a double blinded fashion to receive adjuvant treatment with the mushroom extract AndoSan, containing 82% of Agaricus blazei Murrill (19 patients) or placebo (21 patients). Intake of the study product started on the day of stem cell mobilizing chemotherapy and continued until the end of aplasia after high dose chemotherapy, a period of about seven weeks. Thirty-three patients were evaluable for all study endpoints, while all 40 included patients were evaluable for survival endpoints. In the leukapheresis product harvested after stem cell mobilisation, increased percentages of Treg cells and plasmacytoid dendritic cells were found in patients receiving AndoSan. Also, in this group, a significant increase of serum levels of IL-1ra, IL-5, and IL-7 at the end of treatment was found. Whole genome microarray showed increased expression of immunoglobulin genes, Killer Immunoglobulin Receptor (KIR) genes, and HLA genes in the Agaricus group. Furthermore, AndoSan displayed a concentration dependent antiproliferative effect on mouse myeloma cells in vitro. There were no statistically significant differences in treatment response, overall survival, and time to new treatment. The study was registered with Clinicaltrials.gov NCT00970021. PMID:25664323

Metabolic Reprogramming by 3-Iodothyronamine (T1AM): A New Perspective to Reverse Obesity through Co-Regulation of Sirtuin 4 and 6 Expression.

PubMed

Assadi-Porter, Fariba M; Reiland, Hannah; Sabatini, Martina; Lorenzini, Leonardo; Carnicelli, Vittoria; Rogowski, Micheal; Selen Alpergin, Ebru S; Tonelli, Marco; Ghelardoni, Sandra; Saba, Alessandro; Zucchi, Riccardo; Chiellini, Grazia

2018-05-22

Obesity is a complex disease associated with environmental and genetic factors. 3-Iodothyronamine (T1AM) has revealed great potential as an effective weight loss drug. We used metabolomics and associated transcriptional gene and protein expression analysis to investigate the tissue specific metabolic reprogramming effects of subchronic T1AM treatment at two pharmacological daily doses (10 and 25 mg/kg) on targeted metabolic pathways. Multi-analytical results indicated that T1AM at 25 mg/kg can act as a novel master regulator of both glucose and lipid metabolism in mice through sirtuin-mediated pathways. In liver, we observed an increased gene and protein expression of Sirt6 (a master gene regulator of glucose) and Gck (glucose kinase) and a decreased expression of Sirt4 (a negative regulator of fatty acids oxidation (FAO)), whereas in white adipose tissue only Sirt6 was increased. Metabolomics analysis supported physiological changes at both doses with most increases in FAO, glycolysis indicators and the mitochondrial substrate, at the highest dose of T1AM. Together our results suggest that T1AM acts through sirtuin-mediated pathways to metabolically reprogram fatty acid and glucose metabolism possibly through small molecules signaling. Our novel mechanistic findings indicate that T1AM has a great potential as a drug for the treatment of obesity and possibly diabetes.

γ irradiation with different dose rates induces different DNA damage responses in Petunia x hybrida cells.

PubMed

Donà, Mattia; Ventura, Lorenzo; Macovei, Anca; Confalonieri, Massimo; Savio, Monica; Giovannini, Annalisa; Carbonera, Daniela; Balestrazzi, Alma

2013-05-15

In plants, there is evidence that different dose rate exposures to gamma (γ) rays can cause different biological effects. The dynamics of DNA damage accumulation and molecular mechanisms that regulate recovery from radiation injury as a function of dose rate are poorly explored. To highlight dose-rate dependent differences in DNA damage, single cell gel electrophoresis was carried out on regenerating Petunia x hybrida leaf discs exposed to LDR (total dose 50 Gy, delivered at 0.33 Gy min(-1)) and HDR (total doses 50 and 100 Gy, delivered at 5.15 Gy min(-1)) γ-ray in the 0-24h time period after treatments. Significant fluctuations of double strand breaks and different repair capacities were observed between treatments in the 0-4h time period following irradiation. Dose-rate-dependent changes in the expression of the PhMT2 and PhAPX genes encoding a type 2 metallothionein and the cytosolic isoform of ascorbate peroxidase, respectively, were detected by Quantitative RealTime-Polymerase Chain Reaction. The PhMT2 and PhAPX genes were significantly up-regulated (3.0- and 0.7-fold) in response to HDR. The results are discussed in light of the potential practical applications of LDR-based treatments in mutation breeding. Copyright © 2013 Elsevier GmbH. All rights reserved.

The Molecular Effect of Diagnostic Absorbed Doses from 131I on Papillary Thyroid Cancer Cells In Vitro.

PubMed

Stasiołek, Mariusz; Adamczewski, Zbigniew; Śliwka, Przemysław W; Puła, Bartosz; Karwowski, Bolesław; Merecz-Sadowska, Anna; Dedecjus, Marek; Lewiński, Andrzej

2017-06-15

Diagnostic whole-body scan is a standard procedure in patients with thyroid cancer prior to the application of a therapeutic dose of 131 I. Unfortunately, administration of the radioisotope in a diagnostic dose may decrease further radioiodine uptake-the phenomenon called "thyroid stunning". We estimated radiation absorbed dose-dependent changes in genetic material, in particular in the sodium iodide symporter (NIS) gene promoter, and the NIS protein level in a K1 cell line derived from the metastasis of a human papillary thyroid carcinoma exposed to 131 I in culture. The different activities applied were calculated to result in absorbed doses of 5, 10 and 20 Gy. Radioiodine did not affect the expression of the NIS gene at the mRNA level, however, we observed significant changes in the NIS protein level in K1 cells. The decrease of the NIS protein level observed in the cells subjected to the lowest absorbed dose was paralleled by a significant increase in 8-oxo-dG concentrations ( p < 0.01) and followed by late activation of the DNA repair pathways. Our findings suggest that the impact of 131 I radiation on thyroid cells, in the range compared to doses absorbed during diagnostic procedures, is not linear and depends on various factors including the cellular components of thyroid pathology.

Extreme sensitivity of gene expression in human SH-SY5Y neurocytes to ultra-low doses of Gelsemium sempervirens

PubMed Central

2014-01-01

Background Gelsemium sempervirens L. (Gelsemium s.) is a traditional medicinal plant, employed as an anxiolytic at ultra-low doses and animal models recently confirmed this activity. However the mechanisms by which it might operate on the nervous system are largely unknown. This work investigates the gene expression of a human neurocyte cell line treated with increasing dilutions of Gelsemium s. extract. Methods Starting from the crude extract, six 100 × (centesimal, c) dilutions of Gelsemium s. (2c, 3c, 4c, 5c, 9c and 30c) were prepared according to the French homeopathic pharmacopoeia. Human SH-SY5Y neuroblastoma cells were exposed for 24 h to test dilutions, and their transcriptome compared by microarray to that of cells treated with control vehicle solutions. Results Exposure to the Gelsemium s. 2c dilution (the highest dose employed, corresponding to a gelsemine concentration of 6.5 × 10-9 M) significantly changed the expression of 56 genes, of which 49 were down-regulated and 7 were overexpressed. Several of the down-regulated genes belonged to G-protein coupled receptor signaling pathways, calcium homeostasis, inflammatory response and neuropeptide receptors. Fisher exact test, applied to the group of 49 genes down-regulated by Gelsemium s. 2c, showed that the direction of effects was significantly maintained across the treatment with high homeopathic dilutions, even though the size of the differences was distributed in a small range. Conclusions The study shows that Gelsemium s., a medicinal plant used in traditional remedies and homeopathy, modulates a series of genes involved in neuronal function. A small, but statistically significant, response was detected even to very low doses/high dilutions (up to 30c), indicating that the human neurocyte genome is extremely sensitive to this regulation. PMID:24642002

Dose Calculations for [131I] Meta-Iodobenzylguanidine-Induced Bystander Effects

PubMed Central

Gow, M. D.; Seymour, C. B.; Boyd, M.; Mairs, R. J.; Prestiwch, W. V.; Mothersill, C. E.

2014-01-01

Targeted radiotherapy is a potentially useful treatment for some cancers and may be potentiated by bystander effects. However, without estimation of absorbed dose, it is difficult to compare the effects with conventional external radiation treatment. Methods: Using the Vynckier – Wambersie dose point kernel, a model for dose rate evaluation was created allowing for calculation of absorbed dose values to two cell lines transfected with the noradrenaline transporter (NAT) gene and treated with [131I]MIBG. Results: The mean doses required to decrease surviving fractions of UVW/NAT and EJ138/NAT cells, which received medium from [131I]MIBG-treated cells, to 25 – 30% were 1.6 and 1.7 Gy respectively. The maximum mean dose rates achieved during [131I]MIBG treatment were 0.09 – 0.75 Gy/h for UVW/NAT and 0.07 – 0.78 Gy/h for EJ138/NAT. These were significantly lower than the external beam gamma radiation dose rate of 15 Gy/h. In the case of control lines which were incapable of [131I]MIBG uptake the mean absorbed doses following radiopharmaceutical were 0.03 – 0.23 Gy for UVW and 0.03 – 0.32 Gy for EJ138. Conclusion: [131I]MIBG treatment for ICCM production elicited a bystander dose-response profile similar to that generated by external beam gamma irradiation but with significantly greater cell death. PMID:24659931

Gene therapy delivery systems for enhancing viral and nonviral vectors for cardiac diseases: current concepts and future applications.

PubMed

Katz, Michael G; Fargnoli, Anthony S; Williams, Richard D; Bridges, Charles R

2013-11-01

Gene therapy is one of the most promising fields for developing new treatments for the advanced stages of ischemic and monogenetic, particularly autosomal or X-linked recessive, cardiomyopathies. The remarkable ongoing efforts in advancing various targets have largely been inspired by the results that have been achieved in several notable gene therapy trials, such as the hemophilia B and Leber's congenital amaurosis. Rate-limiting problems preventing successful clinical application in the cardiac disease area, however, are primarily attributable to inefficient gene transfer, host responses, and the lack of sustainable therapeutic transgene expression. It is arguable that these problems are directly correlated with the choice of vector, dose level, and associated cardiac delivery approach as a whole treatment system. Essentially, a delicate balance exists in maximizing gene transfer required for efficacy while remaining within safety limits. Therefore, the development of safe, effective, and clinically applicable gene delivery techniques for selected nonviral and viral vectors will certainly be invaluable in obtaining future regulatory approvals. The choice of gene transfer vector, dose level, and the delivery system are likely to be critical determinants of therapeutic efficacy. It is here that the interactions between vector uptake and trafficking, delivery route means, and the host's physical limits must be considered synergistically for a successful treatment course.

LAURISTON S. TAYLOR LECTURE ON RADIATION PROTECTION AND MEASURMENTS: WHAT MAKES PARTICLE RADIATION SO EFFECTIVE?

PubMed Central

Blakely, Eleanor A.

2012-01-01

The scientific basis for the physical and biological effectiveness of particle radiations has emerged from many decades of meticulous basic research. A diverse array of biologically relevant consequences at the molecular, cellular, tissue, and organism level have been reported, but what are the key processes and mechanisms that make particle radiation so effective, and what competing processes define dose dependences? Recent studies have shown that individual genotypes control radiation-regulated genes and pathways in response to radiations of varying ionization density. The fact that densely ionizing radiations can affect different gene families than sparsely ionizing radiations, and that the effects are dose- and time-dependent has opened up new areas of future research. The complex microenvironment of the stroma, and the significant contributions of the immune response have added to our understanding of tissue-specific differences across the linear energy transfer (LET) spectrum. The importance of targeted vs. nontargeted effects remain a thorny, but elusive and important contributor to chronic low dose radiation effects of variable LET that still needs further research. The induction of cancer is also LET-dependent, suggesting different mechanisms of action across the gradient of ionization density. The focus of this 35th Lauriston S. Taylor Lecture is to chronicle the step-by-step acquisition of experimental clues that have refined our understanding of what makes particle radiation so effective, with emphasis on the example of radiation effects on the crystalline lens of the human eye. PMID:23032880

Lactoferricin mediates anabolic and anti-catabolic effects in the intervertebral disc.

PubMed

Kim, Jae-Sung; Ellman, Michael B; An, Howard S; Yan, Dongyao; van Wijnen, Andre J; Murphy, Gillian; Hoskin, David W; Im, Hee-Jeong

2012-04-01

Lactoferricin (LfcinB) antagonizes biological effects mediated by angiogenic and catabolic growth factors, in addition to pro-inflammatory cytokines and chemokines in human endothelial cells and tumor cells. However, the effect of LfcinB on intervertebral disc (IVD) cell metabolism has not yet been investigated. Using bovine nucleus pulposus (NP) cells, we analyzed the effect of LfcinB on proteoglycan (PG) accumulation, PG synthesis, and anabolic gene expression. We assessed expression of genes for matrix-degrading enzymes such as matrix metalloproteases (MMPs) and a disintegrin-like and metalloprotease with thrombospondin motifs (ADAMTS family), as well as their endogenous inhibitors, tissue inhibitor of metalloproteases (TIMPs). In order to understand the specific molecular mechanisms by which LfcinB exerts its biological effects, we investigated intracellular signaling pathways in NP cells. LfcinB increased PG accumulation mainly via PG synthesis in a dose-dependent manner. Simultaneously, LfcinB dose-dependently downregulated catabolic enzymes. LfcinB's anti-catabolic effects were further demonstrated by a dose-dependent increase in multiple TIMP family members. Our results demonstrate that ERK and/or p38 mitogen-activated protein kinase pathways are the key signaling cascades that exert the biological effects of LfcinB in NP cells, regulating transcription of aggrecan, SOX-9, TIMP-1, TIMP-2, TIMP-3, and iNOS. Our results suggest that LfcinB has anabolic and potent anti-catabolic biological effects on bovine IVD cells that may have considerable promise in the treatment of disc degeneration in the future. Copyright © 2011 Wiley Periodicals, Inc.

Blood gene expression profiling of an early acetaminophen response.

PubMed

Bushel, P R; Fannin, R D; Gerrish, K; Watkins, P B; Paules, R S

2017-06-01

Acetaminophen can adversely affect the liver especially when overdosed. We used whole blood as a surrogate to identify genes as potential early indicators of an acetaminophen-induced response. In a clinical study, healthy human subjects were dosed daily with 4 g of either acetaminophen or placebo pills for 7 days and evaluated over the course of 14 days. Alanine aminotransferase (ALT) levels for responders to acetaminophen increased between days 4 and 9 after dosing, and 12 genes were detected with expression profiles significantly altered within 24 h. The early responsive genes separated the subjects by class and dose period. In addition, the genes clustered patients who overdosed on acetaminophen apart from controls and also predicted the exposure classifications with 100% accuracy. The responsive genes serve as early indicators of an acetaminophen exposure, and their gene expression profiles can potentially be evaluated as molecular indicators for further consideration.

Blood Gene Expression Profiling of an Early Acetaminophen Response

PubMed Central

Bushel, Pierre R.; Fannin, Rick D.; Gerrish, Kevin; Watkins, Paul B.; Paules, Richard S.

2018-01-01

Acetaminophen can adversely affect the liver especially when overdosed. We used whole blood as a surrogate to identify genes as potential early indicators of an acetaminophen-induced response. In a clinical study, healthy human subjects were dosed daily with 4g of either acetaminophen or placebo pills for 7 days and evaluated over the course of 14 days. Alanine aminotransferase (ALT) levels for responders to acetaminophen increased between days 4 and 9 after dosing and 12 genes were detected with expression profiles significantly altered within 24 hrs. The early responsive genes separated the subjects by class and dose period. In addition, the genes clustered patients who overdosed on acetaminophen apart from controls and also predicted the exposure classifications with 100% accuracy. The responsive genes serve as early indicators of an acetaminophen exposure and their gene expression profiles can potentially be evaluated as molecular indicators for further consideration. PMID:26927286

Individual Genetic Susceptibility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eric J. Hall

2008-12-08

Risk estimates derived from epidemiological studies of exposed populations, as well as the maximum permissible doses allowed for occupational exposure and exposure of the public to ionizing radiation are all based on the assumption that the human population is uniform in its radiosensitivity, except for a small number of individuals, such as ATM homozygotes who are easily identified by their clinical symptoms. The hypothesis upon which this proposal is based is that the human population is not homogeneous in radiosensitiviry, but that radiosensitive sub-groups exist which are not easy to identify. These individuals would suffer an increased incidence of detrimentalmore » radiation effects, and distort the shape of the dose response relationship. The radiosensitivity of these groups depend on the expression levels of specific proteins. The plan was to investigate the effect of 3 relatively rare, high penetrate genes available in mice, namely Atm, mRad9 & Brca1. The purpose of radiation protection is to prevent! deterministic effects of clinical significance and limit stochastic effects to acceptable levels. We plan, therefore to compare with wild type animals the radiosensitivity of mice heterozygous for each of the genes mentioned above, as well as double heterozygotes for pairs of genes, using two biological endpoints: a) Ocular cataracts as an important and relevant deterministic effect, and b) Oncogenic transformation in cultured embryo fibroblasts, as a surrogate for carcinogenesis, the most relevant stochastic effect.« less

[Effects of berberine on mRNA expression levels of PPARγ and adipocytokines in insulin-resistant adipocytes].

PubMed

Tu, Jun; Luo, Xin-Xin; Li, Bing-Tao; Li, Yu; Xu, Guo-Liang

2016-06-01

Adipocytokines are closely associated with insulin resistance (IR) in adipose tissues, and they are more and more seriously taken in the study of the development of diabetes. This experiment was mainly to study the effect of berberine on mRNA expression levels of PPARγ and adipocytokines in insulin resistant adipocytes, and investigate the molecular mechanism of berberine in enhancing insulin sensitization and application advantages of droplet digital PCR (ddPCR). ddPCR absolute quantification analysis was taken in this experiment to simply and intuitively determine the appropriate reference genes. ddPCR and quantitative Real-time PCR (qPCR) were used to compare the effect of different doses of berberine (10, 20, 50, 100 μmol•L⁻¹) on mRNA expression levels of PPARγ, adiponectin, resistin and leptin in IR 3T3-L1adipocytes. Antagonist GW9662 was added to study the inherent correlation between PPARγ and adiponectin mRNA expression levels. ddPCR results showed that the expression level of β-actin in adipocytes was stable, and suitable as reference gene for normalization of quantitative PCR data. Both of ddPCR and qPCR results showed that, as compared with IR models, the mRNA expression levels of adiponectin were decreased in the treatment with berberine (10, 20, 50, 100 μmol•L⁻¹) in a dose-dependent manner (P<0.01); the expression of PPARγ was decreased by 20, 50, 100 μmol•L⁻¹ berberine in a dose-dependent manner in qPCR assay (P<0.01) and decreased only by 50 and 100 μmol•L⁻¹ berberine in ddPCR assay (P<0.05). PPARγ specific antagonist GW9662 intervention experiment showed that adiponectin gene expression was directly relevant with PPARγ (P<0.05). ddPCR probe assay showed that various doses of berberine could significantly reduce mRNA expression levels of resistin and leptin (P<0.01) in a dose-dependent manner. In conclusion, berberine enhanced insulin sensitization effect not by up-regulating adiponect in expression of transcriptional level in PPARγ-dependent manner, but may by the elevated multimerization of adiponectin in the posttranslational regulation level. Berberine down-regulated the resistin and leptin expression levels, which could alleviate lipolysis and improve IR in adipocytes. ddPCR provided better sensitivity and linear range than qPCR, with obvious technical advantages for the detection of low abundance expression of target genes. Copyright© by the Chinese Pharmaceutical Association.

Transciptomic study of mucosal immune, antioxidant and growth related genes and non-specific immune response of common carp (Cyprinus carpio) fed dietary Ferula (Ferula assafoetida).

PubMed

Safari, Roghieh; Hoseinifar, Seyed Hossein; Nejadmoghadam, Shabnam; Jafar, Ali

2016-08-01

A 8-weeks feeding trial was conducted to examine the effects of different levels (0, 0.5, 1 and 2%) of dietary Ferula (Ferula assafoetida) on expression of antioxidant enzymes (GSR, GPX and GSTA), immune (TNF-alpha, IL1B, IL- 8 and LYZ) and growth (GH, IGF1 and Ghrl) genes as well as cutaneous mucus and serum non-specific immune response in common carp. The results revealed Ferula significantly increased antioxidant gene expression (GSR and GSTA) in a dose dependent manner (P < 0.05). The expression of immune growth related genes were significantly higher in Ferula fed fish compared control group (P < 0.05). The effects of Ferula on expression of genes was more pronounced in higher doses. Feeding on Ferula supplemented diet remarkably increased skin mucus lysozyme activity (P < 0.05). However, evaluation of mucus total Ig and protease activity revealed no significant difference between control and treated groups (P > 0.05). Regarding non-specific humoral response, serum total Ig, lysozyme and ACH50 showed no remarkable variation between Ferula fed carps and control group (P > 0.05). These results indicated up-regulation of growth and health related genes in Ferula fed common carp. Further studies using pathogen or stress challenge is required to conclude that transcriptional modulation is beneficial in common carp. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison between effects of free curcumin and curcumin loaded NIPAAm-MAA nanoparticles on telomerase and PinX1 gene expression in lung cancer cells.

PubMed

Badrzadeh, Fariba; Akbarzadeh, Abolfazl; Zarghami, Nosratollah; Yamchi, Mohammad Rahmati; Zeighamian, Vahide; Tabatabae, Fateme Sadate; Taheri, Morteza; Kafil, Hossein Samadi

2014-01-01

Herbal compounds such as curcumin which decrease telomerase and gene expression have been considered as beneficial tools for lung cancer treatment. In this article, we compared the effects of pure curcumin and curcumin-loaded NIPAAm-MAA nanoparticles on telomerase and PinX1 gene expression in a lung cancer cell line. A tetrazolium-based assay was used for determination of cytotoxic effects of curcumin on the Calu-6 lung cancer cell line and telomerase and pinX1 gene expression was measured with real-time PCR. MTT assay showed that Curcumin-loaded NIPAAm-MAA inhibited the growth of the Calu-6 lung cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of curcumin-loaded NIPAAm-MAA increased while expression of the PinX1 gene became elevated. The results showed that curcumin- loaded- NIPAAm-MAA exerted cytotoxic effects on the Calu-6 cell line through down-regulation of telomerase and stimulation of pinX1 gene expression. NIPPAm-MAA could be good carrier for such kinds of hydrophobic agent.

Transcription factors and stress response gene alterations in human keratinocytes following Solar Simulated Ultra Violet Radiation.

PubMed

Marais, Thomas L Des; Kluz, Thomas; Xu, Dazhong; Zhang, Xiaoru; Gesumaria, Lisa; Matsui, Mary S; Costa, Max; Sun, Hong

2017-10-19

Ultraviolet radiation (UVR) from sunlight is the major effector for skin aging and carcinogenesis. However, genes and pathways altered by solar-simulated UVR (ssUVR), a mixture of UVA and UVB, are not well characterized. Here we report global changes in gene expression as well as associated pathways and upstream transcription factors in human keratinocytes exposed to ssUVR. Human HaCaT keratinocytes were exposed to either a single dose or 5 repetitive doses of ssUVR. Comprehensive analyses of gene expression profiles as well as functional annotation were performed at 24 hours post irradiation. Our results revealed that ssUVR modulated genes with diverse cellular functions changed in a dose-dependent manner. Gene expression in cells exposed to a single dose of ssUVR differed significantly from those that underwent repetitive exposures. While single ssUVR caused a significant inhibition in genes involved in cell cycle progression, especially G2/M checkpoint and mitotic regulation, repetitive ssUVR led to extensive changes in genes related to cell signaling and metabolism. We have also identified a panel of ssUVR target genes that exhibited persistent changes in gene expression even at 1 week after irradiation. These results revealed a complex network of transcriptional regulators and pathways that orchestrate the cellular response to ssUVR.

Molecular analysis of the inhibition of interleukin-8 production by dexamethasone in a human fibrosarcoma cell line.

PubMed Central

Mukaida, N; Gussella, G L; Kasahara, T; Ko, Y; Zachariae, C O; Kawai, T; Matsushima, K

1992-01-01

In order to analyse the effects of glucocorticoids on interleukin-8 (IL-8) production more precisely, we examined the effects of dexamethasone on IL-8 production at the molecular level in a human fibrosarcoma cell line, 8387, which IL-1 induces to express IL-8 messenger RNA (mRNA) and to secrete IL-8. Over a wide dose range, dexamethasone inhibited IL-8 production induced by IL-1 alpha stimulation. Northern blotting analysis showed that dexamethasone also inhibited the IL-8 mRNA accumulation in a similar dose-related manner. Nuclear run-off assay revealed that dexamethasone decreased the transcription of the IL-8 gene and the degree of inhibition of transcription correlated well with the inhibition of IL-8 production, suggesting that the action of glucocorticoids is mainly at the transcriptional level. Furthermore, transfection with chloramphenicol acetyl transferase (CAT) expression vectors inserted with the 5'-deleted IL-8 gene demonstrated that the 5'-flanking region which contains the glucocorticoid response element (GRE) was mainly involved in the dexamethasone-induced repression of the IL-8 gene. These data suggest that the inhibition of the IL-8 gene transcription by glucocorticoids occurs through the interaction of the glucocorticoid receptor complex with GRE in the 5'-flanking region of the IL-8 gene. Images Figure 1 Figure 2 Figure 3 PMID:1592440

Examining Radiation-Induced In Vivo and In Vitro Gene Expression Changes of the Peripheral Blood in Different Laboratories for Biodosimetry Purposes: First RENEB Gene Expression Study.

PubMed

Abend, M; Badie, C; Quintens, R; Kriehuber, R; Manning, G; Macaeva, E; Njima, M; Oskamp, D; Strunz, S; Moertl, S; Doucha-Senf, S; Dahlke, S; Menzel, J; Port, M

2016-02-01

The risk of a large-scale event leading to acute radiation exposure necessitates the development of high-throughput methods for providing rapid individual dose estimates. Our work addresses three goals, which align with the directive of the European Union's Realizing the European Network of Biodosimetry project (EU-RENB): 1. To examine the suitability of different gene expression platforms for biodosimetry purposes; 2. To perform this examination using blood samples collected from prostate cancer patients (in vivo) and from healthy donors (in vitro); and 3. To compare radiation-induced gene expression changes of the in vivo with in vitro blood samples. For the in vitro part of this study, EDTA-treated whole blood was irradiated immediately after venipuncture using single X-ray doses (1 Gy/min(-1) dose rate, 100 keV). Blood samples used to generate calibration curves as well as 10 coded (blinded) samples (0-4 Gy dose range) were incubated for 24 h in vitro, lysed and shipped on wet ice. For the in vivo part of the study PAXgene tubes were used and peripheral blood (2.5 ml) was collected from prostate cancer patients before and 24 h after the first fractionated 2 Gy dose of localized radiotherapy to the pelvis [linear accelerator (LINAC), 580 MU/min, exposure 1-1.5 min]. Assays were run in each laboratory according to locally established protocols using either microarray platforms (2 laboratories) or qRT-PCR (2 laboratories). Report times on dose estimates were documented. The mean absolute difference of estimated doses relative to the true doses (Gy) were calculated. Doses were also merged into binary categories reflecting aspects of clinical/diagnostic relevance. For the in vitro part of the study, the earliest report time on dose estimates was 7 h for qRT-PCR and 35 h for microarrays. Methodological variance of gene expression measurements (CV ≤10% for technical replicates) and interindividual variance (≤twofold for all genes) were low. Dose estimates based on one gene, ferredoxin reductase (FDXR), using qRT-PCR were as precise as dose estimates based on multiple genes using microarrays, but the precision decreased at doses ≥2 Gy. Binary dose categories comprising, for example, unexposed compared with exposed samples, could be completely discriminated with most of our methods. Exposed prostate cancer blood samples (n = 4) could be completely discriminated from unexposed blood samples (n = 4, P < 0.03, two-sided Fisher's exact test) without individual controls. This could be performed by introducing an in vitro-to-in vivo correction factor of FDXR, which varied among the laboratories. After that the in vitro-constructed calibration curves could be used for dose estimation of the in vivo exposed prostate cancer blood samples within an accuracy window of ±0.5 Gy in both contributing qRT-PCR laboratories. In conclusion, early and precise dose estimates can be performed, in particular at doses ≤2 Gy in vitro. Blood samples of prostate cancer patients exposed to 0.09-0.017 Gy could be completely discriminated from pre-exposure blood samples with the doses successfully estimated using adjusted in vitro-constructed calibration curves.

Clinical and genetic factors associated with warfarin maintenance dose in northern Chinese patients with mechanical heart valve replacement

PubMed Central

Liu, Rui; Cao, Jian; Zhang, Qian; Shi, Xin-Miao; Pan, Xiao-Dong; Dong, Ran

2017-01-01

Abstract The effects of genetic variants on warfarin dosing vary among different ethnic groups, especially in the Chinese population. The objective of this study was to recruit patients through a rigorous experimental design and to perform a comprehensive screen to identify gene polymorphisms that may influence warfarin dosing in northern Han Chinese patients with mechanical heart valve replacement. Consenting patients (n = 183) with a stable warfarin dose were included in this study. Ninety-six single nucleotide polymorphisms (SNPs) in 30 genes involved in warfarin pharmacological pathways were genotyped using the Illumina SNP GoldenGate Assay, and their associations with warfarin dosing were assessed using univariate regression analysis with post hoc comparison using least significant difference analysis. Multiple linear regression was performed by incorporating patients’ clinical and genetic data to create a new algorithm for warfarin dosing. From the 96 SNPs analyzed, VKORC1 rs9923231, CYP1A2 rs2069514, CYP3A4 rs28371759, and APOE rs7412 were associated with higher average warfarin maintenance doses, whereas CYP2C9 rs1057910, EPHX1 rs2260863, and CYP4F2 rs2189784 were associated with lower warfarin doses (P < 0.05). Multiple linear regression analysis could estimate 44.4% of warfarin dose variability consisting of, in decreasing order, VKORC1 rs9923231 (14.2%), CYP2C9∗3 (9.6%), body surface area (6.7%), CYP1A2 rs2069514 (3.7%), age (2.7%), CYP3A4 rs28371759 (2.5%), CYP4F2 rs2108622 (1.9%), APOE rs7412 (1.7%), and VKORC1 rs2884737 (1.4%). In the dosing algorithm we developed, we confirmed the strongest effects of VKORC1, CYP2C9 on warfarin dosing. In the limited sample set, we also found that novel genetic predictors (CYP1A2, CYP3A4, APOE, EPHX1, CYP4F2, and VKORC1 rs2884737) may be associated with warfarin dosing. Further validation is needed to assess our results in larger independent northern Chinese samples. PMID:28079798

Bromuconazole-induced hepatotoxicity is accompanied by upregulation of PXR/CYP3A1 and downregulation of CAR/CYP2B1 gene expression.

PubMed

Abdelhadya, Doaa H; El-Magd, Mohammed Abu; Elbialy, Zizy I; Saleh, Ayman A

2017-09-01

Despite widespread use of bromuconazole as a pesticide for food crops and fruits, limited studies have been done to evaluate its toxic effects. Here, we evaluated the hepatotoxic effect of bromuconazole using classical toxicological (biochemical analysis and histopathological examination) and gene-based molecular methods. Male rats were treated either orally or topically with bromuconazole at doses equal to no observed adverse effect level (NOAEL) and 1/10 LD50 for 90 d. Bromuconazole increased activities of liver enzymes (ALT, AST, ALP, and ACP), and levels of bilirubin. It also induced hepatic oxidative stress as evidenced by significant decrease in the activities of superoxide dismutase (SOD), and significant increase in levels of malondialdehyde (MDA) in liver. In addition, bromuconazole caused an increase in liver weights and necrobiotic changes (vacuolation and hepatocellular hypertrophy). It also strongly induced the expression of PXR and its downstream target CYP3A1 gene as well as the activity of CYP3A1. However, it inhibited the expression of CAR and its downstream target CYP2B1 gene without significant changing in CYP2B1 activity. Overall, the oral route showed higher hepatotoxic effect and molecular changes than the dermal route and all changes were dose dependent. This is the first investigation to report that bromuconazole-induced liver oxidative damage is accompanied by upregulation of PXR/CYP3A1 and downregulation of CAR/CYP2B1.

Opposite effects of tamoxifen on metabolic syndrome-induced bladder and prostate alterations: a role for GPR30/GPER?

PubMed

Comeglio, P; Morelli, A; Cellai, I; Vignozzi, L; Sarchielli, E; Filippi, S; Maneschi, E; Corcetto, F; Corno, C; Gacci, M; Vannelli, G B; Maggi, M

2014-01-01

BPH and LUTS have been associated to obesity, hypogonadism, and metabolic syndrome (MetS). MetS-induced prostate and bladder alterations, including inflammation and tissue remodeling, have been related to a low-testosterone and high-estrogen milieu. In addition to ERs, GPR30/GPER is able to mediate several estrogenic non-genomic actions. Supplementing a subgroup of MetS rabbits with tamoxifen, we analyzed the in vivo effects on MetS-induced prostate and bladder alterations. The effects of selective ER/GPER ligands and GPER silencing on prostate inflammation were also studied in vitro using hBPH cells. ERα, ERβ, and PR expression was upregulated in MetS bladder, where tamoxifen decreased ERα and PR expression, further stimulating ERβ. In addition, tamoxifen-dosing decreased MetS-induced overexpression of inflammatory and tissue remodeling genes. In prostate, sex steroid receptors, pro-inflammatory and pro-fibrotic genes were upregulated in MetS. However, tamoxifen did not affect them and even increased COX-2. In hBPH cells, 17β-estradiol increased IL-8 secretion, an effect blunted by co-treatment with GPER antagonist G15 but not by ER antagonist ICI 182,780, which further increased it. GPER agonist G1 dose-dependently (IC50  = 1.6 nM) induced IL-8 secretion. In vitro analysis demonstrated that GPER silencing reverted these stimulatory effects. GPER can be considered the main mediator of estrogen action in prostate, whereas in bladder the mechanism appears to rely on ERα, as indicated by in vivo experiments with tamoxifen dosing. Limiting the effects of the MetS-induced estrogen action via GPER could offer new perspectives in the management of BPH/LUTS, whereas tamoxifen dosing showed potential benefits in bladder. © 2013 Wiley Periodicals, Inc.

Dose related shifts in the developmental progress of chick embryos exposed to mobile phone induced electromagnetic fields.

PubMed

Zareen, Nusrat; Khan, Muhammad Yunus; Minhas, Liaqat Ali

2009-01-01

The possible adverse effects of Electromagnetic Fields (EMFs) emitted from mobile phones present a major public concern today. Some studies indicate EMFs effects on genes, free radical production, immunological and carcinogenic effects. On the other hand there are studies which do not support the hypothesis of any biological impacts of EMFs. This study was designed to observe the effects of mobile phone induced EMFs on survival and general growth and development of chick embryo, investigating dose-response relationship if any. This was an experimental study in which developing chick embryos were exposed to different doses of mobile phone induced EMFs. For this purpose a mobile phone was placed in the incubator in the centre of fertilised eggs in silent ringing mode and was 'rung' upon from any other line or cell phone. After incubation for 10 or 15 days the eggs were opened and the developmental mile-stones of the surviving embryos were compared with the non exposed subgroup. EMFs exposure significantly decreased the survivability of the chick embryos. The lower doses of EMFs caused growth retardation. However, this effect of growth retardation reallocated to partial growth enhancement on increasing the dose of EMFs and shifted over to definite growth enhancement on further raising the dose. There is an adverse effect of EMFs exposure on embryo survivability. Chick embryos developmental process is influenced by EMFs. However, these effects are variable depending upon the dose of EMFs exposure.

The effect of high concentrations of glufosinate ammonium on the yield components of transgenic spring wheat (Triticum aestivum L.) constitutively expressing the bar gene.

PubMed

Áy, Zoltán; Mihály, Róbert; Cserháti, Mátyás; Kótai, Éva; Pauk, János

2012-01-01

We present an experiment done on a bar(+) wheat line treated with 14 different concentrations of glufosinate ammonium-an effective component of nonselective herbicides-during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose was not enough to inhibit the germination of transgenic plants expressing the bar gene. Extremely high concentrations of glufosinate ammonium caused a bushy phenotype, significantly lower numbers of grains per spike, and thousand kernel weights. Concerning the productivity, we observed that concentrations of glufosinate ammonium 64 times the lethal dose did not lead to yield depression. Our results draw attention to the possibilities implied in the transgenic approaches.

Cytochrome P450 2C9 gene polymorphism and warfarin maintenance dosage in pediatric patients: A systematic review and meta-analysis.

PubMed

Zhang, Jinhua; Tian, Lihong; Huang, Jinlong; Huang, Sihan; Chai, Tingting; Shen, Jianzhen

2017-02-01

To assess the effect of Cytochrome P450 2C9 (CYP2C9) gene polymorphism on pediatric warfarin maintenance dosage requirement. A previously developed search strategy was conducted in PubMed, EMBASE, and the Cochrane Library. Eligible studies published prior to January 27, 2016, were identified and compared against strict inclusion/exclusion criteria. Required data were extracted, and researchers were consulted for additional data if needed. Review Manager version 5.2.3 software was used to analyze the relationship between CYP2C9 polymorphisms and warfarin maintenance doses in pediatric patients. Eight articles with a combined total of 507 pediatric patients were included in the meta-analysis. Maintenance warfarin doses in patients with CYP2C9 *1/*2 genotype, CYP2C9 *1/*3 genotype, and CYP2C9 variant carriers which contain at least one variant allele (*2 or *3) were from 15% to 41% lower than doses in patients with the wild-type allele (CYP2C9 *1/*1): All differences were significant with P-values <.05. The Fontan procedure as a medical indication for anticoagulation was also associated with a lower warfarin maintenance dose; however, target INR range was not. We found that CYP2C9 gene polymorphism (referring to the presence of *1/*2, *1/*3, and variant genotypes in the population in addition to the wild type) was significantly associated with decreased warfarin maintenance dose requirements. Additionally, a specific indication for warfarin, the Fontan procedure, was associated with a lower daily warfarin dose. However, the results of our study require confirmation from more research with larger numbers of pediatric patients. © 2016 John Wiley & Sons Ltd.

Multiparametric Determination of Radiation Risk

NASA Technical Reports Server (NTRS)

Richmond, Robert C.

2003-01-01

Predicting risk of human cancer following exposure to ionizing space radiation is challenging in part because of uncertainties of low-dose distribution amongst cells, of unknown potentially synergistic effects of microgravity upon cellular protein-expression, and of processing dose-related damage within cells to produce rare and late-appearing malignant transformation, degrade the confidence of cancer risk-estimates. The NASA- specific responsibility to estimate the risks of radiogenic cancer in a limited number of astronauts is not amenable to epidemiologic study, thereby increasing this challenge. Developing adequately sensitive cellular biodosimeters that simultaneously report 1) the quantity of absorbed close after exposure to ionizing radiation, 2) the quality of radiation delivering that dose, and 3) the risk of developing malignant transformation by the cells absorbing that dose could be useful for resolving these challenges. Use of a multiparametric cellular biodosimeter is suggested using analyses of gene-expression and protein-expression whereby large datasets of cellular response to radiation-induced damage are obtained and analyzed for expression-profiles correlated with established end points and molecular markers predictive for cancer-risk. Analytical techniques of genomics and proteomics may be used to establish dose-dependency of multiple gene- and protein- expressions resulting from radiation-induced cellular damage. Furthermore, gene- and protein-expression from cells in microgravity are known to be altered relative to cells grown on the ground at 1g. Therefore, hypotheses are proposed that 1) macromolecular expression caused by radiation-induced damage in cells in microgravity may be different than on the ground, and 2) different patterns of macromolecular expression in microgravity may alter human radiogenic cancer risk relative to radiation exposure on Earth. A new paradigm is accordingly suggested as a national database wherein genomic and proteomic datasets are registered and interrogated in order to provide statistically significant dose-dependent risk estimation of radiogenic cancer in astronauts.

Effects of trimethoprim on life history parameters, oxidative stress, and the expression of cytochrome P450 genes in the copepod Tigriopus japonicus.

PubMed

Han, Jeonghoon; Lee, Min-Chul; Kim, Duck-Hyun; Lee, Young Hwan; Park, Jun Chul; Lee, Jae-Seong

2016-09-01

Trimethoprim (TMP) is an antibiotic that has been detected in various environments including marine habitats; however, the toxic effects of TMP are poorly understood in non-target marine organisms. In this study, the effects of TMP on mortality, development, reproduction, intracellular reactive oxygen species (ROS) levels, and transcription levels of antioxidant and xenobiotic detoxification-related enzyme genes were investigated in the copepod Tigriopus japonicus. The TMP half lethal dose at 48 h (LC50-48 h) in nauplius and TMP LC50-96 h in adult T. japonicus copepods was determined as 156 mg/L and 200 mg/L, respectively. In TMP-exposed T. japonicus, delayed developmental time and impaired reproduction were observed as harmful effects on the life history parameters. Increased ROS levels were also shown in response to TMP exposure at the highest concentration (100 mg/L TMP) and the expression of antioxidant- (e.g. GST-kappa, GST-sigma) and xenobiotic detoxification (e.g. CYPs)-related genes were upregulated in a time and/or dose-dependent manner in response to TMP. Particularly, significant upregulation of three CYP genes (Tj-CYP3024A2, Tj-CYP3024A3 and Tj-CYP3027C2) were examined, suggesting that these CYP genes are likely playing an important role in the TMP detoxification metabolism in T. japonicus. In summary, we found that TMP induced oxidative stress via the transcriptional regulation of antioxidant- and xenobiotic detoxification-related genes, leading to changes in life history parameters such as developmental delay and reproduction impairment. Three Tj-CYP genes (Tj-CYP3024A2, Tj-CYP3024A3 and Tj-CYP3027C2) could be useful as potential T. japonicus biomarkers in response to antibiotics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gene selection with multiple ordering criteria.

PubMed

Chen, James J; Tsai, Chen-An; Tzeng, Shengli; Chen, Chun-Houh

2007-03-05

A microarray study may select different differentially expressed gene sets because of different selection criteria. For example, the fold-change and p-value are two commonly known criteria to select differentially expressed genes under two experimental conditions. These two selection criteria often result in incompatible selected gene sets. Also, in a two-factor, say, treatment by time experiment, the investigator may be interested in one gene list that responds to both treatment and time effects. We propose three layer ranking algorithms, point-admissible, line-admissible (convex), and Pareto, to provide a preference gene list from multiple gene lists generated by different ranking criteria. Using the public colon data as an example, the layer ranking algorithms are applied to the three univariate ranking criteria, fold-change, p-value, and frequency of selections by the SVM-RFE classifier. A simulation experiment shows that for experiments with small or moderate sample sizes (less than 20 per group) and detecting a 4-fold change or less, the two-dimensional (p-value and fold-change) convex layer ranking selects differentially expressed genes with generally lower FDR and higher power than the standard p-value ranking. Three applications are presented. The first application illustrates a use of the layer rankings to potentially improve predictive accuracy. The second application illustrates an application to a two-factor experiment involving two dose levels and two time points. The layer rankings are applied to selecting differentially expressed genes relating to the dose and time effects. In the third application, the layer rankings are applied to a benchmark data set consisting of three dilution concentrations to provide a ranking system from a long list of differentially expressed genes generated from the three dilution concentrations. The layer ranking algorithms are useful to help investigators in selecting the most promising genes from multiple gene lists generated by different filter, normalization, or analysis methods for various objectives.

The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

DOE PAGES

Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; ...

2014-01-01

Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type ( Trp53+/+) and heterozygous ( Trp53+/-) mice. The dose response for Trp53+/+ mice showed highermore » initial levels of radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.« less

Dose- and time-dependent gene expression alterations in prostate and colon cancer cells after in vitro exposure to carbon ion and X-irradiation

PubMed Central

Suetens, Annelies; Moreels, Marjan; Quintens, Roel; Soors, Els; Buset, Jasmine; Chiriotti, Sabina; Tabury, Kevin; Gregoire, Vincent; Baatout, Sarah

2015-01-01

Hadrontherapy is an advanced form of radiotherapy that uses beams of charged particles (such as protons and carbon ions). Compared with conventional radiotherapy, the main advantages of carbon ion therapy are the precise absorbed dose localization, along with an increased relative biological effectiveness (RBE). This high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. Currently, hadrontherapy is being used for the treatment of specific types of cancer. Previous in vitro studies have shown that, under certain circumstances, exposure to charged particles may inhibit cell motility and migration. In the present study, we investigated the expression of four motility-related genes in prostate (PC3) and colon (Caco-2) cancer cell lines after exposure to different radiation types. Cells were irradiated with various absorbed doses (0, 0.5 and 2 Gy) of accelerated 13C-ions at the GANIL facility (Caen, France) or with X-rays. Clonogenic assays were performed to determine the RBE. RT-qPCR analysis showed dose- and time-dependent changes in the expression of CCDC88A, FN1, MYH9 and ROCK1 in both cell lines. However, whereas in PC3 cells the response to carbon ion irradiation was enhanced compared with X-irradiation, the effect was the opposite in Caco-2 cells, indicating cell-type–specific responses to the different radiation types. PMID:25190155

Effects of dietary oxidized konjac glucomannan sulfates (OKGMS) and acidolysis-oxidized konjac glucomannan (A-OKGM) on the immunity and expression of immune-related genes of Schizothorax prenanti.

PubMed

Chen, Mingrui; Wang, Hongjie; Yan, Qiuping; Zheng, Qiaoran; Yang, Min; Lv, Zhenzhen; He, Mei; Feng, Limei; Zhao, Jiaqi; Tang, Tingting; Wu, Yinglong

2016-09-01

In the present study, konjac glucomannan (KGM) was degraded by H2O2, and then used trisulfonated sodium amine and HCl, individually, to obtain two kinds of derivatives: oxidized konjac glucomannan sulfates (OKGMS) and acidolysis-oxidized konjac glucomannan (A-OKGM). The effects of two OKGM modified products on the immune parameters and expressions of toll-like receptor 22 (TLR22), myeloid differentiation factor 88 (MyD88) and interferon regulatory factors 7 (IRF7) genes in Schizothorax prenanti were determined. The alternative haemolytic complement (ACH50) activity was found to be significantly increased by the OKGMS diets. The immunoglobulin M (IgM) level was significantly enhanced by the OKGMS diets. The lysozyme activity was significantly increased by both OKGMS and A-OKGM diets. The superoxide dismutase (T-SOD) activity in fish fed with all doses of OKGMS diets was significantly higher than that in fish fed with basal diet. The glutathione peroxidase (GSH-PX) activity in fish fed with 0.8% and 1.6% A-OKGM diets was significantly higher than control group. The malondialdehyde (MDA) level was significantly decreased by both OKGMS and A-OKGM diets. The 0.8% A-OKGM diet significantly up-regulated TLR22 gene expression in the head kidney and spleen. TLR22 gene expression was significantly promoted by all OKGMS diets in the mesonephros and liver. The MyD88 mRNA level in 1.6% A-OKGM group significantly increased in the head kidney. The low dose of OKGMS significantly induced the MyD88 gene expression in the mesonephros, gut and liver, while 0.8% A-OKGM group also showed a significantly enhanced MyD88 mRNA expression in the gut. High dose of OKGMS significantly increased the IRF7 mRNA expression in the mesonephros and spleen. Fish fed with low dose of A-OKGM showed significantly higher expression of IRF7 in the gut and liver. Present study suggested that OKGMS and A-OKGM can act as immunostimulant to improve the immune indexes and up-regulate the immune-related gene expressions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plasma Pharmacokinetics of Veledimex, a Small-Molecule Activator Ligand for a Proprietary Gene Therapy Promoter System, in Healthy Subjects.

PubMed

Cai, Hongliang; Sun, Lei; Miao, John; Krishman, Suma; Lebel, Francois; Barrett, John A

2017-05-01

Major obstacles to developing effective immunotherapy are the ability of tumors to escape the immune system and the toxicity associated with systemic administration. To overcome these challenges, a gene delivery platform technology, RheoSwitch Therapeutic System (RTS), has been developed to enable the regulated expression of a target gene, Ad-RTS-IL-12, administered intratumorally, where IL-12 expression is controlled via the administration of an oral activator ligand, veledimex. Pharmacokinetics in healthy human subjects indicated that veledimex plasma exposure increased with increasing dose after single- and multiple-dose administration in Labrasol slurry and F-22 capsule formulations. No apparent formulation or sex-related difference in veledimex pharmacokinetics (PK) was observed. Minimal or no plasma accumulation of veledimex was observed after once-daily oral administration for 14 days. Veledimex steady state in plasma was reached after 5 daily doses. Food consumption prior to veledimex administration prolonged and enhanced absorption with no impact on the elimination rate and extent of metabolism of veledimex, resulting in significantly increased systemic exposure to veledimex and its 2 major circulating metabolites. Overall, veledimex was well tolerated and exhibited a PK profile supportive of once-daily dosing. For enhanced efficacy, veledimex should be taken under fed conditions to ensure optimal absorption and sufficient systemic exposure. © 2016, The American College of Clinical Pharmacology.

Cytotoxic effect of the Her-2/Her-1 inhibitor PKI-166 on renal cancer cells expressing the connexin 32 gene.

PubMed

Fujimoto, Eriko; Yano, Tomohiro; Sato, Hiromi; Hagiwara, Kiyokazu; Yamasaki, Hiroshi; Shirai, Sumiko; Fukumoto, Keiko; Hagiwara, Hiromi; Negishi, Etsuko; Ueno, Koichi

2005-02-01

We have reported that connexin (Cx) 32 acts as a tumor suppressor gene in renal cancer cells partly due to Her-2 inactivation. Here, we determined if a Her-2/Her-1 inhibitor (PKI-166) can enhance the tumor-suppressive effect of Cx32 in Caki-2 cells from human renal cell carcinoma. The expression of Cx32 in Caki-2 cells was required for PKI-166-induced cytotoxic effect at lower doses. The cyctotoxicity was dependent on the occurrence of apoptosis and partly mediated by Cx32-driven gap junction intercellular communications. These results suggest that PKI-166 further supports the tumor-suppressive effect of the Cx32 gene in renal cancer cells through the induction of apoptosis.

The neuropsychology of normal aging and preclinical Alzheimer’s disease

PubMed Central

Caselli, Richard J.; Locke, Dona E.C.; Dueck, Amylou C.; Knopman, David S.; Woodruff, Bryan K.; Hoffman-Snyder, Charlene; Rademakers, Rosa; Fleisher, Adam S.; Reiman, Eric M.

2013-01-01

Background An NIA-sponsored workgroup on preclinical Alzheimer’s disease (AD) articulated the need to characterize cognitive differences between normal aging and preclinical AD. Methods 71 apolipoprotein E (APOE) e4 homozygotes (HMZ), 194 e3/4 heterozygotes (HTZ), and 356 e4 noncarriers (NC) aged 21–87 years who were cognitively healthy underwent neuropsychological testing every two years. Longitudinal trajectories of test scores were compared between APOE subgroups. Results There was a significant effect of age on all cognitive domains in both APOE e4 carriers and NC. A significant effect of APOE e4 gene dose was confined to the memory domain and the Dementia Rating Scale. Cross sectional comparisons did not discriminate the groups. Conclusions While cognitive aging patterns are similar in APOE e4 carriers and NC, preclinical AD is characterized by a significant e4 gene dose effect that impacts memory and is detectable longitudinally. Preclinical neuropsychological testing strategies should emphasize memory sensitive measures and longitudinal design. PMID:23541188

The neuropsychology of normal aging and preclinical Alzheimer's disease.

PubMed

Caselli, Richard J; Locke, Dona E C; Dueck, Amylou C; Knopman, David S; Woodruff, Bryan K; Hoffman-Snyder, Charlene; Rademakers, Rosa; Fleisher, Adam S; Reiman, Eric M

2014-01-01

A National Institute on Aging-sponsored work group on preclinical Alzheimer's disease (AD) articulated the need to characterize cognitive differences between normal aging and preclinical AD. Seventy-one apolipoprotein E (APOE) ε4 homozygotes, 194 ε3/ε4 heterozygotes, and 356 ε4 noncarriers age 21 to 87 years who were cognitively healthy underwent neuropsychological testing every 2 years. Longitudinal trajectories of test scores were compared between APOE subgroups. There was a significant effect of age on all cognitive domains in both APOE ε4 carriers and noncarriers. A significant effect of APOE ε4 gene dose was confined to the memory domain and the Dementia Rating Scale. Cross-sectional comparisons did not discriminate the groups. Although cognitive aging patterns are similar in APOE ε4 carriers and noncarriers, preclinical AD is characterized by a significant ε4 gene dose effect that impacts memory and is detectable longitudinally. Preclinical neuropsychological testing strategies should emphasize memory-sensitive measures and longitudinal design. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Mechanism-based risk assessment strategy for drug-induced cholestasis using the transcriptional benchmark dose derived by toxicogenomics.

