Extremely low-frequency electromagnetic fields cause DNA strand breaks in normal cells

PubMed Central

2014-01-01

Background Extremely low frequency electromagnetic fields aren’t considered as a real carcinogenic agent despite the fact that some studies have showed impairment of the DNA integrity in different cells lines. The aim of this study was evaluation of the late effects of a 100 Hz and 5.6 mT electromagnetic field, applied continuously or discontinuously, on the DNA integrity of Vero cells assessed by alkaline Comet assay and by cell cycle analysis. Normal Vero cells were exposed to extremely low frequency electromagnetic fields (100 Hz, 5.6 mT) for 45 minutes. The Comet assay and cell cycle analysis were performed 48 hours after the treatment. Results Exposed samples presented an increase of the number of cells with high damaged DNA as compared with non-exposed cells. Quantitative evaluation of the comet assay showed a significantly (<0.001) increase of the tail lengths, of the quantity of DNA in tail and of Olive tail moments, respectively. Cell cycle analysis showed an increase of the frequency of the cells in S phase, proving the occurrence of single strand breaks. The most probable mechanism of induction of the registered effects is the production of different types of reactive oxygen species. Conclusions The analysis of the registered comet indices and of cell cycle showed that extremely low frequency electromagnetic field of 100 Hz and 5.6 mT had a genotoxic impact on Vero cells. PMID:24401758

Comparative analysis of the surface exposed proteome of two canine osteosarcoma cell lines and normal canine osteoblasts

PubMed Central

2013-01-01

Background Osteosarcoma (OSA) is the most common primary bone tumor of dogs and carries a poor prognosis despite aggressive treatment. An improved understanding of the biology of OSA is critically needed to allow for development of novel diagnostic, prognostic, and therapeutic tools. The surface-exposed proteome (SEP) of a cancerous cell includes a multifarious array of proteins critical to cellular processes such as proliferation, migration, adhesion, and inter-cellular communication. The specific aim of this study was to define a SEP profile of two validated canine OSA cell lines and a normal canine osteoblast cell line utilizing a biotinylation/streptavidin system to selectively label, purify, and identify surface-exposed proteins by mass spectrometry (MS) analysis. Additionally, we sought to validate a subset of our MS-based observations via quantitative real-time PCR, Western blot and semi-quantitative immunocytochemistry. Our hypothesis was that MS would detect differences in the SEP composition between the OSA and the normal osteoblast cells. Results Shotgun MS identified 133 putative surface proteins when output from all samples were combined, with good consistency between biological replicates. Eleven of the MS-detected proteins underwent analysis of gene expression by PCR, all of which were actively transcribed, but varied in expression level. Western blot of whole cell lysates from all three cell lines was effective for Thrombospondin-1, CYR61 and CD44, and indicated that all three proteins were present in each cell line. Semi-quantitative immunofluorescence indicated that CD44 was expressed at much higher levels on the surface of the OSA than the normal osteoblast cell lines. Conclusions The results of the present study identified numerous differences, and similarities, in the SEP of canine OSA cell lines and normal canine osteoblasts. The PCR, Western blot, and immunocytochemistry results, for the subset of proteins evaluated, were generally supportive of the mass spectrometry data. These methods may be applied to other cell lines, or other biological materials, to highlight unique and previously unrecognized differences between samples. While this study yielded data that may prove useful for OSA researchers and clinicians, further refinements of the described techniques are expected to yield greater accuracy and produce a more thorough SEP analysis. PMID:23758893

Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

NASA Technical Reports Server (NTRS)

Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

2011-01-01

Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT cells and misrejoined breaks increased in both cell lines. The present study suggests that AT cells begin to rejoin breaks when a certain number of breaks are accumulated and an increased number of exchanges were observed in G0 AT cells, which is similar situation after high-dose-rate irradiation.

Ultraviolet B irradiation induces expansion of intraepithelial tumor cells in a tissue model of early cancer progression.

PubMed

Mudgil, Adarsh V; Segal, Nadav; Andriani, Frank; Wang, Youai; Fusenig, Norbert E; Garlick, Jonathan A

2003-07-01

Ultraviolet B irradiation is thought to enable skin cancer progression as clones of genetically damaged keratinocytes escape apoptosis and expand at the expense of adjacent normal cells. Mechanisms through which potentially malignant cells in human skin undergo clonal expansion, however, are not well understood. The goal of this study was to characterize the role of ultraviolet B irradiation on the intraepithelial expansion of early stage human tumor cells in organotypic skin cultures. To accomplish this, we have studied the effect of ultraviolet B irradiation on organotypic cultures that were fabricated by mixing normal human keratinocytes with beta-galactosidase-marked, intraepithelial tumor cells (HaCaT-ras, clone II-4), which bear mutations in both p53 alleles and harbor an activated H-ras oncogene. We found that when organotypic mixtures were exposed to an ultraviolet B dose of 50 mJ per cm2, intraepithelial tumor cells underwent a significant degree of proliferative expansion compared to nonirradiated cultures. To understand this response, organotypic cultures of nor-mal keratinocytes were exposed to ultraviolet B and showed a dose-dependent increase in numbers of sunburn cells and TUNEL-positive cells although their proliferation was suppressed. In contrast, neither the apoptotic nor the proliferative response of II-4 cells was altered by ultraviolet B in organotypic cultures. The differential response of these cell types suggested that II-4 cells were resistant to ultraviolet-B-induced alterations, which allowed these intraepithelial tumor cells to gain a selective growth and survival advantage relative to neighboring normal cells. These findings demonstrate that ultraviolet B exposure can induce the intraepithelial expansion of apoptosis-resistant, p53-mutant, and ras-activated keratinocytes, suggesting that this agent can act to promote the early stages of epithelial carcinogenesis.

Normalization of Tumor Microenvironment by Neem Leaf Glycoprotein Potentiates Effector T Cell Functions and Therapeutically Intervenes in the Growth of Mouse Sarcoma

PubMed Central

Barik, Subhasis; Banerjee, Saptak; Mallick, Atanu; Goswami, Kuntal Kanti; Roy, Soumyabrata; Bose, Anamika; Baral, Rathindranath

2013-01-01

We have observed restriction of the murine sarcoma growth by therapeutic intervention of neem leaf glycoprotein (NLGP). In order to evaluate the mechanism of tumor growth restriction, here, we have analyzed tumor microenvironment (TME) from sarcoma bearing mice with NLGP therapy (NLGP-TME, in comparison to PBS-TME). Analysis of cytokine milieu within TME revealed IL-10, TGFβ, IL-6 rich type 2 characters was switched to type 1 microenvironment with dominance of IFNγ secretion within NLGP-TME. Proportion of CD8+ T cells was increased within NLGP-TME and these T cells were protected from TME-induced anergy by NLGP, as indicated by higher expression of pNFAT and inhibit related downstream signaling. Moreover, low expression of FasR+ cells within CD8+ T cell population denotes prevention from activation induced cell death. Using CFSE as a probe, better migration of T cells was noted within TME from NLGP treated mice than PBS cohort. CD8+ T cells isolated from NLGP-TME exhibited greater cytotoxicity to sarcoma cells in vitro and these cells show higher expression of cytotoxicity related molecules, perforin and granzyme B. Adoptive transfer of NLGP-TME exposed T cells, but not PBS-TME exposed cells in mice, is able to significantly inhibit the growth of sarcoma in vivo. Such tumor growth inhibition by NLGP-TME exposed T cells was not observed when mice were depleted for CD8+ T cells. Accumulated evidences strongly suggest NLGP mediated normalization of TME allows T cells to perform optimally to inhibit the tumor growth. PMID:23785504

Absence of 60-Hz, 0.1-mT magnetic field-induced changes in oncogene transcription rates or levels in CEM-CM3 cells.

PubMed

Jahreis, G P; Johnson, P G; Zhao, Y L; Hui, S W

1998-12-22

Our objective was to assess the reproducibility of the 60-Hz magnetic field-induced, time-dependent transcription changes of c-fos, c-jun and c-myc oncogenes in CEM-CM3 cells reported by Phillips et al. (Biochim. Biophys. Acta, 1132 (1992) 140-144). Cells were exposed to a 60-Hz magnetic field (MF) at 0.1 mT (rms), generated by a pair of Helmholtz coils energized in a reinforcing (MF) mode, or to a null magnetic field when the coils were energized in a bucking (sham) mode. After MF or sham exposure for 15, 30, 60 or 120 min, nuclei and cytoplasmic RNA were extracted. Transcription rates were measured by a nuclear run-on assay, and values were normalized against either their zero-time exposure values, or against those of the c-G3PDH (housekeeping) gene at the same time points. There was no significant difference, at P=0.05, detected between MF and either sham-exposed or control cells at any time point. Transcript levels of the oncogenes were measured by Northern analysis and normalized as above. No significant difference (P=0.05) in transcript levels between MF and either sham-exposed or control cells was detected.

Mechanisms for the development of esophageal atresia.

PubMed

Orford, J; Manglick, P; Cass, D T; Tam, P P

2001-07-01

There is no universally accepted theory to explain esophageal embryology and the abnormal development that produces esophageal atresia. The impact of Adriamycin administration on the pathogenesis of esophageal atresia was studied in the rat model of VATER association, from embryonic day (ED) 10 to ED 13. Tissues in the ED10 Adriamycin-exposed embryos displayed less cell proliferation as shown by the reduced population of MIB-5-labelled cells. Cell apoptosis that is characteristic of the normal ED 12 lateral epithelial folds of the foregut (the prospective site of tracheoesophageal septation) was absent in the foregut of the Adriamycin-exposed embryo. Histologic examination of the ED 11-exposed embryo showed the presence of abnormal notochord that was stretched, split, or tethered to the foregut. This contrasts with the normal embryo in which the notochord was localized in close vicinity of the ventral part of the neural tube and separated from the foregut by ample amount of mesenchyme. The abnormal localization of the notochord was accompanied by the lack of down-regulation of the sonic hedgehog (Shh) activity in the prospective site of future tracheoesophageal separation in the exposed ED 12 embryo. The authors proposed that the ectopic location of the notochord leads to the disruption in Shh signalling that may underpin the development of esophageal atresia. Copyright 2001 by W.B. Saunders Company.

Changes in Ultrastructure and Cytoskeletal Aspects of Human Normal and Osteoarthritic Chondrocytes Exposed to Interleukin-1β and Cyclical Hydrostatic Pressure.

PubMed

Pascarelli, Nicola Antonio; Collodel, Giulia; Moretti, Elena; Cheleschi, Sara; Fioravanti, Antonella

2015-10-30

The aim of this study was to examine the ultrastructure and cytoskeletal organization in human normal and Osteoarhritic (OA) chondrocytes, exposed to interleukin-1β (IL-1β) and cyclic hydrostatic pressure (HP). Morphological examination by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed differences between normal and OA chondrocytes at the nuclear and cytoplasmic level. IL-1β (5 ng/mL) induced a decrease of the number of mitochondria and Golgi bodies and a significant increase on the percentage of cells rich in vacuolization and in marginated chromatin. Cyclical HP (1-5 MPa, 0.25 Hz, for 3 h) did not change the morphology of normal chondrocytes, but had a beneficial effect on OA chondrocytes increasing the number of organelles. Normal and OA cells subjected to IL-1β and HP recovered cytoplasmic ultrastructure. Immunofluorescence (IF) examination of normal chondrocytes showed an actin signal polarized on the apical sides of the cytoplasm, tubulin and vimentin uniformly distributed throughout cytoplasm and vinculin revealed a punctuated pattern under the plasma membrane. In OA chondrocytes, these proteins partially lost their organization. Stimulation with IL-1β caused, in both type of cells, modification in the cytoskeletal organization; HP counteracted the negative effects of IL-1β. Our results showed structural differences at nuclear, cytoplasmic and cytoskeletal level between normal and OA chondrocytes. IL-1β induced ultrastructural and cytoskeletal modifications, counteracted by a cyclical low HP.

Changes in Ultrastructure and Cytoskeletal Aspects of Human Normal and Osteoarthritic Chondrocytes Exposed to Interleukin-1β and Cyclical Hydrostatic Pressure

PubMed Central

Pascarelli, Nicola Antonio; Collodel, Giulia; Moretti, Elena; Cheleschi, Sara; Fioravanti, Antonella

2015-01-01

The aim of this study was to examine the ultrastructure and cytoskeletal organization in human normal and Osteoarhritic (OA) chondrocytes, exposed to interleukin-1β (IL-1β) and cyclic hydrostatic pressure (HP). Morphological examination by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed differences between normal and OA chondrocytes at the nuclear and cytoplasmic level. IL-1β (5 ng/mL) induced a decrease of the number of mitochondria and Golgi bodies and a significant increase on the percentage of cells rich in vacuolization and in marginated chromatin. Cyclical HP (1–5 MPa, 0.25 Hz, for 3 h) did not change the morphology of normal chondrocytes, but had a beneficial effect on OA chondrocytes increasing the number of organelles. Normal and OA cells subjected to IL-1β and HP recovered cytoplasmic ultrastructure. Immunofluorescence (IF) examination of normal chondrocytes showed an actin signal polarized on the apical sides of the cytoplasm, tubulin and vimentin uniformly distributed throughout cytoplasm and vinculin revealed a punctuated pattern under the plasma membrane. In OA chondrocytes, these proteins partially lost their organization. Stimulation with IL-1β caused, in both type of cells, modification in the cytoskeletal organization; HP counteracted the negative effects of IL-1β. Our results showed structural differences at nuclear, cytoplasmic and cytoskeletal level between normal and OA chondrocytes. IL-1β induced ultrastructural and cytoskeletal modifications, counteracted by a cyclical low HP. PMID:26528971

Detection of early changes in lung cell cytology by flow-systems analysis techniques. [Rats

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

Steinkamp, J.A.; Wilson, J.S.; Svitra, Z.V.

1980-03-01

Ongoing experiments designed to develop automated flow-analysis methods for assaying damage to pulmonary lavage cells in experimental animals exposed by inhalation to environmental pollutants are summarized. Pulmonary macrophages were characterized on their ability to phagocytize polystyrene latex fluorescent spheres. Lung cells consisting primarily of macrophages and leukocytes were analyzed for fluorescence (phagocytosis of spheres) and size using flow cytometric methods. Studies also concentrated on combining phagocytosis with other cellular parameters (DNA content, cell viability, and B-glucuronidase activity). As baseline studies are completed in normal animals, experimental animals will be exposed to gaseous and particulate environmental pollutants. (ERB

COMPARISON OF IN VITRO AND IN VIVO RESPONSES TO ARSENIC: GENE EXPRESSION PROFILING IN NORMAL HUMAN EPIDERMAL KERATINOCYTES AND HYPERKERATOSES FROM ARSENIC-EXPOSED HUMANS

EPA Science Inventory

Chronic exposure to arsenic is positively associated with skin, urinary bladder, lung, liver and kidney cancer development in humans. Elucidating the mode of action of arsenic carcinogenesis is a complicated issue as target cells are exposed to different toxic species of arsenic....

Heterogeneity in c-jun gene expression in normal and malignant cells exposed to either ionizing radiation or hydrogen peroxide

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

Collart, F.R.; Horio, M.; Huberman, E.

1995-05-01

We investigated the role of reactive oxygen intermediates and protein kinase C in the induction of expression of the c-jun gene in human ML-2 leukemic cells and normal human DET-551 fibroblasts by comparing the effects of exposure to either ionizing radiation or H{sub 2}O{sub 2} in the presence or absence of appropriate inhibitors. In these cell types, the radiation-and H{sub 2}O{sub 2}-mediated increase in c-jun mRNA levels could be prevented by pretreatment of the cells with N-acetylcysteine, and antioxidant, or H7, an inhibitor of protein kinase C and protein kinase A, but not by HA1004, a specific inhibitor of proteinmore » kinase A and G. These results suggest a role for protein kinase C and reactive oxygen intermediates in the induction of c-jun gene expression in both normal and tumor cells. We also investigated potential differences in c-jun gene expression induced by radiation or H{sub 2}O{sub 2} in normal and tumor cells by examining steady-state c-jun mRNA levels in a number of human fibroblast, leukemia, melanoma, sarcoma and carcinoma cell types. We observed heterogeneity in the steady-state level of c-jun mRNA in both the untreated normal and tumor cells and in such cells exposed to ionizing radiation or to H{sub 2}O{sub 2}. Exposure to radiation produced a varied response which ranged from little or no induction to an increase in the steady-state level of the c-jun mRNA of more than two orders of magnitude. Exposure to H{sub 2}O{sub 2} gave a pattern similar to that of ionizing radiation. The basis for the differential induction in response to these agents may be attributable to either cell lineage or genetic heterogeneity or a combination of these two parameters. 30 refs., 7 figs., 1 tab.« less

In vitro measurements of oxygen consumption rates in hTERT-RPE cells exposed to low levels of red light

NASA Astrophysics Data System (ADS)

Wigle, Jeffrey C.; Castellanos, Cherry C.

2016-03-01

Exposure to 2.88 J/cm2 of red light induces an adaptive response against a lethal pulse of 2.0 μm laser radiation in hTERT-RPE cells in vitro, but not in a knockdown mutant for vascular endothelial growth factor c (VEGF-C). The generally accepted initiation sequence for photobiomodulation is that absorption of red light by cytochome c oxidase (CCOX) of the electron transport chain increases the binding affinity of CCOX for O2 vs. nitric oxide (NO). This results in displacement of NO by O2 in the active site of CCOX, thereby increasing cellular respiration and intracellular ATP. We've previously reported that red-light exposure induces a small, but consistently reproducible, increase in NO levels in these cells. But the relative importance of NO and oxidative phosphorylation is unclear because little is known about the relative contributions of NO and ATP to the response. However, if NO dissociation from CCOX actually increases oxidative phosphorylation, one should see a corresponding increase in oxygen consumption. A Seahorse Extracellular Flux Analyzer was used to measure oxygen consumption rates (OCR) in normal and mutant cells as a proxy for oxidative phosphorylation. Both basal respiration and maximum respiration rates in normal cells are significantly higher than in the mutant. The normal cells have a significant amount of "excess capacity," whereas the VEGF-C(KD) have little or none. The OCR in exposed normal cells is lower than in unexposed cells when measured immediately after exposure. The exposures used for these experiments had no effect on the OCR in mutant cells.

[Effect of American Ginseng Capsule on the liver oxidative injury and the Nrf2 protein expression in rats exposed by electromagnetic radiation of frequency of cell phone].

PubMed

Luo, Ya-ping; Ma, Hui-Rong; Chen, Jing-Wei; Li, Jing-Jing; Li, Chun-xiang

2014-05-01

To observe the effect of American Ginseng Capsule (AGC) on the liver oxidative injury and the Nrf2 protein expression in the liver tissue of rats exposed by 900 MHz cell phone electromagnetic radiation. Totally 40 male SD rats were randomly divided into the normal control group, the model group, the Shuifei Jibin Capsule (SJC) group, and the AGC group,10 in each group. Rats in the normal control group were not irradiated. Rats in the rest three groups were exposed by imitated 900 MHz cellular phone for 4 h in 12 consecutive days. Meanwhile, rats in the SJC group and the AGC group were intragastrically administrated with suspension of SJC and AGC (1 mL/200 g body weight) respectively. Normal saline was administered to rats in the normal control group and the model group. The histolomorphological changes of the liver tissue were observed by HE staining. Contents of malonic dialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-PX)were detected by colorimetry. The Nrf2 protein expression of hepatocytes was detected by immunohistochemical assay and Western blot. Compared with the normal control group, hepatocyte nucleus was atrophied or partially disappeared, the contents of liver MDA and Nrf2 protein obviously increased (P <0. 05, P <0. 01); contents of liver SOD and GSH decreased (P <0. 05) in the model group. Compared with the model group, karyopyknosis was obviously attenuated and approached to the normal level in the SJC group and the AGC group. The contents of liver MDA and Nrf2 protein expression decreased (P <0. 05), and the contents of liver SOD, GSH, and GSH-PX obviously increased (P < 0.05) in the SJC group. The contents of liver MDA and the Nrf2 protein expression decreased (P < 0.05), and contents of SOD and GSH obviously increased in the AGC group (P <0.01, P <0.05). The electromagnetic radiation induced by 900 MHz cell phone could affect the expression of Nrf2 protein, induce oxidative injury, and induce abnormal morphology of liver cells. SJC and AGC could promote the morphological recovery of the liver cells. Its mechanism might be related to affecting the expression of Nrf2 protein and attenuating oxidative damage of liver cells.

Chronic electronic cigarette exposure in mice induces features of COPD in a nicotine-dependent manner

PubMed Central

Garcia-Arcos, Itsaso; Geraghty, Patrick; Baumlin, Nathalie; Campos, Michael; Dabo, Abdoulaye Jules; Jundi, Bakr; Cummins, Neville; Eden, Edward; Grosche, Astrid; Salathe, Matthias; Foronjy, Robert

2016-01-01

Background The use of electronic (e)-cigarettes is increasing rapidly, but their lung health effects are not established. Clinical studies examining the potential long-term impact of e-cigarette use on lung health will take decades. To address this gap in knowledge, this study investigated the effects of exposure to aerosolised nicotine-free and nicotine-containing e-cigarette fluid on mouse lungs and normal human airway epithelial cells. Methods Mice were exposed to aerosolised phosphate-buffered saline, nicotine-free or nicotine-containing e-cigarette solution, 1-hour daily for 4 months. Normal human bronchial epithelial (NHBE) cells cultured at an air-liquid interface were exposed to e-cigarette vapours or nicotine solutions using a Vitrocell smoke exposure robot. Results Inhalation of nicotine-containing e-cigarettes increased airway hyper-reactivity, distal airspace enlargement, mucin production, cytokine and protease expression. Exposure to nicotine-free e-cigarettes did not affect these lung parameters. NHBE cells exposed to nicotine-containing e-cigarette vapour showed impaired ciliary beat frequency, airway surface liquid volume, cystic fibrosis transmembrane regulator and ATP-stimulated K+ ion conductance and decreased expression of FOXJ1 and KCNMA1. Exposure of NHBE cells to nicotine for 5 days increased interleukin (IL)-6 and IL-8 secretion. Conclusions Exposure to inhaled nicotine-containing e-cigarette fluids triggered effects normally associated with the development of COPD including cytokine expression, airway hyper-reactivity and lung tissue destruction. These effects were nicotine-dependent both in the mouse lung and in human airway cells, suggesting that inhaled nicotine contributes to airway and lung disease in addition to its addictive properties. Thus, these findings highlight the potential dangers of nicotine inhalation during e-cigarette use. PMID:27558745

GENE EXPRESSION PROFILING OF NORMAL HUMAN BRONCHIAL EPITHELIAL CELLS EXPOSED TO TRIVALENT ARSENICALS AND DIMETHYLTHIOARSINIC ACID

EPA Science Inventory

Lung is a major target for arsenic carcinogenesis in humans. However, the carcinogenic mode of action of arsenicals is unknown. We investigated, in human bronchial epithelial (BEAS2B) cells, the effects of inorganic arsenic (iAsIII), monomethylarsonous acid (MMAIII), dimethylarsi...

ULTRAFINE CARBON PARTICLES INDUCE INTERLEUKIN-8 GENE TRANSCRIPTION AND P38 MAPK ACTIVATION IN NORMAL BRONCHIAL EPITHELIAL CELLS

EPA Science Inventory

Epidemiological studies suggest that ultrafine particles contribute to particulate matter-induced adverse health effects. Interleukin (IL)-8 is an important proinflammatory cytokine in the human lung that is induced in respiratory cells exposed to a variety of environmental insul...

Di-(2-ethylhexyl) phthalate could disrupt the insulin signaling pathway in liver of SD rats and L02 cells via PPARγ

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

Zhang, Wang; Shen, Xin-Yue; Zhang, Wen-wen

Di-(2-ethylhexyl)-phthalate (DEHP), a ubiquitous industrial pollutant in our daily life, has been reported to cause adverse effects on glucose homeostasis and insulin sensitivity in epidemiological studies previously. Recently, it has been reported to be an endocrine disrupter and ligand to peroxisome proliferator activated receptor, which could influence the homeostasis of liver metabolic systems and contribute to the development of type-2 diabetes. However, the potential mechanisms are not known yet. This study was designed to solve these problems with male SD rats and normal human hepatocyte line, L02 cells, exposed to DEHP for toxicological experiments. Adult male SD rats were dividedmore » into four groups, normal group fed with regular diets and three DEHP-treated groups (dissolved in olive oil at doses of 0.05, 5 and 500 mg/kg body weight, respectively, once daily through gastric intubations for 15 weeks). L02 cells were divided into 6 groups, normal group with 5, 10, 25, 50, and 100 μmol/l DEHP groups. DEHP-exposed rats exhibited significant liver damage, glucose tolerance, and insulin tolerance along with reduced expression of insulin receptor and GLUT4 proteins in the liver tissues. The results of in vitro experiments could determine that the DEHP-induced activation of peroxisome proliferator activated receptor γ (PPARγ) played a key role in the production of oxidative stress and down-regulated expression of insulin receptor and GLUT4 proteins in L02 cells. This conclusion could be supported by the results of in vitro experiments, in which the cells were exposed to DEHP with GW9662 (PPARγ inhibitor). In general, these results highlight the key role of PPARγ in the process of insulin resistance induced by DEHP. - Highlights: • DEHP exacerbates insulin resistance both in liver tissues and cells. • Expression of insulin receptor and GLUT4 were altered with PPARγ. • DEHP can induce oxidative stress to disrupt the metabolic homeostasis. • The dose of exposed DEHP is closed to daily exposure by human. • Determine the key role of PPARγ to insulin resistance.« less

Inhibition of histone/lysine acetyltransferase activity kills CoCl2-treated and hypoxia-exposed gastric cancer cells and reduces their invasiveness

PubMed Central

Rath, Suvasmita; Das, Lopamudra; Kokate, Shrikant Babanrao; Ghosh, Nilabh; Dixit, Pragyesh; Rout, Niranjan; Singh, Shivaram P.; Chattopadhyay, Subhasis; Ashktorab, Hassan; Smoot, Duane T.; Swamy, Mahadeva M.; Kundu, Tapas K.; Crowe, Sheila E.; Bhattacharyya, Asima

2017-01-01

Hypoxia enhances immortality and metastatic properties of solid tumors. Deregulation of histone acetylation has been associated with several metastatic cancers but its effect on hypoxic responses of cancer cells is not known. This study aimed at understanding the effectiveness of the hydrazinocurcumin, CTK7A, an inhibitor of p300 lysine/histone acetyltransferase (KAT/HAT) activity, in inducing apoptosis of gastric cancer cells (GCCs) exposed to cobalt chloride (CoCl2), a hypoxia-mimetic chemical, or 1% O2. Here, we show that CTK7A-induced hydrogen peroxide (H2O2) generation in CoCl2-exposed and invasive gastric cancer cells (GCCs) leads to p38 MAPK-mediated Noxa expression and thereafter, mitochondrial apoptotic events. Noxa induction in normal immortalized gastric epithelial cells after CTK7A and hypoxia-exposure is remarkably less in comparison to similarly-treated GCCs. Moreover, hypoxia-exposed GCCs, which have acquired invasive properties, become apoptotic after CTK7A treatment to a significantly higher extent than normoxic cells. Thus, we show the potential of CTK7A in sensitizing hypoxic and metastatic GCCs to apoptosis induction. PMID:27890795

Cell Radiation Experiment System

NASA Technical Reports Server (NTRS)

Morrison, Dennis R.

2010-01-01

The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

Low Intensity and Frequency Pulsed Electromagnetic Fields Selectively Impair Breast Cancer Cell Viability

PubMed Central

Crocetti, Sara; Beyer, Christian; Schade, Grit; Egli, Marcel; Fröhlich, Jürg; Franco-Obregón, Alfredo

2013-01-01

Introduction A common drawback of many anticancer therapies is non-specificity in action of killing. We investigated the potential of ultra-low intensity and frequency pulsed electromagnetic fields (PEMFs) to kill breast cancer cells. Our criteria to accept this technology as a potentially valid therapeutic approach were: 1) cytotoxicity to breast cancer cells and; 2) that the designed fields proved innocuous to healthy cell classes that would be exposed to the PEMFs during clinical treatment. Methods MCF7 breast cancer cells and their normal counterparts, MCF10 cells, were exposed to PEMFs and cytotoxic indices measured in order to design PEMF paradigms that best kill breast cancer cells. The PEMF parameters tested were: 1) frequencies ranging from 20 to 50 Hz; 2) intensities ranging from 2 mT to 5 mT and; 3) exposure durations ranging from 30 to 90 minutes per day for up to three days to determine the optimum parameters for selective cancer cell killing. Results We observed a discrete window of vulnerability of MCF7 cells to PEMFs of 20 Hz frequency, 3 mT magnitude and exposure duration of 60 minutes per day. The cell damage accrued in response to PEMFs increased with time and gained significance after three days of consecutive daily exposure. By contrast, the PEMFs parameters determined to be most cytotoxic to breast cancer MCF-7 cells were not damaging to normal MCF-10 cells. Conclusion Based on our data it appears that PEMF-based anticancer strategies may represent a new therapeutic approach to treat breast cancer without affecting normal tissues in a manner that is non-invasive and can be potentially combined with existing anti-cancer treatments. PMID:24039828

Continuous exposure to low amplitude extremely low frequency electrical fields characterizing the vascular streaming potential alters elastin accumulation in vascular smooth muscle cells.

PubMed

Bergethon, Peter R; Kindler, Dean D; Hallock, Kevin; Blease, Susan; Toselli, Paul

2013-07-01

In normal development and pathology, the vascular system depends on complex interactions between cellular elements, biochemical molecules, and physical forces. The electrokinetic vascular streaming potential (EVSP) is an endogenous extremely low frequency (ELF) electrical field resulting from blood flowing past the vessel wall. While generally unrecognized, it is a ubiquitous electrical biophysical force to which the vascular tree is exposed. Extracellular matrix elastin plays a central role in normal blood vessel function and in the development of atherosclerosis. It was hypothesized that ELF fields of low amplitude would alter elastin accumulation, supporting a link between the EVSP and the biology of vascular smooth muscle cells. Neonatal rat aortic smooth muscle cell cultures were exposed chronically to electrical fields characteristic of the EVSP. Extracellular protein accumulation, DNA content, and electron microscopic (EM) evaluation were performed after 2 weeks of exposure. Stimulated cultures showed no significant change in cellular proliferation as measured by the DNA concentration. The per-DNA normalized protein in the extracellular matrix was unchanged while extracellular elastin accumulation decreased 38% on average. EM analysis showed that the stimulated cells had a 2.85-fold increase in mitochondrial number. These results support the formulation that ELF fields are a potential factor in both normal vessel biology and in the pathogenesis of atherosclerotic diseases including heart disease, stroke, and peripheral vascular disease. Copyright © 2013 Wiley Periodicals, Inc.

Suppression of noise-induced hyperactivity in the dorsal cochlear nucleus following application of the cholinergic agonist, carbachol

PubMed Central

Manzoor, N.F.; Chen, G.; Kaltenbach, J.A.

2013-01-01

Increased spontaneous firing (hyperactivity) is induced in fusiform cells of the dorsal cochlear nucleus (DCN) following intense sound exposure and is implicated as a possible neural correlate of noise-induced tinnitus. Previous studies have shown that in normal hearing animals, fusiform cell activity can be modulated by activation of parallel fibers, which represent the axons of granule cells. The modulation consists of a transient excitation followed by a more prolonged period of inhibition, presumably reflecting direct excitatory inputs to fusiform cells and an indirect inhibitory input to fusiform cells from the granule cell-cartwheel cell system. We hypothesized that since granule cells can be activated by cholinergic inputs, it might be possible to suppress tinnitus-related hyperactivity of fusiform cells using the cholinergic agonist, carbachol. To test this hypothesis, we recorded multiunit spontaneous activity in the fusiform soma layer (FSL) of the DCN in control and tone-exposed hamsters (10 kHz, 115 dB SPL, 4 h) before and after application of carbachol to the DCN surface. In both exposed and control animals, 100 µM carbachol had a transient excitatory effect on spontaneous activity followed by a rapid weakening of activity to near or below normal levels. In exposed animals, the weakening of activity was powerful enough to completely abolish the hyperactivity induced by intense sound exposure. This suppressive effect was partially reversed by application of atropine and was not associated with significant changes in neural best frequencies (BF) or BF thresholds. These findings demonstrate that noise-induced hyperactivity can be pharmacologically controlled and raise the possibility that attenuation of tinnitus may be achievable by using an agonist of the cholinergic system. PMID:23721928

Suppression of noise-induced hyperactivity in the dorsal cochlear nucleus following application of the cholinergic agonist, carbachol.

PubMed

Manzoor, N F; Chen, G; Kaltenbach, J A

2013-07-26

Increased spontaneous firing (hyperactivity) is induced in fusiform cells of the dorsal cochlear nucleus (DCN) following intense sound exposure and is implicated as a possible neural correlate of noise-induced tinnitus. Previous studies have shown that in normal hearing animals, fusiform cell activity can be modulated by activation of parallel fibers, which represent the axons of granule cells. The modulation consists of a transient excitation followed by a more prolonged period of inhibition, presumably reflecting direct excitatory inputs to fusiform cells and an indirect inhibitory input to fusiform cells from the granule cell-cartwheel cell system. We hypothesized that since granule cells can be activated by cholinergic inputs, it might be possible to suppress tinnitus-related hyperactivity of fusiform cells using the cholinergic agonist, carbachol. To test this hypothesis, we recorded multiunit spontaneous activity in the fusiform soma layer (FSL) of the DCN in control and tone-exposed hamsters (10 kHz, 115 dB SPL, 4h) before and after application of carbachol to the DCN surface. In both exposed and control animals, 100 μM carbachol had a transient excitatory effect on spontaneous activity followed by a rapid weakening of activity to near or below normal levels. In exposed animals, the weakening of activity was powerful enough to completely abolish the hyperactivity induced by intense sound exposure. This suppressive effect was partially reversed by application of atropine and was usually not associated with significant changes in neural best frequencies (BF) or BF thresholds. These findings demonstrate that noise-induced hyperactivity can be pharmacologically controlled and raise the possibility that attenuation of tinnitus may be achievable by using an agonist of the cholinergic system. Copyright © 2013 Elsevier B.V. All rights reserved.

Targeting Phosphatidylserine for Radioimmunotherapy of Breast Cancer Brain Metastasis

DTIC Science & Technology

2015-12-01

response. e. Correlate imaging findings with histological studies of vascular damage, tumor cell and endothelial cell apoptosis or necrosis and vascular ...phosphatidylserine (PS) is exposed exclusively on tumor vascular endothelium of brain metastases in mouse models. A novel PS-targeting antibody, PGN635... vascular endothelial cells in multi-focal brain metastases throughout the whole mouse brain. Vascular endothelium in normal brain tissues is negative

In vitro analysis of multistage carcinogenesis

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

Nettesheim, P.; Fitzgerald, D.J.; Kitamura, H.

1987-11-01

Several key events in the multistep process of neoplastic transformation of rat tracheal epithelium (RTE) are described. Whether tracheal epithelium is exposed in vivo to carcinogenic agents or whether primary tracheal epithelial cells are exposed in vitro to carcinogens, initiated stem cells can be detected soon after the exposure by their ability to grow under selective conditions in culture. These initiated stem cells differ fundamentally from normal stem cells in their response to factors normally constraining proliferation and self-renewal. Thus, disruption of inhibitory control mechanisms of stem cell replication appears to be the first event in RTE cell transformation. Whilemore » the probability of self-renewal (PSR) is clearly increased in initiated stem cells, most of the descendants derived form such stem cells differentiate and become terminal and do not express transformed characteristics. Progression from the first to the second stage of RTE cell transformation, the stage of the immortal growth variant (IGV), is characterized by loss of responsiveness to the growth-restraining effects of retinoic acid. In the third stage of neoplastic transformation, the stage during which neoplastic growth variants (NGV) appear, a growth factor receptor gene is inappropriately expressed in some of the transformants. Thus, it appears that loss of growth-restraining mechanisms may be an early event, and activation of a growth stimulatory mechanism a late event, in neoplastic transformation of RTE cells.« less

Phenotypical changes in a differentiating immortalized bronchial epithelial cell line after exposure to mainstream cigarette smoke and e-cigarette vapor.

PubMed

Aufderheide, Michaela; Emura, Makito

2017-07-05

3D constructs composed of differentiated immortalized primary normal human bronchial epithelial (NHBE) cells (CL-1548) were repeatedly exposed at the air-liquid interface to non-lethal concentrations of mainstream cigarette smoke (4 cigarettes a day, 5days/week, 8 repetitions in total) and e-cigarette vapor (50 puffs a day, 5 days/week, 8 repetitions in total) to build up a permanent burden on the cells. Samples were taken after 4, 6 and 8 times of repeated smoke exposure and the cultures were investigated using histopathological methods Compared to the clean air-exposed cultures (process control) and incubator control, the aerosol-exposed cultures showed a reduction of ciliated, mucus-producing and club cells. At the end of the exposure phase, we even found metaplastic areas positive for CK13 antibody in the cultures exposed to mainstream cigarette smoke and e-liquid vapor, commonly seen in squamous cells as a marker for non-cornified squamous epithelium. The control cultures (incubator cells) showed no comparable phenotypical changes. In conclusion, our in vitro model presents a valuable tool to study the induction of phenotypical changes after exposure to hazardous airborne material. Copyright © 2017. Published by Elsevier GmbH.

Role of Hsp-70 responses in cold acclimation of HUVEC-12 cells.

PubMed

Guan, Hao; Hu, Dahai; Zhao, Zhijing; Cai, Weixia; Zhou, Qin; Yang, Ximing; Yan, Ying; Zhu, Xiongxiang

2015-01-01

Endothelial recovery is a central feature of tissues after frostbite injuries. Thermo tolerance plays an important role in protecting cells against injury after frozen and thawing. The present study aimed to quantitatively assess the injury of human umbilical vein endothelial cells HUVEC-12 after repeated low temperature. Pretreatments (HUVEC-12) cells were repeatedly exposed to cold (1°C/min decrement to -20°C). Their proliferation, death, apoptosis, and protein and mRNA expressions of HSP70 were determined. Endothelial cells after repeated cold exposures were more resistant to apoptosis and necrosis than normal cells. The expressions of HSP70 in cells after repeated cold exposures were significantly higher than in normal HUVEC-12 cells (P < 0.05). Cold acclimation may induce the expression of HSP-70 which plays a protective role in the temperature tolerance.

The effect of Nullomer-derived peptides 9R, 9S1R and 124R on the NCI-60 panel and normal cell lines.

PubMed

Alileche, Abdelkrim; Hampikian, Greg

2017-08-09

Nullomer peptides are the smallest sequences absent from databases of natural proteins. We first began compiling a list of absent 5-amino acid strings in 2006 (1). We report here the effects of Nullomer-derived peptides 9R, 9S1R and 124R on the NCI-60 panel, derived from human cancers of 9 organs (kidney, ovary, skin melanoma, lung, brain, lung, colon, prostate and the hematopoietic system), and four normal cell lines (endothelial HUVEC, skin fibroblasts BJ, colon epithelial FHC and normal prostate RWPE-1). NCI-60 cancer cell panel and four normal cell lines were cultured in vitro in RPMI1640 supplemented with 10% Hyclone fetal bovine serum and exposed for 48 h to 5 μM, 25 μM and 50 μM of peptides 9R, 9S1R and 124R. Viability was assessed by CCK-8 assay. For peptide ATP depletion effects, one cell line representing each organ in the NCI-60 panel, and four normal cell lines were exposed to 50 μM of peptides 9R, 9S1R and 124R for 3 h. The ATP content was assessed in whole cells, and their supernatants. Peptides 9S1R and 9R are respectively lethal to 95 and 81.6% of the 60 cancer cell lines tested. Control peptide 124R has no effect on the growth of these cells. Especially interesting the fact that peptides 9R and 9S1R are capable of killing drug-resistant and hormone-resistant cell lines, and even cancer stem cells. Peptides 9R and 9S1R have a broader activity spectrum than many cancer drugs in current use, can completely deplete cellular ATP within 3 h, and are less toxic to 3 of the 4 normal cell lines tested than they are to several cancers. Nullomer peptides 9R and 9S1R have a large broad lethal effect on cancer cell lines derived from nine organs represented in the NCI-60 panel. This broad activity crosses many of the categorical divisions used in the general classification of cancers: solid vs liquid cancers, drug sensitive vs drug resistant, hormone sensitive vs hormone resistant, cytokine sensitive vs cytokine non sensitive, slow growing vs rapid growing, differentiated vs dedifferentiated cancers. Furthermore peptides 9R and 9S1R are lethal to cancer stem cells and breast canrcinosarcoma.

Effects of Microwave Radiation on Humans. Monkeys Exposed to 1.25 GHZ pulsed Microwaves

DTIC Science & Technology

1992-03-13

matter. The entire retina was examined by indirect ophthalmoscopy. Photographic documentation included photomicrographs of the corneal endothelial cells...segment and retina appear normal. Photos of corneal endothelium pre and post irradiation demonstrated no change. The retinal photos also appeared normal...and photographic documentation. However, baseline fluorescein angiograms of the retina and iris were also included. It was determined that baseline

High-LET Radiation Induced Chromosome Aberrations in Normal and Ataxia Telangiectasia Fibroblast Cells

NASA Astrophysics Data System (ADS)

Kawata, Tetsuya; George, Ms Kerry; Cucinotta, Francis A.; Shigematsu, Naoyuki; Ito, Hisao; Furusawa, Yoshiya; Uno, Takashi

We investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/micron), 500 MeV/u Iron (LET 185 keV/micron) and 200 MeV/u Iron (LET 440 keV/micron) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exchanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/micron and then decreased at 440 keV/micron. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/micron there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for normal fibroblast cells when it was compared at 185 keV/micron, but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types between normal and AT fibroblast appeared different probably due to difference in the ATM gene function.

Effects of ozone exposure on human epithelial adenocarcinoma and normal fibroblasts cells.

PubMed

Poma, Anna; Colafarina, Sabrina; Aruffo, Eleonora; Zarivi, Osvaldo; Bonfigli, Antonella; Di Bucchianico, Sebastiano; Di Carlo, Piero

2017-01-01

Previous studies show variable ozone cytotoxicity and genotoxicity in cell cultures, laboratory animals and humans directly exposed to tropospheric ozone. The aim of this study was therefore to investigate and compare the cyto and genotoxic effects of ozone using adenocarcinoma human alveolar basal epithelial cells A549 and normal human fibroblasts Hs27. A cell culture chamber with controlled atmosphere (a simulation reactor) was built to inject a flow of 120 ppb of ozone, which is two times the threshold value for the protection of human health, fixed by the EU legislation. Cell proliferation was evaluated by a luminescent cell viability assay while we assessed the genotoxic potential of ozone by the induction of micronuclei as well as evaluating DNA strand breaks by the induction of micronuclei evaluated by means of the cytokinesis-block micronucleus (CBMN) assay as well as evaluating DNA strand breaks by Alkaline Comet Assay (CA) or Comet Assay. A549 cells viability decreases significantly at 24 hours treatment with 120 ppb of O3 while at 48 hours and 72 hours O3 treated cells viability doesn't differ in respect to the control. However a significative decrease of A549 viability is shown at 72 hours vs. 48 hours in both treated and not-treated cells. The viability trend in the Hs27 cells did not show any significant changes in treated samples compared to the control in all conditions. The two genotoxicity biomarkers, the micronucleus and the comet tests, showed in both the cell types exposed to ozone, a significant increase in the number of micronuclei and in the tail DNA % in respect to the control even if at different times/cell type. Moreover, we found that O3 provokes genotoxic effects more evident in A549 cancer cells than in normal fibroblasts Hs27 ones. We applied a cell growth simulation model referred to ozone treated or not cell lines to confirm that the ozone exposure causes a slackening in the cells replication.

Reduced chromosome aberration complexity in normal human bronchial epithelial cells exposed to low-LET γ-rays and high-LET α-particles

PubMed Central

2013-01-01

Purpose: Cells of the lung are at risk from exposure to low and moderate doses of ionizing radiation from a range of environmental and medical sources. To help assess human health risks from such exposures, a better understanding of the frequency and types of chromosome aberration initially-induced in human lung cell types is required to link initial DNA damage and rearrangements with transmission potential and, to assess how this varies with radiation quality. Materials and methods: We exposed normal human bronchial lung epithelial (NHBE) cells in vitro to 0.5 and 1 Gy low-linear energy transfer (LET) γ-rays and a low fluence of high-LET α-particles and assayed for chromosome aberrations in premature chromosome condensation (PCC) spreads by 24-color multiplex-fluorescence in situ hybridization (M-FISH). Results: Both simple and complex aberrations were induced in a LET and dose-dependent manner; however, the frequency and complexity observed were reduced in comparison to that previously reported in spherical cell types after exposure to comparable doses or fluence of radiation. Approximately 1–2% of all exposed cells were categorized as being capable of transmitting radiation-induced chromosomal damage to future NHBE cell generations, irrespective of dose. Conclusion: One possible mechanistic explanation for this reduced complexity is the differing geometric organization of chromosome territories within ellipsoid nuclei compared to spherical nuclei. This study highlights the need to better understand the role of nuclear organization in the formation of exchange aberrations and, the influence three-dimensional (3D) tissue architecture may have on this in vivo. PMID:23679558

Deletion of Rab GAP AS160 modifies glucose uptake and GLUT4 translocation in primary skeletal muscles and adipocytes and impairs glucose homeostasis.

PubMed

Lansey, Melissa N; Walker, Natalie N; Hargett, Stefan R; Stevens, Joseph R; Keller, Susanna R

2012-11-15

Tight control of glucose uptake in skeletal muscles and adipocytes is crucial to glucose homeostasis and is mediated by regulating glucose transporter GLUT4 subcellular distribution. In cultured cells, Rab GAP AS160 controls GLUT4 intracellular retention and release to the cell surface and consequently regulates glucose uptake into cells. To determine AS160 function in GLUT4 trafficking in primary skeletal muscles and adipocytes and investigate its role in glucose homeostasis, we characterized AS160 knockout (AS160(-/-)) mice. We observed increased and normal basal glucose uptake in isolated AS160(-/-) adipocytes and soleus, respectively, while insulin-stimulated glucose uptake was impaired and GLUT4 expression decreased in both. No such abnormalities were found in isolated AS160(-/-) extensor digitorum longus muscles. In plasma membranes isolated from AS160(-/-) adipose tissue and gastrocnemius/quadriceps, relative GLUT4 levels were increased under basal conditions and remained the same after insulin treatment. Concomitantly, relative levels of cell surface-exposed GLUT4, determined with a glucose transporter photoaffinity label, were increased in AS160(-/-) adipocytes and normal in AS160(-/-) soleus under basal conditions. Insulin augmented cell surface-exposed GLUT4 in both. These observations suggest that AS160 is essential for GLUT4 intracellular retention and regulation of glucose uptake in adipocytes and skeletal muscles in which it is normally expressed. In vivo studies revealed impaired insulin tolerance in the presence of normal (male) and impaired (female) glucose tolerance. Concurrently, insulin-elicited increases in glucose disposal were abolished in all AS160(-/-) skeletal muscles and liver but not in AS160(-/-) adipose tissues. This suggests AS160 as a target for differential manipulation of glucose homeostasis.

The potential for chemical mixtures from the environment to enable the cancer hallmark of sustained proliferative signalling

PubMed Central

Engström, Wilhelm; Darbre, Philippa; Eriksson, Staffan; Gulliver, Linda; Hultman, Tove; Karamouzis, Michalis V.; Klaunig, James E.; Mehta, Rekha; Moorwood, Kim; Sanderson, Thomas; Sone, Hideko; Vadgama, Pankaj; Wagemaker, Gerard; Ward, Andrew; Singh, Neetu; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Colacci, Anna Maria; Vaccari, Monica; Mondello, Chiara; Scovassi, A. Ivana; Raju, Jayadev; Hamid, Roslida A.; Memeo, Lorenzo; Forte, Stefano; Roy, Rabindra; Woodrick, Jordan; Salem, Hosni K.; Ryan, Elizabeth; Brown, Dustin G.; Bisson, William H.

2015-01-01

The aim of this work is to review current knowledge relating the established cancer hallmark, sustained cell proliferation to the existence of chemicals present as low dose mixtures in the environment. Normal cell proliferation is under tight control, i.e. cells respond to a signal to proliferate, and although most cells continue to proliferate into adult life, the multiplication ceases once the stimulatory signal disappears or if the cells are exposed to growth inhibitory signals. Under such circumstances, normal cells remain quiescent until they are stimulated to resume further proliferation. In contrast, tumour cells are unable to halt proliferation, either when subjected to growth inhibitory signals or in the absence of growth stimulatory signals. Environmental chemicals with carcinogenic potential may cause sustained cell proliferation by interfering with some cell proliferation control mechanisms committing cells to an indefinite proliferative span. PMID:26106143

Chronic electronic cigarette exposure in mice induces features of COPD in a nicotine-dependent manner.

PubMed

Garcia-Arcos, Itsaso; Geraghty, Patrick; Baumlin, Nathalie; Campos, Michael; Dabo, Abdoulaye Jules; Jundi, Bakr; Cummins, Neville; Eden, Edward; Grosche, Astrid; Salathe, Matthias; Foronjy, Robert

2016-12-01

The use of electronic (e)-cigarettes is increasing rapidly, but their lung health effects are not established. Clinical studies examining the potential long-term impact of e-cigarette use on lung health will take decades. To address this gap in knowledge, this study investigated the effects of exposure to aerosolised nicotine-free and nicotine-containing e-cigarette fluid on mouse lungs and normal human airway epithelial cells. Mice were exposed to aerosolised phosphate-buffered saline, nicotine-free or nicotine-containing e-cigarette solution, 1-hour daily for 4 months. Normal human bronchial epithelial (NHBE) cells cultured at an air-liquid interface were exposed to e-cigarette vapours or nicotine solutions using a Vitrocell smoke exposure robot. Inhalation of nicotine-containing e-cigarettes increased airway hyper-reactivity, distal airspace enlargement, mucin production, cytokine and protease expression. Exposure to nicotine-free e-cigarettes did not affect these lung parameters. NHBE cells exposed to nicotine-containing e-cigarette vapour showed impaired ciliary beat frequency, airway surface liquid volume, cystic fibrosis transmembrane regulator and ATP-stimulated K+ ion conductance and decreased expression of FOXJ1 and KCNMA1. Exposure of NHBE cells to nicotine for 5 days increased interleukin (IL)-6 and IL-8 secretion. Exposure to inhaled nicotine-containing e-cigarette fluids triggered effects normally associated with the development of COPD including cytokine expression, airway hyper-reactivity and lung tissue destruction. These effects were nicotine-dependent both in the mouse lung and in human airway cells, suggesting that inhaled nicotine contributes to airway and lung disease in addition to its addictive properties. Thus, these findings highlight the potential dangers of nicotine inhalation during e-cigarette use. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Hyperplasia of type 2 pneumocytes following 0. 34 ppm nitrogen dioxide exposure: quantitation by image analysis. [Mice

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

Sherwin, R.P.; Richters, V.

1982-09-01

Swiss Webster male mice were exposed to intermittent 0.34 ppm nitrogen dioxide for 6 wk. Quantitative image analysis showed increased Type 2 cell numbers in each of the three lobes measured, with and without adjustment to alveolar wall measurements for lung volume normalization (e.g., P < .037 for Type 2 cell number adjusted to alveolar wall perimeters, combined lobe analysis of variance). The exposed animals dominated the upper quartile ranking of the cell number/alveolar area ratio computations (P < .025), which implied the presence of an especially susceptible subpopulation of animals. The Type 2 cell increase is believed to resultmore » from damage and loss of Type 1 cells, the reversibility and progression of which are presently unknown. The data also suggest an increased size of the Type 2 cell, and possibly slight atelectasis and/or edema of the alveolar walls.« less

AN INDIRECT METHOD TO ASSAY FOR MITOTIC CENTERS IN SAND DOLLAR (DENDRASTER EXCENTRICUS) EGGS

PubMed Central

Went, Hans A.

1966-01-01

It is possible consistently to induce sea urchin and sand dollar eggs to cleave directly from one cell into four cells. This is done by exposing the fertilized eggs to benzimidazole for 20 to 30 min beginning about early metaphase. The mitotic apparatus regresses, the cells do not cleave, and shortly after they are returned to normal sea water an early-prophase-appearing nucleus is present in each cell. Each cell then organizes a tetrapolar tetrahedral mitotic apparatus de novo, instead of transforming a bipolar mitotic apparatus into a tetrapolar figure, and cleaves one-to-four. In another type of experiment, it appears that sand dollar eggs exposed to mercaptoethanol during the first period of mitotic center duplication have only half as many centers by first cleavage metaphase as the normal controls. This is consistent with an earlier report by Mazia et al (1960). Using this same experimental technique, it was demonstrated that benzimidazole, on the contrary, does not interfere with mitotic center duplication in sand dollar eggs. A labeling experiment demonstrated that benzimidazole does not interfere markedly with the normal pattern of incorporation of C14-thymidine into the DNA of sea urchin eggs. The data reported here suggest that judicious treatment of sand dollar eggs (and probably sea urchin eggs, too) with benzimidazole can induce the eggs to cleave into as many cells as there were mitotic centers sometime earlier, for example at early metaphase of the first cleavage division. This provides a very useful tool for studies on the process of mitotic center duplication. PMID:6008198

An indirect method to assay for mitotic centers in sand dollar (Dendraster excentricus) eggs.

PubMed

Went, H A

1966-09-01

It is possible consistently to induce sea urchin and sand dollar eggs to cleave directly from one cell into four cells. This is done by exposing the fertilized eggs to benzimidazole for 20 to 30 min beginning about early metaphase. The mitotic apparatus regresses, the cells do not cleave, and shortly after they are returned to normal sea water an early-prophase-appearing nucleus is present in each cell. Each cell then organizes a tetrapolar tetrahedral mitotic apparatus de novo, instead of transforming a bipolar mitotic apparatus into a tetrapolar figure, and cleaves one-to-four. In another type of experiment, it appears that sand dollar eggs exposed to mercaptoethanol during the first period of mitotic center duplication have only half as many centers by first cleavage metaphase as the normal controls. This is consistent with an earlier report by Mazia et al (1960). Using this same experimental technique, it was demonstrated that benzimidazole, on the contrary, does not interfere with mitotic center duplication in sand dollar eggs. A labeling experiment demonstrated that benzimidazole does not interfere markedly with the normal pattern of incorporation of C(14)-thymidine into the DNA of sea urchin eggs. The data reported here suggest that judicious treatment of sand dollar eggs (and probably sea urchin eggs, too) with benzimidazole can induce the eggs to cleave into as many cells as there were mitotic centers sometime earlier, for example at early metaphase of the first cleavage division. This provides a very useful tool for studies on the process of mitotic center duplication.

Albumin-induced apoptosis of glomerular parietal epithelial cells is modulated by extracellular signal-regulated kinase 1/2

PubMed Central

Ohse, Takamoto; Krofft, Ron D.; Wu, Jimmy S.; Eddy, Allison A.; Pippin, Jeffrey W.; Shankland, Stuart J.

2012-01-01

Background. The biological role(s) of glomerular parietal epithelial cells (PECs) is not fully understood in health or disease. Given its location, PECs are constantly exposed to low levels of filtered albumin, which is increased in nephrotic states. We tested the hypothesis that PECs internalize albumin and increased uptake results in apoptosis. Methods. Confocal microscopy of immunofluorescent staining and immunohistochemistry were used to demonstrate albumin internalization in PECs and to quantitate albumin uptake in normal mice and rats as well as experimental models of membranous nephropathy, minimal change disease/focal segmental glomerulosclerosis and protein overload nephropathy. Fluorescence-activated cell sorting analysis was performed on immortalized cultured PECs exposed to fluorescein isothiocyanate (FITC)-labeled albumin in the presence of an endosomal inhibitor or vehicle. Apoptosis was measured by Hoechst staining in cultured PECs exposed to bovine serum albumin. Levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) were restored by retroviral infection of mitogen-activated protein kinase (MEK) 1/2 and reduced by U0126 in PECs exposed to high albumin levels in culture and apoptosis measured by Hoechst staining. Results. PECs internalized albumin normally, and this was markedly increased in all of the experimental disease models (P < 0.05 versus controls). Cultured immortalized PECs also internalize FITC-labeled albumin, which was reduced by endosomal inhibition. A consequence of increased albumin internalization was PEC apoptosis in vitro and in vivo. Candidate signaling pathways underlying these events were examined. Data showed markedly reduced levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (ERK1/2) in PECs exposed to high albumin levels in nephropathy and in culture. A role for ERK1/2 in limiting albumin-induced apoptosis was shown by restoring p-ERK1/2 by retroviral infection, which reduced apoptosis in cultured PECs, while a forced decrease of p-ERK1/2 through inhibition of MEK 1/2 significantly increased albumin-induced PEC apoptosis. Conclusions. A normal role of PECs is to take up filtered albumin. However, this is increased in proteinuric glomerular diseases, leading to apoptosis through changes in ERK1/2. PMID:21896500

DNA methylation in lung tissues of mouse offspring exposed in utero to polycyclic aromatic hydrocarbons.

PubMed

Fish, Trevor J; Benninghoff, Abby D

2017-11-01

Polycyclic aromatic hydrocarbons (PAHs) comprise an important class of environmental pollutants that are known to cause lung cancer in animals and are suspected lung carcinogens in humans. Moreover, evidence from cell-based studies points to PAHs as modulators of the epigenome. The objective of this work was to assess patterns of genome-wide DNA methylation in lung tissues of adult offspring initiated in utero with the transplacental PAH carcinogens dibenzo [def,p]chrysene (DBC) or benzo [a]pyrene (BaP). Genome-wide methylation patterns for normal (not exposed), normal adjacent and lung tumor tissues obtained from adult offspring were determined using methylated DNA immunoprecipitation (MeDIP) with the NimbleGen mouse DNA methylation CpG island array. Lung tumor incidence in 45-week old mice initiated with BaP was 32%, much lower than that of the DBC-exposed offspring at 96%. Also, male offspring appeared more susceptible to BaP as compared to females. Distinct patterns of DNA methylation were associated with non-exposed, normal adjacent and adenocarcinoma lung tissues, as determined by principal components, hierarchical clustering and gene ontology analyses. From these methylation profiles, a set of genes of interest was identified that includes potential important targets for epigenetic modification during the process of lung tumorigenesis in animals exposed to environmental PAHs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lognormal Distribution of Cellular Uptake of Radioactivity: Statistical Analysis of α-Particle Track Autoradiography

PubMed Central

Neti, Prasad V.S.V.; Howell, Roger W.

2010-01-01

Recently, the distribution of radioactivity among a population of cells labeled with 210Po was shown to be well described by a log-normal (LN) distribution function (J Nucl Med. 2006;47:1049–1058) with the aid of autoradiography. To ascertain the influence of Poisson statistics on the interpretation of the autoradiographic data, the present work reports on a detailed statistical analysis of these earlier data. Methods The measured distributions of α-particle tracks per cell were subjected to statistical tests with Poisson, LN, and Poisson-lognormal (P-LN) models. Results The LN distribution function best describes the distribution of radioactivity among cell populations exposed to 0.52 and 3.8 kBq/mL of 210Po-citrate. When cells were exposed to 67 kBq/mL, the P-LN distribution function gave a better fit; however, the underlying activity distribution remained log-normal. Conclusion The present analysis generally provides further support for the use of LN distributions to describe the cellular uptake of radioactivity. Care should be exercised when analyzing autoradiographic data on activity distributions to ensure that Poisson processes do not distort the underlying LN distribution. PMID:18483086

Microtubule Abnormalities Underlying Gulf War Illness in Neurons from Human-Induced Pluripotent Cells

DTIC Science & Technology

2016-09-01

AWARD NUMBER: W81XWH-15-1-0433 TITLE: Microtubule Abnormalities Underlying Gulf War Illness in Neurons from Human -Induced Pluripotent Cells...2015 - 31 Aug 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Microtubule Abnormalities Underlying Gulf War Illness in Neurons from Human -Induced...functions to normal in neurons derived from human pluripotent cells exposed to Gulf War toxins. 15. SUBJECT TERMS microtubule, neuron, Gulf War Illness

Tea extracts protect normal lymphocytes but not leukemia cells from UV radiation-induced ROS production: An EPR spin trap study.

PubMed

Tepe Çam, Semra; Polat, Mustafa; Esmekaya, Meriç Arda; Canseven, Ayşe G; Seyhan, Nesrin

2015-08-01

An ex vivo method for detection of free radicals and their neutralization by aqueous tea in human normal lymphocytes and MEC-1 leukemia cells under ultraviolet (UV) irradiation was investigated. This method is based on the electron paramagnetic resonance (EPR) spectroscopy spin-trapping technique. 5-tert-butoxycarbonyl 5-methyl-1-pyrroline N-oxide (BMPO) was used as the spin trap. Normal human lymphocytes and leukemia cells were exposed to UVB radiation (290-315 nm) at 47.7 and 159 mJ/cm(2) and to UVA radiation (315-400 nm) at 53.7 J/cm(2). No significant radical production at 47.7 mJ/cm(2) UVB dose in both cell lines was observed. In normal cells, free radical production was observed at 159 mJ/cm(2) UVB and 53.7 J/cm(2) UVA doses. However, both UV sources did not significantly produce free radicals in leukemia cells. A radical scavenging property of tea extracts (black, green, sage, rosehip) was observed in normal lymphocytes after both UVB and UVA exposure. In leukemia cells, the intensities of EPR signals produced in BMPO with tea extracts were found to be increased substantially after UVA exposure. These results showed that UV radiation induced free radical formation in normal human lymphocytes and indicated that tea extracts may be useful as photoprotective agents for them. On the other hand, tea extracts facilitated free radical production in leukemia cells.

Acute toxic effects of nerve agent VX on respiratory dynamics and functions following microinsillation inhalation exposure in guinea pigs.

PubMed

Rezk, Peter E; Graham, Jacob R; Moran, Theodore S; Gordon, Richard K; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2007-03-01

Exposure to a chemical warfare nerve agent (CWNA) leads to severe respiratory distress, respiratory failure, or death if not treated. We investigated the toxic effects of nerve agent VX on the respiratory dynamics of guinea pigs following exposure to 90.4 mug/m3 of VX or saline by microinstillation inhalation technology for 10 min. Respiratory parameters were monitored by whole-body barometric plethysmography at 4, 24, and 48 h, 7 d, 18 d, and 4 wk after VX exposure. VX-exposed animals showed a significant decrease in the respiratory frequency (RF) at 24 and 48 h of recovery (p value .0329 and .0142, respectively) compared to the saline control. The tidal volume (TV) slightly increased in VX exposed animals at 24 and significantly at 48 h (p = .02) postexposure. Minute ventilation (MV) increased slightly at 4 h but was reduced at 24 h and remained unchanged at 48 h. Animals exposed to VX also showed an increase in expiratory (Te) and relaxation time (RT) at 24 and 48 h and a small reduction in inspiratory time (Ti) at 24 h. A significant increase in end expiratory pause (EEP) was observed at 48 h after VX exposure (p = .049). The pseudo lung resistance (Penh) was significantly increased at 4 h after VX exposure and remained slightly high even at 48 h. Time-course studies reveal that most of the altered respiratory dynamics returned to normal at 7 d after VX exposure except for EEP, which was high at 7 d and returned to normal at 18 d postexposure. After 1 mo, all the monitored respiratory parameters were within normal ranges. Bronchoalveolar lavage (BAL) 1 mo after exposure showed virtually no difference in protein levels, cholinesterase levels, cell number, and cell death in the exposed and control animals. These results indicate that sublethal concentrations of VX induce changes in respiratory dynamics and functions that over time return to normal levels.

Long-Term, Low-Dose Exposure to Microcystin-LR Does not Cause or Increase the Severity of Liver Disease in Rodents.

PubMed

Labine, Meaghan; Gong, Yuewen; Minuk, Gerald Y

Acute exposure to high concentrations of microcystin-LR (MC-LR) can cause significant hepatocyte injury. To document the effects of long-term, low-dose MC-LR exposure on hepatic inflammation and fibrosis in mice with healthy and diseased livers. Male CD1 mice (N = 20/group) were exposed to 1.0 μg/L of MC-LR in drinking water; 1.0 μg/L MC-LR plus 300 mg/L of the hepatotoxin thioacetamide (MC-LR/TAA); or 300 mg/L TAA alone for 28 weeks. Liver biochemistry and histology were documented at the end of the study period. In addition, hepatic stellate cells (HSCs), were exposed in vitro to MC-LR (0.1-10,000 μg/L) and monitored for changes in cell metabolism, proliferation and activation. Liver biochemistry and histology were essentially normal in MC-LR alone exposed mice. MC-LR/TAA and TAA alone exposed mice had significant hepatic inflammation and fibrosis but the extent of the changes were similar in the two groups. In vitro, MC-LR had no effect on HSC metabolism, proliferation or activation. Long-term, low-dose exposure to MC-LR is unlikely to lead to chronic liver disease in the setting of a normal liver or exacerbate existing liver disease in the setting of ongoing hepatitis.

Phosphatidylserine on blood cells and endothelial cells contributes to the hypercoagulable state in cirrhosis.

PubMed

Wu, Xiaoming; Yao, Zhipeng; Zhao, Lu; Zhang, Yan; Cao, Muhua; Li, Tao; Ding, Wenbo; Liu, Yan; Deng, Ruijuan; Dong, Zengxiang; Chen, He; Novakovic, Valerie A; Bi, Yayan; Kou, Junjie; Tian, Ye; Zhou, Jin; Shi, Jialan

2016-12-01

The mechanism of thrombogenicity in cirrhosis is largely unknown. Our objective was to study the relationship between phosphatidylserine on blood cells and endothelial cells and the hypercoagulable state in cirrhotic patients. Patients with cirrhosis and healthy controls were studied. Lactadherin was used to quantify phosphatidylserine exposure on blood cells and endothelial cells. Procoagulant activity of cells was evaluated using clotting time and purified coagulation complex assays. Fibrin production was determined by turbidity. Phosphatidylserine exposure, fibrin strands and FVa/Xa binding on cells were observed using confocal microscopy. Our study showed that phosphatidylserine exposure on erythrocytes, platelets and leucocytes in cirrhotic patients increased progressively with Child-Pugh categories. In addition, we found that endothelial cells treated with cirrhotic serum in vitro exposed more phosphatidylserine than those exposed to healthy serum. The exposed phosphatidylserine supported a shorter coagulation time and increased FXa, thrombin and fibrin formation. Notably, phosphatidylserine + erythrocytes also promoted shorter coagulation times and more fibrin generation in cirrhotic microparticle-depleted plasma, regardless of Child-Pugh categories. Confocal microscopy data showed that the FVa/FXa complex and fibrin fibrils colocalized with phosphatidylserine on endothelial cells. Lactadherin significantly inhibited FXa and thrombin generation and consequently decreased fibrin production in normal or cirrhotic plasma. These results lead us to believe that exposed phosphatidylserine on activated or injured erythrocytes, platelets, leucocytes and endothelial cells plays an important role in the hypercoagulable state in cirrhotic patients. Thus, blocking phosphatidylserine binding sites might be a new therapeutic target for preventing thrombosis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measurement of DNA repair deficiency in workers exposed to benzene

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

Hallberg, L.M.; Au, W.W.; El Zein, R.

1996-05-01

We hypothesize that chronic exposure to environmental toxicants can induce genetic damage causing DNA repair deficiencies and leading to the postulated mutator phenotype of carcinogenesis. To test our hypothesis, a host cell reactivation (HCR) assay was used in which pCMVcat plasmids were damaged with UV light (175, 350 J/m{sup 2} UV light), inactivating the chloramphenicol acetyltransferase reporter gene, and then transfected into lymphocytes. Transfected lymphocytes were therefore challenged to repair the damaged plasmids, reactivating the reporter gene. Xeroderma pigmentosum (XP) and Gaucher cell lines were used as positive and negative controls for the HCR assay. The Gaucher cell line repairedmore » normally but XP cell lines demonstrated lower repair activity. Additionally, the repair activity of the XP heterozygous cell line showed intermediate repair compared to the homozygous XP and Gaucher cells. We used HCR to measure the effects of benzene exposure on 12 exposed and 8 nonexposed workers from a local benzene plant. Plasmids 175 J/m{sup 2} and 350 J/m{sup 2} were repaired with a mean frequency of 66% and 58%, respectively, in control workers compared to 71% and 62% in exposed workers. Conversely, more of the exposed workers were grouped into the reduced repair category than controls. These differences in repair capacity between exposed and control workers were, however, not statistically significant. The lack of significant differences between the exposed and control groups may be due to extremely low exposure to benzene (<0.3 ppm), small population size, or a lack of benzene genotoxicity at these concentrations. These results are consistent with a parallel hprt gene mutation assay. 26 refs., 4 figs., 2 tabs.« less

Selective effect of irradiation on responses to thymus-independent antigen.

PubMed

Lee, S K; Woodland, R T

1985-02-01

Low doses of ionizing radiation have a selective immunosuppressive effect on in vivo B cell responses to thymus-independent (TI) antigens. The B cell response, assayed as direct anti-trinitrophenyl (TNP)-specific plaque-forming cells (PFC), induced by type 2, TI antigens (TNP-Ficoll or TNP-Dextran), was reduced, on the average, by 10-fold in animals exposed to 200 rad of ionizing radiation 24 hr before antigen challenge. In contrast, PFC responses to type 1, TI antigens (TNP-lipopolysaccharide or TNP-Brucella abortus) are unaffected in mice exposed to the same dose of radiation. Adoptive transfers showed that this selective immunosuppression is a result of the specific inactivation of the B cell subpopulation responding to type 2, TI antigens. These experiments suggest that physiologic differences exist in the B cell subpopulations of normal mice which respond to type 1, or type 2, TI antigens.

Dependence of Early and Late Chromosomal Aberrations on Radiation Quality and Cell Types

NASA Technical Reports Server (NTRS)

Lu, Tao; Zhang, Ye; Krieger, Stephanie; Yeshitla, Samrawit; Goss, Rosalin; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Rohde, Larry; Wu, Honglu

2017-01-01

Exposure to radiation induces different types of DNA damage, increases mutation and chromosome aberration rates, and increases cellular transformation in vitro and in vivo. The susceptibility of cells to radiation depends on genetic background and growth condition of cells, as well as types of radiation. Mammalian cells of different tissue types and with different genetic background are known to have different survival rate and different mutation rate after cytogenetic insults. Genomic instability, induced by various genetic, metabolic, and environmental factors including radiation, is the driving force of tumorigenesis. Accurate measurements of the relative biological effectiveness (RBE) is important for estimating radiation-related risks. To further understand genomic instability induced by charged particles and their RBE, we exposed human lymphocytes ex vivo, human fibroblast AG1522, human mammary epithelial cells (CH184B5F5/M10), and bone marrow cells isolated from CBA/CaH(CBA) and C57BL/6 (C57) mice to high energy protons and Fe ions. Normal human fibroblasts AG1522 have apparently normal DNA damage response and repair mechanisms, while mammary epithelial cells (M10) are deficient in the repair of DNA DSBs. Mouse strain CBA is radio-sensitive while C57 is radio-resistant. Metaphase chromosomes at different cell divisions after radiation exposure were collected and chromosome aberrations were analyzed as RBE for different cell lines exposed to different radiations at various time points up to one month post irradiation.

Cancer Secretome May Influence BSP and DSP Expression in Human Salivary Gland Cells

PubMed Central

Hamilton, Samantha Lynn; Ferando, Blake; Eapen, Asha Sarah; Yu, Jennifer Chian; Joy, Anita Rose

2016-01-01

One of the biggest challenges in managing head and neck cancers, especially salivary gland cancers, is the identification of secreted biomarkers of the disease that can be evaluated noninvasively. A relevant source of enriched tumor markers could potentially be found in the tumor secretome. Although numerous studies have evaluated secretomes from various cancers, the influence of the cancer secretome derived from salivary gland cancers on the behavior of normal cells has not yet been elucidated. Our data indicate that secretome derived from salivary gland cancer cells can influence the expression of two potential biomarkers of oral cancer—namely, bone sialoprotein (BSP) and dentin sialoprotein (DSP)—in normal salivary gland cells. Using routine immunohistochemistry, immunofluorescence, and immunoblotting techniques, we demonstrate an enrichment of BSP and DSP in human salivary gland (HSG) cancer tissue, unique localizations of BSP and DSP in HSG cancer cells, and enriched expression of BSP and DSP in normal salivary gland cells exposed to a cancer secretome. The secretome domain of the cancer microenvironment could alter signaling cascades responsible for normal cell proliferation, migration, and invasion, thus enhancing cancer cell survival and the potential for cancer progression. The cancer secretome may be critical in maintaining and stimulating “cancer-ness,” thus potentially promoting specific hallmarks of metastasis. PMID:27881474

Cancer Secretome May Influence BSP and DSP Expression in Human Salivary Gland Cells.

PubMed

Hamilton, Samantha Lynn; Ferando, Blake; Eapen, Asha Sarah; Yu, Jennifer Chian; Joy, Anita Rose

2017-03-01

One of the biggest challenges in managing head and neck cancers, especially salivary gland cancers, is the identification of secreted biomarkers of the disease that can be evaluated noninvasively. A relevant source of enriched tumor markers could potentially be found in the tumor secretome. Although numerous studies have evaluated secretomes from various cancers, the influence of the cancer secretome derived from salivary gland cancers on the behavior of normal cells has not yet been elucidated. Our data indicate that secretome derived from salivary gland cancer cells can influence the expression of two potential biomarkers of oral cancer-namely, bone sialoprotein (BSP) and dentin sialoprotein (DSP)-in normal salivary gland cells. Using routine immunohistochemistry, immunofluorescence, and immunoblotting techniques, we demonstrate an enrichment of BSP and DSP in human salivary gland (HSG) cancer tissue, unique localizations of BSP and DSP in HSG cancer cells, and enriched expression of BSP and DSP in normal salivary gland cells exposed to a cancer secretome. The secretome domain of the cancer microenvironment could alter signaling cascades responsible for normal cell proliferation, migration, and invasion, thus enhancing cancer cell survival and the potential for cancer progression. The cancer secretome may be critical in maintaining and stimulating "cancer-ness," thus potentially promoting specific hallmarks of metastasis.

Thyroid Cells Exposed to Simulated Microgravity Conditions - Comparison of the Fast Rotating Clinostat and the Random Positioning Machine

NASA Astrophysics Data System (ADS)

Warnke, Elisabeth; Kopp, Sascha; Wehland, Markus; Hemmersbach, Ruth; Bauer, Johann; Pietsch, Jessica; Infanger, Manfred; Grimm, Daniela

2016-06-01

The ground-based facilities 2D clinostat (CN) and Random Positioning Machine (RPM) were designed to simulate microgravity conditions on Earth. With support of the CORA-ESA-GBF program we could use both facilities to investigate the impact of simulated microgravity on normal and malignant thyroid cells. In this review we report about the current knowledge of thyroid cancer cells and normal thyrocytes grown under altered gravity conditions with a special focus on growth behaviour, changes in the gene expression pattern and protein content, as well as on altered secretion behaviour of the cells. We reviewed data obtained from normal thyrocytes and cell lines (two poorly differentiated follicular thyroid cancer cell lines FTC-133 and ML-1, as well as the normal thyroid cell lines Nthy-ori 3-1 and HTU-5). Thyroid cells cultured under conditions of simulated microgravity (RPM and CN) and in Space showed similar changes with respect to spheroid formation. In static 1 g control cultures no spheroids were detectable. Changes in the regulation of cytokines are discussed to be involved in MCS (multicellular spheroids) formation. The ESA-GBF program helps the scientists to prepare future spaceflight experiments and furthermore, it might help to identify targets for drug therapy against thyroid cancer.

Mechanisms of Radiation Toxicity in Transformed and Non-Transformed Cells

PubMed Central

Panganiban, Ronald-Allan M.; Snow, Andrew L.; Day, Regina M.

2013-01-01

Radiation damage to biological systems is determined by the type of radiation, the total dosage of exposure, the dose rate, and the region of the body exposed. Three modes of cell death—necrosis, apoptosis, and autophagy—as well as accelerated senescence have been demonstrated to occur in vitro and in vivo in response to radiation in cancer cells as well as in normal cells. The basis for cellular selection for each mode depends on various factors including the specific cell type involved, the dose of radiation absorbed by the cell, and whether it is proliferating and/or transformed. Here we review the signaling mechanisms activated by radiation for the induction of toxicity in transformed and normal cells. Understanding the molecular mechanisms of radiation toxicity is critical for the development of radiation countermeasures as well as for the improvement of clinical radiation in cancer treatment. PMID:23912235

The effect of fibrin on cultured vascular endothelial cells.

PubMed

Kadish, J L; Butterfield, C E; Folkman, J

1979-01-01

The normal cobblestone monolayer architecture of cultured vascular endothelium becomes rapidly disorganized after contact of the cell layer with a fibrin clot. The cells of a confluent endothelial monolayer separate into individual migratory cells in 4--6 hr after contact with fibrin. The effect is reversible in that removal of the fibrin clot results in resumption of the normal morphology within about 2 hr. No other cell type tested exhibits the same change in organization when exposed to fibrin. A similar morphological change in endothelium does occur after the cell layer is overlaid with a collagen fibril gel but a gel of methylcellulose has no effect. It is proposed that the change in behavior of endothelial cells in response to contact with fibrin may represent a cellular component of fibrinolysis. The implications of this finding for the pathophysiology of disease states involving intravascular fibrin deposition are discussed.

CELLS INVOLVED IN THE IMMUNE RESPONSE

PubMed Central

Singhal, Sharwan K.; Richter, Maxwell

1968-01-01

Cell suspensions of immune rabbit lymph nodes and spleen were capable of undergoing blastogenesis and mitosis and of incorporating tritiated thymidine when maintained in culture with the specific antigen in vitro. They did not respond to other, non-cross-reacting antigens. The blastogenic response obtained with immune lymph node cells could be correlated with the antibody synthesizing capacity of fragment cultures prepared from the same lymph nodes. Cell suspensions of immune bone marrow responded to non-cross-reacting antigens only whereas cell suspensions of immune thymus, sacculus rotundus, and appendix did not respond when exposed to any of the antigens tested. On the other hand, neither fragments nor cell suspensions prepared from lymph nodes, spleen, and thymus of normal, unimmunized rabbits responded with antibody formation and blastogenesis when exposed to any of the antigens. However, normal bone marrow cells responded with marked blastogenesis and tritiated thymidine uptake. The specificity of this in vitro bone marrow response was demonstrated by the fact that the injection of a protein antigen in vivo resulted in the loss of reactivity by the marrow cell to that particular antigen but not to the other, non-cross-reacting antigens. Furthermore, bone marrow cells of tolerant rabbits failed to respond to the specific antigen in vitro. It was also demonstrated that normal bone marrow cells incubated with antigen are capable of forming antibody which could be detected by the fluorescent antibody technique. This response of the bone marrow cells has been localized to the lymphocyte-rich fraction of the bone marrow. It is concluded that the bone marrow lymphocyte, by virtue of its capacity to react with blastogenesis and mitosis and with antibody formation upon initial exposure to the antigen, a capacity not possessed by lymphocytes of the other lymphoid organs, has a preeminent role in the sequence of cellular events culminating in antibody formation. PMID:4176224

Adrenergic factors regulating cell division in the colonic crypt epithelium during carcinogenesis and in colonic adenoma and adenocarcinoma.

PubMed Central

Kennedy, M. F.; Tutton, P. J.; Barkla, D. H.

1985-01-01

Evidence exists implicating adrenergic factors in the control of intestinal epithelial cell proliferation in both normal and diseased states. In this report, attention is focussed on changes in the amine requirements of proliferating cells during the chemical induction of tumours in the colon of mouse. Cell proliferation rates were measured stathmokinetically. Tumours were induced by s.c. injection of dimethylhydrazine (DMH). Results with a series of adrenoceptor agonists and antagonists suggest that there is an alpha 2-adrenoceptor mediated excitatory effect in normal colon but an alpha 2 adrenoceptor mediated inhibitory effect in adenoma and carcinoma. Alpha 1 adrenoceptors, on the other hand, have an inhibitory effect in normal crypts and in adenomas, and an excitatory effect in carcinomas. Beta adrenoceptors have an inhibitory effect in the normal and DMH-treated crypt, and in adenomas, but not in carcinomas. In the crypt epithelium of DMH-treated mice, two regions on cell proliferation, with differing regulatory factors, could be identified. In the upper region of the carcinogen-exposed crypt is a zone where cell proliferation is stimulated by an alpha 2 adrenergic mechanism, thus resembling the basal region of the normal crypt. By contrast, in the basal region of these crypts, cell proliferation is stimulated by an alpha 1 mechanism, thus resembling a malignant tumour. PMID:4041364

Adrenergic factors regulating cell division in the colonic crypt epithelium during carcinogenesis and in colonic adenoma and adenocarcinoma.

PubMed

Kennedy, M F; Tutton, P J; Barkla, D H

1985-09-01

Evidence exists implicating adrenergic factors in the control of intestinal epithelial cell proliferation in both normal and diseased states. In this report, attention is focussed on changes in the amine requirements of proliferating cells during the chemical induction of tumours in the colon of mouse. Cell proliferation rates were measured stathmokinetically. Tumours were induced by s.c. injection of dimethylhydrazine (DMH). Results with a series of adrenoceptor agonists and antagonists suggest that there is an alpha 2-adrenoceptor mediated excitatory effect in normal colon but an alpha 2 adrenoceptor mediated inhibitory effect in adenoma and carcinoma. Alpha 1 adrenoceptors, on the other hand, have an inhibitory effect in normal crypts and in adenomas, and an excitatory effect in carcinomas. Beta adrenoceptors have an inhibitory effect in the normal and DMH-treated crypt, and in adenomas, but not in carcinomas. In the crypt epithelium of DMH-treated mice, two regions on cell proliferation, with differing regulatory factors, could be identified. In the upper region of the carcinogen-exposed crypt is a zone where cell proliferation is stimulated by an alpha 2 adrenergic mechanism, thus resembling the basal region of the normal crypt. By contrast, in the basal region of these crypts, cell proliferation is stimulated by an alpha 1 mechanism, thus resembling a malignant tumour.

On the Normal Force Mechanotransduction of Human Umbilical Vein Endothelial Cells

NASA Astrophysics Data System (ADS)

Vahabikashi, Amir; Wang, Qiuyun; Wilson, James; Wu, Qianhong; Vucbmss Team

2016-11-01

In this paper, we report a cellular biomechanics study to examine the normal force mechanotransduction of Human Umbilical Vein Endothelial Cells (HUVECs) with their implications on hypertension. Endothelial cells sense mechanical forces and adjust their structure and function accordingly. The mechanotransduction of normal forces plays a vital role in hypertension due to the higher pressure buildup inside blood vessels. Herein, HUVECs were cultured to full confluency and then exposed to different mechanical loadings using a novel microfluidic flow chamber. One various pressure levels while keeps the shear stress constant inside the flow chamber. Three groups of cells were examined, the control group (neither shear nor normal stresses), the normal pressure group (10 dyne/cm2 of shear stress and 95 mmHg of pressure), and the hypertensive group (10 dyne/cm2 of shear stress and 142 mmHg of pressure). Cellular response characterized by RT-PCR method indicates that, COX-2 expressed under normal pressure but not high pressure; Mn-SOD expressed under both normal and high pressure while this response was stronger for normal pressure; FOS and e-NOS did not respond under any condition. The differential behavior of COX-2 and Mn-SOD in response to changes in pressure, is instrumental for better understanding the pathogenesis of hypertensive cardiovascular diseases. This research was supported by the National Science Foundation under Award #1511096.

Protective effects of aerosolized scopolamine against soman-induced acute respiratory toxicity in guinea pigs.

PubMed

Perkins, Michael W; Pierre, Zdenka; Rezk, Peter; Song, Jian; Oguntayo, Samuel; Morthole, Venee; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2011-12-01

The protective efficacy of the antimuscarinic agent scopolamine was evaluated against soman (o-pinacolyl methylphosphonofluoridate [GD])-induced respiratory toxicity in guinea pigs. Anesthetized animals were exposed to GD (841 mg/m(3)) by microinstillation inhalation exposure and treated 30 seconds later with endotracheally aerosolized scopolamine (0.25 mg/kg) and allowed to recover for 24 hours. Treatment with scopolamine significantly increased survival and reduced clinical signs of toxicity and body weight loss in GD-exposed animals. Analysis of bronchoalveolar lavage (BAL) fluid showed normalization of GD-induced increased cell death, total cell count, and protein following scopolamine treatment. The BAL fluid acetylcholinesterase and butyrylcholinesterase levels were also increased by scopolamine treatment. Respiratory dynamics parameters were normalized at 4 and 24 hours post-GD exposure in scopolamine-treated animals. Lung histology showed that scopolamine treatment reduced bronchial epithelial and subepithelial inflammation and multifocal alveolar septal edema. These results suggest that aerosolized scopolamine considerably protects against GD-induced respiratory toxicity.

[ARTCEREB irrigation and perfusion solution for cerebrospinal surgery: pharmacological assessment using human astrocytes exposed to test solutions].

PubMed

Nishimura, Masuhiro; Doi, Kazuhisa; Enomoto, Riyo; Lee, Eibai; Naito, Shinsaku; Yamauchi, Aiko

2009-09-01

ARTCEREB irrigation and perfusion solution (Artcereb) is a preparation intended for the irrigation and perfusion of the cerebral ventricles, and it is therefore important to evaluate the effects of Artcereb on brain cells. In vitro assessment of the effects of Artcereb in cell cultures of human fetal astrocytes was conducted in comparison with normal saline and lactated Ringer's solution. The effects of exposure to Artcereb were evaluated based on microscopic images of the mitochondria stained with rhodamine 123. The effects of exposure to Artcereb on cell function were also evaluated by quantitative analysis of mitochondrial activity based on rhodamine 123 and (3)H-thymidine incorporation. Morphological changes in nuclear structure were also evaluated. The results of the present study showed that cell function in cell cultures of human astrocytes was relatively unaffected by exposure to Artcereb as compared with normal saline or lactated Ringer's solution, suggesting that Artcereb has less effect on brain cells than normal saline or lactated Ringer's solution when used for the irrigation or perfusion of the cerebral ventricles.

Nuclear accumulation of cyclin D1 following long-term fractionated exposures to low-dose ionizing radiation in normal human diploid cells.

PubMed

Shimura, Tsutomu; Hamada, Nobuyuki; Sasatani, Megumi; Kamiya, Kenji; Kunugita, Naoki

2014-01-01

Cyclin D1 is a mitogenic sensor that responds to growth signals from the extracellular environment and regulates the G 1-to-S cell cycle transition. When cells are acutely irradiated with a single dose of 10 Gy, cyclin D1 is degraded, causing cell cycle arrest at the G 1/S checkpoint. In contrast, cyclin D1 accumulates in human tumor cells that are exposed to long-term fractionated radiation (0.5 Gy/fraction of X-rays). In this study we investigated the effect of fractionated low-dose radiation exposure on cyclin D1 localization in 3 strains of normal human fibroblasts. To specifically examine the nuclear accumulation of cyclin D1, cells were treated with a hypotonic buffer containing detergent to remove cytoplasmic cyclin D1. Proliferating cell nuclear antigen (PCNA) immunofluorescence was used to identify cells in S phase. With this approach, we observed S-phase nuclear retention of cyclin D1 following low-dose fractionated exposures, and found that cyclin D1 nuclear retention increased with exposure time. Cells that retained nuclear cyclin D1 were more likely to have micronuclei than non-retaining cells, indicating that the accumulation of nuclear cyclin D1 was associated with genomic instability. Moreover, inhibition of the v-akt murine thymoma viral oncogene homolog (AKT) pathway facilitated cyclin D1 degradation and eliminated cyclin D1 nuclear retention in cells exposed to fractionated radiation. Thus, cyclin D1 may represent a useful marker for monitoring long-term effects associated with exposure to low levels of radiation.

Nuclear accumulation of cyclin D1 following long-term fractionated exposures to low-dose ionizing radiation in normal human diploid cells

PubMed Central

Shimura, Tsutomu; Hamada, Nobuyuki; Sasatani, Megumi; Kamiya, Kenji; Kunugita, Naoki

2014-01-01

Cyclin D1 is a mitogenic sensor that responds to growth signals from the extracellular environment and regulates the G1-to-S cell cycle transition. When cells are acutely irradiated with a single dose of 10 Gy, cyclin D1 is degraded, causing cell cycle arrest at the G1/S checkpoint. In contrast, cyclin D1 accumulates in human tumor cells that are exposed to long-term fractionated radiation (0.5 Gy/fraction of X-rays). In this study we investigated the effect of fractionated low-dose radiation exposure on cyclin D1 localization in 3 strains of normal human fibroblasts. To specifically examine the nuclear accumulation of cyclin D1, cells were treated with a hypotonic buffer containing detergent to remove cytoplasmic cyclin D1. Proliferating cell nuclear antigen (PCNA) immunofluorescence was used to identify cells in S phase. With this approach, we observed S-phase nuclear retention of cyclin D1 following low-dose fractionated exposures, and found that cyclin D1 nuclear retention increased with exposure time. Cells that retained nuclear cyclin D1 were more likely to have micronuclei than non-retaining cells, indicating that the accumulation of nuclear cyclin D1 was associated with genomic instability. Moreover, inhibition of the v-akt murine thymoma viral oncogene homolog (AKT) pathway facilitated cyclin D1 degradation and eliminated cyclin D1 nuclear retention in cells exposed to fractionated radiation. Thus, cyclin D1 may represent a useful marker for monitoring long-term effects associated with exposure to low levels of radiation. PMID:24583467

E-cigarette vapour is not inert and exposure can lead to cell damage.