PubMed

Kawamoto, Taisuke; Ito, Yuichi; Morita, Osamu; Honda, Hiroshi

2017-01-01

Cholestasis is one of the major causes of drug-induced liver injury (DILI), which can result in withdrawal of approved drugs from the market. Early identification of cholestatic drugs is difficult due to the complex mechanisms involved. In order to develop a strategy for mechanism-based risk assessment of cholestatic drugs, we analyzed gene expression data obtained from the livers of rats that had been orally administered with 12 known cholestatic compounds repeatedly for 28 days at three dose levels. Qualitative analyses were performed using two statistical approaches (hierarchical clustering and principle component analysis), in addition to pathway analysis. The transcriptional benchmark dose (tBMD) and tBMD 95% lower limit (tBMDL) were used for quantitative analyses, which revealed three compound sub-groups that produced different types of differential gene expression; these groups of genes were mainly involved in inflammation, cholesterol biosynthesis, and oxidative stress. Furthermore, the tBMDL values for each test compound were in good agreement with the relevant no observed adverse effect level. These results indicate that our novel strategy for drug safety evaluation using mechanism-based classification and tBMDL would facilitate the application of toxicogenomics for risk assessment of cholestatic DILI.

DOSE: an R/Bioconductor package for disease ontology semantic and enrichment analysis.

PubMed

Yu, Guangchuang; Wang, Li-Gen; Yan, Guang-Rong; He, Qing-Yu

2015-02-15

Disease ontology (DO) annotates human genes in the context of disease. DO is important annotation in translating molecular findings from high-throughput data to clinical relevance. DOSE is an R package providing semantic similarity computations among DO terms and genes which allows biologists to explore the similarities of diseases and of gene functions in disease perspective. Enrichment analyses including hypergeometric model and gene set enrichment analysis are also implemented to support discovering disease associations of high-throughput biological data. This allows biologists to verify disease relevance in a biological experiment and identify unexpected disease associations. Comparison among gene clusters is also supported. DOSE is released under Artistic-2.0 License. The source code and documents are freely available through Bioconductor (http://www.bioconductor.org/packages/release/bioc/html/DOSE.html). Supplementary data are available at Bioinformatics online. gcyu@connect.hku.hk or tqyhe@jnu.edu.cn. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Toxicogenomic analysis identifies the apoptotic pathway as the main cause of hepatotoxicity induced by tributyltin.

PubMed

Zhou, Mi; Feng, Mei; Fu, Ling-Ling; Ji, Lin-Dan; Zhao, Jin-Shun; Xu, Jin

2016-11-01

Tributyltin (TBT) is one of the most widely used organotin biocides, which has severe endocrine-disrupting effects on marine species and mammals. Given that TBT accumulates at higher levels in the liver than in any other organ, and it acts mainly as a hepatotoxic agent, it is important to clearly delineate the hepatotoxicity of TBT. However, most of the available studies on TBT have focused on observations at the cellular level, while studies at the level of genes and proteins are limited; therefore, the molecular mechanisms of TBT-induced hepatotoxicity remains largely unclear. In the present study, we applied a toxicogenomic approach to investigate the effects of TBT on gene expression in the human normal liver cell line HL7702. Gene expression profiling identified the apoptotic pathway as the major cause of hepatotoxicity induced by TBT. Flow cytometry assays confirmed that medium- and high-dose TBT treatments significantly increased the number of apoptotic cells, and more cells underwent late apoptosis in the high-dose TBT group. The genes encoding heat shock proteins (HSPs), kinases and tumor necrosis factor receptors mediated TBT-induced apoptosis. These findings revealed novel molecular mechanisms of TBT-induced hepatotoxicity, and the current microarray data may also provide clues for future studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Carbon ion irradiation of the human prostate cancer cell line PC3: A whole genome microarray study

PubMed Central

SUETENS, ANNELIES; MOREELS, MARJAN; QUINTENS, ROEL; CHIRIOTTI, SABINA; TABURY, KEVIN; MICHAUX, ARLETTE; GRÉGOIRE, VINCENT; BAATOUT, SARAH

2014-01-01

Hadrontherapy is a form of external radiation therapy, which uses beams of charged particles such as carbon ions. Compared to conventional radiotherapy with photons, the main advantage of carbon ion therapy is the precise dose localization along with an increased biological effectiveness. The first results obtained from prostate cancer patients treated with carbon ion therapy showed good local tumor control and survival rates. In view of this advanced treatment modality we investigated the effects of irradiation with different beam qualities on gene expression changes in the PC3 prostate adenocarcinoma cell line. For this purpose, PC3 cells were irradiated with various doses (0.0, 0.5 and 2.0 Gy) of carbon ions (LET=33.7 keV/μm) at the beam of the Grand Accélérateur National d’Ions Lourds (Caen, France). Comparative experiments with X-rays were performed at the Belgian Nuclear Research Centre. Genome-wide gene expression was analyzed using microarrays. Our results show a downregulation in many genes involved in cell cycle and cell organization processes after 2.0 Gy irradiation. This effect was more pronounced after carbon ion irradiation compared with X-rays. Furthermore, we found a significant downregulation of many genes related to cell motility. Several of these changes were confirmed using qPCR. In addition, recurrence-free survival analysis of prostate cancer patients based on one of these motility genes (FN1) revealed that patients with low expression levels had a prolonged recurrence-free survival time, indicating that this gene may be a potential prognostic biomarker for prostate cancer. Understanding how different radiation qualities affect the cellular behavior of prostate cancer cells is important to improve the clinical outcome of cancer radiation therapy. PMID:24504141

Effects of Histone Deacetylase Inhibitor Panobinostat (LBH589) on Bone Marrow Mononuclear Cells of Relapsed or Refractory Multiple Myeloma Patients and Its Mechanisms

PubMed Central

Ma, Yanping; Liu, Wenhua; Zhang, Ling; Jia, Gu

2017-01-01

Background The aim of this study was to explore the impact of LBH589 alone or in combination with proteasome inhibitor bortezomib on multiple myeloma (MM) cell proliferation and its mechanism. Material/Methods MM cell line U266 and RRMM-BMMNC were treated with different concentrations of LBH589 alone or in combination with bortezomib. Cell proliferation was detected by MTT assay. Cell cycle and apoptosis was analyzed by flow cytometry. The protein and mRNA level of related genes was determined by Western blotting and qRT-PCR respectively. Results U266 cell and RRMM-BMMNC proliferation were inhibited by different concentrations of LBH589 (0, 10, 20, and 50 nmol/L) alone or 50 nmol/L of LBH589 in combination with bortezomib (10 and 20 nmol/L) in a dose- and time-dependent manner. LBH589 significantly induced G0/G1phase arrest and apoptosis in RRMM-BMMNC in a dose-dependent manner. The effects were significantly higher in all combined groups than in single-agent groups (all P<0.05). The mRNA level of Caspase3 and APAF1 were up-regulated gradually, while TOSO gene expression in RRMM-BMMNC was down-regulated gradually in a dose- and time-dependent manner. Moreover, LBH589 significantly induced hyperacetylation of histone H4, the protein level of PARP notably increased, and the level of Bcl-X decreased. Conclusions LBH589 can inhibit MM cell growth, block the cell cycle, and induce cell apoptosis, which has an anti-resistant effect on multidrug-resistant cells. LBH589 in combination with bortezomib has a synergistic effect on myeloma cells; its mechanism and reversal of drug resistance mechanism is involved in multiple changes in gene expression. PMID:29080899

DNA sensors to assess the effect of VKORC1 and CYP2C9 gene polymorphisms on warfarin dose requirement in Chinese patients with atrial fibrillation.

PubMed

Huang, Tao-Sheng; Zhang, Ling; He, Qiong; Li, Yu-Bin; Dai, Zhong-Li; Zheng, Jian-Rui; Cheng, Pei-Qi; He, Yun-Shao

2017-03-01

The optimal dose of warfarin depends on polymorphisms in the VKORC1 (the vitamin K epoxide reductase complex subunit (1) and CYP2C9 (cytochrome P450 2C9) genes. To minimize the risk of adverse reactions, warfarin dosages should be adjusted according to results from rapid and simple monitoring methods. However, there are few pharmacogenetic-guided warfarin dosing algorithms that are based on large cohorts from the Chinese population, especially patients with atrial fibrillation. This study aimed to validate a pharmacogenetic-guided warfarin dosing algorithm based on results from a new rapid electrochemical detection method used in a multicenter study. Three SNPs (CYP2C9 *2, *3 and VKORC1 c.-1639G > A) were genotyped by electrochemical detection using a sandwich-type format that included a 3' short thiol capture probe and a 5' ferrocene-labeled signal probe. A total of 1285 samples from four clinical hospitals were evaluated. Concordance rates between the results from the electrochemical DNA biosensor and the sequencing test were 99.8%. The results for gene distribution showed that most Chinese patients had higher warfarin susceptibility because mutant-type and heterozygotes were present in the majority of subjects (99.4%) at locus c.-1639G > A. When the International Warfarin Pharmacogenetics Consortium algorithm was used to estimate therapeutic dosages for 362 patients with AF and the values were compared with their actual dosages, the results revealed that 56.9% were similar to actual dosages (within the 20% range). A novel electrochemical detection method of CYP2C9 *2, *3and VKORC1 c.-1639G > A alleles was evaluated. The warfarin dosing algorithm based on data gathered from a large patient cohort can facilitate the reasonable and effective use of warfarin in Chinese patients with AF.

Sulforaphane, a cancer chemopreventive agent, induces pathways associated with membrane biosynthesis in response to tissue damage by aflatoxin B{sub 1}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Techapiesancharoenkij, Nirachara; Fiala, Jeannette L.A.; Navasumrit, Panida

Aflatoxin B{sub 1} (AFB{sub 1}) is one of the major risk factors for liver cancer globally. A recent study showed that sulforaphane (SF), a potent inducer of phase II enzymes that occurs naturally in widely consumed vegetables, effectively induces hepatic glutathione S-transferases (GSTs) and reduces levels of hepatic AFB{sub 1}-DNA adducts in AFB{sub 1}-exposed Sprague Dawley rats. The present study characterized the effects of SF pre-treatment on global gene expression in the livers of similarly treated male rats. Combined treatment with AFB{sub 1} and SF caused reprogramming of a network of genes involved in signal transduction and transcription. Changes inmore » gene regulation were observable 4 h after AFB{sub 1} administration in SF-pretreated animals and may reflect regeneration of cells in the wake of AFB{sub 1}-induced hepatotoxicity. At 24 h after AFB{sub 1} administration, significant induction of genes that play roles in cellular lipid metabolism and acetyl-CoA biosynthesis was detected in SF-pretreated AFB{sub 1}-dosed rats. Induction of this group of genes may indicate a metabolic shift toward glycolysis and fatty acid synthesis to generate and maintain pools of intermediate molecules required for tissue repair, cell growth and compensatory hepatic cell proliferation. Collectively, gene expression data from this study provide insights into molecular mechanisms underlying the protective effects of SF against AFB{sub 1} hepatotoxicity and hepatocarcinogenicity, in addition to the chemopreventive activity of this compound as a GST inducer. - Highlights: • This study revealed sulforaphane (SF)-deregulated gene sets in aflatoxin B{sub 1} (AFB{sub 1})-treated rat livers. • SF redirects biochemical networks toward lipid biosynthesis in AFB{sub 1}-dosed rats. • SF enhanced gene sets that would be expected to favor cell repair and regeneration.« less

Incensole acetate reduces depressive-like behavior and modulates hippocampal BDNF and CRF expression of submissive animals.

PubMed

Moussaieff, Arieh; Gross, Moshe; Nesher, Elimelech; Tikhonov, Tatiana; Yadid, Gal; Pinhasov, Albert

2012-12-01

Incensole acetate (IA), a constituent of Boswellia resin ('frankincense'), was previously demonstrated to exhibit an antidepressive-like effect in the Forced Swim Test (FST) in mice following single dose administration (50 mg/kg). Here, we show that acute administration of considerably lower dose (10 mg/kg) IA to selectively bred mice, showing prominent submissive behavior, exerted significant antidepressant-like effects in the FST. Furthermore, chronic administration of 1 or 5 mg/kg per day of IA for three consecutive weeks dose- and time-dependently reduced the submissiveness of the mice in the Dominant-Submissive Relationship test, developed to screen the chronic effect of antidepressants. This behavioral effect was concomitant to reduced serum corticosterone levels, dose-dependent down-regulation of corticotropin releasing factor and up-regulation of brain derived neurotrophic factor transcripts IV and VI expression in the hippocampus. These data suggest that IA modulates the hypothalamic-pituitary-adrenal (HPA) axis and influences hippocampal gene expression, leading to beneficial behavioral effects supporting its potential as a novel treatment of depressive-like disorders.

Final report for project "Effects of Low-Dose Irradiation on NFkB Signaling Networks and Mitochondria"

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woloschak, Gayle E; Grdina, David; Li, Jian-Jian

Low dose ionizing radiation effects are difficult to study in human population because of the numerous confounding factors such as genetic and lifestyle differences. Research in mammalian model systems and in vitro is generally used in order to overcome this difficulty. In this program project three projects have joined together to investigate effects of low doses of ionizing radiation. These are doses at and below 10 cGy of low linear energy transfer ionizing radiation such as X-ray and gamma rays. This project was focused on cellular signaling associated with nuclear factor kappa B (NFkB) and mitochondria - subcellular organelles criticalmore » for cell aging and aging-like changes induced by ionizing radiation. In addition to cells in culture this project utilized animal tissues accumulated in a radiation biology tissue archive housed at Northwestern University (http://janus.northwestern.edu/janus2/index.php). Major trust of Project 1 was to gather all of the DoE sponsored irradiated animal (mouse, rat and dog) data and tissues under one roof and investigate mitochondrial DNA changes and micro RNA changes in these samples. Through comparison of different samples we were trying to delineate mitochondrial DNA quantity alterations and micro RNA expression differences associated with different doses and dose rates of radiation. Historic animal irradiation experiments sponsored by DoE were done in several national laboratories and universities between 1950’s and 1990’s; while these experiments were closed data and tissues were released to Project 1. Project 2 used cells in culture to investigate effects that low doses or radiation have on NFκB and its target genes manganese superoxide dismutase (MnSOD) and genes involved in cell cycle: Cyclins (B1 and D1) and cyclin dependent kinases (CDKs). Project 3 used cells in culture such as “normal” human cells (breast epithelial cell line MCF10A cells and skin keratinocyte cells HK18) and mouse embryo fibroblast (mef) cells to focus on role of NFkB protein and several other proteins such as survivin (BIRC5) in radiation dependent regulation of tumor necrosis factor alpha (TNFα) and its downstream signaling.« less

Role of alpha2C-adrenoceptor subtype in spatial working memory as revealed by mice with targeted disruption of the alpha2C-adrenoceptor gene.

PubMed

Tanila, H; Mustonen, K; Sallinen, J; Scheinin, M; Riekkinen, P

1999-02-01

The role of the alpha2C-adrenoceptor subtype in mediating the beneficial effect of alpha2-adrenoceptor agonists on spatial working memory was studied in adult mice with targeted inactivation of the alpha2C-receptor gene (KO) and their wild-type controls (WT). A delayed alternation task was run in a T-maze with mixed delays varying from 20 s to 120 s. Dexmedetomidine, a specific but subtype nonselective alpha2-adrenoceptor agonist, dose-dependently decreased the total number of errors. The effect was strongest at the dose of 5 microg/kg (s.c.), and was observed similarly in KO and WT mice. KO mice performed inferior to WT mice due to a higher number of perseverative errors. Dexmedetomidine slowed initiation of the motor response in the start phase at lower doses in WT mice than in KO mice but no such difference was observed in the return phase of the task, suggesting involvement of alpha2C-adrenoceptors in the cognitive aspect of response preparation or in response sequence initiation. According to these findings, enhancement of spatial working memory is best achieved with alpha2-adrenoceptor agonists which have neither agonistic nor antagonistic effects at the alpha2C-adrenoceptor subtype.

Effect of Genetic Variants, Especially CYP2C9 and VKORC1, on the Pharmacology of Warfarin

PubMed Central

Fung, Erik; Patsopoulos, Nikolaos A.; Belknap, Steven M.; O’Rourke, Daniel J.; Robb, John F.; Anderson, Jeffrey L.; Shworak, Nicholas W.; Moore, Jason H.

2014-01-01

The genes encoding the cytochrome P450 2C9 enzyme (CYP2C9) and vitamin K-epoxide reductase complex unit 1 (VKORC1) are major determinants of anticoagulant response to warfarin. Together with patient demographics and clinical information, they account for approximately one-half of the warfarin dose variance in individuals of European descent. Recent prospective and randomized controlled trial data support pharmacogenetic guidance with their use in warfarin dose initiation and titration. Benefits from pharmacogenetics-guided warfarin dosing have been reported to extend beyond the period of initial dosing, with supportive data indicating benefits to at least 3 months. The genetic effects of VKORC1 and CYP2C9 in African and Asian populations are concordant with those in individuals of European ancestry; however, frequency distribution of allelic variants can vary considerably between major populations. Future randomized controlled trials in multiethnic settings using population-specific dosing algorithms will allow us to further ascertain the generalizability and cost-effectiveness of pharmacogenetics-guided warfarin therapy. Additional genome-wide association studies may help us to improve and refine dosing algorithms and potentially identify novel biological pathways. PMID:23041981

Inactivation of antibiotic resistance genes in municipal wastewater by chlorination, ultraviolet, and ozonation disinfection.

PubMed

Zhuang, Yao; Ren, Hongqiang; Geng, Jinju; Zhang, Yingying; Zhang, Yan; Ding, Lili; Xu, Ke

2015-05-01

This study investigated the inactivation of two antibiotic resistance genes (ARGs)-sul1 and tetG, and the integrase gene of class 1 integrons-intI1 by chlorination, ultraviolet (UV), and ozonation disinfection. Inactivation of sul1, tetG, and intI1 underwent increased doses of three disinfectors, and chlorine disinfection achieved more inactivation of ARGs and intI1 genes (chlorine dose of 160 mg/L with contact time of 120 min for 2.98-3.24 log reductions of ARGs) than UV irradiation (UV dose of 12,477 mJ/cm(2) for 2.48-2.74 log reductions of ARGs) and ozonation disinfection (ozonation dose of 177.6 mg/L for 1.68-2.55 log reductions of ARGs). The 16S rDNA was more efficiently removed than ARGs by ozone disinfection. The relative abundance of selected genes (normalized to 16S rDNA) increased during ozonation and with low doses of UV and chlorine disinfection. Inactivation of sul1 and tetG showed strong positive correlations with the inactivation of intI1 genes (for sul1, R (2)  = 0.929 with p < 0.01; for tetG, R (2)  = 0.885 with p < 0.01). Compared to other technologies (ultraviolet disinfection, ozonation disinfection, Fenton oxidation, and coagulation), chlorination is an alternative method to remove ARGs from wastewater effluents. At a chlorine dose of 40 mg/L with 60 min contact time, the selected genes inactivation efficiency could reach 1.65-2.28 log, and the cost was estimated at 0.041 yuan/m(3).

Polymorphisms in the Vitamin A Receptor and Innate Immunity Genes Influence the Antibody Response to Rubella Vaccination

PubMed Central

Ovsyannikova, Inna G.; Haralambieva, Iana H.; Dhiman, Neelam; O’Byrne, Megan M.; Pankratz, V. Shane; Jacobson, Robert M.; Poland, Gregory A.

2009-01-01

Background Genetic polymorphisms play an important role in rubella vaccine-induced immunity. Methods We genotyped 714 healthy children after two age-appropriate doses of rubella-containing vaccine for 142 potential SNPs. Results Specific polymorphisms in the vitamin A receptor, RIG-I, TRIM5 and TRIM22 genes were significantly associated with rubella vaccine humoral immunity. The minor allele of the rs4416353 in the vitamin A receptor gene was associated with an allele dose-related decrease (P=.019) in rubella antibody response. The minor allele of rs6793694, in the vitamin A receptor gene, was associated with an allele dose-related antibody decrease (P=.039). The minor variant of nonsynonymous SNP rs10813831 (Arg7Cys) in the RIG-I gene was associated with an allele dose-related decrease in rubella antibody level from 37.4 IU/mL to 28.0 IU/mL (P=.035), while increased representation of the minor allele of the 5’UTR SNP (rs3824949, P=.015), in the antiretroviral TRIM5 gene, was associated with an allele dose-related increase in rubella antibody. It is of particular interest that the nonsynonymous SNP rs3740996 (His43Tyr) in the TRIM5 gene was associated with variations in rubella antibody response (P=.016) after having been previously found to have a significant functional role. Conclusions These findings further expand our immunogenetic understanding of mechanisms of rubella vaccine-induced immunity. PMID:20001730

Green tea (Camellia sinensis) administration induces expression of immune relevant genes and biochemical parameters in rainbow trout (Oncorhynchus mykiss).

PubMed

Nootash, Shahab; Sheikhzadeh, Najmeh; Baradaran, Behzad; Oushani, Ali Khani; Maleki Moghadam, Mohammad Reza; Nofouzi, Katayoon; Monfaredan, Amir; Aghebati, Leili; Zare, Fatemeh; Shabanzadeh, Sadigheh

2013-12-01

Present study elucidates the efficacy of green tea (Camellia sinensis) on growth performance, immune and antioxidant systems and cytokine gene expression in rainbow trout tissues. Green tea was supplemented at 20, 100, and 500 mg kg(-1) diet and fed to fish (average weight: 23.5 g) for 35 days. No remarkable changes in growth performance were observed among all test groups. Lower lipid peroxidation product and higher superoxide dismutase activity were noted in fish received the medium dose of green tea. Significant increase in serum bactericidal activity and total protein were recorded in all treatment groups. All doses of green tea up-regulated Interleukin-1β transcription in the spleen, while Interleukin-1β mRNA level decreased significantly in the kidney of low dose of green tea. Interleukin-6 mRNA level was up-regulated in the spleen of high dose of green tea and liver of middle and high doses of green tea. High dose and medium dose of green tea up-regulated the interleukin-8 transcription in the kidney and liver, respectively. Meanwhile, green tea inhibited the production of interleukin-10 in all treatment groups compared with control group. Medium dose of green tea up-regulated tumor necrosis factor-α transcription in all fish tissues, while high dose and low dose of green tea enhanced tumor necrosis factor-α mRNA levels in the kidney and spleen, respectively. Present study suggests that green tea especially at 100 mg kg(-1) feed may effectively enhance the antioxidant system and immune system in rainbow trout. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of VKORC1 Genetic Polymorphisms on Warfarin Maintenance Dose Requirement in a Chinese Han Population

PubMed Central

Yan, Xiaojuan; Yang, Feng; Zhou, Hanyun; Zhang, Hongshen; Liu, Jianfei; Ma, Kezhong; Li, Yi; Zhu, Jun; Ding, Jianqiang

2015-01-01

Background VKORC1 is reported to be capable of treating several diseases with thrombotic risk, such as cardiac valve replacement. Some single-nucleotide polymorphisms (SNPs) in VKORC1 are documented to be associated with clinical differences in warfarin maintenance dose. This study explored the correlations of VKORC1–1639 G/A, 1173 C/T and 497 T/G genetic polymorphisms with warfarin maintenance dose requirement in patients undergoing cardiac valve replacement. Material/Methods A total of 298 patients undergoing cardiac valve replacement were recruited. During follow-up, clinical data were recorded. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was applied to detect VKORC1–1639 G/A, 1173 C/T and 497 T/G polymorphisms, and genotypes were analyzed. Results Correlations between warfarin maintenance dose and baseline characteristics revealed statistical significances of age, gender and operation methods with warfarin maintenance dose (all P<0.05). Warfarin maintenance dose in VKORC1–1639 G/A AG + GG carriers was obviously higher than in AA carriers (P<0.001). As compared with patients with TT genotype in VKORC1 1173 C/T, warfarin maintenance dose was apparently higher in patients with CT genotype (P<0.001). Linear regression analysis revealed that gender, operation method, method for heart valve replacement, as well as VKORC1–1639 G/A and 1173 C/T gene polymorphisms were significantly related to warfarin maintenance dose (all P<0.05). Conclusions VKORC1 gene polymorphisms are key genetic factors to affect individual differences in warfarin maintenance dose in patients undergoing cardiac valve replacement; meanwhile, gender, operation method and method for heart valve replacement might also be correlate with warfarin maintenance dose. PMID:26583785

Effects of intratracheally instilled laser printer-emitted engineered nanoparticles in a mouse model: A case study of toxicological implications from nanomaterials released during consumer use

PubMed Central

Pirela, Sandra V.; Lu, Xiaoyan; Miousse, Isabelle; Sisler, Jennifer D.; Qian, Yong; Guo, Nancy; Koturbash, Igor; Castranova, Vincent; Thomas, Treye; Godleski, John; Demokritou, Philip

2016-01-01

Incorporation of engineered nanomaterials (ENMs) into toners used in laser printers has led to countless quality and performance improvements. However, the release of ENMs during printing (consumer use) has raised concerns about their potential adverse health effects. The aim of this study was to use “real world” printer-emitted particles (PEPs), rather than raw toner powder, and assess the pulmonary responses following exposure by intratracheal instillation. Nine-week old male Balb/c mice were exposed to various doses of PEPs (0.5, 2.5 and 5 mg/kg body weight) by intratracheal instillation. These exposure doses are comparable to real world human inhalation exposures ranging from 13.7 to 141.9 h of printing. Toxicological parameters reflecting distinct mechanisms of action were evaluated, including lung membrane integrity, inflammation and regulation of DNA methylation patterns. Results from this in vivo toxicological analysis showed that while intratracheal instillation of PEPs caused no changes in the lung membrane integrity, there was a pulmonary immune response, indicated by an elevation in neutrophil and macrophage percentage over the vehicle control and low dose PEPs groups. Additionally, exposure to PEPs upregulated expression of the Ccl5 (Rantes), Nos1 and Ucp2 genes in the murine lung tissue and modified components of the DNA methylation machinery (Dnmt3a) and expression of transposable element (TE) LINE-1 compared to the control group. These genes are involved in both the repair process from oxidative damage and the initiation of immune responses to foreign pathogens. The results are in agreement with findings from previous in vitro cellular studies and suggest that PEPs may cause immune responses in addition to modifications in gene expression in the murine lung at doses that can be comparable to real world exposure scenarios, thereby raising concerns of deleterious health effects. PMID:26989787

Epigenetic influences of low-dose bisphenol A in primary human breast epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weng, Yu-I; Hsu, Pei-Yin; Liyanarachchi, Sandya

Substantial evidence indicates that exposure to bisphenol A (BPA) during early development may increase breast cancer risk later in life. The changes may persist into puberty and adulthood, suggesting an epigenetic process being imposed in differentiated breast epithelial cells. The molecular mechanisms by which early memory of BPA exposure is imprinted in breast progenitor cells and then passed onto their epithelial progeny are not well understood. The aim of this study was to examine epigenetic changes in breast epithelial cells treated with low-dose BPA. We also investigated the effect of BPA on the ER{alpha} signaling pathway and global gene expressionmore » profiles. Compared to control cells, nuclear internalization of ER{alpha} was observed in epithelial cells preexposed to BPA. We identified 170 genes with similar expression changes in response to BPA. Functional analysis confirms that gene suppression was mediated in part through an ER{alpha}-dependent pathway. As a result of exposure to BPA or other estrogen-like chemicals, the expression of lysosomal-associated membrane protein 3 (LAMP3) became epigenetically silenced in breast epithelial cells. Furthermore, increased DNA methylation in the LAMP3 CpG island was this repressive mark preferentially occurred in ER{alpha}-positive breast tumors. These results suggest that the in vitro system developed in our laboratory is a valuable tool for exposure studies of BPA and other xenoestrogens in human cells. Individual and geographical differences may contribute to altered patterns of gene expression and DNA methylation in susceptible loci. Combination of our exposure model with epigenetic analysis and other biochemical assays can give insight into the heritable effect of low-dose BPA in human cells.« less

Mechanisms Underlying Testicular Damage and Dysfunction in Mice With Partial IGF-1 Deficiency and the Effectiveness of IGF-1 Replacement Therapy.

PubMed

Castilla-Cortázar, Inma; Gago, Alberto; Muñoz, Úrsula; Ávila-Gallego, Elena; Guerra-Menéndez, Lucía; Sádaba, María Cruz; García-Magariño, Mariano; Olleros Santos-Ruiz, María; Aguirre, G A; Puche, Juan Enrique

2015-12-01

To determine whether insulin-like growth factor (IGF-1) deficiency can cause testicular damage and to examine changes of the testicular morphology and testicular function-related gene expression caused by IGF-1 deficiency. Therefore, this study aims to determine the benefits of low doses of IGF-1 and to explore the mechanisms underlying the IGF-1 replacement therapy. A murine model of IGF-1 deficiency was used to avoid any factor that could contribute to testicular damage. Testicular weight, score of histopathological damage, and gene expressions were studied in 3 experimental groups of mice: controls (wild-type Igf1(+/+)), heterozygous Igf1(+/-) with partial IGF-1 deficiency, and heterozygous Igf1(+/-) treated with IGF-1. Results show that the partial IGF-1 deficiency induced testicular damage and altered expression of genes involved in IGF-1 and growth hormone signaling and regulation, testicular hormonal function, extracellular matrix establishment and its regulation, angiogenesis, fibrogenesis, inflammation, and cytoprotection. In addition, proteins involved in tight junction expression were found to be reduced. However, low doses of IGF-1 restored the testicular damage and most of these parameters. IGF-1 deficiency caused the damage of the blood-testis barrier and testicular structure and induced the abnormal testicular function-related gene expressions. However, low doses of IGF-1 constitute an effective replacement therapy that restores the described testicular damage. Data herein show that (1) cytoprotective activities of IGF-1 seem to be mediated by heat shock proteins and that (2) connective tissue growth factor could play a relevant role together with IGF-1 in the extracellular matrix establishment. Copyright © 2015 Elsevier Inc. All rights reserved.

Pharmacogenetics of tacrolimus and sirolimus in renal transplant patients: from retrospective analyses to prospective studies.

PubMed

Anglicheau, D; Legendre, C; Thervet, E

2007-09-01

The promises of pharmacogenetics are to elucidate the inherited basis of differences between individual responses to drugs in order to identify the right drug and dose for each patient. The recent identification of genetic polymorphisms in drug-metabolizing enzymes and drug transporters led to the hypothesis that genetic factors may be implicated in the interindividual variability of the pharmacokinetic or pharmacodynamic characteristics of immunosuppressive drugs, major side effects, and efficacy. The purpose of this study was to provide a short overview of recent results obtained in the field of pharmacogenetics of tacrolimus and sirolimus, both substrates of the cytochrome P450 3A (CYP3A) enzymes and of the efflux pump P-glycoprotein, the product of the Multidrug Resistance-1 (MDR1) genes. A number of retrospective studies that demonstrated a link between the polymorphisms governing the CYP3A5 protein expression, with more conflicting results with the MDR1 gene polymorphisms, related to the daily dose necessary to achieve adequate blood tacrolimus levels. The CYP3A5 polymorphisms have also been associated with sirolimus pharmacokinetics. One challenge is to investigate the combined effect of a number of different polymorphisms in various genes to define genetic backgrounds with different pharmacokinetic profiles using high throughput technologies. Another challenge is to move toward prospective randomized studies to explore whether a pharmacogenetic approach, taking into account a limited number of polymorphisms prior to drug treatment, could be used on an individual basis to guide initial dosing of a given drug. The last challenge is based on "target" pharmacogenetics to investigate the role of the polymorphisms of other genes implicated in the efficacy and/or safety of the drug.

Systemic SMAD7 Gene Therapy Increases Striated Muscle Mass and Enhances Exercise Capacity in a Dose-Dependent Manner.

PubMed

Maricelli, Joseph W; Bishaw, Yemeserach M; Wang, Bo; Du, Min; Rodgers, Buel D

2018-03-01

Striated muscle wasting occurs with a variety of disease indications, contributing to mortality and compromising life quality. Recent studies indicate that the recombinant adeno-associated virus (serotype 6) Smad7 gene therapeutic, AVGN7, enhances skeletal and cardiac muscle mass and prevents cancer-induced wasting of both tissues. This is accomplished by attenuating ActRIIb intracellular signaling and, as a result, the physiological actions of myostatin and other ActRIIb ligands. AVGN7 also enhances isolated skeletal muscle twitch force, but is unknown to improve systemic muscle function similarly, especially exercise capacity. A 2-month-long dose-escalation study was therefore conducted using 5 × 10 11 , 1 × 10 12 , and 5 × 10 12 vg/mouse and different tests of systemic muscle function. Body mass, skeletal muscle mass, heart mass, and forelimb grip strength were all increased in a dose-dependent manner, as was the fiber cross-sectional area of tibialis anterior muscles. Maximal oxygen consumption (VO 2 max), a measure of metabolic rate, was similarly enhanced during forced treadmill running, and although the total distance traveled was only elevated by the highest dose, all doses reduced the energy expenditure rate compared to control mice injected with an empty vector. Such improvements in VO 2 max are consistent with physiological cardiac hypertrophy, which is highly beneficial and a normal adaptive response to exercise. This was particularly evident at the lowest dose tested, which had minimal significant effects on skeletal muscle mass and/or function, but increased heart weight and exercise capacity. These results together suggest that AVGN7 enhances striated muscle mass and systemic muscle function. They also define minimally effective and optimal doses for future preclinical trials and toxicology studies and in turn will aid in establishing dose ranges for clinical trials.

The relation between doses or post-plasma time points and apoptosis of leukemia cells induced by dielectric barrier discharge plasma

NASA Astrophysics Data System (ADS)

Wang, Chao; Zhang, Haixia; Xue, Zhixiao; Yin, Huijuan; Niu, Qing; Chen, Hongli

2015-12-01

The dielectric barrier discharge (DBD) plasma was applied to induce apoptosis of LT-12 leukemia cells. Plasma effects on cell death was evaluated by MTT assay and FCM apoptosis assay with Annexin V/PI double staining, suggesting that plasma killing cells rate and inducing cell apoptosis rate both positively were related to the plasma doses or the post-plasma time points. The cell death rates increased from 15.2% to 33.1% and the apoptosis rate raise from 23.8% to 28% when the dose raise from 60s to 120 s at 8 h post-plasma, while they increased from 15.4% to 34.9% and from 48% to 55.3% respectively at the same doses at 12 h post-plasma. Furthermore, the production of reactive oxygen species (ROS), gene and protein expression for Caspases and Bcl-2 family members were measured for exploring the related apoptotic mechanisms phenomenon. We found ROS immediately increased to 1.24 times of the original amount, then increasing to 5.39-fold at 20 h after treatment. The gene and protein expression for Caspases and Bcl-2 family members are very active at 8-12 h post-plasma. Our results demonstrate that DBD plasma can effectively induce tumor cell death through primarily related apoptotic mechanisms.

Protracted low-dose radiation priming and response of liver to acute gamma and proton radiation.

PubMed

Gridley, D S; Mao, X W; Cao, J D; Bayeta, E J M; Pecaut, M J

2013-10-01

This study evaluated liver from C57BL/6 mice irradiated with low-dose/low-dose-rate (LDR) γ-rays (0.01 Gy, 0.03 cGy/h), with and without subsequent exposure to acute 2 Gy gamma or proton radiation. Analyses were performed on day 56 post-exposure. Expression patterns of apoptosis-related genes were strikingly different among irradiated groups compared with 0 Gy (p < 0.05). Two genes were affected in the Gamma group, whereas 10 were modified in the LDR + Gamma group. In Proton and LDR + Proton groups, there were six and 12 affected genes, respectively. Expression of genes in the Gamma (Traf3) and Proton (Bak1, Birc2, Birc3, Mcl1) groups was no longer different from 0 Gy control group when mice were pre-exposed to LDR γ-rays. When each combined regimen was compared with the corresponding group that received acute radiation alone, two genes in the LDR + Gamma group and 17 genes in the LDR + Proton group were modified; greatest effect was on Birc2 and Nol3 (> 5-fold up-regulated by LDR + Protons). Oxygen radical production in livers from the LDR + Proton group was higher in LDR, Gamma, and LDR + Gamma groups (p < 0.05 vs. 0 Gy), but there were no differences in phagocytosis of E. coli. Sections stained with hematoxylin and eosin (H&E) suggested more inflammation, with and without necrosis, in some irradiated groups. The data demonstrate that response to acute radiation is dependent on radiation quality and regimen and that some LDR γ-ray-induced modifications in liver response were still evident nearly 2 months after exposure.

Antibiotic Administration Routes Significantly Influence the Levels of Antibiotic Resistance in Gut Microbiota

PubMed Central

Zhang, Lu; Huang, Ying; Zhou, Yang; Buckley, Timothy

2013-01-01

This study examined the impact of oral exposure to antibiotic-resistant bacteria and antibiotic administration methods on antibiotic resistance (AR) gene pools and the profile of resistant bacteria in host gastrointestinal (GI) tracts using C57BL/6J mice with natural gut microbiota. Mice inoculated with a mixture of tet(M)-carrying Enterococcus spp. or blaCMY-2-carrying Escherichia coli were treated with different doses of tetracycline hydrochloride (Tet) or ampicillin sodium (Amp) and delivered via either feed or intravenous (i.v.) injection. Quantitative PCR assessment of mouse fecal samples revealed that (i) AR gene pools were below the detection limit in mice without prior inoculation of AR gene carriers regardless of subsequent exposure to corresponding antibiotics; (ii) oral exposure to high doses of Tet and Amp in mice inoculated with AR gene carriers led to rapid enrichment of corresponding AR gene pools in feces; (iii) significantly less or delayed development of AR in the GI tract of the AR carrier-inoculated mice was observed when the same doses of antibiotics were administered via i.v. injection rather than oral administration; and (iv) antibiotic dosage, and maybe the excretion route, affected AR in the GI tract. The shift of dominant AR bacterial populations in the gut microbiota was consistent with the dynamics of AR gene pools. The emergence of endogenous resistant bacteria in the gut microbiota corresponding to drug exposure was also observed. Together, these data suggest that oral administration of antibiotics has a prominent effect on AR amplification and development in gut microbiota, which may be minimized by alternative drug administration approaches, as illustrated by i.v. injection in this study and proper drug selection. PMID:23689712

Differential gene expression patterns in developing sexually dimorphic rat brain regions exposed to antiandrogenic, estrogenic, or complex endocrine disruptor mixtures: glutamatergic synapses as target.

PubMed

Lichtensteiger, Walter; Bassetti-Gaille, Catherine; Faass, Oliver; Axelstad, Marta; Boberg, Julie; Christiansen, Sofie; Rehrauer, Hubert; Georgijevic, Jelena Kühn; Hass, Ulla; Kortenkamp, Andreas; Schlumpf, Margret

2015-04-01

The study addressed the question whether gene expression patterns induced by different mixtures of endocrine disrupting chemicals (EDCs) administered in a higher dose range, corresponding to 450×, 200×, and 100× high-end human exposure levels, could be characterized in developing brain with respect to endocrine activity of mixture components, and which developmental processes were preferentially targeted. Three EDC mixtures, A-Mix (anti-androgenic mixture) with 8 antiandrogenic chemicals (di-n-butylphthalate, diethylhexylphthalate, vinclozolin, prochloraz, procymidone, linuron, epoxiconazole, and DDE), E-Mix (estrogenic mixture) with 4 estrogenic chemicals (bisphenol A, 4-methylbenzylidene camphor, 2-ethylhexyl 4-methoxycinnamate, and butylparaben), a complex mixture, AEP-Mix, containing the components of A-Mix and E-Mix plus paracetamol, and paracetamol alone, were administered by oral gavage to rat dams from gestation day 7 until weaning. General developmental endpoints were not affected by EDC mixtures or paracetamol. Gene expression was analyzed on postnatal day 6, during sexual brain differentiation, by exon microarray in medial preoptic area in the high-dose group, and by real-time RT-PCR in medial preoptic area and ventromedial hypothalamus in all dose groups. Expression patterns were mixture, sex, and region specific. Effects of the analgesic drug paracetamol, which exhibits antiandrogenic activity in peripheral systems, differed from those of A-Mix. All mixtures had a strong, mixture-specific impact on genes encoding for components of excitatory glutamatergic synapses and genes controlling migration and pathfinding of glutamatergic and GABAergic neurons, as well as genes linked with increased risk of autism spectrum disorders. Because development of glutamatergic synapses is regulated by sex steroids also in hippocampus, this may represent a general target of ECD mixtures.

Intratumoral injection of INGN 241, a nonreplicating adenovector expressing the melanoma-differentiation associated gene-7 (mda-7/IL24): biologic outcome in advanced cancer patients.

PubMed

Tong, Alex W; Nemunaitis, John; Su, Dan; Zhang, Yuan; Cunningham, Casey; Senzer, Neil; Netto, George; Rich, Dawn; Mhashilkar, Abner; Parker, Karen; Coffee, Keith; Ramesh, Rajagopal; Ekmekcioglu, Suhendan; Grimm, Elizabeth A; van Wart Hood, Jill; Merritt, James; Chada, Sunil

2005-01-01

The mda-7 gene (approved gene symbol IL24) is a novel tumor suppressor gene with tumor-apoptotic and immune-activating properties. We completed a Phase I dose-escalation clinical trial, in which a nonreplicating adenoviral construct expressing the mda-7 transgene (INGN 241; Ad-mda7) was administered intratumorally to 22 patients with advanced cancer. Excised tumors were evaluated for vector-specific DNA and RNA, transgenic MDA-7 expression, and biological effects. Successful gene transfer as assessed by DNA- and RT-PCR was demonstrated in 100% of patients evaluated. DNA analyses demonstrated a dose-dependent penetration of INGN 241 (up to 4 x 10(8) copies/mug DNA at the 2 x 10(12) vp dose). A parallel distribution of vector DNA, vector RNA, MDA-7 protein expression, and apoptosis induction was observed in all tumors, with signals decreasing with distance away from the injection site. Additional evidence for bioactivity of INGN 241 was illustrated via regulation of the MDA-7 target genes beta-catenin, iNOS, and CD31. Transient increases (up to 20-fold) of serum IL-6, IL-10, and TNF-alpha were observed. Significantly higher elevations of IL-6 and TNF-alpha were observed in patients who responded clinically to INGN 241. Patients also showed marked increases of CD3+CD8+ T cells posttreatment, suggesting that INGN 241 increased systemic TH1 cytokine production and mobilized CD8+ T cells. Intratumoral delivery of INGN 241 induced apoptosis in a large volume of tumor and elicited tumor-regulatory and immune-activating events that are consistent with the preclinical features of MDA-7/IL-24.

Antibiotic administration routes significantly influence the levels of antibiotic resistance in gut microbiota.

PubMed

Zhang, Lu; Huang, Ying; Zhou, Yang; Buckley, Timothy; Wang, Hua H

2013-08-01

This study examined the impact of oral exposure to antibiotic-resistant bacteria and antibiotic administration methods on antibiotic resistance (AR) gene pools and the profile of resistant bacteria in host gastrointestinal (GI) tracts using C57BL/6J mice with natural gut microbiota. Mice inoculated with a mixture of tet(M)-carrying Enterococcus spp. or blaCMY-2-carrying Escherichia coli were treated with different doses of tetracycline hydrochloride (Tet) or ampicillin sodium (Amp) and delivered via either feed or intravenous (i.v.) injection. Quantitative PCR assessment of mouse fecal samples revealed that (i) AR gene pools were below the detection limit in mice without prior inoculation of AR gene carriers regardless of subsequent exposure to corresponding antibiotics; (ii) oral exposure to high doses of Tet and Amp in mice inoculated with AR gene carriers led to rapid enrichment of corresponding AR gene pools in feces; (iii) significantly less or delayed development of AR in the GI tract of the AR carrier-inoculated mice was observed when the same doses of antibiotics were administered via i.v. injection rather than oral administration; and (iv) antibiotic dosage, and maybe the excretion route, affected AR in the GI tract. The shift of dominant AR bacterial populations in the gut microbiota was consistent with the dynamics of AR gene pools. The emergence of endogenous resistant bacteria in the gut microbiota corresponding to drug exposure was also observed. Together, these data suggest that oral administration of antibiotics has a prominent effect on AR amplification and development in gut microbiota, which may be minimized by alternative drug administration approaches, as illustrated by i.v. injection in this study and proper drug selection.

Intravaginal gene silencing using biodegradable polymer nanoparticles densely loaded with small-interfering RNA

NASA Astrophysics Data System (ADS)

Woodrow, Kim A.; Cu, Yen; Booth, Carmen J.; Saucier-Sawyer, Jennifer K.; Wood, Monica J.; Mark Saltzman, W.

2009-06-01

Vaginal instillation of small-interfering RNA (siRNA) using liposomes has led to silencing of endogenous genes in the genital tract and protection against challenge from infectious disease. Although siRNA lipoplexes are easily formulated, several of the most effective transfection agents available commercially may be toxic to the mucosal epithelia and none are able to provide controlled or sustained release. Here, we demonstrate an alternative approach using nanoparticles composed entirely of FDA-approved materials. To render these materials effective for gene silencing, we developed novel approaches to load them with high amounts of siRNA. A single dose of siRNA-loaded nanoparticles to the mouse female reproductive tract caused efficient and sustained gene silencing. Knockdown of gene expression was observed proximal (in the vaginal lumen) and distal (in the uterine horns) to the site of topical delivery. In addition, nanoparticles penetrated deep into the epithelial tissue. This is the first report demonstrating that biodegradable polymer nanoparticles are effective delivery vehicles for siRNA to the vaginal mucosa.

Combined exposure to X-irradiation followed by N-ethyl-N-nitrosourea treatment alters the frequency and spectrum of Ikaros point mutations in murine T-cell lymphoma.

PubMed

Kakinuma, Shizuko; Nishimura, Mayumi; Amasaki, Yoshiko; Takada, Mayumi; Yamauchi, Kazumi; Sudo, Satomi; Shang, Yi; Doi, Kazutaka; Yoshinaga, Shinji; Shimada, Yoshiya

2012-09-01

Ionizing radiation is a well-known carcinogen, but its potency may be influenced by other environmental carcinogens, which is of practical importance in the assessment of risk. Data are scarce, however, on the combined effect of radiation with other environmental carcinogens and the underlying mechanisms involved. We studied the mode and mechanism of the carcinogenic effect of radiation in combination with N-ethyl-N-nitrosourea (ENU) using doses approximately equal to the corresponding thresholds. B6C3F1 mice exposed to fractionated X-irradiation (Kaplan's method) followed by ENU developed T-cell lymphomas in a dose-dependent manner. Radiation doses above an apparent threshold acted synergistically with ENU to promote lymphoma development, whereas radiation doses below that threshold antagonized lymphoma development. Ikaros, which regulates the commitment and differentiation of lymphoid lineage cells, is a critical tumor suppressor gene frequently altered in both human and mouse lymphomas and shows distinct mutation spectra between X-ray- and ENU-induced lymphomas. In the synergistically induced lymphomas, we observed a low frequency of LOH and an inordinate increase of Ikaros base substitutions characteristic of ENU-induced point mutations, G:C to A:T at non-CpG, A:T to G:C, G:C to T:A and A:T to T:A. This suggests that radiation doses above an apparent threshold activate the ENU mutagenic pathway. This is the first report on the carcinogenic mechanism elicited by combined exposure to carcinogens below and above threshold doses based on the mutation spectrum of the causative gene. These findings constitute a basis for assessing human cancer risk following exposure to multiple carcinogens. Copyright © 2012 Elsevier B.V. All rights reserved.

Inflammation-associated gene transcription and expression in mouse lungs induced by low molecular weight compounds from fungi from the built environment.

PubMed

Miller, J D; Sun, M; Gilyan, A; Roy, J; Rand, T G

2010-01-05

Few metabolites from fungi found indoors have been tested for inflammatory mediators endpoints in primary cultures of alveolar macrophages or in vivo. In this study, mice were intratracheally instilled with a single dose comprising 4x10(-5)moletoxin/kg lung wt dose of either atranone C, brevianamide, cladosporin, mycophenolic acid, neoechinulin A & B, sterigmatocystin or TMC-120A. These toxins are from fungi common on damp building materials. The dose used was comparable to the estimated doses of possible human exposure. Hematoxylin and eosin (H&E) histology and Alcian Blue/Periodic Acid Schiff (AB/PAS) histochemistry were used to evaluate lungs for time course (4h and 12h post-exposure (PE)) inflammatory and toxic changes. Reverse-transcription (RT)-PCR based arrays were also employed to evaluate time course inflammation-associated gene transcription in lung tissues of the different toxins. Immunohistochemistry (IHC) was used to probe MIP-2 and Tnf-alpha protein expression in treatment lungs to determine whether responses correspond with gene transcription data. Both histology and histochemistry revealed that toxin exposed lungs at 12h PE showed evidence of inflammation. H&E revealed that bronchioli were lined with irregularly thickened and sometimes sloughing epithelium and bronchiolar spaces supported infiltration of leukocytes, cellular and mucus-like debris while alveolar spaces supported swollen macrophages and modest amorphous debris accumulations. All toxin-instilled lungs exhibited copious mucus production and alveolar macrophages with red stained cytoplasm on bronchiolar surfaces, especially at 12h PE. Array analysis of 83 inflammation-associated genes extracted from lung tissue demonstrated a number of patterns, compared to controls. 82 genes assayed at 4h PE and 75 genes at 12h PE were significantly altered (p< or =0.05; >or =1.5-fold or < or =-1.5-fold change) in the different treatment animal groups. Expression of transcriptionally regulated genes was confirmed using immunohistochemistry that demonstrated MIP-2 and Tnf-alpha staining in respiratory bronchiolar epithelia, alveolar macrophages and alveolar type II cells. The transcriptional regulation in these genes in the treatment groups suggests that they may serve central roles in the immunomodulation of toxin-induced pro-inflammatory lung responses. Hierarchical cluster analysis revealed significant patterns of gene transcription linking the response of the toxins at equimolar doses in three groups: (1) brevianamide, mycophenolic acid and neoechinulin B, (2) neoechinulin A and sterigmatocystin, and (3) cladosporin, atranone C and TMC-120. The results further confirm the inflammatory nature of metabolites/toxins from such fungi can contribute to the development of non-allergenic respiratory health effects.

Effect of Temperature on Synthetic Positive and Negative Feedback Gene Networks

NASA Astrophysics Data System (ADS)

Charlebois, Daniel A.; Marshall, Sylvia; Balazsi, Gabor

Synthetic biological systems are built and tested under well controlled laboratory conditions. How altering the environment, such as the ambient temperature affects their function is not well understood. To address this question for synthetic gene networks with positive and negative feedback, we used mathematical modeling coupled with experiments in the budding yeast Saccharomyces cerevisiae. We found that cellular growth rates and gene expression dose responses change significantly at temperatures above and below the physiological optimum for yeast. Gene expression distributions for the negative feedback-based circuit changed from unimodal to bimodal at high temperature, while the bifurcation point of the positive feedback circuit shifted up with temperature. These results demonstrate that synthetic gene network function is context-dependent. Temperature effects should thus be tested and incorporated into their design and validation for real-world applications. NSERC Postdoctoral Fellowship (Grant No. PDF-453977-2014).

Genotoxicity of a Low-Dose Nitrosamine Mixture as Drinking Water Disinfection Byproducts in NIH3T3 Cells.

PubMed

Wang, Hai-Yan; Qin, Ming; Dong, Lei; Lv, Jia-Ying; Wang, Xia

2017-01-01

N - nitrosamines (NAms), which can arise as byproducts of disinfection agents, are reportedly found in drinking water, and their potential carcinogenicity is a concern; however, little research exists regarding the genotoxicity or carcinogenicity of NAms exposure as a low-dose mixture. The three most common NAms components in China's drinking water are N -nitrosodimethylamine (NDMA), N -nitrosodiethylamine (NDEA) and N -nitrosomethylethylamine (NMEA). Thus, we measured the genotoxic and carcinogenic potential of these compounds and measured the cell cycle and gene expression. The data show that exposure to the NAms-mixture doubled the revertants in the TA98 and TA100 S. typhimurium strains and increased the DNA double-strand breaks and the micronuclear frequency in the NIH3T3 cells compared to a single exposure. After long-term NAms mixture exposure, a malignant transformation of NIH3T3 and a significantly increased G2/M distribution were observed. Furthermore, P53, CDK1, P38, CDC25A and CyclinB expressions were down-regulated in the NAms-mixture exposure group; however, P21 and GADD45A genes were up-regulated. Interestingly, the CHK1/CHK2 and CDC25A genes had two responses, depending on the NAms concentrations. Thus, we observed mutagenic, genotoxic and carcinogenic effects after a low-dose NAms-mixture exposure in drinking water, and DNA repair and apoptosis pathways may contribute to these adverse effects.