PubMed

Holliday, Richard; Kist, Ralf; Bauld, Linda

2016-03-01

In vitro experiments were performed on normal epithelial cells as well as head and neck squamous cell carcinoma (HNSCC) cell lines. The widely available cell line HaCat, a spontaneously transformed immortal keratinocyte and the HNSCC cell lines HN30 and UMSCC10B were used. Cells were exposed to nicotine-containing and nicotine-free vapour extract from two popular e-cigarette brands for periods ranging from 48 hours to eight weeks. Cytotoxicity was assessed using Annexin V flow cytometric analysis, trypan blue exclusion and clonogenic assays. Genotoxicity in the form of DNA strand breaks was quantified using the neutral comet assay and γ-H2AX immunostaining. E-cigarette-exposed cells showed significantly reduced cell viability and clonogenic survival, along with increased rates of apoptosis and necrosis, regardless of e-cigarette vapour nicotine content. They also exhibited significantly increased comet tail length and accumulation of γ-H2AX foci, demonstrating increased DNA strand breaks. In conclusion, our study strongly suggests that electronic cigarettes are not as safe as their marketing makes them appear to the public. Our in vitro experiments employing two brands of e-cigs show that at biologically relevant doses, vapourised e-cig liquids induce increased DNA strand breaks and cell death, and decreased clono- genic survival in both normal epithelial and HNSCC cell lines independently of nicotine content. Further research is needed to definitively determine the long-term effects of e-cig usage, as well as whether the DNA damage shown in our study as a result of e-cig exposure will lead to mutations that ultimately result in cancer.

Dose responses for adaption to low doses of (60)Co gamma rays and (3)H beta particles in normal human fibroblasts.

PubMed

Broome, E J; Brown, D L; Mitchel, R E J

2002-08-01

The dose response for adaption to radiation at low doses was compared in normal human fibroblasts (AG1522) exposed to either (60)Co gamma rays or (3)H beta particles. Cells were grown in culture to confluence and exposed at either 37 degrees C or 0 degrees C to (3)H beta-particle or (60)Co gamma-ray adapting doses ranging from 0.1 mGy to 500 mGy. These cells, and unexposed control cells, were allowed to adapt during a fixed 3-h, 37 degrees C incubation prior to a 4-Gy challenge dose of (60)Co gamma rays. Adaption was assessed by measuring micronucleus frequency in cytokinesis-blocked, binucleate cells. No adaption was detected in cells exposed to (60)Co gamma radiation at 37 degrees C after a dose of 0.1 mGy given at a low dose rate or to 500 mGy given at a high dose rate. However, low-dose-rate exposure (1-3 mGy/min) to any dose between 1 and 500 mGy from either radiation, delivered at either temperature, caused cells to adapt and reduced the micronucleus frequency that resulted from the subsequent 4-Gy exposure. Within this dose range, the magnitude of the reduction was the same, regardless of the dose or radiation type. These results demonstrate that doses as low as (on average) about one track per cell (1 mGy) produce the same maximum adaptive response as do doses that deposit many tracks per cell, and that the two radiations were not different in this regard. Exposure at a temperature where metabolic processes, including DNA repair, were inactive (0 degrees C) did not alter the result, indicating that the adaptive response is not sensitive to changes in the accumulation of DNA damage within this range. The results also show that the RBE for low doses of tritium beta-particle radiation is 1, using adaption as the end point.

Resveratrol protects mouse embryonic stem cells from ionizing radiation by accelerating recovery from DNA strand breakage.

PubMed

Denissova, Natalia G; Nasello, Cara M; Yeung, Percy L; Tischfield, Jay A; Brenneman, Mark A

2012-01-01

Resveratrol has elicited many provocative anticancer effects in laboratory animals and cultured cells, including reduced levels of oxidative DNA damage, inhibition of tumor initiation and progression and induction of apoptosis in tumor cells. Use of resveratrol as a cancer-preventive agent in humans will require that its anticancer effects not be accompanied by damage to normal tissue stem or progenitor cells. In mouse embryonic stem cells (mESC) or early mouse embryos exposed to ethanol, resveratrol has been shown to suppress apoptosis and promote survival. However, in cells exposed to genotoxic stress, survival may come at the expense of genome stability. To learn whether resveratrol can protect stem cells from DNA damage and to study its effects on genomic integrity, we exposed mESC pretreated with resveratrol to ionizing radiation (IR). Forty-eight hours pretreatment with a comparatively low concentration of resveratrol (10 μM) improved survival of mESC >2-fold after exposure to 5 Gy of X-rays. Cells pretreated with resveratrol sustained the same levels of reactive oxygen species and DNA strand breakage after IR as mock-treated controls, but repaired DNA damage more rapidly and resumed cell division sooner. Frequencies of IR-induced mutation at a chromosomal reporter locus were not increased in cells pretreated with resveratrol as compared with controls, indicating that resveratrol can improve viability in mESC after DNA damage without compromising genomic integrity.

The potential for chemical mixtures from the environment to enable the cancer hallmark of sustained proliferative signalling.

PubMed

Engström, Wilhelm; Darbre, Philippa; Eriksson, Staffan; Gulliver, Linda; Hultman, Tove; Karamouzis, Michalis V; Klaunig, James E; Mehta, Rekha; Moorwood, Kim; Sanderson, Thomas; Sone, Hideko; Vadgama, Pankaj; Wagemaker, Gerard; Ward, Andrew; Singh, Neetu; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Colacci, Anna Maria; Vaccari, Monica; Mondello, Chiara; Scovassi, A Ivana; Raju, Jayadev; Hamid, Roslida A; Memeo, Lorenzo; Forte, Stefano; Roy, Rabindra; Woodrick, Jordan; Salem, Hosni K; Ryan, Elizabeth P; Brown, Dustin G; Bisson, William H

2015-06-01

The aim of this work is to review current knowledge relating the established cancer hallmark, sustained cell proliferation to the existence of chemicals present as low dose mixtures in the environment. Normal cell proliferation is under tight control, i.e. cells respond to a signal to proliferate, and although most cells continue to proliferate into adult life, the multiplication ceases once the stimulatory signal disappears or if the cells are exposed to growth inhibitory signals. Under such circumstances, normal cells remain quiescent until they are stimulated to resume further proliferation. In contrast, tumour cells are unable to halt proliferation, either when subjected to growth inhibitory signals or in the absence of growth stimulatory signals. Environmental chemicals with carcinogenic potential may cause sustained cell proliferation by interfering with some cell proliferation control mechanisms committing cells to an indefinite proliferative span. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Specific suppression of anti-DNA production in vitro

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

Liebling, M.R.; Wong, C.; Radosevich, J.

1988-09-01

To investigate the regulation of anti-DNA antibody production, we generated anti-DNA-specific suppressor cells by exposing normal human T cells and a small percentage of adherent cells to high concentrations of DNA. These cells suppressed the production of anti-DNA by both autologous peripheral blood mononuclear cells (PBMC) and allogeneic PBMC derived from systemic lupus erythematosus (SLE) patients. Anti-DNA production was suppressed significantly more than anti-RNA, antitetanus, or total immunoglobulin production. Specific suppression was enhanced by increasing the numbers of DNA-primed CD8+ cells and was obliterated by irradiation of the DNA-primed cells. In contrast to T cells from normal individuals, T cellsmore » obtained from two intensively studied SLE patients were unable to generate specific suppressor cells for anti-DNA production in both autologous and allogeneic test systems. Despite this defect, these patients were still capable of generating specific suppressor cells for antibody production directed against an exogenous antigen, tetanus toxoid.« less

Method for rapid isolation of sensitive mutants

DOEpatents

Freyer, James P.

1997-01-01

Sensitive mammalian cell mutants are rapidly isolated using flow cytometry. A first population of clonal spheroids is established to contain both normal and mutant cells. The population may be naturally occurring or may arise from mutagenized cells. The first population is then flow sorted by size to obtain a second population of clonal spheroids of a first uniform size. The second population is then exposed to a DNA-damaging agent that is being investigated. The exposed second population is placed in a growth medium to form a third population of clonal spheroids comprising spheroids of increased size from the mammalian cells that are resistant to the DNA-damaging agent and spheroids of substantially the first uniform size formed from the mammalian cells that are sensitive to the DNA-damaging agent. The third population is not flow sorted to differentiate the spheroids formed from resistant mammalian cells from spheroids formed from sensitive mammalian cells. The spheroids formed from sensitive mammalian cells are now treated to recover viable sensitive cells from which a sensitive cell line can be cloned.

Method for rapid isolation of sensitive mutants

DOEpatents

Freyer, J.P.

1997-07-29

Sensitive mammalian cell mutants are rapidly isolated using flow cytometry. A first population of clonal spheroids is established to contain both normal and mutant cells. The population may be naturally occurring or may arise from mutagenized cells. The first population is then flow sorted by size to obtain a second population of clonal spheroids of a first uniform size. The second population is then exposed to a DNA-damaging agent that is being investigated. The exposed second population is placed in a growth medium to form a third population of clonal spheroids comprising spheroids of increased size from the mammalian cells that are resistant to the DNA-damaging agent and spheroids of substantially the first uniform size formed from the mammalian cells that are sensitive to the DNA-damaging agent. The third population is not flow sorted to differentiate the spheroids formed from resistant mammalian cells from spheroids formed from sensitive mammalian cells. The spheroids formed from sensitive mammalian cells are now treated to recover viable sensitive cells from which a sensitive cell line can be cloned. 15 figs.

Effects of ozone exposure on human epithelial adenocarcinoma and normal fibroblasts cells

PubMed Central

Colafarina, Sabrina; Aruffo, Eleonora; Zarivi, Osvaldo; Bonfigli, Antonella; Di Bucchianico, Sebastiano; Di Carlo, Piero

2017-01-01

Previous studies show variable ozone cytotoxicity and genotoxicity in cell cultures, laboratory animals and humans directly exposed to tropospheric ozone. The aim of this study was therefore to investigate and compare the cyto and genotoxic effects of ozone using adenocarcinoma human alveolar basal epithelial cells A549 and normal human fibroblasts Hs27. A cell culture chamber with controlled atmosphere (a simulation reactor) was built to inject a flow of 120 ppb of ozone, which is two times the threshold value for the protection of human health, fixed by the EU legislation. Cell proliferation was evaluated by a luminescent cell viability assay while we assessed the genotoxic potential of ozone by the induction of micronuclei as well as evaluating DNA strand breaks by the induction of micronuclei evaluated by means of the cytokinesis-block micronucleus (CBMN) assay as well as evaluating DNA strand breaks by Alkaline Comet Assay (CA) or Comet Assay. A549 cells viability decreases significantly at 24 hours treatment with 120 ppb of O3 while at 48 hours and 72 hours O3 treated cells viability doesn’t differ in respect to the control. However a significative decrease of A549 viability is shown at 72 hours vs. 48 hours in both treated and not-treated cells. The viability trend in the Hs27 cells did not show any significant changes in treated samples compared to the control in all conditions. The two genotoxicity biomarkers, the micronucleus and the comet tests, showed in both the cell types exposed to ozone, a significant increase in the number of micronuclei and in the tail DNA % in respect to the control even if at different times/cell type. Moreover, we found that O3 provokes genotoxic effects more evident in A549 cancer cells than in normal fibroblasts Hs27 ones. We applied a cell growth simulation model referred to ozone treated or not cell lines to confirm that the ozone exposure causes a slackening in the cells replication. PMID:28886142

Real time outdoor exposure testing of solar cell modules and component materials

NASA Technical Reports Server (NTRS)

Anagnostou, E.; Forestieri, A. F.

1977-01-01

Plastic samples, solar cell modules, and sub-modules were exposed at test sites in Florida, Arizona, Puerto Rico, and Cleveland, Ohio, in order to determine materials suitable for use in solar cell modules with a proposed 20-year lifetime. Various environments were encountered including subtropical, subtropical with a sea air atmosphere, desert, rain forest, normal urban, and urban-polluted. The samples were exposed for periods up to six months. Materials found not suitable were polyurethane, polyester, Kapton, Mylar, and UV-stabilized Lexan. Suitable materials were acrylic, FEP-A, and glass. The results of exposure of polyvinylidene fluoride were dependent on the specific formulation, but several types appear suitable. RTV silicone rubber (clear) appears to pick up and hold dirt both as a free film and as a potting medium for modules. The results indicate that dirt accumulation and cleanability are important factors in the selection of solar cell module covers and encapsulants.

Shedding Light on the Role of UV Exposure in Melanoma | Center for Cancer Research

Cancer.gov

When a cell is exposed to UV radiation, the chemical makeup of its DNA is changed in a specific manner, resulting in a recognizable modification that can be measured by scientists. These changes are normally detected and fixed by cellular mechanisms for DNA repair. However, if the damage is extensive or if a cell has defective DNA repair machinery, permanent mutations can be

[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.

Peroxisome Proliferator Activated Receptor-α/Hypoxia Inducible Factor-1α Interplay Sustains Carbonic Anhydrase IX and Apoliprotein E Expression in Breast Cancer Stem Cells

PubMed Central

Papi, Alessio; Storci, Gianluca; Guarnieri, Tiziana; De Carolis, Sabrina; Bertoni, Sara; Avenia, Nicola; Sanguinetti, Alessandro; Sidoni, Angelo; Santini, Donatella; Ceccarelli, Claudio; Taffurelli, Mario; Orlandi, Marina; Bonafé, Massimiliano

2013-01-01

Aims Cancer stem cell biology is tightly connected to the regulation of the pro-inflammatory cytokine network. The concept of cancer stem cells “inflammatory addiction” leads to envisage the potential role of anti-inflammatory molecules as new anti-cancer targets. Here we report on the relationship between nuclear receptors activity and the modulation of the pro-inflammatory phenotype in breast cancer stem cells. Methods Breast cancer stem cells were expanded as mammospheres from normal and tumor human breast tissues and from tumorigenic (MCF7) and non tumorigenic (MCF10) human breast cell lines. Mammospheres were exposed to the supernatant of breast tumor and normal mammary gland tissue fibroblasts. Results In mammospheres exposed to the breast tumor fibroblasts supernatant, autocrine tumor necrosis factor-α signalling engenders the functional interplay between peroxisome proliferator activated receptor-α and hypoxia inducible factor-1α (PPARα/HIF1α). The two proteins promote mammospheres formation and enhance each other expression via miRNA130b/miRNA17-5p-dependent mechanism which is antagonized by PPARγ. Further, the PPARα/HIF1α interplay regulates the expression of the pro-inflammatory cytokine interleukin-6, the hypoxia survival factor carbonic anhydrase IX and the plasma lipid carrier apolipoprotein E. Conclusion Our data demonstrate the importance of exploring the role of nuclear receptors (PPARα/PPARγ) in the regulation of pro-inflammatory pathways, with the aim to thwart breast cancer stem cells functioning. PMID:23372804

Mechanism of Lysergic Acid Diethylamide Interference with Rabbit Antibody Biosynthesis

PubMed Central

Voss, Edward W.; Winkelhake, Jeffrey L.

1974-01-01

Lymphoid cells from hyperimmune rabbits producing antibodies to a hapten, incubated in the presence of d-lysergic acid diethylamide, continued to synthesize protein at a normal rate. Isoelectric focusing analysis of the low-molecular-weight protein secreted by the cells incubated with lysergic acid diethylamide indicated two components, with pI's of 4.9 and 5.2. Immune cells not exposed to lysergic acid diethylamide secreted only 7S IgG molecules with an average pI of approximately 7.0. PMID:4524614

Immunocytochemistry and Image Analysis of Beta-Catenin Redistribution in Normal Human Colon Cell Cultures Treated with Disinfection By-Products.

EPA Science Inventory

Epidemiological studies have shown an association between the consumption of chlorinated drinking water and increased risk for colon cancer. In vivo studies proved that rodents exposed to chlorination disinfection byproducts (DBPs) developed aberrant crypt foci (ACF) in t...

Association of Diet With Skin Histological Features in UV-B-Exposed Mice.

PubMed

Bhattacharyya, Tapan K; Hsia, Yvonne; Weeks, David M; Dixon, Tatiana K; Lepe, Jessica; Thomas, J Regan

2017-09-01

Long-term exposure to solar radiation produces deleterious photoaging of the skin. It is not known if diet can influence skin photoaging. To study the influence of a calorie-restricted diet and an obesity diet in mice exposed to long-term UV-B irradiation to assess if there is an association between diet and histopathological response to UV-B irradiation. In this animal model study in an academic setting, the dorsal skin of SKH1 hairless mice receiving normal, calorie-restricted, and obesity diets was exposed to UV-B irradiation 3 times a week for 10 weeks and were compared with corresponding controls. The mice were placed in the following groups, with 8 animals in each group: (1) intact control (C) with regular diet and no UV-B exposure, (2) intact control with UV-B exposure (CR), (3) calorie-restricted diet (CrC), (4) calorie-restricted diet with UV-B exposure (CrR), (5) obesity diet (OC), and (6) obesity diet with UV-B exposure (OR). The experiment was conducted during October through December 2013. Tissue processing and histological analysis were completed in 2016. Histomorphometric analysis was performed on paraffin-embedded skin sections stained by histological and immunohistochemical methods for estimation of epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, mast cells, dermal cellularity, and adipose layer ratio. Changes in wrinkles were noted. Hairless female mice (age range, 6-8 weeks) were obtained. With a normal diet, changes from UV-B irradiation occurred in epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, and mast cells, which were modestly influenced by an obesity diet. Calorie restriction influenced the skin in nonirradiated control animals, with higher values for most variables. After UV-B exposure in animals with calorie restriction, epidermal thickness was increased, but other variables were unaffected. Animals receiving the calorie-restricted diet lost weight when exposed to long-term UV-B irradiation. Wrinkles were reduced in the calorie-restricted control group and in UV-B-exposed animals who received the obesity diet. Dietary alterations seem to modify histopathological responses to UV-B exposure in the skin of hairless mice. NA.

Mechanism of high glucose induced angiotensin II production in rat vascular smooth muscle cells.

PubMed

Lavrentyev, Eduard N; Estes, Anne M; Malik, Kafait U

2007-08-31

Angiotensin II (Ang II), a circulating hormone that can be synthesized locally in the vasculature, has been implicated in diabetes-associated vascular complications. This study was conducted to determine whether high glucose (HG) (approximately 23.1 mmol/L), a diabetic-like condition, stimulates Ang II generation and the underlying mechanism of its production in rat vascular smooth muscle cells. The contribution of various enzymes involved in Ang II generation was investigated by silencing their expression with small interfering RNA in cells exposed to normal glucose (approximately 4.1 mmol/L) and HG. Angiotensin I (Ang I) was generated from angiotensinogen by cathepsin D in the presence of normal glucose or HG. Although HG did not affect the rate of angiotensinogen conversion, it decreased expression of angiotensin-converting enzyme (ACE), downregulated ACE-dependent Ang II generation, and upregulated rat vascular chymase-dependent Ang II generation. The ACE inhibitor captopril reduced Ang II levels in the media by 90% in the presence of normal glucose and 19% in HG, whereas rat vascular chymase silencing reduced Ang II production in cells exposed to HG but not normal glucose. The glucose transporter inhibitor cytochalasin B, the aldose reductase inhibitor alrestatin, and the advanced glycation end product formation inhibitor aminoguanidine attenuated HG-induced Ang II generation. HG caused a transient increase in extracellular signal-regulated kinase (ERK)1/2 phosphorylation, and ERK1/2 inhibitors reduced Ang II accumulation by HG. These data suggest that polyol pathway metabolites and AGE can stimulate rat vascular chymase activity via ERK1/2 activation and increase Ang II production. In addition, decreased Ang II degradation, which, in part, could be attributable to a decrease in angiotensin-converting enzyme 2 expression observed in HG, contributes to increased accumulation of Ang II in vascular smooth muscle cells by HG.

Abdominal Fat and Sarcopenia in Women Significantly Alter Osteoblasts Homeostasis In Vitro by a WNT/β-Catenin Dependent Mechanism

PubMed Central

Wannenes, Francesca; Papa, Vincenza; Greco, Emanuela A.; Fornari, Rachele; Marocco, Chiara; Di Luigi, Luigi; Donini, Lorenzo M.; Lenzi, Andrea

2014-01-01

Obesity and sarcopenia have been associated with mineral metabolism derangement and low bone mineral density (BMD). We investigated whether imbalance of serum factors in obese or obese sarcopenic patients could affect bone cell activity in vitro. To evaluate and characterize potential cellular and molecular changes of human osteoblasts, cells were exposed to sera of four groups of patients: (1) affected by obesity with normal BMD (O), (2) affected by obesity with low BMD (OO), (3) affected by obesity and sarcopenia (OS), and (4) affected by obesity, sarcopenia, and low BMD (OOS) as compared to subjects with normal body weight and normal BMD (CTL). Patients were previously investigated and characterized for body composition, biochemical and bone turnover markers. Then, sera of different groups of patients were used to incubate human osteoblasts and evaluate potential alterations in cell homeostasis. Exposure to OO, OS, and OOS sera significantly reduced alkaline phosphatase, osteopontin, and BMP4 expression compared to cells exposed to O and CTL, indicating a detrimental effect on osteoblast differentiation. Interestingly, sera of all groups of patients induced intracellular alteration in Wnt/β-catenin molecular pathway, as demonstrated by the significant alteration of specific target genes expression and by altered β-catenin cellular compartmentalization and GSK3β phosphorylation. In conclusion our results show for the first time that sera of obese subjects with low bone mineral density and sarcopenia significantly alter osteoblasts homeostasis in vitro, indicating potential detrimental effects of trunk fat on bone formation and skeletal homeostasis. PMID:24963291

Atm heterozygous mice are more sensitive to radiation-induced cataracts than are their wild-type counterparts

NASA Technical Reports Server (NTRS)

Worgul, Basil V.; Smilenov, Lubomir; Brenner, David J.; Junk, Anna; Zhou, Wei; Hall, Eric J.

2002-01-01

It is important to know whether the human population includes genetically predisposed radiosensitive subsets. In vitro studies have shown that cells from individuals homozygous for ataxia telangiectasia (A-T) are much more radiosensitive than cells from unaffected individuals. Although cells heterozygous for the ATM gene (ATM(+/-)) may be slightly more radiosensitive in vitro, it remained to be determined whether the greater susceptibility of ATM(+/-) cells translates into an increased sensitivity for late effects in vivo, though there is a suggestion that radiotherapy patients that are heterozygous for the ATM gene may be more at risk of developing late normal tissue damage. We chose cataractogenesis in the lens as a means to assay for the effects of ATM deficiency in a late-responding tissue. One eye of wild-type, Atm heterozygous and homozygous knockout mice was exposed to 0.5-, 1.0-, 2.0-, or 4.0-Gy x rays. The animals were followed weekly for cataract development by conventional slit-lamp biomicroscopy. Cataract development in the animals of all three groups was strongly dependent on dose. The lenses of homozygous mice were the first to opacify at any given dose. Most important in the present context is that cataracts appeared earlier in the heterozygous versus wild-type animals. The data suggest that ATM heterozygotes in the human population may also be radiosensitive. This may influence the choice of individuals destined to be exposed to higher than normal doses of radiation, such as astronauts, and may also suggest that radiotherapy patients who are ATM heterozygotes could be predisposed to increased late normal tissue damage.

ACTIVE SUPPRESSION OF IMMUNOGLOBULIN ALLOTYPE SYNTHESIS

PubMed Central

Herzenberg, Leonore A.; Chan, Eva L.; Ravitch, Myrnice M.; Riblet, Roy J.; Herzenberg, Leonard A.

1973-01-01

Thymus-derived cells (T cells) that actively suppress production of IgG2a immunoglobulins carrying the Ig-1b allotype have been found in adult (SJL x BALB/c)F1 mice exposed to anti-Ig-1b early in life. The suppression is specific for Ig-1b. The allelic product, Ig-1a, is unaffected. Spleen, lymph node, bone marrow, or thymus cells from suppressed mice suppress production of Ig-1b by syngeneic spleen cells from normal F1 mice. When a mixture of suppressed and normal cells is transferred into lethally irradiated BALB/c mice, there is a short burst of Ig-1b production after which Ig-1b levels in the recipient fall rapidly below detectability. Pretreatment of the cells from the suppressed mice with antiserum specific for T cells (anti-Thy-1b) plus complement before mixture destroys the suppressing activity. Similar results with suppressor cells were obtained in vitro using Mishell-Dutton cultures. Mixture of spleen cells from suppressed animals with sheep erythrocyte (SRBC)-primed syngeneic normal spleen before culture suppresses Ig-1b plaque-forming cell (PFC) formation while leaving Ig-1a PFC unaffected. Treatment of the suppressed spleen with anti-Thy-1b before transfer removes the suppressing activity. PMID:4541122

[Observation of the L929 cell membrane after infrasound exposure with atomic force microscope].

PubMed

Wang, Bing-shui; Chen, Jing-zao; Liu, Bin; Li, Ling; Yi, Nan; Liu, Jing; Zhang, Sa

2005-12-01

To observe the changes of L929 cell membrane with atomic force microscope (AFM) after infrasound exposure and to explore the mechanisms of effect of infrasound on cell membrane. After primary culture, the L929 cells were exposed to infrasound with intensity output of 130 dB and frequency of 16 Hz 2 hours each day for 3 days. The subsequent changes in the membrane of the control cells and the cells exposed to the infrasound were determined by nano-scale scanning with AFM. After infrasound exposure, the normal prominence of the membrane became short and the dent became shallow in the 7.5 microm x 7.5 microm and 4.0 microm x 4.0 microm photographs. The prominence appeared as cobblestones. The surface of the membrane became smooth. The membrane structure of the L929 cells can be changed by infrasound exposure with intensity of 130 dB and frequency of 16 Hz. The change might be one of the characteristics of effect of infrasound on cell membrane.

Genetic changes in progeny of bystander human fibroblasts after microbeam irradiation with X-rays, protons or carbon ions: the relevance to cancer risk.

PubMed

Autsavapromporn, Narongchai; Plante, Ianik; Liu, Cuihua; Konishi, Teruaki; Usami, Noriko; Funayama, Tomoo; Azzam, Edouard I; Murakami, Takeshi; Suzuki, Masao

2015-01-01

Radiation-induced bystander effects have important implications in radiotherapy. Their persistence in normal cells may contribute to risk of health hazards, including cancer. This study investigates the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of harmful effects in progeny of bystander cells. Confluent human skin fibroblasts were exposed to microbeam radiations with different linear energy transfer (LET) at mean absorbed doses of 0.4 Gy by which 0.036-0.4% of the cells were directly targeted by radiation. Following 20 population doublings, the cells were harvested and assayed for micronucleus formation, gene mutation and protein oxidation. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to X-rays (LET ∼6 keV/μm) or protons (LET ∼11 keV/μm) showed persistent oxidative stress, which correlated with increased micronucleus formation and mutation at the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) locus. Such effects were not observed after irradiation by carbon ions (LET ∼103 keV/μm). Interestingly, progeny of bystander cells from cultures exposed to protons or carbon ions under conditions where GJIC was inhibited harbored reduced oxidative and genetic damage. This mitigating effect was not detected when the cultures were exposed to X-rays. These findings suggest that cellular exposure to proton and heavy charged particle with LET properties similar to those used here can reduce the risk of lesions associated with cancer. The ability of cells to communicate via gap junctions at the time of irradiation appears to impact residual damage in progeny of bystander cells.

Ultraviolet- and infrared-induced 11 beta-hydroxysteroid dehydrogenase type 1 activating skin photoaging is inhibited by red ginseng extract containing high concentration of ginsenoside Rg3(S).

PubMed

Nam, Jin-Ju; Min, Ji-Eun; Son, Min-Ho; Oh, Jin-Hwan; Kang, Seunghyun

2017-11-01

Sun irradiation is one of major extrinsic stressors responsible for premature skin aging through activation and expression of 11 beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts inactive cortisone to active cortisol. The aim of this study was to evaluate the inhibitory effects of red ginseng extract containing high concentrations of ginsenoside Rg3 (S) (GERg3) on 11β-HSD1-induced skin photoaging. To evaluate the inhibitory effects of GERg3 on ultraviolet- (UV) or infrared (IR)-induced skin photoaging, human dermal fibroblasts or a normal human 3D skin model was exposed to UV or an IR. RT-PCR, ELISA, Western blot, and H&E staining were used for evaluations. GERg3 was isolated from crude red ginseng. GERg3 inhibited the increased expressions of 11β-HSD1, interleukin (IL)-6, and matrix metalloproteinase-1 (MMP-1) in UVB- or IR-exposed Hs68 cells. Additionally, the increased cortisol, IL-6, and MMP-1 expressions were effectively reduced by GERg3 in UVA-exposed 3D skin models. The photoinduced decrease in type 1 procollagen also recovered as a result of GERg3 treatment in Hs68 cells and the 3D skin model. In addition, the UVA-exposed dermal thickness was decreased in comparison with the UVA-protected 3D skin model, recovered with GERg3 treatment. GERg3 had antiphotoaging effects in UV- or IR-exposed human dermal fibroblasts and normal human 3D skin model. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Early Endothelial Bioactivity of Serum after Diesel Exhaust ...

EPA Pesticide Factsheets

Adverse cardiovascular effects of air pollution are often associated with a spike in systemic proinflammatory biomarkers, but causative linkage between circulating factors and deleterious outcomes following exposure remains elusive. Endothelial dysfunction is a consequence of systemic inflammation and precedes multiple cardiovascular pathologies. The purpose of this study was to examine the plausibility of serum-bound factors as initiators of an air pollution-induced pathologic sequelae beginning with endothelial injury, and later, cardiac dysfunction. We hypothesized that serum taken from diesel exhaust (DE)-exposed rats that develop cardiac dysfunction would alter aortic endothelial cell function in vitro. To assess cardiac function in vivo, left ventricular pressure (LVP) assessments were conducted in rats one day after a single 4 hour whole body exposure to 150 or 500 μg/m3 DE or filtered air. Rat aortic endothelial cells (RAEC) were then exposed to diluted serum (10%) collected 1 hour after exposure from a separate cohort of similarly exposed rats for measures of VCAM-1, cell viability, nitric oxide synthase (NOS) levels, and mRNA expression of key mediators of inflammation. Exposure of rats to 150 or 500 μg/m3 DE increased heart rate (HR) after exposure relative to rats exposed to filtered air, suggesting a shift towards increased sympathetic tone. LVP and HR in DE-exposed rats (500 μg/m3 DE) failed to recover to normal levels after challenge with the

Mechanisms of ozone toxicity in cultured cells. I. Reduced clonogenic ability of polyunsaturated fatty acid-supplemented fibroblasts. Effect of vitamin E

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

Konings, A.W.

1986-01-01

The direct action of ozone on viability and survival of normal and modified mouse lung fibroblasts has been studied. By cell manipulation of fibroblasts in culture, the content of polyunsaturated fatty acids (PUFA) in the phospholipids was increased from about 6% to about 40%. The cellular content of alpha-tocopherol (alpha-T) (vitamin E) could be drastically enhanced. Vitamin E supplementation to the cell did not influence the PUFA manipulation. Normal, PUFA, and PUFA(alpha-T) fibroblasts were exposed to ozone by bubbling 10 ppm through the cell suspensions for different periods of time (0-6 h). No significant effects of the ozone exposure couldmore » be established when normal fibroblasts were used. The PUFA fibroblasts, however, were very vulnerable to ozone toxicity, both in terms of dye uptake (Trypan blue) and cell death (clonogenic ability). When alpha-tocopherol was present in the cell (200 ng/10(6) cells), a clear protection against ozone toxicity was found. It is concluded that ozone toxicity might be higher under conditions of a relative high amount of polyunsaturated fatty acids in the membrane phospholipids of the cell and a low cellular antioxidant capacity. Cellular membranes are probably an important target for ozone-induced cell death.« less

In vivo administration of fluorescent dextrans for the specific and sensitive localization of brain vascular pericytes and their characterization in normal and neurotoxin exposed brains.

PubMed

Sarkar, Sumit; Schmued, Larry

2012-06-01

We have aimed to develop novel histochemical markers for the labeling of brain pericytes and characterize their morphology in the normal and the excitotoxin-exposed brain, as this class of cells has received little attention until recently. Pericyte labeling was accomplished by the intracerebroventricular injection of certain fluorescent dextran conjugates, such as Fluoro-Gold-dextran, FR-dextran, FITC-dextran and Fluoro-Turquoise (FT)-dextran. 1-7 days after the tracer injection, extensive labeling of vascular pericytes was seen throughout the entire brain. These cells were found distal to the endothelial cells and exhibited large dye containing vacuoles. The morphology of the pericytes was somewhat variable, exhibiting round or amoeboid shapes within larger intracellular vesicles, while those wrapping around capillaries exhibited a more elongated appearance with finger-like projections. The use of FG-dextran resulted in bluish yellow fluorescently labeled pericytes, while FR-dextran resulted in red fluorescent labeled pericytes, FITC-dextran exhibited green fluorescent pericytes and FT-dextran showed fluorescent blue pericytes in the brain. We have used these tracers to study possible changes in morphology and pericyte number following kainic acid insult, observing that the number of pericytes in the injured or lesioned areas of the brain is dramatically reduced compared to the non-injured areas. These novel fluorochromes should be of use for studies involving the detection and localization of pericytes in both normal and pathological brain tissues. Published by Elsevier B.V.

Dexmedetomidine Protects Neural Stem Cells from Ketamine-Induced Injury.

PubMed

Lu, Pan; Lei, Shan; Li, Weisong; Lu, Yang; Zheng, Juan; Wang, Ning; Xia, Yongjun; Lu, Haixia; Chen, Xinlin; Liu, Yong; Zhang, Peng-Bo

2018-06-19

Ketamine inhibits the proliferation of neural stem cells (NSCs) and disturbs normal neurogenesis. Dexmedetomidine provides neuroprotection against volatile anesthetic-induced neuroapoptosis and cognitive impairment in the developing brain. Whether it may protect NSCs from ketamine-induced injury remains unknown. In this study, we investigated the protective effects of dexmedetomidine on ketamine-exposed NSCs and explored the mechanisms potentially involved. Primary NSC cultures were characterized using immunofluorescence. Cell viability was determined using a Cell Counting Kit 8 assay. Proliferation and apoptosis were assessed with BrdU incorporation and TUNEL assays, respectively. Protein levels of cleaved caspase-3, phosphorylated protein kinase B (p-Akt), and glycogen synthase kinase-3β (p-GSK-3β) were quantified using western blotting. Ket-amine significantly decreased NSC viability and proliferation and increased their apoptosis. Dexmedetomidine increased NSC proliferation and decreased their apoptosis in a dose-dependent manner. Furthermore, dexmedetomidine pretreatment notably augmented the viability and proliferation of ketamine-exposed NSCs and reduced their apoptosis. Moreover, dexmedetomidine lessened caspase-3 activation and increased p-Akt and p-GSK-3β levels in NSCs exposed to ketamine. The protective effects of dexmedetomidine on ketamine-exposed NSCs could be partly reversed by the PI3K inhibitor LY294002. Collectively, these findings indicate that dexmedetomidine may protect NSCs from ketamine-induced injury via the PI3K/Akt/GSK-3β signaling pathway. © 2018 The Author(s). Published by S. Karger AG, Basel.

Getting to the Outer Leaflet: Physiology of Phosphatidylserine Exposure at the Plasma Membrane.

PubMed

Bevers, Edouard M; Williamson, Patrick L

2016-04-01

Phosphatidylserine (PS) is a major component of membrane bilayers whose change in distribution between inner and outer leaflets is an important physiological signal. Normally, members of the type IV P-type ATPases spend metabolic energy to create an asymmetric distribution of phospholipids between the two leaflets, with PS confined to the cytoplasmic membrane leaflet. On occasion, membrane enzymes, known as scramblases, are activated to facilitate transbilayer migration of lipids, including PS. Recently, two proteins required for such randomization have been identified: TMEM16F, a scramblase regulated by elevated intracellular Ca(2+), and XKR8, a caspase-sensitive protein required for PS exposure in apoptotic cells. Once exposed at the cell surface, PS regulates biochemical reactions involved in blood coagulation, and bone mineralization, and also regulates a variety of cell-cell interactions. Exposed on the surface of apoptotic cells, PS controls their recognition and engulfment by other cells. This process is exploited by parasites to invade their host, and in specialized form is used to maintain photoreceptors in the eye and modify synaptic connections in the brain. This review discusses what is known about the mechanism of PS exposure at the surface of the plasma membrane of cells, how actors in the extracellular milieu sense surface exposed PS, and how this recognition is translated to downstream consequences of PS exposure. Copyright © 2016 the American Physiological Society.

A novel mechanism of acid and bile acid-induced DNA damage involving Na+/H+ exchanger: implication for Barrett's oesophagus.

PubMed

Goldman, Aaron; Shahidullah, Mohammad; Goldman, David; Khailova, Ludmila; Watts, George; Delamere, Nicholas; Dvorak, Katerina

2010-12-01

Barrett's oesophagus is a premalignant disease associated with oesophageal adenocarcinoma. The major goal of this study was to determine the mechanism responsible for bile acid-induced alteration in intracellular pH (pH(i)) and its effect on DNA damage in cells derived from normal oesophagus (HET1A) or Barrett's oesophagus (CP-A). Cells were exposed to bile acid cocktail (BA) and/or acid in the presence/absence of inhibitors of nitric oxide synthase (NOS) or sodium-hydrogen exchanger (NHE). Nitric oxide (NO), pH(i) and DNA damage were measured by fluorescent imaging and comet assay. Expression of NHE1 and NOS in cultured cells and biopsies from Barrett's oesophagus or normal squamous epithelium was determined by RT-PCR, immunoblotting or immunohistochemistry. A dose dependent decrease in pH(i) was observed in CP-A cells exposed to BA. This effect of BA is the consequence of NOS activation and increased NO production, which leads to NHE inhibition. Exposure of oesophageal cells to acid in combination with BA synergistically decreased pH(i). The decrease was more pronounced in CP-A cells and resulted in >2-fold increase in DNA damage compared to acid treatment alone. Examination of biopsies and cell lines revealed robust expression of NHE1 in Barrett's oesophagus but an absence of NHE1 in normal epithelium. The results of this study identify a new mechanism of bile acid-induced DNA damage. We found that bile acids present in the refluxate activate immediately all three isoforms of NOS, which leads to an increased NO production and NHE inhibition. This consequently results in increased intracellular acidification and DNA damage, which may lead to mutations and cancer progression. Therefore, we propose that in addition to gastric reflux, bile reflux should be controlled in patients with Barrett's oesophagus.

Absence of DNA damage after 60-Hz electromagnetic field exposure combined with ionizing radiation, hydrogen peroxide, or c-Myc overexpression.

PubMed

Jin, Yeung Bae; Choi, Seo-Hyun; Lee, Jae Seon; Kim, Jae-Kyung; Lee, Ju-Woon; Hong, Seung-Cheol; Myung, Sung Ho; Lee, Yun-Sil

2014-03-01

The principal objective of this study was to assess the DNA damage in a normal cell line system after exposure to 60 Hz of extremely low frequency magnetic field (ELF-MF) and particularly in combination with various external factors, via comet assays. NIH3T3 mouse fibroblast cells, WI-38 human lung fibroblast cells, L132 human lung epithelial cells, and MCF10A human mammary gland epithelial cells were exposed for 4 or 16 h to a 60-Hz, 1 mT uniform magnetic field in the presence or absence of ionizing radiation (IR, 1 Gy), H(2)O(2) (50 μM), or c-Myc oncogenic activation. The results obtained showed no significant differences between the cells exposed to ELF-MF alone and the unexposed cells. Moreover, no synergistic or additive effects were observed after 4 or 16 h of pre-exposure to 1 mT ELF-MF or simultaneous exposure to ELF-MF combined with IR, H(2)O(2), or c-Myc activation.

Low-level laser therapy (LLLT) reduces oxidative stress in primary cortical neurons in vitro.

PubMed

Huang, Ying-Ying; Nagata, Kazuya; Tedford, Clark E; McCarthy, Thomas; Hamblin, Michael R

2013-10-01

Low-level laser (light) therapy (LLLT) involves absorption of photons being in the mitochondria of cells leading to improvement in electron transport, increased mitochondrial membrane potential (MMP), and greater ATP production. Low levels of reactive oxygen species (ROS) are produced by LLLT in normal cells that are beneficial. We exposed primary cultured murine cortical neurons to oxidative stressors: hydrogen peroxide, cobalt chloride and rotenone in the presence or absence of LLLT (3 J/cm², CW, 810 nm wavelength laser, 20 mW/cm²). Cell viability was determined by Prestoblue™ assay. ROS in mitochondria was detected using Mito-sox, while ROS in cytoplasm was detected with CellRox™. MMP was measured with tetramethylrhodamine. In normal neurons LLLT elevated MMP and increased ROS. In oxidatively-stressed cells LLLT increased MMP but reduced high ROS levels and protected cultured cortical neurons from death. Although LLLT increases ROS in normal neurons, it reduces ROS in oxidatively-stressed neurons. In both cases MMP is increased. These data may explain how LLLT can reduce clinical oxidative stress in various lesions while increasing ROS in cells in vitro. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Survival and characteristics of murine leukaemic and normal stem cells after hyperthermia: a murine model for human bone marrow purging.

PubMed

Gidáli, J; Szamosvölgyi, S; Fehér, I; Kovács, P

1990-01-01

The effect of hyperthermia in vitro on the survival and leukaemogenic effectiveness of WEHI 3-B cells and on the survival and transplantation efficiency of bone marrow cells was compared in a murine model system. Normal murine clonogenic haemopoietic cells (day 9 CFU-S and CFU-GM) proved to be significantly less sensitive to 42.5 degrees C hyperthermia (Do values: 54.3 and 41.1 min, respectively) than leukaemic clonogenic cells (CFU-L) derived from suspension culture or from bone marrow of leukaemic mice (Do: 17.8 min). Exposure for 120 min to 42.5 degrees C reduced the surviving fraction of CFU-L to 0.002 and that of CFU-S to 0.2. If comparable graft sizes were transplanted from normal or heat exposed bone marrow, 60-day survival of supralethally irradiated mice was similar. Surviving WEHI 3-B cells were capable of inducing leukaemia in vivo. The two log difference in the surviving fraction of CFU-L and CFU-S after 120 min exposure to 42.5 degrees C suggests that hyperthermia ex vivo may be a suitable purging method for autologous bone marrow transplantation.

Mitochondrial damage and cytoskeleton reorganization in human dermal fibroblasts exposed to artificial visible light similar to screen-emitted light.

PubMed

Rascalou, Adeline; Lamartine, Jérôme; Poydenot, Pauline; Demarne, Frédéric; Bechetoille, Nicolas

2018-05-05

Artificial visible light is everywhere in modern life. Social communication confronts us with screens of all kinds, and their use is on the rise. We are therefore increasingly exposed to artificial visible light, the effects of which on skin are poorly known. The purpose of this study was to model the artificial visible light emitted by electronic devices and assess its effect on normal human fibroblasts. The spectral irradiance emitted by electronic devices was optically measured and equipment was developed to accurately reproduce such artificial visible light. Effects on normal human fibroblasts were analyzed on human genome microarray-based gene expression analysis. At cellular level, visualization and image analysis were performed on the mitochondrial network and F-actin cytoskeleton. Cell proliferation, ATP release and type I procollagen secretion were also measured. We developed a device consisting of 36 LEDs simultaneously emitting blue, green and red light at distinct wavelengths (450 nm, 525 nm and 625 nm) with narrow spectra and equivalent radiant power for the three colors. A dose of 99 J/cm 2 artificial visible light was selected so as not to induce cell mortality following exposure. Microarray analysis revealed 2984 light-modulated transcripts. Functional annotation of light-responsive genes revealed several enriched functions including, amongst others, the "mitochondria" and "integrin signaling" categories. Selected results were confirmed by real-time quantitative PCR, analyzing 24 genes representing these two categories. Analysis of micro-patterned culture plates showed marked fragmentation of the mitochondrial network and disorganization of the F-actin cytoskeleton following exposure. Functionally, there was considerable impairment of cell growth and spread, ATP release and type I procollagen secretion in exposed fibroblasts. Artificial visible light induces drastic molecular and cellular changes in normal human fibroblasts. This may impede normal cellular functions and contribute to premature skin aging. The present results extend our knowledge of the effects of the low-energy wavelengths that are increasingly used to treat skin disorders. Copyright © 2018 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

SEASONAL VARIATIONS IN AIR POLLUTION PARTICLE-INDUCED INFLAMMATORY MEDIATOR RELEASE AND OXIDATIVE STRESS

EPA Science Inventory

Normal human bronchial epithelial (NHBE) cells and alveolar macrophages (AMs) were exposed to equal mass of coarse [PM with aerodynamic diameter of 2.510 �m (PM2.510)], fine (PM2.5), and ultrafine (PM < 0.1) ambient PM from Chapel Hill, North Carolina, during October 2001 (f...