Genotoxicity of a Low-Dose Nitrosamine Mixture as Drinking Water Disinfection Byproducts in NIH3T3 Cells

PubMed Central

Wang, Hai-yan; Qin, Ming; Dong, Lei; Lv, Jia-ying; Wang, Xia

2017-01-01

N-nitrosamines (NAms), which can arise as byproducts of disinfection agents, are reportedly found in drinking water, and their potential carcinogenicity is a concern; however, little research exists regarding the genotoxicity or carcinogenicity of NAms exposure as a low-dose mixture. The three most common NAms components in China's drinking water are N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA) and N-nitrosomethylethylamine (NMEA). Thus, we measured the genotoxic and carcinogenic potential of these compounds and measured the cell cycle and gene expression. The data show that exposure to the NAms-mixture doubled the revertants in the TA98 and TA100 S. typhimurium strains and increased the DNA double-strand breaks and the micronuclear frequency in the NIH3T3 cells compared to a single exposure. After long-term NAms mixture exposure, a malignant transformation of NIH3T3 and a significantly increased G2/M distribution were observed. Furthermore, P53, CDK1, P38, CDC25A and CyclinB expressions were down-regulated in the NAms-mixture exposure group; however, P21 and GADD45A genes were up-regulated. Interestingly, the CHK1/CHK2 and CDC25A genes had two responses, depending on the NAms concentrations. Thus, we observed mutagenic, genotoxic and carcinogenic effects after a low-dose NAms-mixture exposure in drinking water, and DNA repair and apoptosis pathways may contribute to these adverse effects. PMID:28924367

Non-equilibrium repressor binding kinetics link DNA damage dose to transcriptional timing within the SOS gene network.

PubMed

Culyba, Matthew J; Kubiak, Jeffrey M; Mo, Charlie Y; Goulian, Mark; Kohli, Rahul M

2018-06-01

Biochemical pathways are often genetically encoded as simple transcription regulation networks, where one transcription factor regulates the expression of multiple genes in a pathway. The relative timing of each promoter's activation and shut-off within the network can impact physiology. In the DNA damage repair pathway (known as the SOS response) of Escherichia coli, approximately 40 genes are regulated by the LexA repressor. After a DNA damaging event, LexA degradation triggers SOS gene transcription, which is temporally separated into subsets of 'early', 'middle', and 'late' genes. Although this feature plays an important role in regulating the SOS response, both the range of this separation and its underlying mechanism are not experimentally defined. Here we show that, at low doses of DNA damage, the timing of promoter activities is not separated. Instead, timing differences only emerge at higher levels of DNA damage and increase as a function of DNA damage dose. To understand mechanism, we derived a series of synthetic SOS gene promoters which vary in LexA-operator binding kinetics, but are otherwise identical, and then studied their activity over a large dose-range of DNA damage. In distinction to established models based on rapid equilibrium assumptions, the data best fit a kinetic model of repressor occupancy at promoters, where the drop in cellular LexA levels associated with higher doses of DNA damage leads to non-equilibrium binding kinetics of LexA at operators. Operators with slow LexA binding kinetics achieve their minimal occupancy state at later times than operators with fast binding kinetics, resulting in a time separation of peak promoter activity between genes. These data provide insight into this remarkable feature of the SOS pathway by demonstrating how a single transcription factor can be employed to control the relative timing of each gene's transcription as a function of stimulus dose.

Gene Expression Changes in Mouse Intestinal Tissue Following Whole-Body Proton or Gamma-Irradiation

NASA Technical Reports Server (NTRS)

Purgason, Ashley; Zhang, Ye; Mangala, Lingegowda; Nie, Ying; Gridley, Daila; Hamilton, Stanley R.; Seidel, Derek V.; Wu, Honglu

2014-01-01

Crew members face potential consequences following exposure to the space radiation environment including acute radiation syndrome and cancer. The space radiation environment is ample with protons, and numerous studies have been devoted to the understanding of the health consequences of proton exposures. In this project, C57BL/6 mice underwent whole-body exposure to 250 MeV of protons at doses of 0, 0.1, 0.5, 2 and 6 Gy and the gastrointestinal (GI) tract of each animal was dissected four hours post-irradiation. Standard H&E staining methods to screen for morphologic changes in the tissue showed an increase in apoptotic lesions for even the lowest dose of 0.1 Gy, and the percentage of apoptotic cells increased with increasing dose. Results of gene expression changes showed consistent up- or down- regulation, up to 10 fold, of a number of genes across exposure doses that may play a role in proton-induced oxidative stress including Gpx2. A separate study in C57BL/6 mice using the same four hour time point but whole-body gamma-irradiation showed damage to the small intestine with lesions appearing at the smallest dose of 0.05 Gy and increasing with increasing absorbed dose. Expressions of genes associated with oxidative stress processes were analyzed at four hours and twenty-four hours after exposure to gamma rays. We saw a much greater number of genes with significant up- or down-regulation twenty-four hours post-exposure as compared to the four hour time point. At both four hours and twenty-four hours post-exposure, Duox1 and Mpo underwent up-regulation for the highest dose of 6 Gy. Both protons and gamma rays lead to significant variation in gene expressions and these changes may provide insight into the mechanism of injury seen in the GI tract following radiation exposure. We have also completed experiments using a BALB/c mouse model undergoing whole-body exposure to protons. Doses of 0, 0.1, 1 and 2 Gy were used and results will be compared to the work mentioned above. The most striking result preliminarily is that both strains of mice show a greater number of genes changing at the lowest dose of exposure for their respective pathways.

Integrated analysis of genetic variation and gene expression reveals novel variant for increased warfarin dose requirement in African Americans.

PubMed

Hernandez, W; Gamazon, E R; Aquino-Michaels, K; Smithberger, E; O'Brien, T J; Harralson, A F; Tuck, M; Barbour, A; Cavallari, L H; Perera, M A

2017-04-01

Essentials Genetic variants controlling gene regulation have not been explored in pharmacogenomics. We tested liver expression quantitative trait loci for association with warfarin dose response. A novel predictor for increased warfarin dose response in African Americans was identified. Precision medicine must take into account population-specific variation in gene regulation. Background Warfarin is commonly used to control and prevent thromboembolic disorders. However, because of warfarin's complex dose-requirement relationship, safe and effective use is challenging. Pharmacogenomics-guided warfarin dosing algorithms that include the well-established VKORC1 and CYP2C9 polymorphisms explain only a small proportion of inter-individual variability in African Americans (AAs). Objectives We aimed to assess whether transcriptomic analyses could be used to identify regulatory variants associated with warfarin dose response in AAs. Patients/Methods We identified a total of 56 expression quantitative trait loci (eQTLs) for CYP2C9, VKORC1 and CALU derived from human livers and evaluated their association with warfarin dose response in two independent AA warfarin patient cohorts. Results We found that rs4889606, a strong cis-eQTL for VKORC1 (log 10 Bayes Factor = 12.02), is significantly associated with increased warfarin daily dose requirement (β = 1.1; 95% confidence interval [CI] 0.46 to 1.8) in the discovery cohort (n = 305) and in the replication cohort (β = 1.04; 95% CI 0.33 -1.7; n = 141) after conditioning on relevant covariates and the VKORC1 -1639G>A (rs9923231) variant. Inclusion of rs4889606 genotypes, along with CYP2C9 alleles, rs9923231 genotypes and clinical variables, explained 31% of the inter-patient variability in warfarin dose requirement. We demonstrate different linkage disequilibrium patterns in the region encompassing rs4889606 and rs9923231 between AAs and European Americans, which may explain the increased dose requirement found in AAs. Conclusion Our approach of interrogating eQTLs identified in liver has revealed a novel predictor of warfarin dose response in AAs. Our work highlights the utility of leveraging information from regulatory variants mapped in the liver to uncover novel variants associated with drug response and the importance of population-specific research. © 2017 International Society on Thrombosis and Haemostasis.

Recombinant Parainfluenza Virus 5 Expressing Hemagglutinin of Influenza A Virus H5N1 Protected Mice against Lethal Highly Pathogenic Avian Influenza Virus H5N1 Challenge

PubMed Central

Li, Zhuo; Mooney, Alaina J.; Gabbard, Jon D.; Gao, Xiudan; Xu, Pei; Place, Ryan J.; Hogan, Robert J.; Tompkins, S. Mark

2013-01-01

A safe and effective vaccine is the best way to prevent large-scale highly pathogenic avian influenza virus (HPAI) H5N1 outbreaks in the human population. The current FDA-approved H5N1 vaccine has serious limitations. A more efficacious H5N1 vaccine is urgently needed. Parainfluenza virus 5 (PIV5), a paramyxovirus, is not known to cause any illness in humans. PIV5 is an attractive vaccine vector. In our studies, a single dose of a live recombinant PIV5 expressing a hemagglutinin (HA) gene of H5N1 (rPIV5-H5) from the H5N1 subtype provided sterilizing immunity against lethal doses of HPAI H5N1 infection in mice. Furthermore, we have examined the effect of insertion of H5N1 HA at different locations within the PIV5 genome on the efficacy of a PIV5-based vaccine. Interestingly, insertion of H5N1 HA between the leader sequence, the de facto promoter of PIV5, and the first viral gene, nucleoprotein (NP), did not lead to a viable virus. Insertion of H5N1 HA between NP and the next gene, V/phosphorprotein (V/P), led to a virus that was defective in growth. We have found that insertion of H5N1 HA at the junction between the small hydrophobic (SH) gene and the hemagglutinin-neuraminidase (HN) gene gave the best immunity against HPAI H5N1 challenge: a dose as low as 1,000 PFU was sufficient to protect against lethal HPAI H5N1 challenge in mice. The work suggests that recombinant PIV5 expressing H5N1 HA has great potential as an HPAI H5N1 vaccine. PMID:23077314

Comparative toxicogenomic analysis of oral Cr(VI) exposure effects in rat and mouse small intestinal epithelia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kopec, Anna K.; Thompson, Chad M.; Kim, Suntae

2012-07-15

Continuous exposure to high concentrations of hexavalent chromium [Cr(VI)] in drinking water results in intestinal tumors in mice but not rats. Concentration-dependent gene expression effects were evaluated in female F344 rat duodenal and jejunal epithelia following 7 and 90 days of exposure to 0.3–520 mg/L (as sodium dichromate dihydrate, SDD) in drinking water. Whole-genome microarrays identified 3269 and 1815 duodenal, and 4557 and 1534 jejunal differentially expressed genes at 8 and 91 days, respectively, with significant overlaps between the intestinal segments. Functional annotation identified gene expression changes associated with oxidative stress, cell cycle, cell death, and immune response that weremore » consistent with reported changes in redox status and histopathology. Comparative analysis with B6C3F1 mouse data from a similarly designed study identified 2790 differentially expressed rat orthologs in the duodenum compared to 5013 mouse orthologs at day 8, and only 1504 rat and 3484 mouse orthologs at day 91. Automated dose–response modeling resulted in similar median EC{sub 50}s in the rodent duodenal and jejunal mucosae. Comparative examination of differentially expressed genes also identified divergently regulated orthologs. Comparable numbers of differentially expressed genes were observed at equivalent Cr concentrations (μg Cr/g duodenum). However, mice accumulated higher Cr levels than rats at ≥ 170 mg/L SDD, resulting in a ∼ 2-fold increase in the number of differentially expressed genes. These qualitative and quantitative differences in differential gene expression, which correlate with differences in tissue dose, likely contribute to the disparate intestinal tumor outcomes. -- Highlights: ► Cr(VI) elicits dose-dependent changes in gene expression in rat intestine. ► Cr(VI) elicits less differential gene expression in rats compared to mice. ► Cr(VI) gene expression can be phenotypically anchored to intestinal changes. ► Species-specific and divergent changes are consistent with species-specific tumors.« less

Stochastic model of transcription factor-regulated gene expression

NASA Astrophysics Data System (ADS)

Karmakar, Rajesh; Bose, Indrani

2006-09-01

We consider a stochastic model of transcription factor (TF)-regulated gene expression. The model describes two genes, gene A and gene B, which synthesize the TFs and the target gene proteins, respectively. We show through analytic calculations that the TF fluctuations have a significant effect on the distribution of the target gene protein levels when the mean TF level falls in the highest sensitive region of the dose-response curve. We further study the effect of reducing the copy number of gene A from two to one. The enhanced TF fluctuations yield results different from those in the deterministic case. The probability that the target gene protein level exceeds a threshold value is calculated with the knowledge of the probability density functions associated with the TF and target gene protein levels. Numerical simulation results for a more detailed stochastic model are shown to be in agreement with those obtained through analytic calculations. The relevance of these results in the context of the genetic disorder haploinsufficiency is pointed out. Some experimental observations on the haploinsufficiency of the tumour suppressor gene, Nkx 3.1, are explained with the help of the stochastic model of TF-regulated gene expression.

Quantitative differences in the immunomodulatory effects of Rebif and Avonex in IFN-β 1a treated multiple sclerosis patients

PubMed Central

Christophi, George P.; Christophi, Jennifer A.; Gruber, Ross C.; Mihai, Cornelia; Mejico, Luis J.; Massa, Paul T.; Jubelt, Burk

2012-01-01

Interferon-β (IFN-β) is a current effective treatment for multiple sclerosis (MS) and exerts its therapeutic effects by down-modulating the systemic immune response and cytokine signaling. In clinical practice there are several formulations of interferon including a low dose of IFN-β 1a formulation of 30μg IM once weekly (Avonex) and a high dose formulation of 44 μg SC three times weekly (Rebif). Recent studies suggest that Rebif is more efficacious compared to Avonex in preventing relapses and decreasing MRI activity in relapsing remitting MS (RRMS) patients. This study examines whether there are quantitative gene expression changes in interferon-treated RRMS patients that can explain the difference in efficacy and side effects between Rebif and Avonex. Herein, RRMS patients were treated for three months with IFN-β 1a and the levels of plasma cytokines and gene expression in peripheral blood mononuclear cells were examined. Thirty-two normal subjects were compared to thirty-two RRMS patients, of which ten were treated with Rebif and ten with Avonex. Rebif and Avonex both significantly and equally suppressed plasma TNF-α and IL-6 levels. Rebif suppressed IL-13 significantly more than Avonex. Rebif also significantly suppressed the levels of the chemokines CCL17 and RANTES, the protease ADAM8, and COX-2 at a higher degree compared to Avonex. The STAT1-inducible genes IP-10 and caspase 1 were significantly increased with Rebif compared to Avonex. In conclusion, the higher dosed, more frequently administered IFN-β 1a Rebif when compared to IFN β-1a Avonex has more potent immunomodulatory effects. These quantitative results might relate to efficacy and side-effect profile of the two IFN-β 1a formulations and provide prospective practical clinical tools to monitor treatment and adjust dosage. PMID:21658727

Gene Therapy Delivery Systems for Enhancing Viral and Nonviral Vectors for Cardiac Diseases: Current Concepts and Future Applications

PubMed Central

Katz, Michael G.; Fargnoli, Anthony S.; Williams, Richard D.

2013-01-01

Abstract Gene therapy is one of the most promising fields for developing new treatments for the advanced stages of ischemic and monogenetic, particularly autosomal or X-linked recessive, cardiomyopathies. The remarkable ongoing efforts in advancing various targets have largely been inspired by the results that have been achieved in several notable gene therapy trials, such as the hemophilia B and Leber's congenital amaurosis. Rate-limiting problems preventing successful clinical application in the cardiac disease area, however, are primarily attributable to inefficient gene transfer, host responses, and the lack of sustainable therapeutic transgene expression. It is arguable that these problems are directly correlated with the choice of vector, dose level, and associated cardiac delivery approach as a whole treatment system. Essentially, a delicate balance exists in maximizing gene transfer required for efficacy while remaining within safety limits. Therefore, the development of safe, effective, and clinically applicable gene delivery techniques for selected nonviral and viral vectors will certainly be invaluable in obtaining future regulatory approvals. The choice of gene transfer vector, dose level, and the delivery system are likely to be critical determinants of therapeutic efficacy. It is here that the interactions between vector uptake and trafficking, delivery route means, and the host's physical limits must be considered synergistically for a successful treatment course. PMID:24164239

Polymorphisms of vitamin K-related genes (EPHX1 and VKORC1L1) and stable warfarin doses.

PubMed

Chung, Jee-Eun; Lee, Kyung Eun; Chang, Byung Chul; Gwak, Hye Sun

2018-01-30

The aim of this study was to investigate the possible effects of EPHX1 and VKORC1L1 polymorphisms on variability of responses to warfarin. Sixteen single nucleotide polymorphisms (SNPs) in 201 patients with stable warfarin doses were analyzed including genes of VKORC1, CYP2C9, CYP4F2, GGCX, EPHX1 and VKORC1L1. Univariate analysis was conducted for the association of genotypes with stable warfarin doses. Multiple linear regression analysis was used to investigate factors that independently affected the inter-individual variability of warfarin dose requirements. The rs4072879 of VKORC1L1 (A>G) was significantly associated with stable warfarin doses; wild homozygote carriers (AA) required significantly lower stable warfarin doses than those with the variant G allele (5.02±1.56 vs. 5.96±2.01mg; p=0.001). Multivariate analysis showed that EPHX1 rs1877724 and VKORC1L1 rs4072879 accounted for 1.5% and 1.3% of the warfarin dose variability. Adding EPHX1 and VKORC1L1 SNPs to the base model including non-genetic variables (operation age, body weight and the therapy of ACEI or ARB) and genetic variables (VKORC1 rs9934438, CYP2C9 rs1057910, and CYP4F2 rs2108622) gave a number needed to genotype of 34. This study showed that polymorphisms of EPHX1 and VKORC1L1 could be determinants of stable warfarin doses. Copyright © 2017. Published by Elsevier B.V.

Histone Deacetylase Inhibitors Enhance Cytotoxicity Towards Breast Tumors While Preserving the Wound-Healing Function of Adipose-Derived Stem Cells.

PubMed

Koko, Kiavash R; Chang, Shaohua; Hagaman, Ashleigh L; Fromer, Marc W; Nolan, Ryan S; Gaughan, John P; Zhang, Ping; Carpenter, Jeffrey P; Brown, Spencer A; Matthews, Martha; Bird, Dorothy

2017-06-01

Paclitaxel improves the oncologic response of breast cancer resections; however, it may negatively affect the wound-healing potential of human adipose-derived stem cells (hASCs) for fat grafting and reconstructive surgery. Histone deacetylase inhibitors (HDACis) modify the epigenetic regulation of gene expression and stabilize microtubules similarly to paclitaxel, thus, creating a synergistic mechanism of cell cycle arrest. We aim to combine these drugs to enhance cytotoxicity towards breast cancer cells, while preserving the wound-healing function of hASCs for downstream reconstructive applications. Triple negative breast cancer cells (MBA-MB-231) and hASCs (institutional review board-approved clinical isolates) were treated with a standard therapeutic dose of paclitaxel (1.0 μM) or with low-dose paclitaxel (0.1 μM) combined with the HDACi suberoylanilide hydroxamic acid or trichostatin A. Cell viability, gene expression, apoptosis, and wound-healing/migration were measured via methylthiazol tetrazolium assay, quantitative real-time polymerase chain reaction, annexin V assay, and fibroblast scratch assay, respectively. Combined HDACi and low-dose paclitaxel therapy maintained cytotoxicity towards breast cancer cells and preserved adipose-derived stem cell viability. Histone deacetylase inhibitor demonstrated selective anti-inflammatory effects on adipose-derived stem cell gene expression and decreased expression of the proapoptotic gene FAS. Furthermore, HDACi therapy did not increase relative apoptosis within hASCs. A scratch assay demonstrated enhanced wound healing among injured fibroblasts indirectly co-cultured with HDACi-treated hASCs. Combining HDACi with low-dose paclitaxel improved cytotoxicity towards breast cancer cells and preserved hASC viability. Furthermore, enhanced wound healing was observed by improved migration in a fibroblast scratch assay. These results suggest that the addition of HDACi to taxane chemotherapy regimens may improve oncologic results and wound-healing outcomes after reconstructive surgery.

Expression patterns and promoter analyses of aluminum-responsive NAC genes suggest a possible growth regulation of rice mediated by aluminum, hormones and NAC transcription factors.

PubMed

Escobar-Sepúlveda, Hugo Fernando; Trejo-Téllez, Libia Iris; García-Morales, Soledad; Gómez-Merino, Fernando Carlos

2017-01-01

In acid soils, the solubilized form of aluminum, Al+3, decreases root growth and affects the development of most crops. However, like other toxic elements, Al can have hormetic effects on plant metabolism. Rice (Oryza sativa) is one of the most tolerant species to Al toxicity, and when this element is supplied at low doses, growth stimulation has been observed, which could be due to combined mechanisms that are partly triggered by NAC transcription factors. This protein family can regulate vital processes in plants, including growth, development, and response to environmental stimuli, whether biotic or abiotic. Under our experimental conditions, 200 μM Al stimulated root growth and the formation of tillers; it also caused differential expression of a set of NAC genes. The promoter regions of the genes regulated by Al were analyzed and the cis-acting elements that are potentially involved in the responses to different stimuli, including environmental stress, were identified. Through the Genevestigator platform, data on the expression of NAC genes were obtained by experimental condition, tissue, and vegetative stage. This is the first study on NAC genes where in vivo and in silico data are complementarily analyzed, relating the hormetic effect of Al on plant growth and gene expression with a possible interaction in the response to phytohormones in rice. These findings could help to elucidate the possible convergence between the signaling pathways mediated by phytohormones and the role of the NAC transcription factors in the regulation of growth mediated by low Al doses.

Expression patterns and promoter analyses of aluminum-responsive NAC genes suggest a possible growth regulation of rice mediated by aluminum, hormones and NAC transcription factors

PubMed Central

2017-01-01

In acid soils, the solubilized form of aluminum, Al+3, decreases root growth and affects the development of most crops. However, like other toxic elements, Al can have hormetic effects on plant metabolism. Rice (Oryza sativa) is one of the most tolerant species to Al toxicity, and when this element is supplied at low doses, growth stimulation has been observed, which could be due to combined mechanisms that are partly triggered by NAC transcription factors. This protein family can regulate vital processes in plants, including growth, development, and response to environmental stimuli, whether biotic or abiotic. Under our experimental conditions, 200 μM Al stimulated root growth and the formation of tillers; it also caused differential expression of a set of NAC genes. The promoter regions of the genes regulated by Al were analyzed and the cis-acting elements that are potentially involved in the responses to different stimuli, including environmental stress, were identified. Through the Genevestigator platform, data on the expression of NAC genes were obtained by experimental condition, tissue, and vegetative stage. This is the first study on NAC genes where in vivo and in silico data are complementarily analyzed, relating the hormetic effect of Al on plant growth and gene expression with a possible interaction in the response to phytohormones in rice. These findings could help to elucidate the possible convergence between the signaling pathways mediated by phytohormones and the role of the NAC transcription factors in the regulation of growth mediated by low Al doses. PMID:29023561

Prostanoid-induced expression of matrix metalloproteinase-1 messenger ribonucleic acid in rat osteosarcoma cells

NASA Technical Reports Server (NTRS)

Clohisy, J. C.; Connolly, T. J.; Bergman, K. D.; Quinn, C. O.; Partridge, N. C.

1994-01-01

Individual prostanoids have distinct potencies in activating intracellular signaling pathways and regulating gene expression in osteoblastic cells. The E-series prostaglandins (PGs) are known to stimulate matrix metalloproteinase-1 (MMP-1) synthesis and secretion in certain rodent and human osteoblastic cells, yet the intracellular events involved remain unclear. To further characterize this response and its signal transduction pathway(s), we examined prostanoid-induced expression of the MMP-1 gene in the rat osteoblastic osteosarcoma cell line UMR 106-01. Northern blot analysis demonstrated that prostaglandin E2 (PGE2) and PGE1 were very potent stimulators (40-fold) of MMP-1 transcript abundance, PGF2 alpha and prostacyclin were weak stimulators (4-fold), and thromboxane-B2 had no effect. The marked increase in MMP-1 transcript abundance after PGE2 treatment was first detected at 2 h, became maximal at 4 h, and persisted beyond 24 h. This response was dose dependent and elicited maximal and half-maximal effects with concentrations of 10(-6) and 0.6 x 10(-7) M, respectively. Cycloheximide, a protein synthesis inhibitor, completely blocked this effect of PGE2, suggesting that the expression of other genes is required. Nuclear run-on experiments demonstrated that PGE2 rapidly activates MMP-1 gene transcription, with a maximal increase at 2-4 h. The second messenger analog, 8-bromo-cAMP, mimicked the effects of PGE2 by stimulating a dose-dependent increase in MMP-1 messenger RNA (mRNA) levels, with a maximal effect quantitatively similar to that observed with PGE2. Thus, in UMR 106-01 cells, different prostanoids have distinct potencies in stimulating MMP-1 mRNA abundance. Our data suggest that PGE2 stimulation of MMP-1 synthesis is due to activation of MMP-1 gene transcription and a subsequent marked increase in MMP-1 mRNA abundance. This effect is dependent on de novo protein synthesis and is mimicked by protein kinase-A activation.

Doxorubicin In Vivo Rapidly Alters Expression and Translation of Myocardial Electron Transport Chain Genes, Leads to ATP Loss and Caspase 3 Activation

PubMed Central

Pointon, Amy V.; Walker, Tracy M.; Phillips, Kate M.; Luo, Jinli; Riley, Joan; Zhang, Shu-Dong; Parry, Joel D.; Lyon, Jonathan J.; Marczylo, Emma L.; Gant, Timothy W.

2010-01-01

Background Doxorubicin is one of the most effective anti-cancer drugs but its use is limited by cumulative cardiotoxicity that restricts lifetime dose. Redox damage is one of the most accepted mechanisms of toxicity, but not fully substantiated. Moreover doxorubicin is not an efficient redox cycling compound due to its low redox potential. Here we used genomic and chemical systems approaches in vivo to investigate the mechanisms of doxorubicin cardiotoxicity, and specifically test the hypothesis of redox cycling mediated cardiotoxicity. Methodology/Principal Findings Mice were treated with an acute dose of either doxorubicin (DOX) (15 mg/kg) or 2,3-dimethoxy-1,4-naphthoquinone (DMNQ) (25 mg/kg). DMNQ is a more efficient redox cycling agent than DOX but unlike DOX has limited ability to inhibit gene transcription and DNA replication. This allowed specific testing of the redox hypothesis for cardiotoxicity. An acute dose was used to avoid pathophysiological effects in the genomic analysis. However similar data were obtained with a chronic model, but are not specifically presented. All data are deposited in the Gene Expression Omnibus (GEO). Pathway and biochemical analysis of cardiac global gene transcription and mRNA translation data derived at time points from 5 min after an acute exposure in vivo showed a pronounced effect on electron transport chain activity. This led to loss of ATP, increased AMPK expression, mitochondrial genome amplification and activation of caspase 3. No data gathered with either compound indicated general redox damage, though site specific redox damage in mitochondria cannot be entirely discounted. Conclusions/Significance These data indicate the major mechanism of doxorubicin cardiotoxicity is via damage or inhibition of the electron transport chain and not general redox stress. There is a rapid response at transcriptional and translational level of many of the genes coding for proteins of the electron transport chain complexes. Still though ATP loss occurs with activation caspase 3 and these events probably account for the heart damage. PMID:20856801

Familial Hypercholesterolaemia

PubMed Central

Marais, A David

2004-01-01

Familial hypercholesterolaemia (FH), defined as the heritable occurrence of severe hypercholesterolaemia with cholesterol deposits in tendons and premature heart disease, is caused by at least four genes in sterol and lipoprotein pathways and displays varying gene-dose effects. The genes are the low-density lipoprotein (LDL) receptor, apolipoprotein (apo) B, proprotein convertase subtilisin/kexin 9, and the autosomal recessive hypercholesterolaemia (ARH) adaptor protein. All of these disorders have in common defective clearance of LDL within a complex system of lipid and lipoprotein metabolism and regulation. Normal cellular cholesterol and lipoprotein metabolism is reviewed before describing the disorders, their metabolic derangements and their clinical effects. FH is classified as two simplified phenotypes of disease according to the severity of the metabolic derangement. The dominantly inherited heterozygous phenotype comprises defects in the LDL receptor, apoB100, and neural apoptosis regulatory cleavage protein. The homozygous phenotype is co-dominant in defects of the LDL receptor, and occurs also as the ARH of adapter protein mutations. Defective binding of apoB100 does not result in a significant gene dose effect, but enhances the severity of heterozygotes for LDL receptor mutations. The genetic diagnosis of FH has provided greater accuracy in definition and detection of disease and exposes information about migration of populations. All of these disorders pose a high risk of atherosclerosis, especially in the homozygous phenotype. Studies of influences on the phenotype and responses to treatment are also discussed in the context of the metabolic derangements. PMID:18516203

Bisphenol A-Associated Alterations in the Expression and Epigenetic Regulation of Genes Encoding Xenobiotic Metabolizing Enzymes in Human Fetal Liver

PubMed Central

Nahar, Muna S.; Kim, Jung H.; Sartor, Maureen A.; Dolinoy, Dana C.

2014-01-01

Alterations in xenobiotic metabolizing enzyme (XME) expression across the life course, along with genetic, nutritional, and environmental regulation, can influence how organisms respond to toxic insults. In this study, we investigated the hypothesis that in utero exposure to the endocrine active compound, bisphenol A (BPA), influences expression and epigenetic regulation of phase I and II XME genes during development. Using healthy 1st to 2nd trimester human fetal liver specimens quantified for internal BPA levels, we examined XME gene expression using PCR Array (n =8) and RNA-sequencing (n =12) platforms. Of the greater than 160 XME genes assayed, 2 phase I and 12 phase II genes exhibited significantly reduced expression with higher BPA levels, including isoforms from the carboxylesterase, catechol O-methyltransferase, glutathione S-transferase, sulfotransferase, and UDP-glucuronosyltransferase families. When the promoters of these candidate genes were evaluated in silico, putative binding sites for the E-twenty-six (ETS) and activator protein1 (AP1) related transcription factor families were identified and unique to 97% of all candidate transcripts. Interestingly, many ETS binding sites contain cytosine-guanine dinucleotides (CpGs) within their consensus sequences. Thus, quantitative analysis of CpG methylation of three candidate genes was conducted across n =50 samples. Higher BPA levels were associated with increased site-specific methylation at COMT (P <0.005) and increased average methylation at SULT2A1 (P <0.020) promoters. While toxicological studies have traditionally focused on high-dose effects and hormonal receptor mediated regulation, our findings suggest the importance of low-dose effects and nonclassical mechanisms of endocrine disruption during development. PMID:24214726

Transcriptome profile analysis reflects rat liver and kidney damage following chronic ultra-low dose Roundup exposure.

PubMed

Mesnage, Robin; Arno, Matthew; Costanzo, Manuela; Malatesta, Manuela; Séralini, Gilles-Eric; Antoniou, Michael N

2015-08-25

Glyphosate-based herbicides (GBH) are the major pesticides used worldwide. Converging evidence suggests that GBH, such as Roundup, pose a particular health risk to liver and kidneys although low environmentally relevant doses have not been examined. To address this issue, a 2-year study in rats administering 0.1 ppb Roundup (50 ng/L glyphosate equivalent) via drinking water (giving a daily intake of 4 ng/kg bw/day of glyphosate) was conducted. A marked increased incidence of anatomorphological and blood/urine biochemical changes was indicative of liver and kidney structure and functional pathology. In order to confirm these findings we have conducted a transcriptome microarray analysis of the liver and kidneys from these same animals. The expression of 4224 and 4447 transcript clusters (a group of probes corresponding to a known or putative gene) were found to be altered respectively in liver and kidney (p < 0.01, q < 0.08). Changes in gene expression varied from -3.5 to 3.7 fold in liver and from -4.3 to 5.3 in kidneys. Among the 1319 transcript clusters whose expression was altered in both tissues, ontological enrichment in 3 functional categories among 868 genes were found. First, genes involved in mRNA splicing and small nucleolar RNA were mostly upregulated, suggesting disruption of normal spliceosome activity. Electron microscopic analysis of hepatocytes confirmed nucleolar structural disruption. Second, genes controlling chromatin structure (especially histone-lysine N-methyltransferases) were mostly upregulated. Third, genes related to respiratory chain complex I and the tricarboxylic acid cycle were mostly downregulated. Pathway analysis suggests a modulation of the mTOR and phosphatidylinositol signalling pathways. Gene disturbances associated with the chronic administration of ultra-low dose Roundup reflect a liver and kidney lipotoxic condition and increased cellular growth that may be linked with regeneration in response to toxic effects causing damage to tissues. Observed alterations in gene expression were consistent with fibrosis, necrosis, phospholipidosis, mitochondrial membrane dysfunction and ischemia, which correlate with and thus confirm observations of pathology made at an anatomical, histological and biochemical level. Our results suggest that chronic exposure to a GBH in an established laboratory animal toxicity model system at an ultra-low, environmental dose can result in liver and kidney damage with potential significant health implications for animal and human populations.

JIL-1 and Su(var)3-7 Interact Genetically and Counteract Each Other's Effect on Position-Effect Variegation in Drosophila

PubMed Central

Deng, Huai; Cai, Weili; Wang, Chao; Lerach, Stephanie; Delattre, Marion; Girton, Jack; Johansen, Jørgen; Johansen, Kristen M.

2010-01-01

The essential JIL-1 histone H3S10 kinase is a key regulator of chromatin structure that functions to maintain euchromatic domains while counteracting heterochromatization and gene silencing. In the absence of the JIL-1 kinase, two of the major heterochromatin markers H3K9me2 and HP1a spread in tandem to ectopic locations on the chromosome arms. Here we address the role of the third major heterochromatin component, the zinc-finger protein Su(var)3-7. We show that the lethality but not the chromosome morphology defects associated with the null JIL-1 phenotype to a large degree can be rescued by reducing the dose of the Su(var)3-7 gene and that Su(var)3-7 and JIL-1 loss-of-function mutations have an antagonistic and counterbalancing effect on position-effect variegation (PEV). Furthermore, we show that in the absence of JIL-1 kinase activity, Su(var)3-7 gets redistributed and upregulated on the chromosome arms. Reducing the dose of the Su(var)3-7 gene dramatically decreases this redistribution; however, the spreading of H3K9me2 to the chromosome arms was unaffected, strongly indicating that ectopic Su(var)3-9 activity is not a direct cause of lethality. These observations suggest a model where Su(var)3-7 functions as an effector downstream of Su(var)3-9 and H3K9 dimethylation in heterochromatic spreading and gene silencing that is normally counteracted by JIL-1 kinase activity. PMID:20457875

NASA GeneLab Project: Bridging Space Radiation Omics with Ground Studies

NASA Technical Reports Server (NTRS)

Beheshti, Afshin; Miller, Jack; Kidane, Yared H.; Berrios, Daniel; Gebre, Samrawit G.; Costes, Sylvain V.

2018-01-01

Accurate assessment of risk factors for long-term space missions is critical for human space exploration: therefore it is essential to have a detailed understanding of the biological effects on humans living and working in deep space. Ionizing radiation from Galactic Cosmic Rays (GCR) is one of the major risk factors factor that will impact health of astronauts on extended missions outside the protective effects of the Earth's magnetic field. Currently there are gaps in our knowledge of the health risks associated with chronic low dose, low dose rate ionizing radiation, specifically ions associated with high (H) atomic number (Z) and energy (E). The GeneLab project (genelab.nasa.gov) aims to provide a detailed library of Omics datasets associated with biological samples exposed to HZE. The GeneLab Data System (GLDS) currently includes datasets from both spaceflight and ground-based studies, a majority of which involve exposure to ionizing radiation. In addition to detailed information for ground-based studies, we are in the process of adding detailed, curated dosimetry information for spaceflight missions. GeneLab is the first comprehensive Omics database for space related research from which an investigator can generate hypotheses to direct future experiments utilizing both ground and space biological radiation data. In addition to previously acquired data, the GLDS is continually expanding as Omics related data are generated by the space life sciences community. Here we provide a brief summary of space radiation related data available at GeneLab.

A Controlled Pharmacogenetic Trial of Sibutramine on Weight Loss and Body Composition in Obese or Overweight Adults

PubMed Central

Grudell, April B.M.; Sweetser, Seth; Camilleri, Michael; Eckert, Deborah J.; Vazquez-Roque, Maria I.; Carlson, Paula J.; Burton, Duane D.; Braddock, Autumn E.; Clark, Matthew M.; Graszer, Karen M.; Kalsy, Sarah A.; Zinsmeister, Alan R.

2008-01-01

Background/ Aim Weight loss in response to sibutramine is highly variable. We assessed the association of specific markers of polymorphisms of candidate a2A adrenoreceptor, 5-HT transporter and GNβ3 genes and weight loss with sibutramine. Methods We conducted a randomized, double-blind, pharmacogenetic study of behavioral therapy and sibutramine (10 or 15 mg daily) or placebo for 12 weeks in 181 overweight or obese participants. We measured body weight, BMI, body composition, gastric emptying and genetic variation (α2A C1291G, 5-HTTLPR, and GNβ3 C825T genotypes). ANCOVA was used to assess treatment effects on, and associations of the specific markers of candidate genes with weight loss and body composition. Results Sibutramine, 10 and 15 mg, caused significant weight loss (p = 0.009); there was a statistically significant gene by dose interaction for GNβ3 genotype. For each candidate gene, significant treatment effects at 12 weeks were observed (p<0.017) for all specific genotype variants (delta weight loss in the 2 sibutramine doses versus placebo): α2A CC genotype ( Δ ~5kg), GNβ3 TC/TT genotype (Δ ~6kg), and 5-HTTLPR LS/SS (Δ ~4.5kg). Gene pairs resulted in significantly greater sibutramine treatment effects on weight (both p<0.002): in participants with 5-HTTLPR LS/SS with GNβ3 TC/TT, Δ ~6kg and those with a2A CC with GNβ3 TC/TT, Δ ~8kg; however, effects were not synergistic. Treatment with sibutramine also resulted in significantly greater reduction of body fat for specific α2A CC and GNβ3 TC/TT genotype variants individually (both p<0.02). Conclusions Selection of patients with obesity based on candidate genes may enhance response to multidimensional sibutramine and behavioral therapy. PMID:18725220

Sperm viability and gene expression in honey bee queens (Apis mellifera) following exposure to the neonicotinoid insecticide imidacloprid and the organophosphate acaricide coumaphos.

PubMed

Chaimanee, Veeranan; Evans, Jay D; Chen, Yanping; Jackson, Caitlin; Pettis, Jeffery S

2016-06-01

Honey bee population declines are of global concern. Numerous factors appear to cause these declines including parasites, pathogens, malnutrition and pesticides. Residues of the organophosphate acaricide coumaphos and the neonicotinoid insecticide imidacloprid, widely used to combat Varroa mites and for crop protection in agriculture, respectively, have been detected in wax, pollen and comb samples. Here, we assess the effects of these compounds at different doses on the viability of sperm stored in the honey bee queens' spermatheca. Our results demonstrate that sub-lethal doses of imidacloprid (0.02ppm) decreased sperm viability by 50%, 7days after treatment. Sperm viability was a downward trend (about 33%) in queens treated with high doses of coumaphos (100ppm), but there was not significant difference. The expression of genes that are involved in development, immune responses and detoxification in honey bee queens and workers exposed to chemicals was measured by qPCR analysis. The data showed that expression levels of specific genes were triggered 1day after treatment. The expression levels of P450 subfamily genes, CYP306A1, CYP4G11 and CYP6AS14 were decreased in honey bee queens treated with low doses of coumaphos (5ppm) and imidacloprid (0.02ppm). Moreover, these two compounds suppressed the expression of genes related to antioxidation, immunity and development in queens at day 1. Up-regulation of antioxidants by these compounds in worker bees was observed at day 1. Coumaphos also caused a repression of CYP306A1 and CYP4G11 in workers. Antioxidants appear to prevent chemical damage to honey bees. We also found that DWV replication increased in workers treated with imidacloprid. This research clearly demonstrates that chemical exposure can affect sperm viability in queen honey bees. Copyright © 2016 Elsevier Ltd. All rights reserved.

Exposure of luminous marine bacteria to low-dose gamma-radiation.

PubMed

Kudryasheva, N S; Petrova, A S; Dementyev, D V; Bondar, A A

2017-04-01

The study addresses biological effects of low-dose gamma-radiation. Radioactive 137 Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested. To investigate the sensitivity of the bacteria to the low-dose gamma-radiation exposure (≤250 mGy), the irradiation conditions were varied as follows: bioluminescence intensity was measured at 5, 10, and 20°С for 175, 100, and 47 h, respectively, at different dose rates (up to 4100 μGy/h). There was no noticeable effect of gamma-radiation at 5 and 10°С, while the 20°С exposure revealed authentic bioluminescence inhibition. The 20°С results of gamma-radiation exposure were compared to those for low-dose alpha- and beta-radiation exposures studied previously under comparable experimental conditions. In contrast to ionizing radiation of alpha and beta types, gamma-emission did not initiate bacterial bioluminescence activation (adaptive response). As with alpha- and beta-radiation, gamma-emission did not demonstrate monotonic dose-effect dependencies; the bioluminescence inhibition efficiency was found to be related to the exposure time, while no dose rate dependence was found. The sequence analysis of 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose gamma radiation. The exposure time that caused 50% bioluminescence inhibition was suggested as a test parameter for radiotoxicity evaluation under conditions of chronic low-dose gamma irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Text mining-based in silico drug discovery in oral mucositis caused by high-dose cancer therapy.

PubMed

Kirk, Jon; Shah, Nirav; Noll, Braxton; Stevens, Craig B; Lawler, Marshall; Mougeot, Farah B; Mougeot, Jean-Luc C

2018-08-01

Oral mucositis (OM) is a major dose-limiting side effect of chemotherapy and radiation used in cancer treatment. Due to the complex nature of OM, currently available drug-based treatments are of limited efficacy. Our objectives were (i) to determine genes and molecular pathways associated with OM and wound healing using computational tools and publicly available data and (ii) to identify drugs formulated for topical use targeting the relevant OM molecular pathways. OM and wound healing-associated genes were determined by text mining, and the intersection of the two gene sets was selected for gene ontology analysis using the GeneCodis program. Protein interaction network analysis was performed using STRING-db. Enriched gene sets belonging to the identified pathways were queried against the Drug-Gene Interaction database to find drug candidates for topical use in OM. Our analysis identified 447 genes common to both the "OM" and "wound healing" text mining concepts. Gene enrichment analysis yielded 20 genes representing six pathways and targetable by a total of 32 drugs which could possibly be formulated for topical application. A manual search on ClinicalTrials.gov confirmed no relevant pathway/drug candidate had been overlooked. Twenty-five of the 32 drugs can directly affect the PTGS2 (COX-2) pathway, the pathway that has been targeted in previous clinical trials with limited success. Drug discovery using in silico text mining and pathway analysis tools can facilitate the identification of existing drugs that have the potential of topical administration to improve OM treatment.

Memory-enhancing effect of aspirin is mediated through opioid system modulation in an AlCl3-induced neurotoxicity mouse model

PubMed Central

RIZWAN, SAIMA; IDREES, AYESHA; ASHRAF, MUHAMMAD; AHMED, TOUQEER

2016-01-01

Neurodegenerative disorders such as Alzheimers disease (AD) are multifaceted and there are currently a limited number of therapeutic strategies available to treat them. Aspirin is known to act on multiple therapeutic targets and is a successful anti-inflammatory agent in various tissues. The present study aimed to ascertain the performance of aspirin when employed as a therapeutic agent to treat neurodegeneration on novel targets, including opioid system genes, in an AlCl3-induced neurotoxicity mouse model. The effects of two doses of aspirin (5 and 20 mg/kg aspirin for 12 days) were investigated in an AlCl3-induced neurotoxicity mouse model (150 mg/kg AlCl3 for 12 days). Neurological improvements were assessed through different behavioral tests and the effects of aspirin on opioid system gene expression levels were assessed by reverse transcription-polymerase chain reaction. Both doses resulted in improvements in cognitive behavior. A 5 mg/kg dose of aspirin was revealed to be effective for spatial memory improvement (7.14±0.84 sec), whilst a 20 mg/kg dose was superior for improving extinction learning (7.63±4.04%). Aspirin (5 mg/kg) also significantly improved contextual memory (48.05±10.6%) when compared with the AlCl3-treated group (1.49±0.62%; P<0.001). Aspirin was also observed to significantly decrease δ-opioid receptor expression in the cortex (1.09±0.08 and 1.27±0.08, respectively) at both doses (5 and 20 mg/kg) when compared with the AlCl3-treated group (3.69±1.43; P<0.05). Furthermore, aspirin at 5 mg/kg significantly reduced expression of prodynorphin in the cortex (0.57±0.20) when compared with the AlCl3-treated group (1.95±0.84; P<0.05). Notably, the effect of aspirin was significant in the cortex but not in the hippocampus. In summary, aspirin was effective in ameliorating the AD-like symptoms via the modulation of opioid systems. However, additional studies are required to determine the long term effects of aspirin on such conditions. PMID:27168835

Low dose evaluation of the antiandrogen flutamide following a Mode of Action approach.

PubMed

Sarrabay, A; Hilmi, C; Tinwell, H; Schorsch, F; Pallardy, M; Bars, R; Rouquié, D

2015-12-15

The dose-response characterization of endocrine mediated toxicity is an on-going debate which is controversial when exploring the nature of the dose-response curve and the effect at the low-end of the curve. To contribute to this debate we have assessed the effects of a wide range of dose levels of the antiandrogen flutamide (FLU) on 7-week male Wistar rats. FLU was administered by oral gavage at doses of 0, 0.001, 0.01, 0.1, 1 and 10mg/kg/day for 28 days. To evaluate the reproducibility, the study was performed 3 times. The molecular initiating event (MIE; AR antagonism), the key events (LH increase, Leydig cell proliferation and hyperplasia increases) and associated events involved in the mode of action (MOA) of FLU induced testicular toxicity were characterized to address the dose response concordance. Results showed no effects at low doses (<0.1mg/kg/day) for the different key events studied. The histopathological changes (Leydig cell hyperplasia) observed at 1 and 10mg/kg/day were associated with an increase in steroidogenesis gene expression in the testis from 1mg/kg/day, as well as an increase in testosterone blood level at 10mg/kg/day. Each key event dose-response was in good concordance with the MOA of FLU on the testis. From the available results, only monotonic dose-response curves were observed for the MIE, the key events, associated events and in effects observed in other sex related tissues. All the results, so far, show that the reference endocrine disruptor FLU induces threshold effects in a standard 28-day toxicity study on adult male rats. Copyright © 2015 Elsevier Inc. All rights reserved.

Toxicology and cellular effect of manufactured nanomaterials

DOEpatents

Chen, Fanqing

2014-07-22

The increasing use of nanotechnology in consumer products and medical applications underlies the importance of understanding its potential toxic effects to people and the environment. Herein are described methods and assays to predict and evaluate the cellular effects of nanomaterial exposure. Exposing cells to nanomaterials at cytotoxic doses induces cell cycle arrest and increases apoptosis/necrosis, activates genes involved in cellular transport, metabolism, cell cycle regulation, and stress response. Certain nanomaterials induce genes indicative of a strong immune and inflammatory response within skin fibroblasts. Furthermore, the described multiwall carbon nanoonions (MWCNOs) can be used as a therapeutic in the treatment of cancer due to its cytotoxicity.

Gene hypermethylation in blood leukocytes in humans long term after radiation exposure - Validation set.

PubMed

Kuzmina, Nina S; Lapteva, Nellya Sh; Rusinova, Galina G; Azizova, Tamara V; Vyazovskaya, Natalya S; Rubanovich, Alexander V

2018-03-01

Hypermethylation of СpG islands in the promoter regions of several genes with basic protective function in blood leukocytes of individuals exposed to ionizing radiation long time ago (2-46 years), and differential effects of age and radiation exposure on hypermethylation was reported in our previous work. To validate these results, epigenetic modifications were assessed in an independent series of 49 nuclear industry workers from the "Mayak" facility (67-84 years old at sampling) with documented individual accumulated doses from the prolonged external γ-radiation exposure (95.9-409.5 cGy, end of work with radiation:0.3-39 years ago), and in 50 non-exposed persons matched by age. In addition to the genes analyzed before (RASSF1A, p16/INK4A, p14/ARF, GSTP1), four additional loci were analyzed: TP53, ATM, SOD3, ESR1. The frequency of individuals displaying promoter methylation of at least one of the 8 genes (71.4%) was significantly higher in exposed group as compared to the control group (40%), p = .002, OR = 3.75. A significantly elevated frequency of individuals with hypermethylated СpG islands in GSTP1, TP53, SOD3 promoters was revealed among exposed subjects as compared to the control group (p = .012, OR = 8.41; p = .041, OR = 4.02 and p = .009, OR = 3.42, respectively). A similar trend (p = .12, OR = 3.06) was observed for the p16/INK4A gene. As a whole, p16/INK4A and GSTP1 promoter hypermethylation in irradiated subjects from both previously and currently analyzed groups was pronounced. Thus, the direction of the effects was fully confirmed, suggesting the result reproducibility. No statistically significant correlation between promoter methylation and individual radiation dose was found. Further studies are required to create an array of blood epigenetic markers of radiation exposure associating with premature aging and age-related diseases and to accurately evaluate radiation-added effect across the range of doses. The results of studies of epigenetic changes in two independent samples of irradiated subjects indicated the significance of radiation factor in the induction of hypermethylation of CpG islands in gene promoters that is revealed in blood cells years and decades after exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hepatic, metabolic and toxicity evaluation of repeated oral administration of SnS2 nanoflowers in mice.

PubMed

Bai, Disi; Li, Qingzhao; Xiong, Yanjie; Wang, Chao; Shen, Peijun; Bai, Liyuan; Yuan, Lu; Wu, Ping

2018-05-02

Tin sulphide (SnS2) nanoflowers (NFs) with highly photocatalytic activity for wastewater treatment may lead to potential health hazards via oral routes of human exposure. No studies have reported the hepatic effects of SnS2 NFs on the metabolic function and hepatotoxicity. In this study, we examined the hepatic effects of the oral administration of SnS2 NFs (250-1000 mg/kg) to ICR mice for 14 d, with the particle size ranging from 50 to 200 nm. Serum and liver tissue samples were assayed using biochemical analysis, liver histopathology and metabolic gene expression. The different sizes of SnS2 NFs (250 mg/kg dose), such as 50, 80 and 200 nm, did not induce any adverse hepatic effect related to biochemical parameters or histopathology in the treated mice compared with controls. The oral administration of 50-nm SnS2 NFs at doses of 250, 500 and 1000 mg/kg for 14 d produced dose-dependent hepatotoxicity and inflammatory responses in treated mice. Furthermore, the expression of metabolic genes in the liver tissues was altered, supporting the SnS2 NF-related hepatotoxic phenotype. The oral administration of SnS2 NFs also produced abnormal microstructures in the livers of the treated mice. Taken together, these data indicate that the increased risk of hepatotoxicity in SnS2 NF-treated mice was independent of the particle size but was dependent on their dose. The no-observed-adverse effect level was <250 mg/kg for the 50-nm SnS2 NFs. Our study provides an experimental basis for the safe application of SnS2 NFs.

GENE EXPRESSION CHANGES IN MOUSE BLADDER TISSUE IN RESPONSE TO INORGANIC ARSENIC

EPA Science Inventory

Chronic human exposures to high arsenic concentrations are associated with lung, skin, and bladder cancer. Considerable controversy exists concerning arsenic mode of action and low dose extrapolation. This investigation was designed to identify dose-response changes in gene expre...

[Effect of tagalsin on p53 and Bcl-2 expression in hepatoma H(22) tumor-bearing mice].

PubMed

Song, Xiu-qi; Guo, Yun-liang; Wang, Bing-gao; Sun, Shao-jie; Yao, Ru-yong

2011-07-01

To explore the effect and mechanism of tagalsin on hepatoma cells. The animal models were established by transplanting H(22) mouse hepatoma cells to mouse liver, and ten days later the mice were randomly divided into five groups: blank group, carmofur positive group and tagalsin groups, including low-dose, middle-dose and high-dose groups. Then medicine or oil was given to the mice by gastric gavage in consecutive 5 days with a 2-days interval as a course of treatment, two courses in all. All mice were killed at 24 hours after medication, and the survival period, ascites conditions, aggressive conditions intra- or extra-liver, weight changes, tumor volume and spleen index of the tumor-bearing mice were observed. Pathological changes of the tumors were examined. Apoptotic factors p53 and Bcl-2 protien and mRNA were detected by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). tagalsin inhibited the hepatoma growth effectively without influencing spleen index to some extent. The tumor inhibition rate of tagalsin low, middle and high dose groups were 17.9%, 63.1% and 71.8%, respectively. Immunohistochemical results showed that the p53 and Bcl-2 protein positive cell counts of the positive control and experimental groups were significantly lower than those of the blank group (P < 0.01). RT-PCR results showed that the p53 mRNA expression was significantly enhanced and Bcl-2 mRNA expression was decreased in the positive control groups and tagalsin treatment groups, especially in the high dose group, compared with those of the blank group (P < 0.05). tagalsin can inhibit the growth of mouse hepatoma cells significantly. The mechanism of its anti-tumor effect may work via up-regulating the wild type p53 gene expression and down-regulating Bcl-2 gene expression and thus regulating tumor cell apoptosis.

Methylene blue upregulates Nrf2/ARE genes and prevents tau-related neurotoxicity

PubMed Central

Stack, Cliona; Jainuddin, Shari; Elipenahli, Ceyhan; Gerges, Meri; Starkova, Natalia; Starkov, Anatoly A.; Jové, Mariona; Portero-Otin, Manuel; Launay, Nathalie; Pujol, Aurora; Kaidery, Navneet Ammal; Thomas, Bobby; Tampellini, Davide; Beal, M. Flint; Dumont, Magali

2014-01-01

Methylene blue (MB, methylthioninium chloride) is a phenothiazine that crosses the blood brain barrier and acts as a redox cycler. Among its beneficial properties are its abilities to act as an antioxidant, to reduce tau protein aggregation and to improve energy metabolism. These actions are of particular interest for the treatment of neurodegenerative diseases with tau protein aggregates known as tauopathies. The present study examined the effects of MB in the P301S mouse model of tauopathy. Both 4 mg/kg MB (low dose) and 40 mg/kg MB (high dose) were administered in the diet ad libitum from 1 to 10 months of age. We assessed behavior, tau pathology, oxidative damage, inflammation and numbers of mitochondria. MB improved the behavioral abnormalities and reduced tau pathology, inflammation and oxidative damage in the P301S mice. These beneficial effects were associated with increased expression of genes regulated by NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE), which play an important role in antioxidant defenses, preventing protein aggregation, and reducing inflammation. The activation of Nrf2/ARE genes is neuroprotective in other transgenic mouse models of neurodegenerative diseases and it appears to be an important mediator of the neuroprotective effects of MB in P301S mice. Moreover, we used Nrf2 knock out fibroblasts to show that the upregulation of Nrf2/ARE genes by MB is Nrf2 dependent and not due to secondary effects of the compound. These findings provide further evidence that MB has important neuroprotective effects that may be beneficial in the treatment of human neurodegenerative diseases with tau pathology. PMID:24556215

Methylene blue upregulates Nrf2/ARE genes and prevents tau-related neurotoxicity.

PubMed

Stack, Cliona; Jainuddin, Shari; Elipenahli, Ceyhan; Gerges, Meri; Starkova, Natalia; Starkov, Anatoly A; Jové, Mariona; Portero-Otin, Manuel; Launay, Nathalie; Pujol, Aurora; Kaidery, Navneet Ammal; Thomas, Bobby; Tampellini, Davide; Beal, M Flint; Dumont, Magali

2014-07-15

Methylene blue (MB, methylthioninium chloride) is a phenothiazine that crosses the blood brain barrier and acts as a redox cycler. Among its beneficial properties are its abilities to act as an antioxidant, to reduce tau protein aggregation and to improve energy metabolism. These actions are of particular interest for the treatment of neurodegenerative diseases with tau protein aggregates known as tauopathies. The present study examined the effects of MB in the P301S mouse model of tauopathy. Both 4 mg/kg MB (low dose) and 40 mg/kg MB (high dose) were administered in the diet ad libitum from 1 to 10 months of age. We assessed behavior, tau pathology, oxidative damage, inflammation and numbers of mitochondria. MB improved the behavioral abnormalities and reduced tau pathology, inflammation and oxidative damage in the P301S mice. These beneficial effects were associated with increased expression of genes regulated by NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE), which play an important role in antioxidant defenses, preventing protein aggregation, and reducing inflammation. The activation of Nrf2/ARE genes is neuroprotective in other transgenic mouse models of neurodegenerative diseases and it appears to be an important mediator of the neuroprotective effects of MB in P301S mice. Moreover, we used Nrf2 knock out fibroblasts to show that the upregulation of Nrf2/ARE genes by MB is Nrf2 dependent and not due to secondary effects of the compound. These findings provide further evidence that MB has important neuroprotective effects that may be beneficial in the treatment of human neurodegenerative diseases with tau pathology. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pharmacogenetics: progress, pitfalls and clinical potential for coronary heart disease.

PubMed

Humphries, Steve E; Hingorani, Aroon

2006-02-01

Much has been written about the potential of pharmacogenetic testing to inform therapy based on an individual's genetic makeup, and to decide the most effective choice of available drugs, or to avoid dangerous side effects. Currently, there is little hard data for either in the field of cardiovascular disease. The usual approach has been opportunistic use of drug trials in unrelated patients, and to look for differences in response or outcome by "candidate gene" genotype, for example genes coding for drug metabolising enzymes (activators and metabolisers), and enzymes and receptors involved in lipid metabolism, adrenergic response, etc. As with all association studies, initially promising results have often failed the test of replication in larger studies, and the relationship between the CETP Taq-I variant and response to statins has now been disproved. The strongest data to date is the report [Chasman, D.I., Posada, D., Subrahmanyan, L., Cook, N.R., Stanton Jr., V.P., Ridker, P.M., 2004. Pharmacogenetic study of statin therapy and cholesterol reduction. J. Am. Med. Assoc. 291, 2821-2827] of a poorer cholesterol-lowering response to Pravastatin in the 7% of patients carrying a certain haplotype of the HMG CoA reductase gene (14% fall versus 19%), but if this is overcome simply by a higher dose, it is of little clinical relevance. Currently, the best example of avoiding side effects is determining genotype at the CYP2C9 locus with respect of warfarin treatment, since carriers for functional variants (>20% of the population) require lower doses for optimal anticoagulation, and homozygotes, although rare, may well experience serious bleeding if given a usual dose. The full potential of this field will only be realised with much further work.

Dose-related gene expression changes in forebrain following acute, low-level chlorpyrifos exposure in neonatal rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ray, Anamika; Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078; Liu Jing

2010-10-15

Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 h following acute CPF exposure in 7-day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following either one of the four CPF dosages studied (546, 505, 522, and 3,066 genes with 0.1, 0.5, 1.0 and 2.0 mg/kg CPF). Genes were grouped according to dose-related expression patterns using K-means clusteringmore » while gene networks and canonical pathways were evaluated using Ingenuity Pathway Analysis (registered) . Twenty clusters were identified and differential expression of selected genes was verified by RT-PCR. The four largest clusters (each containing from 276 to 905 genes) constituted over 50% of all differentially expressed genes and exhibited up-regulation following exposure to the highest dosage (2 mg/kg CPF). The total number of gene networks affected by CPF also rose sharply with the highest dosage of CPF (18, 16, 18 and 50 with 0.1, 0.5, 1 and 2 mg/kg CPF). Forebrain cholinesterase (ChE) activity was significantly reduced (26%) only in the highest dosage group. Based on magnitude of dose-related changes in differentially expressed genes, relative numbers of gene clusters and signaling networks affected, and forebrain ChE inhibition only at 2 mg/kg CPF, we focused subsequent analyses on this treatment group. Six canonical pathways were identified that were significantly affected by 2 mg/kg CPF (MAPK, oxidative stress, NF{Kappa}B, mitochondrial dysfunction, arylhydrocarbon receptor and adrenergic receptor signaling). Evaluation of different cellular functions of the differentially expressed genes suggested changes related to olfactory receptors, cell adhesion/migration, synapse/synaptic transmission and transcription/translation. Nine genes were differentially affected in all four CPF dosing groups. We conclude that the most robust, consistent changes in differential gene expression in neonatal forebrain across a range of acute CPF dosages occurred at an exposure level associated with the classical marker of OP toxicity, AChE inhibition. Disruption of multiple cellular pathways, in particular cell adhesion, may contribute to the developmental neurotoxicity potential of this pesticide.« less

Genetic Control of the Trigger for the G2/M Checkpoint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hall, Eric J.; Smilenov, Lubomir B.; Young, Erik F.

The work undertaken in this project addressed two seminal areas of low dose radiation biology that are poorly understood and controversial. These areas are the challenge to the linear-no-threshold (LNT) paradigm at low doses of radiation and, the fundamental elements of radiation bystander effect biology Genetic contributions to low dose checkpoint engagement: The LNT paradigm is an extrapolation of known, measured cancer induction endpoints. Importantly, data for lower doses is often not available. Debatably, radiation protection standards have been introduced which are prudently contingent on the adherence of cancer risk to the established trend seen at higher doses. Intriguing findingsmore » from other labs have hinted at separate DNA damage response programs that engage at low or high levels of radiation. Individual radiation sensitivity commensurate with hemizygosity for a radiation sensitivity gene has been estimated at 1-2% in the U.S.. Careful interrogation of the DNA damage response at low doses of radiation became important and served as the basis for this grant. Several genes were tested in combinations to determine if combined haploinsufficiency for multiple radiosensitizing genes could render a cell more sensitive to lower levels of acute radiation exposure. We measured a classical radiation response endpoint, cell cycle arrest prior to mitosis. Mouse embryo fibroblasts were used and provided a uniform, rapidly dividing and genetically manipulable population of study. Our system did not report checkpoint engagement at acute doses of gamma rays below 100 mGy. The system did report checkpoint engagement reproducibly at 500 mGy establishing a threshold for activation between 100 and 500 mGy. Engagement of the checkpoint was ablated in cells nullizygous for ATM but was otherwise unperturbed in cells combinatorially haploinsufficient for ATM and Rad9, ATM and PTEN or PTEN and Rad9. Taken together, these experiments tell us that, in a sensitive fibroblast culture system, the engagement of the G2/M checkpoint only occurs at doses where most of the cells are bound for mitotic catastrophe. Further, compound haploinsufficiency of various radiosensitizing genes does not impact the threshold of activation. The experiments confirm a threshold of activation for the G2/M checkpoint, hinting at two separate radiation response programs acting below and above this threshold. Small RNA transfer in bystander effect biology: Small regulatory RNA molecules have now risen in prominence and utility. Specific examples are small interfering RNAs (siRNA) which are employed in cell level expression ablation projects and micro-RNAs (miRNA) which are a pool of short transcription products which serve to modulate the expression of other transcripts emerging from the genome in a meta-regulatory fine tuning of gene expression. The existing tenets of bystander effect radiation biology involve the communication of inflammatory mediators or direct intercellular communication of reactive oxygen/nitrogen species in cell-to-cell communicative organelles called gap junctions. By ablating gap junctions, reducing the ROS/inflammatory cytokine expression one can attenuate bystander effect signaling in cell culture systems. We hypothesized that miRNAs are a competent intercellular communication molecule and therefore a possible component of the bystander response. This view is supported by the observation that miRNA are secreted from cells in exosomes found in the circulation. This circulating pool reports disease type and severity in humans. We proposed use of microbeam irradiation technology at our facilities and enhancement of this capability with a new sorting technology which would allow us to sort irradiated and non-irradiated cells with absolute fidelity. Pursuing direct quantitative transfer assessment, we succeeded in designing and constructing a new add-on sorting appliance which harmonized with our existing instruments. The sorter allowed us to gently sort single fluorescently labeled cells. The plans for this appliance were published and are now available for use in other laboratories for single-cell analyses. Our microfluidic cell sorting modality is being integrated into subsequent microbeam irradiation experiments that are planned and ongoing. We generated and irradiated pools of specially engineered Donor-Recipient cell lines in co-culture that would report a small RNA transfer event by modulation of fluorescent protein expression. Both induction and reciprocal silencing designs were tested. We observed elevation of miRNA/siRNA transfer in response to radiation at doses of 5Gy in experiments to date. The reproducibility of these findings has not been good. Future studies will involve refinement of the reporting systems and a decrease in acute dose of radiation used to determine the lowest dose at which miRNA transfer between cells contributes to radiation bystander effect biology.« less

Non-thermal plasma treatment diminishes fungal viability and up-regulates resistance genes in a plant host.

PubMed

Panngom, Kamonporn; Lee, Sang Hark; Park, Dae Hoon; Sim, Geon Bo; Kim, Yong Hee; Uhm, Han Sup; Park, Gyungsoon; Choi, Eun Ha

2014-01-01

Reactive oxygen and nitrogen species can have either harmful or beneficial effects on biological systems depending on the dose administered and the species of organism exposed, suggesting that application of reactive species can possibly produce contradictory effects in disease control, pathogen inactivation and activation of host resistance. A novel technology known as atmospheric-pressure non-thermal plasma represents a means of generating various reactive species that adversely affect pathogens (inactivation) while simultaneously up-regulating host defense genes. The anti-microbial efficacy of this technology was tested on the plant fungal pathogen Fusarium oxysporum f.sp. lycopersici and its susceptible host plant species Solanum lycopercicum. Germination of fungal spores suspended in saline was decreased over time after exposed to argon (Ar) plasma for 10 min. Although the majority of treated spores exhibited necrotic death, apoptosis was also observed along with the up-regulation of apoptosis related genes. Increases in the levels of peroxynitrite and nitrite in saline following plasma treatment may have been responsible for the observed spore death. In addition, increased transcription of pathogenesis related (PR) genes was observed in the roots of the susceptible tomato cultivar (S. lycopercicum) after exposure to the same Ar plasma dose used in fungal inactivation. These data suggest that atmospheric-pressure non-thermal plasma can be efficiently used to control plant fungal diseases by inactivating fungal pathogens and up-regulating mechanisms of host resistance.

Endothelial responses of magnesium and other alloying elements in magnesium-based stent materials

PubMed Central

Zhao, Nan; Zhu, Donghui

2016-01-01

Biodegradable tailored magnesium (Mg) alloys are some of the most promising scaffolds for cardiovascular stents. During the course of degradation after implantation, all the alloying elements in the scaffold will be released to the surrounding vascular tissues. However, fundamental questions regarding the toxicity of alloying elements towards vascular cells, the maximum amount of each element that could be used in alloy design, or how each of the alloying elements affects vascular cellular activity and gene expression, are still not fully answered. This work systematically addressed these questions by revealing how application of different alloying elements commonly used in Mg stent materials influences several indices of human endothelial cell health, i.e., viability, proliferations, cytoskeletal reorganizations, migration, and the gene expression profile. The overall cell viability and proliferation showed a decreasing trend with increasing concentrations of the ions, and the half maximal effective concentrations (EC50) for each element were determined. When applied at a low concentration of around 10 mM, Mg had no adverse effects but improved cell proliferation and migration instead. Mg ions also altered endothelial gene expression significantly in a dose dependent manner. Most of the changed genes are related to angiogenesis and the cell adhesion signaling pathways. Findings from this work provide useful information on maximum safe doses of these ions for endothelial cells, endothelial responses towards these metal ions, and some guidance for future Mg stent design. PMID:25363018

Computational Model of the Modulation of Gene Expression Following DNA Damage

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Dicello, J. F.; Nikjoo, H.; Cherubini, R.

2002-01-01

High linear energy transfer (LET) radiation, such as heavy ions or neutrons, has an increased biological effectiveness compared to X rays for gene mutation, genomic instability, and carcinogenesis. In the traditional paradigm, mutations or chromosomal aberrations are causative of late effects. However, in recent years experimental evidence has demonstrated the important role of the description of the modification of gene expression by radiation in understanding the mechanisms of radiation action. In this report, approaches are discussed to the mathematical description of mRNA and protein expression kinetics following DNA damage. Several hypotheses for models of radiation modulation of protein expression are discussed including possible non-linear processes that evolve from the linear dose responses that follow the initial DNA damage produced by radiation.

Impact of intramammary treatment on gene expression profiles in bovine Escherichia coli mastitis.

PubMed

Sipka, Anja; Klaessig, Suzanne; Duhamel, Gerald E; Swinkels, Jantijn; Rainard, Pascal; Schukken, Ynte

2014-01-01

Clinical mastitis caused by E. coli accounts for significant production losses and animal welfare concerns on dairy farms worldwide. The benefits of therapeutic intervention in mild to moderate cases are incompletely understood. We investigated the effect of intramammary treatment with cefapirin alone or in combination with prednisolone on gene expression profiles in experimentally-induced E. coli mastitis in six mid-lactating Holstein Friesian cows. Cows were challenged with E. coli in 3 quarters and received 4 doses of 300 mg cefapirin in one quarter and 4 doses of 300 mg cefapirin together with 20 mg prednisolone in another quarter. At 24 h (n = 3) or 48 h (n = 3) post-challenge, tissue samples from control and treated quarters were collected for microarray analysis. Gene expression analysis of challenged, un-treated quarters revealed an up-regulation of transcripts associated with immune response functions compared to un-challenged quarters. Both treatments resulted in down-regulation of these transcripts compared to challenged, un-treated quarters most prominently for genes representing Chemokine and TLR-signaling pathways. Gene expression of Lipopolysaccharide Binding Protein (LBP), CCL2 and CXCL2 were only significantly down-regulated in cefapirin-prednisolone-treated quarters compared to un-treated controls. Down-regulation of chemokines was further confirmed on the basis of protein levels in milk whey for CXCL1, CXCL2 and CXCL8 in both treatments with a greater decrease in cefapirin-prednisolone-treated quarters. The data reveal a significant effect of treatment on cell recruitment with a more pronounced effect in cefapirin-prednisolone treated quarters. Provided a rapid bacteriological clearance, combination therapy may prevent neutrophil-induced tissue damage and promote recovery of the gland.

Effects of different cytokines on immune responses of rainbow trout in a virus DNA vaccination model

PubMed Central

Cao, Yongsheng; Zhang, Qiya; Xu, Liming; Li, Shaowu; Wang, Di; Zhao, Jingzhuang; Liu, Hongbai; Feng, Jian; Lu, Tongyan

2017-01-01

Seven rainbow trout cytokine genes (interleukin (IL)-2, IL-8, IL-15, IL-17, IL-1β, intracellular interferon (iIFN) 1a, and IFN-γ2) were evaluated for their adjuvant effects on a DNA vaccine, called pG, containing the glycoprotein gene of infectious hematopoietic necrosis virus (IHNV). Distinct DNA constructs in expression plasmid pcDNA3.1 encoding a cytokine gene were generated. Immunofluorescence assays in rainbow trout gonadal cells demonstrated successful protein expression from all these constructs. Subsequently, fish were immunized with pG alone or together with a cytokine expression plasmid. Results showed that each cytokine plasmids at an appropriate dose showed notable effects on immune gene expression. IL-17 and IFN-γ2 can enhance early specific IgM response. All cytokines, except IL-8, can benefit initial neutralizing antibody (NAb) titers. At 35 days post immunization (dpi), NAb titers of fish immunized with pG and IL-2, iIFN1a, or IFN-γ2 plasmids remained at high levels (1:160). NAb titers of fish immunized with pG alone decreased to 1:40. IL-8 or IL-1β can enhance antigen-specific proliferative T-cell responses at 14 dpi. At 28 dpi, coinjection of pG with IL-2, IL-8, IL-15, or IL-17 plasmids induced considerably stronger lymphocyte proliferation than that with injection of pG alone. All cytokine plasmids delivered with pG plasmid enhanced protection of trout against IHNV-mediated mortality. These results indicate that the type and dose of trout cytokine genes injected into fish affect quality of immune response to DNA vaccination. PMID:29348820

Association between an Alzheimer's Disease-Related Index and APOE ε4 Gene Dose.

PubMed

Schraml, Frank; Chen, Kewei; Ayutyanont, Napatkamon; Auttawut, Roontiva; Langbaum, Jessica B S; Lee, Wendy; Liu, Xiaofen; Bandy, Dan; Reeder, Stephanie Q; Alexander, Gene E; Caselli, Richard J; Fleisher, Adam S; Reiman, Eric M

2013-01-01

We introduced a hypometabolic convergence index (HCI) to characterize in a single measurement the extent to which a person's fluorodeoxyglucose positron emission tomogram (FDG PET) corresponds to that in Alzheimer's disease (AD). Apolipoprotein E ε4 (APOE ε4) gene dose is associated with three levels of risk for late-onset AD. We explored the association between gene dose and HCI in cognitively normal ε4 homozygotes, heterozygotes, and non-carriers. An algorithm was used to characterize and compare AD-related HCIs in cognitively normal individuals, including 36 ε4 homozygotes, 46 heterozygotes, and 78 non-carriers. These three groups differed significantly in their HCIs (ANOVA, p = 0.004), and there was a significant association between HCIs and gene dose (linear trend, p = 0.001). The HCI is associated with three levels of genetic risk for late-onset AD. This supports the possibility of using a single FDG PET measurement to help in the preclinical detection and tracking of AD.

Involvement of nitrergic system in anticonvulsant effect of zolpidem in lithium-pilocarpine induced status epilepticus: Evaluation of iNOS and COX-2 genes expression.

PubMed

Eslami, Seyyed Majid; Ghasemi, Maryam; Bahremand, Taraneh; Momeny, Majid; Gholami, Mahdi; Sharifzadeh, Mohammad; Dehpour, Ahmad Reza

2017-11-15

This study aims to investigate the role of zolpidem in lithium-pilocarpine induced status epilepticus (SE) and probable mechanisms involved in seizure threshold alteration. In the present study, lithium chloride (127mg/kg) was administered 20h prior to pilocarpine (60mg/kg) to induce SE in adult male Wistar rats. Different doses of zolpidem (0.1, 1, 2, 5, 10mg/kg) were injected 30min before pilocarpine administration. Furthermore, to find out whether nitric oxide (NO) plays a role in the observed effect, L-arginine and L-NAME were injected 15min before zolpidem. Afterward, we identified the particular NO isoform mediating the effect of zolpidem by injecting aminoguanidine (AG) and 7-Nitroindazole (7-NI) 15min prior to zolpidem. Moreover, in both 6 and 24h after pilocarpine injection, experimental groups underwent hippocampectomy to evaluate cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes expression by quantitative reverse transcription-PCR (qRT-PCR). Pre-treatment with zolpidem significantly prevented the onset of SE in a dose-dependent manner. AG and L-NAME significantly potentiated the anticonvulsant effect of zolpidem while L-arginine inverted this effect. Our qRT-PCR exerted that there was a continuous elevation of iNOS and COX-2 genes expression over 6 and 24h after pilocarpine administration in SE and L-arginine+Zolpidem groups while in AG/L-NAME+Zolpidem and zolpidem groups this upregulation was prevented. Our study indicates that zolpidem prevents the onset of SE through inhibition of iNOS/COX-2 genes upregulation following lithium-pilocarpine administration. Consistent with our results, we suggest that iNOS activation could be probably upstream of COX-2 gene expression. Copyright © 2017 Elsevier B.V. All rights reserved.

Pyrethroid insecticide lambda-cyhalothrin induces hepatic cytochrome P450 enzymes, oxidative stress and apoptosis in rats.

PubMed

Martínez, María-Aránzazu; Ares, Irma; Rodríguez, José-Luis; Martínez, Marta; Roura-Martínez, David; Castellano, Victor; Lopez-Torres, Bernardo; Martínez-Larrañaga, María-Rosa; Anadón, Arturo

2018-08-01

This study aimed to examine in rats the effects of the Type II pyrethroid lambda-cyhalothrin on hepatic microsomal cytochrome P450 (CYP) isoform activities, oxidative stress markers, gene expression of proinflammatory, oxidative stress and apoptosis mediators, and CYP isoform gene expression and metabolism phase I enzyme PCR array analysis. Lambda-cyhalothrin, at oral doses of 1, 2, 4 and 8mg/kg bw for 6days, increased, in a dose-dependent manner, hepatic activities of ethoxyresorufin O-deethylase (CYP1A1), methoxyresorufin O-demethylase (CYP1A2), pentoxyresorufin O-depentylase (CYP2B1/2), testosterone 7α- (CYP2A1), 16β- (CYP2B1), and 6β-hydroxylase (CYP3A1/2), and lauric acid 11- and 12-hydroxylase (CYP4A1/2). Similarly, lambda-cyhalothrin (4 and 8mg/kg bw, for 6days), in a dose-dependent manner, increased significantly hepatic CYP1A1, 1A2, 2A1, 2B1, 2B2, 2E1, 3A1, 3A2 and 4A1 mRNA levels and IL-1β, NFκB, Nrf2, p53, caspase-3 and Bax gene expressions. PCR array analysis showed from 84 genes examined (P<0.05; fold change>1.5), changes in mRNA levels in 18 genes: 13 up-regulated and 5 down-regulated. A greater fold change reversion than 3-fold was observed on the up-regulated ALDH1A1, CYP2B2, CYP2C80 and CYP2D4 genes. Ingenuity Pathway Analysis (IPA) groups the expressed genes into biological mechanisms that are mainly related to drug metabolism. In the top canonical pathways, Oxidative ethanol degradation III together with Fatty Acid α-oxidation may be significant pathways for lambda-cyhalothrin. Our results may provide further understanding of molecular aspects involved in lambda-cyhalothrin-induced liver injury. Copyright © 2018. Published by Elsevier B.V.

Sublethal effects of acaricides and Nosema ceranae infection on immune related gene expression in honeybees.

PubMed

Garrido, Paula Melisa; Porrini, Martín Pablo; Antúnez, Karina; Branchiccela, Belén; Martínez-Noël, Giselle María Astrid; Zunino, Pablo; Salerno, Graciela; Eguaras, Martín Javier; Ieno, Elena

2016-04-26

Nosema ceranae is an obligate intracellular parasite and the etiologic agent of Nosemosis that affects honeybees. Beside the stress caused by this pathogen, honeybee colonies are exposed to pesticides under beekeeper intervention, such as acaricides to control Varroa mites. These compounds can accumulate at high concentrations in apicultural matrices. In this work, the effects of parasitosis/acaricide on genes involved in honeybee immunity and survival were evaluated. Nurse bees were infected with N. ceranae and/or were chronically treated with sublethal doses of coumaphos or tau-fluvalinate, the two most abundant pesticides recorded in productive hives. Our results demonstrate the following: (1) honeybee survival was not affected by any of the treatments; (2) parasite development was not altered by acaricide treatments; (3) coumaphos exposure decreased lysozyme expression; (4) N. ceranae reduced levels of vitellogenin transcripts independently of the presence of acaricides. However, combined effects among stressors on imagoes were not recorded. Sublethal doses of acaricides and their interaction with other ubiquitous parasites in colonies, extending the experimental time, are of particular interest in further research work.

Immunostimulatory effects of natural human interferon-alpha (huIFN-alpha) on carps Cyprinus carpio L.

PubMed

Watanuki, Hironobu; Chakraborty, Gunimala; Korenaga, Hiroki; Kono, Tomoya; Shivappa, R B; Sakai, Masahiro

2009-10-15

Human interferon-alpha (huIFN-alpha) is an important immunomodulatory substance used in the treatment and prevention of numerous infectious and immune-related diseases in animals. However, the immunostimulatory effects of huIFN-alpha in fish remain to be investigated. In the current study, the immune responses of the carp species Cyprinus carpio L. to treatment with huIFN-alpha were analyzed via measurement of superoxide anion production, phagocytic activity and the expression of cytokine genes including interleukin-1beta, tumor necrosis factor-alpha and interleukin 10. Low doses of huIFN-alpha were administered orally once a day for 3 days, and sampling was carried out at 1, 3 and 5 days post-treatment. Our results indicate that a low dose of huIFN-alpha significantly increased phagocytic activity and superoxide anion production in the carp kidney. The huIFN-alpha-treated fish also displayed a significant upregulation in cytokine gene expression. The current study demonstrates the stimulatory effects of huIFN-alpha on the carp immune system and highlights the immunomodulatory role of huIFN-alpha in fish.

Performance of urinary and gene expression biomarkers in detecting the nephrotoxic effects of melamine and cyanuric acid following diverse scenarios of co-exposure

PubMed Central

Bandele, Omari; Camacho, Luísa; Ferguson, Martine; Reimschuessel, Renate; Stine, Cynthia; Black, Thomas; Olejnik, Nicholas; Keltner, Zachary; Scott, Michael; Gamboa da Costa, Gonçalo; Sprando, Robert

2013-01-01

Although standard nephrotoxicity assessments primarily detect impaired renal function, KIM-1, clusterin, NGAL, osteopontin and TIMP-1 were recently identified biomarkers proposed to indicate earlier perturbations in renal integrity. The recent adulteration of infant and pet food with melamine (MEL) and structurally-related compounds revealed that co-ingestion of MEL and cyanuric acid (CYA) could form melamine–cyanurate crystals which obstruct renal tubules and induce acute renal failure. This study concurrently evaluated the ability of multiplexed urinary biomarker immunoassays and biomarker gene expression analysis to detect nephrotoxicity in F344 rats co-administered 60 ppm each of MEL and CYA in feed or via gavage for 28 days. The biomarkers were also evaluated for the ability to differentiate the effects of the compounds when co-administered using diverse dosing schedules (i.e., consecutive vs. staggered gavage) and dosing matrixes (i.e., feed vs. gavage). Our results illustrate the ability of both methods to detect and differentiate the severity of adverse effects in the staggered and consecutive gavage groups at much lower doses than previously observed in animals co-exposed to the compounds in feed. We also demonstrate that these urinary biomarkers outperform traditional diagnostic methods and represent a powerful, non-invasive indicator of chemical-induced nephrotoxicity prior to the onset of renal dysfunction. PMID:23022069

Clinical dose effect and functional consequences of R92Q in two families presenting with a TRAPS/PFAPA-like phenotype.

PubMed

Grandemange, Sylvie; Cabasson, Sébastien; Sarrabay, Guillaume; Pène, Jérôme; Rittore, Cécile; Sanchez, Elodie; Chastang, Marie-Caroline; Guyon, Gaël; Pillet, Pascal; Touitou, Isabelle

2017-03-01

TNF receptor-associated syndrome (TRAPS) is a dominantly inherited autoinflammatory condition caused by mutations in the TNFRSF1A gene. The mechanism underlying the variable expressivity of the common variant R92Q (rs4149584; c.362G>A; p.Arg121Gln) is unclear and is of critical importance for patient care and genetic counseling. This study evaluated the impact of the number of R92Q mutations in two unique unrelated families. Two patients with undefined but clear autoinflammatory symptoms were referred for genetic diagnosis. Blood samples were collected from the available family members to screen autoinflammatory genes and assess key steps of the TNFR1-mediated signaling pathway using flow cytometry and ex vivo culture. R92Q homozygosity was demonstrated for the two probands. In family 1, the segregation analysis revealed TRAPS-like symptoms in all carriers, with a more severe presentation in the proband, whereas in family 2, the heterozygous parents were totally asymptomatic, suggesting recessive transmission. Functional studies revealed a nonclassical pathogenesis of TRAPS in the two probands and suggested a compensatory mechanism without clear dose effect. We observed for the first time a possible clinical dose effect of R92Q. This work highlights the importance of familial studies to reconcile the contradictory reports published on the pathogenicity of this variant.

Low-power laser irradiation promotes the proliferation and osteogenic differentiation of human periodontal ligament cells via cyclic adenosine monophosphate

PubMed Central

Wu, Jyun-Yi; Chen, Chia-Hsin; Yeh, Li-Yin; Yeh, Ming-Long; Ting, Chun-Chan; Wang, Yan-Hsiung

2013-01-01

Retaining or improving periodontal ligament (PDL) function is crucial for restoring periodontal defects. The aim of this study was to evaluate the physiological effects of low-power laser irradiation (LPLI) on the proliferation and osteogenic differentiation of human PDL (hPDL) cells. Cultured hPDL cells were irradiated (660 nm) daily with doses of 0, 1, 2 or 4 J⋅cm−2. Cell proliferation was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the effect of LPLI on osteogenic differentiation was assessed by Alizarin Red S staining and alkaline phosphatase (ALP) activity. Additionally, osteogenic marker gene expression was confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR). Our data showed that LPLI at a dose of 2 J⋅cm−2 significantly promoted hPDL cell proliferation at days 3 and 5. In addition, LPLI at energy doses of 2 and 4 J⋅cm−2 showed potential osteogenic capacity, as it stimulated ALP activity, calcium deposition, and osteogenic gene expression. We also showed that cyclic adenosine monophosphate (cAMP) is a critical regulator of the LPLI-mediated effects on hPDL cells. This study shows that LPLI can promote the proliferation and osteogenic differentiation of hPDL cells. These results suggest the potential use of LPLI in clinical applications for periodontal tissue regeneration. PMID:23788285

Effect of tributyltin on antioxidant ability and immune responses of zebrafish (Danio rerio).

PubMed

Zhang, Chun-Nuan; Zhang, Ji-Liang; Ren, Hong-Tao; Zhou, Bian-Hua; Wu, Qiu-Jue; Sun, Ping

2017-04-01

Tributyltin (TBT) is a toxic compound released into aquatic ecosystems through antifouling paints. This study was designed to examine the effects of TBT on antioxidant ability and immune responses of zebrafish (Danio rerio). Three hundred sixty healthy zebrafish were randomly grouped into four groups and exposed to different doses of TBT (0, 1, 10 and 100ngL -1 ). At the end of 8 weeks, the fish were sampled, and antioxidant capability, immune parameters and immune-related genes were assessed. The results showed that with an increase in TBT dose, the concentration of malonaldehyde in the liver was significantly increased (p<0.05), whereas the activities of total superoxide dismutase, catalase and glutathione peroxidase were significantly decreased (p<0.05) compared to the control. The activity and expression of lysozyme and the content of immunoglobulin M were significantly decreased compared to those of the fish exposed to 0ngL -1 TBT (p<0.05). However, the expression of the HSP70, HSP90, tumor necrosis factor-α(TNF-α), interleukins (IL-1β, IL-6), and nuclear factor-kappa B p65 (NF-κ B p65) genes were all enhanced with an increase in TBT dose. The results indicated that TBT induced oxidative stress and had immunotoxic effects on zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

o-p′-DDT-mediated uterotrophy and gene expression in immature C57BL/6 mice and Sprague–Dawley rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwekel, Joshua C.; Forgacs, Agnes L.; Center for Integrative Toxicology, Michigan State University, East Lansing, MI

1,1,1-Trichloro-2,2-bis(2-chlorophenyl-4-chlorophenyl)ethane (o,p′-DDT) is an organochlorine pesticide and endocrine disruptor known to activate the estrogen receptor. Comprehensive ligand- and species-comparative dose- and time-dependent studies were conducted to systematically assess the uterine physiological, morphological and gene expression responses elicited by o,p′-DDT and ethynyl estradiol (EE) in immature ovariectomized C57BL/6 mice and Sprague–Dawley rats. Custom cDNA microarrays were used to identify conserved and divergent differential gene expression responses. A total of 1256 genes were differentially expressed by both ligands in both species, 559 of which exhibited similar temporal expression profiles suggesting that o,p′-DDT elicits estrogenic effects at high doses when compared to EE.more » However, 51 genes exhibited species-specific uterine expression elicited by o,p′-DDT. For example, carbonic anhydrase 2 exhibited species- and ligand-divergent expression as confirmed by quantitative real-time PCR. The identification of comparable temporal phenotypic responses linked to gene expression demonstrates that systematic comparative gene expression assessments are valuable for elucidating conserved and divergent estrogen signaling mechanisms in rodent uterotrophy. - Highlights: • o,p′-DDT and enthynyl estradiol (EE) both elicit uterotrophy in mice and rats. • o,p′-DDT and EE have different kinetics in uterine wet weight induction. • o,p′-DDT elicited stromal hypertrophy in rats but myometrial hypertrophy in mice. • 1256 genes were differentially expressed by both ligands in both species. • Only 51 genes had species-specific uterine expression.« less

Dose-specific transcriptional responses in thyroid tissue in mice after (131)I administration.

PubMed

Rudqvist, Nils; Schüler, Emil; Parris, Toshima Z; Langen, Britta; Helou, Khalil; Forssell-Aronsson, Eva

2015-03-01

In the present investigation, microarray analysis was used to monitor transcriptional activity in thyroids in mice 24 h after (131)I exposure. The aims of this study were to 1) assess the transcriptional patterns associated with (131)I exposure in normal mouse thyroid tissue and 2) propose biomarkers for (131)I exposure of the thyroid. Adult BALB/c nude mice were i.v. injected with 13, 130 or 260 kBq of (131)I and killed 24h after injection (absorbed dose to thyroid: 0.85, 8.5, or 17 Gy). Mock-treated mice were used as controls. Total RNA was extracted from thyroids and processed using the Illumina platform. In total, 497, 546, and 90 transcripts were regulated (fold change ≥1.5) in the thyroid after 0.85, 8.5, and 17 Gy, respectively. These were involved in several biological functions, e.g. oxygen access, inflammation and immune response, and apoptosis/anti-apoptosis. Approximately 50% of the involved transcripts at each absorbed dose level were dose-specific, and 18 transcripts were commonly detected at all absorbed dose levels. The Agpat9, Plau, Prf1, and S100a8 gene expression displayed a monotone decrease in regulation with absorbed dose, and further studies need to be performed to evaluate if they may be useful as dose-related biomarkers for 131I exposure. Distinct and substantial differences in gene expression and affected biological functions were detected at the different absorbed dose levels. The transcriptional profiles were specific for the different absorbed dose levels. We propose that the Agpat9, Plau, Prf1, and S100a8 genes might be novel potential absorbed dose-related biomarkers to (131)I exposure of thyroid. During the recent years, genomic techniques have been developed; however, they have not been fully utilized in nuclear medicine and radiation biology. We have used RNA microarrays to investigate genome-wide transcriptional regulations in thyroid tissue in mice after low, intermediate, and high absorbed doses from (131)I exposure in vivo. Using this approach, we have identified novel biological responses and potential absorbed dose-related biomarkers to (131)I exposure. Our research shows the importance of embracing technological advances and multi-disciplinary collaboration in order to apply them in radiation therapy, nuclear medicine, and radiation biology. This work may contribute with new knowledge of potential normal tissue effects or complications that may occur after exposure to ionizing radiation in diagnostic and therapeutic nuclear medicine, and due to radioactive fallout or accident with radionuclide spread. Copyright © 2014 Elsevier Inc. All rights reserved.

Co-expression of antioxidant enzymes with expression of p53, DNA repair, and heat shock protein genes in the gamma ray-irradiated hermaphroditic fish Kryptolebias marmoratus larvae.

PubMed

Rhee, Jae-Sung; Kim, Bo-Mi; Kim, Ryeo-Ok; Seo, Jung Soo; Kim, Il-Chan; Lee, Young-Mi; Lee, Jae-Seong

2013-09-15

To investigate effects of gamma ray irradiation in the hermaphroditic fish, Kryptolebias marmoratus larvae, we checked expression of p53, DNA repair, and heat shock protein genes with several antioxidant enzyme activities by quantitative real-time RT-PCR and biochemical methods in response to different doses of gamma radiation. As a result, the level of gamma radiation-induced DNA damage was initiated after 4Gy of radiation, and biochemical and molecular damage became substantial from 8Gy. In particular, several DNA repair mechanism-related genes were significantly modulated in the 6Gy gamma radiation-exposed fish larvae, suggesting that upregulation of such DNA repair genes was closely associated with cell survival after gamma irradiation. The mRNA expression of p53 and most hsps was also significantly upregulated at high doses of gamma radiation related to cellular damage. This finding indicates that gamma radiation can induce oxidative stress with associated antioxidant enzyme activities, and linked to modulation of the expression of DNA repair-related genes as one of the defense mechanisms against radiation damage. This study provides a better understanding of the molecular mode of action of defense mechanisms upon gamma radiation in fish larvae. Copyright © 2013 Elsevier B.V. All rights reserved.

Trichostatin A increases SMN expression and survival in a mouse model of spinal muscular atrophy

PubMed Central

Avila, Amy M.; Burnett, Barrington G.; Taye, Addis A.; Gabanella, Francesca; Knight, Melanie A.; Hartenstein, Parvana; Cizman, Ziga; Di Prospero, Nicholas A.; Pellizzoni, Livio; Fischbeck, Kenneth H.; Sumner, Charlotte J.

2007-01-01

The inherited motor neuron disease spinal muscular atrophy (SMA) is caused by mutation of the telomeric survival motor neuron 1 (SMN1) gene with retention of the centromeric SMN2 gene. We sought to establish whether the potent and specific hydroxamic acid class of histone deacetylase (HDAC) inhibitors activates SMN2 gene expression in vivo and modulates the SMA disease phenotype when delivered after disease onset. Single intraperitoneal doses of 10 mg/kg trichostatin A (TSA) in nontransgenic and SMA model mice resulted in increased levels of acetylated H3 and H4 histones and modest increases in SMN gene expression. Repeated daily doses of TSA caused increases in both SMN2-derived transcript and SMN protein levels in neural tissues and muscle, which were associated with an improvement in small nuclear ribonucleoprotein (snRNP) assembly. When TSA was delivered daily beginning on P5, after the onset of weight loss and motor deficit, there was improved survival, attenuated weight loss, and enhanced motor behavior. Pathological analysis showed increased myofiber size and number and increased anterior horn cell size. These results indicate that the hydroxamic acid class of HDAC inhibitors activates SMN2 gene expression in vivo and has an ameliorating effect on the SMA disease phenotype when administered after disease onset. PMID:17318264

Neuroprotective effects of diazoxide and its antagonism by glibenclamide in pyramidal neurons of rat hippocampus subjected to ischemia-reperfusion-induced injury.

PubMed

Zarch, Anoushiravan Vakili; Toroudi, Hamidreza Pazoki; Soleimani, Mansooreh; Bakhtiarian, Azam; Katebi, Majid; Djahanguiri, Bijan

2009-01-01

Mitochondrial ATP-sensitive potassium channel opener, diazoxide, is shown to have protective effect on the heart and brain following ischemia-reperfusion-induced injury (IR/II). However, the detailed effect of diazoxide and its antagonist on neuronal death, mitochondrial changes, and apoptosis in cerebral IR/II has not fully studied. IR/II was induced in rats by the 4-vessel occlusion model. Neuronal cell death and mitochondrial changes in CA1-CA4 pyramidal cells of the hippocampus were studied by light and electron microscopy, respectively. Apoptosis was assessed by measuring the amount of protein expressed by Bax and Bcl-2 genes. In light microscopy studies, the number of total and normal cells were increased only following 18 mg/kg of diazoxide. Lower doses (2 and 6 mg/kg) failed to change the cell numbers. All three doses of glibenclamide (1, 5, and 25 mg/kg) decreased the number of total and normal cell populations. In electron microscopy studies, different doses of diazoxide and glibenclamide prevented and aggravated the IR-induced morphological changes, respectively. Western blot analysis showed that diazoxide and glibenclamide inhibited and enhanced Bax protein expression respectively. Regarding Bcl-2 expression, only diazoxide showed a significant enhancement of gene expression. In conclusion, the results show that diazoxide can exhibit neuroprotective effects against IR/II in hippocampal regions, possibly through the opening of mitochondrial ATP-sensitive K(+) channels.

Zoledronic acid overcomes chemoresistance by sensitizing cancer stem cells to apoptosis.

PubMed

Rouhrazi, H; Turgan, N; Oktem, G

2018-01-01

Unlike low tumorigenic bulk tumor cells (non-CSCs), cancer stem cells (CSCs) are a subset of tumor cells that can self-renew and differentiate into different cancer subtypes. CSCs are considered responsible for tumor recurrence, distant metastasis, angiogenesis, and drug or radiation resistance. CSCs also are resistant to apoptosis. Zoledronic acid (ZA) is a third generation bisphosphonate that reduces cell proliferation and exhibits anti-tumor effects by inducing cell death in some malignancies; however, the effects of ZA on CSCs are unclear. We investigated the anti-cancer effects of ZA on two epithelial cancer cell lines, prostate DU-145 and breast MCF7, focusing primarily on induction and activation of apoptosis. Cluster of differentiation (CD) 133 + /CD44 + prostate CSCs and CD 44 + /CD24 breast CSCs were isolated from the DU-145 human prostate cancer and MCF-7 human breast cancer cell lines, respectively, using FACSAria flow cytometry cell sorting. CSCs and non-CSCs were exposed to increasing concentrations of ZA for 24, 48 and 72 h to determine the IC 50 dose. Annexin-V assay for detecting cell death and cell cycle was performed using the Muse™ Cell Analyzer. Prostate CSCs and non-CSCs were assayed by quantitative reverse transcription PCR (qRT-PCR) array for detecting 84 key apoptosis related genes. Gene regulation at the protein level was investigated by immunofluorescence. ZA caused a dose- and time-dependent decrease in cell viability. Treatment with ZA resulted in a concomitant increase in apoptosis and cell cycle arrest at S-phase in CSCs. Significant over/under-expressions were detected in seven of the genes of ZA-treated DU-145 CSCs cells. Expressions of CASP9, CASP4, BAX and BAD genes increased, while the expressions of BIRC3, BIRC2 and BCL2 genes decreased. In the DU-145 non-CSCs, five genes exhibited changes in gene expression after ZA treatment, two exhibited increased expression (CASP7 and BAD) and three exhibited decreased expression (BIRC3, BIRC2 and BCL2). ZA caused cell death of drug resistant breast MCF-7 and prostate DU-145 cancer stem cells by activating apoptosis. ZA can facilitate the intrinsic pathway of apoptosis in human prostate CSCs by down-regulating anti-apoptotic genes and up-regulating pro-apoptotic genes. ZA may be an effective therapeutic agent for targeting chemoresistance in CSCs.

Effect of randomized serum progesterone concentration on secretory endometrial histologic development and gene expression.

PubMed

Young, Steven L; Savaris, Ricardo F; Lessey, Bruce A; Sharkey, Andrew M; Balthazar, Ursula; Zaino, Richard J; Sherwin, Robert A; Fritz, Marc A

2017-09-01

What doses of secretory phase progesterone (P) in women are associated with altered endometrial structure and/or function? Consistently delayed histological maturation was seen at the lowest tested daily P dose (2.5 mg), whereas consistently altered functional response, as reflected by microarray analysis of gene expression was seen at both the 5 and 2.5 mg doses. Progesterone is absolutely required for normal embryo implantation and pregnancy survival. Progesterone supplementation is beneficial in ART cycles. In this case-control experimental trial, 46 healthy young female volunteers (age 19-34) underwent a single modeled endometrial cycle after GnRH down-regulation or monitored in natural cycles. In a university hospital, modeled cycles were obtained by GnRH agonist down-regulation, transdermal estradiol (E2) (0.2 mg/d), and daily injections of P in oil for 10 days: 2.5 mg (n = 6), 5 mg (n = 6), 10 mg (n = 12) or 40 mg (n = 12), after the 10th day of E2. Ten healthy, ovulatory women were used as controls. Endometrial biopsies were obtained on the 10th day of P exposure, or urinary LH surge (in controls). Analysis included histological dating, serum progesterone levels, microarray analysis of the whole genome, RT-PCR, western blot and comparison with the GEO database. In endometrial biopsies, a morphological delay appears in the 2.5 mg/day of P group. Higher sub-physiological levels of P (≥5 mg/day) resulted in normal histology, but aberrant gene expression. P levels required for consistent histological delay were lower than those in all ovulatory women. Gene expression abnormalities occurred at higher sub-physiological P concentrations, without a change in histology, a functional-morphological disassociation. The expression of some endometrial receptivity-associated genes appeared multiphasic, with peak or nadir of mean or median expression levels between the lowest and highest doses, suggesting sustained supraphysiological doses seen in ART treatment cycles may not be optimal. GEO DataSets ID: 200056980; GSE 56980. These results were obtained in fertile women, who may respond differently from infertile subjects. The dose of P required for normal endometrial structure (5 mg/day) corresponds to a P concentration well below that seen in ovulatory women, suggesting that persistently delayed mid-secretory histology cannot be solely due to inadequate P concentrations in an ovulatory cycle. Endometrial gene expression is differentially regulated by different doses of progesterone. The apparent multiphasic response of some genes to P dose suggests the possibility that P concentration kinetics may play a role in normal endometrial preparation for receptivity. These findings strongly confirm that histologic development is not a reliable measure of endometrial P action. Supported by The Eunice Kennedy Shriver National Institute for Child Health and Disease, National Institute of Health, USA (NICHD/NIH) (R01HD067721 and U54HD30476; SLY and BAL) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) 240239/2012-1 (RFS). All authors have no competing interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Impact of Blood Type, Functional Polymorphism (T-1676C) of the COX-1 Gene Promoter and Clinical Factors on the Development of Peptic Ulcer during Cardiovascular Prophylaxis with Low-Dose Aspirin

PubMed Central

Wang, Pin-Yao; Chen, Hsiu-Ping; Chen, Angela; Tsay, Feng-Woei; Kao, Sung-Shuo; Peng, Nan-Jing; Tseng, Hui-Hwa; Hsu, Ping-I

2014-01-01

Aims. To investigate the impact of blood type, functional polymorphism (T-1676C) of the COX-1 gene promoter, and clinical factors on the development of peptic ulcer during cardiovascular prophylaxis with low-dose aspirin. Methods. In a case-control study including 111 low-dose aspirin users with peptic ulcers and 109 controls (asymptomatic aspirin users), the polymorphism (T-1676C) of the COX-1 gene promoter was genotyped, and blood type, H pylori status, and clinical factors were assessed. Results. Univariate analysis showed no significant differences in genotype frequencies of the COX-1 gene at position -1676 between the peptic ulcer group and control group. Multivariate analysis revealed that blood type O, advanced age, history of peptic ulcer, and concomitant use of NSAID were the independent risk factors for the development of peptic ulcer with the odds ratios of the 2.1, 3.1, 27.6, and 2.9, respectively. Conclusion. The C-1676T polymorphism in the COX-1 gene promoter is not a risk factor for ulcer formation during treatment with low-dose aspirin. Blood type O, advanced age, history of peptic ulcer, and concomitant use of NSAID are of independent significance in predicting peptic ulcer development during treatment with low-dose aspirin. PMID:25243161

Dietary Aloe Vera Supplementation Improves Facial Wrinkles and Elasticity and It Increases the Type I Procollagen Gene Expression in Human Skin in vivo

PubMed Central

Cho, Soyun; Lee, Serah; Lee, Min-Jung; Lee, Dong Hun; Won, Chong-Hyun; Kim, Sang Min

2009-01-01

Background No studies have yet been undertaken to determine the effect of aloe gel on the clinical signs and biochemical changes of aging skin. Objective We wanted to determine whether dietary aloe vera gel has anti-aging properties on the skin. Methods Thirty healthy female subjects over the age of 45 were recruited and they received 2 different doses (low-dose: 1,200 mg/d, high-dose: 3,600 mg/d) of aloe vera gel supplementation for 90 days. Their baseline status was used as a control. At baseline and at completion of the study, facial wrinkles were measured using a skin replica, and facial elasticity was measured by an in vivo suction skin elasticity meter. Skin samples were taken before and after aloe intake to compare the type I procollagen and matrix metalloproteinase 1 (MMP-1) mRNA levels by performing real-time RT-PCR. Results After aloe gel intake, the facial wrinkles improved significantly (p<0.05) in both groups, and facial elasticity improved in the lower-dose group. In the photoprotected skin, the type I procollagen mRNA levels were increased in both groups, albeit without significance; the MMP-1 mRNA levels were significantly decreased in the higher-dose group. Type I procollagen immunostaining was substantially increased throughout the dermis in both groups. Conclusion Aloe gel significantly improves wrinkles and elasticity in photoaged human skin, with an increase in collagen production in the photoprotected skin and a decrease in the collagen-degrading MMP-1 gene expression. However, no dose-response relationship was found between the low-dose and high-dose groups. PMID:20548848

Triiodothyronine modulates the expression of leptin and adiponectin in 3T3-L1 adipocytes

PubMed Central

de Oliveira, Miriane; Síbio, Maria Teresa De; Olimpio, Regiane Marques Castro; Moretto, Fernanda Cristina Fontes; Luvizotto, Renata de Azevedo Melo; Nogueira, Celia Regina

2015-01-01

Objective To study the effect of different doses of triiodothyronine on gene expression of the adipokines leptin and adiponectin, at different times, and to evaluate the difference in expression between the two adipokines in each group. Methods 3T3-L1 adipocytes were incubated with triiodothyronine at physiological dose (10nM) and supraphysiological doses (100nM or 1,000nM), or without triiodothyronine (control, C) for 0.5, 6, or 24 hours. Leptin and adiponectin mRNA was detected using real-time polymerase chain reaction (RT-PCR). One-way analyses of variance, Tukey’s test or Student’s t test, were used to analyze data, and significance level was set at 5%. Results Leptin levels decreased in the 1,000nM-dose group after 0.5 hour. Adiponectin levels dropped in the 10nM-dose group, but increased at the 100nM dose. After 6 hours, both genes were suppressed in all hormone concentrations. After 24 hours, leptin levels increased at 10, 100 and 1,000nM groups as compared to the control group; and adiponectin levels increased only in the 100nM group as compared to the control group. Conclusion These results demonstrated fast actions of triiodothyronine on the leptin and adiponectin expression, starting at 0.5 hour, at a dose of 1,000nM for leptin and 100nM for adiponectin. Triiodothyronine stimulated or inhibited the expression of adipokines in adipocytes at different times and doses which may be useful to assist in the treatment of obesity, assuming that leptin is increased and adiponectin is decreased, in obesity cases. PMID:25993072

Triiodothyronine modulates the expression of leptin and adiponectin in 3T3-L1 adipocytes.