Characterization of the Differential Response of Endothelial Cells Exposed to Normal and Elevated Laminar Shear Stress

PubMed Central

White, Stephen J; Hayes, Elaine M; Lehoux, Stéphanie; Jeremy, Jamie Y; Horrevoets, Anton JG; Newby, Andrew C

2011-01-01

Most acute coronary events occur in the upstream region of stenotic atherosclerotic plaques that experience laminar shear stress (LSS) elevated above normal physiological levels. Many studies have described the atheroprotective effect on endothelial behavior of normal physiological LSS (approximately 15 dynes/cm2) compared to static or oscillatory shear stress (OSS), but it is unknown whether the levels of elevated shear stress imposed by a stenotic plaque would preserve, enhance or reverse this effect. Therefore we used transcriptomics and related functional analyses to compare human endothelial cells exposed to laminar shear stress of 15 (LSS15-normal) or 75 dynes/cm2 (LSS75-elevated). LSS75 upregulated expression of 145 and downregulated expression of 158 genes more than twofold relative to LSS15. Modulation of the metallothioneins (MT1-G, -M, -X) and NADPH oxidase subunits (NOX2, NOX4, NOX5, and p67phox) accompanied suppression of reactive oxygen species production at LSS75. Shear induced changes in dual specificity phosphatases (DUSPs 1, 5, 8, and 16 increasing and DUSPs 6 and 23 decreasing) were observed as well as reduced ERK1/2 but increased p38 MAP kinase phosphorylation. Amongst vasoactive substances, endothelin-1 expression decreased whereas vasoactive intestinal peptide (VIP) and prostacyclin expression increased, despite which intracellular cAMP levels were reduced. Promoter analysis by rVISTA identified a significant over representation of ATF and Nrf2 transcription factor binding sites in genes upregulated by LSS75 compared to LSS15. In summary, LSS75 induced a specific change in behavior, modifying gene expression, reducing ROS levels, altering MAP kinase signaling and reducing cAMP levels, opening multiple avenues for future study. J. Cell. Physiol. 226: 2841–2848, 2011. © 2011 Wiley-Liss, Inc. PMID:21302282

Correlation between luminescence intensity and cytotoxicity in cell-based cytotoxicity assay using luciferase.

PubMed

Wakuri, S; Yamakage, K; Kazuki, Y; Kazuki, K; Oshimura, M; Aburatani, S; Yasunaga, M; Nakajima, Y

2017-04-01

The luciferase reporter assay has become one of the conventional methods for cytotoxicity evaluation. Typically, the decrease of luminescence expressed by a constitutive promoter is used as an index of cytotoxicity. However, to our knowledge, there have been no reports of the correlation between cytotoxicity and luminescence intensity. In this study, to accurately verify the correlation between them, beetle luciferase was stably expressed in human hepatoma HepG2 cells harboring the multi-integrase mouse artificial chromosome vector. We showed that the cytotoxicity assay using luciferase does not depend on the stability of luciferase protein and the kind of constitutive promoter. Next, HepG2 cells in which green-emitting beetle luciferase was expressed under the control of CAG promoter were exposed to 58 compounds. The luminescence intensity and cytotoxicity curves of cells exposed to 48 compounds showed similar tendencies, whereas those of cells exposed to 10 compounds did not do so, although the curves gradually approached each other with increasing exposure time. Finally, we demonstrated that luciferase expressed under the control of a constitutive promoter can be utilized both as an internal control reporter for normalizing a test reporter and for monitoring cytotoxicity when two kinds of luciferases are simultaneously used in the cytotoxicity assay. Copyright © 2017 Elsevier Inc. All rights reserved.

ANTITOXIN FORMATION BY CELLS TRANSPLANTED TO IRRADIATED ANIMALS

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

Kaulen, D.P.

1963-01-01

The aim of the work was to study, in conditions of normal subcutaneous immunization, which transplanted cells form antitoxin, the significance of the phase of antibody formation, the immunological response of cells to stimulation by 2 unrelated antigens, and to find whether transplanted cells are capable of a secondary immunological response. Donor animals were immunized subcutaneously: guinea pigs twice, with a 30-day interval, with adsorbed diphtheria toxoid, or once with native toxoid; rabbits simultaneously with 2 antigens, the diphtheria toxoid and typhoid formol vaccine, once or several times over 30 days. Recipient animals were exposed to x rays, guinea pigsmore » to 200 or 525 r, and rabbits to 550 or 800 r, and injected intravenously 2 to 4 hr later with cell suspensions prepared from donor spleen, lymphatic nodes, or bone marrow or, for controls, with cells killed by heating. In 3 trials to study the inductive phase of antibody formation, cells were taken from donors 24 hr after single immunization. In guinea pigs exposed to 200 or 525 r and in rabbits to 550 r, there was no sign of anti-diphtheria antitoxin or, in the rabbits, agglutinins during 30 days after transplantation of cells. In 4 trials of antibody production by cells taken in the reproductive phase, all transplanted tissues formed, in up to 10 days, detectable amounts of antitoxin in guinea pigs, except bone marrow in those exposed to 200 r; killed cells produced none. In rabbits exposed to 550 r, transplanted cells formed antibodies to both antigens used; they appeared by the 3rd day, reached a maximum on the 6th, fell rapidly by the 15th, and were not detectable by the 30th day. The pattern was similar for both antigens. Basically the same results were obtained in rabbits exposed to 800 r. When recipient animals were injected with diphtheria toxoid and formol vaccine on the 15th day afier transplantation, no antitoxin was formed but agglutinin titer rose in all animals, even in those injected with killed cells. (OTS)« less

Detection of early changes in lung cell cytology by flow-systems analysis techniques. Progress report, January 1-June 30, 1979

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

Steinkamp, J.A.; Wilson, J.S.; Svitra, Z.V.

1979-08-01

This report summarizes results of ongoing experiments designed to develop automated flow-analysis assay methods for discerning damage to exfoliated respiratory tract cells in model test animals exposed by inhalation to physical and chemical agents associated with the production of synthetic fuels from oil shale and coal, the specific goal being the determination of atypical changes in exposed alveolar macrophages and epithelial cells. Animals were exposed to oil shale particles (raw and spent), silica, and polystyrene latex spheres via intratracheal instillation. Respiratory tract cells were obtained by lavaging the lungs with normal saline, stained with mithramycin for DNA content, and analyzedmore » using flow cytometric analysis methods. In addition to measuring DNA content, differential and total cell counts were made on all samples analyzed. DNA content frequency distribution histograms and cytology showed definite atypical changes resulting from exposure to shale and silica particulates when compared to the controls. To continue development of fluorescence staining methods for measuring intracellular enzymes in alveolar macrophages, studies were initiated for determining ..beta..-glucuronidase using naphthol AS-BI-..beta..-d-glucuronic acid as a fluorogenic substrate. As this new technology becomes adapted to analyzing pulmonary macrophages and epithelial cells, the measurement of physical and biochemical properties as a function of exposure to particulate and gaseous toxic agents related to the production of synthetic fuels will be increased. This analytical approach is designed to assist in the establishment of future guideline for estimating the risks to exposed humans.« less

Biodistribution and photodynamic effects of polyvinylpyrrolidone-hypericin using multicellular spheroids composed of normal human urothelial and T24 transitional cell carcinoma cells

NASA Astrophysics Data System (ADS)

Vandepitte, Joachim; Roelants, Mieke; Cleynenbreugel, Ben Van; Hettinger, Klaudia; Lerut, Evelyne; van Poppel, Hendrik; de Witte, Peter A. M.

2011-01-01

Polyvinylpyrrolidone (PVP)-hypericin is a potent photosensitizer that is used in the urological clinic to photodiagnose with high-sensitivity nonmuscle invasive bladder cancer (NMIBC). We examined the differential accumulation and therapeutic effects of PVP-hypericin using spheroids composed of a human urothelial cell carcinoma cell line (T24) and normal human urothelial (NHU) cells. The in vitro biodistribution was assessed using fluorescence image analysis of 5-μm cryostat sections of spheroids that were incubated with PVP-hypericin. The results show that PVP-hypericin accumulated to a much higher extent in T24 spheroids as compared to NHU spheroids, thereby reproducing the clinical situation. Subsequently, spheroids were exposed to different PDT regimes with a light dose ranging from 0.3 to 18J/cm2. When using low fluence rates, only minor differences in cell survival were seen between normal and malignant spheroids. High light fluence rates induced a substantial difference in cell survival between the two spheroid types, killing ~80% of the cells present in the T24 spheroids. It was concluded that further in vivo experiments are required to fully evaluate the potential of PVP-hypericin as a phototherapeutic for NMIBC, focusing on the combination of the compound with methods that enhance the oxygenation of the urothelium.

Modulation of Differentiation Processes in Murine Embryonic Stem Cells Exposed to Parabolic Flight-Induced Acute Hypergravity and Microgravity.

PubMed

Acharya, Aviseka; Brungs, Sonja; Henry, Margit; Rotshteyn, Tamara; Singh Yaduvanshi, Nirmala; Wegener, Lucia; Jentzsch, Simon; Hescheler, Jürgen; Hemmersbach, Ruth; Boeuf, Helene; Sachinidis, Agapios

2018-06-15

Embryonic developmental studies under microgravity conditions in space are very limited. To study the effects of short-term altered gravity on embryonic development processes, we exposed mouse embryonic stem cells (mESCs) to phases of hypergravity and microgravity and studied the differentiation potential of the cells using wide-genome microarray analysis. During the 64th European Space Agency's parabolic flight campaign, mESCs were exposed to 31 parabolas. Each parabola comprised phases lasting 22 s of hypergravity, microgravity, and a repeat of hypergravity. On different parabolas, RNA was isolated for microarray analysis. After exposure to 31 parabolas, mESCs (P31 mESCs) were further differentiated under normal gravity (1 g) conditions for 12 days, producing P31 12-day embryoid bodies (EBs). After analysis of the microarrays, the differentially expressed genes were analyzed using different bioinformatic tools to identify developmental and nondevelopmental biological processes affected by conditions on the parabolic flight experiment. Our results demonstrated that several genes belonging to GOs associated with cell cycle and proliferation were downregulated in undifferentiated mESCs exposed to gravity changes. However, several genes belonging to developmental processes, such as vasculature development, kidney development, skin development, and to the TGF-β signaling pathway, were upregulated. Interestingly, similar enriched and suppressed GOs were obtained in P31 12-day EBs compared with ground control 12-day EBs. Our results show that undifferentiated mESCs exposed to alternate hypergravity and microgravity phases expressed several genes associated with developmental/differentiation and cell cycle processes, suggesting a transition from the undifferentiated pluripotent to a more differentiated stage of mESCs.

Organization of supercoil domains and their reorganization by transcription

PubMed Central

Deng, Shuang; Stein, Richard A.; Higgins, N. Patrick

2006-01-01

Summary During a normal cell cycle, chromosomes are exposed to many biochemical reactions that require specific types of DNA movement. Separation forces move replicated chromosomes into separate sister cell compartments during cell division, and the contemporaneous acts of DNA replication, RNA transcription and cotranscriptional translation of membrane proteins cause specific regions of DNA to twist, writhe and expand or contract. Recent experiments indicate that a dynamic and stochastic mechanism creates supercoil DNA domains soon after DNA replication. Domain structure is subsequently reorganized by RNA transcription. Examples of transcription-dependent chromosome remodelling are also emerging from eukaryotic cell systems. PMID:16135220

Induction of high mitotic index in Petunia suspension cultures by sequential treatment with aphidicolin and colchicine.

PubMed

Guri, A; Zelcer, A; Izhar, S

1984-12-01

Significantly higher than normal mitotic index (MI) values were induced in Petunia cell suspensions following treatments with colchicine, aphidicolin, drastic medium replacement, or a sequential application of aphidicolin and colchicine. This last treatment yielded the highest MI values: cells incubated with 30 μg/ml aphidicolin for 18 h, then cultured in drug-free medium for 8 h and finally exposed to 0.1% colchicine for 8 additional hours exhibited MI of 62.8% and 65.7% respectively, for the two cell lines in study.

[Correcting influence of vitamin E short chain derivatives on lipid peroxidation, liver cell membrane, and chromatin structure when rats are exposed to embichin].

PubMed

Kovalenko, V M; Byshovets', T F; Hubs'kyĭ, Iu I; Levyts'kyĭ, Ie L; Shaiakhmetova, H M; Marchenko, O M; Voloshyna, O S; Saĭfetdinova, H A; Okhrimenko, V O; Donchenko, H V

2000-01-01

Embikhin causes activation of LPO processes in endoplasmic reticulum and in nuclear chromatine fractions of rat liver cells. The latter is accompanied by the impairment of repressive and active nuclear chromatine fractions structure. Derivate of vitamin E in these conditions renders correcting action on parameters of lipid peroxidation in the investigated subcellular structures, testifying its positive influence on the cell heredity apparatus state. The normalizing action of tocopherol derivative on cytochromes P450 and b5 levels is shown.

Effects of organophosphorus flame retardant TDCPP on normal human corneal epithelial cells: Implications for human health.

PubMed

Xiang, Ping; Liu, Rong-Yan; Li, Chao; Gao, Peng; Cui, Xin-Yi; Ma, Lena Q

2017-11-01

Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is one of the most detected organophosphorus flame retardants (OPFRs) in the environment, especially in indoor dust. Continuous daily exposure to TDCPP-containing dust may adversely impact human cornea. However, its detrimental effects on human corneal epithelium are largely unknown. In this study, we investigated the cell apoptosis in normal human corneal epithelial cells (HCECs) after TDCPP exposure and elucidated the underlying molecular mechanisms. Our data indicated a dose-dependent decrease of cell viability after TDCPP exposure with LC 50 at 202 μg/mL. A concentration-dependent apoptotic sign was observed in HCECs after exposing to ≥2 μg/mL TDCPP. Endoplasmic reticulum stress induction was evidenced by up-regulation of its biomarker genes (ATF-4, CHOP, BiP, and XBP1). Furthermore, alternation of Bcl-2/Bax expression, mitochondrial membrane potential loss, cellular ATP content decrease, and caspase-3 and -9 activity increase were observed after exposing to 2 or 20 μg/mL TDCPP. Taken together, the data implicated the involvement of endoplasmic reticulum stress in TDCPP-induced HCEC apoptosis, probably mediated by mitochondrial apoptotic pathway. Our findings showed TDCPP exposure induced toxicity to human cornea. Due to TDCPP's presence at high levels in indoor dust, further study is warranted to evaluate its health risk on human corneas. Published by Elsevier Ltd.

Suppression of Proinflammatory Cytokines in Functionalized Fullerene-Exposed Dermal Keratinocytes

DOE PAGES

Gao, Jun; Wang, Hsing-Lin; Iyer, Rashi

2010-01-01

Initial experiments using differentially functionalized fullerenes, CD-, hexa-, and tris-, suggested a properties dependent effect on cytotoxic and proliferative responses in human skin keratinocytes. In the present study we investigated the cytokine secretion profile of dermal epithelial cells exposed to functionalized fullerenes. Keratinocyte-derived cytokines affect homing and trafficking of normal and malignant epidermal immune as well as nonimmune cells in vivo. These cytokines are critical for regulating activation, proliferation, and differentiation of epidermal cells. Our results indicate that tris- (size range <100 nm) significantly reduces inflammatory cytokine release in a dose- and time-dependent manner. In contrast CD- demonstrated a relatively pro-inflammatorymore » cytokine response, while hexa- did not significantly perturb cytokine responses. Physical and chemical characterizations of these engineered nanomaterials suggest that the disparate biological responses observed may potentially be a function of the aggregation properties of these fullerenes.« less

Survival, blood osmolality, and gill morphology of juvenile yellow perch, rock bass, black crappie, and largemouth bass exposed to acidified soft water

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

McCormick, J.H.; Jensen, K.M.; Leino, R.L.

1989-01-01

When exposed to a range of pH from 7.0 to 4.0 in soft water (1 mg Ca(2+)/L), juvenile rock bass Ambloplites rupestris, black crappie Pomoxis nigromaculatus, and largemouth bass Micropterus salmoides showed a capacity to osmoregulate and survive for up to 30 d at pH 4.5 and above. Juvenile yellow perch Perca flavescens maintained osmoregulatory control through 58 d at pH 5.0. All four species lost osmoregulatory control at pH 4.0, and death of fish ensued within a few days after blood osmolality declined to about 200 mosmol/kg or less (normal values, about 300 mosmol/kg). After 58 d of exposuremore » of pH 4.0, mean blood osmolality of yellow perch was 218 mosmol/kg, and these fish were severely emaciated and moribund. Rock bass, black crappie, and largemouth bass all died by days 29, 16, and 9, respectively, when exposed to pH 4.0. Examination of gills showed progressively increased pathology with longer exposures to lower than normal pH. Among fish exposed to low pH, gill hyperplasia was present most often, but epithelial hypertrophy, chloride-cell proliferation, chloride-cell degeneration, edema, and vacuolization of the tissues also were observed. Morphological changes that were observed in the three centrarchids at pH values above pH 4.0 suggested that gill pathology may be a more sensitive indicator of potentially lethal acid stress than blood osmolality.« less

Erythrocyte agglutination by wheat germ agglutinin: ionic strength dependence of the contact seam topology.

PubMed

Rolfe, M; Parmar, A; Hoy, T G; Coakley, W T

2001-01-01

The topology of the cell-cell contact seam formed when normal or pronase pre-treated (PPT) erythrocytes are exposed to wheat germ agglutinin (WGA) in isotonic media of different ionic strengths was examined here. Lectin uptake and cell agglutination were also quantified. Agglutination of normal cells was gradually and significantly inhibited as ionic strength (IS) was reduced from 0.15 (buffered 145 mm NaCl) to 0.105. Agglutination was less inhibited in PPT cells, even when IS was reduced to 0.09. Cell contact seams formed during agglutination showed patterns of localized contacts. The scale of the patterns, i.e. the average lateral separation distance of contact regions, was 0.62 microm for normal cells and was significantly shorter, at 0.44 microm, for PPT cells at an IS of 0.15. The scale increased significantly for both cell types when the IS was reduced to 0.09. Flow cytometry measurements showed that WGA uptake by normal cells increased slightly, whilst that for PPT cells was unchanged, as IS was decreased from 0.15 to 0.09. The results imply that, whilst ionic strength change does not exert a strong influence on intermolecular WGA-ligand binding, physico-chemical modification of the interaction between cells modulates not only the extent and progression of the biospecific lectin-induced cell-cell agglutination but also the topology of the contact seam. The IS dependence of contact separation in WGA-agglutinated cells is contrasted here with that reported for cells adhering in dextran solutions. The influence of IS change and pronase pre-treatment on contact pattern are consistent with predictions, from interfacial instability theory, of punctuate thinning of the aqueous layer separating bilayer membranes in close apposition.

CDDO-Me protects normal lung and breast epithelial cells but not cancer cells from radiation.

PubMed

El-Ashmawy, Mariam; Delgado, Oliver; Cardentey, Agnelio; Wright, Woodring E; Shay, Jerry W

2014-01-01

Although radiation therapy is commonly used for treatment for many human diseases including cancer, ionizing radiation produces reactive oxygen species that can damage both cancer and healthy cells. Synthetic triterpenoids, including CDDO-Me, act as anti-inflammatory and antioxidant modulators primarily by inducing the transcription factor Nrf2 to activate downstream genes containing antioxidant response elements (AREs). In the present series of experiments, we determined if CDDO-Me can be used as a radioprotector in normal non-cancerous human lung and breast epithelial cells, in comparison to lung and breast cancer cell lines. A panel of normal non-cancerous, partially cancer progressed, and cancer cell lines from both lung and breast tissue was exposed to gamma radiation with and without pre-treatment with CDDO-Me. CDDO-Me was an effective radioprotector when given ∼18 hours before radiation in epithelial cells (average dose modifying factor (DMF) = 1.3), and Nrf2 function was necessary for CDDO-Me to exert these radioprotective effects. CDDO-Me did not protect cancer lines tested from radiation-induced cytotoxicity, nor did it protect experimentally transformed human bronchial epithelial cells (HBECs) with progressive oncogenic manipulations. CDDO-Me also protected human lymphocytes against radiation-induced DNA damage. A therapeutic window exists in which CDDO-Me protects normal cells from radiation by activating the Nrf2 pathway, but does not protect experimentally transformed or cancer cell lines. This suggests that use of this oral available, non-toxic class of drug can protect non-cancerous healthy cells during radiotherapy, resulting in better outcomes and less toxicity for patients.

CDDO-Me Protects Normal Lung and Breast Epithelial Cells but Not Cancer Cells from Radiation

PubMed Central

El-Ashmawy, Mariam; Delgado, Oliver; Cardentey, Agnelio; Wright, Woodring E.; Shay, Jerry W.

2014-01-01

Although radiation therapy is commonly used for treatment for many human diseases including cancer, ionizing radiation produces reactive oxygen species that can damage both cancer and healthy cells. Synthetic triterpenoids, including CDDO-Me, act as anti-inflammatory and antioxidant modulators primarily by inducing the transcription factor Nrf2 to activate downstream genes containing antioxidant response elements (AREs). In the present series of experiments, we determined if CDDO-Me can be used as a radioprotector in normal non-cancerous human lung and breast epithelial cells, in comparison to lung and breast cancer cell lines. A panel of normal non-cancerous, partially cancer progressed, and cancer cell lines from both lung and breast tissue was exposed to gamma radiation with and without pre-treatment with CDDO-Me. CDDO-Me was an effective radioprotector when given ∼18 hours before radiation in epithelial cells (average dose modifying factor (DMF) = 1.3), and Nrf2 function was necessary for CDDO-Me to exert these radioprotective effects. CDDO-Me did not protect cancer lines tested from radiation-induced cytotoxicity, nor did it protect experimentally transformed human bronchial epithelial cells (HBECs) with progressive oncogenic manipulations. CDDO-Me also protected human lymphocytes against radiation-induced DNA damage. A therapeutic window exists in which CDDO-Me protects normal cells from radiation by activating the Nrf2 pathway, but does not protect experimentally transformed or cancer cell lines. This suggests that use of this oral available, non-toxic class of drug can protect non-cancerous healthy cells during radiotherapy, resulting in better outcomes and less toxicity for patients. PMID:25536195

Regulation of DNA repair in serum-stimulated xeroderma pigmentosum cells

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

Gupta, P.K.; Sirover, M.A.

1984-10-01

The regulation of DNA repair during serum stimulation of quiescent cells was examined in normal human cells, in fibroblasts from three xeroderma pigmentosum complementation groups (A, C, and D), in xeroderma pigmentosum variant cells, and in ataxia telangiectasia cells. The regulation of nucleotide excision repair was examined by exposing cells to ultraviolet irradiation at discrete intervals after cell stimulation. Similarly, base excision repair was quantitated after exposure to methylmethane sulfonate. WI-38 normal human diploid fibroblasts, xeroderma pigmentosum variant cells, as well as ataxia telangiectasia cells enhanced their capacity for both nucleotide excision repair and for base excision repair prior tomore » their enhancement of DNA synthesis. Further, in each cell strain, the base excision repair enzyme uracil DNA glycosylase was increased prior to the induction of DNA polymerase using the identical cells to quantitate each activity. In contrast, each of the three xeroderma complementation groups that were examined failed to increase their capacity for nucleotide excision repair above basal levels at any interval examined. This result was observed using either unscheduled DNA synthesis in the presence of 10 mM hydroxyurea or using repair replication in the absence of hydroxyurea to quantitate DNA repair. However, each of the three complementation groups normally regulated the enhancement of base excision repair after methylmethane sulfonate exposure and each induced the uracil DNA glycosylase prior to DNA synthesis. 62 references, 3 figures, 2 tables.« less

Copper Uptake in Mammary Epithelial Cells Activates Cyclins and Triggers Antioxidant Response

PubMed Central

dos Santos, Nathália Villa; Matias, Andreza Cândido; Higa, Guilherme Shigueto Vilar; Kihara, Alexandre Hiroaki; Cerchiaro, Giselle

2015-01-01

The toxicologic effects of copper (Cu) on tumor cells have been studied during the past decades, and it is suggested that Cu ion may trigger antiproliferative effects in vitro. However, in normal cells the toxicologic effects of high exposures of free Cu are not well understood. In this work, Cu uptake, the expression of genes associated with cell cycle regulation, and the levels of ROS production and related oxidative processes were evaluated in Cu-treated mammary epithelial MCF10A nontumoral cells. We have shown that the Cu additive is associated with the activation of cyclin D1 and cyclin B1, as well as cyclin-dependent kinase 2 (CDK2). These nontumor cells respond to Cu-induced changes in the oxidative balance by increase of the levels of reduced intracellular glutathione (GSH), decrease of reactive oxygen species (ROS) generation, and accumulation during progression of the cell cycle, thus preventing the cell abnormal proliferation or death. Taken together, our findings revealed an effect that contributes to prevent a possible damage of normal cells exposed to chemotherapeutic effects of drugs containing the Cu ion. PMID:26583055

Localized delivery of low-density lipoprotein docosahexaenoic acid nanoparticles to the rat brain using focused ultrasound.

PubMed

Mulik, Rohit S; Bing, Chenchen; Ladouceur-Wodzak, Michelle; Munaweera, Imalka; Chopra, Rajiv; Corbin, Ian R

2016-03-01

Focused ultrasound exposures in the presence of microbubbles can achieve transient, non-invasive, and localized blood-brain barrier (BBB) opening, offering a method for targeted delivery of therapeutic agents into the brain. Low-density lipoprotein (LDL) nanoparticles reconstituted with docosahexaenoic acid (DHA) could have significant therapeutic value in the brain, since DHA is known to be neuroprotective. BBB opening was achieved using pulsed ultrasound exposures in a localized brain region in normal rats, after which LDL nanoparticles containing the fluorescent probe DiR (1,1'-Dioctadecyl-3,3,3',3'-Tetramethylindotricarbocyanine Iodide) or DHA were administered intravenously. Fluorescent imaging of brain tissue from rats administered LDL-DiR demonstrated strong localization of fluorescence signal in the exposed hemisphere. LDL-DHA administration produced 2 × more DHA in the exposed region of the brain, with a corresponding increase in Resolvin D1 levels, indicating DHA was incorporated into cells and metabolized. Histological evaluation did not indicate any evidence of increased tissue damage in exposed brain regions compared to normal brain. This work demonstrates that localized delivery of DHA to the brain is possible using systemically-administered LDL nanoparticles combined with pulsed focused ultrasound exposures in the brain. This technology could be used in regions of acute brain injury or as a means to target infiltrating tumor cells in the brain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Localized Delivery of Low-Density Lipoprotein Docosahexaenoic Acid Nanoparticles to the Rat Brain using Focused Ultrasound

PubMed Central

Mulik, Rohit S.; Bing, Chenchen; Ladouceur-Wodzak, Michelle; Munaweera, Imalka; Chopra, Rajiv; Corbin, Ian R.

2016-01-01

Focused ultrasound exposures in the presence of microbubbles can achieve transient, non-invasive, and localized blood-brain barrier (BBB) opening, offering a method for targeted delivery of therapeutic agents into the brain. Low-density lipoprotein (LDL) nanoparticles reconstituted with docosahexaenoic acid (DHA) could have significant therapeutic value in the brain, since DHA is known to be neuroprotective. BBB opening was achieved using pulsed ultrasound exposures in a localized brain region in normal rats, after which LDL nanoparticles containing the fluorescent probe DiR (1,1′-Dioctadecyl-3,3,3′,3′-Tetramethylindotricarbocyanine Iodide) or DHA were administered intravenously. Fluorescent imaging of brain tissue from rats administered LDL-DiR demonstrated strong localization of fluorescence signal in the exposed hemisphere. LDL-DHA administration produced 2× more DHA in the exposed region of the brain, with a corresponding increase in Resolvin D1 levels, indicating DHA was incorporated into cells and metabolized. Histological evaluation did not indicate any evidence of increased tissue damage in exposed brain regions compared to normal brain. This work demonstrates that localized delivery of DHA to the brain is possible using systemically-administered LDL nanoparticles combined with pulsed focused ultrasound exposures in the brain. This technology could be used in regions of acute brain injury or as a means to target infiltrating tumor cells in the brain. PMID:26790145

C/EBPα expression is downregulated in human nonmelanoma skin cancers and inactivation of C/EBPα confers susceptibility to UVB-induced skin squamous cell carcinomas.

PubMed

Thompson, Elizabeth A; Zhu, Songyun; Hall, Jonathan R; House, John S; Ranjan, Rakesh; Burr, Jeanne A; He, Yu-Ying; Owens, David M; Smart, Robert C

2011-06-01

Human epidermis is routinely subjected to DNA damage induced by UVB solar radiation. Cell culture studies have revealed an unexpected role for C/EBPα (CCAAT/enhancer-binding protein-α) in the DNA damage response network, where C/EBPα is induced following UVB DNA damage, regulates the G(1) checkpoint, and diminished or ablated expression of C/EBPα results in G(1) checkpoint failure. In the current study we observed that C/EBPα is induced in normal human epidermal keratinocytes and in the epidermis of human subjects exposed to UVB radiation. The analysis of human skin precancerous and cancerous lesions (47 cases) for C/EBPα expression was conducted. Actinic keratoses, a precancerous benign skin growth and precursor to squamous cell carcinoma (SCC), expressed levels of C/EBPα similar to normal epidermis. Strikingly, all invasive SCCs no longer expressed detectable levels of C/EBPα. To determine the significance of C/EBPα in UVB-induced skin cancer, SKH-1 mice lacking epidermal C/EBPα (CKOα) were exposed to UVB. CKOα mice were highly susceptible to UVB-induced SCCs and exhibited accelerated tumor progression. CKOα mice displayed keratinocyte cell cycle checkpoint failure in vivo in response to UVB that was characterized by abnormal entry of keratinocytes into S phase. Our results demonstrate that C/EBPα is silenced in human SCC and loss of C/EBPα confers susceptibility to UVB-induced skin SCCs involving defective cell cycle arrest in response to UVB.

C/EBPα Expression Is Downregulated in Human Nonmelanoma Skin Cancers and Inactivation of C/EBPα Confers Susceptibility to UVB-Induced Skin Squamous Cell Carcinomas

PubMed Central

Thompson, Elizabeth A.; Zhu, Songyun; Hall, Jonathan R.; House, John S.; Ranjan, Rakesh; Burr, Jeanne A.; He, Yu-Ying; Owens, David M.; Smart, Robert C.

2012-01-01

Human epidermis is routinely subjected to DNA damage induced by UVB solar radiation. Cell culture studies have revealed an unexpected role for C/EBPα (CCAAT/enhancer-binding protein-α) in the DNA damage response network, where C/EBPα is induced following UVB DNA damage, regulates the G1 checkpoint, and diminished or ablated expression of C/EBPα results in G1 checkpoint failure. In the current study we observed that C/EBPα is induced in normal human epidermal keratinocytes and in the epidermis of human subjects exposed to UVB radiation. The analysis of human skin precancerous and cancerous lesions (47 cases) for C/EBPα expression was conducted. Actinic keratoses, a precancerous benign skin growth and precursor to squamous cell carcinoma (SCC), expressed levels of C/EBPα similar to normal epidermis. Strikingly, all invasive SCCs no longer expressed detectable levels of C/EBPα. To determine the significance of C/EBPα in UVB-induced skin cancer, SKH-1 mice lacking epidermal C/EBPα (CKOα) were exposed to UVB. CKOα mice were highly susceptible to UVB-induced SCCs and exhibited accelerated tumor progression. CKOα mice displayed keratinocyte cell cycle checkpoint failure in vivo in response to UVB that was characterized by abnormal entry of keratinocytes into S phase. Our results demonstrate that C/EBPα is silenced in human SCC and loss of C/EBPα confers susceptibility to UVB-induced skin SCCs involving defective cell cycle arrest in response to UVB. PMID:21346772

GaAs Solar Cell Radiation Handbook

NASA Technical Reports Server (NTRS)

Anspaugh, B. E.

1996-01-01

The handbook discusses the history of GaAs solar cell development, presents equations useful for working with GaAs solar cells, describes commonly used instrumentation techniques for assessing radiation effects in solar cells and fundamental processes occurring in solar cells exposed to ionizing radiation, and explains why radiation decreases the electrical performance of solar cells. Three basic elements required to perform solar array degradation calculations: degradation data for GaAs solar cells after irradiation with 1 MeV electrons at normal incidence; relative damage coefficients for omnidirectional electron and proton exposure; and the definition of the space radiation environment for the orbit of interest, are developed and used to perform a solar array degradation calculation.

Effects of Dracontomelon duperreanum defoliation extract on Microcystis aeruginosa: physiological and morphological aspects.

PubMed

Wang, Xiaoxiong; Jiang, Chenchun; Szeto, Yim-Tong; Li, Ho-Kin; Yam, Kwei-Lam; Wang, Xiaojun

2016-05-01

Harmful cyanobacteria bloom contributes to economic loss as well as the threat to human health. Agricultural waste products, particularly straw, have been used to control bloom while arbor plant is the potential candidate for limiting antialgal activity. This study investigated the use of Dracontomelon duperreanum defoliation extract (DDDE) to inhibit the activity of Microcystis aeruginosa. The primary goal of the research was to explore the solution to control cyanobacterial bloom. The photosynthetic activity, cell morphology, membrane integrity, and esterase activity of M. aeruginosa were determined using phytoplankton analyzer pulse amplitude modulation (Phyto-PAM) and flow cytometry before and after exposure to DDDE. The inhibitory rate of M. aeruginosa was about 99.6 % on day 15 when exposed to 2.0 g L(-1). A reduction of chlorophyll a (Chl-a) activity and changes in cell membrane suggested the algistatic property of DDDE. Inhibition of photosynthetic activity was reflected by changing mean Chl-a fluorescence intensity (MFI) which was about 52.5 % on day 15 when exposed to 2.0 g L(-1) DDDE as well as relative electron transport rates (rETRs) of algal cell. These changes might contribute to the suppression of M. aeruginosa. Algal cell exposed to DDDE may lead to cell volume reduction or slow growth. This resulted in a decreased proportion of normal or swollen granular cells after DDDE treatment.

Effect of 710 nm visible light irradiation on neurite outgrowth in primary rat cortical neurons following ischemic insult

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

Choi, Dong-Hee; Department of Medical Science, Konkuk University School of Medicine, Seoul; Lee, Kyoung-Hee

2012-06-01

Highlights: Black-Right-Pointing-Pointer 710 nm wavelength light (LED) has a protective effect in the stroke animal model. Black-Right-Pointing-Pointer We determined the effects of LED irradiation in vitro stroke model. Black-Right-Pointing-Pointer LED treatment promotes the neurite outgrowth through MAPK activation. Black-Right-Pointing-Pointer The level of synaptic markers significantly increased with LED treatment. Black-Right-Pointing-Pointer LED treatment protects cell death in the in vitro stroke model. -- Abstract: Objective: We previously reported that 710 nm Light-emitting Diode (LED) has a protective effect through cellular immunity activation in the stroke animal model. However, whether LED directly protects neurons suffering from neurodegeneration was entirely unknown. Therefore, wemore » sought to determine the effects of 710 nm visible light irradiation on neuronal protection and neuronal outgrowth in an in vitro stroke model. Materials and methods: Primary cultured rat cortical neurons were exposed to oxygen-glucose deprivation (OGD) and reoxygenation and normal conditions. An LED array with a peak wavelength of 710 nm was placed beneath the covered culture dishes with the room light turned off and were irradiated accordingly. LED treatments (4 min at 4 J/cm{sup 2} and 50 mW/cm{sup 2}) were given once to four times within 8 h at 2 h intervals for 7 days. Mean neurite density, mean neurite diameter, and total fiber length were also measured after microtubule associated protein 2 (MAP2) immunostaining using the Axio Vision program. Synaptic marker expression and MAPK activation were confirmed by Western blotting. Results: Images captured after MAP2 immunocytochemistry showed significant (p < 0.05) enhancement of post-ischemic neurite outgrowth with LED treatment once and twice a day. MAPK activation was enhanced by LED treatment in both OGD-exposed and normal cells. The levels of synaptic markers such as PSD 95, GAP 43, and synaptophysin significantly increased with LED treatment in both OGD-exposed and normal cells (p < 0.05). Conclusion: Our data suggest that LED treatment may promote synaptogenesis through MAPK activation and subsequently protect cell death in the in vitro stroke model.« less

Embryonic Ethanol Exposure Dysregulates BMP and Notch Signaling, Leading to Persistent Atrio-Ventricular Valve Defects in Zebrafish

PubMed Central

Sarmah, Swapnalee; Muralidharan, Pooja

2016-01-01

Fetal alcohol spectrum disorder (FASD), birth defects associated with ethanol exposure in utero, includes a wide spectrum of congenital heart defects (CHDs), the most prevalent of which are septal and conotruncal defects. Zebrafish FASD model was used to dissect the mechanisms underlying FASD-associated CHDs. Embryonic ethanol exposure (3–24 hours post fertilization) led to defects in atrio-ventricular (AV) valvulogenesis beginning around 37 hpf, a morphogenetic event that arises long after ethanol withdrawal. Valve leaflets of the control embryos comprised two layers of cells confined at the compact atrio-ventricular canal (AVC). Ethanol treated embryos had extended AVC and valve forming cells were found either as rows of cells spanning the AVC or as unorganized clusters near the AV boundary. Ethanol exposure reduced valve precursors at the AVC, but some ventricular cells in ethanol treated embryos exhibited few characteristics of valve precursors. Late staged larvae and juvenile fish exposed to ethanol during embryonic development had faulty AV valves. Examination of AVC morphogenesis regulatory networks revealed that early ethanol exposure disrupted the Bmp signaling gradient in the heart during valve formation. Bmp signaling was prominent at the AVC in controls, but ethanol-exposed embryos displayed active Bmp signaling throughout the ventricle. Ethanol exposure also led to mislocalization of Notch signaling cells in endocardium during AV valve formation. Normally, highly active Notch signaling cells were organized at the AVC. In ethanol-exposed embryos, highly active Notch signaling cells were dispersed throughout the ventricle. At later stages, ethanol-exposed embryos exhibited reduced Wnt/β-catenin activity at the AVC. We conclude that early embryonic ethanol exposure alters Bmp, Notch and other signaling activities during AVC differentiation leading to faulty valve morphogenesis and valve defects persist in juvenile fish. PMID:27556898

Embryonic Ethanol Exposure Dysregulates BMP and Notch Signaling, Leading to Persistent Atrio-Ventricular Valve Defects in Zebrafish.

PubMed

Sarmah, Swapnalee; Muralidharan, Pooja; Marrs, James A

2016-01-01

Fetal alcohol spectrum disorder (FASD), birth defects associated with ethanol exposure in utero, includes a wide spectrum of congenital heart defects (CHDs), the most prevalent of which are septal and conotruncal defects. Zebrafish FASD model was used to dissect the mechanisms underlying FASD-associated CHDs. Embryonic ethanol exposure (3-24 hours post fertilization) led to defects in atrio-ventricular (AV) valvulogenesis beginning around 37 hpf, a morphogenetic event that arises long after ethanol withdrawal. Valve leaflets of the control embryos comprised two layers of cells confined at the compact atrio-ventricular canal (AVC). Ethanol treated embryos had extended AVC and valve forming cells were found either as rows of cells spanning the AVC or as unorganized clusters near the AV boundary. Ethanol exposure reduced valve precursors at the AVC, but some ventricular cells in ethanol treated embryos exhibited few characteristics of valve precursors. Late staged larvae and juvenile fish exposed to ethanol during embryonic development had faulty AV valves. Examination of AVC morphogenesis regulatory networks revealed that early ethanol exposure disrupted the Bmp signaling gradient in the heart during valve formation. Bmp signaling was prominent at the AVC in controls, but ethanol-exposed embryos displayed active Bmp signaling throughout the ventricle. Ethanol exposure also led to mislocalization of Notch signaling cells in endocardium during AV valve formation. Normally, highly active Notch signaling cells were organized at the AVC. In ethanol-exposed embryos, highly active Notch signaling cells were dispersed throughout the ventricle. At later stages, ethanol-exposed embryos exhibited reduced Wnt/β-catenin activity at the AVC. We conclude that early embryonic ethanol exposure alters Bmp, Notch and other signaling activities during AVC differentiation leading to faulty valve morphogenesis and valve defects persist in juvenile fish.

Effects of Lycium barbarum Polysaccharides on Apoptosis, Cellular Adhesion, and Oxidative Damage in Bone Marrow Mononuclear Cells of Mice Exposed to Ionizing Radiation Injury

PubMed Central

Zhou, Jing; Pang, Hua; Li, Wenbo; Liu, Qiong; Xu, Lu; Liu, Qian; Liu, Ying

2016-01-01

Lycium barbarum has been used for more than 2500 years as a traditional herb and food in China. We investigated the effects of Lycium barbarum polysaccharides (LBP) on apoptosis, oxidative damage, and expression of adhesion molecules in bone marrow mononuclear cells (BMNC) of mice injured by ionizing radiation. Kunming mice were exposed to X-rays; then mice in the LBP groups were continuously injected with various concentrations of LBP intraperitoneally for 14 days. Mice in the control group were continuously injected with normal saline (NS) by the same route for 14 days. A normal group was set up. After 1, 7, and 14 days of treatment, mice were killed and BMNC were extracted. Cell cycle, apoptosis, and the expression of adhesion molecules CD44 and CD49d were detected by flow cytometry. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were identified by colorimetric analyses. LBP significantly decreased the percentage of G0/G1 phase, apoptosis, MDA level, and expression of CD44 and CD49d and distinctly increased the activity of SOD. LBP showed a protective effect on BMNC against ionizing radiation-induced apoptosis and oxidative damage and altered the expression of adhesion molecule. PMID:27314019

Retinoic acid stability in stem cell cultures.

PubMed

Sharow, Kyle A; Temkin, Boris; Asson-Batres, Mary Ann

2012-01-01

It has been reported that retinoids, such as retinoic acid (RA) and retinol (ROL), dissolved in aqueous solutions are susceptible to oxidative damage when exposed to light, air, and relatively high temperatures, conditions that are normal for culturing stem cells. Thus, questions arise regarding the interpretation of results obtained from studies of mouse embryonic stem cells exposed to retinoids because their isomerization state, their stability in culture conditions, and their interactions with other potential differentiation factors in growth media could influence developmental processes under study. Media samples were supplemented with retinoids and exposed to cell culture conditions with and without mouse embryonic stem cells (mESC), and retinoids were extracted and analyzed using HPLC. To determine whether retinoids are stable in media supplemented with fetal bovine serum (FBS) or in chemically-defined, serum-free media, mESC adapted to each type of growth media were investigated. Studies reported here indicate there was little loss or isomerization of at-RA, 9-cis-RA, 13-cis-RA, or ROL in cell cultures grown in serum-supplemented media when cell cultures were maintained in the dark and manipulated and observed under yellow light. In contrast, the stability of both at-RA and ROL were determined to be greatly reduced in serum-free media as compared with serum-supplemented media. Addition of 6 mg/ml bovine serum albumin was found to stabilize retinoids in serum-free media. It was also determined that ROL is less stable than RA in cell culture conditions.

Atm heterozygous mice are more sensitive to radiation-induced cataracts than are their wild-type counterparts

PubMed Central

Worgul, Basil V.; Smilenov, Lubomir; Brenner, David J.; Junk, Anna; Zhou, Wei; Hall, Eric J.