PubMed

Oliveira, Miriane de; de Síbio, Maria Teresa; Olimpio, Regiane Marques Castro; Moretto, Fernanda Cristina Fontes; Luvizotto, Renata de Azevedo Melo; Nogueira, Celia Regina

2015-01-01

To study the effect of different doses of triiodothyronine on gene expression of the adipokines leptin and adiponectin, at different times, and to evaluate the difference in expression between the two adipokines in each group. 3T3-L1 adipocytes were incubated with triiodothyronine at physiological dose (10nM) and supraphysiological doses (100nM or 1,000nM), or without triiodothyronine (control, C) for 0.5, 6, or 24 hours. Leptin and adiponectin mRNA was detected using real-time polymerase chain reaction (RT-PCR). One-way analyses of variance, Tukey's test or Student's t test, were used to analyze data, and significance level was set at 5%. Leptin levels decreased in the 1,000nM-dose group after 0.5 hour. Adiponectin levels dropped in the 10nM-dose group, but increased at the 100nM dose. After 6 hours, both genes were suppressed in all hormone concentrations. After 24 hours, leptin levels increased at 10, 100 and 1,000nM groups as compared to the control group; and adiponectin levels increased only in the 100nM group as compared to the control group. These results demonstrated fast actions of triiodothyronine on the leptin and adiponectin expression, starting at 0.5 hour, at a dose of 1,000nM for leptin and 100nM for adiponectin. Triiodothyronine stimulated or inhibited the expression of adipokines in adipocytes at different times and doses which may be useful to assist in the treatment of obesity, assuming that leptin is increased and adiponectin is decreased, in obesity cases.

Lemna minor plants chronically exposed to ionising radiation: RNA-seq analysis indicates a dose rate dependent shift from acclimation to survival strategies.

PubMed

Van Hoeck, Arne; Horemans, Nele; Nauts, Robin; Van Hees, May; Vandenhove, Hildegarde; Blust, Ronny

2017-04-01

Ecotoxicological research provides knowledge on ionising radiation-induced responses in different plant species. However, the sparse data currently available are mainly extracted from acute exposure treatments. To provide a better understanding of environmental exposure scenarios, the response to stress in plants must be followed in more natural relevant chronic conditions. We previously showed morphological and biochemical responses in Lemna minor plants continuously exposed for 7days in a dose-rate dependent manner. In this study responses on molecular (gene expression) and physiological (photosynthetic) level are evaluated in L. minor plants exposed to ionising radiation. To enable this, we examined the gene expression profiles of irradiated L. minor plants by using an RNA-seq approach. The gene expression data reveal indications that L. minor plants exposed at lower dose rates, can tolerate the exposure by triggering acclimation responses. In contrast, at the highest dose rate tested, a high number of genes related to antioxidative defense systems, DNA repair and cell cycle were differentially expressed suggesting that only high dose rates of ionising radiation drive L. minor plants into survival strategies. Notably, the photosynthetic process seems to be unaffected in L. minor plants among the tested dose rates. This study, supported by our earlier work, clearly indicates that plants shift from acclimation responses towards survival responses at increasing dose rates of ionising radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

Toxic Diatom Aldehydes Affect Defence Gene Networks in Sea Urchins

PubMed Central

Varrella, Stefano; Ruocco, Nadia; Ianora, Adrianna; Bentley, Matt G.; Costantini, Maria

2016-01-01

Marine organisms possess a series of cellular strategies to counteract the negative effects of toxic compounds, including the massive reorganization of gene expression networks. Here we report the modulated dose-dependent response of activated genes by diatom polyunsaturated aldehydes (PUAs) in the sea urchin Paracentrotus lividus. PUAs are secondary metabolites deriving from the oxidation of fatty acids, inducing deleterious effects on the reproduction and development of planktonic and benthic organisms that feed on these unicellular algae and with anti-cancer activity. Our previous results showed that PUAs target several genes, implicated in different functional processes in this sea urchin. Using interactomic Ingenuity Pathway Analysis we now show that the genes targeted by PUAs are correlated with four HUB genes, NF-κB, p53, δ-2-catenin and HIF1A, which have not been previously reported for P. lividus. We propose a working model describing hypothetical pathways potentially involved in toxic aldehyde stress response in sea urchins. This represents the first report on gene networks affected by PUAs, opening new perspectives in understanding the cellular mechanisms underlying the response of benthic organisms to diatom exposure. PMID:26914213

Comprehensive DNA methylation analysis of human neuroblastoma cells treated with blonanserin.

PubMed

Murata, Yui; Nishioka, Masaki; Bundo, Miki; Sunaga, Fumiko; Kasai, Kiyoto; Iwamoto, Kazuya

2014-03-20

Blonanserin is a second-generation antipsychotic drug for schizophrenia. The pharmacological actions of blonanserin are shown to be the antagonism of dopamine receptor 2 and serotonin receptors. However, its molecular mechanisms in brain cells have not been fully characterized. Accumulating evidence suggests that antipsychotic drugs and mood stabilizers show epigenetic effects on a wide range of genes in animal and cellular models. We performed genome-wide DNA methylation analysis targeting 479,814 CpG sites of cultured human neuroblastoma cells administered with blonanserin. We found that 3,057 CpG sites showed statistically significant changes in DNA methylation at two different doses of blonanserin (1.36 nM and 13.6 nM). These included hypermethylated CpG sites that were enriched in genes related to axonogenesis and cell morphogenesis involved in neuron differentiation. We also showed that the global effect on DNA methylome depends on the concentration of the drug. With a high dose of blonanserin, the overall methylation levels across all CpG sites significantly increased. These increases in DNA methylation were prominent in the CpG sites distant from promoter regions. We further examined DNA methylation changes in specific genes implicated for the actions of antipsychotic drugs, such as the dopamine receptor 2 (DRD2) gene and the serotonin receptor 2A (HTR2A) gene. We observed that CpG sites that were located within DRD2 and HTR2A genes were significantly hypermethylated by blonanserin. The DNA methylation changes induced by the treatment with blonanserin will be useful for understanding its pharmacological actions at the cellular level. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Dietary cholecalciferol regulates the recruitment and growth of skeletal muscle fibers and the expressions of myogenic regulatory factors and the myosin heavy chain in European sea bass larvae.

PubMed

Alami-Durante, Hélène; Cluzeaud, Marianne; Bazin, Didier; Mazurais, David; Zambonino-Infante, José L

2011-12-01

The aim of this study was to determine whether dietary cholecalciferol affects the recruitment and growth of axial skeletal muscle fibers in first-feeding European sea bass. Larvae were fed diets containing 0.28 (VD-L, low dose), 0.69 (VD-C, control dose), or 3.00 (VD-H, high dose) mg cholecalciferol/kg from 9 to 44 d posthatching (dph). Larvae were sampled at 44 dph for quantification of somatic growth, muscle growth, and muscle growth dynamics and at 22 and 44 dph for the relative quantification of transcripts encoded by genes involved in myogenesis, cell proliferation, and muscle structure. The weight increase of the VD-L-fed larvae was less than that of the VD-H-fed group, whereas that of VD-C-fed larvae was intermediate. The level of expression of genes involved in cell proliferation (PCNA) and early myogenesis (Myf5) decreased between 22 and 44 dph, whereas that of the myogenic determination factor MyoD1 and that of genes involved in muscle structure and function (myosin heavy chain, myosin light chains 2 and 3) increased. Dietary cholecalciferol regulated Myf5, MyoD1, myogenin, and myosin heavy chain gene expression, with a gene-specific shape of response. The maximum hypertrophy of white muscle fibers was higher in larvae fed the VD-C and VD-H diets than in larvae fed the VD-L diet. White muscle hyperplasia was highly stimulated in VD-H-fed larvae compared to VD-L- and VD-C-fed ones. These findings demonstrate a dietary cholecalciferol effect on skeletal muscle growth mechanisms of a Teleost species.

Hepatitis B virus x gene and cyanobacterial toxins promote aflatoxin B1-induced hepatotumorigenesis in mice

PubMed Central

Lian, Min; Liu, Ying; Yu, Shun-Zhang; Qian, Geng-Sun; Wan, Shu-Guang; Dixon, Kenneth R

2006-01-01

AIM: To assess the combinative role of aflatoxin B1 (AFB1), cyanobacterial toxins (cyanotoxins), and hepatitis B virus (HBV) x gene in hepatotumorigenicity. METHODS: One-week-old animals carrying HBV x gene and their wild-type littermates were intraperitoneally (ip) injected with either single-dose AFB1 [6 mg/kg body weight (bw)], repeated-dose cyanotoxins (microcystin-LR or nodularin, 10 μg/kg bw once a week for 15 wk), DMSO (vehicle control) alone, or AFB1 followed by cyanotoxins a week later, and were sacrificed at 24 and 52 wk post-treatment. RESULTS: AFB1 induced liver tumors in 13 of 29 (44.8%) transgenic mice at 52 wk post-treatment, significantly more frequent than in wild-type mice (13.3%). This significant difference was not shown in the 24-wk study. Compared with AFB1 exposure alone, MC-LR and nodularin yielded approximately 3-fold and 6-fold increases in the incidence of AFB1-induced liver tumors in wild-type animals at 24 wk, respectively. HBV x gene did not further elevate the risk associated with co-exposure to AFB1 and cyanotoxins. With the exception of an MC-LR-dosed wild-type mouse, no liver tumor was observed in mice treated with cyanotoxins alone at 24 wk. Neither DMSO-treated transgenic mice nor their wild-type littermates had pathologic alterations relevant to hepatotumorigenesis in even up to 52 wk. CONCLUSION: HBV x gene and nodularin promote the development of AFB1-induced liver tumors. Co-exposure to AFB1 and MC-LR tends to elevate the risk of liver tumors at 24 wk relative to exposure to one of them. The combinative effect of AFB1, cyanotoxins and HBVx on hepatotumorigenesis is weak at 24 wk. PMID:16718789

Long-term correction of canine hemophilia B by gene transfer of blood coagulation factor IX mediated by adeno-associated viral vector.

PubMed

Herzog, R W; Yang, E Y; Couto, L B; Hagstrom, J N; Elwell, D; Fields, P A; Burton, M; Bellinger, D A; Read, M S; Brinkhous, K M; Podsakoff, G M; Nichols, T C; Kurtzman, G J; High, K A

1999-01-01

Hemophilia B is a severe X-linked bleeding diathesis caused by the absence of functional blood coagulation factor IX, and is an excellent candidate for treatment of a genetic disease by gene therapy. Using an adeno-associated viral vector, we demonstrate sustained expression (>17 months) of factor IX in a large-animal model at levels that would have a therapeutic effect in humans (up to 70 ng/ml, adequate to achieve phenotypic correction, in an animal injected with 8.5x10(12) vector particles/kg). The five hemophilia B dogs treated showed stable, vector dose-dependent partial correction of the whole blood clotting time and, at higher doses, of the activated partial thromboplastin time. In contrast to other viral gene delivery systems, this minimally invasive procedure, consisting of a series of percutaneous intramuscular injections at a single timepoint, was not associated with local or systemic toxicity. Efficient gene transfer to muscle was shown by immunofluorescence staining and DNA analysis of biopsied tissue. Immune responses against factor IX were either absent or transient. These data provide strong support for the feasibility of the approach for therapy of human subjects.

Effects of Coriolus versicolor polysaccharide B on monocyte chemoattractant protein 1 gene expression in rat.

PubMed

Song, Lie-Chang; Chen, Hai-Sheng; Lou, Ning; Song, Chang; Zeng, Jun; Fu, Ting-Huan

2002-06-01

To investigate the effect of Coriolus versicolor polysaccharide B (CVPS-B), a new water-soluble component of polysaccharides from the fungus Coriolus versicolor (Fr) L on monocyte chemoattractant protein-1 (MCP-1) gene expression in rat splenocytes. Expression of MCP-1 mRNA in rat splenocytes was examined by reverse transcription-polymerase chain reaction (RT-PCR) with beta- actin as an internal standard. Sequencing of RT-PCR products was performed to confirm their specificity in MCP-1 gene composition. (1) Without pre-treatment of lipopolysaccharide (LPS), the relative MCP-1 mRNA expression ratios (MCP-1/beta-actin) for the saline control group and for CVPS-B groups in 3 different doses (10, 20, and 30 mg . kg-1 . d-1, ip, for 4 d) were 1.4 +/- 0.3, 1.6 +/- 0.4, 1.7 +/- 0.5, and 1.5 +/- 0.4, respectively (P > 0.05); (2) LPS (10 microg . kg-1, ip) enhanced the expression of MPC-1 mRNA by the ratio of 114 %; (3) pre-treatment with CVPS-B of 4 different doses (5, 10, 30, and 50 mg . kg-1 . d-1, ip, for 4 d) decreased the LPS induced expression of MPC-1 mRNA by the ratios of 51 %, 70 %, 84 %, and 99 %, respectively (n = 6). In a dose-related fashion, CVPS-B inhibited the expression of MCP-1 mRNA induced by LPS in the rat splenocytes, but did not significantly affect the expression of MPC-1 mRNA in the normal rat.

Indirubin, a component of Ban-Lan-Gen, activates CYP3A4 gene transcription through the human pregnane X receptor.

PubMed

Kumagai, Takeshi; Aratsu, Yusuke; Sugawara, Ryosuke; Sasaki, Takamitsu; Miyairi, Shinichi; Nagata, Kiyoshi

2016-04-01

Ban-Lan-Gen is the common name for the dried roots of indigo plants, including Polygonum tinctorium, Isatis indigotica, Isatis tinctoria, and Strobilanthes cusia. Ban-Lan-Gen is frequently used as an anti-inflammatory and an anti-viral for the treatment of hepatitis, influenza, and various types of inflammation. One of the cytochrome P450 (CYP) enzymes, CYP3A4, is responsible for the metabolism of a wide variety of xenobiotics, including an estimated 60% of all clinically used drugs. In this study, we investigated the effect of Ban-Lan-Gen on the transcriptional activation of the CYP3A4 gene. Ban-Lan-Gen extract increased CYP3A4 gene reporter activity in a dose-dependent manner. Indirubin, one of the biologically active ingredients in the Ban-Lan-Gen, also dose-dependently increased CYP3A4 gene reporter activity. Expression of short hairpin RNA for the human pregnane X receptor (hPXR-shRNA) inhibited CYP3A4 gene reporter activity, and overexpression of human PXR increased indirubin- and rifampicin-induced CYP3A4 gene reporter activity. Furthermore, indirubin induced CYP3A4 mRNA expression in HepG2 cells. Taken together, these results indicate that indirubin, a component of Ban-Lan-Gen, activated CYP3A4 gene transcription through the activation of the human PXR. Copyright © 2016. Published by Elsevier Ltd.

Monitoring exposure to atomic bomb radiation by somatic mutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akiyama, Mitoshi; Kyoizumi, Seishi; Kusunoki, Yoichiro

Atomic bomb survivors are a population suitable for studying the relationship between somatic mutation and cancer risk because their exposure doses are relatively well known and their dose responses in terms of cancer risk have also been thoroughly studied. An analysis has been made of erythrocyte glycophorin A (GPA) gene mutations in 1,226 atomic bomb survivors in Hiroshima and Nagasaki. The GPA mutation frequency (Mf) increased slightly but significantly with age at the time of measurement and with the number of cigarettes smoked. After adjustment for the effect of smoking, the Mf was significantly higher in males than in femalesmore » and higher in Hiroshima than in Nagasaki. All of these characteristics of the background GPA Mf were in accord with those of solid tumor incidence obtained from an earlier epidemiological study of A-bomb survivors. Analysis of the dose effect on Mf revealed the doubling dose to be about 1.20 Sv and the minimum dose for detection of a significant increase to be about 0.24 Sv. No significant dose effect for difference in sex, city, or age at the time of bombing was observed. Interestingly, the doubling dose for the GPA Mf approximated that for solid cancer incidence (1.59 Sv). And the minimum dose for detection was not inconsistent with the data for solid cancer incidence. The dose effect was significantly higher in those diagnosed with cancer before or after measurement than in those without a history of cancer. These findings are consistent with the hypothesis that somatic mutations are the main cause of excess cancer risk from radiation exposure. 27 refs., 2 figs.« less

Oxidative stress induces senescence in human mesenchymal stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brandl, Anita; Meyer, Matthias; Bechmann, Volker

Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated {beta}-galactosidase positivity. Prolongedmore » low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.« less

THYROID INSUFFICIENCY AND GENE EXPRESSION IN DEVELOPING RAT BRAIN: A DOSE RESPONSE STUDY.

EPA Science Inventory

Thyroid Insufficiency and Gene Expression in Developing Rat Brain: A Dose Response Study. JE Royland and ME Gilbert, Neurotox. Div., U.S. EPA, RTP, NC, USA. Endocrine disruption is an area of major concern in environmental neurotoxicity. Deficits in thyroid hormone (TH) levels h...

Integrated molecular analysis indicates undetectable change in DNA damage in mice after continuous irradiation at ~ 400-fold natural background radiation.

PubMed

Olipitz, Werner; Wiktor-Brown, Dominika; Shuga, Joe; Pang, Bo; McFaline, Jose; Lonkar, Pallavi; Thomas, Aline; Mutamba, James T; Greenberger, Joel S; Samson, Leona D; Dedon, Peter C; Yanch, Jacquelyn C; Engelward, Bevin P

2012-08-01

In the event of a nuclear accident, people are exposed to elevated levels of continuous low dose-rate radiation. Nevertheless, most of the literature describes the biological effects of acute radiation. DNA damage and mutations are well established for their carcinogenic effects. We assessed several key markers of DNA damage and DNA damage responses in mice exposed to low dose-rate radiation to reveal potential genotoxic effects associated with low dose-rate radiation. We studied low dose-rate radiation using a variable low dose-rate irradiator consisting of flood phantoms filled with 125Iodine-containing buffer. Mice were exposed to 0.0002 cGy/min (~ 400-fold background radiation) continuously over 5 weeks. We assessed base lesions, micronuclei, homologous recombination (HR; using fluorescent yellow direct repeat mice), and transcript levels for several radiation-sensitive genes. We did not observe any changes in the levels of the DNA nucleobase damage products hypoxanthine, 8-oxo-7,8-dihydroguanine, 1,N6-ethenoadenine, or 3,N4-ethenocytosine above background levels under low dose-rate conditions. The micronucleus assay revealed no evidence that low dose-rate radiation induced DNA fragmentation, and there was no evidence of double strand break-induced HR. Furthermore, low dose-rate radiation did not induce Cdkn1a, Gadd45a, Mdm2, Atm, or Dbd2. Importantly, the same total dose, when delivered acutely, induced micronuclei and transcriptional responses. These results demonstrate in an in vivo animal model that lowering the dose-rate suppresses the potentially deleterious impact of radiation and calls attention to the need for a deeper understanding of the biological impact of low dose-rate radiation.

DNA damage and transcriptional changes induced by tributyltin (TBT) after short in vivo exposures of Chironomus riparius (Diptera) larvae.

PubMed

Morales, Mónica; Martínez-Paz, Pedro; Ozáez, Irene; Martínez-Guitarte, José Luis; Morcillo, Gloria

2013-08-01

Tributyltin (TBT) is a widespread environmental contaminant in aquatic systems whose adverse effects in development and reproduction are related to its well-known endocrine-disrupting activity. In this work, the early molecular effects of TBT in Chironomus riparius (Diptera) were evaluated by analyzing its DNA damaging potential and the transcriptional response of different endocrine-related genes. Twenty-four-hour in vivo exposures of the aquatic larvae, at environmentally relevant doses of TBT, revealed genotoxic activity as shown by significant increases in DNA strand breaks quantified with the comet assay. TBT was also able to induce significant increases in transcripts from the ecdysone receptor gene (EcR), the ultraspiracle gene (usp) (insect ortholog of the retinoid X receptor), the estrogen-related receptor (ERR) gene and the E74 early ecdysone-inducible gene, as measured by real-time RT-PCR. In contrast, the expression of the vitellogenin (vg) gene remained unaltered, while the hsp70 gene appeared to be down-regulated. The ability of TBT to up-regulate hormonal target genes provides the first evidence, at genomic level, of its endocrine disruptive effects and also suggests a mechanism of action that mimics ecdysteroid hormones in insects. These data reveal for the first time the early genomic effects of TBT on an insect genome. Copyright © 2013 Elsevier Inc. All rights reserved.

Dyskeratosis congenita--two siblings with a new missense mutation in the DKC1 gene.

PubMed

Coelho, Joana Dias; Lestre, Sara; Kay, Teresa; Lopes, Maria João Paiva; Fiadeiro, Teresa; Apetato, Margarida

2011-01-01

Dyskeratosis congenital is reported in two siblings. They presented with the classic triad of mucocutaneous features: leukoplakia of the tongue, dystrophic nails, and a widespread reticulate pigmentation on the neck and upper chest. A genetic analysis was performed and a new missense mutation S356P, hemizygous, was identified in the DKC1 gene in both patients. Acitretin was started at a low-dose in both patients, resulting in clinical improvement and important, positive psychosocial effects. © 2011 Wiley Periodicals, Inc.

Epigallocatechin activates haem oxygenase-1 expression via protein kinase Cδ and Nrf2

PubMed Central

Ogborne, Richard M.; Rushworth, Stuart A.; O’Connell, Maria A.

2008-01-01

The Nrf2/anti-oxidant response element (ARE) pathway plays an important role in regulating cellular anti-oxidants, including haem oxygenase-1 (HO-1). Various kinases have been implicated in the pathways leading to Nrf2 activation. Here, we investigated the effect of epigallocatechin (EGC) on ARE-mediated gene expression in human monocytic cells. EGC time and dose dependently increased HO-1 mRNA and protein expression but had minimal effect on expression of other ARE-regulated genes, including NAD(P)H:quinone oxidoreductase 1, glutathione cysteine ligase and ferritin. siRNA knock down of Nrf2 significantly inhibited EGC-induced HO-1 expression. Furthermore, inhibition of PKC by Ro-31-8220 dose dependently decreased EGC-induced HO-1 mRNA expression, whereas MAP kinase and phosphatidylinositol-3-kinase pathway inhibitors had no significant effect. EGC stimulated phosphorylation of PKCαβ and δ in THP-1 cells. PKCδ inhibition significantly decreased EGC-induced HO-1 mRNA expression, whereas PKCα- and β-specific inhibitors had no significant effect. These results demonstrate for the first time that EGC-induced HO-1 expression occurs via PKCδ and Nrf2. PMID:18586007

Dose-Response Curves of the FDXR and RAD51 Genes with 6 and 18 MV Beam Energies in Human Peripheral Blood Lymphocytes.

PubMed

Saberi, Alihossein; Khodamoradi, Ehsan; Tahmasebi Birgani, Mohammad Javad; Makvandi, Manoochehr; Noori, Bijan

2016-11-01

Rapid dose assessment using biological dosimetry methods is essential to increase the chance of survival of exposed individuals in radiation accidents. We compared the expression levels of the FDXR and RAD51 genes at 6 and 18 MV beam energies in human peripheral blood lymphocytes. The results of our study can be used to analyze radiation energy in biological dosimetry. For this in vitro experimental study, from 36 students in the medical physics and virology departments, seven voluntary, healthy, non-smoking male blood donors of Khuzestan ethnicity with no history of exposure to ionization radiation were selected using simple randomized sampling. Sixty-three peripheral blood samples were collected from the seven healthy donors. Human peripheral blood was then exposed to doses of 0, 0.2, 0.5, 2, and 4 Gy with 6 and 18 MV beam energies in a Linac Varian 2100C/D (Varian, USA) at Golestan hospital in Ahvaz, Iran. After RNA extraction and cDNA synthesis, the expression levels of FDXR and RAD51 were determined 24 hours post-irradiation using the gel-purified reverse transcription polymerase chain reaction (RT-PCR) technique and TaqMan strategy (by real-time PCR). The expression level of FDXR gene was significantly increased at doses of 2 Gy and 4 Gy in the 6 - 18 MV energy range (P < 0.001 and P < 0.008, respectively). The medians with interquartile ranges (IQRs) of the copy numbers of the FDXR gene at 2 Gy and 4 Gy doses under 6 and 18 MV beam energies were 2393.59 (1798.21, 2575.37) and 2983.00 (2199.48, 3643.82) and 3779.12 (3051.40, 5120.74) and 5051.26 (4704.83, 5859.17), respectively. However, RAD51 gene expression levels only showed a significant difference between samples at a dose of 2 Gy with 6 and 18 MV beam energies, respectively (P < 0.040). The medians with IQRs of the copy numbers of the RAD51 gene were 2092.77 (1535.78, 2705.61) and 3412.57 (2979.72, 4530.61) at beam energies of 6 and 18 MV, respectively. The data suggest that the expression analysis of the FDXR gene, contrary to that of the RAD51 gene, may be suitable for assessment of high-energy X-ray. In addition, RAD51 is not a suitable gene for dose assessment in biological dosimetry.

Study on DNA Damage Induced by Neon Beam Irradiation in Saccharomyces Cerevisiae

NASA Astrophysics Data System (ADS)

Lu, Dong; Li, Wenjian; Wu, Xin; Wang, Jufang; Ma, Shuang; Liu, Qingfang; He, Jinyu; Jing, Xigang; Ding, Nan; Dai, Zhongying; Zhou, Jianping

2010-12-01

Yeast strain Saccharomyces cerevisiae was irradiated with different doses of 85 MeV/u 20Ne10+ to investigate DNA damage induced by heavy ion beam in eukaryotic microorganism. The survival rate, DNA double strand breaks (DSBs) and DNA polymorphic were tested after irradiation. The results showed that there were substantial differences in DNA between the control and irradiated samples. At the dose of 40 Gy, the yeast cell survival rate approached 50%, DNA double-strand breaks were barely detectable, and significant DNA polymorphism was observed. The alcohol dehydrogenase II gene was amplified and sequenced. It was observed that base changes in the mutant were mainly transversions of T→G and T→C. It can be concluded that heavy ion beam irradiation can lead to change in single gene and may be an effective way to induce mutation.

Dose-sensitivity, conserved non-coding sequences, and duplicate gene retention through multiple tetraploidies in the grasses.

PubMed

Schnable, James C; Pedersen, Brent S; Subramaniam, Sabarinath; Freeling, Michael

2011-01-01

Whole genome duplications, or tetraploidies, are an important source of increased gene content. Following whole genome duplication, duplicate copies of many genes are lost from the genome. This loss of genes is biased both in the classes of genes deleted and the subgenome from which they are lost. Many or all classes are genes preferentially retained as duplicate copies are engaged in dose sensitive protein-protein interactions, such that deletion of any one duplicate upsets the status quo of subunit concentrations, and presumably lowers fitness as a result. Transcription factors are also preferentially retained following every whole genome duplications studied. This has been explained as a consequence of protein-protein interactions, just as for other highly retained classes of genes. We show that the quantity of conserved noncoding sequences (CNSs) associated with genes predicts the likelihood of their retention as duplicate pairs following whole genome duplication. As many CNSs likely represent binding sites for transcriptional regulators, we propose that the likelihood of gene retention following tetraploidy may also be influenced by dose-sensitive protein-DNA interactions between the regulatory regions of CNS-rich genes - nicknamed bigfoot genes - and the proteins that bind to them. Using grass genomes, we show that differential loss of CNSs from one member of a pair following the pre-grass tetraploidy reduces its chance of retention in the subsequent maize lineage tetraploidy.

Effects of de-alcoholised wines with different polyphenol content on DNA oxidative damage, gene expression of peripheral lymphocytes, and haemorheology: an intervention study in post-menopausal women.

PubMed

Giovannelli, Lisa; Pitozzi, Vanessa; Luceri, Cristina; Giannini, Lucia; Toti, Simona; Salvini, Simonetta; Sera, Francesco; Souquet, Jean-Marc; Cheynier, Veronique; Sofi, Francesco; Mannini, Lucia; Gori, Anna Maria; Abbate, Rosanna; Palli, Domenico; Dolara, Piero

2011-02-01

Epidemiological studies suggest that a moderate consumption of wine is associated with a reduced risk of cardiovascular diseases and with a reduced mortality for all causes, possibly due to increased antioxidant defences. The present intervention study was undertaken to evaluate the in vivo effects of wine polyphenols on gene expression in humans, along with their supposed antioxidant activity. Blood haemorheology and platelet function were also evaluated. In order to avoid interferences from alcohol, we used de-alcoholised wine (DAW) with different polyphenol content. A randomised cross-over trial of high-proanthocyanidin (PA) red DAW (500 mL/die, PA dose = 7 mg/kg b.w.) vs. low-PA rosé DAW (500 mL/die, PA dose = 0.45 mg/kg) was conducted in 21 post-menopausal women in Florence, Italy. Oxidative DNA damage by the comet assay and gene expression by microarray was measured in peripheral blood lymphocytes, collected during the study period. Blood samples were also collected for the evaluation of haematological, haemostatic, haemorheological, and inflammatory parameters. The results of the present study provide evidence that consumption of substantial amounts of de-alcoholised wine for 1 month does not exert a protective activity towards oxidative DNA damage, nor modifies significantly the gene expression profile of peripheral lymphocytes, whereas it shows blood-fluidifying actions, expressed as a significant decrease in blood viscosity. However, this effect does not correlate with the dosage of polyphenols of the de-alcoholised wine. More intervention studies are needed to provide further evidence of the health-protective effects of wine proanthocyanidins.

UVB Induces a Genome-Wide Acting Negative Regulatory Mechanism That Operates at the Level of Transcription Initiation in Human Cells

PubMed Central

Gyenis, Ákos; Umlauf, David; Újfaludi, Zsuzsanna; Boros, Imre; Ye, Tao; Tora, Làszlò

2014-01-01

Faithful transcription of DNA is constantly threatened by different endogenous and environmental genotoxic effects. Transcription coupled repair (TCR) has been described to stop transcription and quickly remove DNA lesions from the transcribed strand of active genes, permitting rapid resumption of blocked transcription. This repair mechanism has been well characterized in the past using individual target genes. Moreover, numerous efforts investigated the fate of blocked RNA polymerase II (Pol II) during DNA repair mechanisms and suggested that stopped Pol II complexes can either backtrack, be removed and degraded or bypass the lesions to allow TCR. We investigated the effect of a non-lethal dose of UVB on global DNA-bound Pol II distribution in human cells. We found that the used UVB dose did not induce Pol II degradation however surprisingly at about 93% of the promoters of all expressed genes Pol II occupancy was seriously reduced 2–4 hours following UVB irradiation. The presence of Pol II at these cleared promoters was restored 5–6 hours after irradiation, indicating that the negative regulation is very dynamic. We also identified a small set of genes (including several p53 regulated genes), where the UVB-induced Pol II clearing did not operate. Interestingly, at promoters, where Pol II promoter clearance occurs, TFIIH, but not TBP, follows the behavior of Pol II, suggesting that at these genes upon UVB treatment TFIIH is sequestered for DNA repair by the TCR machinery. In agreement, in cells where the TCR factor, the Cockayne Syndrome B protein, was depleted UVB did not induce Pol II and TFIIH clearance at promoters. Thus, our study reveals a UVB induced negative regulatory mechanism that targets Pol II transcription initiation on the large majority of transcribed gene promoters, and a small subset of genes, where Pol II escapes this negative regulation. PMID:25058334

Lactic Acid Bacteria Improves Peyer's Patch Cell-Mediated Immunoglobulin A and Tight-Junction Expression in a Destructed Gut Microbial Environment.

PubMed

Kim, Sung Hwan; Jeung, Woonhee; Choi, Il-Dong; Jeong, Ji-Woong; Lee, Dong Eun; Huh, Chul-Sung; Kim, Geun-Bae; Hong, Seong Soo; Shim, Jae-Jung; Lee, Jung Lyoul; Sim, Jae-Hun; Ahn, Young-Tae

2016-06-28

To evaluate the effects of lactic acid bacteria (LAB) on Peyer's patch cells, mice were treated with a high dose of kanamycin to disturb the gut microbial environment. The overarching goal was to explore the potential of LAB for use as a dietary probiotic that buffers the negative consequences of antibiotic treatment. In vitro, LAB stimulated the production of immunoglobulin A (IgA) from isolated Peyer's patch cells. Inflammation-related genes (TNF-α, IL-1β, and IL-8) were up-regulated in Caco-2 cells stimulated with lipopolysaccharide (LPS), while tight-junction-related genes (ZO-1 and occludin) were down-regulated; the effects of LPS on inflammatory gene and tight-junction gene expression were reversed by treatment with LAB. Mice treated with a high dose of kanamycin showed increased serum IgE levels and decreases in serum IgA and fecal IgA levels; the number of Peyer's patch cells decreased with kanamycin treatment. However, subsequent LAB treatment was effective in reducing the serum IgE level and recovering the serum IgA and fecal IgA levels, as well as the number of Peyer's patch cells. In addition, ZO-1 and occludin mRNA levels were up-regulated in the ileum tissues of mice receiving LAB treatment. Lactic acid bacteria can enhance the intestinal immune system by improving the integrity of the intestinal barrier and increasing the production of IgA in Peyer's patches. Lactic acid bacteria should be considered a potential probiotic candidate for improving intestinal immunity, particularly in mitigating the negative consequences of antibiotic use.

Nanospecific Inhibition of Pyoverdine Siderophore Production in Pseudomonas Chlororaphis O6 by CuO Nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dimkpa, Christian O.; McLean, Joan E.; Britt, David W.

2012-03-01

As traditional antibiotics become less effective against a growing number of pathogens, engineered nanoparticles (NPs) are becoming more widely applied as biocides. NPs of Ag, ZnO, and CuO exhibit dose-dependent antimicrobial activity; however, information is scant on the impact of sublethal levels of NPs on bacteria. In this paper, we evaluated the effect of a sublethal concentration (200 mg/L) of commercial CuO NPs on the expression of genes involved in the production of the fluorescent siderophore, pyoverdine (PVD) in the plant-beneficial bacterium Pseudomonas chlororaphis O6. PVDs are important in microbe-microbe and microbe-plant interactions, and are a virulence factor in pathogenicmore » pseudomonads. Cells challenged with the NPs had reduced amounts of PVD in their periplasm and the external medium. The NPs impaired the expression of genes involved in transport of the PVD precursor through the plasmamembrane, PVD maturation in the periplasm, and export through the outer membrane. Also, expression from one of three predicted Fe-PVD receptors was reduced by the NPs. As these effects were not observed for cells challenged with copper ions, this is a nanoparticlespecific phenomenon mediating cellular reprogramming in bacteria, affecting secondary metabolism and thus associated critical microbial processes. The regulation of bacterial genes and secondary metabolites by sublethal doses of a common metal oxide NP has strong environmental and medical implications.« less

Transcriptional up-regulation of the human androgen receptor by androgen in bone cells.

PubMed

Wiren, K M; Zhang, X; Chang, C; Keenan, E; Orwoll, E S

1997-06-01

Androgen regulation of androgen receptor (AR) expression has been observed in a variety of tissues, generally as inhibition, and is thought to attenuate cellular responses to androgen. AR is expressed in osteoblasts, the bone-forming cell, suggesting direct actions of androgens on bone. Here we characterized the effect of androgen exposure on AR gene expression in human osteoblastic SaOS-2 and U-2 OS cells. Treatment of osteoblastic cells with the nonaromatizable androgen 5alpha-dihydrotestosterone increased AR steady state messenger RNA levels in a time- and dose-dependent fashion. Reporter assays with 2.3 kilobases of the proximal 5'-flanking region of the human AR promoter linked to the chloramphenicol acetyltransferase gene in transfected cultures showed that up-regulation of AR promoter activity by androgen was time and dose dependent. Treatment with other steroid hormones, including progesterone, 17beta-estradiol, and dexamethasone, was without effect. The antiandrogen hydroxyflutamide completely antagonized androgen up-regulation. Thus, in contrast to many other androgen target tissues, androgen exposure increases steady state AR messenger RNA levels in osteoblasts. This regulation occurs at least partially at the level of transcription, is mediated by the 5'-promoter region of the AR gene, and is dependent on functional AR. These results suggest that physiological concentrations of androgens have significant effects on AR expression in skeletal tissue.

Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells.

PubMed

Elmetwally, Mohammed A; Halawa, Amal A; Lenis, Yasser Y; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W

2018-04-07

This study evaluated the effects of bisphenol A (BPA) on proliferation of ovine trophectoderm (oTr1) cells, as well as expression of genes for transport of arginine and synthesis of polyamines. BPA reduced proliferation of oTr1 cells at concentrations of 1 × 10 -6 , 1 × 10 -5 , 1 × 10 -4  M compared to concentrations of 0, 1 × 10 -9 , and 1 × 10 -8  M at 24 and 96 h of culture. Lower concentrations of BPA significantly increased expression of mRNAs for agmatinase (AGMAT), arginine decarboxylase (ADC), ornithine decarboxylase (ODC1) and solute carrier family 7 member 1 (SLC7A1). Similarly, synthesis of polyamines by oTr1 cells was greatest at lower concentrations of BPA and decreased as the dose of BPA increased. Expression of mRNAs for interferon tau (IFNT) and insulin-like growth factor 2 (IGF2) by oTr1 cells was greater than for controls at 1 × 10 -9  M BPA. Overall, the effects of BPA on proliferation and gene expression by oTr1 cells were highly dose-dependent. Copyright © 2018 Elsevier Inc. All rights reserved.

Intravaginal gene silencing using biodegradable polymer nanoparticles densely loaded with small-interfering RNA

PubMed Central

Woodrow, Kim A.; Cu, Yen; Booth, Carmen J.; Saucier-Sawyer, Jennifer K.; Wood, Monica J.; Saltzman, W. Mark

2009-01-01

Vaginal instillation of small-interfering RNA (siRNA) using liposomes has led to silencing of endogenous genes in the genital tract and protected against challenge from infectious disease. Although siRNA lipoplexes are easily formulated, several of the most effective transfection agents available commercially may be toxic to the mucosal epithelia and none are able to provide controlled or sustained release. Here, we demonstrate an alternate approach, using nanoparticles composed entirely of FDA-approved materials. To render these materials effective for gene silencing we developed novel approaches to load them with high amounts of siRNA. A single dose of siRNA-loaded nanoparticles to the mouse female reproductive tract caused efficient and sustained gene silencing. Knockdown of gene expression was observed proximal (in the vaginal lumen) and distal (in the uterine horns) to the site of topical delivery. In addition, nanoparticles penetrated deep into the epithelial tissue. This is the first report demonstrating that biodegradable polymer nanoparticles are effective delivery vehicles for siRNA in the vaginal mucosa. PMID:19404239

Radiation-induced gene expression in the nematode Caenorhabditis elegans

NASA Technical Reports Server (NTRS)

Nelson, Gregory A.; Jones, Tamako A.; Chesnut, Aaron; Smith, Anna L.

2002-01-01

We used the nematode C. elegans to characterize the genotoxic and cytotoxic effects of ionizing radiation in a simple animal model emphasizing the unique effects of charged particle radiation. Here we demonstrate by RT-PCR differential display and whole genome microarray hybridization experiments that gamma rays, accelerated protons and iron ions at the same physical dose lead to unique transcription profiles. 599 of 17871 genes analyzed (3.4%) showed differential expression 3 hrs after exposure to 3 Gy of radiation. 193 were up-regulated, 406 were down-regulated and 90% were affected only by a single species of radiation. A novel statistical clustering technique identified the regulatory relationships between the radiation-modulated genes and showed that genes affected by each radiation species were associated with unique regulatory clusters. This suggests that independent homeostatic mechanisms are activated in response to radiation exposure as a function of track structure or ionization density.

Mechanisms of Low Dose Radiation-induced T helper Cell Function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gridley, Daila S.

Exposure to radiation above levels normally encountered on Earth can occur during wartime, accidents such as those at Three Mile Island and Chernobyl, and detonation of “dirty bombs” by terrorists. Relatively high levels of radiation exposure can also occur in certain occupations (low-level waste sites, nuclear power plants, nuclear medicine facilities, airline industry, and space agencies). Depression or dysfunction of the highly radiosensitive cells of the immune system can lead to serious consequences, including increased risk for infections, cancer, hypersensitivity reactions, poor wound healing, and other pathologies. The focus of this research was on the T helper (Th) subset ofmore » lymphocytes that secrete cytokines (proteins), and thus control many actions and interactions of other cell types that make up what is collectively known as the immune system. The Department of Energy (DOE) Low Dose Radiation Program is concerned with mechanisms altered by exposure to high energy photons (x- and gamma-rays), protons and electrons. This study compared, for the first time, the low-dose effects of two of these radiation forms, photons and protons, on the response of Th cells, as well as other cell types with which they communicate. The research provided insights regarding gene expression patterns and capacity to secrete potent immunostimulatory and immunosuppressive cytokines, some of which are implicated in pathophysiological processes. Furthermore, the photon versus proton comparison was important not only to healthy individuals who may be exposed, but also to patients undergoing radiotherapy, since many medical centers in the United States, as well as worldwide, are now building proton accelerators. The overall hypothesis of this study was that whole-body exposure to low-dose photons (gamma-rays) will alter CD4+ Th cell function. We further proposed that exposure to low-dose proton radiation will induce a different pattern of gene and functional changes compared to photons. Over the course of this research, tissues other than spleens were archived and with funding obtained from other sources, including the Department of Radiation Medicine at the Loma Linda University Medical Center, some additional assays were performed. Furthermore, groups of additional mice were included that were pre-exposed to low-dose photons before irradiating with acute photons, protons, and simulated solar particle event (SPE) protons. Hence, the original support together with the additional funding for our research led to generation of much valuable information that was originally not anticipated. Some of the data has already resulted in published articles, manuscripts in review, and a number of presentations at scientific conferences and workshops. Difficulties in reliable and reproducible quantification of secreted cytokines using multi-plex technology delayed completion of this study for a period of time. However, final analyses of the remaining data are currently being performed and should result in additional publications and presentations in the near future. Some of the most notable conclusions, thus far, are briefly summarized below: - Distribution of leukocytes were dependent upon cell type, radiation quality, body compartment analyzed, and time after exposure. Low-dose protons tended to have less effect on numbers of major leukocyte populations and T cell subsets compared to low-dose photons. - The patterns of gene and cytokine expression in CD4+ T cells after protracted low-dose irradiation were significantly modified and highly dependent upon the total dose and time after exposure. - Patterns of gene and cytokine expression differed substantially among groups exposed to low-dose photons versus low-dose protons; differences were also noted among groups exposed to much higher doses of photons, protons, and simulated SPE protons. - Some measurements indicated that exposure to low-dose photon radiation, especially 0.01 Gy, significantly “normalized” at least some adverse effects of simulated SPE protons, thereby suggesting that this low level of radiation may induce protective mechanisms against a relatively large radiation event. - Analysis of signal transduction pathways in CD4+ T cells showed that whole-body priming with 0.01 Gy photons before exposure to simulated SPE protons significantly increased expression of p38MAPK and NF-kappaB, while JNK expression was decreased. Overall, it appears that the p38MAPK signaling pathway may be most important in inducing a radioprotective response.« less

Imidacloprid exposure cause the histopathological changes, activation of TNF-α, iNOS, 8-OHdG biomarkers, and alteration of caspase 3, iNOS, CYP1A, MT1 gene expression levels in common carp (Cyprinus carpio L.).

PubMed

Özdemir, Selçuk; Altun, Serdar; Arslan, Harun

2018-01-01

Imidacloprid (IMI) is a neonicotinoid that is widely used for the protection of crops and carnivores from insects and parasites, respectively. It is well known that imidacloprid exposure has a harmful effect on several organisms. However, there is little information about imidacloprid toxicity in aquatic animals, particularly fish. Thus, in the current study, we assessed the histopathological changes; activation of iNOS, 8-OHdG and TNF-α; and expression levels of caspase 3, iNOS, CYP1A and MT1 genes in the common carp exposed to imidacloprid. For this purpose, fish were exposed to either a low dose (140 mg/L) or a high dose (280 mg/L) of imidacloprid for 24 h, 48 h, 72 h and 96 h. After IMI exposure, we detected hyperplasia of secondary lamellar cells and mucous cell hyperplasia in the gills, as well as hydropic degeneration in hepatocytes and necrosis in the liver. Moreover, 8-OHdG, iNOS and TNF-α activation was found particularly in the gills and liver but also moderately in the brain. Transcriptional analysis showed that caspase 3 expression was altered low dose and high doses of IMI for 72 h and 96 h exposure ( p <  0.05), iNOS expression was up-regulated with both low and high doses of IMI and in a time-dependent manner ( p <  0.05, p <  0.01, p <  0.001), CYP1A expression was not significantly changed regardless of the dose of IMI and exposure time ( p >  0.05) except with low and high doses of IMI for 96 h ( p <  0.05), and lastly, MT1 gene expression was up-regulated only in the brain with low doses of IMI for 96 h and high doses of IMI for 48 h, 72 h and 96 h exposure ( p <  0.05, p <  0.01). Our results indicated that acute IMI exposure moderately induce apoptosis in the brain but caused severe histopathological lesions, inflammation, and oxidative stress in the gills, liver, and brain of the common carp.

Transcriptional profiles in liver from rats treated with tumorigenic and non-tumorigenic triazole conazole fungicides: Propiconazole, triadimefon, and myclobutanil.

PubMed

Hester, Susan D; Wolf, Douglas C; Nesnow, Stephen; Thai, Sheau-Fung

2006-01-01

Conazoles are a class of fungicides used as pharmaceutical and agricultural agents. In chronic bioassays in rats, triadimefon was hepatotoxic and induced follicular cell adenomas in the thyroid gland, whereas, propiconazole and myclobutanil were hepatotoxic but had no effect on the thyroid gland. These conazoles administered in the feed to male Wistar/Han rats were found to induce hepatomegaly, induce high levels of pentoxyresorufin-O-dealkylase, increase cell proliferation in the liver, increase serum cholesterol, decrease serum T3 and T4, and increase hepatic uridine diphosphoglucuronosyl transferase activity. The goal of the present study was to define pathways that explain the biologic outcomes. Male Wistar/Han rats (3 per group), were exposed to the 3 conazoles in the feed for 4, 30, or 90 days of treatment at tumorigenic and nontumorigenic doses. Hepatic gene expression was determined using high-density Affymetrix GeneChips (Rat 230_2). Differential gene expression was assessed at the probe level using Robust Multichip Average analysis. Principal component analysis by treatment and time showed within group sample similarity and that the treatment groups were distinct from each other. The number of altered genes varied by treatment, dose, and time. The greatest number of altered genes was induced by triadimefon and propiconazole after 90 days of treatment, while myclobutanil had minimal effects at that time point. Pathway level analyses revealed that after 90 days of treatment the most significant numbers of altered pathways were related to cell signaling, growth, and metabolism. Pathway level analysis for triadimefon and propiconazole resulted in 71 altered pathways common to both chemicals. These pathways controlled cholesterol metabolism, activation of nuclear receptors, and N-ras and K-ras signaling. There were 37 pathways uniquely changed by propiconazole, and triadimefon uniquely altered 34 pathways. Pathway level analysis of altered gene expression resulted in a more complete description of the associated toxicological effects that can distinguish triadimefon from propiconazole and myclobutanil.

Atorvastatin inhibits the immediate-early response gene EGR1 and improves the functional pro of CD4+T-lymphocytes in acute coronary syndromes

PubMed Central

Campioni, Mara; Flego, Davide; Angelini, Giulia; Pedicino, Daniela; Giglio, Ada Francesca; Trotta, Francesco; Giubilato, Simona; Pazzano, Vincenzo; Lucci, Claudia; Iaconelli, Antonio; Ruggio, Aureliano; Biasucci, Luigi Marzio

2017-01-01

Background- Adaptive immune-response is associated with a worse outcome in acute coronary syndromes. Statins have anti-inflammatory activity beyond lowering lipid levels. We investigated the effects of ex-vivo and in-vivo atorvastatin treatment in acute coronary syndromes on CD4+T-cells, and the underlying molecular mechanisms. Approach and results- Blood samples were collected from 50 statin-naïve acute coronary syndrome patients. We assessed CD4+T-cell activation by flow-cytometry, the expression of 84 T-helper transcription-factors and 84 T-cell related genes by RT-qPCR, and protein expression by Western-blot, before and after 24-hours incubation with increasing doses of atorvastatin: 3-10-26 g/ml (corresponding to blood levels achieved with doses of 10-40-80 mg, respectively). After incubation, we found a significant decrease in interferon-?-producing CD4+CD28nullT-cells (P = 0.009) and a significant increase in interleukin-10-producing CD4+CD25highT-cells (P < 0.001). Atorvastatin increased the expression of 2 genes and decreased the expression of 12 genes (in particular, EGR1, FOS,CCR2 and toll like receptor-4; >3-fold changes). The in-vivo effects of atorvastatin were analyzed in 10 statin-free acute coronary syndrome patients at baseline, and after 24h and 48h of atorvastatin therapy (80 mg/daily): EGR1-gene expression decreased at 24h (P = 0.01) and 48h (P = 0.005); EGR1-protein levels decreased at 48h (P = 0.03). Conclusions-In acute coronary syndromes, the effects of atorvastatin on immune system might be partially related to the inhibition of the master regulator gene EGR1. Our finding might offer a causal explanation on why statins improve the early outcome in acute coronary syndromes. PMID:28407684

Effects of glucose, insulin and triiodothyroxine on leptin and leptin receptor expression and the effects of leptin on activities of enzymes related to glucose metabolism in grass carp (Ctenopharyngodon idella) hepatocytes.

PubMed

Lu, Rong-Hua; Zhou, Yi; Yuan, Xiao-Chen; Liang, Xu-Fang; Fang, Liu; Bai, Xiao-Li; Wang, Min; Zhao, Yu-Hua

2015-08-01

Leptin is an important regulator of appetite and energy expenditure in mammals, but its role in fish metabolism control is poorly understood. Our previous studies demonstrated that leptin has an effect on the regulation of food intake and energy expenditure as well as lipid metabolism (stimulation of lipolysis and inhibition of adipogenesis) in the grass carp Ctenopharyngodon idella. To further investigate the role of leptin in fish, the effects of glucose, insulin and triiodothyroxine (T3) on the expression levels of leptin and leptin receptor (Lepr) and the effects of leptin on the activities of critical glucose metabolism enzymes in grass carp hepatocytes were evaluated in the present study. Our data indicated that leptin gene expression was induced by glucose in a dose-dependent manner, while Lepr gene expression exhibited a biphasic change. A high dose of insulin (100 ng/mL) significantly up-regulated the expression of leptin and Lepr. Leptin expression was markedly up-regulated by a low concentration of T3 but inhibited by a high concentration of T3. T3 up-regulated Lepr expression in a dose-dependent manner. Together, these data suggest that leptin had a close relationship with three factors (glucose, insulin and T3) and might participate in the regulation of glucose metabolism in grass carp. In addition, we also found that leptin affected the activities of key enzymes that are involved in glucose metabolism, which might be mediated by insulin receptor substrate-phosphoinositol 3-kinase signaling.