2002-01-01

It is important to know whether the human population includes genetically predisposed radiosensitive subsets. In vitro studies have shown that cells from individuals homozygous for ataxia telangiectasia (A-T) are much more radiosensitive than cells from unaffected individuals. Although cells heterozygous for the ATM gene (ATM+/−) may be slightly more radiosensitive in vitro, it remained to be determined whether the greater susceptibility of ATM+/− cells translates into an increased sensitivity for late effects in vivo, though there is a suggestion that radiotherapy patients that are heterozygous for the ATM gene may be more at risk of developing late normal tissue damage. We chose cataractogenesis in the lens as a means to assay for the effects of ATM deficiency in a late-responding tissue. One eye of wild-type, Atm heterozygous and homozygous knockout mice was exposed to 0.5-, 1.0-, 2.0-, or 4.0-Gy x rays. The animals were followed weekly for cataract development by conventional slit-lamp biomicroscopy. Cataract development in the animals of all three groups was strongly dependent on dose. The lenses of homozygous mice were the first to opacify at any given dose. Most important in the present context is that cataracts appeared earlier in the heterozygous versus wild-type animals. The data suggest that ATM heterozygotes in the human population may also be radiosensitive. This may influence the choice of individuals destined to be exposed to higher than normal doses of radiation, such as astronauts, and may also suggest that radiotherapy patients who are ATM heterozygotes could be predisposed to increased late normal tissue damage. PMID:12119422

Nrf2 suppresses the function of dendritic cells to facilitate the immune escape of glioma cells.

PubMed

Wang, Jialiang; Liu, Peng; Xin, Shaoyan; Wang, Zongbao; Li, Jun

2017-11-15

Nrf2 is presented in dendritic cells (DCs) and contributes to the maintenance of redox homeostasis. However, the expression pattern and function of Nrf2 in the maturation of DCs in the glioma-infiltrated microenvironment remain unrevealed. Our study aims to investigate the roles of Nrf2 in glioma cell-tamed DCs and their impact on the downstream T cell proliferation and cytotoxicity to glioma cells. It was showed that the inducible maturation of DCs was significantly suppressed after stimulation with tumor-conditioned medium (TCM) prepared from glioma cells (LN-18 and U118MG), as suggested by the decreased CD80, CD86 and IL-12 p70 expression and higher levels of IL-10 than the normal astrocyte medium treated DCs. Moreover, the TCM-exposed DCs had significantly increased expression and transcriptional activity of Nrf2 compared to the negative control. Nrf2 inhibition in DC cells substantially antagonized the inhibitory effects of TCM on the maturation and activation of DC cells, reflected by the elevated maturation markers and IL-12 p70. We further confirmed that Nrf2 inhibition in TCM-exposed DC cells promoted the proliferation of T cells as evaluated by the CFSE-labeled assay and Th1 response shown by the elevated production of IFN-γ. The cytotoxic T lymphocyte assay revealed that Nrf2 genetic suppression in DC cells greatly enhanced the capacity of T cells in the cytotoxicity to glioma cells dependent on the E:T ratio. Collectively, our study demonstrated that Nrf2 inhibition in DCs in glioma-exposed microenvironment could enhance the maturation of DCs and the subsequent activation of T cells and their cytotoxicity on glioma cells. Copyright © 2017. Published by Elsevier Inc.

Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in the endometrium of patients with repeated implantation failure after in vitro fertilization.

PubMed

Turgut, A; Goruk, N Y; Tunc, S Y; Agaçayak, E; Alabalik, U; Yalinkaya, A; Gül, T

2014-01-01

To compare the immunohistochemical expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in repeated implantation failure (RIF) patients with normal fertile controls. The study group consisted of primary infertile patients with RIF and normal fertile controls between January 2011 and February 2013. Endometrial samples received at the luteal phase were exposed to immunohistochemical staining for EMMPRIN antibodies. EMMPRIN expression of endometrial glandular epithelial cells, stromal cells and vascular endothelial cells were evaluated. The main outcome measure was defined as immunohistochemical score with regard to the severity and extent of staining. The study group consisted of 26 primary infertile patients, whereas the control group consisted of 40 normal fertile controls. The fertile group was found to have stronger expression of EMMPRIN than the study group when endometrial glandular epithelial cells, stromal cells and vascular endothelial cells were evaluated with regards to the severity of staining (p < 0.001), the extent of staining (p < 0.001) and total staining score (p < 0.001). This is the first study showing low expression of EMMPRIN in the endometrial cells of the patients with RIF compared with fertile healthy controls. We suggest that reduced EMMPRIN expression in the human endometrium may lead to poor endometrial receptivity.

Endotracheal aerosolization of atropine sulfate protects against soman-induced acute respiratory toxicity in guinea pigs.

PubMed

Perkins, Michael W; Pierre, Zdenka; Rezk, Peter; Song, Jian; Marshall, Seema; Oguntayo, Samuel; Morthole, Venee; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2011-03-01

The efficacy of endotracheal aerosolization of atropine sulfate for protection against soman (GD)-induced respiratory toxicity was investigated using microinstillation technique in guinea pigs. GD (841 mg/m(3), 1.3 LCt(50) or 1121 mg/m(3), 1.7 LCt(50)) was aerosolized endotracheally to anesthetized male guinea pigs that were treated with atropine sulfate (5.0 mg/kg) 30 s postexposure by endotracheal microinstillation. Animals exposed to 841 mg/m(3) and 1121 mg/m(3)GD resulted in 31 and 13% while treatment with atropine sulfate resulted in 100 and 50% survival, respectively. Cholinergic symptoms and increased body weight loss were reduced in atropine-treated animals compared to GD controls. Diminished pulse rate and blood O(2) saturation in GD-exposed animals returned to normal levels after atropine treatment. Increased cell death, total cell count and protein in the bronchoalveolar fluid (BALF) in GD-exposed animals returned to normal levels following atropine treatment. GD exposure increased glutathione and superoxide dismutase levels in BALF and that were reduced in animals treated with atropine. Respiratory parameters measured by whole-body barometric plethysmography revealed that treatment with atropine sulfate resulted in normalization of respiratory frequency, tidal volume, time of expiration, time of inspiration, end expiratory pause, pseudo lung resistance (Penh) and pause at 4 and 24 h post 841 mg/m(3) GD exposure. Lung histopathology showed that atropine treatment reduced bronchial epithelial subepithelial inflammation and multifocal alveolar septal edema. These results suggest that endotracheal aerosolization of atropine sulfate protects against respiratory toxicity and lung injury induced by microinstillation inhalation exposure to lethal doses of GD.

Nontargeted stressful effects in normal human fibroblast cultures exposed to low fluences of high charge, high energy (HZE) particles: kinetics of biologic responses and significance of secondary radiations.

PubMed

Gonon, Géraldine; Groetz, Jean-Emmanuel; de Toledo, Sonia M; Howell, Roger W; Fromm, Michel; Azzam, Edouard I

2013-04-01

The induction of nontargeted stressful effects in cell populations exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation. We investigated the up-regulation of stress markers in confluent normal human fibroblast cultures exposed to 1,000 MeV/u iron ions [linear energy transfer (LET) ∼151 keV/μm] or 600 MeV/u silicon ions (LET ∼50 keV/μm) at mean absorbed doses as low as 0.2 cGy, wherein 1-3% of the cells were targeted through the nucleus by a primary particle. Within 24 h postirradiation, significant increases in the levels of phospho-TP53 (serine 15), p21(Waf1) (CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation were detected, which suggested participation in the stress response of cells not targeted by primary particles. This was supported by in situ studies that indicated greater increases in 53BP1 foci formation, a marker of DNA damage. than expected from the number of primary particle traversals. The effect was expressed as early as 15 min after exposure, peaked at 1 h and decreased by 24 h. A similar tendency occurred after exposure of the cell cultures to 0.2 cGy of 3.7 MeV α particles (LET ∼109 keV/μm) that targets ∼1.6% of nuclei, but not after 0.2 cGy from 290 MeV/u carbon ions (LET ∼13 keV/μm) by which, on average, ∼13% of the nuclei were hit, which highlights the importance of radiation quality in the induced effect. Simulations with the FLUKA multi-particle transport code revealed that fragmentation products, other than electrons, in cell cultures exposed to HZE particles comprise <1% of the absorbed dose. Further, the radial spread of dose due to secondary heavy ion fragments is confined to approximately 10-20 μm. Thus, the latter are unlikely to significantly contribute to stressful effects in cells not targeted by primary HZE particles.

A natural protective mechanism against hyperglycaemia in vascular endothelial and smooth-muscle cells: role of glucose and 12-hydroxyeicosatetraenoic acid.

PubMed Central

Alpert, Evgenia; Gruzman, Arie; Totary, Hanan; Kaiser, Nurit; Reich, Reuven; Sasson, Shlomo

2002-01-01

Bovine aortic endothelial and smooth-muscle cells down-regulate the rate of glucose transport in the face of hyperglycaemia, thus providing protection against deleterious effects of increased intracellular glucose levels. When exposed to high glucose concentrations these cells reduced the mRNA and protein content of their typical glucose transporter, GLUT-1, as well as its plasma-membrane abundance. Inhibition of the lipoxygenase (LO) pathway, and particularly 12-LO, reversed this glucose-induced down-regulatory process and restored the rate of hexose transport to the level seen in vascular cells exposed to normal glucose levels. This reversal was accompanied by increased levels of GLUT-1 mRNA and protein, as well as of its plasma-membrane content. Exposure of the vascular cells to elevated glucose concentrations increased by 2-3-fold the levels of cell-associated and secreted 12-hydroxyeicosatetraenoic acid (12-HETE), the product of 12-LO. Inhibition of 15- and 5-LO, cyclo-oxygenases 1 and 2, and eicosanoid-producing cytochrome P450 did not modify the hexose-transport system in vascular cells. These results suggest a role for HETEs in the autoregulation of hexose transport in vascular cells. 8-Iso prostaglandin F(2alpha), a non-enzymic oxidation product of arachidonic acid, had no effect on the hexose-transport system in vascular cells exposed to hyperglycaemic conditions. Taken together, these findings show that hyperglycaemia increases the production rate of 12-HETE, which in turn mediates the down-regulation of GLUT-1 expression and the glucose-transport system in vascular endothelial and smooth-muscle cells. PMID:11853550

Diphtheria toxin translocation across cellular membranes is regulated by sphingolipids

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

Spilsberg, Bjorn; Hanada, Kentaro; Sandvig, Kirsten

2005-04-08

Diphtheria toxin is translocated across cellular membranes when receptor-bound toxin is exposed to low pH. To study the role of sphingolipids for toxin translocation, both a mutant cell line lacking the first enzyme in de novo sphingolipid synthesis, serine palmitoyltransferase, and a specific inhibitor of the same enzyme, myriocin, were used. The serine palmitoyltransferase-deficient cell line (LY-B) was found to be 10-15 times more sensitive to diphtheria toxin than the genetically complemented cell line (LY-B/cLCB1) and the wild-type cell line (CHO-K1), both when toxin translocation directly across the plasma membrane was induced by exposing cells with surface-bound toxin to lowmore » pH, and when the toxin followed its normal route via acidified endosomes into the cytosol. Toxin binding was similar in these three cell lines. Furthermore, inhibition of serine palmitoyltransferase activity by addition of myriocin sensitized the two control cell lines (LY-B/cLCB1 and CHO-K1) to diphtheria toxin, whereas, as expected, no effect was observed in cells lacking serine palmitoyltransferase (LY-B). In conclusion, diphtheria toxin translocation is facilitated by depletion of membrane sphingolipids.« less

Role of gap junction intercellular communication in testicular leydig cell apoptosis induced by oxaliplatin via the mitochondrial pathway.

PubMed

Tong, Xuhui; Han, Xi; Yu, Binbin; Yu, Meiling; Jiang, Guojun; Ji, Jie; Dong, Shuying

2015-01-01

Platinum agents are widely used in the chemotherapy of testicular cancer. However, adverse reactions and resistance to such agents have limited their application in antineoplastic treatment. The aim of the present study was to determine the role of gap junction intercellular communication (GJIC) composed of Cx43 on oxaliplatin‑induced survival/apoptosis in mouse leydig normal and cancer cells using MTT, Annexin V/PI double staining assays and western blot analysis. The results showed that GJIC exerted opposite effects on the mouse leydig cancer (I-10) and normal (TM3) cell apoptosis induced by oxaliplatin. In leydig cancer cells, survival of cells exposed to oxaliplatin was substantially reduced when gap junctions formed as compared to no gap junctions. Pharmacological inhibition of gap junctions by oleamide and 18-α-glycyrrhetinic acid resulted in enhanced survival/decreased apoptosis while enhancement of gap junctions by retinoic acid led to decreased survival/increased apoptosis. These effects occurred only in high‑density cultures (gap junction formed), while the pharmacological modulations had no effects when there was no opportunity for gap junction formation. Notably, GJIC played an opposite (protective) role in normal leydig cells survival/apoptosis following exposure to oxaliplatin. Furthermore, this converse oxaliplatin‑inducing apoptosis exerted through the functional gap junction was correlated with the mitochondrial pathway‑related protein Bcl-2/Bax and caspase‑3/9. These results suggested that in testicular leydig normal/cancer cells, GJIC plays an opposite role in oxaliplatin‑induced apoptosis via the mitochondrial pathway.

Chemical Carcinogen (Hydrazine, Polynuclear Hydrocarbon and/or Synthetic Jet Fuel Components) Induced Carcinogenesis of Human Cells, In Vitro

DTIC Science & Technology

1981-08-01

Various levels of DNA repair synthesis in Xeroderma pigmenrosum cells exposed to the carcinogens N-hydroxy and N-acetoxy-2-acetylsminofluorene...Nature (New Biol.). 238 (1972) 9. 5 V.M Maher, N. Birch, J.R. Otto and J. McCormick, Cytotoxicity of carcinogenic aro- matic amides in normal and Xeroderma ... pigmentosum fibroblasts with different DNA repair capabilities, J. Nati. Cancer Inst., 54 (1975) 1287. 6 R.H. Heflich, R.M. Hazard, L. Lommnel, J.D

[Elevated expression of endothelin 2 in lung tissues of asthmatic rats after exposed to cigarette smoke and its mechanism].

PubMed

Han, Fangfang; Zhu, Shuyang; Chen, Bi; Li, Jingjing

2017-08-01

Objective To study the effect of cigarette smoke exposure on the expression of endothelin 2 (ET-2) in bronchial epithelium of asthmatic rats. Methods Asthma models were established through intraperitoneal injection of 1 mL chicken ovalbumin (OVA)/Al(OH) 3 mixture (asthma model group, n=6); based on the asthma models, exposure to smoking gas lasted four weeks with 10 cigarettes per day (smoke-exposed asthma group, n=6); based on the smoke-exposed asthma models, the rats were treated with intraperitoneal injection of dexamethasone 2 mg/(kg.d), intragastric administration of ET receptor inhibitor bosentan 100 mg/(kg.d) and combined use, respectively named dexamethasone treated group, bosentan treated group, and dexamethasone-bosentan treated group, 6 rats in every group. What's more, other 6 rats were only subjected to intraperitoneal injection of 1 mL normal saline as normal controls; in addition to the injection of saline, cigarette smoke control group (n=6) was set up by the exposure to smoking gas for four weeks with 10 cigarettes per day. Bronchoalveolar lavage fluid (BALF) was collected from the upper lobe of the left lung for cell counting and classification. Pathological changes of the right upper lung lobe tissues were observed by HE staining. In other lung tissues, the expression of JNK1/2 was detected by Western blotting; ET-2 was tested by Western blotting and immunohistochemistry; thiobarbituric acid reactive substances (TBARS) assay and trace enzyme standard method were used to measure malondialdehyde (MDA) and glutathione (GSH), respectively. Results Compared with normal control group, the number of airway inflammation cells increased in the BALF, and the expressions of ET-2, JNK1/2, MDA and GSH increased in the lung tissues of cigarette smoke control group, asthma model group and cigarette smoke-exposed asthma group. Compared with cigarette smoke-exposed asthma group, the number of airway inflammation cells decreased in the BALF, and the expressions of ET-2, JNK1/2, MDA and GSH decreased in the lung tissues of the dexamethasone treated group, bosentan treated group, and dexamethasone-bosentan treated group. Airway inflammation was attenuated and the staining intensity of ET-2 in the lung tissue was reduced in the dexamethasone treated group, bosentan treated group, and dexamethasone-bosentan treated group, which were more obvious in the dexamethasone-bosentan treated group. Conclusion Cigarette smoke exposure obviously aggravates airway inflammation in asthmatic rats, and bosentan can effectively alleviate the airway inflammation. The mechanism of the inflammation may be related to ET-2 and JNK1/2 signaling pathway.

Association of Diet With Skin Histological Features in UV-B–Exposed Mice

PubMed Central

Hsia, Yvonne; Weeks, David M.; Dixon, Tatiana K.; Lepe, Jessica; Thomas, J. Regan

2017-01-01

Importance Long-term exposure to solar radiation produces deleterious photoaging of the skin. It is not known if diet can influence skin photoaging. Objectives To study the influence of a calorie-restricted diet and an obesity diet in mice exposed to long-term UV-B irradiation to assess if there is an association between diet and histopathological response to UV-B irradiation. Design, Setting, and Participants In this animal model study in an academic setting, the dorsal skin of SKH1 hairless mice receiving normal, calorie-restricted, and obesity diets was exposed to UV-B irradiation 3 times a week for 10 weeks and were compared with corresponding controls. The mice were placed in the following groups, with 8 animals in each group: (1) intact control (C) with regular diet and no UV-B exposure, (2) intact control with UV-B exposure (CR), (3) calorie-restricted diet (CrC), (4) calorie-restricted diet with UV-B exposure (CrR), (5) obesity diet (OC), and (6) obesity diet with UV-B exposure (OR). The experiment was conducted during October through December 2013. Tissue processing and histological analysis were completed in 2016. Main Outcomes and Measures Histomorphometric analysis was performed on paraffin-embedded skin sections stained by histological and immunohistochemical methods for estimation of epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, mast cells, dermal cellularity, and adipose layer ratio. Changes in wrinkles were noted. Results Hairless female mice (age range, 6-8 weeks) were obtained. With a normal diet, changes from UV-B irradiation occurred in epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, and mast cells, which were modestly influenced by an obesity diet. Calorie restriction influenced the skin in nonirradiated control animals, with higher values for most variables. After UV-B exposure in animals with calorie restriction, epidermal thickness was increased, but other variables were unaffected. Animals receiving the calorie-restricted diet lost weight when exposed to long-term UV-B irradiation. Wrinkles were reduced in the calorie-restricted control group and in UV-B–exposed animals who received the obesity diet. Conclusions and Relevance Dietary alterations seem to modify histopathological responses to UV-B exposure in the skin of hairless mice. Level of Evidence NA. PMID:28418519

Secondhand Smoke Exposure Reduced the Compensatory Effects of IGF-I Growth Signaling in the Aging Rat Hearts

PubMed Central

Wu, Jia-Ping; Hsieh, Dennis Jine-Yuan; Kuo, Wei-Wen; Han, Chien-Kuo; Pai, Peiying; Yeh, Yu-Lan; Lin, Chien-Chung; Padma, V. Vijaya; Day, Cecilia Hsuan; Huang, Chih-Yang

2015-01-01

Background: Secondhand smoke (SHS) exposure is associated with increased risk of cardiovascular disease. Aging is a physiological process that involves progressive impairment of normal heart functions due to increased vulnerability to damage. This study examines secondhand smoke exposure in aging rats to determine the age-related death-survival balance. Methods: Rats were placed into a SHS exposure chamber and exposed to smog. Old age male Sprague-Dawley rats were exposed to 10 cigarettes for 30 min, day and night, continuing for one week. After 4 weeks the rats underwent morphological and functional studies. Left ventricular sections were stained with hematoxylin-eosin for histopathological examination. TUNEL detected apoptosis cells and protein expression related death and survival pathway were analyzed using western blot. Results: Death receptor-dependent apoptosis upregulation pathways and the mitochondria apoptosis proteins were apparent in young SHS exposure and old age rats. These biological markers were enhanced in aging SHS-exposed rats. The survival pathway was found to exhibit compensation only in young SHS-exposed rats, but not in the aging rats. Further decrease in the activity of this pathway was observed in aging SHS-exposed rats. TUNEL apoptotic positive cells were increased in young SHS-exposed rats, and in aging rats with or without SHS-exposure. Conclusions: Aging reduces IGF-I compensated signaling with accelerated cardiac apoptotic effects from second-hand smoke. PMID:26392808

Urea impairs β cell glycolysis and insulin secretion in chronic kidney disease

PubMed Central

Koppe, Laetitia; Nyam, Elsa; Vivot, Kevin; Manning Fox, Jocelyn E.; Dai, Xiao-Qing; Nguyen, Bich N.; Attané, Camille; Moullé, Valentine S.; MacDonald, Patrick E.; Ghislain, Julien

2016-01-01

Disorders of glucose homeostasis are common in chronic kidney disease (CKD) and are associated with increased mortality, but the mechanisms of impaired insulin secretion in this disease remain unclear. Here, we tested the hypothesis that defective insulin secretion in CKD is caused by a direct effect of urea on pancreatic β cells. In a murine model in which CKD is induced by 5/6 nephrectomy (CKD mice), we observed defects in glucose-stimulated insulin secretion in vivo and in isolated islets. Similarly, insulin secretion was impaired in normal mouse and human islets that were cultured with disease-relevant concentrations of urea and in islets from normal mice treated orally with urea for 3 weeks. In CKD mouse islets as well as urea-exposed normal islets, we observed an increase in oxidative stress and protein O-GlcNAcylation. Protein O-GlcNAcylation was also observed in pancreatic sections from CKD patients. Impairment of insulin secretion in both CKD mouse and urea-exposed islets was associated with reduced glucose utilization and activity of phosphofructokinase 1 (PFK-1), which could be reversed by inhibiting O-GlcNAcylation. Inhibition of O-GlcNAcylation also restored insulin secretion in both mouse models. These results suggest that insulin secretory defects associated with CKD arise from elevated circulating levels of urea that increase islet protein O-GlcNAcylation and impair glycolysis. PMID:27525435

The effect of serum on monocyte tissue factor generation.

PubMed

Edwards, R L; Perla, D

1984-09-01

Human monocytes generate the procoagulant tissue factor (MTF) following exposure to a variety of immune stimuli in vitro. The generation of MTF is modified by T cells, lymphokines, and immunoregulatory lipoproteins, and recent studies have shown that MTF can be activated in an immune-specific manner following exposure to antigen. We have examined the role of serum factors in the regulation of MTF generation. Low concentrations (less than 1%) of heat-inactivated normal human serum greatly enhanced MTF generation in cultures of normal peripheral blood mononuclear cells. The stimulatory effect was observed in cultures of both unstimulated cells and cells exposed to bacterial lipopolysaccharide. Stimulation was not observed at high serum concentrations (greater than 10%) and could not be explained by endotoxin contamination or activation of the assay system. Stimulatory activity was present in plasma and BaSO4-adsorbed plasma as well as autologous and allogeneic serum, was not abolished by removal of serum lipoproteins, and did not require the presence of T cells for its expression. Sera from 28 different normal volunteers were screened for stimulatory activity and demonstrated a wide variation in potency. These results suggest that a potent factor is present in sera that enhances the expression of MTF activity in vitro. This factor is distinct from previously described lipoprotein regulators and may play a role in the initiation of coagulation in both normal hemostasis and pathologic states.

Effects on micronuclei formation of 60-Hz electromagnetic field exposure with ionizing radiation, hydrogen peroxide, or c-Myc overexpression.

PubMed

Jin, Yeung Bae; Kang, Ga-Young; Lee, Jae Seon; Choi, Jong-Il; Lee, Ju-Woon; Hong, Seung-Cheol; Myung, Sung Ho; Lee, Yun-Sil

2012-04-01

Epidemiological studies have demonstrated a possible correlation between exposure to extremely low-frequency magnetic fields (ELF-MF) and cancer. However, this correlation has yet to be definitively confirmed by epidemiological studies. The principal objective of this study was to assess the effects of 60 Hz magnetic fields in a normal cell line system, and particularly in combination with various external factors, via micronucleus (MN) assays. Mouse embryonic fibroblast NIH3T3 cells and human lung fibroblast WI-38 cells were exposed for 4 h to a 60 Hz, 1 mT uniform magnetic field with or without ionizing radiation (IR, 2 Gy), H(2)O(2) (100 μM) and cellular myelocytomatosis oncogene (c-Myc) activation. The results obtained showed no significant differences between the cells exposed to ELF-MF alone and the unexposed cells. Moreover, no synergistic effects were observed when ELF-MF was combined with IR, H(2)O(2), and c-Myc activation. Our results demonstrate that ELF-MF did not enhance MN frequency by IR, H(2)O(2) and c-Myc activation.

Proinflammatory effects of cookstove emissions on human bronchial epithelial cells.

PubMed

Hawley, B; Volckens, J

2013-02-01

Approximately half of the world's population uses biomass fuel for indoor cooking and heating. This form of combustion typically occurs in open fires or primitive stoves. Human exposure to emissions from indoor biomass combustion is a global health concern, causing an estimated 1.5 million premature deaths each year. Many 'improved' stoves have been developed to address this concern; however, studies that examine exposure-response with cleaner-burning, more efficient stoves are few. The objective of this research was to evaluate the effects of traditional and cleaner-burning stove emissions on an established model of the bronchial epithelium. We exposed well-differentiated, normal human bronchial epithelial cells to emissions from a single biomass combustion event using either a traditional three-stone fire or one of two energy-efficient stoves. Air-liquid interface cultures were exposed using a novel, aerosol-to-cell deposition system. Cellular expression of a panel of three pro-inflammatory markers was evaluated at 1 and 24 h following exposure. Cells exposed to emissions from the cleaner-burning stoves generated significantly fewer amounts of pro-inflammatory markers than cells exposed to emissions from a traditional three-stone fire. Particulate matter emissions from each cookstove were substantially different, with the three-stone fire producing the largest concentrations of particles (by both number and mass). This study supports emerging evidence that more efficient cookstoves have the potential to reduce respiratory inflammation in settings where solid fuel combustion is used to meet basic domestic needs. Emissions from more efficient, cleaner-burning cookstoves produced less inflammation in well-differentiated bronchial lung cells. The results support evidence that more efficient cookstoves can reduce the health burden associated with exposure to indoor pollution from the combustion of biomass. © 2012 John Wiley & Sons A/S.

Pulmonary response to inhaled Kevlar aramid synthetic fibers in rats.

PubMed

Lee, K P; Kelly, D P; Kennedy, G L

1983-11-01

Groups of male rats were exposed to specially prepared ultrafine Kevlar pulp fibers (du Pont's registered trademark for certain aramid fibers) at atmospheric concentrations of either 0.1, 0.5, 3.0, or 18 mg/m3 for 2 weeks. Rats were killed at 0 and 2 weeks and 3 and 6 months postexposure (PE) except the rats exposed to 18 mg/m3, which were killed 0, 4, and 14 days and 1, 3, and 6 months PE. Another group of male rats was exposed to 18 mg/m3 (respirable dust approximately 2.5 mg/m3) of commercial Kevlar fibers for 2 weeks and were killed at 0 and 2 weeks and 3 and 6 months PE. Inhaled ultrafine Kevlar fibers were mostly phagocytized by alveolar macrophages (dust cells) in the alveolar ducts and adjoining alveoli after exposure to either 0.1 or 0.5 micrograms/m3. Most dust cells had disappeared and lungs showed a normal appearance throughout 6 months PE. The pulmonary response almost satisfied the biological criteria for a nuisance dust. Rats exposed to 3 mg/m3 ultrafine Kevlar fibers revealed occasional patchy thickening of alveolar ducts with dust cells and inflammatory cells but with no collagen fibers deposited throughout 6 months PE. After exposure to 18 mg/m3 ultrafine Kevlar, the respiratory bronchioles, alveolar ducts, and adjoining alveoli showed granulomatous lesions with dust cells by 2 weeks PE. The granulomatous lesions converted to patchy fibrotic thickening with dust cells after 1 month PE. The fibrotic lesions were markedly reduced in cellularity, size, and numbers from 3 to 6 months PE but revealed networks of reticulum fibers with slight collagen fiber deposition.

Influence of local anesthetics upon human polymorphonuclear leukocyte function in vitro. Reduction of lysosomal enzyme release and superoxide anion production

PubMed Central

1977-01-01

Cationic local anesthetics have been reported to influence cellular responses to surface stimuli by interfering with the function of microtubules and microfilaments. Since unimpaired microtubule and microfilament functions are required by human polymorphonuclear leukocytes in order to respond normally to surface stimulation, we have studied effects of the local anesthetic, tetracaine on the function and morphology of these cells in vitro. Tetracaine (0.25--1.0 mM) significantly reduced extracellular release of the lysosomal enzymes, beta-glucuronidase and lysozyme from polymorphonuclear leukocytes exposed to serum-treated zymosan (a particulate stimulus), zymosan- treated serum (a soluble stimulus), and to the surface-active lectin, concanavalin A. Tetracaine also significantly reduced superoixde anion production (superoxide dismutase-inhibitable cytochrome c reduction) by these cells. Tetrancaine was not cytotoxic and its effects could be reversed completely by washing cells once with buffer. Electron microscope examination of tetracaine-treated cells revealed marked alterations of surface membranes. Microtubules and microfilaments appeared normal in "resting" polymorphonuclear leukocytes, but the increase in microtubules normally observed in stimulated cells was not seen after tetracaine treatment. These results suggest that tetracaine interferes with those interactions between immune reactants and the polymorphonuclear leukocyte cell surface which provoke exocytosis and increased oxidative metabolism. PMID:195003

Possible carcinogenic potential of dimethyl dimethoxy biphenyl dicarboxylate in experimental animals

PubMed Central

Botros, Sanaa Sabet; El-Lakkany, Naglaa Mohamed; Hammam, Olfat Ali; Sabra, Abdel-Naser Abdel-Aal; Taha, Alaa Awad

2016-01-01

Dimethyl dimethoxy biphenyl dicarboxylate (DDB) has been extensively used in the treatment of liver diseases accounting for 1–6% of the global disease burden. Cell replication, DNA synthesis, and proliferation, providing significant information about behavior of cells were examined in mice exposed to subchronic administration with DDB. Conventional liver functions specifically gamma-glutamyltransferase (γ-GT), a marker expressing liver canceration was also investigated. Normal mice were allocated into two groups each of 10 mice. The 1st and 2nd groups were treated with DDB in a dose of 50 mg/kg/day, 5 days/week for 1 month and 3 months, respectively. Comparable groups of normal mice were left without treatment as controls. Compared to normal control group, animals receiving DDB for 3 months showed marked elevations of both alanine aminotransferase and γ-GT, significant inhibition in cytochrome P450, a significant increase in the mean ploidy and 4C with moderate to marked increase in S-phase populations and the number of proliferating cell nuclear antigen-positive cells. In conclusion, this is the first report on the potential relationship between the subchronic administration of DDB and the increase in the hepatocyte proliferation, cell replication and DNA synthesis that may raise an alarm regarding possible DDB insult on the biological behavior of cells. PMID:27144153

Targeting of free fatty acid receptor 1 in EOC: A novel strategy to restrict the adipocyte-EOC dependence.

PubMed

Munkarah, Adnan; Mert, Ismail; Chhina, Jasdeep; Hamid, Suhail; Poisson, Laila; Hensley-Alford, Sharon; Giri, Shailendra; Rattan, Ramandeep

2016-04-01

Adipocyte derived free fatty acids (FFA) promote epithelial ovarian cancer (EOC) by acting as a fuel source to support the energy requirement of the cancer cells. FFA may also exert biological effects through signaling pathways. Recently, a family of FFA activated G-protein coupled receptors (FFAR/GPCRs) was identified. Our objective was to investigate the role of FFAR/GPCRs in EOC and assess their potential as therapeutic targets. The mRNA (RT-PCR) expression of FFAR/GPCR family members (FFAR1/GPR40; FFAR2/GPR43, FFAR3/GPR41, FFAR4/GPR120 and GPR84) was examined in: (1) a syngeneic mouse model of EOC fed high energy diet (60% fat) or regular diet (30% fat), (2) EOC cell lines exposed to free fatty acids and (3) specimens from 13 histologically normal ovaries and 28 high grade ovarian serous carcinomas. The GPR 40 antagonist, GW1100, was used to inhibit FFAR1/GPR40 and cell survival was assayed by MTT in various cell lines. High Grade Serous carcinoma specimens expressed significantly increased GPR40 compared to normal ovaries (p=0.0020). Higher expression was noted in advanced stage disease. ID8 ovarian tumors from mice fed with high fat diet also showed higher GPR40 expression. Exposing EOC cells to FFAs, increased GPR40 expression. Treatment of EOC cell lines with GW100 resulted in growth inhibition and was associated with an alteration in their energy metabolism. FFA-induced cancer cell growth may be partly mediated through FFAR1/GPR40. Targeting of FFAR1/GPR40 may be an attractive treatment strategy in EOC, and possibly offers a targeted treatment for a subset of EOC patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Single- and double-walled carbon nanotubes enhance atherosclerogenesis by promoting monocyte adhesion to endothelial cells and endothelial progenitor cell dysfunction.

PubMed

Suzuki, Yuka; Tada-Oikawa, Saeko; Hayashi, Yasuhiko; Izuoka, Kiyora; Kataoka, Misa; Ichikawa, Shunsuke; Wu, Wenting; Zong, Cai; Ichihara, Gaku; Ichihara, Sahoko

2016-10-13

The use of carbon nanotubes has increased lately. However, the cardiovascular effect of exposure to carbon nanotubes remains elusive. The present study investigated the effects of pulmonary exposure to single-walled carbon nanotubes (SWCNTs) and double-walled carbon nanotubes (DWCNTs) on atherosclerogenesis using normal human aortic endothelial cells (HAECs) and apolipoprotein E-deficient (ApoE -/- ) mice, a model of human atherosclerosis. HAECs were cultured and exposed to SWCNTs or DWCNTs for 16 h. ApoE -/- mice were exposed to SWCNTs or DWCNTs (10 or 40 μg/mouse) once every other week for 10 weeks by pharyngeal aspiration. Exposure to CNTs increased the expression level of adhesion molecule (ICAM-1) and enhanced THP-1 monocyte adhesion to HAECs. ApoE -/- mice exposed to CNTs showed increased plaque area in the aorta by oil red O staining and up-regulation of ICAM-1 expression in the aorta, compared with vehicle-treated ApoE -/- mice. Endothelial progenitor cells (EPCs) are mobilized from the bone marrow into the circulation and subsequently migrate to the site of endothelial damage and repair. Exposure of ApoE -/- mice to high-dose SWCNTs or DWCNTs reduced the colony-forming units of EPCs in the bone marrow and diminished their migration function. The results suggested that SWCNTs and DWCNTs enhanced atherosclerogenesis by promoting monocyte adhesion to endothelial cells and inducing EPC dysfunction.

Desquamation takes center stage at the origin of proliferative inflammatory atrophy, epithelial-mesenchymal transition, and stromal growth in benign prostate hyperplasia.

PubMed

Ferrucci, Danilo; Biancardi, Manoel F; Nishan, Umar; Rosa-Ribeiro, Rafaela; Carvalho, Hernandes F

2017-11-01

In this commentary, we propose a relationship between desquamation, initially described as the collective detachment and deletion of epithelial cell in the prostate gland after castration, and proliferative inflammatory atrophy (PIA) and stromal growth in benign prostate hyperplasia (BPH). First, in response to diverse stimuli, including inflammatory mediators, epithelial cells desquamate and leave a large surface of the luminal side of the basement membrane (BM) exposed. Basal cells are activated into intermediate-type cells, which change morphology to cover and remodel the exposed BM (simple atrophy) to a new physiological demand (such as in the hypoandrogen environment, simulated by surgical and/or chemical castration) and/or to support re-epithelialization (under normal androgen levels). In the presence of inflammation (that might be the cause of desquamation), the intermediate-type cells proliferate and characterize PIA. Second, in other circumstances, desquamation is an early step of epithelial-to-mesenchymal transition (EMT), which contributes to stromal growth, as suggested by some experimental models of BPH. The proposed associations correlate unexplored cell behaviors and reveal the remarkable plasticity of the prostate epithelium that might be at the origin of prostate diseases. © 2017 International Federation for Cell Biology.

Theobroma cacao increases cells viability and reduces IL-6 and sVCAM-1 level in endothelial cells induced by plasma from preeclamptic patients.

PubMed

Rahayu, Budi; Baktiyani, Siti Candra Windu; Nurdiana, Nurdiana

2016-01-01

This study aims to investigate whether an ethanolic extract of Theobroma cacao bean is able to increase cell viability and decrease IL-6 and sVCAM-1 in endothelial cells induced by plasma from preeclamptic patients. Endothelial cells were obtained from human umbilical vascular endothelial cells. At confluency, endothelial cells were divided into six groups, which included control (untreated), endothelial cells exposed to plasma from normal pregnancy, endothelial cells exposed to 2% plasma from preeclamptic patients (PP), endothelial cells exposed to PP in the presence of ethanolic extract of T. cacao (PP+TC) at the following three doses: 25, 50, and 100 ppm. The analysis was performed in silico using the Hex 8.0, LigPlus and LigandScout 3.1 software. Analysis on IL-6 and sVCAM-1 levels were done by enzyme linked immunosorbent assay (ELISA). We found that seven of them could bind to the protein NFκB (catechin, leucoanthocyanidin, niacin, phenylethylamine, theobromine, theophylline, and thiamin). This increase in IL-6 was significantly (P<0.05) attenuated by both the 50 and 100 ppm treatments of T. cacao extract. Plasma from PP significantly increased sVCAM-1 levels compared to untreated cells. This increase in sVCAM-1 was significantly attenuated by all doses of the extract. In conclusion, T. cacao extract prohibits the increase in IL-6 and sVCAM-1 in endothelial cells induced by plasma from preeclamptic patients. Therefore this may provide a herbal therapy for attenuating the endothelial dysfunction found in preeclampsia. Copyright © 2016 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

Biodistribution and photodynamic effects of polyvinylpyrrolidone-hypericin using multicellular spheroids composed of normal human urothelial and T24 transitional cell carcinoma cells.

PubMed

Vandepitte, Joachim; Roelants, Mieke; Van Cleynenbreugel, Ben; Hettinger, Klaudia; Lerut, Evelyne; Van Poppel, Hendrik; de Witte, Peter A M

2011-01-01

Polyvinylpyrrolidone (PVP)-hypericin is a potent photosensitizer that is used in the urological clinic to photodiagnose with high-sensitivity nonmuscle invasive bladder cancer (NMIBC). We examined the differential accumulation and therapeutic effects of PVP-hypericin using spheroids composed of a human urothelial cell carcinoma cell line (T24) and normal human urothelial (NHU) cells. The in vitro biodistribution was assessed using fluorescence image analysis of 5-μm cryostat sections of spheroids that were incubated with PVP-hypericin. The results show that PVP-hypericin accumulated to a much higher extent in T24 spheroids as compared to NHU spheroids, thereby reproducing the clinical situation. Subsequently, spheroids were exposed to different PDT regimes with a light dose ranging from 0.3 to 18 J∕cm2. When using low fluence rates, only minor differences in cell survival were seen between normal and malignant spheroids. High light fluence rates induced a substantial difference in cell survival between the two spheroid types, killing ∼80% of the cells present in the T24 spheroids. It was concluded that further in vivo experiments are required to fully evaluate the potential of PVP-hypericin as a phototherapeutic for NMIBC, focusing on the combination of the compound with methods that enhance the oxygenation of the urothelium.

Chromosome analysis from peripheral blood lymphocytes of workers after an acute exposure to benzene.

PubMed Central

Clare, M G; Yardley-Jones, A; Maclean, A C; Dean, B J

1984-01-01

A spillage of about 1200 gallons of benzene occurred during the loading of a ship, and 10 workers on a single shift were exposed to benzene. Shortly afterwards, an assay of the urine of these individuals showed that substantial amounts of phenol were being excreted. About three months after the incident samples of venous blood were taken from 10 individuals exposed to benzene and 11 men on a comparable shift who acted as controls. The lymphocytes were stimulated to divide in short term cultures. For each subject, 200 cells at metaphase were examined for chromosome damage using 48 h cultures, and sister chromatid exchanges (SCE) were analysed from about 30 cells in their second division, using 72 h cultures. The most frequent types of aberrations in all the individuals were chromatid gaps, with occasional breaks of chromatids and chromosomes. There were few exchanges within or between the arms of chromatids or chromosomes. More cells in the control than in the exposed group showed damage, an effect that was especially noticeable for chromatid gaps. All values, however, were considered to be within a normal range. There were slightly more SCE in some of the exposed individuals than in the controls and there was a trend towards a positive association between the frequency of SCE recorded for each individual and the maximum value for the excretion of phenol in the urine on the day after the incident. There is no evidence to indicate that benzene induced any type of lasting chromosome damage in the lymphocytes of the 10 exposed workers when cells were examined about three months after the incident. PMID:6722051

Shedding Light on the Role of UV Exposure in Melanoma | Center for Cancer Research

Cancer.gov

When a cell is exposed to UV radiation, the chemical makeup of its DNA is changed in a specific manner, resulting in a recognizable modification that can be measured by scientists. These changes are normally detected and fixed by cellular mechanisms for DNA repair. However, if the damage is extensive or if a cell has defective DNA repair machinery, permanent mutations can be produced with harmful consequences for the cell. If the mutation occurs within the gene for a protein that regulates cellular growth, the development of cancer is possible.

Effect of N-acetylcysteine administration on the expression and activities of antioxidant enzymes and the malondialdehyde level in the blood of lead-exposed workers.

PubMed

Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Aleksandra; Machnik, Grzegorz; Birkner, Ewa

2014-03-01

We investigated whether treatment with N-acetylcysteine (NAC) reduces oxidative stress intensity and restores the expression and activities of superoxide dismutase (Sod1, SOD), catalase (Cat, CAT) and glutathione peroxidase (Gpx1, GPx) in lead-exposed workers. The exposed population was divided randomly into two groups. Workers in the first group (reference group, n=49) were not administered any drugs, while workers in the second group (n=122) were treated with NAC at three doses for 12 weeks (200 mg, 400 mg, 800 mg/day). NAC administered orally to lead-exposed workers normalized antioxidant enzyme activities in blood cells. Oxidative stress intensity measured as malondialdehyde (MDA) levels in serum, leukocytes and erythrocytes significantly decreased after NAC administration. NAC may be an alternative therapy for chronic lead intoxication. Copyright © 2014 Elsevier B.V. All rights reserved.

Cytogenetic investigation of subjects professionally exposed to radiofrequency radiation.

PubMed

Maes, Annemarie; Van Gorp, Urbain; Verschaeve, Luc

2006-03-01

Nowadays, virtually everybody is exposed to radiofrequency radiation (RFR) from mobile phone base station antennas or other sources. At least according to some scientists, this exposure can have detrimental health effects. We investigated cytogenetic effects in peripheral blood lymphocytes from subjects who were professionally exposed to mobile phone electromagnetic fields in an attempt to demonstrate possible RFR-induced genetic effects. These subjects can be considered well suited for this purpose as their RFR exposure is 'normal' though rather high, and definitely higher than that of the 'general population'. The alkaline comet assay, sister chromatid exchange (SCE) and chromosome aberration tests revealed no evidence of RFR-induced genetic effects. Blood cells were also exposed to the well known chemical mutagen mitomycin C in order to investigate possible combined effects of RFR and the chemical. No cooperative action was found between the electromagnetic field exposure and the mutagen using either the comet assay or SCE test.

Titan Cells Confer Protection from Phagocytosis in Cryptococcus neoformans Infections

PubMed Central

Okagaki, Laura H.

2012-01-01

The human fungal pathogen Cryptococcus neoformans produces an enlarged “titan” cell morphology when exposed to the host pulmonary environment. Titan cells exhibit traits that promote survival in the host. Previous studies showed that titan cells are not phagocytosed and that increased titan cell production in the lungs results in reduced phagocytosis of cryptococcal cells by host immune cells. Here, the effect of titan cell production on host-pathogen interactions during early stages of pulmonary cryptococcosis was explored. The relationship between titan cell production and phagocytosis was found to be nonlinear; moderate increases in titan cell production resulted in profound decreases in phagocytosis, with significant differences occurring within the first 24 h of the infection. Not only were titan cells themselves protected from phagocytosis, but titan cell formation also conferred protection from phagocytosis to normal-size cryptococcal cells. Large particles introduced into the lungs were not phagocytosed, suggesting the large size of titan cells protects against phagocytosis. The presence of large particles was unable to protect smaller particles from phagocytosis, revealing that titan cell size alone is not sufficient to provide the observed cross-protection of normal-size cryptococcal cells. These data suggest that titan cells play a critical role in establishment of the pulmonary infection by promoting the survival of the entire population of cryptococcal cells. PMID:22544904

Titan cells confer protection from phagocytosis in Cryptococcus neoformans infections.