Overexpression of variant PNPLA3 gene at I148M position causes malignant transformation of hepatocytes via IL-6-JAK2/STAT3 pathway in low dose free fatty acid exposure: a laboratory investigation in vitro and in vivo

PubMed Central

Liu, Zhengtao; Chen, Tianchi; Lu, Xiaoxiao; Xie, Haiyang; Zhou, Lin; Zheng, Shusen

2016-01-01

Epidemiological survey identified that the variant patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene at I148M position exerts direct effect in promoting hepatocellular carcinoma (HCC) under extraneous oxidative stress by interaction with obesity. However, the mechanism is still unknown. HepG2 cells were overexpressed by transinfection of PNPLA3 with wild-type 148I (PNPLA3WT) and mutant 148M (PNPLA3I148M), respectively. Variation in metabolic indicators, hepatic steatosis, biological behaviors and signaling molecules related to cancer promotion was measured in hepatocytes using low-dose free fatty acid (FFA) exposure. Effect of PNPLA3I148M on xenograft biology and its interaction with dietary obesity were also evaluated in animal study. Cells overexpresssing PNPLA3I148M in low-dose FFA incubation showed more proliferation, migration, invasion, and less apoptosis (P<0.05). Low-dose FFA specifically activated JAK2/STAT3 phosphorylation of PNPLA3I148M cells via upregulation of interleukin-6. Animal study showed high-fat diet accelerated growth of xenografts derived from PNPLA3I148M cells incubated in low-dose FFA. In low oxidative stress, PNPLA3I148M initiated the hepatocyte malignant transformation through the activation of inflammation-mediated JAK/STAT pathway. Dietary obesity amplified the growth of tumor from PNPLA3I148M cells by interaction with local FFA incubation. Anti-inflammation and weight loss might be potential approaches for preventing HCC in high-risk population carrying PNPLA3 variant. PMID:27186262

Overexpression of variant PNPLA3 gene at I148M position causes malignant transformation of hepatocytes via IL-6-JAK2/STAT3 pathway in low dose free fatty acid exposure: a laboratory investigation in vitro and in vivo.

PubMed

Liu, Zhengtao; Chen, Tianchi; Lu, Xiaoxiao; Xie, Haiyang; Zhou, Lin; Zheng, Shusen

2016-01-01

Epidemiological survey identified that the variant patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene at I148M position exerts direct effect in promoting hepatocellular carcinoma (HCC) under extraneous oxidative stress by interaction with obesity. However, the mechanism is still unknown. HepG2 cells were overexpressed by transinfection of PNPLA3 with wild-type 148I (PNPLA3(WT)) and mutant 148M (PNPLA3(I148M)), respectively. Variation in metabolic indicators, hepatic steatosis, biological behaviors and signaling molecules related to cancer promotion was measured in hepatocytes using low-dose free fatty acid (FFA) exposure. Effect of PNPLA3(I148M) on xenograft biology and its interaction with dietary obesity were also evaluated in animal study. Cells overexpresssing PNPLA3(I148M) in low-dose FFA incubation showed more proliferation, migration, invasion, and less apoptosis (P<0.05). Low-dose FFA specifically activated JAK2/STAT3 phosphorylation of PNPLA3(I148M) cells via upregulation of interleukin-6. Animal study showed high-fat diet accelerated growth of xenografts derived from PNPLA3(I148M) cells incubated in low-dose FFA. In low oxidative stress, PNPLA3(I148M) initiated the hepatocyte malignant transformation through the activation of inflammation-mediated JAK/STAT pathway. Dietary obesity amplified the growth of tumor from PNPLA3(I148M) cells by interaction with local FFA incubation. Anti-inflammation and weight loss might be potential approaches for preventing HCC in high-risk population carrying PNPLA3 variant.

Diverse effects of dimethyl sulfoxide (DMSO) on the differentiation potential of human embryonic stem cells.

PubMed

Pal, Rajarshi; Mamidi, Murali Krishna; Das, Anjan Kumar; Bhonde, Ramesh

2012-04-01

In vitro disease modeling using pluripotent stem cells can be a fast track screening tool for toxicological testing of candidate drug molecules. Dimethyl sulfoxide (DMSO) is one of the most commonly used solvents in drug screening. In the present investigation, we exposed 14- to 21-day-old embryoid bodies (EBs) to three different concentrations of DMSO [0.01% (low dose), 0.1% (medium dose) and 1.0% (high dose)] to identify the safest dose that could effectively be used as solvent. We found that DMSO treatment substantially altered the morphology and attachment of cells in concurrence with a significant reduction in cell viability in a dose-dependent manner. Gene expression studies revealed a selective downregulation of key markers associated with stemness (Oct-4, Sox-2, Nanog and Rex-1); ectoderm (Nestin, TuJ1, NEFH and Keratin-15); mesoderm (HAND-1, MEF-2C, GATA-4 and cardiac-actin); and endoderm (SOX-17, HNF-3β, GATA-6 and albumin), indicating an aberrant and untimely differentiation trajectory. Furthermore, immunocytochemistry, flow cytometry and histological analyses demonstrated substantial decrease in the levels of albumin and CK-18 proteins coupled with a massive reduction in the number of cells positive for PAS staining, implicating reduced deposits of glycogen. Our study advocates for the first time that DMSO exposure not only affects the phenotypic characteristics but also induces significant alteration in gene expression, protein content and functionality of the differentiated hepatic cells. Overall, our experiments warrant that hESC-based assays can provide timely alerts about the outcome of widespread applications of DMSO as drug solvent, cryoprotectant and differentiating agent.

Ethanol extract of Peperomia pellucida (Piperaceae) promotes fracture healing by an anabolic effect on osteoblasts.

PubMed

Ngueguim, Florence Tsofack; Khan, Mohd Parvez; Donfack, Jean Hubert; Tewari, Deepshikha; Dimo, Theophile; Kamtchouing, Pierre; Maurya, Rakesh; Chattopadhyay, Naibedya

2013-06-21

The whole plant or some part of Peperomia pellucida (L.) HBK is used in some parts of Cameroon as a treatment for fracture healing. To evaluate the effect of ethanolic extracts of Peperomia pellucida (L.), a Cameroonian medicinal plant on bone regeneration following bone and marrow injury, and determine the mode of action. Ethanol extract of Peperomia pellucida was administered at 100 and 200mg/kg doses orally to adult female Sprague-Dawley rats having a drill hole injury (0.8mm) in the femur diaphysis. Vehicle (gum-acacia in distilled water) was given to the control group. After 12 days of treatment, animals were euthanized and femur bones collected. Confocal microscopy of calcein labeling at the drill hole site was performed to evaluate bone regeneration. 3-D microarchitecture of drill hole site was analyzed by micorocomputed tomography. Osteogenic effects of the extract were evaluated by assessing mineralized nodule formation of bone marrow stromal cells and expression of osteogenic genes (mRNA level of type-1 collagen, bone morphogenetic protein-2 and osteocalcin genes) in the femur. Ethanol extract from Peperomia Pellucida (L.) dose-dependently induced bone regeneration at the fracture site. At 200mg/kg dose, the extract significantly increased mineral deposition compared to controls. The extract also improved microarchitecture of the regenerating bone evident from increased bone volume fraction, trabecular thickness, trabecular number, and decreased trabecular separation and structure model index. In addition, the extract increased the formation of mineralized nodules from the bone marrow stromal cells. Furthermore, the extract induced the expression of osteogenic genes in the femur including type 1 collagen, osteocalcin and BMP-2, compared to control. Ethanolic extract of P. pellucid (L.) accelerates fracture repair in rats via stimulatory effects on osteoblast differentiation and mineralization, thereby justifying its traditional use. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

DOUGLAS LEA MEMORIAL LECTURE: From targets to genes: a brief history of radiosensitivity

NASA Astrophysics Data System (ADS)

Steel, G. Gordon

1996-02-01

The biological work of Douglas Lea spanned the period from 1934 to his early death in 1947, and during this short period he made important contributions to the theory of radiation action. He interpreted experimental data relating to the effects of radiation on viruses, bacteria, bean roots, etc in terms of the inactivation of discrete targets, which he identified with cellular genes. He thus laid the foundation of much subsequent research. It is now well recognized that mammalian cells differ substantially in radiosensitivity, especially in the low-dose region of the survival curve. The dependence of radiosensitivity on dose rate has been widely studied; this has practical significance for clinical radiotherapy as well as mechanistic implications. Since Lea's time there have been a number of efforts to describe models that can relate cell killing to radiation dose, dose rate, and track structure. So far these have not led to a comprehensive and widely accepted picture. Microdosimetric considerations lead to the concept of differing severity of lesions induced in DNA. Much is known about the sequence of processes that subsequently lead to cell inactivation: this can be divided into phases of induction, processing, and manifestation. Chromosomal events are currently attracting much attention, as they did in Lea's time. Considerable progress has also been made in identifying genes that control the repair of radiation damage. It has been found that mutation is frequently associated with the loss of a large segment of the genome around the damage site and this will have important implications for interactive processes between particle tracks.

Heterogeneity in cancer cells: variation in drug response in different primary and secondary colorectal cancer cell lines in vitro.

PubMed

Arul, Melanie; Roslani, April Camilla; Cheah, Swee Hung

2017-05-01

Tumor heterogeneity may give rise to differential responses to chemotherapy drugs. Therefore, unraveling tumor heterogeneity has an implication for biomarker discovery and cancer therapeutics. To test this phenomenon, we investigated the differential responses of three secondary colorectal cancer cell lines of different origins (HCT116, HT29, and SW620 cells) and four novel primary cell lines obtained from different colorectal cancer patients to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP) and explored the differences in gene expression among the primary cell lines in response to exposure to cytotoxic drugs. Cells were exposed to different doses of 5-FU and L-OHP separately or in combinations of equitoxic drug or equimolar drug ratios (median effect of Chou-Talalay principle). Cell viability was assessed using MTT assay and the respective IC 50 values were determined. Changes in gene expression in primary cell lines after exposure to the same drug doses were compared using real-time PCR array. The sensitivities (IC 50 ) of different cell lines, both secondary and primary, to 5-FU and L-OHP were significantly different, whether in monotherapy or combined treatment. Primary cell lines needed higher doses to reach IC 50 . There were variations in gene expression among the primary cell lines of different chemosensitivities to the challenge of the same combined dose of 5-FU and L-OHP. The results confirm the heterogeneous nature of colorectal cancer cells from different patient tumors. Studies using primary cancer cells established from patient's tumors rather than secondary cell lines will more closely reflect the actual character of the disease.

Global Gene Expression Profiling in Lung Tissues of Rat Exposed to Lunar Dust Particles

NASA Technical Reports Server (NTRS)

Yeshitla, Samrawit A.; Lam, Chiu-Wing; Kidane, Yared H.; Feiveson, Alan H.; Ploutz-Snyder, Robert; Wu, Honglu; James, John T.; Meyers, Valerie E.; Zhang, Ye

2014-01-01

The Moon's surface is covered by a layer of fine, potential reactive dust. Lunar dust contain about 1-2% respirable very fine dust (less than 3 micrometers). The habitable area of any lunar landing vehicle and outpost would inevitably be contaminated with lunar dust that could pose a health risk. The purpose of the study is to analyze the dynamics of global gene expression changes in lung tissues of rats exposed to lunar dust particles. F344 rats were exposed for 4 weeks (6h/d; 5d/wk) in nose-only inhalation chambers to concentrations of 0 (control air), 2.1, 6.8, 21, and 61 mg/m3 of lunar dust. Animals were euthanized at 1 day and 13 weeks after the last inhalation exposure. After being lavaged, lung tissue from each animal was collected and total RNA was isolated. Four samples of each dose group were analyzed using Agilent Rat GE v3 microarray to profile global gene expression of 44K transcripts. After background subtraction, normalization, and log transformation, t tests were used to compare the mean expression levels of each exposed group to the control group. Correction for multiple testing was made using the method of Benjamini, Krieger, and Yekuteli (1) to control the false discovery rate. Genes with significant changes of at least 1.75 fold were identified as genes of interest. Both low and high doses of lunar dust caused dramatic, dose-dependent global gene expression changes in the lung tissues. However, the responses of lung tissue to low dose lunar dust are distinguished from those of high doses, especially those associated with 61mg/m3 dust exposure. The data were further integrated into the Ingenuity system to analyze the gene ontology (GO), pathway distribution and putative upstream regulators and gene targets. Multiple pathways, functions, and upstream regulators have been identified in response to lunar dust induced damage in the lung tissue.

X-ray irradiation has positive effects for the recovery of peripheral nerve injury maybe through the vascular smooth muscle contraction signaling pathway.

PubMed

Jiang, Bo; Zhang, Yong; She, Chang; Zhao, Jiaju; Zhou, Kailong; Zuo, Zhicheng; Zhou, Xiaozhong; Wang, Peiji; Dong, Qirong

2017-09-01

It is well known that moderate to high doses of ionizing radiation have a toxic effect on the organism. However, there are few experimental studies on the mechanisms of LDR ionizing radiation on nerve regeneration after peripheral nerve injury. We established the rats' peripheral nerve injury model via repaired Peripheral nerve injury nerve, vascular endothelial growth factor a and Growth associated protein-43 were detected from different treatment groups. We performed transcriptome sequencing focusing on investigating the differentially expressed genes and gene functions between the control group and 1Gy group. Sequencing was done by using high-throughput RNA-sequencing (RNA-seq) technologies. The results showed the 1Gy group to be the most effective promoting repair. RNA-sequencing identified 619 differently expressed genes between control and treated groups. A Gene Ontology analysis of the differentially expressed genes revealed enrichment in the functional pathways. Among them, candidate genes associated with nerve repair were identified. Pathways involved in cell-substrate adhesion, vascular smooth muscle contraction and cell adhesion molecule signaling may be involved in recovery from peripheral nerve injury. Copyright © 2017. Published by Elsevier B.V.

Modification of Flight and Locomotion Performances, Respiratory Metabolism, and Transcriptome Expression in the Lady Beetle Harmonia axyridis through Sublethal Pesticide Exposure

PubMed Central

Xiao, Da; Tan, Xiaoling; Wang, Wenjuan; Zhang, Fan; Desneux, Nicolas; Wang, Su

2017-01-01

Biological control is usually used in combination with chemical control for practical agricultural applications. Thus, the influence of insecticides on the natural predators used for biological control should be investigated for integrated pest management. The ladybird Harmonia axyridis is an effective predator on aphids and coccids. Beta-cypermethrin is a broad-spectrum insecticide used worldwide for controlling insect pests. H. axyridis is becoming increasingly threatened by this insecticide. Here, we investigated the effect of a sublethal dose of beta-cypermethrin on flight, locomotion, respiration, and detoxification system of H. axyridis. After exposure to beta-cypermethrin, succinic female adults flew more times, longer distances, and during longer time periods. Exposure to a sublethal dose of beta-cypermethrin also promoted an increase in walking rate, walking distance, walking duration, and also an increase in respiratory quotient and respiratory rate. To investigate the effects of beta-cypermethrin on H. axyridis detoxification system, we analyzed the transcriptome of H. axyridis adults, focusing on genes related to detoxification systems. De novo assembly generated 65,509 unigenes with a mean length of 799 bp. From these genes, 26,020 unigenes (40.91% of all unigenes) exhibited clear homology to known genes in the NCBI non-redundant database. In addition, 10,402 unigenes were annotated in the Cluster of Orthologous Groups database, 12,088 unigenes were assigned to the Gene Ontology database and 12,269 unigenes were in the Kyoto Encyclopedia of Genes and Genome (KEGG) database. Exposure to beta-cypermethrin had significant effects on the transcriptome profile of H. axyridis adult. Based on uniquely mapped reads, 3,296 unigenes were differentially expressed, 868 unigenes were up-regulated and 2,248 unigenes were down-regulated. We identified differentially-expressed unigenes related to general detoxification systems in H. axyridis. This assembled, annotated transcriptome provides a valuable genomic resource for further understanding the molecular basis of detoxification mechanisms in H. axyridis. PMID:28239355

Modification of Flight and Locomotion Performances, Respiratory Metabolism, and Transcriptome Expression in the Lady Beetle Harmonia axyridis through Sublethal Pesticide Exposure.

PubMed

Xiao, Da; Tan, Xiaoling; Wang, Wenjuan; Zhang, Fan; Desneux, Nicolas; Wang, Su

2017-01-01

Biological control is usually used in combination with chemical control for practical agricultural applications. Thus, the influence of insecticides on the natural predators used for biological control should be investigated for integrated pest management. The ladybird Harmonia axyridis is an effective predator on aphids and coccids. Beta-cypermethrin is a broad-spectrum insecticide used worldwide for controlling insect pests. H. axyridis is becoming increasingly threatened by this insecticide. Here, we investigated the effect of a sublethal dose of beta-cypermethrin on flight, locomotion, respiration, and detoxification system of H. axyridis . After exposure to beta-cypermethrin, succinic female adults flew more times, longer distances, and during longer time periods. Exposure to a sublethal dose of beta-cypermethrin also promoted an increase in walking rate, walking distance, walking duration, and also an increase in respiratory quotient and respiratory rate. To investigate the effects of beta-cypermethrin on H. axyridis detoxification system, we analyzed the transcriptome of H. axyridis adults, focusing on genes related to detoxification systems. De novo assembly generated 65,509 unigenes with a mean length of 799 bp. From these genes, 26,020 unigenes (40.91% of all unigenes) exhibited clear homology to known genes in the NCBI non-redundant database. In addition, 10,402 unigenes were annotated in the Cluster of Orthologous Groups database, 12,088 unigenes were assigned to the Gene Ontology database and 12,269 unigenes were in the Kyoto Encyclopedia of Genes and Genome (KEGG) database. Exposure to beta-cypermethrin had significant effects on the transcriptome profile of H. axyridis adult. Based on uniquely mapped reads, 3,296 unigenes were differentially expressed, 868 unigenes were up-regulated and 2,248 unigenes were down-regulated. We identified differentially-expressed unigenes related to general detoxification systems in H. axyridis . This assembled, annotated transcriptome provides a valuable genomic resource for further understanding the molecular basis of detoxification mechanisms in H. axyridis .

In vitro effects of Apixaban on 5 different cancer cell lines

PubMed Central

Guasti, Luigina; Moretto, Paola; Vigetti, Davide; Ageno, Walter; Dentali, Francesco; Maresca, Andrea M.; Campiotti, Leonardo; Grandi, Anna M.; Passi, Alberto

2017-01-01

Background Cancer is associated with hypercoagulability. However, several data suggest that anticoagulant drugs may have an effect on tumor development and progression mediated by both coagulation dependent processes and non-coagulation dependent processes. Therefore, we investigated the in vitro effects of Apixaban on cell proliferation, mortality, cell migration, gene expression and matrix metalloproteinase in 5 different cancer cell lines. Methods The following cancer cell lines, and 2 normal fibroblast cultures (lung and dermal fibroblasts), were studied: OVCAR3 (ovarian cancer), MDA MB 231 (breast cancer), CaCO-2 (colon cancer), LNCaP (prostate cancer) and U937 (histiocytic lymphoma). Proliferation and cell mortality were assessed in control cells and Apixaban treated cultures (dose from 0.1 to 5 μg/ml, 0 to 96-h). Necrosis/Apoptosis (fluorescence microscopy), cell migration (24-h after scratch test), matrix metalloproteinase (MMP) activity and mRNA expression (RT PCR) of p16, p21, p53 and HAS were also assessed. Results High-dose (5 μg/ml) Apixaban incubation was associated with a significantly reduced proliferation in 3 cancer cell lines (OVCAR3, CaCO-2 and LNCaP) and with increased cancer cell mortality in all, except LNCaP, cancer lines. Apoptosis seems to account for the increased mortality. The migration capacity seems to be impaired after high-dose Apixaban incubation in OVCAR3 and CaCO-2 cells. Data on mRNA expression suggest a consistent increase in tumor suppression gene p16 in all cell lines. Conclusions Our data suggest that high-dose Apixaban may be able to interfere with cancer cell in vitro, reducing proliferation and increasing cancer cell mortality through apoptosis in several cancer cell lines. PMID:29023465

High-Dose Vitamin D3 during Tuberculosis Treatment in Mongolia. A Randomized Controlled Trial.

PubMed

Ganmaa, Davaasambuu; Munkhzul, Baatar; Fawzi, Wafaie; Spiegelman, Donna; Willett, Walter C; Bayasgalan, Purev; Baasansuren, Erkhembayar; Buyankhishig, Burneebaatar; Oyun-Erdene, Sereeter; Jolliffe, David A; Xenakis, Theodoros; Bromage, Sabri; Bloom, Barry R; Martineau, Adrian R

2017-09-01

Existing trials of adjunctive vitamin D in the treatment of pulmonary tuberculosis (PTB) are variously limited by small sample sizes, inadequate dosing regimens, and high baseline vitamin D status among participants. Comprehensive analyses of the effects of genetic variation in the vitamin D pathway on response to vitamin D supplementation are lacking. To determine the effect of high-dose vitamin D 3 on response to antimicrobial therapy for PTB and to evaluate the influence of single-nucleotide polymorphisms (SNPs) in vitamin D pathway genes on response to adjunctive vitamin D 3 . We conducted a clinical trial in 390 adults with PTB in Ulaanbaatar, Mongolia, who were randomized to receive four biweekly doses of 3.5 mg (140,000 IU) vitamin D 3 (n = 190) or placebo (n = 200) during intensive-phase antituberculosis treatment. The intervention elevated 8-week serum 25-hydroxyvitamin D concentrations (154.5 nmol/L vs. 15.2 nmol/L in active vs. placebo arms, respectively; 95% confidence interval for difference, 125.9-154.7 nmol/L; P < 0.001) but did not influence time to sputum culture conversion overall (adjusted hazard ratio, 1.09; 95% confidence interval, 0.86-1.36; P = 0.48). Adjunctive vitamin D 3 accelerated sputum culture conversion in patients with one or more minor alleles for SNPs in genes encoding the vitamin D receptor (rs4334089, rs11568820) and 25-hydroxyvitamin D 1α-hydroxylase (CYP27B1: rs4646536) (adjusted hazard ratio ≥ 1.47; P for interaction ≤ 0.02). Vitamin D 3 did not influence time to sputum culture conversion in the study population overall. Effects of the intervention were modified by SNPs in VDR and CYP27B1. Clinical trial registered with www.clinicaltrials.gov (NCT01657656).

VITELLOGENIN GENE EXPRESSION IN FATHEAD MINNOWS EXPOSED TO EE2 IN A WHOLE LAKE DOSING EXPERIMENT

EPA Science Inventory

A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA), northwestern Ontario in 2001 and 2002. This experiment examined population, organism, biochemical and cellular-level effects in lake trout, white sucke...

Impact assessment of bisphenol A on lignin-modifying enzymes by basidiomycete Trametes versicolor.

PubMed

Takamiya, Minako; Magan, Naresh; Warner, Philip J

2008-06-15

The impact of different concentrations of bisphenol A (BPA) was evaluated on growth of the white-rot basidiomycete, Trametes versicolor, and on the expression of genes encoding lignin-modifying enzyme (LME) activities. Effective doses (EDs) were obtained from fungal growth rate to monitor LME activities and the expression levels of their encoding genes. The fungus showed mycelial growth at concentrations of up to 300 microg ml(-1) of BPA with an ED50 value of 185 microg ml(-1). The LME activities were stimulated by BPA concentrations up to 300 microg ml(-1). The lignin peroxidase (LIP) encoding gene may be sensitive to BPA stress.

Systems toxicology identifies mechanistic impacts of 2-amino-4,6-dinitrotoluene (2A-DNT) exposure in Northern Bobwhite.

PubMed

Gust, Kurt A; Nanduri, Bindu; Rawat, Arun; Wilbanks, Mitchell S; Ang, Choo Yaw; Johnson, David R; Pendarvis, Ken; Chen, Xianfeng; Quinn, Michael J; Johnson, Mark S; Burgess, Shane C; Perkins, Edward J

2015-08-07

A systems toxicology investigation comparing and integrating transcriptomic and proteomic results was conducted to develop holistic effects characterizations for the wildlife bird model, Northern bobwhite (Colinus virginianus) dosed with the explosives degradation product 2-amino-4,6-dinitrotoluene (2A-DNT). A subchronic 60 d toxicology bioassay was leveraged where both sexes were dosed via daily gavage with 0, 3, 14, or 30 mg/kg-d 2A-DNT. Effects on global transcript expression were investigated in liver and kidney tissue using custom microarrays for C. virginianus in both sexes at all doses, while effects on proteome expression were investigated in liver for both sexes and kidney in males, at 30 mg/kg-d. As expected, transcript expression was not directly indicative of protein expression in response to 2A-DNT. However, a high degree of correspondence was observed among gene and protein expression when investigating higher-order functional responses including statistically enriched gene networks and canonical pathways, especially when connected to toxicological outcomes of 2A-DNT exposure. Analysis of networks statistically enriched for both transcripts and proteins demonstrated common responses including inhibition of programmed cell death and arrest of cell cycle in liver tissues at 2A-DNT doses that caused liver necrosis and death in females. Additionally, both transcript and protein expression in liver tissue was indicative of induced phase I and II xenobiotic metabolism potentially as a mechanism to detoxify and excrete 2A-DNT. Nuclear signaling assays, transcript expression and protein expression each implicated peroxisome proliferator-activated receptor (PPAR) nuclear signaling as a primary molecular target in the 2A-DNT exposure with significant downstream enrichment of PPAR-regulated pathways including lipid metabolic pathways and gluconeogenesis suggesting impaired bioenergetic potential. Although the differential expression of transcripts and proteins was largely unique, the consensus of functional pathways and gene networks enriched among transcriptomic and proteomic datasets provided the identification of many critical metabolic functions underlying 2A-DNT toxicity as well as impaired PPAR signaling, a key molecular initiating event known to be affected in di- and trinitrotoluene exposures.

Prostate Cancer Risk and DNA Methylation Signatures in Aging Rats following Developmental BPA Exposure: A Dose-Response Analysis.

PubMed

Prins, Gail S; Ye, Shu-Hua; Birch, Lynn; Zhang, Xiang; Cheong, Ana; Lin, Han; Calderon-Gierszal, Esther; Groen, Jacob; Hu, Wen-Yang; Ho, Shuk-Mei; van Breemen, Richard B

2017-07-11

Previous studies have uncovered heightened prostatic susceptibility to hormone-induced neoplasia from early-life exposure to low-dose bisphenol A (BPA). However, significant data gaps remain that are essential to address for biological relevance and necessary risk assessment. A complete BPA dose-response analysis of prostate lesions across multiple prostatic lobes was conducted that included internal BPA dosimetry, progression to adenocarcinoma with aging and mechanistic connections to epigenetically reprogramed genes. Male neonatal Sprague-Dawley rats were briefly exposed to 0.1 to 5,000 μg BPA/kg BW on postnatal days (PND) 1, 3, and 5. Individual prostate lobes plus periurethral prostatic ducts were evaluated at 7 mo or 1 y of age without or with adult testosterone plus estradiol (T+E) to promote carcinogenesis. DNA methylation of five genes was quantified by bisulfite genomic sequencing in d-200 dorsal prostates across BPA doses. Serum free-BPA and BPA-glucuronide were quantitated in sera of individual PND 3 pups collected 1 hr postexposure utilizing ultra-high-pressure tandem mass spectrometry (UHPLC-MS-MS). The lowest BPA dose initiated maximal hormonal carcinogenesis in lateral prostates despite undetectable free BPA 1 hr postexposure. Further, prostatic intraepithelial neoplasia (PIN) progressed to carcinoma in rats given neonatal low-dose BPA with adult T+E but not in rats given adult T+E alone. The dorsal and ventral lobes and periurethral prostatic ducts exhibited a nonmonotonic dose response with peak PIN, proliferation and apoptotic values at 10–100 μg/kg BW. This was paralleled by nonmonotonic and dose-specific DNA hypomethylation of genes that confer carcinogenic risk, with greatest hypomethylation at the lowest BPA doses. Developmental BPA exposures heighten prostate cancer susceptibility in a complex dose- and lobe-specific manner. Importantly, elevated carcinogenic risk is found at doses that yield undetectable serum free BPA. Dose-specific epigenetic modifications of selected genes provide a mechanistic framework that may connect early-life BPA to later-life predisposition to prostate carcinogenesis. https://doi.org/10.1289/EHP1050.

Triazole induced concentration-related gene signatures in rat whole embryo culture.

PubMed

Robinson, Joshua F; Tonk, Elisa C M; Verhoef, Aart; Piersma, Aldert H

2012-09-01

Commonly used as antifungal agents in agriculture and medicine, triazoles have been shown to cause teratogenicity in a diverse set of animal models. Here, we evaluated the dose-dependent impacts of flusilazole, cyproconazole and triadimefon, on global gene expression in relation to effects on embryonic development using the rat whole embryo culture (WEC) model. After 4 h exposure, we identified changes in gene expression due to triazole exposure which preceded morphological alterations observed at 48 h. In general, across the three triazoles, we observed similar directionality of regulation in gene expression and the magnitude of effects on gene expression correlated with the degree of induced developmental toxicity. Significantly regulated genes included key members of steroid/cholesterol and retinoic acid metabolism and hindbrain developmental pathways. Direct comparisons with previous studies suggest that triazole-gene signatures identified in the WEC overlap with zebrafish and mouse, and furthermore, triazoles impact gene expression in a similar manner as retinoic acid exposures in rat embryos. In summary, we further differentiate pathways underlying triazole-developmental toxicity using WEC and demonstrate the conservation of these response-pathways across model systems. Copyright © 2012 Elsevier Inc. All rights reserved.

DEHP (DI-N-ETHYLHEXYL PHTHALATE), WHEN ADMINISTERED DURING SEXUAL DIFFERENTIATION, INDUCES DOSE DEPENDENT DECREASES IN FETAL TESTIS GENE EXPRESSION AND STEROID HORMONE SYNTHESIS

EPA Science Inventory

DEHP (di-n-ethylhexyl phthalate), when administered during sexual differentiation, induces dose dependent decreases in fetal testis gene expression and steroid hormone synthesis.
Vickie S. Wilson, Christy Lambright, Johnathan Furr, Kathy Bobseine, Carmen Wood, Gary Held, and ...

Radiation Gene-expression Signatures in Primary Breast Cancer Cells.

PubMed

Minafra, Luigi; Bravatà, Valentina; Cammarata, Francesco P; Russo, Giorgio; Gilardi, Maria C; Forte, Giusi I

2018-05-01

In breast cancer (BC) care, radiation therapy (RT) is an efficient treatment to control localized tumor. Radiobiological research is needed to understand molecular differences that affect radiosensitivity of different tumor subtypes and the response variability. The aim of this study was to analyze gene expression profiling (GEP) in primary BC cells following irradiation with doses of 9 Gy and 23 Gy delivered by intraoperative electron radiation therapy (IOERT) in order to define gene signatures of response to high doses of ionizing radiation. We performed GEP by cDNA microarrays and evaluated cell survival after IOERT treatment in primary BC cell cultures. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to validate candidate genes. We showed, for the first time, a 4-gene and a 6-gene signature, as new molecular biomarkers, in two primary BC cell cultures after exposure at 9 Gy and 23 Gy respectively, for which we observed a significantly high survival rate. Gene signatures activated by different doses of ionizing radiation may predict response to RT and contribute to defining a personalized biological-driven treatment plan. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Aniline exposure associated with up-regulated transcriptional responses of three glutathione S-transferase Delta genes in Drosophila melanogaster.

PubMed

Chan, Wen-Chiao; Chien, Yi-Chih; Chien, Cheng-I

2015-03-01

Complex transcriptional profile of glutathione S-transferase Delta cluster genes occurred in the developmental process of the fruit fly Drosophila melanogaster. The purpose of this project was to quantify the expression levels of Gst Delta class genes altered by aniline exposure and to understand the relationship between aniline dosages and the variation of Gst Delta genes expressed in D. melanogaster. Using RT-PCR expression assays, the expression patterns of the transcript mRNAs of the glutathione S-transferase Delta genes were revealed and their expression levels were measured at eggs, larvae, pupae and adults. The adult stage was selected for further dose-response assays. After analysis, the results indicated that three Gst Delta genes (Gst D2, Gst D5 and Gst D6) were found to show a peak of up-regulated transcriptional response at 6-8h of exposure of aniline. Furthermore, the dose-response relationship of their induction levels within the dose regiments (from 1.2 to 2.0 μl/tube) had been measured. The expression patterns and annotations of these genes were discussed in the context. Copyright © 2015 Elsevier B.V. All rights reserved.

[The role of homeobox B2 gene in vascular endothelial proliferation and the protective effects of VEGF on the endothelia against radiation injury].

PubMed

Liu, Xu-sheng; Zhang, Xiao-qi; Liu, Liang; Ming, Jia; Xu, Hui; Ran, Xin-ze; Cheng, Tian-min

2004-10-01

To explore the role of HOXB2 gene in the proliferation of primary human umbilical vein endothelial cells (HUVECs) and the protective effects of VEGF on the endothelia against radiation injury. HUVECs were isolated, cultured, subcultured and identified. (1) Liposome coated oligodeoxynucleotide (odn) and homeoboxB2 antisense oligodeoxyncleotide (HOXB2asodn) were prepared prepared in the concentrations of 0.25, 0.5, 1.0 and 2.5 mg/L for the stimulation of HUVEC. (3)H-TdR incorporation test and MTT method were employed to determine the proliferation activity of HUVECs after activation. The cell cycle analysis of HUVECs was determined by flow cytometry. The expression level of HOXB2mRNA within HUVECs was detected by RT-PCR (reverse transcription polymerase chain reaction). (2) HUVECs were separately treated with the addition of VEGF in concentration of 50 microg/L, by radiation in the dose of 6 Gy or 12 Gy (60)Co gamma gamma ray, or radiation with 12 Gy (60)Co gamma gamma ray followed by the addition of VEGF in dose of 50 microg/L. The cellular morphology was observed and the cellular proliferation activity was determined by MTT method. (1) The proliferation activity of HUVECs could be markedly inhibited by liposome coated HOXB2asodn in comparison to liposome-odn (P < 0.05 or 0.001), and the inhibition effect was positively correlated with the increase in asodn concentration. The cell ratio in S phase and the expression level of the HOXB2mRNA could be lowered by asodn in dose of 2.5 mg/L (P < 0.05 or 0.001). (2) Radiation by (60)Co gamma ray could lead to the nuclear enlargement, vacuolation in the cytoplasm, multiplicity of nucleus and nuclear swelling. The proliferative activity of HUVECs was increased from 0.365 +/- 0.047 and 0.487 +/- 0.022 without radiation to 0.557 +/- 0.042 and 0.648 +/- 0.021 24 and 48 hours after 6 Gy radiation However it was decreased to 0.263 +/- 0.038 and 0.306 +/- 0.024 (P < 0.01) after 12 Gy (60)Co gamma ray radiation. Nevertheless, the cell morphology was obviously improved and the proliferation was enhanced by the addition of VEGF after 12 Gy radiation. HOXB2 gene played important roles in the biological activities of HUVECs. Small dose (6 Gy) gamma-radiation could promote, but large dose (12 Gy) could decrease the mRNA expression of HOXB2 gene in HUVECs. In addition, VEGF could protect HUVECs against radiation injury.

Anaplastic lymphoma kinase (ALK) gene rearrangements in radiation-related human papillary thyroid carcinoma after the Chernobyl accident.

PubMed

Arndt, Annette; Steinestel, Konrad; Rump, Alexis; Sroya, Manveer; Bogdanova, Tetiana; Kovgan, Leonila; Port, Matthias; Abend, Michael; Eder, Stefan

2018-04-06

Childhood radiation exposure has been associated with increased papillary thyroid carcinoma (PTC) risk. The role of anaplastic lymphoma kinase (ALK) gene rearrangements in radiation-related PTC remains unclear, but STRN-ALK fusions have recently been detected in PTCs from radiation exposed persons after Chernobyl using targeted next-generation sequencing and RNA-seq. We investigated ALK and RET gene rearrangements as well as known driver point mutations in PTC tumours from 77 radiation-exposed patients (mean age at surgery 22.4 years) and PTC tumours from 19 non-exposed individuals after the Chernobyl accident. ALK rearrangements were detected by fluorescence in situ hybridisation (FISH) and confirmed with immunohistochemistry (IHC); point mutations in the BRAF and RAS genes were detected by DNA pyrosequencing. Among the 77 tumours from exposed persons, we identified 7 ALK rearrangements and none in the unexposed group. When combining ALK and RET rearrangements, we found 24 in the exposed (31.2%) compared to two (10.5%) in the unexposed group. Odds ratios increased significantly in a dose-dependent manner up to 6.2 (95%CI: 1.1, 34.7; p = 0.039) at Iodine-131 thyroid doses >500 mGy. In total, 27 cases carried point mutations of BRAF or RAS genes, yet logistic regression analysis failed to identify significant dose association. To our knowledge we are the first to describe ALK rearrangements in post-Chernobyl PTC samples using routine methods such as FISH and IHC. Our findings further support the hypothesis that gene rearrangements, but not oncogenic driver mutations, are associated with ionizing radiation-related tumour risk. IHC may represent an effective method for ALK-screening in PTCs with known radiation aetiology, which is of clinical value since oncogenic ALK activation might represent a valuable target for small molecule inhibitors. © 2018 The Authors The Journal of Pathology: Clinical Research published by The Pathological Society of Great Britain and Ireland and John Wiley & Sons Ltd.

[Efficacy of HSV-tk/GCV system on human laryngeal squamous cell cancer in vitro].

PubMed

Ding, Xiu-yong; Qin, Yong; Li, Fu-ying; Cong, Tie-chuan

2006-05-01

Efficacy of HSV-tk/GCV system antitumor effects was assessed on human laryngeal cancer cell line Hep-2 in vitro. To assess the HSV-tk/CGV system whether has an antitumour effect on human laryngeal squamous cell cancer Hep-2 in vitro. The mechanisms of cytotoxity were also assessed. Hep-2 cells were transfected with HSV-tk gene by lipofection. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the HSV-tk gene expression. MTT was utilized to test for the cytotoxicity of this system. The cell-circle arrest and apoptosis were analyzed by flowcytometry assay. HSV-tk gene transfected cells demonstrated obvious cytoreductivity followed by ganciclovir (GCV) administration and this cytoreductivity showed partial GCV dose-independent. HSV-tk gene transfected cells demonstrated obvious s-phase arrest, no apoptosis and necrosis occurred. The HSV-tk/GCV system can inhabit the growth of Hep-2 cells effectively. S-phase arrest perhaps is the main reason that leads to the cell inhibition in our study. HSV-tk/GCV system has potential antitumor effects for the future clinical practice.

Oxidative Stress and Skeletal Health with Low-Dose, Low-LET (Linear Energy Transfer) Ionizing Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Globus, Ruth K.

We performed in vivo and in vitro experiments to accomplish the following specific aims of this project: 1) determine if low dose, low LET radiation affects skeletal remodeling at structural, cellular and molecular levels and 2) determine if low dose, low LET radiation modulates skeletal health during aging via oxidative mechanisms. A third aim is supported by NASA supplement to this DOE grant focusing on the influence of high LET radiation on bone. A series of experiments were conducted at the NASA Space Radiation Laboratory at Brookhaven, NSRL-BNL, using iron (56Fe) or a sequential exposure to protons / iron /more » protons, and separate experiments at NASA Ames Research Center (ARC) using 137Cs. The following provides a summary of key findings. (1) Exposure of nine-week old female mice to priming doses of gamma radiation (10cGy x 5) did not significantly affect bone volume/total volume (BV/TV) or microarchitecture as analyzed by 3D microcomputed tomography. As expected, exposure to the challenge dose of 2 Gy gamma irradiation resulted in significant decreases in BV/TV. The priming dose combined with the 2Gy challenge dose had no further effect on BV/TV compared to challenge dose alone, with the sole exception of the Structural Model Index (SMI). SMI reflects the ratio of rods-to-plates in cancellous bone tissue, such that higher SMI values indicate a tendency toward a weaker structure compared to lower SMI values. Mice treated with both priming and challenge dose had 25% higher SMI values compared to sham-irradiated controls and 7% higher values compared to mice treated with the challenge dose alone. Thus, although this priming regimen had relatively modest effects on cancellous tissue, the difference in SMI suggests this fractionated priming doses have adverse, rather than beneficial, effects on bone structure. (2) In 10-week old male mice, a single exposure to 100cGy of 137Cs reduces trabecular bone number and connectivity density by 20% and 36% respectively one month after irradiation (IR). At four months post-IR, these animals were comparable to sham-treated controls with regards to the abovementioned structural parameters. Irradation at 1 or 10 cGy did not result in any significant changes in bone structural parameters. (3) Irradiation of 16-wk old male mice with high doses of 56Fe or proton (50 or 200cGy), but not at low doses (5 or 10cGy), showed a similar loss of cancellous BV/TV and trabecular number at five weeks post-IR. (4) Age-related bone loss overtook acute radiation-induced decrements in bone structure within four months post-IR with 100 cGy gamma and 12 months post-IR with 200 cGy iron. Transgenic mice globally overexpressing human catalase gene in mitochondria did not exhibit cancellous bone loss as assessed at four month post-IR with 10 cGy proton, 50 cGy iron, or in combination. (5) The cellular and molecular mechanisms responsible for loss of bone with radiation are mediated primarily through increased osteoclastogenesis. Our data provide evidence that there are increases in gene expression of TNF alpha and MCP1 in the bone marrow cells 24 hours post-IR and of osteoclastogenic differentiation factor RANKL by day 3. These cytokines in the marrow may stimulate mature osteoclasts or drive osteoclastogenesis from precursors. (6) Osteoblastogenesis from marrow progenitors evaluated ex vivo decreased following whole body 56Fe irradiation at a dose threshold between 20 and 50 cGy whereas osteoclastogenesis ex vivo increased with doses as low as 10cGy two days post-IR of mice. However, the latter finding was not observed in more than a single experiment. (7) Gamma irradiation of cells in vitro requires relatively high doses (200cGy) to disturb normal osteoblastogenesis and osteoclastogenesis as evidenced by decrements in mineralized nodule formation, osteoclast counts, and expression of osteoblast related genes such as runx2, col1a1. (8) We also investigated the effect of antioxidants on osteoblastogenesis following low dose in vitro gamma irradiation (15cGy) on day four bone marrow stromal cell cultures. Superoxide dismutase (SOD) was added to the cell culture medium for 2 or 3 days post-irradiation and cell colonies were counted on days 7 and 10. SOD treatment increased cell growth as measured by DNA content and colony forming units (CFU) in both irradiated cells and 0 cGy control groups. However, low dose radiation of 15cGy abolished SOD stimulatory effects on cell growth and CFU number. These results suggest that exogenous SOD increases osteoblast cell growth and colony formation and that low-dose radiation (15cGy) can interfere with the antioxidant effects. In summary, our findings indicate that acute, whole body irradiation at high doses (50-200 cGy) results in prompt tissue degradation and bone loss. Lower doses (<50 cGy) do not cause bone structural deterioration but may deplete stem/progenitor cell pools in the bone marrow.« less

Preharvest Ultraviolet C Irradiation Increased the Level of Polyphenol Accumulation and Flavonoid Pathway Gene Expression in Strawberry Fruit.

PubMed

Xu, Yanqun; Charles, Marie Thérèse; Luo, Zisheng; Mimee, Benjamin; Veronneau, Pierre-Yves; Rolland, Daniel; Roussel, Dominique

2017-11-22

Preharvest ultraviolet C (UV-C) irradiation is an innovative approach for increasing the bioactive phytochemical content of strawberries to increase the disease resistance and nutritional value. This study investigated the changes in individual flavonoids in strawberry developed with three different cumulative doses of preharvest UV-C treatment (low, 9.6 kJ m -2 ; middle, 15 kJ m -2 ; and high , 29.4 kJ m -2 ). Significant accumulation (p < 0.05) of phenolics (25-75% increase), namely, cyanidin 3-glucoside, pelargonidin 3-glucoside/rutinoside, glucoside and glucuronide of quercetin and kaempferol, and ellagic acid, was found in the fruit subjected to low and middle supplemental doses of UV-C radiation. The expression of the flavonoid pathway structural genes, i.e., FaCHS1, FaCHI, FaFHT, FaDFR, FaFLS, and FaFGT, was upregulated in the low- and middle-dose groups, while the early stage genes were not affected by the high dose. FaMYB1 was also relatively enhanced in the low- and middle-dose groups, while FaASR was upregulated in only the low-dose group. Hormetic preharvest UV-C dose ranges for enhancing the polyphenol content of strawberries were established for the first time.

A single dose of lysergic acid diethylamide influences gene expression patterns within the mammalian brain.

PubMed

Nichols, Charles D; Sanders-Bush, Elaine

2002-05-01

Hallucinogenic drugs such as lysergic acid diethylamide (LSD) have profound effects on humans including hallucinations and detachment from reality. These remarkable behavioral effects have many similarities to the debilitating symptoms of neuropsychiatric disorders such as schizophrenia. The effects of hallucinogens are thought to be mediated by serotonin receptor activation; however, how these drugs elicit the unusual behavioral effects remains largely a mystery, despite much research. We have undertaken the first comprehensive analysis of gene expression influenced by acute LSD administration in the mammalian brain. These studies represent a novel approach to elucidate the mechanism of action of this class of drugs. We have identified a number of genes that are predicted to be involved in the processes of synaptic plasticity, glutamatergic signaling and cytoskeletal architecture. Understanding these molecular events will lead to new insights into the etiology of disorders whose behavioral symptoms resemble the temporary effects of hallucinogenic drugs, and also may ultimately result in new therapies.

Long-term safety and efficacy of AAV gene therapy in the canine model of glycogen storage disease type Ia.

PubMed

Lee, Young Mok; Conlon, Thomas J; Specht, Andrew; Coleman, Kirsten E; Brown, Laurie M; Estrella, Ana M; Dambska, Monika; Dahlberg, Kathryn R; Weinstein, David A

2018-05-25

Viral mediated gene therapy has progressed after overcoming early failures, and gene therapy has now been approved for several conditions in Europe and the USA. Glycogen storage disease (GSD) type Ia, caused by a deficiency of glucose-6-phosphatase-α, has been viewed as an outstanding candidate for gene therapy. This follow-up report describes the long-term outcome for the naturally occurring GSD-Ia dogs treated with rAAV-GPE-hG6PC-mediated gene therapy. A total of seven dogs were treated with rAAV-GPE-hG6PC-mediated gene therapy. The first four dogs were treated at birth, and three dogs were treated between 2 and 6 months of age to assess the efficacy and safety in animals with mature livers. Blood and urine samples, radiographic studies, histological evaluation, and biodistribution were assessed. Gene therapy improved survival in the GSD-Ia dogs. With treatment, the biochemical studies normalized for the duration of the study (up to 7 years). None of the rAAV-GPE-hG6PC-treated dogs had focal hepatic lesions or renal abnormalities. Dogs treated at birth required a second dose of rAAV after 2-4 months; gene therapy after hepatic maturation resulted in improved efficacy after a single dose. rAAV-GPE-hG6PC treatment in GSD-Ia dogs was found to be safe and efficacious. GSD-Ia is an attractive target for human gene therapy since it is a monogenic disorder with limited tissue involvement. Blood glucose and lactate monitoring can be used to assess effectiveness and as a biomarker of success. GSD-Ia can also serve as a model for other hepatic monogenic disorders.

Effect of a thymol application on olfactory memory and gene expression levels in the brain of the honeybee Apis mellifera.

PubMed

Bonnafé, Elsa; Drouard, Florian; Hotier, Lucie; Carayon, Jean-Luc; Marty, Pierre; Treilhou, Michel; Armengaud, Catherine

2015-06-01

Essential oils are used by beekeepers to control the Varroa mites that infest honeybee colonies. So, bees can be exposed to thymol formulations in the hive. The effects of the monoterpenoid thymol were explored on olfactory memory and gene expression in the brain of the honeybee. In bees previously exposed to thymol (10 or 100 ng/bee), the specificity of the response to the conditioned stimulus (CS) was lost 24 h after learning. Besides, the octopamine receptor OA1 gene Amoa1 showed a significant decrease of expression 3 h after exposure with 10 or 100 ng/bee of thymol. With the same doses, expression of Rdl gene, coding for a GABA receptor subunit, was not significantly modified but the trpl gene was upregulated 1 and 24 h after exposure to thymol. These data indicated that the genes coding for the cellular targets of thymol could be rapidly regulated after exposure to this molecule. Memory and sensory processes should be investigated in bees after chronic exposure in the hive to thymol-based preparations.

Aquatic contaminants alter genes involved in neurotransmitter synthesis and gonadotropin release in largemouth bass.

PubMed

Martyniuk, Christopher J; Sanchez, Brian C; Szabo, Nancy J; Denslow, Nancy D; Sepúlveda, Maria S

2009-10-19

Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens (microg/g): atrazine (0.3 and 3.0), toxaphene (10 and 100), cadmium (CdCl(2)) (0.000067 and 0.00067), polychlorinated biphenyl (PCB) 126 (0.25 and 2.5), and phenanthrene (5 and 50). Partial largemouth bass gene segments were cloned for enzymes involved in neurotransmitter (glutamic acid decarboxylase 65, GAD65; tyrosine hydroxylase) and estrogen (brain aromatase; CYP19b) synthesis for real-time PCR assays. In addition, neuropeptides regulating feeding (neuropeptide Y) and reproduction (chicken GnRH-II, cGnRH-II; salmon GnRH, sGnRH) were also investigated. Of the chemicals tested, only cadmium, PCB 126, and phenanthrene showed any significant effects on the genes tested, while atrazine and toxaphene did not. Cadmium (0.000067 microg/g) significantly increased cGnRH-II mRNA while PCB 126 (0.25 microg/g) decreased GAD65 mRNA. Phenanthrene decreased GAD65 and tyrosine hydroxylase mRNA levels at the highest dose (50 microg/g) but increased cGnRH-II mRNA at the lowest dose (5 microg/g). CYP19b, NPY, and sGnRH mRNA levels were unaffected by any of the treatments. A hierarchical clustering dendrogram grouped PCB 126 and phenanthrene more closely than other chemicals with respect to the genes tested. This study demonstrates that brain transcripts important for neurotransmitter synthesis neuroendocrine function are potential targets for emerging and prevalent aquatic contaminants.

Plasmodium falciparum malaria skews globin gene expression balance in in-vitro haematopoietic stem cell culture system: Its implications in malaria associated anemia.

PubMed

Pathak, Vrushali; Colah, Roshan; Ghosh, Kanjaksha

2018-02-01

Understanding the pathophysiology and associated host parasite interactions of the malaria infection is the prerequisite for developing effective prevention and treatment strategies. The exact mechanism underlying malaria associated ineffective and dyserythropoiesis is not yet fully understood. Being an important protein, haemoglobin serves as the main amino acid reservoir available to the intra-erythrocytic plasmodium. It is important to check the expression profiling of globin genes which may help us to understand host parasite interactions and its potential contribution to both infection and disease. Here, an in-vitro culture system was used to study the effect of different doses of Plasmodium falciparum on haematopoietic stem cell expansion, differentiation and expression of globin genes. Upon exposure to the different doses of P. falciparum parasites of strains 3D7, Dd2 and RKL9 (intact and lysed form) at different stages of erythroid development, cells demonstrated suppression in growth and differentiation. At almost all stages of erythroid development upon parasite exposure, the γ globin gene was found to be downregulated and the α/β as well as α/non- α globin mRNA ratios in late stage erythroid cells were found to be reduced (p < .01) compared to the untreated controls. The imbalance in globin chain expression might be considered as one of the factors involved in malaria associated inappropriate erythropoietic responses. Copyright © 2018 Elsevier Inc. All rights reserved.