PubMed

Okagaki, Laura H; Nielsen, Kirsten

2012-06-01

The human fungal pathogen Cryptococcus neoformans produces an enlarged "titan" cell morphology when exposed to the host pulmonary environment. Titan cells exhibit traits that promote survival in the host. Previous studies showed that titan cells are not phagocytosed and that increased titan cell production in the lungs results in reduced phagocytosis of cryptococcal cells by host immune cells. Here, the effect of titan cell production on host-pathogen interactions during early stages of pulmonary cryptococcosis was explored. The relationship between titan cell production and phagocytosis was found to be nonlinear; moderate increases in titan cell production resulted in profound decreases in phagocytosis, with significant differences occurring within the first 24 h of the infection. Not only were titan cells themselves protected from phagocytosis, but titan cell formation also conferred protection from phagocytosis to normal-size cryptococcal cells. Large particles introduced into the lungs were not phagocytosed, suggesting the large size of titan cells protects against phagocytosis. The presence of large particles was unable to protect smaller particles from phagocytosis, revealing that titan cell size alone is not sufficient to provide the observed cross-protection of normal-size cryptococcal cells. These data suggest that titan cells play a critical role in establishment of the pulmonary infection by promoting the survival of the entire population of cryptococcal cells.

CO2 laser debridement of sulphur mustard (bis-2-chloroethyl sulphide) induced cutaneous lesions accelerates production of a normal epidermis with elimination of cytological atypia.

PubMed

Smith, K J; Skelton, H G; Martin, J L; Hurst, C G; Hackley, B E

1997-10-01

Sulphur mustard (bis-2-chloroethyl sulphide; HD) exposure acutely produces lesions that vary from mild erythema, to blister formation, to necrosis. When blisters occur, with or without necrosis, healing of the lesions is delayed. Weanling pigs exposed to a mild erythema-producing dose of HD and to a moderate erythema-producing dose that consistently gave microblister formation were treated with CO2 laser (Tru-Pulse) debridement at 6, 24 or 48 h after exposure. The histopathological features observed at 14 days after exposure in control skin and skin exposed to both HD doses were compared with the features observed in CO2 laser-debrided skin in non-exposed and HD-exposed skin sites. The overlying epidermis in the non-laser treated lesions was thin, with cytological atypia and squamoid changes within the basal cell layer, as well as scattered apoptotic/necrotic keratinocytes. An increased inflammatory infiltrate and necrobiotic changes in the dermis were seen at the higher HD dose. All laser-treated lesions appeared identical, with a thick, differentiated epidermis and a well-formed basal cell layer. There was minimal inflammatory infiltrate. In the papillary dermis there were increased stromal cells. Laser debridement of mild clinical lesions induced by HD produced a more functional epidermis by 14 days as well as clearing the epidermis of damaged keratinocytes.

An Apoptotic 'Eat Me' Signal: Phosphatidylserine Exposure.

PubMed

Segawa, Katsumori; Nagata, Shigekazu

2015-11-01

Apoptosis and the clearance of apoptotic cells are essential processes in animal development and homeostasis. For apoptotic cells to be cleared, they must display an 'eat me' signal, most likely phosphatidylserine (PtdSer) exposure, which prompts phagocytes to engulf the cells. PtdSer, which is recognized by several different systems, is normally confined to the cytoplasmic leaflet of the plasma membrane by a 'flippase'; apoptosis activates a 'scramblase' that quickly exposes PtdSer on the cell surface. The molecules that flip and scramble phospholipids at the plasma membrane have recently been identified. Here we discuss recent findings regarding the molecular mechanisms of apoptotic PtdSer exposure and the clearance of apoptotic cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Silver nanoparticle-induced degranulation observed with quantitative phase microscopy

NASA Astrophysics Data System (ADS)

Yang, Wenzhong; Lee, Seungrag; Lee, Jiyong; Bae, Yoonsung; Kim, Dugyoung

2010-07-01

Monitoring a degranulation process in a live mast cell is a quite important issue in immunology and pharmacology. Because the size of a granule is normally much smaller than the resolution limit of an optical microscope system, there is no direct real-time live cell imaging technique for observing degranulation processes except for fluorescence imaging techniques. In this research, we propose optical quantitative phase microscopy (QPM) as a new observation tool to study degranulation processes in a live mast cell without any fluorescence labeling. We measure the cell volumes and the cross sectional profiles (x-z plane) of an RBL-2H3 cell and a HeLa cell, before and after they are exposed to calcium ionophore A23187 and silver nanoparticles (AgNPs). We verify that the volume and the cross sectional line profile of the RBL-2H3 cell were changed significantly when it was exposed to A23187. When 50 μg/mL of AgNP is used instead of A23187, the measurements of cell volume and cross sectional profiles indicate that RBL-2H3 cells also follow degranulation processes. Degranulation processes for these cells are verified by monitoring the increase of intracellular calcium ([Ca2+]i) and histamine with fluorescent methods.

Reduced sperm counts in guppies (Poecilia reticulata) following exposure to low levels of tributyltin and bisphenol A.

PubMed Central

Haubruge, E; Petit, F; Gage, M J

2000-01-01

There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function. PMID:11413652

Reduced sperm counts in guppies (Poecilia reticulata) following exposure to low levels of tributyltin and bisphenol A.

PubMed

Haubruge, E; Petit, F; Gage, M J

2000-11-22

There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function.

In vivo imaging of tumor vascular endothelial cells

NASA Astrophysics Data System (ADS)

Zhao, Dawen; Stafford, Jason H.; Zhou, Heling; Thorpe, Philip E.

2013-02-01

Phosphatidylserine (PS), normally restricted to the inner leaflet of the plasma membrane, becomes exposed on the outer surface of viable (non-apoptotic) endothelial cells in tumor blood vessels, probably in response to oxidative stresses present in the tumor microenvironment. In the present study, we optically imaged exposed PS on tumor vasculature in vivo using PGN635, a novel human monoclonal antibody that targets PS. PGN635 F(ab')2 was labeled with the near infrared (NIR) dye, IRDye 800CW. Human glioma U87 cells or breast cancer MDA-MB-231 cells were implanted subcutaneously or orthotopically into nude mice. When the tumors reached ~5 mm in diameter, 800CW- PGN635 was injected via a tail vein and in vivo dynamic NIR imaging was performed. For U87 gliomas, NIR imaging allowed clear detection of tumors as early as 4 h later, which improved over time to give a maximal tumor/normal ratio (TNR = 2.9 +/- 0.5) 24 h later. Similar results were observed for orthotopic MDA-MB-231 breast tumors. Localization of 800CW-PGN635 to tumors was antigen specific since 800CW-Aurexis, a control probe of irrelevant specificity, did not localize to the tumors, and pre-administration of unlabeled PGN635 blocked the uptake of 800CW-PGN635. Fluorescence microscopy confirmed that 800CW-PGN635 was binding to PS-positive tumor vascular endothelium. Our studies suggest that tumor vasculature can be successfully imaged in vivo to provide sensitive tumor detection.

The protective effect of curcumin in Olfactory Ensheathing Cells exposed to hypoxia.

PubMed

Bonfanti, Roberta; Musumeci, Teresa; Russo, Cristina; Pellitteri, Rosalia

2017-02-05

Curcumin, a phytochemical component derived from the rhizomes of Curcuma longa, has shown a great variety of pharmacological activities, such as anti-inflammatory, anti-tumor, anti-depression and anti-oxidant activity. Therefore, in the last years it has been used as a therapeutic agent since it confers protection in different neurodegenerative diseases, cerebral ischemia and excitotoxicity. Olfactory Ensheathing Cells (OECs) are glial cells of the olfactory system. They are able to secrete several neurotrophic growth factors, promote axonal growth and support the remyelination of damaged axons. OEC transplantation has emerged as a possible experimental therapy to induce repair of spinal cord injury, even if the functional recovery is still limited. Since hypoxia is a secondary effect in spinal cord injury, this in vitro study investigates the protective effect of curcumin in OECs exposed to hypoxia. Primary OECs were obtained from neonatal rat olfactory bulbs and placed both in normal and hypoxic conditions. Furthermore, some cells were grown with basic Fibroblast Growth Factor (bFGF) and/or curcumin at different concentration and times. The results obtained through immunocytochemical procedures and MTT test show that curcumin stimulates cell viability in OECs grown in normal and hypoxic conditions. Furthermore, the synergistic effect of curcumin and bFGF is the most effective exerting protection on OECs. Since spinal cord injury is often accompanied by secondary insults, such as ischemia or hypoxia, our results suggest that curcumin in combination with bFGF might be considered a possible approach for restoration in injuries. Copyright © 2016 Elsevier B.V. All rights reserved.

Nanoparticulate zinc oxide as a coating material for orthopedic and dental implants.

PubMed

Memarzadeh, Kaveh; Sharili, Amir S; Huang, Jie; Rawlinson, Simon C F; Allaker, Robert P

2015-03-01

Orthopedic and dental implants are prone to infection. In this study, we describe a novel system using zinc oxide nanoparticles (nZnO) as a coating material to inhibit bacterial adhesion and promote osteoblast growth. Electrohydrodynamic atomisation (EHDA) was employed to deposit mixtures of nZnO and nanohydroxyapatite (nHA) onto the surface of glass substrates. Nano-coated substrates were exposed to Staphylococcus aureus suspended in buffered saline or bovine serum to determine antimicrobial activity. Our results indicate that 100% nZnO and 75% nZnO/25% nHA composite-coated substrates have significant antimicrobial activity. Furthermore, osteoblast function was explored by exposing cells to nZnO. UMR-106 cells exposed to nZnO supernatants showed minimal toxicity. Similarly, MG-63 cells cultured on nZnO substrates did not show release of TNF-α and IL-6 cytokines. These results were reinforced by both proliferation and differentiation studies which revealed that a substrate coated with exclusively nZnO is more efficient than composite surface coatings. Finally, electron and light microscopy, together with immunofluorescence staining, revealed that all cell types tested, including human mesenchymal cell (hMSC), were able to maintain normal cell morphology when adhered onto the surface of the nano-coated substrates. Collectively, these findings indicate that nZnO can, on its own, provide an optimal coating for future bone implants that are both antimicrobial and biocompatible. © 2014 Wiley Periodicals, Inc.

Preserved function of the plasma membrane calcium pump of red blood cells from diabetic subjects with high levels of glycated haemoglobin.

PubMed

Bookchin, Robert M; Etzion, Zipora; Lew, Virgilio L; Tiffert, Teresa

2009-03-01

The activity of the plasma membrane Ca(2+)-pump decreases steeply throughout the 120 days lifespan of normal human red blood cells. Experiments with isolated membrane preparations showed that glycation of a lysine residue near the catalytic site of the pump ATPase had a powerful inhibitory effect. This prompted the question of whether glycation is the mechanism of age-related decline in pump activity in vivo. It is important to investigate this mechanism because the Ca(2+) pump is a major regulator of Ca(2+) homeostasis in all cells. Its impaired activity in diabetic patients, continuously exposed to high glycation rates, may thus contribute to varied tissue pathology in this disease. We measured Ca(2+)-pump activity as a function of red cell age in red cells from diabetics continuously exposed to high glucose concentrations, as documented by their high mean levels of glycated haemoglobin. The distribution of Ca(2+)-pump activities was indistinguishable from that in non-diabetics, and the pattern of activity decline with cell age in the diabetics' red cells was identical to that observed in red cells from non-diabetics. These results indicate that in intact cells the Ca(2+) pump is protected from glycation-induced inactivation.

Chemical composition of PM10 and its in vitro toxicological impacts on lung cells during the Middle Eastern Dust (MED) storms in Ahvaz, Iran.

PubMed

Naimabadi, Abolfazl; Ghadiri, Ata; Idani, Esmaeil; Babaei, Ali Akbar; Alavi, Nadali; Shirmardi, Mohammad; Khodadadi, Ali; Marzouni, Mohammad Bagherian; Ankali, Kambiz Ahmadi; Rouhizadeh, Ahmad; Goudarzi, Gholamreza

2016-04-01

Reports on the effects of PM10 from dust storm on lung cells are limited. The main purpose of this study was to investigate the chemical composition and in vitro toxicological impacts of PM10 suspensions, its water-soluble fraction, and the solvent-extractable organics extracted from Middle Eastern Dust storms on the human lung epithelial cell (A549). Samples of dust storms and normal days (PM10 < 200 μg m(-3)) were collected from December 2012 until June 2013 in Ahvaz, the capital of Khuzestan Province in Iran. The chemical composition and cytotoxicity were analyzed by ICP- OES and Lactase Dehydrogenase (LDH) reduction assay, respectively. The results showed that PM10 suspensions, their water-soluble fraction and solvent-extractable organics from both dust storm and normal days caused a decrease in the cell viability and an increase in LDH in supernatant in a dose-response manner. Although samples of normal days showed higher cytotoxicity than those of dust storm at the highest treated dosage, T Test showed no significant difference in cytotoxicity between normal days and dust event days (P value > 0.05). These results led to the conclusions that dust storm PM10 as well as normal day PM10 could lead to cytotoxicity, and the organic compounds (PAHs) and the insoluble particle-core might be the main contributors to cytotoxicity. Our results showed that cytotoxicity and the risk of PM10 to human lung may be more severe during dust storm than normal days due to inhalation of a higher mass concentration of airborne particles. Further research on PM dangerous fractions and the most responsible components to make cytotoxicity in exposed cells is recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.

Omega-3 fatty acids, EPA and DHA induce apoptosis and enhance drug sensitivity in multiple myeloma cells but not in normal peripheral mononuclear cells.

PubMed

Abdi, J; Garssen, J; Faber, J; Redegeld, F A

2014-12-01

The n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to enhance the effect of chemotherapeutic drugs in clinical studies in cancer patients and to induce apoptotic tumor cell death in vitro. Until now, EPA and DHA have never been investigated in multiple myeloma (MM). Human myeloma cells (L363, OPM-1, OPM-2 and U266) and normal peripheral blood mononuclear cells were exposed to EPA and DHA, and effects on mitochondrial function and apoptosis, caspase-3 activation, gene expression and drug toxicity were measured. Exposure to EPA and DHA induced apoptosis and increased sensitivity to bortezomib in MM cells. Importantly, they did not affect viability of normal human peripheral mononuclear cells. Messenger RNA expression arrays showed that EPA and DHA modulated genes involved in multiple signaling pathways including nuclear factor (NF) κB, Notch, Hedgehog, oxidative stress and Wnt. EPA and DHA inhibited NFκB activity and induced apoptosis through mitochondrial perturbation and caspase-3 activation. Our study suggests that EPA and DHA induce selective cytotoxic effects in MM and increase sensitivity to bortezomib and calls for further exploration into a potential application of these n-3 polyunsaturated fatty acids in the therapy of MM. Copyright © 2014 Elsevier Inc. All rights reserved.

Cytotoxicity assessments of Portulaca oleracea and Petroselinum sativum seed extracts on human hepatocellular carcinoma cells (HepG2).

PubMed

Farshori, Nida Nayyar; Al-Sheddi, Ebtesam Saad; Al-Oqail, Mai Mohammad; Musarrat, Javed; Al-Khedhairy, Abdulaziz Ali; Siddiqui, Maqsood Ahmed

2014-01-01

The Pharmacological potential, such as antioxidant, anti-inflammatory, and antibacterial activities of Portulaca oleracea (PO) and Petroselinum sativum (PS) extracts are well known. However, the preventive properties against hepatocellular carcinoma cells have not been explored so far. Therefore, the present investigation was designed to study the anticancer activity of seed extracts of PO and PS on the human hepatocellular carcinoma cells (HepG2). The HepG2 cells were exposed with 5-500 μg/ml of PO and PS for 24 h. After the exposure, cell viability by 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assay, neutral red uptake (NRU) assay, and cellular morphology by phase contrast inverted microscope were studied. The results showed that PO and PS extracts significantly reduced the cell viability of HepG2 in a concentration dependent manner. The cell viability was recorded to be 67%, 31%, 21%, and 17% at 50, 100, 250, and 500 μg/ml of PO, respectively by MTT assay and 91%, 62%, 27%, and 18% at 50, 100, 250, and 500 μg/ml of PO, respectively by NRU assay. PS exposed HepG2 cells with 100 μg/ml and higher concentrations were also found to be cytotoxic. The decrease in the cell viability at 100, 250, and 500 μg/ml of PS was recorded as 70%, 33%, and 15% by MTT assay and 63%, 29%, and 17%, respectively by NRU assay. Results also showed that PO and PS exposed cells reduced the normal morphology and adhesion capacity of HepG2 cells. HepG2 cells exposed with 50 μg/ml and higher concentrations of PO and PS lost their typical morphology, become smaller in size, and appeared in rounded bodies. Our results demonstrated preliminary screening of anticancer activity of Portulaca oleracea and Petroselinum sativum extracts against HepG2 cells, which can be further used for the development of a potential therapeutic anticancer agent.

Tibolone Preserves Mitochondrial Functionality and Cell Morphology in Astrocytic Cells Treated with Palmitic Acid.

PubMed

González-Giraldo, Yeimy; Garcia-Segura, Luis Miguel; Echeverria, Valentina; Barreto, George E

2018-05-01

Obesity has been associated with increased chronic neuroinflammation and augmented risk of neurodegeneration. This is worsened during the normal aging process when the levels of endogenous gonadal hormones are reduced. In this study, we have assessed the protective actions of tibolone, a synthetic steroid with estrogenic actions, on T98G human astrocytic cells exposed to palmitic acid, a saturated fatty acid used to mimic obesity in vitro. Tibolone improved cell survival, and preserved mitochondrial membrane potential in palmitic acid-treated astrocytic cells. Although we did not find significant actions of tibolone on free radical production, it modulated astrocytic morphology after treatment with palmitic acid. These data suggest that tibolone protects astrocytic cells by preserving both mitochondrial functionality and morphological complexity.

Radiofrequency (RF) effects on blood cells, cardiac, endocrine, and immunological functions.

PubMed

Black, David R; Heynick, Louis N

2003-01-01

Effects of radiofrequency electromagnetic fields (RFEMF) on the pituitary adrenocortical (ACTH), growth (GH), and thyroid (TSH) hormones have been extensively studied, and there is coherent research on reproductive hormones (FSH and LH). Those effects which have been identified are clearly caused by heating. The exposure thresholds for these effects in living mammals, including primates, have been established. There is limited evidence that indicates no interaction between RFEMF and the pineal gland or an effect on prolactin from the pituitary gland. Studies of RFEMF exposed blood cells have shown that changes or damage do not occur unless the cells are heated. White cells (leukocytes) are much more sensitive than red cells (erythrocytes) but white cell effects remain consistent with normal physiological responses to systemic temperature fluctuation. Lifetime studies of RFEMF exposed animals show no cumulative adverse effects in their endocrine, hematological, or immune systems. Cardiovascular tissue is not directly affected adversely in the absence of significant RFEMF heating or electric currents. The regulation of blood pressure is not influenced by ultra high frequency (UHF) RFEMF at levels commonly encountered in the use of mobile communication devices. Copyright 2003 Wiley-Liss, Inc.

Ciliatoxicity in human primary bronchiolar epithelial cells after repeated exposure at the air-liquid interface with native mainstream smoke of K3R4F cigarettes with and without charcoal filter.

PubMed

Aufderheide, Michaela; Scheffler, Stefanie; Ito, Shigeaki; Ishikawa, Shinkichi; Emura, Makito

2015-01-01

Mucociliary clearance is the primary physical mechanism to protect the human airways against harmful effects of inhaled particles. Environmental factors play a significant role in the impairment of this defense mechanism, whereas cigarette smoke is discussed to be one of the clinically most important causes. Impaired mucociliary clearance in smokers has been connected to changes in ciliated cells such as decreased numbers, altered structure and beat frequency. Clinical studies have shown that cilia length is reduced in healthy smokers and that long-term exposure to cigarette smoke leads to reduced numbers of ciliated cells in mice. We present an in vitro model of primary normal human bronchiolar epithelial (NHBE) cells with in vivo like morphology to study the influence of cigarette mainstream smoke on ciliated cells. We exposed mucociliary differentiated cultures repeatedly to non-toxic concentrations of mainstream cigarette smoke (4 cigarettes, 5 days/week, 8 repetitions in total) at the air-liquid interface. Charcoal filter tipped cigarettes were compared to those being equipped with standard cellulose acetate filters. Histopathological analyses of the exposed cultures showed a reduction of cilia bearing cells, shortening of existing cilia and finally disappearance of all cilia in cigarette smoke exposed cells. In cultures exposed to charcoal filtered cigarette smoke, little changes in cilia length were seen after four exposure repetitions, but those effects were reversed after a two day recovery period. Those differences indicate that volatile organic compounds, being removed by the charcoal filter tip, affect primary bronchiolar epithelial cells concerning their cilia formation and function comparable with the in vivo situation. In conclusion, our in vitro model presents a valuable tool to study air-borne ciliatoxic compounds. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

Phenotypic malignant changes and untargeted lipidomic analysis of long-term exposed prostate cancer cells to endocrine disruptors

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

Bedia, Carmen, E-mail: carmen.bedia@idaea.csic.es; Dalmau, Núria, E-mail: nuria.dalmau@idaea.csic.es; Jaumot, Joaquim, E-mail: joaquim.jaumot@idaea.csic.es

2015-07-15

Endocrine disruptors (EDs) are a class of environmental toxic molecules able to interfere with the normal hormone metabolism. Numerous studies involve EDs exposure to initiation and development of cancers, including prostate cancer. In this work, three different EDs (aldrin, aroclor 1254 and chlorpyrifos (CPF)) were investigated as potential inducers of a malignant phenotype in DU145 prostate cancer cells after a chronic exposure. Epithelial to mesenchymal transition (EMT) induction, proliferation, migration, colony formation and release of metalloproteinase 2 (MMP-2) were analyzed in 50-day exposed cells to the selected EDs. As a result, aldrin and CPF exposure led to an EMT inductionmore » (loss of 16% and 14% of E-cadherin levels, respectively, compared to the unexposed cells). Aroclor and CPF presented an increased migration (134% and 126%, respectively), colony formation (204% and 144%, respectively) and MMP-2 release (137% in both cases) compared to the unexposed cells. An untargeted lipidomic analysis was performed to decipher the lipids involved in the observed transformations. As general results, aldrin exposure showed a global decrease in phospholipids and sphingolipids, and aroclor and CPF showed an increase of certain phospholipids, glycosphingolipids as well as a remarkable increase of some cardiolipin species. Furthermore, the three exposures resulted in an increase of some triglyceride species. In conclusion, some significant changes in lipids were identified and thus we postulate that some lipid compounds and lipid metabolic pathways could be involved in the acquisition of the malignant phenotype in exposed prostate cancer cells to the selected EDs. - Highlights: • Aldrin, aroclor and chlorpyrifos induced an aggressive phenotype in DU145 cells. • An untargeted lipidomic analysis has been performed on chronic exposed cells. • Lipidomic results showed changes in specific lipid species under chronic exposure. • These lipids may have a role in the acquisition of a malignant phenotype.« less

Modulating glioma-mediated myeloid-derived suppressor cell development with sulforaphane

PubMed Central

Kumar, Ravi; de Mooij, Tristan; Peterson, Timothy E.; Kaptzan, Tatiana; Johnson, Aaron J.; Daniels, David J.; Parney, Ian F.

2017-01-01

Glioblastoma is the most common primary tumor of the brain and has few long-term survivors. The local and systemic immunosuppressive environment created by glioblastoma allows it to evade immunosurveillance. Myeloid-derived suppressor cells (MDSCs) are a critical component of this immunosuppression. Understanding mechanisms of MDSC formation and function are key to developing effective immunotherapies. In this study, we developed a novel model to reliably generate human MDSCs from healthy-donor CD14+ monocytes by culture in human glioma-conditioned media. Monocytic MDSC frequency was assessed by flow cytometry and confocal microscopy. The resulting MDSCs robustly inhibited T cell proliferation. A cytokine array identified multiple components of the GCM potentially contributing to MDSC generation, including Monocyte Chemoattractive Protein-1, interleukin-6, interleukin-8, and Macrophage Migration Inhibitory Factor (MIF). Of these, Macrophage Migration Inhibitory Factor is a particularly attractive therapeutic target as sulforaphane, a naturally occurring MIF inhibitor derived from broccoli sprouts, has excellent oral bioavailability. Sulforaphane inhibits the transformation of normal monocytes to MDSCs by glioma-conditioned media in vitro at pharmacologically relevant concentrations that are non-toxic to normal leukocytes. This is associated with a corresponding increase in mature dendritic cells. Interestingly, sulforaphane treatment had similar pro-inflammatory effects on normal monocytes in fresh media but specifically increased immature dendritic cells. Thus, we have used a simple in vitro model system to identify a novel contributor to glioblastoma immunosuppression for which a natural inhibitor exists that increases mature dendritic cell development at the expense of myeloid-derived suppressor cells when normal monocytes are exposed to glioma conditioned media. PMID:28666020

CD28 in thymocyte development and peripheral T cell activation in mice exposed to suspended particulate matter

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

Drela, Nadzieja; Zesko, Izabela; Jakubowska, Martyna

2006-09-01

The CD28:B7 signaling pathway is very important for the activity of mature peripheral T lymphocytes and thymocyte development. The proper development of thymocytes into mature single positive CD4{sup +}and CD8{sup +} T cells is crucial for almost all immune functions. In naturally occurring conditions, T cells maturation in the thymus is influenced by environmental agents. The expression of CD28 and the distribution of CD28{sup low/high} thymocytes have been examined at various stages of thymocyte development in BALB/c mice exposed to air-suspended particulate matter (ASM). Acute exposure to ASM resulted in the decrease of CD28 expression in the total thymocyte population.more » The increase of the percentage of CD28{sup low} and the decrease of CD28{sup high} thymocytes were observed, which may account for the acceleration of thymocyte development under the conditions of elevated risk resulting from the exposure of animals to environmental xenobiotics. ASM exposure resulted in the increase of the level of proliferation of lymph node T cells induced by anti-CD3 and anti-CD28 monoclonal antibodies activation despite normal expression of CD28 molecule. In contrast, the level of proliferation of spleen T cells was lowered or normal dependently of the concentration of stimuli used for activation. Results of these studies demonstrate that acute exposure of mice to ASM can result in the progression of two contrasting processes in the immune system: upregulation of thymocyte development, which contributes to the maintenance of peripheral T cell pool, and over-activation of lymph node lymphocytes, which may lead to uncontrolled immunostimulation.« less

Protein expression profile changes in human fibroblasts induced by low dose energetic protons

NASA Astrophysics Data System (ADS)

Zhang, Ye; Clement, Jade Q.; Gridley, Daila S.; Rodhe, Larry H.; Wu, Honglu

2009-12-01

Extrapolation of known radiation risks to the risks from low dose and low dose-rate exposures of human population, especially prolonged exposures of astronauts in the space radiation environment, relies in part on the mechanistic understanding of radiation induced biological consequences at the molecular level. While some genomic data at the mRNA level are available for cells or animals exposed to radiation, the data at the protein level are still lacking. Here, we studied protein expression profile changes using Panorama antibody microarray chips that contain antibodies to 224 proteins (or their phosphorylated forms) involved in cell signaling that included mostly apoptosis, cytoskeleton, cell cycle and signal transduction. Normal human fibroblasts were cultured until fully confluent and then exposed to 2 cGy of 150 MeV protons at high-dose rate. The proteins were isolated at 2 or 6 h after exposure and labeled with Cy3 for the irradiated cells and with Cy5 for the control samples before loading onto the protein microarray chips. The intensities of the protein spots were analyzed using ScanAlyze software and normalized by the summed fluorescence intensities and the housekeeping proteins. The results showed that low dose protons altered the expression of more than 10% of the proteins listed in the microarray analysis in various protein functional groups. Cell cycle (24%) related proteins were induced by protons and most of them were regulators of G1/S-transition phase. Comparison of the overall protein expression profiles, cell cycle related proteins, cytoskeleton and signal transduction protein groups showed significantly more changes induced by protons compared with other protein functional groups.

Somatic hypermutation and antigen-driven selection of B cells are altered in autoimmune diseases.

PubMed

Zuckerman, Neta S; Hazanov, Helena; Barak, Michal; Edelman, Hanna; Hess, Shira; Shcolnik, Hadas; Dunn-Walters, Deborah; Mehr, Ramit

2010-12-01

B cells have been found to play a critical role in the pathogenesis of several autoimmune (AI) diseases. A common feature amongst many AI diseases is the formation of ectopic germinal centers (GC) within the afflicted tissue or organ, in which activated B cells expand and undergo somatic hypermutation (SHM) and antigen-driven selection on their immunoglobulin variable region (IgV) genes. However, it is not yet clear whether these processes occurring in ectopic GCs are identical to those in normal GCs. The analysis of IgV mutations has aided in revealing many aspects concerning B cell expansion, mutation and selection in GC reactions. We have applied several mutation analysis methods, based on lineage tree construction, to a large set of data, containing IgV productive and non-productive heavy and light chain sequences from several different tissues, to examine three of the most profoundly studied AI diseases - Rheumatoid Arthritis (RA), Multiple Sclerosis (MS) and Sjögren's Syndrome (SS). We have found that RA and MS sequences exhibited normal mutation spectra and targeting motifs, but a stricter selection compared to normal controls, which was more apparent in RA. SS sequence analysis results deviated from normal controls in both mutation spectra and indications of selection, also showing differences between light and heavy chain IgV and between different tissues. The differences revealed between AI diseases and normal control mutation patterns may result from the different microenvironmental influences to which ectopic GCs are exposed, relative to those in normal secondary lymphoid tissues. Copyright © 2010 Elsevier Ltd. All rights reserved.

Further considerations on in vitro skeletal muscle cell death

PubMed Central

Battistelli, Michela; Salucci, Sara; Burattini, Sabrina; Falcieri, Elisabetta

2013-01-01

Summary The present review discusses the apoptotic behavior induced by chemical and physical triggers in C2C12 skeletal muscle cells, comparing myoblast to myotube sensitivity, and investigating it by means of morphological, biochemical and cytofluorimetric analyses. After all treatments, myotubes, differently from myoblasts, showed a poor sensitivity to cell death. Intriguingly, in cells exposed to staurosporine, etoposide and UVB radiation, apoptotic and normal nuclei within the same fibercould be revealed. The presence of nuclear-dependent “territorial” death domains in the syncytium could explain a delayed cell death of myotubes compared to mononucleated cells. Moreover, autophagic granules abundantly appeared in myotubes after each treatment. Autophagy could protect muscle cell integrity against chemical and physical stimuli, making C2C12 myotubes, more resistant to cell death induction. PMID:24596689

Exposure of articular chondrocytes to wear particles induces phagocytosis, differential inflammatory gene expression, and reduced proliferation.

PubMed

Kurdziel, Michael D; Salisbury, Meagan; Kaplan, Lige; Maerz, Tristan; Baker, Kevin C

2017-07-01

The production of wear debris particulate remains a concern due to its association with implant failure through complex biologic interactions. In the setting of unicompartmental knee arthroplasty (UKA), damage and wear of the components may introduce debris particulate into the adjacent, otherwise, healthy compartment. The purpose of this study was to investigate the in vitro effect of polymeric and metallic wear debris particles on cell proliferation, extracellular matrix regulation, and phagocytosis index of normal human articular chondrocytes (nHACs). In culture, nHACs were exposed to both cobalt-chromium-molybdenum (CoCrMo) and polymethyl-methacrylate (PMMA) wear debris particulate for 3 and 10 days. At 3 days, no significant difference in cell proliferation was found between control cells and cells exposed to both CoCrMo or PMMA particles. However, cell proliferation was significantly decreased for CoCrMo exposed nHACs at both 6 (P < 0.001) and 10 days (P < 0.001) and PMMA at 10 days (P < 0.001). Target gene expression displayed both a time- and material-dependent response to CoCrMo and PMMA particles. Significant differences in COL10A1, ACAN, VCAN, IL-1β, TNF-α, MMP3, ADAMTS1, CASP3, and CASP9 regulation were found between CoCrMo and PMMA exposed nHACs at day 3 with gene regulation returning to near baseline at 10 days. Results from our study indicate a role of wear debris induced cartilage degeneration after exposure to polymeric and metallic wear debris particulate, suggesting an additional pathway of cartilage breakdown, potentially manifesting in traditional clinical symptoms.

Arsenic Promotes NF-Kb-Mediated Fibroblast Dysfunction and Matrix Remodeling to Impair Muscle Stem Cell Function

PubMed Central

Zhang, Changqing; Ferrari, Ricardo; Beezhold, Kevin; Stearns-Reider, Kristen; D’Amore, Antonio; Haschak, Martin; Stolz, Donna; Robbins, Paul D.; Barchowsky, Aaron; Ambrosio, Fabrisia

2016-01-01

Arsenic is a global health hazard that impacts over 140 million individuals worldwide. Epidemiological studies reveal prominent muscle dysfunction and mobility declines following arsenic exposure; yet, mechanisms underlying such declines are unknown. The objective of this study was to test the novel hypothesis that arsenic drives a maladaptive fibroblast phenotype to promote pathogenic myomatrix remodeling and compromise the muscle stem (satellite) cell (MuSC) niche. Mice were exposed to environmentally relevant levels of arsenic in drinking water before receiving a local muscle injury. Arsenic-exposed muscles displayed pathogenic matrix remodeling, defective myofiber regeneration and impaired functional recovery, relative to controls. When naïve human MuSCs were seeded onto three-dimensional decellularized muscle constructs derived from arsenic-exposed muscles, cells displayed an increased fibrogenic conversion and decreased myogenicity, compared with cells seeded onto control constructs. Consistent with myomatrix alterations, fibroblasts isolated from arsenic-exposed muscle displayed sustained expression of matrix remodeling genes, the majority of which were mediated by NF-κB. Inhibition of NF-κB during arsenic exposure preserved normal myofiber structure and functional recovery after injury, suggesting that NF-κB signaling serves as an important mechanism of action for the deleterious effects of arsenic on tissue healing. Taken together, the results from this study implicate myomatrix biophysical and/or biochemical characteristics as culprits in arsenic-induced MuSC dysfunction and impaired muscle regeneration. It is anticipated that these findings may aid in the development of strategies to prevent or revert the effects of arsenic on tissue healing and, more broadly, provide insight into the influence of the native myomatrix on stem cell behavior. PMID:26537186

Investigation into the Role of Phosphatidylserine in Modifying the Susceptibility of Human Lymphocytes to Secretory Phospholipase A2 using Cells Deficient in the Expression of Scramblase

PubMed Central

Nelson, Jennifer; Francom, Lyndee L.; Anderson, Lynn; Damm, Kelly; Baker, Ryan; Chen, Joseph; Franklin, Sarah; Hamaker, Amy; Izidoro, Izadora; Moss, Eric; Orton, Mikayla; Stevens, Evan; Yeung, Celestine; Judd, Allan M.; Bell, John D.

2012-01-01

Summary Normal human lymphocytes resisted the hydrolytic action of secretory phospholipase A2 but became susceptible to the enzyme following treatment with a calcium ionophore, ionomycin. To test the hypothesis that this susceptibility requires exposure of the anionic lipid phosphatidylserine on the external face of the cell membrane, experiments were repeated with a human Burkitt’s lymphoma cell line (Raji cells). In contrast to normal lymphocytes or S49 mouse lymphoma cells, most of the Raji cells (83%) did not translocate phosphatidylserine to the cell surface upon treatment with ionomycin. Those few that did display exposed phosphatidylserine were hydrolyzed immediately upon addition of phospholipase A2. Interestingly, the remaining cells were also completely susceptible to the enzyme but were hydrolyzed at a slower rate and after a latency of about 100 s. In contradistinction to the defect in phosphatidylserine translocation, Raji cells did display other physical membrane changes upon ionomycin treatment that may be relevant to hydrolysis by phospholipase A2. These changes were detected by merocyanine 540 and trimethylammonium diphenylhexatriene fluorescence and were common among normal lymphocytes, S49 cells, and Raji cells. The levels of these latter effects corresponded well with the relative rates of hydrolysis among the three cell lines. These results suggested that while phosphatidylserine enhances the rate of cell membrane hydrolysis by secretory phospholipase A2, it is not an absolute requirement. Other physical properties such as membrane order contribute to the level of membrane susceptibility to the enzyme independent of phosphatidylserine. PMID:22266334

Reprogramming to developmental plasticity in cancer stem cells.

PubMed

O'Brien-Ball, Caitlin; Biddle, Adrian

2017-10-15

During development and throughout adult life, sub-populations of cells exist that exhibit phenotypic plasticity - the ability to differentiate into multiple lineages. This behaviour is important in embryogenesis, is exhibited in a more limited context by adult stem cells, and can be re-activated in cancer cells to drive important processes underlying tumour progression. A well-studied mechanism of phenotypic plasticity is the epithelial-to-mesenchymal transition (EMT), a process which has been observed in both normal and cancerous cells. The epigenetic and metabolic modifications necessary to facilitate phenotypic plasticity are first seen in development and can be re-activated both in normal regeneration and in cancer. In cancer, the re-activation of these mechanisms enables tumour cells to acquire a cancer stem cell (CSC) phenotype with enhanced ability to survive in hostile environments, resist therapeutic interventions, and undergo metastasis. However, recent research has suggested that plasticity may also expose weaknesses in cancer cells that could be exploited for future therapeutic development. More research is needed to identify developmental mechanisms that are active in cancer, so that these may be targeted to reduce tumour growth and metastasis and overcome therapeutic resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

An ultra-sensitive biophysical risk assessment of light effect on skin cells.

PubMed

Bennet, Devasier; Viswanath, Buddolla; Kim, Sanghyo; An, Jeong Ho

2017-07-18

The aim of this study was to analyze photo-dynamic and photo-pathology changes of different color light radiations on human adult skin cells. We used a real-time biophysical and biomechanics monitoring system for light-induced cellular changes in an in vitro model to find mechanisms of the initial and continuous degenerative process. Cells were exposed to intermittent, mild and intense (1-180 min) light with On/Off cycles, using blue, green, red and white light. Cellular ultra-structural changes, damages, and ECM impair function were evaluated by up/down-regulation of biophysical, biomechanical and biochemical properties. All cells exposed to different color light radiation showed significant changes in a time-dependent manner. Particularly, cell growth, stiffness, roughness, cytoskeletal integrity and ECM proteins of the human dermal fibroblasts-adult (HDF-a) cells showed highest alteration, followed by human epidermal keratinocytes-adult (HEK-a) cells and human epidermal melanocytes-adult (HEM-a) cells. Such changes might impede the normal cellular functions. Overall, the obtained results identify a new insight that may contribute to premature aging, and causes it to look aged in younger people. Moreover, these results advance our understanding of the different color light-induced degenerative process and help the development of new therapeutic strategies.

Molecular Modulation of Inhibitors of Apoptosis as a Novel Approach for Radiosensitization of Human Prostate Cancer

DTIC Science & Technology

2006-11-01

6 well plate at the concentration of 2X105/ml, then exposed by SH130 (10 uM) with or without the pan-caspase inhibitor zVAD (2.5 uM) ( Biovision ...treated with SH- 130 and radiation. DU-145 cell were treated as described in Figure 7. Cells were lysed by the lysis buffer ( Biovision ) as indicated...Total extracted proteins were determined and normalized, and then reacted with fluorogenic substrates ( Biovision , DEVD-AFC and LEHD- AFC for Caspase

Self-Renewal and Differentiation Capacity of Urine-Derived Stem Cells after Urine Preservation for 24 Hours

PubMed Central

Shi, Yingai; Bharadwaj, Shantaram; Leng, Xiaoyan; Zhou, Xiaobo; Liu, Hong; Atala, Anthony; Zhang, Yuanyuan

2013-01-01

Despite successful approaches to preserve organs, tissues, and isolated cells, the maintenance of stem cell viability and function in body fluids during storage for cell distribution and transportation remains unexplored. The aim of this study was to characterize urine-derived stem cells (USCs) after optimal preservation of urine specimens for up to 24 hours. A total of 415 urine specimens were collected from 12 healthy men (age range 20–54 years old). About 6×104 cells shed off from the urinary tract system in 24 hours. At least 100 USC clones were obtained from the stored urine specimens after 24 hours and maintained similar biological features to fresh USCs. The stored USCs had a “rice grain” shape in primary culture, and expressed mesenchymal stem cell surface markers, high telomerase activity, and normal karyotypes. Importantly, the preserved cells retained bipotent differentiation capacity. Differentiated USCs expressed myogenic specific proteins and contractile function when exposed to myogenic differentiation medium, and they expressed urothelial cell-specific markers and barrier function when exposed to urothelial differentiation medium. These data demonstrated that up to 75% of fresh USCs can be safely persevered in urine for 24 hours and that these cells stored in urine retain their original stem cell properties, indicating that preserved USCs could be available for potential use in cell-based therapy or clinical diagnosis. PMID:23349776

Involvement of epigenetics and EMT related miRNA in arsenic induced neoplastic transformation and their potential clinical use

PubMed Central

Michailidi, Christina; Hayashi, Masamichi; Datta, Sayantan; Sen, Tanusree; Zenner, Kaitlyn; Oladeru, Oluwadamilola; Brait, Mariana; Izumchenko, Evgeny; Baras, Alexander; VandenBussche, Christopher; Argos, Maria; Bivalacqua, Trinity J; Ahsan, Habibul; Hahn, Noah M.; Netto, George J.; Sidransky, David; Hoque, Mohammad O.

2015-01-01

Exposure to toxicants leads to cumulative molecular changes that overtime increase a subject’s risk of developing urothelial carcinoma (UC). To assess the impact of arsenic exposure at a time progressive manner, we developed and characterized a cell culture model and tested a panel of miRNAs in urine samples from arsenic exposed subjects, UC patients and controls. To prepare an in vitro model, we chronically exposed an immortalized normal human bladder cell line (HUC1) to arsenic. Growth of the HUC1 cells was increased in a time dependent manner after arsenic treatment and cellular morphology was changed. In soft agar assay, colonies were observed only in arsenic treated cells and the number of colonies gradually increased with longer periods of treatment. Similarly, invaded cells in invasion assay were observed only in arsenic treated cells. Withdrawal of arsenic treatment for 2.5 months did not reverse the tumorigenic properties of arsenic treated cells. Western blot analysis demonstrated decreased PTEN and increased AKT and mTOR in arsenic treated HUC1 cells. Levels of miR-200a, miR-200b, and miR-200c were down-regulated in arsenic exposed HUC1 cells by quantitative RT-PCR. Furthermore, in human urine, miR-200c and miR-205 were inversely associated with arsenic exposure (P=0.005 and 0.009, respectively). Expression of miR-205 discriminated cancer cases from controls with high sensitivity and specificity (AUC=0.845). Our study suggests that exposure to arsenic rapidly induces a multifaceted dedifferentiation program and miR-205 has potential to be used as a marker of arsenic exposure as well as a maker of early UC detection. PMID:25586904

Biomonitoring of Toxic Effects of Pesticides in Occupationally Exposed Individuals.

PubMed

Arshad, Muhammad; Siddiqa, Maryam; Rashid, Saddaf; Hashmi, Imran; Awan, Muhammad Ali; Ali, Muhammad Arif

2016-06-01

Workers in pesticide manufacturing industries are constantly exposed to pesticides. Genetic biomonitoring provides an early identification of potential cancer and genetic diseases in exposed populations. The objectives of this biomonitoring study were to assess DNA damage through comet assay in blood samples collected from industry workers and compare these results with those of classical analytical techniques used for complete blood count analysis. Samples from controls (n = 20) and exposed workers (n = 38) from an industrial area in Multan, Pakistan, were subjected to various tests. Malathion residues in blood samples were measured by gas chromatography. The exposed workers who were employed in the pesticide manufacturing industry for a longer period (i.e., 13-25 years) had significantly higher DNA tail length (7.04 μm) than the controls (0.94 μm). Workers in the exposed group also had higher white blood cell and red blood cell counts, and lower levels of mean corpuscular hemoglobin (MCH), MCH concentration, and mean corpuscular volume in comparison with normal levels for these parameters. Malathion was not detected in the control group. However, in the exposed group, 72% of whole blood samples had malathion with a mean value of 0.14 mg/L (range 0.01-0.31 mg/L). We found a strong correlation (R (2) = 0.91) between DNA damage in terms of tail length and malathion concentration in blood. Intensive efforts and trainings are thus required to build awareness about safety practices and to change industrial workers' attitude to prevent harmful environmental and anthropogenic effects.

Relationship of inflammatory cell cytokines to disease severity in individuals with occupational inorganic dust exposure.

PubMed

Rom, W N

1991-01-01

The pneumoconioses due to chronic occupational exposure to asbestos, coal, or silica are characterized by an alveolar macrophage-dominated alveolitis with exaggerated spontaneous release of mediators: oxidants, chemotaxins for neutrophils, and fibroblast growth factors. Bronchoalveolar lavage was performed on 66 non-smoking inorganic dust-exposed individuals with a chest x-ray greater than or equal to 1/0 stratified by presence or absence of restrictive respiratory impairment, and 28 unexposed non-smoking controls. Both dust-exposed groups stratified by presence or not of impairment had increased numbers of total cells recovered by lavage compared to normals, and those with respiratory impairment (n = 40) had a significant increase in percent and number of neutrophils recovered. Similarly, only those with respiratory impairment had macrophages that spontaneously released significant amounts of the oxidants superoxide anion and hydrogen peroxide. There was a significant trend for the release of fibronectin by macrophages from controls to dust-exposed without impairment to those with impairment. Both dust-exposed groups also had increased release of alveolar macrophage-derived progression growth factor, but this was significantly less than macrophages from patients with idiopathic pulmonary fibrosis. Since occupational exposure was virtually identical in inorganic dust-exposed individuals with versus without respiratory impairment, the quantitative differences in the release of macrophage mediators may be due to factors in host susceptibility.