Non-Thermal Plasma Treatment Diminishes Fungal Viability and Up-Regulates Resistance Genes in a Plant Host

PubMed Central

Panngom, Kamonporn; Lee, Sang Hark; Park, Dae Hoon; Sim, Geon Bo; Kim, Yong Hee; Uhm, Han Sup; Park, Gyungsoon; Choi, Eun Ha

2014-01-01

Reactive oxygen and nitrogen species can have either harmful or beneficial effects on biological systems depending on the dose administered and the species of organism exposed, suggesting that application of reactive species can possibly produce contradictory effects in disease control, pathogen inactivation and activation of host resistance. A novel technology known as atmospheric-pressure non-thermal plasma represents a means of generating various reactive species that adversely affect pathogens (inactivation) while simultaneously up-regulating host defense genes. The anti-microbial efficacy of this technology was tested on the plant fungal pathogen Fusarium oxysporum f.sp. lycopersici and its susceptible host plant species Solanum lycopercicum. Germination of fungal spores suspended in saline was decreased over time after exposed to argon (Ar) plasma for 10 min. Although the majority of treated spores exhibited necrotic death, apoptosis was also observed along with the up-regulation of apoptosis related genes. Increases in the levels of peroxynitrite and nitrite in saline following plasma treatment may have been responsible for the observed spore death. In addition, increased transcription of pathogenesis related (PR) genes was observed in the roots of the susceptible tomato cultivar (S. lycopercicum) after exposure to the same Ar plasma dose used in fungal inactivation. These data suggest that atmospheric-pressure non-thermal plasma can be efficiently used to control plant fungal diseases by inactivating fungal pathogens and up-regulating mechanisms of host resistance. PMID:24911947

Novel redox nanomedicine improves gene expression of polyion complex vector

NASA Astrophysics Data System (ADS)

Toh, Kazuko; Yoshitomi, Toru; Ikeda, Yutaka; Nagasaki, Yukio

2011-12-01

Gene therapy has generated worldwide attention as a new medical technology. While non-viral gene vectors are promising candidates as gene carriers, they have several issues such as toxicity and low transfection efficiency. We have hypothesized that the generation of reactive oxygen species (ROS) affects gene expression in polyplex supported gene delivery systems. The effect of ROS on the gene expression of polyplex was evaluated using a nitroxide radical-containing nanoparticle (RNP) as an ROS scavenger. When polyethyleneimine (PEI)/pGL3 or PEI alone was added to the HeLa cells, ROS levels increased significantly. In contrast, when (PEI)/pGL3 or PEI was added with RNP, the ROS levels were suppressed. The luciferase expression was increased by the treatment with RNP in a dose-dependent manner and the cellular uptake of pDNA was also increased. Inflammatory cytokines play an important role in ROS generation in vivo. In particular, tumor necrosis factor (TNF)-α caused intracellular ROS generation in HeLa cells and decreased gene expression. RNP treatment suppressed ROS production even in the presence of TNF-α and increased gene expression. This anti-inflammatory property of RNP suggests that it may be used as an effective adjuvant for non-viral gene delivery systems.

Allium sativum L. regulates in vitro IL-17 gene expression in human peripheral blood mononuclear cells.

PubMed

Moutia, Mouna; Seghrouchni, Fouad; Abouelazz, Omar; Elouaddari, Anass; Al Jahid, Abdellah; Elhou, Abdelhalim; Nadifi, Sellama; Jamal Eddine, Jamal; Habti, Norddine; Badou, Abdallah

2016-09-29

Allium sativum L. (A.S.) "garlic", one of the most interesting medicinal plants, has been suggested to contain compounds that could be beneficial in numerous pathological situations including cancer. In this work, we aimed to assess the immunomodulatory effect of A.S. preparation on human peripheral blood mononuclear cells from healthy individuals. Nontoxic doses of A.S. were identified using MTT assay. Effects on CD4+ or CD8+ T lymphocyte proliferation were studied using flow cytometry. The effect of A.S. on cytokine gene expression was studied using qRT-PCR. Finally, qualitative analysis of A.S. was performed by HPLC approach. Data were analyzed statistically by one-way ANOVA test. The nontoxic doses of A.S. preparation did not affect neither spontaneous nor TCR-mediated CD4+ or CD8+ T lymphocyte proliferation. Interestingly, A.S. exhibited a statistically significant regulation of IL-17 gene expression, a cytokine involved in several inflammatory and autoimmune diseases. In contrast, the expression of IL-4, an anti-inflammatory cytokine, was unaffected. Qualitative analysis of A.S. ethanol preparation indicated the presence of three polyphenol bioactive compounds, which are catechin, vanillic acid and ferulic acid. The specific inhibition of the pro-inflammatory cytokine, IL-17 without affecting cell proliferation in human PBMCs by the Allium sativum L. preparation suggests a potential valuable effect of the compounds present in this plant for the treatment of inflammatory diseases and cancer, where IL-17 is highly expressed. The individual contribution of these three compounds to this global effect will be assessed.

Immunostimulatory AdCD40L gene therapy combined with low-dose cyclophosphamide in metastatic melanoma patients

PubMed Central

Loskog, Angelica; Maleka, Aglaia; Mangsbo, Sara; Svensson, Emma; Lundberg, Christina; Nilsson, Anders; Krause, Johan; Agnarsdóttir, Margrét; Sundin, Anders; Ahlström, Håkan; Tötterman, Thomas H; Ullenhag, Gustav

2016-01-01

Background: Current approaches for treating metastatic malignant melanoma (MM) are not effective enough and are associated with serious adverse events. Due to its immunogenicity, melanoma is an attractive target for immunostimulating therapy. In this phase I/IIa study, local AdCD40L immunostimulatory gene therapy was evaluated in patients with MM. Methods: AdCD40L is an adenovirus carrying the gene for CD40 ligand. Patients that failed standard treatments were enrolled. Six patients received four weekly intratumoral AdCD40L injections. Next, nine patients received low-dose cyclophosphamide conditioning before the first and fourth AdCD40L injection. The blood samples were collected at multiple time points for chemistry, haematology and immunology evaluations. Radiology was performed at enrolment and repeated twice after the treatment. Results: AdCD40L was safe with mild transient reactions. No objective responses were recorded by MRI, however, local and distant responses were seen on FDG-PET. The overall survival at 6 months was significantly better when cyclophosphamide was added to AdCD40L. The patients with the best survival developed the highest levels of activated T cells and experienced a pronounced decrease of intratumoral IL8. Conclusions: AdCD40L therapy for MM was well tolerated. Local and distant responses along with better survival in the low-dose cyclophosphamide group are encouraging. PMID:27031851

AAV5-Factor VIII Gene Transfer in Severe Hemophilia A.

PubMed

Rangarajan, Savita; Walsh, Liron; Lester, Will; Perry, David; Madan, Bella; Laffan, Michael; Yu, Hua; Vettermann, Christian; Pierce, Glenn F; Wong, Wing Y; Pasi, K John

2017-12-28

Patients with hemophilia A rely on exogenous factor VIII to prevent bleeding in joints, soft tissue, and the central nervous system. Although successful gene transfer has been reported in patients with hemophilia B, the large size of the factor VIII coding region has precluded improved outcomes with gene therapy in patients with hemophilia A. We infused a single intravenous dose of a codon-optimized adeno-associated virus serotype 5 (AAV5) vector encoding a B-domain-deleted human factor VIII (AAV5-hFVIII-SQ) in nine men with severe hemophilia A. Participants were enrolled sequentially into one of three dose cohorts (low dose [one participant], intermediate dose [one participant], and high dose [seven participants]) and were followed through 52 weeks. Factor VIII activity levels remained at 3 IU or less per deciliter in the recipients of the low or intermediate dose. In the high-dose cohort, the factor VIII activity level was more than 5 IU per deciliter between weeks 2 and 9 after gene transfer in all seven participants, and the level in six participants increased to a normal value (>50 IU per deciliter) that was maintained at 1 year after receipt of the dose. In the high-dose cohort, the median annualized bleeding rate among participants who had previously received prophylactic therapy decreased from 16 events before the study to 1 event after gene transfer, and factor VIII use for participant-reported bleeding ceased in all the participants in this cohort by week 22. The primary adverse event was an elevation in the serum alanine aminotransferase level to 1.5 times the upper limit of the normal range or less. Progression of preexisting chronic arthropathy in one participant was the only serious adverse event. No neutralizing antibodies to factor VIII were detected. The infusion of AAV5-hFVIII-SQ was associated with the sustained normalization of factor VIII activity level over a period of 1 year in six of seven participants who received a high dose, with stabilization of hemostasis and a profound reduction in factor VIII use in all seven participants. In this small study, no safety events were noted, but no safety conclusions can be drawn. (Funded by BioMarin Pharmaceutical; ClinicalTrials.gov number, NCT02576795 ; EudraCT number, 2014-003880-38 .).

Progress in Assessing Air Pollutant Risks from In Vitro Exposures: Matching Ozone Dose and Effect in Human Airway Cells

PubMed Central

Hatch, Gary E.; Duncan, Kelly E.; Diaz-Sanchez, David; Schmitt, Michael T.; Ghio, Andrew J.; Carraway, Martha Sue; McKee, John; Dailey, Lisa A.; Berntsen, Jon; Devlin, Robert B.

2014-01-01

In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in vivo exposure of a living person. The goal of the present study was to compare the dose and effect of O3 in airway cells of humans exposed in vivo to that of human cells exposed in vitro. Ten subjects breathed labeled O3 (18O3, 0.3 ppm, 2 h) while exercising intermittently. Bronchial brush biopsies and lung lavage fluids were collected 1 h post exposure for in vivo data whereas in vitro data were obtained from primary cultures of human bronchial epithelial cells exposed to 0.25–1.0 ppm 18O3 for 2 h. The O3 dose to the cells was defined as the level of 18O incorporation and the O3 effect as the fold increase in expression of inflammatory marker genes (IL-8 and COX-2). Dose and effect in cells removed from in vivo exposed subjects were lower than in cells exposed to the same 18O3 concentration in vitro suggesting upper airway O3 scrubbing in vivo. Cells collected by lavage as well as previous studies in monkeys show that cells deeper in the lung receive a higher O3 dose than cells in the bronchus. We conclude that the methods used herein show promise for replicating and comparing the in vivo dose and effect of O3 in an in vitro system. PMID:24928893

Gamma camera dual imaging with a somatostatin receptor and thymidine kinase after gene transfer with a bicistronic adenovirus in mice.

PubMed

Zinn, Kurt R; Chaudhuri, Tandra R; Krasnykh, Victor N; Buchsbaum, Donald J; Belousova, Natalya; Grizzle, William E; Curiel, David T; Rogers, Buck E

2002-05-01

To compare two systems for assessing gene transfer to cancer cells and xenograft tumors with noninvasive gamma camera imaging. A replication-incompetent adenovirus encoding the human type 2 somatostatin receptor (hSSTr2) and the herpes simplex virus thymidine kinase (TK) enzyme (Ad-hSSTr2-TK) was constructed. A-427 human lung cancer cells were infected in vitro and mixed with uninfected cells at different ratios. A-427 tumors in nude mice (n = 23) were injected with 1 x 10(6) to 5 x 10(8) plaque-forming units (pfu) of Ad-hSSTr2-TK. The expressed hSSTr2 and TK proteins were imaged owing to internally bound, or trapped, technetium 99m ((99m)Tc)-labeled hSSTr2-binding peptide (P2045) and radioiodinated 2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl-5-iodouracil (FIAU), respectively. Iodine 125 ((125)I)-labeled FIAU was used in vitro and iodine 131 ((131)I)-labeled FIAU, in vivo. The (99m)Tc-labeled P2045 and (125)I- or (131)I-labeled FIAU were imaged simultaneously with different window settings with an Anger gamma camera. Treatment effects were tested with analysis of variance. Infected cells in culture trapped (125)I-labeled FIAU and (99m)Tc-labeled P2045; uptake correlated with the percentage of Ad-hSSTr2-TK-positive cells. For 100% of infected cells, 24% +/- 0.4 (mean +/- SD) of the added (99m)Tc-labeled P2045 was trapped, which is significantly lower (P <.05) than the 40% +/- 2 of (125)I-labeled FIAU that was trapped. For the highest Ad-hSSTr2-TK tumor dose (5 x 10(8) pfu), the uptake of (99m)Tc-labeled P2045 was 11.1% +/- 2.9 of injected dose per gram of tumor (thereafter, dose per gram), significantly higher (P <.05) than the uptake of (131)I-labeled FIAU at 1.6% +/- 0.4 dose per gram. (99m)Tc-labeled P2045 imaging consistently depicted hSSTr2 gene transfer in tumors at all adenovirus doses. Tumor uptake of (99m)Tc-labeled P2045 positively correlated with Ad-hSSTr2-TK dose; (131)I-labeled FIAU tumor uptake did not correlate with vector dose. The hSSTr2 and TK proteins were simultaneously imaged following dual gene transfer with an adenovirus vector. Copyright RSNA, 2002

Dose and Time Dependencies in Stress Pathway Responses during Chemical Exposure: Novel Insights from Gene Regulatory Networks.

PubMed

Souza, Terezinha M; Kleinjans, Jos C S; Jennen, Danyel G J

2017-01-01

Perturbation of biological networks is often observed during exposure to xenobiotics, and the identification of disturbed processes, their dynamic traits, and dose-response relationships are some of the current challenges for elucidating the mechanisms determining adverse outcomes. In this scenario, reverse engineering of gene regulatory networks (GRNs) from expression data may provide a system-level snapshot embedded within accurate molecular events. Here, we investigate the composition of GRNs inferred from groups of chemicals with two distinct outcomes, namely carcinogenicity [azathioprine (AZA) and cyclophosphamide (CYC)] and drug-induced liver injury (DILI; diclofenac, nitrofurantoin, and propylthiouracil), and a non-carcinogenic/non-DILI group (aspirin, diazepam, and omeprazole). For this, we analyzed publicly available exposed in vitro human data, taking into account dose and time dependencies. Dose-Time Network Identification (DTNI) was applied to gene sets from exposed primary human hepatocytes using four stress pathways, namely endoplasmic reticulum (ER), NF-κB, NRF2, and TP53. Inferred GRNs suggested case specificity, varying in interactions, starting nodes, and target genes across groups. DILI and carcinogenic compounds were shown to directly affect all pathway-based GRNs, while non-DILI/non-carcinogenic chemicals only affected NF-κB. NF-κB-based GRNs clearly illustrated group-specific disturbances, with the cancer-related casein kinase CSNK2A1 being a target gene only in the carcinogenic group, and opposite regulation of NF-κB subunits being observed in DILI and non-DILI/non-carcinogenic groups. Target genes in NRF2-based GRNs shared by DILI and carcinogenic compounds suggested markers of hepatotoxicity. Finally, we indicate several of these group-specific interactions as potentially novel. In summary, our reversed-engineered GRNs are capable of revealing dose dependent, chemical-specific mechanisms of action in stress-related biological networks.

Editor's Highlight: Application of Gene Set Enrichment Analysis for Identification of Chemically Induced, Biologically Relevant Transcriptomic Networks and Potential Utilization in Human Health Risk Assessment.

PubMed

Dean, Jeffry L; Zhao, Q Jay; Lambert, Jason C; Hawkins, Belinda S; Thomas, Russell S; Wesselkamper, Scott C

2017-05-01

The rate of new chemical development in commerce combined with a paucity of toxicity data for legacy chemicals presents a unique challenge for human health risk assessment. There is a clear need to develop new technologies and incorporate novel data streams to more efficiently inform derivation of toxicity values. One avenue of exploitation lies in the field of transcriptomics and the application of gene expression analysis to characterize biological responses to chemical exposures. In this context, gene set enrichment analysis (GSEA) was employed to evaluate tissue-specific, dose-response gene expression data generated following exposure to multiple chemicals for various durations. Patterns of transcriptional enrichment were evident across time and with increasing dose, and coordinated enrichment plausibly linked to the etiology of the biological responses was observed. GSEA was able to capture both transient and sustained transcriptional enrichment events facilitating differentiation between adaptive versus longer term molecular responses. When combined with benchmark dose (BMD) modeling of gene expression data from key drivers of biological enrichment, GSEA facilitated characterization of dose ranges required for enrichment of biologically relevant molecular signaling pathways, and promoted comparison of the activation dose ranges required for individual pathways. Median transcriptional BMD values were calculated for the most sensitive enriched pathway as well as the overall median BMD value for key gene members of significantly enriched pathways, and both were observed to be good estimates of the most sensitive apical endpoint BMD value. Together, these efforts support the application of GSEA to qualitative and quantitative human health risk assessment. Published by Oxford University Press on behalf of the Society of Toxicology 2017. This work is written by US Government employees and is in the public domain in the US.

Dose response evaluation of gene expression profiles in the skin of K6/ODC mice exposed to sodium arsenite.

PubMed

Ahlborn, Gene J; Nelson, Gail M; Ward, William O; Knapp, Geremy; Allen, James W; Ouyang, Ming; Roop, Barbara C; Chen, Yan; O'Brien, Thomas; Kitchin, Kirk T; Delker, Don A

2008-03-15

Chronic drinking water exposure to inorganic arsenic and its metabolites increases tumor frequency in the skin of K6/ODC transgenic mice. To identify potential biomarkers and modes of action for this skin tumorigenicity, we characterized gene expression profiles from analysis of K6/ODC mice administered 0, 0.05, 0.25, 1.0 and 10 ppm sodium arsenite in their drinking water for 4 weeks. Following exposure, total RNA was isolated from mouse skin and processed to biotin-labeled cRNA for microarray analyses. Skin gene expression was analyzed with Affymetrix Mouse Genome 430A 2.0 GeneChips, and pathway analysis was conducted with DAVID (NIH), Ingenuity Systems and MetaCore's GeneGo. Differential expression of several key genes was verified through qPCR. Only the highest dose (10 ppm) resulted in significantly altered KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including MAPK, regulation of actin cytoskeleton, Wnt, Jak-Stat, Tight junction, Toll-like, phosphatidylinositol and insulin signaling pathways. Approximately 20 genes exhibited a dose response, including several genes known to be associated with carcinogenesis or tumor progression including cyclin D1, CLIC4, Ephrin A1, STAT3 and DNA methyltransferase 3a. Although transcription changes in all identified genes have not previously been linked to arsenic carcinogenesis, their association with carcinogenesis in other systems suggests that these genes may play a role in the early stages of arsenic-induced skin carcinogenesis and can be considered potential biomarkers.

Dose response relationship in anti-stress gene regulatory networks.

PubMed

Zhang, Qiang; Andersen, Melvin E

2007-03-02

To maintain a stable intracellular environment, cells utilize complex and specialized defense systems against a variety of external perturbations, such as electrophilic stress, heat shock, and hypoxia, etc. Irrespective of the type of stress, many adaptive mechanisms contributing to cellular homeostasis appear to operate through gene regulatory networks that are organized into negative feedback loops. In general, the degree of deviation of the controlled variables, such as electrophiles, misfolded proteins, and O2, is first detected by specialized sensor molecules, then the signal is transduced to specific transcription factors. Transcription factors can regulate the expression of a suite of anti-stress genes, many of which encode enzymes functioning to counteract the perturbed variables. The objective of this study was to explore, using control theory and computational approaches, the theoretical basis that underlies the steady-state dose response relationship between cellular stressors and intracellular biochemical species (controlled variables, transcription factors, and gene products) in these gene regulatory networks. Our work indicated that the shape of dose response curves (linear, superlinear, or sublinear) depends on changes in the specific values of local response coefficients (gains) distributed in the feedback loop. Multimerization of anti-stress enzymes and transcription factors into homodimers, homotrimers, or even higher-order multimers, play a significant role in maintaining robust homeostasis. Moreover, our simulation noted that dose response curves for the controlled variables can transition sequentially through four distinct phases as stressor level increases: initial superlinear with lesser control, superlinear more highly controlled, linear uncontrolled, and sublinear catastrophic. Each phase relies on specific gain-changing events that come into play as stressor level increases. The low-dose region is intrinsically nonlinear, and depending on the level of local gains, presence of gain-changing events, and degree of feedforward gene activation, this region can appear as superlinear, sublinear, or even J-shaped. The general dose response transition proposed here was further examined in a complex anti-electrophilic stress pathway, which involves multiple genes, enzymes, and metabolic reactions. This work would help biologists and especially toxicologists to better assess and predict the cellular impact brought about by biological stressors.

PTH (1-34) affects bone turnover governed by osteocytes exposed to fluoride.

PubMed

Yu, Xiuhua; Yu, Haolan; Jiang, Ningning; Zhang, Xiuyun; Zhang, Mengmeng; Xu, Hui

2018-05-15

Exposure to fluoride from environmental sources remains an overlooked, but serious public health risk. In this study, we looked into the role osteocytes play on the mechanism underlying fluoride induced osteopathology. We analyzed bone formation and resorption related genes generated by osteocytes that were exposed to varied doses of fluoride with and without PTH in vitro. Correspondingly, osteogenesis and osteoclastogenesis related genes were also investigated in rats exposed to fluoride for 8 weeks, and the PTH(1-34)was applied at the last 3 weeks to observe its role in regulating bone turnover upon fluoride treatment. The data in vitro indicated that fluoride treatment inhibited Sost expression of mRNA and protein and stimulated RANKL mRNA protein expression as well as the RANKL/OPG ratio in the primary osteocytes. Single PTH treatment played the similar role on expression of these genes and proteins. The PTH combined administration enhanced the action of fluoride treatment on RNAKL/OPG and SOST/Sclerostin. The up-regulation of RANKL and decreasing of Sost induced by fluoride and/or PTH treatment was validated in vivo and suggests that osteocytes are a major source of RANKL and Sost, both of which play essential roles in fluoride affecting osteogenesis and osteoclastogenesis. Expression of Wnt/β-catenin was up-regulated in both in vitro osteocytes treated with high dose of fluoride and bone tissue of rats in the presence of fluoride and PTH. In vivo, fluoride and single PTH stimulated bone turnover respectively, furthermore, PTH combined with low dose of fluoride treatment reinforced the osteogenesis and osteoclastogenesis genes expression, however, co-treatment of PTH reversed the effect of high dose of fluoride on osteogenesis and osteoclastogenensis related factors. In conclusion, this study demonstrated that osteocytes play a key role in fluoride activated bone turnover, and PTH participates in the process of fluoride modulating SOST/Sclerostin and RANKL expression. Copyright © 2018 Elsevier B.V. All rights reserved.

Chemoprevention by Quercetin of Oral Squamous Cell Carcinoma by Suppression of the NF-κB Signaling Pathway in DMBA-treated Hamsters.

PubMed

Zhang, Wen; Yin, Gang; Dai, Jianguo; Sun, Y U; Hoffman, Robert M; Yang, Zhijian; Fan, Yuan

2017-08-01

The aim of this study was to investigate the effects of the flavonoid quercetin on chemoprevention of oral squamous cell carcinoma (OSCC). The study involved molecular signaling pathways in 7,12-dimethylbenz(a) anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. DMBA (0.5%) was painted at the right buccal pouches of hamsters for 14 weeks to induce carcinoma. DMBA-treated hamsters received simultaneous doses of quercetin. Animals without DMBA induction were used as normal controls. The incidence of OSCC and the severity of pre-malignant lesions were determined histologically. Apoptosis in the pouch tissue was determined by TUNEL staining. The mRNA and protein expression of NF-κB p50 and p65, as well as Bcl-2 and Bax genes were analyzed using RT-PCR and Western blotting, respectively. Quercetin, at various doses, significantly reduced OSCC incidence and severity of hyperplasia and dysplasia compared to the DMBA-induction-only group (p<0.01). Apoptosis was induced by quercetin treatment compared to the DMBA-induction-only group (p<0.01). mRNA and protein expression of NF-κB p50, p65 as well as Bcl-2 genes were significantly suppressed by quercetin at high doses compared to DMBA induction only (p<0.05). However, mRNA and protein expression of the Bax gene was increased by quercetin treatment at medium and high doses, compared to the DMBA-induction-only group (p<0.05). Quercetin significantly reduced body-weight loss compared to the DMBA-induction-only group (p<0.05). Quercetin reduced tumor incidence and induced apoptosis through modulation of NF-κB signaling and its target genes Bcl-2 and Bax in the DMBA-induced carcigenesis hamster model, suggesting the potential of quercetin as a candidate for OSCC chemoprevention. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Early transcriptional changes in cardiac mitochondria during chronic doxorubicin exposure and mitigation by dexrazoxane in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vijay, Vikrant; Moland, Carrie L.; Han, Tao

Identification of early biomarkers of cardiotoxicity could help initiate means to ameliorate the cardiotoxic actions of clinically useful drugs such as doxorubicin (DOX). Since DOX has been shown to target mitochondria, transcriptional levels of mitochondria-related genes were evaluated to identify early candidate biomarkers in hearts of male B6C3F{sub 1} mice given a weekly intravenous dose of 3 mg/kg DOX or saline (SAL) for 2, 3, 4, 6, or 8 weeks (6, 9, 12, 18, or 24 mg/kg cumulative DOX doses, respectively). Also, a group of mice was pretreated (intraperitoneally) with the cardio-protectant, dexrazoxane (DXZ; 60 mg/kg) 30 min before eachmore » weekly dose of DOX or SAL. At necropsy a week after the last dose, increased plasma concentrations of cardiac troponin T (cTnT) were detected at 18 and 24 mg/kg cumulative DOX doses, whereas myocardial alterations were observed only at the 24 mg/kg dose. Of 1019 genes interrogated, 185, 109, 140, 184, and 451 genes were differentially expressed at 6, 9, 12, 18, and 24 mg/kg cumulative DOX doses, respectively, compared to concurrent SAL-treated controls. Of these, expression of 61 genes associated with energy metabolism and apoptosis was significantly altered before and after occurrence of myocardial injury, suggesting these as early genomics markers of cardiotoxicity. Much of these DOX-induced transcriptional changes were attenuated by pretreatment of mice with DXZ. Also, DXZ treatment significantly reduced plasma cTnT concentration and completely ameliorated cardiac alterations induced by 24 mg/kg cumulative DOX. This information on early transcriptional changes during DOX treatment may be useful in designing cardioprotective strategies targeting mitochondria. - Highlights: • Altered mitochondria-related gene expression before heart injury by doxorubicin • Dexrazoxane mitigated doxorubicin-induced early expression changes in mitochondria. • Dexrazoxane completely ameliorated doxorubicin-induced pathology in mouse heart.« less

A polymorphism in the glucocorticoid receptor gene is associated with refractory hypotension in premature infants.

PubMed

Ogasawara, Kei; Sato, Maki; Hashimoto, Koichi; Imamura, Takashi; Go, Hayato; Hosoya, Mitsuaki

2018-06-01

Glucocorticoids play an important role in endocrine control. The association of glucocorticoid receptor (GR) gene polymorphisms with altered sensitivity to glucocorticoid therapy has been reported in adults. However, there are few such reports in infants. The present study analyzed the prevalence of four GR polymorphisms in preterm infants born before 30 weeks of gestation and determined the associations between these polymorphisms and clinical outcomes in the infants. Totally, 41 preterm infants born at two hospitals in Fukushima were retrospectively screened for the presence of four GR gene polymorphisms, using a TaqMan single-nucleotide polymorphism genotyping assay. The effect of GR gene polymorphisms on clinical outcomes during hospitalization was evaluated. The following primary clinical outcomes were assessed: refractory hypotension in the acute phase and/or severe bronchopulmonary dysplasia, maximum dopamine and dobutamine doses administered, and total hydrocortisone dose administered in the first 48 h of life. Multivariate analysis with logistic regression was used to assess the association between clinical factors and refractory hypotension. Of the four GR polymorphisms, only the BclI polymorphism was detected. The genotype distribution was as follows: C/C, 33; C/G, 8; and G/G, 0 infants. Significant differences were observed between the C/C and C/G genotypes with respect to the following variables: refractory hypotension (6% vs. 50%), dopamine dose [3.0 (2.0-4.0) vs. 4.8 (4.0-7.5) μg/kg/min], dobutamine dose [2.4 (0.0-3.6) vs. 4.0 (0-10.0) μg/kg/min], and total hydrocortisone dose administered in the first 48 h of life [2.0 (0-10.0) vs. 6.0 (0-12.0) mg/kg]. Multivariate analysis showed that the BclI genotype (C/C) was significantly less associated with refractory hypotension in the acute phase (odds ratio, 0.008; 95% confidence interval, 0.000-0.371; p = 0.013). The incidence of refractory hypotension in infants with the C/C genotype was initially expected to be higher than that in infants with the C/G genotype. However, the results of this study were rather different from what we originally expected. The suppressive effect of antenatal steroid use on the HPA axis of the preterm infants with the BclI variant may be associated with refractory hypotension in the acute phase. Copyright © 2017. Published by Elsevier B.V.

Toxic effects of low doses of Bisphenol-A on human placental cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benachour, Nora; Aris, Aziz, E-mail: aziz.aris@usherbrooke.c; Department of Obstetrics-Gynecology, University of Sherbrooke Hospital Centre, Quebec

Humans are exposed daily to a great number of xenobiotics and their metabolites present as pollutants. Bisphenol-A (BPA) is extensively used in a broad range of products including baby bottles, food-storage containers, medical equipment, and consumer electronics. Thus, BPA is the most common monomer for polycarbonates intended for food contact. Levels of this industrial product are found in maternal blood, amniotic fluid, follicular fluid, placental tissue, umbilical cord blood, and maternal urine. In this study, we investigated toxic effects of BPA concentrations close to levels found in serum of pregnant women on human cytotrophoblasts (CTB). These cells were isolated frommore » fresh placentas and exposed to BPA for 24 h. Our results showed that very low doses of BPA induce apoptosis (2 to 3 times) as assessed using M30 antibody immunofluorescent detection, and necrosis (1.3 to 1.7 times) as assessed through the cytosolic Adenylate Kinase (AK) activity after cell membrane damage. We also showed that BPA increased significantly the tumor-necrosis factor alpha (TNF-alpha) gene expression and protein excretion as measured by real-time RT-PCR and ELISA luminescent test, respectively. Moreover, we observed that induction of AK activation and TNF-alpha gene expression require lower levels of BPA than apoptosis or TNF-alpha protein excretion. Our findings suggest that exposure of placental cells to low doses of BPA may cause detrimental effects, leading in vivo to adverse pregnancy outcomes such as preeclampsia, intrauterine growth restriction, prematurity and pregnancy loss.« less

Toxic effects of low doses of Bisphenol-A on human placental cells.

PubMed

Benachour, Nora; Aris, Aziz

2009-12-15

Humans are exposed daily to a great number of xenobiotics and their metabolites present as pollutants. Bisphenol-A (BPA) is extensively used in a broad range of products including baby bottles, food-storage containers, medical equipment, and consumer electronics. Thus, BPA is the most common monomer for polycarbonates intended for food contact. Levels of this industrial product are found in maternal blood, amniotic fluid, follicular fluid, placental tissue, umbilical cord blood, and maternal urine. In this study, we investigated toxic effects of BPA concentrations close to levels found in serum of pregnant women on human cytotrophoblasts (CTB). These cells were isolated from fresh placentas and exposed to BPA for 24 h. Our results showed that very low doses of BPA induce apoptosis (2 to 3 times) as assessed using M30 antibody immunofluorescent detection, and necrosis (1.3 to 1.7 times) as assessed through the cytosolic Adenylate Kinase (AK) activity after cell membrane damage. We also showed that BPA increased significantly the tumor-necrosis factor alpha (TNF-alpha) gene expression and protein excretion as measured by real-time RT-PCR and ELISA luminescent test, respectively. Moreover, we observed that induction of AK activation and TNF-alpha gene expression require lower levels of BPA than apoptosis or TNF-alpha protein excretion. Our findings suggest that exposure of placental cells to low doses of BPA may cause detrimental effects, leading in vivo to adverse pregnancy outcomes such as preeclampsia, intrauterine growth restriction, prematurity and pregnancy loss.

High doses of S-methylcysteine cause hypoxia-induced cardiomyocyte apoptosis accompanied by engulfment of mitochondaria by nucleus.

PubMed

El-Magd, Mohammed A; Abdo, Walied S; El-Maddaway, Mustafa; Nasr, Nasr M; Gaber, Rasha A; El-Shetry, Eman S; Saleh, Ayman A; Alzahrani, Faisal Abdulrahman Ali; Abdelhady, Doaa H

2017-10-01

Despite its important role as a medicinal plant, some studies reported a toxic effect for garlic (Allium sativum) when given in higher doses. Herein, we investigated the possible cardiotoxic effects of high doses of S-methylcysteine (SMC), a water soluble organosulfur compound present in garlic. Rats were orally administered SMC at a low dose (50mg), high dose (150mg) and very high dose (300mg)/kg body weight, or saline (control) for 10days. High and very high doses of SMC resulted in a significant increase in serum cardiac injury biomarkers [aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and cardiac troponin T (cTnT)], as well as oxidative stress marker nitric oxide (NO) concentration in heart and a significant decrease in cardiac superoxide dismutase (SOD) activity. Moreover, ultrastructure findings in myocardium of rats treated by high and very high doses showed inter-bundle vacuolation, loss of myofibrils, and centripetal movement of mitochondria towards nucleus. The mitochondria were partially surrounded by nuclear membrane at high dose SMC, and completely engulfed by nucleus at very high dose. This centripetal movement of mitochondria accompanied by cardiomyocytes hypoxia-induced apoptosis as evident by increasing TUNEL positive cells as well as upregulation of apoptotic genes (caspase3 and Bax), hypoxia inducible factor 1 alpha (HIF1α), dynein light chain 1 (DYNLL1) and downregulation of the anti-apoptotic marker, Bcl2. We conclude that high and very high doses of SMC cause hypoxia induced cardiomyocyte apoptosis accompanied by engulfment of mitochondria by nucleus. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Transcriptomic Dose-Response Analysis for Mode of Action ...

EPA Pesticide Factsheets

Microarray and RNA-seq technologies can play an important role in assessing the health risks associated with environmental exposures. The utility of gene expression data to predict hazard has been well documented. Early toxicogenomics studies used relatively high, single doses with minimal replication. Thus, they were not useful in understanding health risks at environmentally-relevant doses. Until the past decade, application of toxicogenomics in dose response assessment and determination of chemical mode of action has been limited. New transcriptomic biomarkers have evolved to detect chemical hazards in multiple tissues together with pathway methods to study biological effects across the full dose response range and critical time course. Comprehensive low dose datasets are now available and with the use of transcriptomic benchmark dose estimation techniques within a mode of action framework, the ability to incorporate informative genomic data into human health risk assessment has substantially improved. The key advantage to applying transcriptomic technology to risk assessment is both the sensitivity and comprehensive examination of direct and indirect molecular changes that lead to adverse outcomes. Book Chapter with topic on future application of toxicogenomics technologies for MoA and risk assessment

Gene Expression Analysis Reveals New Possible Mechanisms of Vancomycin-Induced Nephrotoxicity and Identifies Gene Markers Candidates

PubMed Central

Dieterich, Christine; Puey, Angela; Lyn, Sylvia; Swezey, Robert; Furimsky, Anna; Fairchild, David; Mirsalis, Jon C.; Ng, Hanna H.

2009-01-01

Vancomycin, one of few effective treatments against methicillin-resistant Staphylococcus aureus, is nephrotoxic. The goals of this study were to (1) gain insights into molecular mechanisms of nephrotoxicity at the genomic level, (2) evaluate gene markers of vancomycin-induced kidney injury, and (3) compare gene expression responses after iv and ip administration. Groups of six female BALB/c mice were treated with seven daily iv or ip doses of vancomycin (50, 200, and 400 mg/kg) or saline, and sacrificed on day 8. Clinical chemistry and histopathology demonstrated kidney injury at 400 mg/kg only. Hierarchical clustering analysis revealed that kidney gene expression profiles of all mice treated at 400 mg/kg clustered with those of mice administered 200 mg/kg iv. Transcriptional profiling might thus be more sensitive than current clinical markers for detecting kidney damage, though the profiles can differ with the route of administration. Analysis of transcripts whose expression was changed by at least twofold compared with vehicle saline after high iv and ip doses of vancomycin suggested the possibility of oxidative stress and mitochondrial damage in vancomycin-induced toxicity. In addition, our data showed changes in expression of several transcripts from the complement and inflammatory pathways. Such expression changes were confirmed by relative real-time reverse transcription–polymerase chain reaction. Finally, our results further substantiate the use of gene markers of kidney toxicity such as KIM-1/Havcr1, as indicators of renal injury. PMID:18930951

Gene expression analysis reveals new possible mechanisms of vancomycin-induced nephrotoxicity and identifies gene markers candidates.

PubMed

Dieterich, Christine; Puey, Angela; Lin, Sylvia; Lyn, Sylvia; Swezey, Robert; Furimsky, Anna; Fairchild, David; Mirsalis, Jon C; Ng, Hanna H

2009-01-01

Vancomycin, one of few effective treatments against methicillin-resistant Staphylococcus aureus, is nephrotoxic. The goals of this study were to (1) gain insights into molecular mechanisms of nephrotoxicity at the genomic level, (2) evaluate gene markers of vancomycin-induced kidney injury, and (3) compare gene expression responses after iv and ip administration. Groups of six female BALB/c mice were treated with seven daily iv or ip doses of vancomycin (50, 200, and 400 mg/kg) or saline, and sacrificed on day 8. Clinical chemistry and histopathology demonstrated kidney injury at 400 mg/kg only. Hierarchical clustering analysis revealed that kidney gene expression profiles of all mice treated at 400 mg/kg clustered with those of mice administered 200 mg/kg iv. Transcriptional profiling might thus be more sensitive than current clinical markers for detecting kidney damage, though the profiles can differ with the route of administration. Analysis of transcripts whose expression was changed by at least twofold compared with vehicle saline after high iv and ip doses of vancomycin suggested the possibility of oxidative stress and mitochondrial damage in vancomycin-induced toxicity. In addition, our data showed changes in expression of several transcripts from the complement and inflammatory pathways. Such expression changes were confirmed by relative real-time reverse transcription-polymerase chain reaction. Finally, our results further substantiate the use of gene markers of kidney toxicity such as KIM-1/Havcr1, as indicators of renal injury.

NBCe1 expression is required for normal renal ammonia metabolism

PubMed Central

Handlogten, Mary E.; Osis, Gunars; Lee, Hyun-Wook; Romero, Michael F.; Verlander, Jill W.

2015-01-01

The mechanisms regulating proximal tubule ammonia metabolism are incompletely understood. The present study addressed the role of the proximal tubule basolateral electrogenic Na+-coupled bicarbonate cotransporter (NBCe1; Slc4a4) in renal ammonia metabolism. We used mice with heterozygous and homozygous NBCe1 gene deletion and compared these mice with their wild-type littermates. Because homozygous NBCe1 gene deletion causes 100% mortality before day 25, we studied mice at day 8 (±1 day). Both heterozygous and homozygous gene deletion caused a gene dose-related decrease in serum bicarbonate. The ability to lower urinary pH was intact, and even accentuated, with NBCe1 deletion. However, in contrast to the well-known effect of metabolic acidosis to increase urinary ammonia excretion, NBCe1 deletion caused a gene dose-related decrease in ammonia excretion. There was no identifiable change in proximal tubule structure by light microscopy. Examination of proteins involved in renal ammonia metabolism showed decreased expression of phosphate-dependent glutaminase and phosphoenolpyruvate carboxykinase, key enzymes in proximal tubule ammonia generation, and increased expression of glutamine synthetase, which recycles intrarenal ammonia and regenerates glutamine. Expression of key proteins involved in ammonia transport outside of the proximal tubule (rhesus B glycoprotein and rhesus C glycoprotein) was not significantly changed by NBCe1 deletion. We conclude from these findings that NBCe1 expression is necessary for normal proximal tubule ammonia metabolism. PMID:26224717

Early-life lead exposure results in dose- and sex-specific effects on weight and epigenetic gene regulation in weanling mice

PubMed Central

Faulk, Christopher; Barks, Amanda; Liu, Kevin; Goodrich, Jaclyn M; Dolinoy, Dana C

2013-01-01

Aims Epidemiological and animal data suggest that the development of adult chronic conditions is influenced by early-life exposure-induced changes to the epigenome. This study investigates the effects of perinatal lead (Pb) exposure on DNA methylation and bodyweight in weanling mice. Materials & methods Viable yellow agouti (Avy) mouse dams were exposed to 0, 2.1, 16 and 32 ppm Pb acetate before conception through weaning. Epigenetic effects were evaluated by scoring coat color of Avy/a offspring and quantitative bisulfite sequencing of two retrotransposon-driven (Avy and CDK5 activator-binding protein intracisternal A particle element) and two imprinted (Igf2 and Igf2r) loci in tail DNA. Results Maternal blood Pb levels were below the limit of detection in controls, and 4.1, 25.1 and 32.1 μg/dl for each dose, respectively. Pb exposure was associated with a trend of increased wean bodyweight in males (p = 0.03) and altered coat color in Avy/a offspring. DNA methylation at Avy and the CDK5 activator-binding protein intracisternal A-particle element was significantly different from controls following a cubic trend (p = 0.04; p = 0.01), with male-specific effects at the Avy locus. Imprinted genes did not shift in methylation across exposures. Conclusion Dose- and sex-specific responses in bodyweight and DNA methylation indicate that Pb acts on the epigenome in a locus-specific fashion, dependent on the genomic feature hosting the CpG site of interest, and that sex is a factor in epigenetic response. PMID:24059796

Genetic Basis of Haloperidol Resistance in Saccharomyces cerevisiae Is Complex and Dose Dependent

PubMed Central

Wang, Xin; Kruglyak, Leonid

2014-01-01

The genetic basis of most heritable traits is complex. Inhibitory compounds and their effects in model organisms have been used in many studies to gain insights into the genetic architecture underlying quantitative traits. However, the differential effect of compound concentration has not been studied in detail. In this study, we used a large segregant panel from a cross between two genetically divergent yeast strains, BY4724 (a laboratory strain) and RM11_1a (a vineyard strain), to study the genetic basis of variation in response to different doses of a drug. Linkage analysis revealed that the genetic architecture of resistance to the small-molecule therapeutic drug haloperidol is highly dose-dependent. Some of the loci identified had effects only at low doses of haloperidol, while other loci had effects primarily at higher concentrations of the drug. We show that a major QTL affecting resistance across all concentrations of haloperidol is caused by polymorphisms in SWH1, a homologue of human oxysterol binding protein. We identify a complex set of interactions among the alleles of the genes SWH1, MKT1, and IRA2 that are most pronounced at a haloperidol dose of 200 µM and are only observed when the remainder of the genome is of the RM background. Our results provide further insight into the genetic basis of drug resistance. PMID:25521586

[Relationship between the methylenetetrahydrofolate reductase gene polymorphism and adverse reactions of high-dose methotrexate in children with acute lymphocytic leukemia].

PubMed

Zheng, Miao-Miao; Yue, Li-Jie; Chen, Xiao-Wen; Wen, Fei-Qiu; Li, Chang-Gang; Yang, Chun-Lan; Xie, Cai; Ding, Hui

2013-03-01

To study the association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and toxicities after high-dose methotrexate (HD-MTX) infusion in children with acute lymphocytic leukemia (ALL). MTHFR variants in 52 children with ALL were determined by reverse transcriptase-polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing. Toxicities of children who received HD-MTX chemotherapy were evaluated according to the National Cancer Institute-Common Toxicity Criteria (NCI-CTC). The children carrying MTHFR 1298AC had a higher risk of developing thrombocytopenia compared with the carriers of the 1298 AA genotype (OR=13.7, 95%CI=1.18-159.36, P=0.036). There was no significant difference in HD-MTX chemotherapy-related adverse effects between the patients with different MTHFR C677T or G1793A genotypes. MTHFR A1298C polymorohism may associate with the toxicity of HD-MTX chemotherapy in children with ALL.

Genotoxic effects of high dose rate X-ray and low dose rate gamma radiation in ApcMin/+ mice.

PubMed

Graupner, Anne; Eide, Dag M; Brede, Dag A; Ellender, Michele; Lindbo Hansen, Elisabeth; Oughton, Deborah H; Bouffler, Simon D; Brunborg, Gunnar; Olsen, Ann Karin

2017-10-01

Risk estimates for radiation-induced cancer in humans are based on epidemiological data largely drawn from the Japanese atomic bomb survivor studies, which received an acute high dose rate (HDR) ionising radiation. Limited knowledge exists about the effects of chronic low dose rate (LDR) exposure, particularly with respect to the application of the dose and dose rate effectiveness factor. As part of a study to investigate the development of colon cancer following chronic LDR vs. acute HDR radiation, this study presents the results of genotoxic effects in blood of exposed mice. CBAB6 F1 Apc +/+ (wild type) and Apc Min/+ mice were chronically exposed to estimated whole body absorbed doses of 1.7 or 3.2 Gy 60 Co-γ-rays at a LDR (2.2 mGy h -1 ) or acutely exposed to 2.6 Gy HDR X-rays (1.3 Gy min -1 ). Genotoxic endpoints assessed in blood included chromosomal damage (flow cytometry based micronuclei (MN) assay), mutation analyses (Pig-a gene mutation assay), and levels of DNA lesions (Comet assay, single-strand breaks (ssb), alkali labile sites (als), oxidized DNA bases). Ionising radiation (ca. 3 Gy) induced genotoxic effects dependent on the dose rate. Chromosomal aberrations (MN assay) increased 3- and 10-fold after chronic LDR and acute HDR, respectively. Phenotypic mutation frequencies as well as DNA lesions (ssb/als) were modulated after acute HDR but not after chronic LDR. The Apc Min/+ genotype did not influence the outcome in any of the investigated endpoints. The results herein will add to the scant data available on genotoxic effects following chronic LDR of ionising radiation. Environ. Mol. Mutagen. 58:560-569, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.

Genotoxic effects of high dose rate X‐ray and low dose rate gamma radiation in ApcMin/+ mice

PubMed Central

Eide, Dag M.; Brede, Dag A.; Ellender, Michele; Lindbo Hansen, Elisabeth; Oughton, Deborah H.; Bouffler, Simon D.; Brunborg, Gunnar; Olsen, Ann Karin

2017-01-01

Risk estimates for radiation‐induced cancer in humans are based on epidemiological data largely drawn from the Japanese atomic bomb survivor studies, which received an acute high dose rate (HDR) ionising radiation. Limited knowledge exists about the effects of chronic low dose rate (LDR) exposure, particularly with respect to the application of the dose and dose rate effectiveness factor. As part of a study to investigate the development of colon cancer following chronic LDR vs. acute HDR radiation, this study presents the results of genotoxic effects in blood of exposed mice. CBAB6 F1 Apc+/+ (wild type) and ApcMin/+ mice were chronically exposed to estimated whole body absorbed doses of 1.7 or 3.2 Gy 60Co‐γ‐rays at a LDR (2.2 mGy h−1) or acutely exposed to 2.6 Gy HDR X‐rays (1.3 Gy min−1). Genotoxic endpoints assessed in blood included chromosomal damage (flow cytometry based micronuclei (MN) assay), mutation analyses (Pig‐a gene mutation assay), and levels of DNA lesions (Comet assay, single‐strand breaks (ssb), alkali labile sites (als), oxidized DNA bases). Ionising radiation (ca. 3 Gy) induced genotoxic effects dependent on the dose rate. Chromosomal aberrations (MN assay) increased 3‐ and 10‐fold after chronic LDR and acute HDR, respectively. Phenotypic mutation frequencies as well as DNA lesions (ssb/als) were modulated after acute HDR but not after chronic LDR. The ApcMin/+ genotype did not influence the outcome in any of the investigated endpoints. The results herein will add to the scant data available on genotoxic effects following chronic LDR of ionising radiation. Environ. Mol. Mutagen. 58:560–569, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society PMID:28856770

Real-time quantitative reverse transcription-PCR analysis of expression stability of Aggregatibacter actinomycetemcomitans fimbria-associated gene in response to photodynamic therapy.

PubMed

Pourhajibagher, Maryam; Monzavi, Abbas; Chiniforush, Nasim; Monzavi, Mohammad Moein; Sobhani, Shaghayegh; Shahabi, Sima; Bahador, Abbas

2017-06-01

Aggregatibacter actinomycetemcomitans is an etiological agent of both chronic and aggressive periodontitis. Dissemination of A. actinomycetemcomitans from the oral cavity and initiation of systemic infections has led to new approaches for treatment being needed. In this study, a series of experiments presented investigated the effect of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) on cell viability and expression of fimbria-associated gene (rcpA) in A. actinomycetemcomitans. To determine the dose-depended effects of aPDT, A. actinomycetemcomitans ATCC 33384 strain photosensitized with MB was irradiated with diode laser following bacterial viability measurements. Cell-surviving assay and expression ratio of rcpA were assessed by colony forming unit and real-time quantitative reverse transcription-PCR (qRT-PCR) assays, respectively. In the current study, MB-mediated aPDT using 100μg/mL showed significant reduction in A. actinomycetemcomitans growth when compared to the control (P<0.05). Sub-lethal dose of aPDT against A. actinomycetemcomitans was 25μg/mL MB at fluency of 93.75J/cm 2 . Sub-lethal dose of aPDT could lead to about four-fold suppression of expression of rcpA. High doses of MB-mediated aPDT could potentially exhibit antimicrobial activity, and the expression of rcpA as an important virulence factor of this strain is reduced in cells surviving aPDT with MB. So, aPDT can be a valuable tool for the treatment of A. actinomycetemcomitans infections. Copyright © 2017 Elsevier B.V. All rights reserved.

Engineered Mesenchymal Cells Improve Passive Immune Protection Against Lethal Venezuelan Equine Encephalitis Virus Exposure

PubMed Central

Braid, Lorena R.; Davies, John E.; Nagata, Les P.

2016-01-01

Mesenchymal stromal cells (MSCs) are being exploited as gene delivery vectors for various disease and injury therapies. We provide proof-of-concept that engineered MSCs can provide a useful, effective platform for protection against infectious disease. Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne pathogen affecting humans and equines and can be used in bio-warfare. No licensed vaccine or antiviral agent currently exists to combat VEEV infection in humans. Direct antibody administration (passive immunity) is an effective, but short-lived, method of providing immediate protection against a pathogen. We compared the protective efficacy of human umbilical cord perivascular cells (HUCPVCs; a rich source of MSCs), engineered with a transgene encoding a humanized VEEV-neutralizing antibody (anti-VEEV), to the purified antibody. In athymic mice, the anti-VEEV antibody had a half-life of 3.7 days, limiting protection to 2 or 3 days after administration. In contrast, engineered HUCPVCs generated protective anti-VEEV serum titers for 21–38 days after a single intramuscular injection. At 109 days after transplantation, 10% of the mice still had circulating anti-VEEV antibody. The mice were protected against exposure to a lethal dose of VEEV by an intramuscular pretreatment injection with engineered HUCPVCs 24 hours or 10 days before exposure, demonstrating both rapid and prolonged immune protection. The present study is the first to describe engineered MSCs as gene delivery vehicles for passive immunity and supports their utility as antibody delivery vehicles for improved, single-dose prophylaxis against endemic and intentionally disseminated pathogens. Significance Direct injection of monoclonal antibodies (mAbs) is an important strategy to immediately protect the recipient from a pathogen. This strategy is critical during natural outbreaks or after the intentional release of bio-weapons. Vaccines require weeks to become effective, which is not practical for first responders immediately deployed to an infected region. However, mAb recipients often require booster shots to maintain protection, which is expensive and impractical once the first responders have been deployed. The present study has shown, for the first time, that mesenchymal stromal cells are effective gene delivery vehicles that can significantly improve mAb-mediated immune protection in a single, intramuscular dose of engineered cells. Such a cell-based delivery system can provide extended life-saving protection in the event of exposure to biological threats using a more practical, single-dose regimen. PMID:27334491

Vaccination of plasmid DNA encoding ORF81 gene of CJ strains of KHV provides protection to immunized carp.

PubMed

Zhou, Jingxiang; Xue, Jiangdong; Wang, Qiuju; Zhu, Xia; Li, Xingwei; Lv, Wenliang; Zhang, Dongming

2014-06-01

In order to construct the recombinant plasmid of pIRES-ORF81, the nucleic acid isolated from Koi herpes virus-CJ (KHV-CJ) strains was used as a template to insert the ORF81 gene fragments amplified by PCR into the pIRES-neo, a kind of eukaryotic expression vector. Using Western blotting analysis, it was verified that ORF81 gene protein can be expressed correctly by pIRES-ORF81, after MFC cells were transfected. The recombinant plasmid pIRES-ORF81 was set into three immunization dose gradients: 1, 10, and 50 μg/carp. Empty plasmid group, PBS group, and blank control group were set simultaneously. Giving intramuscular injections to healthy carps with an average body mass of 246 ± 20 g, indirect ELISA was used to regularly determine antibody levels after three times immunization injection. Neutralizing antibodies were detected by neutralization assay. The results of inoculation tests showed that the pIRES-ORF81 recombinant plasmid can induce the production of carp-specific antibodies. The differences of immune effect between the three different doses of immune gradients were not significant (P > 0.05), but they can induce the production of neutralizing antibodies. After 25 d of inoculation, carp mortality of pIRES-neo empty vector treatment groups was 85%, while the carp mortality of eukaryotic expression recombinant plasmid pIRES-ORF81 injected with three different doses of immune gradients was 20, 17.5, and 12.5%, respectively. Differences in comparison to the control group were highly significant (P < 0.01). However, histopathological section of immunohistochemistry organization revealed no significant changes. It demonstrated that the DNA vaccine pIRES-ORF81 constructed in the experiment displayed a good protective effect against KHV, which had the potential to industrial applications.