Biliary epithelium and liver B cells exposed to bacteria activate intrahepatic MAIT cells through MR1

PubMed Central

Jeffery, Hannah C.; van Wilgenburg, Bonnie; Kurioka, Ayako; Parekh, Krishan; Stirling, Kathryn; Roberts, Sheree; Dutton, Emma E.; Hunter, Stuart; Geh, Daniel; Braitch, Manjit K.; Rajanayagam, Jeremy; Iqbal, Tariq; Pinkney, Thomas; Brown, Rachel; Withers, David R.; Adams, David H.; Klenerman, Paul; Oo, Ye H.

2016-01-01

Background & Aims Mucosal-Associated Invariant T (MAIT) cells are innate-like T cells characterised by the invariant TCR-chain, Vα7.2-Jα33, and are restricted by MR1, which presents bacterial vitamin B metabolites. They are important for antibacterial immunity at mucosal sites; however, detailed characteristics of liver-infiltrating MAIT (LI-MAIT) and their role in biliary immune surveillance remain unexplored. Methods The phenotype and intrahepatic localisation of human LI-MAIT cells was examined in diseased and normal livers. MAIT cell activation in response to E. coli-exposed macrophages, biliary epithelial cells (BEC) and liver B cells was assessed with/without anti-MR1. Results Intrahepatic MAIT cells predominantly localised to bile ducts in the portal tracts. Consistent with this distribution, they expressed biliary tropic chemokine receptors CCR6, CXCR6, and integrin αEβ7. LI-MAIT cells were also present in the hepatic sinusoids and possessed tissue-homing chemokine receptor CXCR3 and integrins LFA-1 and VLA-4, suggesting their recruitment via hepatic sinusoids. LI-MAIT cells were enriched in the parenchyma of acute liver failure livers compared to chronic diseased livers. LI-MAIT cells had an activated, effector memory phenotype, expressed α4β7 and receptors for IL-12, IL-18, and IL-23. Importantly, in response to E. coli-exposed macrophages, liver B cells and BEC, MAIT cells upregulated IFN-γ and CD40 Ligand and degranulated in an MR1-dependent, cytokine-independent manner. In addition, diseased liver MAIT cells expressed T-bet and RORγt and the cytokines IFN-γ, TNF-α, and IL-17. Conclusions Our findings provide the first evidence of an immune surveillance effector response for MAIT cells towards BEC in human liver; thus they could be manipulated for treatment of biliary disease in the future. PMID:26743076

Biliary epithelium and liver B cells exposed to bacteria activate intrahepatic MAIT cells through MR1.

PubMed

Jeffery, Hannah C; van Wilgenburg, Bonnie; Kurioka, Ayako; Parekh, Krishan; Stirling, Kathryn; Roberts, Sheree; Dutton, Emma E; Hunter, Stuart; Geh, Daniel; Braitch, Manjit K; Rajanayagam, Jeremy; Iqbal, Tariq; Pinkney, Thomas; Brown, Rachel; Withers, David R; Adams, David H; Klenerman, Paul; Oo, Ye H

2016-05-01

Mucosal-Associated Invariant T (MAIT) cells are innate-like T cells characterised by the invariant TCR-chain, Vα7.2-Jα33, and are restricted by MR1, which presents bacterial vitamin B metabolites. They are important for antibacterial immunity at mucosal sites; however, detailed characteristics of liver-infiltrating MAIT (LI-MAIT) and their role in biliary immune surveillance remain unexplored. The phenotype and intrahepatic localisation of human LI-MAIT cells was examined in diseased and normal livers. MAIT cell activation in response to E. coli-exposed macrophages, biliary epithelial cells (BEC) and liver B cells was assessed with/without anti-MR1. Intrahepatic MAIT cells predominantly localised to bile ducts in the portal tracts. Consistent with this distribution, they expressed biliary tropic chemokine receptors CCR6, CXCR6, and integrin αEβ7. LI-MAIT cells were also present in the hepatic sinusoids and possessed tissue-homing chemokine receptor CXCR3 and integrins LFA-1 and VLA-4, suggesting their recruitment via hepatic sinusoids. LI-MAIT cells were enriched in the parenchyma of acute liver failure livers compared to chronic diseased livers. LI-MAIT cells had an activated, effector memory phenotype, expressed α4β7 and receptors for IL-12, IL-18, and IL-23. Importantly, in response to E. coli-exposed macrophages, liver B cells and BEC, MAIT cells upregulated IFN-γ and CD40 Ligand and degranulated in an MR1-dependent, cytokine-independent manner. In addition, diseased liver MAIT cells expressed T-bet and RORγt and the cytokines IFN-γ, TNF-α, and IL-17. Our findings provide the first evidence of an immune surveillance effector response for MAIT cells towards BEC in human liver; thus they could be manipulated for treatment of biliary disease in the future. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Differential regulation of glutathione peroxidase by selenomethionine and hyperoxia in endothelial cells.

PubMed Central

Jornot, L; Junod, A F

1995-01-01

We have studied the effect of selenomethionine (SeMet) and hyperoxia on the expression of glutathione peroxidase (GP) in human umbilical vein endothelial cells. Incubation of HUVEC with 1 x 10(-6) M SeMet for 24 h and 48 h caused a 65% and 86% increase in GP activity respectively. The same treatment did not result in significant changes in GP gene transcription and mRNA levels. Pactamycin, a specific inhibitor of the initiation step of translation, prevented the rise in GP activity induced by SeMet and caused an increase in GP mRNA in both cells grown in normal and SeMet-supplemented medium. Interestingly, SeMet supplementation stimulated the recruitment of GP mRNA from an untranslatable pool on to polyribosomes, so that the concentration of GP mRNA in polyribosomal translatable pools was 50% higher in cells grown in SeMet-supplemented medium than in cells grown in normal medium. On the other hand, cells exposed to 95% O2 for 3 days in normal medium showed a 60%, 394% and 81% increase in GP gene transcription rate, mRNA levels and activity respectively. Hyperoxia also stabilized GP mRNA. Hyperoxic cells grown in SeMet-supplemented medium did not show any change in GP gene transcription and mRNA levels, but expressed an 81% and 100% increase in GP activity and amount of GP mRNA associated with polyribosomes respectively, when compared with hyperoxic cells maintained in normal medium. Thus, GP appeared to be regulated post-transcriptionally, most probably co-translationally, in response to selenium availability, and transcriptionally and post-transcriptionally in response to oxygen. Images Figure 1 Figure 2 Figure 4 Figure 7 Figure 8 PMID:7887914

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

Yamamoto, Tetsuya; Digumarthi, Hari; Aranbayeva, Zina

The green tea polyphenol epigallocatechin-3-gallate (EGCG) regulates gene expression differentially in tumor and normal cells. In normal human primary epidermal keratinocytes (NHEK), one of the key mediators of EGCG action is p57/KIP2, a cyclin-dependent kinase (CDK) inhibitor. EGCG potently induces p57 in NHEK, but not in epithelial cancer cells. In humans, reduced expression of p57 often is associated with advanced tumors, and tumor cells with inactivated p57 undergo apoptosis when exposed to EGCG. The mechanism of p57 induction by EGCG is not well understood. Here, we show that in NHEK, EGCG-induces p57 via the p38 mitogen-activated protein kinase (MAPK) signalingmore » pathway. In p57-negative tumor cells, JNK signaling mediates EGCG-induced apoptosis, and exogenous expression of p57 suppresses EGCG-induced apoptosis via inhibition of c-Jun N-terminal kinase (JNK). We also found that restoration of p57 expression in tumor cells significantly reduced tumorigenicity in athymic mice. These results suggest that p57 expression may be an useful indicator for the clinical course of cancers, and could be potentially useful as a target for cancer therapies.« less

Blue-light filtering alters angiogenic signaling in human retinal pigmented epithelial cells culture model.

PubMed

Vila, Natalia; Siblini, Aya; Esposito, Evangelina; Bravo-Filho, Vasco; Zoroquiain, Pablo; Aldrees, Sultan; Logan, Patrick; Arias, Lluis; Burnier, Miguel N

2017-11-02

Light exposure and more specifically the spectrum of blue light contribute to the oxidative stress in Age-related macular degeneration (AMD). The purpose of the study was to establish whether blue light filtering could modify proangiogenic signaling produced by retinal pigmented epithelial (RPE) cells under different conditions simulating risk factors for AMD. Three experiments were carried out in order to expose ARPE-19 cells to white light for 48 h with and without blue light-blocking filters (BLF) in different conditions. In each experiment one group was exposed to light with no BLF protection, a second group was exposed to light with BLF protection, and a control group was not exposed to light. The ARPE-19 cells used in each experiment prior to light exposure were cultured for 24 h as follows: Experiment 1) Normoxia, Experiment 2) Hypoxia, and Experiment 3) Lutein supplemented media in normoxia. The media of all groups was harvested after light exposure for sandwich ELISA-based assays to quantify 10 pro-angiogenic cytokines. A significant decrease in angiogenin secretion levels and a significant increase in bFGF were observed following light exposure, compared to dark conditions, in both normoxia and hypoxia conditions. With the addition of a blue light-blocking filter in normoxia, a significant increase in angiogenin levels was observed. Although statistical significance was not achieved, blue light filters reduce light-induced secretion of bFGF and VEGF to near normal levels. This trend is also observed when ARPE-19 cells are grown under hypoxic conditions and when pre-treated with lutein prior to exposure to experimental conditions. Following light exposure, there is a decrease in angiogenin secretion by ARPE-19 cells, which was abrogated with a blue light - blocking filter. Our findings support the position that blue light filtering affects the secretion of angiogenic factors by retinal pigmented epithelial cells under normoxic, hypoxic, and lutein-pretreated conditions in a similar manner.

Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

NASA Astrophysics Data System (ADS)

Xu, Bo; Chen, Minjian; Yao, Mengmeng; Ji, Xiaoli; Mao, Zhilei; Tang, Wei; Qiao, Shanlei; Schick, Suzaynn F.; Mao, Jian-Hua; Hang, Bo; Xia, Yankai

2015-10-01

Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cell cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.

Immunological evaluation of four arc welders exposed to fumes from ignited polyurethane (isocyanate) foam: antibodies and immune profiles

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

Broughton, A.; Thrasher, J.D.; Gard, Z.

1988-01-01

Four arc welders having a flu-like illness with multiple health complaints following an exposure to high concentrations of isocyanate fumes from ignited polyurethane foam underwent immunological tests as follows: ELISA antibody assays, activated lymphocyte profiles, and lymphocyte blastogenesis. ELISA procedures revealed the presence of antibodies to hexamethylene diisocyanate (HDI) and formaldehyde (F) conjugated to human serum albumin (HDI-SA and F-SA). The results from the activated lymphocyte profiles showed deviations from the norm as follows: three welders had elevated helper/suppressor (H/S) ratios; all four had elevated percentages of Tal positive cells; two had decreases in B cells; and one had lowmore » total white cell and lymphocyte counts. In contrast, the percentage and absolute numbers of ILS receptor cells were normal in the four subjects. T cell blastogenesis to PHA, Con A and PWM resulted in the following: T-cells from one subject responded normally; in another, a high response (212% of controls) to PHA occurred with normal mitogenesis to Con A and PWM. In the remaining two welders, the T cells responded abnormally low (50 to 75% of controls) to the three mitogens. In conclusion, the existence of IgG antibodies to HDI-SA and F-SA, the altered activated immune profiles, the elevated Tal cells, and the abnormal blastogenesis are interpreted as being linked with the episode of HDI and F exposure and the subsequent flu-like illness of the four welders.« less

Autophagy levels are elevated in Barrett’s esophagus and promote cell survival from acid and oxidative stress

PubMed Central

Kong, Jianping; Whelan, Kelly A.; Laczkó, Dorottya; Dang, Brendan; Monroig, Angeliz Caro; Soroush, Ali; Falcone, John; Amaravadi, Ravi K.; Rustgi, Anil K.; Ginsberg, Gregory G; Falk, Gary W; Nakagawa, Hiroshi; Lynch, John P.

2015-01-01

Autophagy is a highly conserved mechanism that is activated during cellular stress. We hypothesized that autophagy may be induced by acid reflux, which causes injury and inflammation, and therefore contributes to the pathogenesis of Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC). Currently, the role of autophagy in BE and EAC is poorly studied. We quantitatively define autophagy levels in human BE cell lines, a transgenic mouse model of BE, and human BE and EAC biopsies. Human non-dysplastic BE had the highest basal number of autophagic vesicles (AVs), while AVs were reduced in normal squamous cells and dysplastic BE cells, and nearly absent in EAC. To demonstrate a functional role for autophagy in BE pathogenesis, normal squamous (STR), non-dysplastic BE (CPA), dysplastic BE (CPD), and esophageal adenocarcinoma (OE19) cell lines were exposed to an acid pulse (pH3.5) followed by incubation in the presence or absence of chloroquine, an autophagy inhibitor. Acid exposure increased reactive oxygen species (ROS) levels in STR and CPA cells. Chloroquine alone had a small impact on intracellular ROS or cell survival. However, combination of chloroquine with the acid pulse resulted in a significant increase in ROS levels at 6 hours in STR and CPA cells, and increased cell death in all cell lines. These findings establish increased numbers of AVs in human BE compared to normal squamous or EAC, and suggest that autophagy functions to improve cell survival after acid reflux injury. Autophagy may thus play a critical role in BE pathogenesis and progression. PMID:26373456

CELL RESPIRATION STUDIES : II. A COMPARATIVE STUDY OF THE OXYGEN CONSUMPTION OF BLOOD FROM NORMAL INDIVIDUALS AND PATIENTS WITH INCREASED LEUCOCYTE COUNTS (SEPSIS; CHRONIC MYELOGENOUS LEUCEMIA).

PubMed

Daland, G A; Isaacs, R

1927-06-30

1. The oxygen consumption of blood of normal individuals, when the hemoglobin is saturated with oxygen, is practically zero within the limits of experimental error of the microspirometer used. 2. The oxygen consumed in a microspirometer by the blood of patients with chronic myelogenous leucemia with a high white blood cell count, and of one with leucocytosis from sepsis, was proportional to the number of adult polymorphonuclear neutrophils in the blood. 3. No correlation could be made between the rate of oxygen absorption and the total number of white blood cells in the blood, or the total number of immature cells, or the number of red blood cells, or the amount of oxyhemoglobin. 4. The blood of patients with chronic myelogenous leucemia continued to use oxygen in the microspirometer longer than that of normal individuals, and the hemoglobin, in the leucemic bloods, became desaturated even though exposed to air. 5. In blood in which the bulk. of the cells were immature and the mature cells few, the oxygen consumption was lower than in blood in which the mature cells predominated. The rate of oxygen consumption of the immature cells was relatively low as compared to the mature. 6. The slower rate of oxygen absorption by the immature leucocytes in chronic myelogenous leucemia as compared to the mature cells, places them, in accord with Warburg's reports, in the class of the malignant tissues in this respect rather than in the group of young or embryonic cells.

erbB expression changes in ethanol and 7, 12- dimethylbenz (a) anthracene-induced oral carcinogenesis

PubMed Central

Jacinto-Alemán, Luis F.; García-Carrancá, Alejandro; Leyba-Huerta, Elba R.; Zenteno-Galindo, Edgar; Jiménez-Farfán, María D.

2013-01-01

Objetive: The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster’s buccal pouch chemical carcinogenesis model. Study design: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann–Whitney U and Dunn’s test. Results: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histological normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dysplasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. Conclusion: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. The erbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA. Key words:erbB, 7,12- dimethylbenz(a)anthracene, oral squamous cell carcinoma. PMID:23229248

Effects of Charged Particles on Human Tumor Cells

PubMed Central

Held, Kathryn D.; Kawamura, Hidemasa; Kaminuma, Takuya; Paz, Athena Evalour S.; Yoshida, Yukari; Liu, Qi; Willers, Henning; Takahashi, Akihisa

2016-01-01

The use of charged particle therapy in cancer treatment is growing rapidly, in large part because the exquisite dose localization of charged particles allows for higher radiation doses to be given to tumor tissue while normal tissues are exposed to lower doses and decreased volumes of normal tissues are irradiated. In addition, charged particles heavier than protons have substantial potential clinical advantages because of their additional biological effects, including greater cell killing effectiveness, decreased radiation resistance of hypoxic cells in tumors, and reduced cell cycle dependence of radiation response. These biological advantages depend on many factors, such as endpoint, cell or tissue type, dose, dose rate or fractionation, charged particle type and energy, and oxygen concentration. This review summarizes the unique biological advantages of charged particle therapy and highlights recent research and areas of particular research needs, such as quantification of relative biological effectiveness (RBE) for various tumor types and radiation qualities, role of genetic background of tumor cells in determining response to charged particles, sensitivity of cancer stem-like cells to charged particles, role of charged particles in tumors with hypoxic fractions, and importance of fractionation, including use of hypofractionation, with charged particles. PMID:26904502

Sensitivity of cultured skin fibroblasts from patients with neurofibromatosis to DNA-damaging agents

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

Woods, W.G.; McKenzie, B.; Letourneau, M.A.

Neurofibromatosis (NF) is an autosomal dominant disorder associated with various constitutional abnormalities as well as a striking predisposition for malignant and nonmalignant neoplasms, both in cells originating in and not originating in the neural crest. We have examined the sensitivity of cultured skin fibroblasts from patients with neurofibromatosis to several types of DNA damage. Fibroblasts in Dulbecco's modified Eagle's medium were plated at 10(2) to 2 X 10(4) cells per 75 cm2 tissue culture plates, and exposed to various doses of gamma radiation (leads to DNA scission), actinomycin D, or mitomycin C. Cells were reincubated for 15 to 40 daysmore » until surviving colonies exhibited greater than 30-50 cells. Plates were then stained with 1% methylene blue and the colonies counted, with surviving fraction determined relative to plating efficiency. Nine skin fibroblast cell strains from normal individuals were studied as controls. One neurofibromatosis (NF) cell strain, SB23, exhibited normal sensitivity to all three DNA-damaging agents studied in early (7-8) and middle (12-13) in vitro passage. Strain GM0622, on the other hand, exhibited normal sensitivity to the three DNA-damaging agents studied at early passage, but showed a significant decrease in survival after exposure to both gamma radiation (D0 = 106 rad) and actinomycin D (D0 = 0.024 mcg/ml) with increasing passage. Strain GM1639 exhibited decreased survival after actinomycin D exposure at early passage (D0 = 0.017 mcg/ml), with normal survival after exposure to gamma radiation and mitomycin C at the same passage.« less

Erythroid progenitor cells (CFU-E*) from Friend virus-infected mice undergo VVFe suicide in vitro in the absence of added erythropoietin

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

Del Rizzo, D.F.; Axelrad, A.A.

The authors have investigated the effect of VVFe on the survival in suspension of erythropoietin (epo)-independent erythroid progenitor cells (CFU-E*) induced by Friend polycythemia virus (FV). Spleen cells from C3Hf/Bi mice previously infected with FV were exposed to carrier-free VVFe, and the survival of CFU-E* as a function of time in liquid medium was determined from the number of erythroid colonies that developed from these cells seeded in plasma cultures without added epo. The results showed that spleen CFU-E* were highly vulnerable to VVFe. Marrow CFU-E* behaved in a similar manner. The VVFe responsible for their suicide had been presentedmore » to the progenitor cells only during the 4-h period of incubation, after which they were washed and plated in excess nonradioactive iron. They therefore conclude that CFU-E* themselves, and not only their progeny, are capable of actively incorporating iron. Under the same conditions in the absence of added epo, the effect of VVFe on the survival of normal spleen or marrow CFU-E could not be assessed because two few normal CFU-E survived the incubation period. Normal bone marrow cells incubated in complete medium containing epo retained their capacity for erythrocytic colony formation, and CFU-E could then be shown to be vulnerable to VVFe. Thus, either the iron-incorporating system of normal CFU-E was inducible by epo, or else epo permitted survival of the CFU-E so that the activity of a constitutive iron-incorporating system could be recognized.« less

THE HIGH BACKGROUND RADIATION AREA IN RAMSAR IRAN: GEOLOGY, NORM, BIOLOGY, LNT, AND POSSIBLE REGULATORY FUN

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

Karam, P. A.

2002-02-25

The city of Ramsar Iran hosts some of the highest natural radiation levels on earth, and over 2000 people are exposed to radiation doses ranging from 1 to 26 rem per year. Curiously, inhabitants of this region seem to have no greater incidence of cancer than those in neighboring areas of normal background radiation levels, and preliminary studies suggest their blood cells experience fewer induced chromosomal abnormalities when exposed to 150 rem ''challenge'' doses of radiation than do the blood cells of their neighbors. This paper will briefly describe the unique geology that gives Ramsar its extraordinarily high background radiationmore » levels. It will then summarize the studies performed to date and will conclude by suggesting ways to incorporate these findings (if they are borne out by further testing) into future radiation protection standards.« less

Electroporation-Induced Cell Modifications Detected with THz Time-Domain Spectroscopy

NASA Astrophysics Data System (ADS)

Romeo, Stefania; Vernier, P. Thomas; Zeni, Olga

2018-04-01

Electroporation (electropermeabilization) increases the electrical conductivity of biological cell membranes and lowers transport barriers for normally impermeant materials. Molecular simulations suggest that electroporation begins with the reorganization of water and lipid head group dipoles in the phospholipid bilayer interface, driven by an externally applied electric field, and the evolution of the resulting defects into water-filled, lipid pores. The interior of the electroporated membrane thus contains water, which should provide a signature for detection of the electropermeabilized state. In this feasibility study, we use THz time-domain spectroscopy, a powerful tool for investigating biomolecular systems and their interactions with water, to detect electroporation in human cells subjected to permeabilizing pulsed electric fields (PEFs). The time-domain response of electroporated human monocytes was acquired with a commercial THz, time-domain spectrometer. For each sample, frequency spectra were calculated, and the absorption coefficient and refractive index were extracted in the frequency range between 0.2 and 1.5 THz. This analysis reveals a higher absorption of THz radiation by PEF-exposed cells, with respect to sham-exposed ones, consistent with the intrusion of water into the cell through the permeabilized membrane that is presumed to be associated with electroporation.

Microgravity Effects on Transendothelial Transport

NASA Technical Reports Server (NTRS)

Tarbell, John M.

1996-01-01

The Endothelial Cell (EC) layer which lines blood vessels from the aorta to the capillaries provides the principal barrier to transport of water and solutes between blood and underlying tissue. Endothelial cells are continuously exposed to the mechanical shearing force (shear stress) and normal force (pressure) imposed by flowing blood on their surface, and they are adapted to this mechanical environment. When the cardiovascular system is exposed to microgravity, the mechanical environmental of endothelial cells is perturbed drastically and the transport properties of EC layers are altered in response. We have shown recently that step changes in shear stress have an acute effect on transport properties of EC layers in a cell culture model, and several recent studies in different vessels of live animals have confirmed the shear-dependent transport properties of the endothelium. We hypothesize that alterations in mechanical forces induced by microgravity and their resultant influence on transendothelial transport of water and solutes are, in large measure, responsible for the characteristic cephalad fluid shift observed in humans experiencing microgravity. To study the effects of altered mechanical forces on transendothelial transport and to test pharmacologic agents as counter measures to microgravity induced fluid shifts we have proposed ground-based studies using well defined cell culture models.

Wnt5a Is Associated with Cigarette Smoke-Related Lung Carcinogenesis via Protein Kinase C

PubMed Central

Sung, Jae Sook; Ju, Hyun Jung; Kim, Hyun Kyung; Park, Kyong Hwa; Lee, Jong Won; Koh, In Song; Kim, Yeul Hong

2013-01-01

Wnt5a is overexpressed during the progression of human non-small cell lung cancer. However, the roles of Wnt5a during smoking-related lung carcinogenesis have not been clearly elucidated. We investigated the associations between Wnt5a and the early development of cigarette smoke related lung cancer using human bronchial epithelial (HBE) cells (NHBE, BEAS-2B, 1799, 1198 and 1170I) at different malignant stages established by exposure to cigarette smoke condensate (CSC). Abnormal up-regulation of Wnt5a mRNA and proteins was detected in CSC-exposed transformed 1198 and tumorigenic 1170I cells as compared with other non-CSC exposed HBE cells. Tumor tissues obtained from smokers showed higher Wnt5a expressions than matched normal tissues. In non-CSC exposed 1799 cells, treatment of recombinant Wnt5a caused the activations of PKC and Akt, and the blockage of Wnt5a and PKC significantly decreased the viabilities of CSC-transformed 1198 cells expressing high levels of Wnt5a. This reduced cell survival rate was associated with increased apoptosis via the down-regulation of Bcl2 and the induction of cleaved poly ADP-ribose polymerase. Moreover, CSC-treated 1799 cells showed induction of Wnt5a expression and enhanced colony-forming capacity. The CSC-induced colony forming efficiency was suppressed by the co-incubation with a PKC inhibitor. In conclusion, these results suggest that cigarette smoke induces Wnt5a-coupled PKC activity during lung carcinogenesis, which causes Akt activity and anti-apoptosis in lung cancer. Therefore, current study provides novel clues for the crucial role of Wnt5a in the smoking-related lung carcinogenesis. PMID:23349696

Wnt5a is associated with cigarette smoke-related lung carcinogenesis via protein kinase C.

PubMed

Whang, Young Mi; Jo, Ukhyun; Sung, Jae Sook; Ju, Hyun Jung; Kim, Hyun Kyung; Park, Kyong Hwa; Lee, Jong Won; Koh, In Song; Kim, Yeul Hong

2013-01-01

Wnt5a is overexpressed during the progression of human non-small cell lung cancer. However, the roles of Wnt5a during smoking-related lung carcinogenesis have not been clearly elucidated. We investigated the associations between Wnt5a and the early development of cigarette smoke related lung cancer using human bronchial epithelial (HBE) cells (NHBE, BEAS-2B, 1799, 1198 and 1170I) at different malignant stages established by exposure to cigarette smoke condensate (CSC). Abnormal up-regulation of Wnt5a mRNA and proteins was detected in CSC-exposed transformed 1198 and tumorigenic 1170I cells as compared with other non-CSC exposed HBE cells. Tumor tissues obtained from smokers showed higher Wnt5a expressions than matched normal tissues. In non-CSC exposed 1799 cells, treatment of recombinant Wnt5a caused the activations of PKC and Akt, and the blockage of Wnt5a and PKC significantly decreased the viabilities of CSC-transformed 1198 cells expressing high levels of Wnt5a. This reduced cell survival rate was associated with increased apoptosis via the down-regulation of Bcl2 and the induction of cleaved poly ADP-ribose polymerase. Moreover, CSC-treated 1799 cells showed induction of Wnt5a expression and enhanced colony-forming capacity. The CSC-induced colony forming efficiency was suppressed by the co-incubation with a PKC inhibitor. In conclusion, these results suggest that cigarette smoke induces Wnt5a-coupled PKC activity during lung carcinogenesis, which causes Akt activity and anti-apoptosis in lung cancer. Therefore, current study provides novel clues for the crucial role of Wnt5a in the smoking-related lung carcinogenesis.

Fasting inhibits hepatic stellate cells activation and potentiates anti-cancer activity of Sorafenib in hepatocellular cancer cells.

PubMed

Lo Re, Oriana; Panebianco, Concetta; Porto, Stefania; Cervi, Carlo; Rappa, Francesca; Di Biase, Stefano; Caraglia, Michele; Pazienza, Valerio; Vinciguerra, Manlio

2018-02-01

Hepatocellular carcinoma (HCC) has a poor outcome. Most HCCs develop in the context of liver fibrosis and cirrhosis caused by chronic inflammation. Short-term fasting approaches enhance the activity of chemotherapy in preclinical cancer models, other than HCC. Multi-tyrosine kinase inhibitor Sorafenib is the mainstay of treatment in HCC. However, its benefit is frequently short-lived. Whether fasting can alleviate liver fibrosis and whether combining fasting with Sorafenib is beneficial remains unknown. A 24 hr fasting (2% serum, 0.1% glucose)-induced changes on human hepatic stellate cells (HSC) LX-2 proliferation/viability/cell cycle were assessed by MTT and flow cytometry. Expression of lypolysaccharide (LPS)-induced activation markers (vimentin, αSMA) was evaluated by qPCR and immunoblotting. Liver fibrosis and inflammation were evaluated in a mouse model of steatohepatitis exposed to cycles of fasting, by histological and biochemical analyses. A 24 hr fasting-induced changes were also analyzed on the proliferation/viability/glucose uptake of human HCC cells exposed to Sorafenib. An expression panel of genes involved in survival, inflammation, and metabolism was examined by qPCR in HCC cells exposed to fasting and/or Sorafenib. Fasting decreased the proliferation and the activation of HSC. Repeated cycles of short term starvation were safe in mice but did not improve fibrosis. Fasting synergized with Sorafenib in hampering HCC cell growth and glucose uptake. Finally, fasting normalized the expression levels of genes which are commonly altered by Sorafenib in HCC cells. Fasting or fasting-mimicking diet diets should be evaluated in preclinical studies as a mean to potentiate the activity of Sorafenib in clinical use. © 2017 Wiley Periodicals, Inc.

Characterization of the differential response of endothelial cells exposed to normal and elevated laminar shear stress.

PubMed

White, Stephen J; Hayes, Elaine M; Lehoux, Stéphanie; Jeremy, Jamie Y; Horrevoets, Anton J G; Newby, Andrew C

2011-11-01

Most acute coronary events occur in the upstream region of stenotic atherosclerotic plaques that experience laminar shear stress (LSS) elevated above normal physiological levels. Many studies have described the atheroprotective effect on endothelial behavior of normal physiological LSS (approximately 15 dynes/cm(2)) compared to static or oscillatory shear stress (OSS), but it is unknown whether the levels of elevated shear stress imposed by a stenotic plaque would preserve, enhance or reverse this effect. Therefore we used transcriptomics and related functional analyses to compare human endothelial cells exposed to laminar shear stress of 15 (LSS15-normal) or 75 dynes/cm(2) (LSS75-elevated). LSS75 upregulated expression of 145 and downregulated expression of 158 genes more than twofold relative to LSS15. Modulation of the metallothioneins (MT1-G, -M, -X) and NADPH oxidase subunits (NOX2, NOX4, NOX5, and p67phox) accompanied suppression of reactive oxygen species production at LSS75. Shear induced changes in dual specificity phosphatases (DUSPs 1, 5, 8, and 16 increasing and DUSPs 6 and 23 decreasing) were observed as well as reduced ERK1/2 but increased p38 MAP kinase phosphorylation. Amongst vasoactive substances, endothelin-1 expression decreased whereas vasoactive intestinal peptide (VIP) and prostacyclin expression increased, despite which intracellular cAMP levels were reduced. Promoter analysis by rVISTA identified a significant over representation of ATF and Nrf2 transcription factor binding sites in genes upregulated by LSS75 compared to LSS15. In summary, LSS75 induced a specific change in behavior, modifying gene expression, reducing ROS levels, altering MAP kinase signaling and reducing cAMP levels, opening multiple avenues for future study. Copyright © 2011 Wiley-Liss, Inc.

Amniotic fluid derived mesenchymal stromal cells augment fetal lung growth in a nitrofen explant model.

PubMed

Di Bernardo, Julie; Maiden, Michael M; Hershenson, Marc B; Kunisaki, Shaun M

2014-06-01

Recent experimental work suggests the therapeutic role of mesenchymal stromal cells (MSCs) during lung morphogenesis. The purpose of this study was to investigate the potential paracrine effects of amniotic fluid-derived MSCs (AF-MSCs) on fetal lung growth in a nitrofen explant model. Pregnant Sprague-Dawley dams were gavage fed nitrofen on gestational day 9.5 (E9.5). E14.5 lung explants were subsequently harvested and cultured ex vivo for three days on filter membranes in conditioned media from rat AF-MSCs isolated from control (AF-Ctr) or nitrofen-exposed (AF-Nitro) dams. The lungs were analyzed morphometrically and by quantitative gene expression. Although there were no significant differences in total lung surface area among hypoplastic lungs, there were significant increases in terminal budding among E14.5+3 nitrofen explants exposed to AF-Ctr compared to explants exposed to medium alone (58.8±8.4 vs. 39.0±10.0 terminal buds, respectively; p<0.05). In contrast, lungs cultured in AF-Nitro medium failed to augment terminal budding. Nitrofen explants exposed to AF-Ctr showed significant upregulation of surfactant protein C to levels observed in normal fetal lungs. AF-MSCs can augment branching morphogenesis and lung epithelial maturation in a fetal explant model of pulmonary hypoplasia. Cell therapy using donor-derived AF-MSCs may represent a novel strategy for the treatment of fetal congenital diaphragmatic hernia. Copyright © 2014 Elsevier Inc. All rights reserved.

Mesenchymal stromal cell derived extracellular vesicles rescue radiation damage to murine marrow hematopoietic cells

PubMed Central

Wen, Sicheng; Dooner, Mark; Cheng, Yan; Papa, Elaine; Del Tatto, Michael; Pereira, Mandy; Deng, Yanhui; Goldberg, Laura; Aliotta, Jason; Chatterjee, Devasis; Stewart, Connor; Carpanetto, Andrea; Collino, Federica; Bruno, Stefania; Camussi, Giovanni; Quesenberry, Peter

2016-01-01

Mesenchymal stromal cells (MSC) have been shown to reverse radiation damage to marrow stem cells. We have evaluated the capacity of MSC-derived extracellular vesicles (MSC-EVs) to mitigate radiation injury to marrow stem cells at 4 hours to 7 days after irradiation. Significant restoration of marrow stem cell engraftment at 4, 24 and 168 hours post-irradiation by exposure to MSC-EVs was observed at 3 weeks to 9 months after transplant and further confirmed by secondary engraftment. Intravenous injection of MSC-EVs to 500cGy exposed mice led to partial recovery of peripheral blood counts and restoration of the engraftment of marrow. The murine hematopoietic cell line, FDC-P1 exposed to 500 cGy, showed reversal of growth inhibition, DNA damage and apoptosis on exposure to murine or human MSC-EVs. Both murine and human MSC-EVs reverse radiation damage to murine marrow cells and stimulate normal murine marrow stem cell/progenitors to proliferate. A preparation with both exosomes and microvesicles was found to be superior to either microvesicles or exosomes alone. Biologic activity was seen in freshly isolated vesicles and in vesicles stored for up to 6 months in 10% DMSO at −80°C. These studies indicate that MSC-EVs can reverse radiation damage to bone marrow stem cells. PMID:27150009

Elevated Cell Wall Chitin in Candida albicans Confers Echinocandin Resistance In Vivo

PubMed Central

Lee, Keunsook K.; MacCallum, Donna M.; Jacobsen, Mette D.; Walker, Louise A.; Odds, Frank C.

2012-01-01

Candida albicans cells with increased cell wall chitin have reduced echinocandin susceptibility in vitro. The aim of this study was to investigate whether C. albicans cells with elevated chitin levels have reduced echinocandin susceptibility in vivo. BALB/c mice were infected with C. albicans cells with normal chitin levels and compared to mice infected with high-chitin cells. Caspofungin therapy was initiated at 24 h postinfection. Mice infected with chitin-normal cells were successfully treated with caspofungin, as indicated by reduced kidney fungal burdens, reduced weight loss, and decreased C. albicans density in kidney lesions. In contrast, mice infected with high-chitin C. albicans cells were less susceptible to caspofungin, as they had higher kidney fungal burdens and greater weight loss during early infection. Cells recovered from mouse kidneys at 24 h postinfection with high-chitin cells had 1.6-fold higher chitin levels than cells from mice infected with chitin-normal cells and maintained a significantly reduced susceptibility to caspofungin when tested in vitro. At 48 h postinfection, caspofungin treatment induced a further increase in chitin content of C. albicans cells harvested from kidneys compared to saline treatment. Some of the recovered clones had acquired, at a low frequency, a point mutation in FKS1 resulting in a S645Y amino acid substitution, a mutation known to confer echinocandin resistance. This occurred even in cells that had not been exposed to caspofungin. Our results suggest that the efficacy of caspofungin against C. albicans was reduced in vivo due to either elevation of chitin levels in the cell wall or acquisition of FKS1 point mutations. PMID:21986821

Role of carbonate in the cytotoxicity of carboplatin.

PubMed

Di Pasqua, Anthony J; Goodisman, Jerry; Kerwood, Deborah J; Toms, Bonnie B; Dubowy, Ronald L; Dabrowiak, James C

2007-06-01

Carboplatin, [Pt(NH3)2(CBDCA-O,O')], 1, where CBDCA is cyclobutane-1,1-dicarboxylate, is used against ovarian, lung, and other types of cancer. We recently showed (Di Pasqua et al. (2006) Chem. Res. Toxicol. 19, 139-149) that carboplatin reacts with carbonate under conditions that simulate therapy to produce carbonato carboplatin, cis-[Pt(NH3)2(O-CBDCA)(CO3)]2-, 2. We use 13C and 1H NMR and UV-visible absorption spectroscopy to show that solutions containing carboplatin that have been aged in carbonate buffer under various conditions contain 1, 2, and other compounds. We then show that aging carboplatin in carbonate produces compounds that are more toxic to human neuroblastoma (SK-N-SH), proximal renal tubule (HK-2) and Namalwa-luc Burkitt's lymphoma (BL) cells than carboplatin alone. Moreover, increasing the aging time increases the cytotoxicity of the platinum solutions as measured by the increase in cell death. Although HK-2 cells experience a large loss in survival upon exposure to carbonato forms of the drug, they have the highest values of IC50 of the three cell lines studied, so that HK-2 cells remain the most resistant to the toxic effects of the carbonato forms in the culture medium. This is consistent with the well-known low renal toxicity observed for carboplatin in therapy. The uptake rates for normal Jurkat cells (NJ) and cisplatin-resistant Jurkat cells (RJ), measured by inductively coupled plasma mass spectrometry (ICP-MS), are 16.6 +/- 4.2 and 12.3 +/- 4.8 amol of Pt h-1 cell-1, respectively, when exposed to carboplatin alone. However, when these cells are exposed to carboplatin that has been aged in carbonate media, normal Jurkat cells strongly bind/take up Pt at a rate of 14.5 +/- 4.1 amol of Pt h-1 cell-1, while resistant cells strongly bind/take up 5.1 +/- 3.3 amol of Pt h-1 cell-1. Collectively, these studies show that carboplatin carbonato species may play a major role in the cytotoxicity and uptake of carboplatin by cells.

Toll-like Receptor 2 Signalling and the Lysosomal Machinery in Barrett's Esophagus.

PubMed

Verbeek, Romy E; Siersema, Peter D; Vleggaar, Frank P; Ten Kate, Fiebo J; Posthuma, George; Souza, Rhonda F; de Haan, Judith; van Baal, Jantine W P M

2016-09-01

Inflammation plays an important role in the development of esophageal adenocarcinoma and its metaplastic precursor lesion, Barrett's esophagus. Toll-like receptor (TLR) 2 signalling and lysosomal function have been linked to inflammation-associated carcinogenesis. We examined the expression of TLR2 in the esophagus and the effect of long-term TLR2 activation on morphological changes and expression of factors involved in lysosomal function in a Barrett's esophagus epithelium cell line. TLR2 expression in normal squamous esophagus, reflux esophagitis, Barrett's esophagus and esophageal adenocarcinoma biopsies was assessed with Q-RT-PCR, in situ hybridization and immunohistochemistry. Barrett's esophagus epithelium cells (BAR-T) were incubated with acid and bile salts in the presence or absence of the TLR2 agonist Pam3CSK4 for a period up to 4 weeks. Morphological changes were assessed with electron microscopy, while Q-RT-PCR was used to determine the expression of lysosomal enzymes (Cathepsin B and C) and factors involved in endocytosis (LAMP-1 and M6PR) and autophagy (LC3 and Rab7). TLR2 was expressed in normal squamous esophagus, reflux esophagitis, Barrett's esophagus but was most prominent in esophageal adenocarcinoma. Long-term TLR2 activation in acid and bile salts exposed BAR-T cells resulted in more and larger lysosomes, more mitochondria and increased expression of LAMP-1, M6PR, Cathepsin B and C when compared to BAR-T cells incubated with acid and bile salts but no TLR2 agonist. Factors associated with autophagy (LC3 and Rab7) expression remained largely unchanged. Activation of TLR2 in acid and bile salts exposed Barrett epithelium cells resulted in an increased number of mitochondria and lysosomes and increased expression of lysosomal enzymes and factors involved in endocytosis.

Arrested neural and advanced mesenchymal differentiation of glioblastoma cells-comparative study with neural progenitors

PubMed Central

2009-01-01

Background Although features of variable differentiation in glioblastoma cell cultures have been reported, a comparative analysis of differentiation properties of normal neural GFAP positive progenitors, and those shown by glioblastoma cells, has not been performed. Methods Following methods were used to compare glioblastoma cells and GFAP+NNP (NHA): exposure to neural differentiation medium, exposure to adipogenic and osteogenic medium, western blot analysis, immunocytochemistry, single cell assay, BrdU incorporation assay. To characterize glioblastoma cells EGFR amplification analysis, LOH/MSI analysis, and P53 nucleotide sequence analysis were performed. Results In vitro differentiation of cancer cells derived from eight glioblastomas was compared with GFAP-positive normal neural progenitors (GFAP+NNP). Prior to exposure to differentiation medium, both types of cells showed similar multilineage phenotype (CD44+/MAP2+/GFAP+/Vimentin+/Beta III-tubulin+/Fibronectin+) and were positive for SOX-2 and Nestin. In contrast to GFAP+NNP, an efficient differentiation arrest was observed in all cell lines isolated from glioblastomas. Nevertheless, a subpopulation of cells isolated from four glioblastomas differentiated after serum-starvation with varying efficiency into derivatives indistinguishable from the neural derivatives of GFAP+NNP. Moreover, the cells derived from a majority of glioblastomas (7 out of 8), as well as GFAP+NNP, showed features of mesenchymal differentiation when exposed to medium with serum. Conclusion Our results showed that stable co-expression of multilineage markers by glioblastoma cells resulted from differentiation arrest. According to our data up to 95% of glioblastoma cells can present in vitro multilineage phenotype. The mesenchymal differentiation of glioblastoma cells is advanced and similar to mesenchymal differentiation of normal neural progenitors GFAP+NNP. PMID:19216795

9 CFR 311.23 - Tapeworm cysts (cysticercus bovis) in cattle.

Code of Federal Regulations, 2010 CFR

2010-01-01

... OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION... exposed during normal dressing operations, they are found in at least two of the sites exposed by (i) an..., esophagus, tongue, and musculature exposed during normal dressing operations, may be passed for human food...

Surface characteristics of spacecraft components affect the aggregation of microorganisms and may lead to different survival rates of bacteria on Mars landers.

PubMed

Schuerger, Andrew C; Richards, Jeffrey T; Hintze, Paul E; Kern, Roger G

2005-08-01

Layers of dormant endospores of Bacillus subtilis HA101 were applied to eight different spacecraft materials and exposed to martian conditions of low pressure (8.5 mbar), low temperature (-10 degrees C), and high CO(2) gas composition and irradiated with a Mars-normal ultraviolet (UV-visible- near-infrared spectrum. Bacterial layers were exposed to either 1 min or 1 h of Mars-normal UV irradiation, which simulated clear-sky conditions on equatorial Mars (0.1 tau). When exposed to 1 min of Mars UV irradiation, the numbers of viable endospores of B. subtilis were reduced three to four orders of magnitude for two brands of aluminum (Al), stainless steel, chemfilm-treated Al, clear-anodized Al, and black-anodized Al coupons. In contrast, bacterial survival was reduced only one to two orders of magnitude for endospores on the non-metal materials astroquartz and graphite composite when bacterial endospores were exposed to 1 min of Mars UV irradiation. When bacterial monolayers were exposed to 1 h of Mars UV irradiation, no viable bacteria were recovered from the six metal coupons listed above. In contrast, bacterial survival was reduced only two to three orders of magnitude for spore layers on astroquartz and graphite composite exposed to 1 h of Mars UV irradiation. Scanning electron microscopy images of the bacterial monolayers on all eight spacecraft materials revealed that endospores of B. subtilis formed large aggregates of multilayered spores on astroquartz and graphite composite, but not on the other six spacecraft materials. It is likely that the formation of multilayered aggregates of endospores on astroquartz and graphite composite is responsible for the enhanced survival of bacterial cells on these materials.