Shikonin Inhibites Migration and Invasion of Thyroid Cancer Cells by Downregulating DNMT1

PubMed Central

Zhang, Yue; Sun, Bin; Huang, Zhi

2018-01-01

Background Shikonin is a component of Chinese herbal medicine. The aim of this study was to investigate the effects of shikonin on cell migration of papillary thyroid cancer cells of the TPC-1 cell line in vitro and expression levels of the phosphate and tensin homolog deleted on chromosome 10 (PTEN) and DNA methyltransferase 1 (DNMT1) genes. Material/Methods The Cell Counting Kit-8 (CCK-8) assay was performed to evaluate the proliferation of TPC-1 papillary thyroid cancer cells, and the normal thyroid cells, HTori-3, in vitro. A transwell motility assay was used to analyze the migration of TPC-1 cells. Western blot was performed to determine the expression levels of PTEN and DNMT1 genes. A methylation-specific polymerase chain reaction (PCR) (MSP) assay was used to evaluate the methylation of PTEN. Results Following treatment with shikonin, the cell survival rate of TPC-1 cells decreased in a dose-dependent manner; the inhibitory effects on HTori-3 cells were less marked. Shikonin inhibited TPC-1 cell migration and invasion in a dose-dependent manner. The methylation of PTEN was suppressed by shikonin, which also reduced the expression of DNMT1 in a dose-dependent manner, and increased the expression of PTEN. Overexpression of DNMT1 promoted the migration of TPC-1 cells and the methylation of PTEN. Levels of protein expression of PTEN in TPC-1 cells treated with shikonin decreased, and were increased by DNMT1 knockdown. Conclusions Shikonin suppressed the expression of DNMT1, reduced PTEN gene methylation, and increased PTEN protein expression, leading to the inhibition of TPC-1 cell migration. PMID:29389913

Growth of Arabidopsis seedlings on high fungal doses of Piriformospora indica has little effect on plant performance, stress, and defense gene expression in spite of elevated jasmonic acid and jasmonic acid-isoleucine levels in the roots

PubMed Central

Vahabi, Khabat; Camehl, Iris; Sherameti, Irena; Oelmüller, Ralf

2013-01-01

The endophytic fungus Piriformospora indica colonizes the roots of many plant species including Arabidopsis and promotes their performance, biomass, and seed production as well as resistance against biotic and abiotic stress. Imbalances in the symbiotic interaction such as uncontrolled fungal growth result in the loss of benefits for the plants and activation of defense responses against the microbe. We exposed Arabidopsis seedlings to a dense hyphal lawn of P. indica. The seedlings continue to grow, accumulate normal amounts of chlorophyll, and the photosynthetic parameters demonstrate that they perform well. In spite of high fungal doses around the roots, the fungal material inside the roots was not significantly higher when compared with roots that live in a beneficial symbiosis with P. indica. Fifteen defense- and stress-related genes including PR2, PR3, PAL2, and ERF1 are only moderately upregulated in the roots on the fungal lawn, and the seedlings did not accumulate H2O2/radical oxygen species. However, accumulation of anthocyanin in P. indica-exposed seedlings indicates stress symptoms. Furthermore, the jasmonic acid (JA) and jasmonic acid-isoleucine (JA-Ile) levels were increased in the roots, and consequently PDF1.2 and a newly characterized gene for a 2-oxoglurate and Fe2+-dependent oxygenase were upregulated more than 7-fold on the dense fungal lawn, in a JAR1- and EIN3-dependent manner. We conclude that growth of A. thaliana seedlings on high fungal doses of P. indica has little effect on the overall performance of the plants although elevated JA and JA-Ile levels in the roots induce a mild stress or defense response. PMID:24047645

Chronic nicotine-induced changes in gene expression of delta and kappa-opioid receptors and their endogenous ligands in the mesocorticolimbic system of the rat.

PubMed

Ugur, Muzeyyen; Kaya, Egemen; Gozen, Oguz; Koylu, Ersin O; Kanit, Lutfiye; Keser, Aysegul; Balkan, Burcu

2017-09-01

Delta and kappa opioid receptors (DOR and KOR, respectively) and their endogenous ligands, proenkephalin (PENK) and prodynorphin (PDYN)-derived opioid peptides are proposed as important mediators of nicotine reward. This study investigated the regulatory effect of chronic nicotine treatment on the gene expression of DOR, KOR, PENK and PDYN in the mesocorticolimbic system. Three groups of rats were injected subcutaneously with nicotine at doses of 0.2, 0.4, or 0.6 mg/kg/day for 6 days. Rats were decapitated 1 hr after the last dose on day six, as this timing coincides with increased dopamine release in the mesocorticolimbic system. mRNA levels in the ventral tegmental area (VTA), lateral hypothalamic area (LHA), amygdala (AMG), dorsal striatum (DST), nucleus accumbens, and medial prefrontal cortex were measured by quantitative real-time PCR. Our results showed that nicotine upregulated DOR mRNA in the VTA at all of the doses employed, in the AMG at the 0.4 and 0.6 mg/kg doses, and in the DST at the 0.4 mg/kg dose. Conversely, PDYN mRNA was reduced in the LHA with 0.6 mg/kg nicotine and in the AMG with 0.4 mg/kg nicotine. KOR mRNA was also decreased in the DST with 0.6 mg/kg nicotine. Nicotine did not regulate PENK mRNA in any brain region studied. © 2017 Wiley Periodicals, Inc.

Expression of Cyclin d1 protein and CCND1 та PNKP genes in peripheral blood mononuclear cells in clean up worker of Chornobyl accident with different state of immune system.

PubMed

Bazyka, D A; Kubashko, A V; Ilyenko, I M; Belyaev, O A; Pleskach, O J

2015-12-01

to investigate the Cyclin D1+ cells levels changes, associated CCND1 and PNKP genes in peripheral blood mononuclear cells in clean up workers of Chornobyl accident with different state of immune system in depends on the dose irradiation. Relative level of Cyclin D1+cells in peripheral blood mononuclears of 39 clean up workers, men, irradiated in dose range (0,01-2,00) Gy have been analyzed. Immunological status of examinee' subjects was determined by CD3/19, CD4/8, CD3/HLA DR, СD3/16/56 testing using flow cytometry method and Ig A,M,G testing by immunoenzymatic assay in blood. CCND1 та PNKP gene expression, which associated with Cyclin D1 metabolism, was conducted using PCR real time method. The obtained results were compared in relation to data from 18 healthy men, who had no contact with ionizing radiation over then nature background. Аnalyzed data of the nuclear controller of cell cycle - Cyclin D1 protein expression changes and related CCND1 та PNKP genes in peripheral blood mononuclear cells in clean up workers Chornobyl accident with different status of immune system in remote period after exposure is represented. It is shown, that in examinees' subjects exposed in dose > 0,1 Gy percentage of Суclin D1+ cells is elevated against normal range and correlates with dose of radiation (rs = 0,417, p = 0,048). Normal range deflation of relative amount of Cyclin D1+cells connects with changes in cellular and humoral immunity. Decline of relative amount of Cyclin D1+ cells below the control level following CD3+ lymphocytes decrease and CD3 16+56+ elevation in clean up workers exposed in dose < 0,35 Gy. Increase of relative amount of Cyclin D1+ cells above the control range associates with CD3+ fall together with tendency of CD3+16+56+ lymphocytes fall that attends the IgG elevation in examinees' subjects with dose > 0,35 Gy. Percentage of Cyclin D1+ cells correlates with CD3 16+56+ (rs = 0,872, p = 0,049), CD8+ and IgG (rs = 0,683, p = 0,042; rs = 0,809, p = 0,014), CD4+ (rs = 0,602, p = 0,029), CD19+ and IgM (rs = 0,604, p = 0,017; rs = 0,538, p = 0,038) under condition of increased level CD4+, CD19+, Іreg. and IgG accordantly. Reviled decrease the CCND1 and PNKP gene expression in clean up workers exposed in dose > 0,1 Gy following appearance of correlation between (relative quantification) RQ PNKP and irradiation dose (rs = 0,638, p = 0,035) and also with RQ PNKP and percentage of Cyclin D1+ cells (rs = 0,792, p = 0,034).Concusions. Reveled changes in expression of Cyclin D1+ cells and regulation of related genes may point on possi ble radiation associated firm molecular disturbances occurred during elimination of consequences of Chornobyl accident, that could be a potential basis for cell and humoral communicative links breach in immune system result ing in elevation of stochastic effects like oncopathology in clean up workers of Chornobyl accident in remote peri od after exposure. D. A. Bazyka, A. V. Kubashko, I. M. Ilyenko, O. A. Belyaev, O. J. Pleskach.

A phase 1 trial of ABT-510 concurrent with standard chemoradiation for patients with newly diagnosed glioblastoma.

PubMed

Nabors, Louis B; Fiveash, John B; Markert, James M; Kekan, Manasi S; Gillespie, George Y; Huang, Zhi; Johnson, Martin J; Meleth, Sreelatha; Kuo, Huichien; Gladson, Candece L; Fathallah-Shaykh, Hassan M

2010-03-01

To determine the maximum tolerated dose of ABT-510, a thrombospondin-1 mimetic drug with antiangiogenic properties, when used concurrently with temozolomide and radiotherapy in patients with newly diagnosed glioblastoma. Phase 1 dose-escalation clinical trial. Comprehensive Cancer Center, University of Alabama at Birmingham. Patients A total of 23 patients with newly diagnosed, histologically verified glioblastoma enrolled between April 2005 and January 2007. Four cohorts of 3 patients each received subcutaneous ABT-510 injection at doses of 20, 50, 100, or 200 mg/d. The maximum cohort was expanded to 14 patients to obtain additional safety and gene expression data. The treatment plan included 10 weeks of induction phase (temozolomide and radiotherapy with ABT-510 for 6 weeks plus ABT-510 monotherapy for 4 weeks) followed by a maintenance phase of ABT-510 and monthly temozolomide. Patients were monitored with brain magnetic resonance imaging and laboratory testing for dose-limiting toxicities, defined as grades 3 or 4 nonhematological toxicities and grade 4 hematological toxicities. Therapy was discontinued if 14 maintenance cycles were completed, disease progression occurred, or if the patient requested withdrawal. Disease progression, survival statistics, and gene expression arrays were analyzed. There were no grade 3 or 4 dose-limiting toxicity events that appeared related to ABT-510 for the dose range of 20 to 200 mg/d. A maximum tolerated dose was not defined. Most adverse events were mild, and injection-site reactions. The median time to tumor progression was 45.9 weeks, and the median overall survival time was 64.4 weeks. Gene expression analysis using TaqMan low-density arrays identified angiogenic genes that were differentially expressed in the brains of controls compared with patients with newly diagnosed glioblastoma, and identified FGF-1 and TIE-1 as being downregulated in patients who had better clinical outcomes. ABT-510, at subcutaneous doses up to 200 mg/d, is tolerated well with concurrent temozolomide and radiotherapy in patients with newly diagnosed glioblastoma, and low-density arrays provide a useful method of exploring gene expression profiles.

Imatinib induces up-regulation of NM23, a metastasis suppressor gene, in human Hepatocarcinoma (HepG2) Cell Line

PubMed Central

Keshavarz-Pakseresht, Behta; Shandiz, Seyed Ataollah Sadat; Baghbani-arani, Fahimeh

2017-01-01

Aim: The present study investigated the anti-tumor activity of Imatinib mesylate through modulation of NM23 gene expression in human hepatocellular carcinoma (HepG2) cell line. Background: Hepatocellular carcinoma (HCC) is considered to be the third leading cause of cancer related death worldwide. Down regulation of NM23, a metastasis suppressor gene, has been associated with several types of malignant cancer. Recently, effects of Imatinib mesylate, a first member of tyrosine kinases inhibitors, were indicated in research and treatment of different malignant tumors. Methods: Cell viability was quantitated by MTT assay after HepG2 cells exposure to Imatinib mesylate at various concentrations of 0, 1.56, 3.125, 6.25, 12.5, 25,50μM for 24 hours. Also, quantitative real time PCR technique was applied for the detection of NM23 gene expression in HepG2 cell line. Results: There was a dose dependent increase in the cytotoxicity effect of imatinib. The real time PCR results demonstrated that inhibitory effect of Imatinib mesylate on viability via up regulation of NM23 gene expression compared to GAPDH gene (internal control gene) in cancer cells. Conclusion: According to our findings, imatinib can modulate metastasis by enhancing Nm23 gene expression in human hepatocellular carcinoma (HepG2) cell line. PMID:28331561

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice.

PubMed

Xu, Yun-Yan; Xu, Ya-Sha; Wang, Yuan; Wu, Qin; Lu, Yuan-Fu; Liu, Jie; Shi, Jing-Shan

2017-10-01

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice. Mice were given DNLA at doses of 10-80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis. Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα. DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders. © 2017 Royal Pharmaceutical Society.

Altered gene expression by low-dose arsenic exposure in humans and cultured cardiomyocytes: Assessment by real-time PCR array

EPA Science Inventory

Arsenic contamination in drinking water has become a great public health concern worldwide. Chronic arsenic exposure results in higher risk of skin, lung and bladder cancer, as well as cardiovascular disease and diabetes. The purpose of this study was to investigate the effects o...

INDUCTION OF CYTOCHROME P450 ISOFORMS IN RAT LIVER BY TWO CONAZOLES, TRIADIMEFON AND MYCLOBUTANIL

EPA Science Inventory

1. This study was undertaken to examine the inductive effects of two triazole antifungal agents, myclobutanil and triadimefon on the expression of hepatic cytochrome P450 (CYP) genes and on the activities of CYP enzymes in male Sprague-Dawley rats. Rats were dosed by gavage for 1...

Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

NASA Technical Reports Server (NTRS)

George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

2009-01-01

Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase, DNA-PK activity. Chromosomes were analyzed using the fluorescence in-situ hybridization (FISH) chromosome painting method in cells at the first division post-irradiation and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma radiation induced higher yields of both simple and complex exchanges in the DSB repair defective cells than in the normal cells. The quadratic dose-response terms for both chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further investigate the sensitivity differences for low and low high doses, we performed chronic low dose-rate irradiation, and have begun studies with ATM and Nibrin inhibitors and siRNA knockout of these proteins. Results support the conclusion that for the endpoint of simple chromosomal aberrations (translocation or dicentrics), the increased radiation sensitivity of AT cells found at high doses (>1 Gy) does not carry over to low doses or doserates, while NBS cells show increased sensitivity for both high and low dose exposures.

Molecular pathways underlying inhibitory effect of antimicrobial peptide Nal-P-113 on bacteria biofilms formation of Porphyromonas gingivalis W83 by DNA microarray.

PubMed

Wang, Hong-Yan; Lin, Li; Tan, Li-Si; Yu, Hui-Yuan; Cheng, Jya-Wei; Pan, Ya-Ping

2017-02-17

Wound-related infection remains a major challenge for health professionals. One disadvantage in conventional antibiotics is their inability to penetrate biofilms, the main protective strategy for bacteria to evade irradiation. Previously, we have shown that synthetic antimicrobial peptides could inhibit bacterial biofilms formation. In this study, we first delineated how Nal-P-113, a novel antimicrobial peptide, exerted its inhibitory effects on Porphyromonas gingivalis W83 biofilms formation at a low concentration. Secondly, we performed gene expression profiling and validated that Nal-P-113 at a low dose significantly down-regulated genes related to mobile and extrachromosomal element functions, transport and binding proteins in Porphyromonas gingivalis W83. These findings suggest that Nal-P-113 at low dose is sufficient to inhibit the formation of biofilms although Porphyromonas gingivalis W83 may maintain its survival in the oral cavity. The newly discovered molecular pathways may add the knowledge of developing a new strategy to target bacterial infections in combination with current first-line treatment in periodontitis.

The Effect of Diagnostic Absorbed Doses from 131I on Human Thyrocytes in Vitro.

PubMed

Adamczewski, Zbigniew; Stasiołek, Mariusz; Karwowski, Bolesław; Dedecjus, Marek; Orszulak-Michalak, Daria; Merecz, Anna; Śliwka, Przemysław W; Puła, Bartosz; Lewiński, Andrzej

2015-06-29

Administration of diagnostic activities of 131I, performed in order to detect thyroid remnants after surgery and/or thyroid cancer recurrence/metastases, may lead to reduction of iodine uptake. This phenomenon is called "thyroid stunning". We estimated radiation absorbed dose-dependent changes in genetic material, in particular in sodium iodide symporter (NIS) gene promoter, and NIS protein level in human thyrocytes (HT). We used unmodified HT isolated from patients subjected to thyroidectomy exposed to 131I in culture. The different 131I activities applied were calculated to result in absorbed doses of 5, 10, and 20 Gy. According to flow cytometry analysis and comet assay, 131I did not influence the HT viability in culture. Temporary increase of 8-oxo-dG concentration in HT directly after 24 h (p < 0.05) and increase in the number of AP-sites 72 h after termination of exposition to 20 Gy dose (p < 0.0001) were observed. The signs of dose-dependent DNA damage were not associated with essential changes in the NIS expression on mRNA and protein levels. Our observation constitutes a first attempt to evaluate the effect of the absorbed dose of 131I on HT. The results have not confirmed the theory that the "thyroid stunning" reduces the NIS protein synthesis.

Carnosic acid inhibits the growth of ER-negative human breast cancer cells and synergizes with curcumin.

PubMed

Einbond, Linda Saxe; Wu, Hsan-Au; Kashiwazaki, Ryota; He, Kan; Roller, Marc; Su, Tao; Wang, Xiaomei; Goldsberry, Sarah

2012-10-01

Studies indicate that extracts and purified components, including carnosic acid, from the herb rosemary display significant growth inhibitory activity on a variety of cancers. This paper examines the ability of rosemary/carnosic acid to inhibit the growth of human breast cancer cells and to synergize with curcumin. To do this, we treated human breast cancer cells with rosemary/carnosic acid and assessed effects on cell proliferation, cell cycle distribution, gene expression patterns, activity of the purified Na/K ATPase and combinations with curcumin. Rosemary/carnosic acid potently inhibits proliferation of ER-negative human breast cancer cells and induces G1 cell cycle arrest. Further, carnosic acid is selective for MCF7 cells transfected for Her2, indicating that Her2 may function in its action. To reveal primary effects, we treated ER-negative breast cancer cells with carnosic acid for 6h. At a low dose, 5 μg/ml (15 μM), carnosic acid activated the expression of 3 genes, induced through the presence of antioxidant response elements, including genes involved in glutathione biosynthesis (CYP4F3, GCLC) and transport (SLC7A11). At a higher dose, 20 μg/ml, carnosic acid activated the expression of antioxidant (AKR1C2, TNXRD1, HMOX1) and apoptosis (GDF15, PHLDA1, DDIT3) genes and suppressed the expression of inhibitor of transcription (ID3) and cell cycle (CDKN2C) genes. Carnosic acid exhibits synergy with turmeric/curcumin. These compounds inhibited the activity of the purified Na-K-ATPase which may contribute to this synergy. Rosemary/carnosic acid, alone or combined with curcumin, may be useful to prevent and treat ER-negative breast cancer. Copyright © 2012 Elsevier B.V. All rights reserved.

BRCA1 and TP53 Gene-Mutations: Family Predisposition and Radioecological Risk of Developing Breast Cancer.

PubMed

Apsalikov, Bakytbek; Manambaeva, Zukhra; Ospanov, Erlan; Massabayeva, Meruyert; Zhabagin, Kuantkan; Zhagiparova, Zhanar; Maximov, Vladymir; Voropaeva, Elena; Apsalikov, Kazbek; Belikhina, Tatiana; Abdrahmanov, Ramil; Cherepkova, Elena; Tanatarov, Sayat; Massadykov, Adilzhan; Urazalina, Naylia

2016-01-01

Frequencies of polymorphisms of genes BRCA1 and TP53 in breast cancer (BC) patients with a BC family history and radiation history were assessed and compared in the Semey region of Kazakhstan. The study included 60 women directly irradiated by the activities of the Semipalatinsk test site with a calculated effective equivalent dose of 500 mSv and their first generation descendants (group BC+Her+Exp); 65 women with family BC and absence of radiological history - the effective equivalent dose due to anthropogenic sources not exceeding 50 mSv (group BC+Her-Exp). The comparison group consisted of 65 women patients with breast cancer without family and radiological history (BC-Her-Exp). The control group comprised 60 women without breast cancer and without family and radiological history (nonBC). We carried out the genotyping of the polymorphisms c.2311T>C, c.4308T>C and 5382insC of the BRCA1 gene and rs1042522 of the TP53 gene. The frequency of the polymorphism c.2311T>C was significantly higher in patients of the group BC+Her+Exp than in healthy women, and of the polymorphism 5382insC in BC+Her+Exp compared to all other groups. The frequency of the rs1042522 polymorphism of TP53 was significantly higher in all groups of patients with breast cancer compared with the control group. Differences between groups of women with breast cancer were significant only in BC+Her+Exp vs. BC+Her-Exp. Combinations of polymorphisms of the genes BRCA1 and TP53 predominated in women with a family and radiological history.

Radiation-induced genomic instability: radiation quality and dose response

NASA Technical Reports Server (NTRS)

Smith, Leslie E.; Nagar, Shruti; Kim, Grace J.; Morgan, William F.

2003-01-01

Genomic instability is a term used to describe a phenomenon that results in the accumulation of multiple changes required to convert a stable genome of a normal cell to an unstable genome characteristic of a tumor. There has been considerable recent debate concerning the importance of genomic instability in human cancer and its temporal occurrence in the carcinogenic process. Radiation is capable of inducing genomic instability in mammalian cells and instability is thought to be the driving force responsible for radiation carcinogenesis. Genomic instability is characterized by a large collection of diverse endpoints that include large-scale chromosomal rearrangements and aberrations, amplification of genetic material, aneuploidy, micronucleus formation, microsatellite instability, and gene mutation. The capacity of radiation to induce genomic instability depends to a large extent on radiation quality or linear energy transfer (LET) and dose. There appears to be a low dose threshold effect with low LET, beyond which no additional genomic instability is induced. Low doses of both high and low LET radiation are capable of inducing this phenomenon. This report reviews data concerning dose rate effects of high and low LET radiation and their capacity to induce genomic instability assayed by chromosomal aberrations, delayed lethal mutations, micronuclei and apoptosis.

DNA microarray unravels rapid changes in transcriptome of MK-801 treated rat brain

PubMed Central

Kobayashi, Yuka; Kulikova, Sofya P; Shibato, Junko; Rakwal, Randeep; Satoh, Hiroyuki; Pinault, Didier; Masuo, Yoshinori

2015-01-01

AIM: To investigate the impact of MK-801 on gene expression patterns genome wide in rat brain regions. METHODS: Rats were treated with an intraperitoneal injection of MK-801 [0.08 (low-dose) and 0.16 (high-dose) mg/kg] or NaCl (vehicle control). In a first series of experiment, the frontoparietal electrocorticogram was recorded 15 min before and 60 min after injection. In a second series of experiments, the whole brain of each animal was rapidly removed at 40 min post-injection, and different regions were separated: amygdala, cerebral cortex, hippocampus, hypothalamus, midbrain and ventral striatum on ice followed by DNA microarray (4 × 44 K whole rat genome chip) analysis. RESULTS: Spectral analysis revealed that a single systemic injection of MK-801 significantly and selectively augmented the power of baseline gamma frequency (30-80 Hz) oscillations in the frontoparietal electroencephalogram. DNA microarray analysis showed the largest number (up- and down- regulations) of gene expressions in the cerebral cortex (378), midbrain (376), hippocampus (375), ventral striatum (353), amygdala (301), and hypothalamus (201) under low-dose (0.08 mg/kg) of MK-801. Under high-dose (0.16 mg/kg), ventral striatum (811) showed the largest number of gene expression changes. Gene expression changes were functionally categorized to reveal expression of genes and function varies with each brain region. CONCLUSION: Acute MK-801 treatment increases synchrony of baseline gamma oscillations, and causes very early changes in gene expressions in six individual rat brain regions, a first report. PMID:26629322

Origanum Majoranum Extract Modulates Gene Expression, Hepatic and Renal Changes in a Rat Model of Type 2 Diabetes

PubMed Central

Soliman, Mohamed Mohamed; Abdo Nassan, Mohamed; Ismail, Tamer Ahmed

2016-01-01

The present study was conducted to test the effect of Origanum Majoranum Extract (OME) of leaves on alterations induced in a model of type 2 diabetic rats. Adult male Wistar rats were fed high fat diet for 3 weeks and injected a single dose of streptozotocin (35 mg/kg) intraperitoneally to induce type 2 diabetic rats. Diabetic rats were given aqueous extract of OME in a dose of 20 mg/kg orally for 3 weeks. Changes in lipid profiles, glucose, insulin, expression of some genes related to glucose metabolism and histopathological changes in liver and kidney were examined. Administration of OME improved and normalized dyslipidemia recorded in type 2 diabetic rats together with reduction in glucose and insulin levels. OME induced up-regulation in gene expression of glucose [adiponectin and glucose transporter-2 (GLUT-2)] and lipid metabolism [lipoprotein lipase (LPL)]. Moreover, OME normalized histopathological changes occurred in liver and kidney of diabetic rats. OME decreased lipids accumulation in liver and kidney and increased regeneration of hepatic parenchyma and restored normal renal architecture with disappearance of fat droplets. In conclusion, OME improved dyslipidemia associated with type 2 diabetes through regulation of genes related to glucose and lipid metabolism. PMID:28228803

Enhanced intestinal epithelial cell proliferation in diabetic rats correlates with β-catenin accumulation.

PubMed

Dorfman, Tatiana; Pollak, Yulia; Sohotnik, Rima; Coran, Arnold G; Bejar, Jacob; Sukhotnik, Igor

2015-09-01

The Wnt/β-catenin signaling cascade is implicated in the control of stem cell activity, cell proliferation, and cell survival of the gastrointestinal epithelium. Recent evidence indicates that the Wnt/β-catenin pathway is activated under diabetic conditions. The purpose of this study was to evaluate the role of Wnt/β-catenin signaling during diabetes-induced enteropathy in a rat model. Male rats were divided into three groups: control rats received injections of vehicle; diabetic rats received injections of one dose of streptozotocin (STZ); and diabetic-insulin rats received injections of STZ and were treated with insulin given subcutaneously at a dose of 1 U/kg twice daily. Rats were killed on day 7. Wnt/β-catenin-related genes and expression of proteins was determined using real-time PCR, western blotting, and immunohistochemistry. Among 13 genes identified by real-time PCR, seven genes were upregulated in diabetic rats compared with control animals including the target genes c-Myc and Tcf4. Diabetic rats also showed a significant increase in β-catenin protein compared with control animals. Treatment of diabetic rats attenuated the stimulating effect of diabetes on intestinal cell proliferation and Wnt/β-catenin signaling. In conclusion, enhanced intestinal epithelial cell proliferation in diabetic rats correlates with β-catenin accumulation. © 2015 Society for Endocrinology.

Low-Dose, Long-Wave UV Light Does Not Affect Gene Expression of Human Mesenchymal Stem Cells

PubMed Central

Wong, Darice Y.; Ranganath, Thanmayi; Kasko, Andrea M.

2015-01-01

Light is a non-invasive tool that is widely used in a range of biomedical applications. Techniques such as photopolymerization, photodegradation, and photouncaging can be used to alter the chemical and physical properties of biomaterials in the presence of live cells. Long-wave UV light (315 nm–400 nm) is an easily accessible and commonly used energy source for triggering biomaterial changes. Although exposure to low doses of long-wave UV light is generally accepted as biocompatible, most studies employing this wavelength only establish cell viability, ignoring other possible (non-toxic) effects. Since light exposure of wavelengths longer than 315 nm may potentially induce changes in cell behavior, we examined changes in gene expression of human mesenchymal stem cells exposed to light under both 2D and 3D culture conditions, including two different hydrogel fabrication techniques, decoupling UV exposure and radical generation. While exposure to long-wave UV light did not induce significant changes in gene expression regardless of culture conditions, significant changes were observed due to scaffold fabrication chemistry and between cells plated in 2D versus encapsulated in 3D scaffolds. In order to facilitate others in searching for more specific changes between the many conditions, the full data set is available on Gene Expression Omnibus for querying. PMID:26418040

CHOLESTEROL-RELATED GENETIC RISK SCORES ARE ASSOCIATED WITH HYPOMETABOLISM IN ALZHEIMER’S-AFFECTED BRAIN REGIONS

PubMed Central

Reiman, Eric M.; Chen, Kewei; Caselli, Richard J.; Alexander, Gene E.; Bandy, Daniel; Adamson, Jennifer L.; Lee, Wendy; Cannon, Ashley; Stephan, Elizabeth A.; Stephan, Dietrich A.; Papassotiropoulos, Andreas

2008-01-01

We recently implicated a cluster of nine single nucleotide polymorphisms from seven cholesterol-related genes in the risk of Alzheimer’s disease (AD) in a European cohort, and we proposed calculating an aggregate cholesterol-related genetic score (CREGS) to characterize a person’s risk. In a separate study, we found that apolipoprotein E (APOE) ε4 gene dose, an established AD risk factor, was correlated with fluorodeoxyglucose (FDG) positron emission tomography (PET) measurements of hypometabolism in AD-affected brain regions in a cognitively normal American cohort, and we proposed using PET as a presymptomatic endophenotype to help assess putative modifiers of AD risk. Thus, the objective in the present study is to determine whether CREGS is related to PET measurements of hypometabolism in AD-affected brain regions. DNA and PET data from 141 cognitively normal late middle-aged APOE ε4 homozygotes, heterozygotes and non-carriers were analyzed to evaluate the relationship between CREGS and regional PET measurements. Cholesterol-related genetic risk scores were associated with hypometabolism in AD-affected brain regions, even when controlling for the effects of APOE ε4 gene dose. The results support the role of cholesterol-related genes in the predisposition to AD, and support the value of neuroimaging in the presymptomatic assessment of putative modifiers of AD risk. PMID:18280754

Effect of toll-like receptor 3 agonists on the functionality and metastatic properties of breast cancer cell model.

PubMed

Alizadeh, Nastaran; Amiri, Mohammad Mehdi; Salek Moghadam, Alireza; Zarnani, Amir Hassan; Saadat, Farshid; Safavifar, Farnaz; Berahmeh, Azar; Khorramizadeh, Mohammad Reza

2013-05-15

There exists compelling evidence that Toll-like receptor 3 (TLR3) agonists can directly affect human cancer cells. The aim of this study was to investigate anti-cancer effects of TLR3 agonist in human breast cell line. We assessed potential effects of poly (A:U) on human breast cell line (MDA-MB-231) on a dose-response and time-course basis. Human breast cell line MDA-MB-231 was treated with different concentrations of poly (A:U) and lipopolysaccharide (LPS). Then, the following assays were performed on the treated cells: dose-response and time-course cytotoxicity using colorimetric method; matrix metalloproteinase-2 (MMP-2) activity using gelatin zymography method; apoptosis using annexin-v flowcytometry method; and relative expression of TLR3 and MMP-2 mRNA using reverse transcriptase polymerase chain reaction (RT-PCR) method. Following treatments, dose- response and time-course cytotoxicity using a colorimetric method, (MMP-2) activity (using gelatin zymography), apoptosis (using annexin-v flowcytometry method) assays and expression of TLR3 and MMP-2 genes (using PCR method) were performed. Cytotoxicity and flowcytometry analysis of poly (A:U) showed that poly (A:U) do not have any cytotoxic and apoptotic effects in different concentrations used. MMP-2 activity analysis showed significant decrease in higher concentrations (50 and 100 μg/ ml) between treated and untreated cells. Moreover, poly A:U treated cells demonstrated decreased expression of MMP-2 gene in higher concentrations. Collectively, our data indicated that human breast cancer cell line (MDA-MB-231) was highly responsive to poly (A:U). The antimetastatic effect of direct poly (A:U) and TLR3 interactions in MDA-MB-231 cells could provide new approaches in malignant tumor therapeutic strategy.

DNA methylation and potential multigenerational epigenetic effects linked to uranium chronic low-dose exposure in gonads of males and females rats.

PubMed

Elmhiri, G; Gloaguen, C; Grison, S; Kereselidze, D; Elie, C; Tack, K; Benderitter, M; Lestaevel, P; Legendre, A; Souidi, M

2018-01-05

An increased health problem in industrialised countries is the contemporary concern of public and scientific community as well. This has been attributed in part to accumulated environmental pollutants especially radioactive substances and the use of nuclear power plants worldwide. However, the outcome of chronic exposure to low doses of a radionuclide such as uranium remains unknown. Recently, a paradigm shift in the perception of risk of radiotoxicology has emerged through investigating the possibility of transmission of biological effects over generations, in particular by epigenetic pathways. These processes are known for their crucial roles associated with the development of several diseases. The current work investigates the epigenetic effect of chronic exposure to low doses of uranium and its inheritance across generations. Materials and Methods To test this proposition, a rodent multigenerational model, males and females, were exposed to a non-toxic concentration of uranium (40mgL -1 drinking water) for nine months. The uranium effects on were evaluated over three generations (F0, F1 and F2) by analysing the DNA methylation profile and DNMT genes expression in ovaries and testes tissues. Here we report a significant hypermethylation of testes DNA (p <0.005) whereas ovaries showed hypomethylated DNA (p <0.005). Interestingly, this DNA methylation profile was significantly maintained across generations F0, F1 and F2. Furthermore, qPCR results of both tissues imply a significant change in the expression of DNA methyltransferase genes (DNMT 1 and DNMT3a/b) as well. Altogether, our work demonstrates for the first time a sex-dependance and inheritance of epigenetic marks, DNA methylation, as a biological response to the exposure to low doses of uranium. However, it is not clear which type of reproductive cell type is more responsive in this context. Copyright © 2017 Elsevier B.V. All rights reserved.

Cytotoxicity and genotoxicity of polyethylenimine and nickel chloride in red sea bream ( Pagrosomus major) fin cell line RSBF

NASA Astrophysics Data System (ADS)

Guo, Hua-Rong; Zhang, Shi-Cui

2002-12-01

A continuous marine fish cell line RSBF (i. c. Red Sea Bream Fin) was utilized to screen the cytotoxicity and genotoxicity of polyethylenimine (PEI) and nickel chloride (NiCl2) in this study on the deleterious effects of aquatic genotoxins on fish. At the 0.01 to 1 μg/ml concentration tested, PEI had acute toxicity to the treated RSBF cells (IC50=1.12, 0.92, 0.88 and 0.64 μg/ml PEI for time 0 h, 24 h, 48 h and 72 h after treatment, respectively) and markedly inhibited their proliferation in a dose-dependent manner. At the 0.001 to 5 μmol/L concentration tested, NiCl2 posed no acute toxicity but significantly stimulated their growth (107% 214% of control). Random amplified polymorphic DNA (RAPD) technique was used to detect the genotoxic effects of PEI and NiCl2 by comparing the RAPD banding patterns of the control and treated cells. RAPD analysis indicated that at the concentrations tested, PEI was more genotoxic than NiCl2 to RSBF cells; that there was a slight dose-dependent response in the genotoxic effect of PEI but not NiCl2; and that RAPD technique might provide a sensitive, non-specific genotoxic endpoint. And the potent cytotoxicity and genotoxicity of PEI on fish cells showed that we should be cautious in utilizing it as gene, vector in fish gene transfer and human gene therapy.

Effects of 2,4,6-trinitrotoluene (TNT) on phase I and phase II biotransformation enzymes in European eel Anguilla anguilla (Linnaeus, 1758).

PubMed

Della Torre, Camilla; Corsi, Ilaria; Arukwe, Augustine; Alcaro, Luigi; Amato, Ezio; Focardi, Silvano

2008-07-01

The aim of this study was to investigate effects of the explosive 2,4,6-trinitrotoluene (TNT) on liver drug metabolizing genes and enzymes in the European eel Anguilla anguilla as a model fish species. Eels were exposed in vivo for 6h and 24h to 0.5, 1 and 2.5mg/L nominal concentrations of TNT. Expression of CYP1A, glutathione-S-transferase (pi-class; GST) and uridine-diphosphate glucuronosyltransferase (1-family) (UDPGT) genes was investigated by RT-PCR, and 7-ethoxy- and 7-methoxyresorufin-O-dealkylases (EROD, MROD), NADPH cyt c reductase (NADPH red), UDPGT and GST enzyme activities were measured by biochemical assays. An in vitro study was also performed, measuring only EROD activity. TNT exposure produced no modulation of CYP1A transcript expression while a significant inhibition of EROD enzyme activity was observed and confirmed in vitro. UDPGT transcript increased dose-dependently only at 6h while the UDPGT activity tended to increase dose-dependently at 24h. GST gene expression increased after 24h and significant increases of GST activity were observed both at 6 and 24h only at the highest TNT concentration. An increase of NADPH red activity was observed at 24h. Our results seem to indicate an inhibitory effect of TNT on CYP1A-dependent catalytic activities and a possible involvement of phase II enzymes as well as NADPH red in TNT metabolism in eels.

Expression of β-nerve growth factor and homeobox A10 in experimental cryptorchidism treated with exogenous nerve growth factor.

PubMed

Xian, Hua; Xian, Yun; Liu, Lili; Wang, Yongjun; He, Jianghong; Huang, Jianfei

2015-04-01

With the exception of standard inguinal orchidopexy, treatment of cryptorchidism with human chorionic gonadotropin has been performed for several years; however, its side effects have limited its application. The β‑nerve growth factor (NGF) and homeobox A10 (HoxA10) genes are closely associated with the development of the testes. To the best of our knowledge, whether exogenous NGF alters the endogenous levels of NGF and HoxA10 in cryptorchidism in rats remains to be elucidated. The aim of the present study was to evaluate the gene and protein expression of NGF and HoxA10 in experimental cryptorchidism following treatment with exogenous NGF. A unilateral mechanical cryptorchidism model in Sprague-Dawley rats was established and different concentrations of exogenous NGF were administered to observe the effects of NGF on cryptorchidism. Changes in the gene and protein expression levels of NGF and HoxA10 in the cryptorchid tissues of each group were identified using one step reverse transcription-quantitative polymerase chain reaction, in situ hybridization with digoxigenin‑labeled‑β‑NGF RNA probes, immunofluorescence and immunohistochemistry, respectively. The expression levels of NGF and HoxA10 were markedly higher in the group treated with a high dose of exogenous NGF compared with the group treated with a low dose of exogenous NGF and the group treated with human chorionic gonadotropin. These results confirmed the potential therapeutic effect of exogenous NGF in human cryptorchidism.

A biotin-triggered genetic switch in mammalian cells and mice.

PubMed

Weber, Wilfried; Lienhart, Cédric; Baba, Marie Daoud-El; Fussenegger, Martin

2009-03-01

Adjustable and reversible transgene expression systems enabling precise control of metabolic pathways and tunable production of specific target proteins have been essential for conditional reprogramming of mammalian cells to achieve progress in basic and applied bioengineering disciplines. Most of the currently available transgene control modalities have been designed to be responsive to clinically licensed pharmacologically active drugs which were expected to prevail in future clinical trials yet raised concerns about side effects when administered long term at subclinical doses. We have chosen vitamin H, also known as biotin, to control target gene transcription in mammalian cells in a potentially side effect-free manner. BirA, the Escherichia coli repressor of the biotin biosynthesis operon, was fused to the Herpes simplex transactivation domain to generate a biotin-dependent transactivator(BIT), which, in the presence of biotin, binds and activates chimeric target promoters (P(BIT)) harboring BirA-specific operator sites 5' of a minimal promoter. Biotin-inducible transgene expression was functional in a variety of rodent, monkey and human cell lines, showed excellent adjustability and reversibility in transgenic Chinese hamster ovary cell lines, provided precise product gene control in standard bioreactor cultures and enabled dose-dependent vitamin H control of a human glycoprotein in mice. The combination of a side effect-free inducer, precise and reversible transcription tunability and broad functionality in different cell types as well as in entire animals represents a unique asset for the use of biotin-inducible transgene control in future gene therapy, tissue engineering and biopharmaceutical manufacturing scenarios.

Differentially expressed genes and pathways induced by organophosphates in human neuroblastoma cells.

PubMed

Li, Tianwei; Zhao, Hongtao; Hung, Guo-Chiuan; Han, Jing; Tsai, Shien; Li, Bingjie; Zhang, Jing; Puri, Raj K; Lo, Shyh-Ching

2012-12-01

Organophosphates (OPs) are toxic chemicals commonly used as pesticides and herbicides. Some OPs are highly toxic to humans and have been used in warfare and terrorist attacks. In order to elucidate the molecular mechanisms of injury caused by OPs, the differentially expressed genes were analyzed in human SK-N-SH neuroblastoma cells induced by three OPs. The SK-N-SH cells were treated with one of the three OPs, chlorpyrifos, dichlorvos or methamidophos at LC20 (high-dose), the concentration causing 20% cell death, as well as 1/20 of LC20 (low-dose), a sub-lethal concentration with no detectable cell death, for 24 h. The genome-wide gene changes were identified by Agilent Microarray System, and analyzed by microarray analysis tools. The analysis revealed neuroblastoma cells treated with the high doses of all three OPs markedly activated cell apoptosis and inhibited cell growth and proliferation genes, which would most likely lead to the process of cell death. Interestingly, the analysis also revealed significant decrease in expressions of many genes in a specific spliceosome pathway in cells treated with the low doses of all three different OPs. The change of spliceosome pathway may represent an important mechanism of injury in neuronal cells exposed to low doses of various OPs. In addition to unraveling a potentially different form of OP pathogenesis, this finding could provide a new diagnostic marker in assessing OP-associated injury in cells or tissues. In addition, these results could also contribute to the development of new prevention and/or therapeutic regimens against OP toxicity.

Low-dose strontium stimulates osteogenesis but high-dose doses cause apoptosis in human adipose-derived stem cells via regulation of the ERK1/2 signaling pathway.

PubMed

Aimaiti, Abudousaimi; Maimaitiyiming, Asihaerjiang; Boyong, Xu; Aji, Kaisaier; Li, Cao; Cui, Lei

2017-12-19

Strontium is a widely used anti-osteoporotic agent due to its dual effects on inhibiting bone resorption and stimulating bone formation. Thus, we studied the dose response of strontium on osteo-inductive efficiency in human adipose-derived stem cells (hASCs). Qualitative alkaline phosphatase (ALP) staining, quantitative ALP activity, Alizarin Red staining, real-time polymerase chain reaction and Western blot were used to investigate the in vitro effects of a range of strontium concentrations on hASC osteogenesis and associated signaling pathways. In vitro work revealed that strontium (25-500 μM) promoted osteogenic differentiation of hASCs according to ALP activity, extracellular calcium deposition, and expression of osteogenic genes such as runt-related transcription factor 2, ALP, collagen-1, and osteocalcin. However, osteogenic differentiation of hASCs was significantly inhibited with higher doses of strontium (1000-3000 μM). These latter doses of strontium promoted apoptosis, and phosphorylation of ERK1/2 signaling was increased and accompanied by the downregulation of Bcl-2 and increased phosphorylation of BAX. The inhibition of ERK1/2 decreased apoptosis in hASCs. Lower concentrations of strontium facilitate osteogenic differentiation of hASCs up to a point; higher doses cause apoptosis of hASCs, with activation of the ERK1/2 signaling pathway contributing to this process.

Successful adenovirus-mediated wild-type p53 gene transfer in patients with bladder cancer by intravesical vector instillation.

PubMed

Kuball, Jürgen; Wen, Shu Fen; Leissner, Joachim; Atkins, Derek; Meinhardt, Patricia; Quijano, Erlinda; Engler, Heidrun; Hutchins, Beth; Maneval, Daniel C; Grace, Michael J; Fritz, Mary Ann; Störkel, Stefan; Thüroff, Joachim W; Huber, Christoph; Schuler, Martin

2002-02-15

To study safety, feasibility, and biologic activity of adenovirus-mediated p53 gene transfer in patients with bladder cancer. Twelve patients with histologically confirmed bladder cancer scheduled for cystectomy were treated on day 1 with a single intratumoral injection of SCH 58500 (rAd/p53) at cystoscopy at one dose level (7.5 x 10(11) particles) or a single intravesical instillation of SCH 58500 with a transduction-enhancing agent (Big CHAP) at three dose levels (7.5 x 10(11) to 7.5 x 10(13) particles). Cystectomies were performed in 11 patients on day 3, and transgene expression, vector distribution, and biologic markers of transgene activity were assessed by molecular and immunohistochemical methods in tumors and normal bladder samples. Specific transgene expression was detected in tissues from seven of eight assessable patients treated with intravesical instillation of SCH 58500 but in none of three assessable patients treated with intratumoral injection of SCH 58500. Induction of RNA and protein expression of the p53 target gene p21/WAF1 was demonstrated in samples from patients treated with SCH 58500 instillation at higher dose levels. Distribution studies after intravesical instillation of SCH 58500 revealed both high transduction efficacy and vector penetration throughout the whole urothelium and into submucosal tumor cells. No dose-limiting toxicity was observed, and side effects were local and of transient nature. Intravesical instillation of SCH 58500 combined with a transduction-enhancing agent is safe, feasible, and biologically active in patients with bladder cancer. Studies to evaluate the clinical efficacy of this treatment in patients with localized high-risk bladder cancer are warranted.

Low-dose exposure to bisphenols A, F and S of human primary adipocyte impacts coding and non-coding RNA profiles

PubMed Central

Leloire, Audrey; Dhennin, Véronique; Coumoul, Xavier; Yengo, Loïc; Froguel, Philippe

2017-01-01

Bisphenol A (BPA) exposure has been suspected to be associated with deleterious effects on health including obesity and metabolically-linked diseases. Although bisphenols F (BPF) and S (BPS) are BPA structural analogs commonly used in many marketed products as a replacement for BPA, only sparse toxicological data are available yet. Our objective was to comprehensively characterize bisphenols gene targets in a human primary adipocyte model, in order to determine whether they may induce cellular dysfunction, using chronic exposure at two concentrations: a “low-dose” similar to the dose usually encountered in human biological fluids and a higher dose. Therefore, BPA, BPF and BPS have been added at 10 nM or 10 μM during the differentiation of human primary adipocytes from subcutaneous fat of three non-diabetic Caucasian female patients. Gene expression (mRNA/lncRNA) arrays and microRNA arrays, have been used to assess coding and non-coding RNA changes. We detected significantly deregulated mRNA/lncRNA and miRNA at low and high doses. Enrichment in “cancer” and “organismal injury and abnormalities” related pathways was found in response to the three products. Some long intergenic non-coding RNAs and small nucleolar RNAs were differentially expressed suggesting that bisphenols may also activate multiple cellular processes and epigenetic modifications. The analysis of upstream regulators of deregulated genes highlighted hormones or hormone-like chemicals suggesting that BPS and BPF can be suspected to interfere, just like BPA, with hormonal regulation and have to be considered as endocrine disruptors. All these results suggest that as BPA, its substitutes BPS and BPF should be used with the same restrictions. PMID:28628672

Leptin stimulates bone formation in ob/ob mice at doses having minimal impact on energy metabolism.

PubMed

Philbrick, Kenneth A; Wong, Carmen P; Branscum, Adam J; Turner, Russell T; Iwaniec, Urszula T

2017-03-01

Leptin, the protein product of the ob gene, is essential for normal bone growth, maturation and turnover. Peripheral actions of leptin occur at lower serum levels of the hormone than central actions because entry of leptin into the central nervous system (CNS) is limited due to its saturable transport across the blood-brain barrier (BBB). We performed a study in mice to model the impact of leptin production associated with different levels of adiposity on bone formation and compared the response with well-established centrally mediated actions of the hormone on energy metabolism. Leptin was infused (0, 4, 12, 40, 140 or 400 ng/h) for 12 days into 6-week-old female ob/ob mice (n = 8/group) using sc-implanted osmotic pumps. Treatment resulted in a dose-associated increase in serum leptin. Bone formation parameters were increased at EC 50 infusion rates of 7-17 ng/h, whereas higher levels (EC 50 , 40-80 ng/h) were required to similarly influence indices of energy metabolism. We then analyzed gene expression in tibia and hypothalamus at dose rates of 0, 12 and 140 ng/h; the latter dose resulted in serum leptin levels similar to WT mice. Infusion with 12 ng/h leptin increased the expression of genes associated with Jak/Stat signaling and bone formation in tibia with minimal effect on Jak/Stat signaling and neurotransmitters in hypothalamus. The results suggest that leptin acts peripherally to couple bone acquisition to energy availability and that limited transport across the BBB insures that the growth-promoting actions of peripheral leptin are not curtailed by the hormone's CNS-mediated anorexigenic actions. © 2017 Society for Endocrinology.

UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B☆

PubMed Central

Yang, Kuan; Boswell, Mikki; Walter, Dylan J.; Downs, Kevin P.; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L.; Walter, Ronald B.

2014-01-01

Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adj < 0.05) were identified as responsive to UVB. The molecular genetic response of Xiphophorus skin to UVB exposure permitted assessment of; (1) the basal expression level of each transcript for each skin sample, (2) the changes in expression levels for each gene in the transcriptome upon exposure to increasing doses of UVB, and (3) clusters of genes that exhibit similar patterns of change in expression upon UVB exposure. These data provide a foundation for understanding the molecular genetic response of fish skin to UVB exposure. PMID:24556253

Ultra Low-Dose Radiation: Stress Responses and Impacts Using Rice as a Grass Model

PubMed Central

Rakwal, Randeep; Agrawal, Ganesh Kumar; Shibato, Junko; Imanaka, Tetsuji; Fukutani, Satoshi; Tamogami, Shigeru; Endo, Satoru; Sahoo, Sarata Kumar; Masuo, Yoshinori; Kimura, Shinzo

2009-01-01

We report molecular changes in leaves of rice plants (Oryza sativa L. - reference crop plant and grass model) exposed to ultra low-dose ionizing radiation, first using contaminated soil from the exclusion zone around Chernobyl reactor site. Results revealed induction of stress-related marker genes (Northern blot) and secondary metabolites (LC-MS/MS) in irradiated leaf segments over appropriate control. Second, employing the same in vitro model system, we replicated results of the first experiment using in-house fabricated sources of ultra low-dose gamma (γ) rays and selected marker genes by RT-PCR. Results suggest the usefulness of the rice model in studying ultra low-dose radiation response/s. PMID:19399245

Prodrugs for Gene-Directed Enzyme-Prodrug Therapy (Suicide Gene Therapy)

PubMed Central

2003-01-01

This review focuses on the prodrugs used in suicide gene therapy. These prodrugs need to satisfy a number of criteria. They must be efficient and selective substrates for the activating enzyme, and be metabolized to potent cytotoxins preferably able to kill cells at all stages of the cell cycle. Both prodrugs and their activated species should have good distributive properties, so that the resulting bystander effects can maximize the effectiveness of the therapy, since gene transduction efficiencies are generally low. A total of 42 prodrugs explored for use in suicide gene therapy with 12 different enzymes are discussed, particularly in terms of their physiocochemical properties. An important parameter in determining bystander effects generated by passive diffusion is the lipophilicity of the activated form, a property conveniently compared by diffusion coefficients (log P for nonionizable compounds and log D7 for compounds containing an ionizable centre). Many of the early antimetabolite-based prodrugs provide very polar activated forms that have limited abilities to diffuse across cell membranes, and rely on gap junctions between cells for their bystander effects. Several later studies have shown that more lipophilic, neutral compounds have superior diffusion-based bystander effects. Prodrugs of DNA alkylating agents, that are less cell cycle-specific than antimetabolites and more effective against noncycling tumor cells, appear in general to be more active prodrugs, requiring less prolonged dosing schedules to be effective. It is expected that continued studies to optimize the bystander effects and other properties of prodrugs and the activated species they generate will contribute to improvements in the effectiveness of suicide gene therapy. PMID:12686722