Surface characteristics of spacecraft components affect the aggregation of microorganisms and may lead to different survival rates of bacteria on Mars landers

NASA Technical Reports Server (NTRS)

Schuerger, Andrew C.; Richards, Jeffrey T.; Hintze, Paul E.; Kern, Roger G.

2005-01-01

Layers of dormant endospores of Bacillus subtilis HA101 were applied to eight different spacecraft materials and exposed to martian conditions of low pressure (8.5 mbar), low temperature (-10 degrees C), and high CO(2) gas composition and irradiated with a Mars-normal ultraviolet (UV-visible- near-infrared spectrum. Bacterial layers were exposed to either 1 min or 1 h of Mars-normal UV irradiation, which simulated clear-sky conditions on equatorial Mars (0.1 tau). When exposed to 1 min of Mars UV irradiation, the numbers of viable endospores of B. subtilis were reduced three to four orders of magnitude for two brands of aluminum (Al), stainless steel, chemfilm-treated Al, clear-anodized Al, and black-anodized Al coupons. In contrast, bacterial survival was reduced only one to two orders of magnitude for endospores on the non-metal materials astroquartz and graphite composite when bacterial endospores were exposed to 1 min of Mars UV irradiation. When bacterial monolayers were exposed to 1 h of Mars UV irradiation, no viable bacteria were recovered from the six metal coupons listed above. In contrast, bacterial survival was reduced only two to three orders of magnitude for spore layers on astroquartz and graphite composite exposed to 1 h of Mars UV irradiation. Scanning electron microscopy images of the bacterial monolayers on all eight spacecraft materials revealed that endospores of B. subtilis formed large aggregates of multilayered spores on astroquartz and graphite composite, but not on the other six spacecraft materials. It is likely that the formation of multilayered aggregates of endospores on astroquartz and graphite composite is responsible for the enhanced survival of bacterial cells on these materials.

Antibiotic tigecycline enhances cisplatin activity against human hepatocellular carcinoma through inducing mitochondrial dysfunction and oxidative damage

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

Tan, Jun; Song, Meijun; Zhou, Mi

Targeting mitochondrial metabolism has been recently demonstrated to be a promising therapeutic strategy for the treatment of various cancer. In this work, we demonstrate that antibiotic tigecycline is selectively against hepatocellular carcinoma (HCC) through inducing mitochondrial dysfunction and oxidative damage. Tigecycline is more effective in inhibiting proliferation and inducing apoptosis of HCC than normal liver cells. Importantly, tigecycline significantly enhances the inhibitory effects of chemotherapeutic drug cisplatin in HCC in vitro and in vivo. Mechanistically, tigecycline specifically inhibits mitochondrial translation as shown by the decreased protein levels of Cox-1 and -2 but not Cox-4 or Grp78, and increased mRNA levels of Cox-1more » and -2 but not Cox-4 in HCC cells exposed to tigecycline. In addition, tigecycline significantly induces mitochondrial dysfunction in HCC cells via decreasing mitochondrial membrane potential, complex I and IV activities, mitochondrial respiration and ATP levels. Tigecycline also increases levels of mitochondrial superoxide, hydrogen peroxide and ROS levels. Consistent with oxidative stress, oxidative damage on DNA, protein and lipid are also observed in tigecycline-treated cells. Importantly, antioxidant N-acetyl-L-cysteine (NAC) reverses the effects of tigecycline, suggesting that oxidative stress is required for the action of tigecycline in HCC cells. We further show that HCC cells have higher level of mitochondrial biogenesis than normal liver cells which might explain the different sensitivity to tigecycline between HCC and normal liver cells. Our work is the first to demonstrate that tigecycline is a promising candidate for HCC treatment and highlight the therapeutic value of targeting mitochondrial metabolism in HCC. - Highlights: • Tigecycline selectively targets HCC in vitro and in vivo. • Tigecycline enhances HCC cell response to chemotherapeutic drug. • Tigecycline inhibits mitochondrial translation and functions in HCC cells. • Tigecycline induces oxidative stress and damage in HCC cells. • Mitochondrial biogenesis and respiration is higher in HCC than normal liver cells.« less

Raman spectroscopy for diagnosis of glioblastoma multiforme

NASA Astrophysics Data System (ADS)

Clary, Candace Elise

Glioblastoma multiforme (GBM), the most common and most fatal malignant brain tumor, is highly infiltrative and incurable. Although improved prognosis has been demonstrated by surgically resecting the bulk tumor, a lack of clear borders at the tumor margins complicates the selection decision during surgery. This dissertation investigates the potential of Raman spectroscopy for distinguishing between normal and malignant brain tissue and sets the groundwork for a surgical diagnostic guide for resection of gross malignant gliomas. These studies revealed that Raman spectroscopy was capable of discriminating between normal scid mouse brain tissue and human xenograft tumors induced in those mice. The spectra of normal and malignant tissue were normalized by dividing by the respective magnitudes of the peaks near 1440 cm -1. Spectral differences include the shape of the broad peaks near 1440 cm-1 and 1660 cm-1 and the relative magnitudes of the peaks at 1264 cm-1, 1287 cm-1, 1297 cm-1, 1556 cm -1, 1586 cm-1, 1614 cm-1, and 1683 cm-1. From these studies emerged questions regarding how to objectively normalize and compare spectra for future automation. Some differences in the Raman spectra were shown to be inherent in the disease states of the cells themselves via differences in the Raman spectra of normal human astrocytes in culture and cultured cells derived from GBM tumors. The spectra of astrocytes and glioma cells were normalized by dividing by the respective magnitudes of the peaks near 1450 cm-1. The differences between the Raman spectra of normal and transformed cells include the ratio of the 1450 cm-1/1650 cm-1 peaks and the relative magnitudes of the peaks at 1181 cm-1, 1191 cm-1, 1225 cm-1, 1263 cm -1, 1300 cm-1, 1336 cm-1, 1477 cm-1, 1494 cm-1, and 1695 cm -1. Previous Raman spectroscopic studies of biological cells have shown that the magnitude of the Raman signal decreases over time, indicating sample damage. Cells exposed to laser excitation at similar power densities were evaluated in terms of mitochondrial oxidative/reductive activity as well as protein, RNA, and DNA syntheses. Although cell death was not significant, the cells' abilities to synthesize DNA, RNA, and protein were profoundly affected by the laser irradiation.

Mitochondria DNA replication and DNA methylation in the metabolic memory associated with continued progression of diabetic retinopathy.

PubMed

Tewari, Shikha; Zhong, Qing; Santos, Julia M; Kowluru, Renu A

2012-07-24

Diabetic retinopathy fails to halt after cessation of hyperglycemic insult, and a vicious cycle of mitochondria damage continues. The aim of our study was to investigate the effect of termination of hyperglycemia on retinal mtDNA replication, and elucidate the mechanism responsible for the continued mtDNA damage. Polymerase gamma 1 (POLG1), the catalytic subunit of the mitochondrial DNA replication enzyme, and the damage to the displacement loop region of mtDNA (D-loop) were analyzed in the retina from streptozotocin-diabetic rats maintained in poor glycemic control (PC, glycated hemoglobin ∼11%) or in good glycemic control (GC, glycated hemoglobin ∼6%) for 6 months, or in PC for three months followed by GC for three months (Rev). To understand the mechanism DNA methylation status of POLG1 promoter was investigated by methylation-specific PCR. The key parameters were confirmed in the isolated retinal endothelial cells exposed to high glucose, followed by normal glucose. POLG1 continued to be down-regulated, the D-loop region damaged, and the CpG islands at the regulatory region of POLG hyper-methylated even after three months of GC that had followed three months of PC (Rev group). Similar results were observed in the retinal endothelial cells exposed to normal glucose after being exposed to high glucose. Continued hypermethylation of the CpG sites at the regulatory region of POLG affects its binding to the mtDNA, compromising the transcriptional activity. Modulation of DNA methylation using pharmaceutic or molecular means could help maintain mitochondria homeostasis, and prevent further progression of diabetic retinopathy.

Effects of Magnetic Field on Biological Cells and Applications

NASA Astrophysics Data System (ADS)

Chen, Ching-Jen

2001-03-01

While there has been extensive research performed in the physics of magnetic fields and the physics and chemistry in life sciences, independent of each other, there has been a paucity of scientific research and development investigating the possible applications of magnetic fields in life sciences. The focus of this presentation is to present the stimulation mechanism by which magnetic fields affect (a) yeast cells (b) plant cells and (c) mammalian normal and cancer cells. Recently we have found that the Saccharomyces Cerevsa yeast growth increases by about 30to a 1 tesla field and the production of CO2 increases by about 30of yeast metabolism may be due to an increase in intercellular interaction and protein channel alignment, the introduction of an alteration in the DNA from the magnetic field exposure or a combination of these mechanisms. We also have found that the application of high magnetic fields (1 tesla and above) can have marked effects on the germination and growth of plants, especially corn, beans and peas. This finding has opened up the possibility of technology developments in botanical growth systems to accelerate seed germination and crop harvesting. Most recently we have investigated the application of high magnetic fields on leukemia, CaCoII and HEP G2 cancer cell lines. We found that when leukemia are exposed to a 12 tesla field for 2 hours has an increase in cell death by about 30that were not exposed to the magnetic field. Viability of CaCoII cells sandwiched between permanent magnets of maximum strength of 1.2 tesla was measured. A decrease in viable cells by 33unexposed cells. HSP 70 was measured for HEPG2 cells that were exposed to permanent magnetic field of 1.2 tesla for 40 minutes and for unexposed cells. It was found that the exposed cells produce 19 times more HSP70 compared to unexposed cells. Our results together with other investigators report suggest a strong evidence of a reduction in the cell growth rate for cancer cells when subjected to high magnetic field. Devices that utilize an applied steady magnetic filed in it operation such as devices for blood component separation and diagnostic sensors have been developed.

High load of Merkel cell polyomavirus DNA detected in the normal skin of Japanese patients with Merkel cell carcinoma.

PubMed

Hashida, Yumiko; Nakajima, Kimiko; Nakajima, Hideki; Shiga, Takeo; Tanaka, Moe; Murakami, Masanao; Matsuzaki, Shigenobu; Naganuma, Seiji; Kuroda, Naoki; Seki, Yasutaka; Katano, Harutaka; Sano, Shigetoshi; Daibata, Masanori

2016-09-01

Although Merkel cell polyomavirus (MCPyV) has the potential to cause Merkel cell carcinoma (MCC), it is also found in the normal skin of healthy individuals. However, the mechanism for transformation of MCPyV to an oncogenic form is unknown. To investigate the levels of MCPyV infection in the normal skin patients with MCC compared with those in a control cohort. We studied a total of six Japanese patients with cutaneous MCC. Sun-exposed and sun-unexposed skin swabs were obtained and analyzed for MCPyV loads using quantitative real-time polymerase chain reaction. At first, we found a patient with MCC carrying an extremely high load of MCPyV DNA in normal skin. This unique case prompted us to further explore the levels of MCPyV as skin microbiota in patients with MCC. We showed that MCPyV DNA levels were significantly higher in swabs obtained from normal skin samples of six patients with MCC compared with those from 30 age-matched healthy individuals and 19 patients with other cutaneous cancers. Whereas MCPyV strains obtained from the normal skin of patients with MCC had gene sequences without structural alterations, sequences of the tumor-derived strains showed truncating mutations or deletions. Although the number of patients with MCC studied was small, our findings suggest that MCC may occur with a background of high MCPyV load in the skin, and are expected to stimulate further studies on whether such skin virome levels could be one of predictive markers for the development of MCC. Copyright © 2016 Elsevier B.V. All rights reserved.

TBT Effects on the Development of Intersex (Ovotestis) in Female Fresh Water Prawn Macrobrachium rosenbergii

PubMed Central

Peranandam, Revathi; Palanisamy, Iyapparaj; Lourdaraj, Arockia Vasanthi; Natesan, Munuswamy; Vimalananthan, Arun Prasanna; Thangaiyan, Suganya; Perumal, Anantharaman; Muthukalingan, Krishnan

2014-01-01

The impact of tributyltin (TBT) on the female gonad and the endocrine system in Macrobrachium rosenbergii was studied. Prawns were exposed to environmentally realistic concentrations of 10, 100, and 1000 ng/L of TBT for 6 months. Dose dependent effects were noticed in TBT exposed prawns. At 1000 ng/L TBT caused ovotestis formation (formation of male germ cells in ovary). Presence immature oocytes, fusion of developing oocytes, increase in interstitial connective tissues, and its modification into tubular like structure and abundance of spermatogonia in the ovary of TBT treated prawns. The control prawn ovary showed normal architecture of cellular organelles such as mature oocytes with type 2 yolk globules, lipid droplets, normal appearance of yolk envelop, and uniformly arranged microvilli. On the other hand, type 1 yolk globules, reduced size of microvilli, spermatogonial cells in ovary, spermatogonia with centrally located nucleus, and chromatin distribution throughout the nucleoplasm were present in the TBT treated group. Immunofluorescence staining indicated a reduction in vitellin content in ovary of TBT treated prawn. Moreover, TBT had inhibited the vitellogenesis by causing hormonal imbalance in M. rosenbergii. Thus, the present investigation demonstrates that TBT substantially affects sexual differentiation and gonadal development in M. rosenbergii. PMID:25121096

Antioxidant and antiapoptotic activities of Calotropis procera latex on Catfish (Clarias gariepinus) exposed to toxic 4-nonylphenol.

PubMed

Sayed, Alaa El-Din H; Mohamed, Nadia H; Ismail, Mady A; Abdel-Mageed, Wael M; Shoreit, Ahmed A M

2016-06-01

Calotropis procera L. is known as medicinal plant. The Phytochemical analyzes of its latex revealed that it possessed antioxidants, namely terpenes, phenolic compounds and cardenolides, flavonoids and saponins, while tannins, alkaloids and resin were absent in moderate to high concentration. In the present study, the role of latex of Calotropis procera as antioxidant and antiapoptotic was reported. To carry out this aim, fishes were exposed to 100 µg l(-1) 4-nonylphenol as chemical pollutant. The enzymes, superoxidase dismutase, catalase, acetlycholinstrase (AchE), glutathione s-transferase, cortisol, G6PDH) and apoptotic cells increased significantly (p<0.05) accompanied by irregular disturbance of (Na(+), K(+)) ions in the presence of 4-nonylphenol. On the other hand, these enzymes, ions, and apoptotic cells decreased normally and significantly (p<0.05) in the presence of latex. Total phenol content, total capacity antioxidant, reducing power decrease significantly (p<0.05) in the presence of 4-nonylphenol and increase normally in the presence of latex. Latex was used for the first time to protect catfish after 4-nonylphenol exposure. Our study confirms that crude latex of Calotropis procera possessed antioxidant and antiapoptotic activities against the toxicity of 4-Nonylphenol. Copyright © 2016 Elsevier Inc. All rights reserved.

TBT effects on the development of intersex (ovotestis) in female fresh water prawn Macrobrachium rosenbergii.

PubMed

Peranandam, Revathi; Palanisamy, Iyapparaj; Lourdaraj, Arockia Vasanthi; Natesan, Munuswamy; Vimalananthan, Arun Prasanna; Thangaiyan, Suganya; Perumal, Anantharaman; Muthukalingan, Krishnan

2014-01-01

The impact of tributyltin (TBT) on the female gonad and the endocrine system in Macrobrachium rosenbergii was studied. Prawns were exposed to environmentally realistic concentrations of 10, 100, and 1000 ng/L of TBT for 6 months. Dose dependent effects were noticed in TBT exposed prawns. At 1000 ng/L TBT caused ovotestis formation (formation of male germ cells in ovary). Presence immature oocytes, fusion of developing oocytes, increase in interstitial connective tissues, and its modification into tubular like structure and abundance of spermatogonia in the ovary of TBT treated prawns. The control prawn ovary showed normal architecture of cellular organelles such as mature oocytes with type 2 yolk globules, lipid droplets, normal appearance of yolk envelop, and uniformly arranged microvilli. On the other hand, type 1 yolk globules, reduced size of microvilli, spermatogonial cells in ovary, spermatogonia with centrally located nucleus, and chromatin distribution throughout the nucleoplasm were present in the TBT treated group. Immunofluorescence staining indicated a reduction in vitellin content in ovary of TBT treated prawn. Moreover, TBT had inhibited the vitellogenesis by causing hormonal imbalance in M. rosenbergii. Thus, the present investigation demonstrates that TBT substantially affects sexual differentiation and gonadal development in M. rosenbergii.

Influence of the dark/light rhythm on the effects of UV radiation in the eyestalk of the crab Neohelice granulata.

PubMed

Vargas, Marcelo Alves; Geish, Marcio Alberto; Maciel, Fabio Everton; Cruz, Bruno Pinto; Filgueira, Daza de Moraes Vaz Batista; Ferreira, Gabrielle de Jesus; Nery, Luiz Eduardo Maia; Allodi, Silvana

2010-04-01

Crustaceans are interesting models to study the effects of ultraviolet (UV) radiation, and many species may be used as biomarkers for aquatic contamination of UV radiation reaching the surface of the Earth. Here, we investigated cell damage in the visual system of crabs Neohelice granulata that were acclimated to either 12L:12D, constant light, or constant dark, and were exposed to UVA or UVB at 12:00h (noon). The production of reactive oxygen species (ROS), antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (LPO) damage, catalase activity, and pigment dispersion in the eye were evaluated. No significant differences from the three groups of controls (animals acclimated to 12L:12D, or in constant light, or not exposed to UV radiation) were observed in animals acclimated to 12L:12D, however, crabs acclimated to constant light and exposed to UV radiation for 30min showed a significant increase in ROS concentration, catalase activity, and LPO damage, but a decrease in ACAP compared with the controls. Crabs acclimated to constant darkness and exposed to UV for 30min showed a significantly increased ROS concentration and LPO damage, but the ACAP and catalase activity did not differ from the controls (animals kept in the dark while the experimental group was being exposed to UV radiation). Pigment dispersion in the pigment cells of eyes of animals acclimated to constant light was also observed. The results indicate that UVA and UVB alter specific oxidative parameters; however, the cell damage is more evident in animals deviated from the normal dark/light rhythm.

VE-821, an ATR inhibitor, causes radiosensitization in human tumor cells irradiated with high LET radiation.

PubMed

Fujisawa, Hiroshi; Nakajima, Nakako Izumi; Sunada, Shigeaki; Lee, Younghyun; Hirakawa, Hirokazu; Yajima, Hirohiko; Fujimori, Akira; Uesaka, Mitsuru; Okayasu, Ryuichi

2015-08-19

High linear energy transfer (LET) radiation such as carbon ion particles is successfully used for treatment of solid tumors. The reason why high LET radiation accomplishes greater tumor-killing than X-rays is still not completely understood. One factor would be the clustered or complex-type DNA damages. We previously reported that complex DNA double-strand breaks produced by high LET radiation enhanced DNA end resection, and this could lead to higher kinase activity of ATR protein recruited to RPA-coated single-stranded DNA. Although the effect of ATR inhibition on cells exposed to low LET gamma-rays has recently been reported, little is known regarding the effect of ATR inhibitor on cells treated with high LET radiation. The purpose of this study is to investigate the effects of the ATR inhibitor VE-821 in human tumor and normal cells irradiated with high LET carbon ions. HeLa, U2OS, and 1BR-hTERT (normal) cells were pre-treated with 1 μM VE-821 for 1 hour and irradiated with either high LET carbon ions or X-rays. Cell survival, cell cycle distribution, cell growth, and micronuclei formation were evaluated. VE-821 caused abrogation of G2/M checkpoint and forced irradiated cells to divide into daughter cells. We also found that carbon ions caused a higher number of multiple micronuclei than X-rays, leading to decreased cell survival in tumor cells when treated with VE-821, while the survival of irradiated normal cells were not significantly affected by this inhibitor. ATR inhibitor would be an effective tumor radiosensitizer with carbon ion irradiation.

Investigation into the role of phosphatidylserine in modifying the susceptibility of human lymphocytes to secretory phospholipase A(2) using cells deficient in the expression of scramblase.

PubMed

Nelson, Jennifer; Francom, Lyndee L; Anderson, Lynn; Damm, Kelly; Baker, Ryan; Chen, Joseph; Franklin, Sarah; Hamaker, Amy; Izidoro, Izadora; Moss, Eric; Orton, Mikayla; Stevens, Evan; Yeung, Celestine; Judd, Allan M; Bell, John D

2012-05-01

Normal human lymphocytes resisted the hydrolytic action of secretory phospholipase A(2) but became susceptible to the enzyme following treatment with a calcium ionophore, ionomycin. To test the hypothesis that this susceptibility requires exposure of the anionic lipid phosphatidylserine on the external face of the cell membrane, experiments were repeated with a human Burkitt's lymphoma cell line (Raji cells). In contrast to normal lymphocytes or S49 mouse lymphoma cells, most of the Raji cells (83%) did not translocate phosphatidylserine to the cell surface upon treatment with ionomycin. Those few that did display exposed phosphatidylserine were hydrolyzed immediately upon addition of phospholipase A(2). Interestingly, the remaining cells were also completely susceptible to the enzyme but were hydrolyzed at a slower rate and after a latency of about 100s. In contradistinction to the defect in phosphatidylserine translocation, Raji cells did display other physical membrane changes upon ionomycin treatment that may be relevant to hydrolysis by phospholipase A(2). These changes were detected by merocyanine 540 and trimethylammonium diphenylhexatriene fluorescence and were common among normal lymphocytes, S49 cells, and Raji cells. The levels of these latter effects corresponded well with the relative rates of hydrolysis among the three cell lines. These results suggested that while phosphatidylserine enhances the rate of cell membrane hydrolysis by secretory phospholipase A(2), it is not an absolute requirement. Other physical properties such as membrane order contribute to the level of membrane susceptibility to the enzyme independent of phosphatidylserine. Copyright © 2012 Elsevier B.V. All rights reserved.

Oligodendrocyte progenitor cell (OPC) transplantation is unlikely to offer a means of preventing X-irradiation induced damage in the CNS.

PubMed

Chari, Divya M; Gilson, Jennifer M; Franklin, Robin J M; Blakemore, William F

2006-03-01

Oligodendrocyte lineage cells [oligodendrocytes and their parent cells, the oligodendrocyte progenitor cells (OPCs)] are depleted by X-irradiation and progenitor cell transplantation has been proposed as a therapeutic strategy to counteract radiation induced myelopathy. Previous studies have demonstrated that oligodendrocyte progenitor cell (OPC) depletion is a prerequisite for establishing transplanted OPCs in normal tissue. One can therefore predict that the extent and timing of OPC depletion and regeneration following X-irradiation will be crucial factors in determining the feasibility of this therapeutic approach. To address this issue, we have examined the time course of OPC depletion and regeneration following a range of X-irradiation doses (5 to 40 Gy), and its relationship to establishing transplanted OPCs in X-irradiated tissue. Doses above 10 Gy resulted in rapid death of OPCs. With doses up to 20 Gy, surviving X-irradiated OPCs were capable of robust regeneration, restoring normal densities within 6 weeks. Transplanted OPCs could only be established in tissue that had been exposed to > or =20 Gy. Since 20 Gy is close to the ED50 for radiation necrosis, our findings demonstrate the limitation of OPC replacement strategies.

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

Utell, M.J.; Frampton, M.W.; Roberts, N.J.

The studies evaluated short-term respiratory effects of NO2 and identified markers of its toxicity during exposures designed to approximate realistic conditions. Bronchoalveolar lavage (BAL) was used to evaluate effects induced in the airways and air spaces. Exposure protocols were designed to assess the duration of NO2 induced effects and to determine exposure-response relationships. Groups of normal, nonsmoking volunteers of both sexes between the ages of 18 and 40 years old were screened to select subjects that did not exhibit excessive airway reactivity to a carbachol, a drug that causes airways to constrict. Subjects were exposed to nitrogen dioxide or airmore » for three hours. Pulmonary function was measured during and after exposure, and airway reactivity to carbachol was assessed before and after exposure. Lavaged cells were examined for their capacity to inactivate influenza virus and secrete IL-1 in vitro. Cell-free lavage fluid was analyzed for total protein, albumin, alpha 2-macroglobulin, arylsulfatase, and alpha 1-protease inhibitor. In Phase 1 of the study, 15 subjects were exposed to a background concentration of 0.05 parts per million (ppm) NO2 with three 15-minute peaks of 2.0 ppm, and then underwent BAL 3.5 hours after exposure. During Phase 2, eight subjects were exposed to 0.60 ppm NO2 and underwent BAL 18 hours later. In Phase 3, 15 subjects were exposed to 1.5 ppm NO2 and underwent BAL 3.5 hours later. No significant symptomatic or pulmonary function changes were detected in response to any of the NO2 exposures. However, a small but significant increase in airway reactivity was observed after exposure to 1.5 ppm NO2. No symptoms were induced in any of the groups by the carbachol exposures. Analyses of cells recovered by BAL during all three phases revealed no differences in total cell recovery, cell viability, or differential cell counts.« less

Amniotic fluid stem cells rescue both in vitro and in vivo growth, innervation, and motility in nitrofen-exposed hypoplastic rat lungs through paracrine effects.

PubMed

Pederiva, F; Ghionzoli, M; Pierro, A; De Coppi, P; Tovar, J A

2013-01-01

Lung hypoplasia can be prevented in vitro by retinoic acid (RA). Recent evidence suggests that amniotic fluid stem (AFS) cells may integrate injured lungs and influence their recovery. We tested the hypothesis that AFS cells might improve lung growth and motility by paracrine mechanisms. Pregnant rats received either nitrofen or vehicle on E9.5. In vitro E13 embryonic lungs were cultured in the presence of culture medium alone or with RA, basophils, or AFS cells. In vivo green fluorescent protein-expressing (GFP(+)) rat AFS cells were transplanted in nitrofen-exposed rats on E10.5. E13 lung explants were cultured before analysis. The surface, the number of terminal buds, and the frequency of bronchial contractions were assessed. Protein gene product 9.5 (PGP 9.5) and α-actin protein levels were measured. The lung explants transplanted with AFS cells were stained for α-actin, PGP 9.5, and TTF-1. The levels of FGF-10, VEGFα, and TGF-β1 secreted by the AFS cells in the culture medium were measured. Comparison between groups was made by ANOVA. In vitro, the surface, the number of terminal buds, and the bronchial peristalsis were increased in nitrofen+AFS cell explants in comparison with nitrofen-exposed lungs. While nitrofen+RA lungs were similar to nitrofen+AFS ones, basophils did not normalize these measurements. PGP 9.5 protein was decreased in nitrofen lungs, but after adding AFS cells, the value was similar to controls. No differences were found in the expression of α-actin. In vivo, the surface, number of terminal buds, and peristalsis were similar to control after injection of AFS cells in nitrofen-exposed rats. Colocalization with TTF-1-positive cells was found. The levels of FGF-10 and VEGFα were increased in nitrofen+AFS cell explants, while the levels of TGF-β1 were similar to controls. Lung growth, bronchial motility, and innervation were decreased in nitrofen explants and rescued by AFS cells both in vitro and in vivo, similarly to that observed before with RA. The AFS cell beneficial effect was probably related to paracrine action of growth factor secretion.

Comparison of patient-derived high and low phosphatidylserine-exposing colorectal carcinoma cells in their interaction with anti-cancer peptides.

PubMed

Wilms, Dominik; Andrä, Jörg

2017-01-01

Current cancer treatment is frequently compromised by severe adverse effects on healthy cells and tissues as well as by the increasing burden of (multi-)drug resistances. Some representatives of small, amphipathic peptides known as host defense peptides possess the potential to overcome these limitations and to evolve as future anti-cancer therapeutics. Peptide NK-2, derived from porcine NK-lysin, was originally discovered due to its broad-spectrum antimicrobial activities. Today, also potent anti-cancer activity is proven and accompanied by low toxicity towards normal human cells. The molecular basis underlying this target selectivity remains rather elusive. Nevertheless, it is presumptive that preferential peptide interactions with surface factors non-abundant on healthy human cells play a key role. Here, we investigated the cytotoxicity of peptide NK-2 and structurally improved anti-cancer variants thereof against two patient-derived colorectal cancer cell lines, exposing high and low levels of phosphatidylserine on their cell surfaces, respectively. Concluding from a range of in vitro tests involving cellular as well as lipid vesicle-based methods, it is proposed that the magnitude of the accessible membrane surface charge is not a primarily decisive factor for selective peptide interactions. Instead, it is suggested that the level of membrane surface-exposed phosphatidylserine is of crucial importance for the activity of peptide NK-2 and enhanced variants thereof in terms of their cancer cell selectivity, the overall efficacy, as well as the underlying mode of action and kinetics. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Erythroid colony induction without erythropoietin by Friend leukemia virus in vitro.

PubMed

Clarke, B J; Axelrad, A A; Shreeve, M M; McLeod, D L

1975-09-01

Erythroid colonies could be produced without the addition of erythropeietin in plasma cultures seeded with bone marrow cells from normal C3Hf/Bi mice by exposure of the cells in vitro to medium from a cell line (IS) that continuously produces Friend leukemia virus in culture. The activity in the culture medium was viral rather than erythropoietin-like, since it was sedimentable by high-speed centrifugation and heat labile. Erythroid colonies did not develop when the bone marrow cells exposed to virus-containing medium were from mice genetically resistant to Friend virus. IS culture medium contained both Friend spleen focus-forming and XC-plaque-forming activities. No erythroid colonies were induced when genetically sensitive cells were exposed to a preparation from which the spleen focus-forming activity had been removed, but which contained XC plaque-forming activity in high concentration. Thus the spleen focus-forming component of Friend virus appeared to be responsible for inducing erythroid colony formation without erythropoietin in vitro. Some erythroid colonies were also found in control cultures to which neither virus nor erythropoietin had been added. Reduction in the concentration of fetal calf serum in the culture medium substantially decreased the number of these colonies but had only a minor effect on the number of virus-induced colonies. The number of erythroid colonies produced after 2 days of culture without erythropoietin or fetal calf serum was approximately proportional to the titer of Friend spleen focus-forming virus to whcih the bone marrow cells had been exposed. This system should prove useful for investigation in vitro of Friend virus--host cell interactions which lead to erythropoietin-independent erythropoiesis.

Evaluation of the antioxidant effects of melatonin on the larynx mucosa of rats exposed to environmental tobacco smoke.

PubMed

Donmez, Z; Yigit, Ö; Bilici, S; Dursun, N; Gul, M; Dastan, S D; Uzun, H

2016-06-01

This study's aim was to investigate the effect of melatonin in terms of mitigating the effects of smoking on the laryngeal mucosa of rats exposed to environmental tobacco smoke. Rats were divided into four groups: Melatonin + Smoking group exposed to smoke with melatonin; Smoking group exposed to smoke without melatonin; Saline group not exposed to smoke without melatonin; Melatonin group not exposed to smoke with melatonin. CuZn-superoxide dismutase (CuZn-SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were evaluated in plasma and tissues. Tissues were also examined the changes of squamous hyperplasia, keratosis, parakeratosis and epithelial hyperplasia by light microscope and the ultrastructural changes by electron microscope. Tissue SOD, CAT and GSH-Px activities were significantly higher in Saline and Melatonin groups than Melatonin + Smoking and Smoking groups. Plasma CuZn-SOD and CAT activities were significantly higher in Saline and Melatonin groups than Smoking group. Plasma GSH-Px showed no significant difference. The rate of epithelial hyperplasia was significantly higher in Smoking group than the other groups. The rate of parakeratosis was significantly higher in Smoking group than the other groups. The epithelial cells in Melatonin + Smoking group displayed, normal cell structure similar to those in Saline group under electron microscope. The study shows that smoking induces substantial pathological changes in the laryngeal mucosa and melatonin may have some beneficial effects in partially reversing smoking-induced laryngeal injury by inducing the expression of antioxidants; biochemical and histological outcomes also support these findings due to preventing tissue damage in laryngeal mucosa exposed to smoke. © 2015 John Wiley & Sons Ltd.

Radioprotective effects of delphinidin on normal human lung cells against proton beam exposure

PubMed Central

Kim, Hyun Mi; Kim, Suk Hee

2018-01-01

BACKGROUND/OBJECTIVES Exposure of the normal lung tissue around the cancerous tumor during radiotherapy causes serious side effects such as pneumonitis and pulmonary fibrosis. Radioprotectors used during cancer radiotherapy could protect the patient from side effects induced by radiation injury of the normal tissue. Delphinidin has strong antioxidant properties, and it works as the driving force of a radioprotective effect by scavenging radiation-induced reactive oxygen species (ROS). However, no studies have been conducted on the radioprotective effect of delphinidin against high linear energy transfer radiation. Therefore, this study was undertaken to evaluate the radioprotective effects of delphinidin on human lung cells against a proton beam. MATERIALS/METHODS Normal human lung cells (HEL 299 cells) were used for in vitro experiments. The 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay assessed the cytotoxicity of delphinidin and cell viability. The expression of radiation induced cellular ROS was measured by the 2′-7′-dicholordihydrofluorescein diacetate assay. Superoxide dismutase activity assay and catalase activity assay were used for evaluating the activity of corresponding enzymes. In addition, radioprotective effects on DNA damage-induced cellular apoptosis were evaluated by Western blot assay. RESULTS Experimental analysis, including cell survival assay, MTT assay, and Western blot assay, revealed the radioprotective effects of delphinidin. These include restoring the activities of antioxidant enzymes of damaged cells, increase in the levels of pro-survival protein, and decrease of pro-apoptosis proteins. The results from different experiments were compatible with each to provide a substantial conclusion. CONCLUSION Low concentration (2.5 µM/mL) of delphinidin administration prior to radiation exposure was radioprotective against a low dose of proton beam exposure. Hence, delphinidin is a promising shielding agent against radiation, protecting the normal tissues around a cancerous tumor, which are unintentionally exposed to low doses of radiation during proton therapy. PMID:29399295

14 CFR 27.1316 - Electrical and electronic system lightning protection.

Code of Federal Regulations, 2013 CFR

2013-01-01

... after the time the rotorcraft is exposed to lightning; and (2) The system automatically recovers normal operation of that function in a timely manner after the rotorcraft is exposed to lightning. (b) For... recovers normal operation in a timely manner after the rotorcraft is exposed to lightning. [Doc. No. FAA...

14 CFR 27.1316 - Electrical and electronic system lightning protection.

Code of Federal Regulations, 2014 CFR

2014-01-01

... after the time the rotorcraft is exposed to lightning; and (2) The system automatically recovers normal operation of that function in a timely manner after the rotorcraft is exposed to lightning. (b) For... recovers normal operation in a timely manner after the rotorcraft is exposed to lightning. [Doc. No. FAA...

14 CFR 27.1316 - Electrical and electronic system lightning protection.

Code of Federal Regulations, 2012 CFR

2012-01-01

... after the time the rotorcraft is exposed to lightning; and (2) The system automatically recovers normal operation of that function in a timely manner after the rotorcraft is exposed to lightning. (b) For... recovers normal operation in a timely manner after the rotorcraft is exposed to lightning. [Doc. No. FAA...

Mechanism of intracellular signal transduction during injury of renal tubular cells induced by postasphyxial serum in neonates with asphyxia.

PubMed

Zhao, Jin; Dong, Wen-Bin; Li, Peng-yun; Deng, Chun-liang

2009-01-01

Renal injury is a severe and extremely common complication that occurs early in neonates with asphyxia. Reperfusion injury has been suggested as the cause of kidney damage during resuscitation of neonatal asphyxia. Previous studies have demonstrated that postasphyxial serum from neonates with asphyxia may result in apoptosis of renal tubular cells. However, the mechanisms that mediate renal tubular cell apoptosis induced by postasphyxial serum remain poorly understood. In this report we investigate the intracellular signal transduction mechanisms that operate during injury of renal tubular cells induced by postasphyxial serum in neonates. Cultured human renal proximal tubular cells HK-2 cell were exposed to 10% fetal calf serum (normal control), 20% postasphyxial serum or 20% postasphyxial serum with pyrrolidine dithiocarbamate (PDTC). The expression of both BAD and BAX in the cytoplasm was detected by immunohistochemistry. The mitochondria membrane potential (Deltapsim) was examined by confocal microscopy, and the release of the apoptogenic mitochondrial proteins cytochrome C and AIF was assessed by Western blot analysis. Loss of mitochondria membrane potential was detected in HK-2 cells treated with 20% postasphyxial serum as compared to cells in normal serum or PTDC-pretreated cells in 20% postasphyxial serum. A significant increase of Bad and Bax protein expression was also detected, along with the release of cytochrome C and AIF from mitochondria to cytosol in the postasphyxial serum treated cells, but not in the normal or PTDC-pretreated control cells. Our findings suggest that postasphyxial serum may induce renal tubular cell apoptosis through the mitochondrial pathway, and its intracellular signal transduction mechanism includes the activation of nuclear factor-kappaB. Copyright 2009 S. Karger AG, Basel.

Acquired Elastotic Hemangioma: Case Series and Comprehensive Literature Review

PubMed Central

Hinds, Brian R

2017-01-01

Background Acquired elastotic hemangioma is a benign vascular proliferation that typically presents as an asymptomatic red plaque on a sun-exposed site of an adult. Material and Methods The PubMed database was used to search the following words: acquired, angioma, arm, basal, carcinoma, cell, elastosis, elastotic, exposed, forearm, hemangioma, solar, sun, and vascular. The relevant papers and reference cited generated by the search were reviewed. The features from a case series of 11 patients with acquired elastotic hemangioma are presented. In addition, a comprehensive review of the characteristics of this unique hemangioma—not only in our 11 patients but also in the previously reported 34 individuals with this lesion—is provided. Results Acquired elastotic hemangioma, reported in 45 patients (24 women and 21 men), typically appeared as an asymptomatic solitary red plaque in sun-exposed areas—most commonly the forearm--of adults aged 50 years or older. The pathology shows a proliferation of vascular channels—surrounded and intertwined by intense solar elastosis--in the upper dermis, located parallel to the overlying epidermis, and separated from it by a zone of normal-appearing superficial papillary dermis. There was extensive solar elastosis surrounding and between the new blood vessels; some of the endothelial cells protrude (in a hob-nail pattern) into the vessel lumen. The clinical differential diagnosis includes basal cell carcinoma and the pathologic differential diagnosis includes other benign, malignant, and reactive vascular lesions. Ultraviolet radiation may contribute to the pathogenesis of this hemangioma since it occurs on sun-exposed sites. There was no recurrence of the lesion following either excision or observation. Conclusions The possibility of acquired elastotic hemangioma should be considered by clinicians when they encounter an older individual with a new red plaque on a sun-exposed site that clinically appears to be a superficial basal cell carcinoma. PMID:29507844

Impact assessment of repeated exposure of organotypic 3D bronchial and nasal tissue culture models to whole cigarette smoke.

PubMed

Kuehn, Diana; Majeed, Shoaib; Guedj, Emmanuel; Dulize, Remi; Baumer, Karine; Iskandar, Anita; Boue, Stephanie; Martin, Florian; Kostadinova, Radina; Mathis, Carole; Ivanov, Nikolai V; Frentzel, Stefan; Hoeng, Julia; Peitsch, Manuel C

2015-02-12

Cigarette smoke (CS) has a major impact on lung biology and may result in the development of lung diseases such as chronic obstructive pulmonary disease or lung cancer. To understand the underlying mechanisms of disease development, it would be important to examine the impact of CS exposure directly on lung tissues. However, this approach is difficult to implement in epidemiological studies because lung tissue sampling is complex and invasive. Alternatively, tissue culture models can facilitate the assessment of exposure impacts on the lung tissue. Submerged 2D cell cultures, such as normal human bronchial epithelial (NHBE) cell cultures, have traditionally been used for this purpose. However, they cannot be exposed directly to smoke in a similar manner to the in vivo exposure situation. Recently developed 3D tissue culture models better reflect the in vivo situation because they can be cultured at the air-liquid interface (ALI). Their basal sides are immersed in the culture medium; whereas, their apical sides are exposed to air. Moreover, organotypic tissue cultures that contain different type of cells, better represent the physiology of the tissue in vivo. In this work, the utilization of an in vitro exposure system to expose human organotypic bronchial and nasal tissue models to mainstream CS is demonstrated. Ciliary beating frequency and the activity of cytochrome P450s (CYP) 1A1/1B1 were measured to assess functional impacts of CS on the tissues. Furthermore, to examine CS-induced alterations at the molecular level, gene expression profiles were generated from the tissues following exposure. A slight increase in CYP1A1/1B1 activity was observed in CS-exposed tissues compared with air-exposed tissues. A network-and transcriptomics-based systems biology approach was sufficiently robust to demonstrate CS-induced alterations of xenobiotic metabolism that were similar to those observed in the bronchial and nasal epithelial cells obtained from smokers.

Povidone-Iodine Has a Profound Effect on In Vitro Osteoblast Proliferation and Metabolic Function and Inhibits Their Ability to Mineralize and Form Bone.

PubMed

Newton Ede, Matthew P; Philp, Ashleigh M; Philp, Andrew; Richardson, Stephen M; Mohammad, Saeed; Jones, Simon W

2016-05-01

A study examining the clinical protocol of scoliosis wound irrigation, demonstrating povidone-iodine's (PVI) effect on human osteoblast cells. Primary and immortal cell line osteoblasts were treated with 0.35% PVI for 3 minutes, and analyzed for proliferation rate, oxidative capacity, and mineralization. To model spinal wound irrigation with dilute PVI in vitro, in order to investigate the effect of PVI on osteoblast proliferation, metabolism, and bone mineralization. Previously PVI irrigation has been proposed as a safe and effective practice to avoid bacterial growth after spinal surgery. However, recent evidence in multiple cell types suggests that PVI has a deleterious effect on cellular viability and cellular function. Primary and immortal human osteoblast cells were exposed to either phosphate buffered saline control or with 0.35% PVI for 3 minutes. Cellular proliferation was measured over the duration of 7 days by MTS assay. Oxygen consumption rate, extracellular acidification rate, and proton production rate were analyzed using a Seahorse XF24 Bioanalyzer. Protein expression of the electron transport chain subunits CII-SDHB, CIII-UQRCR2, and CV-ATP5A was measured via Western blotting. Mineralized bone nodules were stained with alizarin red. Expressed as a percentage of normal osteoblast proliferation, osteoblasts exposed to 0.35% PVI exhibited a significant 24% decrease in proliferation after 24 hours. This was a sustained response, resulting in a 72% decline in cellular proliferation at 1 week. There was a significant reduction in oxygen consumption rate, extracellular acidification rate, and proton production rate (P < 0.05), in osteoblasts that had been exposed to 0.35% PVI for 3 minutes, coupled with a marked reduction in the protein expression of CII-SDHB. Osteoblasts exposed to 0.35% PVI exhibited reduced bone nodule mineralization compared to control phosphate buffered saline exposed osteoblasts (P < 0.01). PVI has a rapid and detrimental effect on human osteoblast cellular proliferation, metabolic function, and bone nodule mineralization. NA.

Effect of Short-Term Hypergravity Treatment on Mouse 2-Cell Embryo Development

NASA Astrophysics Data System (ADS)

Ning, Li-Na; Lei, Xiao-Hua; Cao, Yu-Jing; Zhang, Yun-Fang; Cao, Zhong-Hong; Chen, Qi; Duan, En-Kui

2015-11-01

Though there are numerous biological experiments, which have been performed in a space environment, to study the physiological effect of space travel on living organisms, while the potential effect of weightlessness or short-term hypergravity on the reproductive system in most species, particularly in mammalian is still controversial and unclear. In our previous study, we investigated the effect of space microgravity on the development of mouse 4-cell embryos by using Chinese SJ-8. .Unexpectedly, we did not get any developed embryo during the space-flight. Considering that the process of space experiment is quite different from most experiments done on earth in several aspects such as, the vibration and short-term hypergravity during the rock launching and landing. Thus we want to know whether the short-term hypergravity produced by the launch process affect the early embryo development in mice, and howthe early embryos respond to the hypergravity. In present study, we are mimicking the short-term hypergravity during launch by using a centrifuge to investigate its influence on the development of early embryo (2-cell) in mice. We also examined the actin filament distribution in 2-cell embryos by immunostaining to test their potential capacity of development under short-term hypergravity exposure. Our results showed that most 2-cell embryos in the hypergravity exposure groups developed into blastocysts with normal morphology after 72h cultured in vitro, and there is no obvious difference in the development rate of blastocyst formation compared to the control. Moreover, there were no statistically significant differences in birth rates after oviduct transfer of 2-cell mouse embryos exposed on short-term hypergravity compared with 1 g condition. In addition, the well-organized actin distribution appeared in 2-cell embryos after exposed on hypergravity and also in the subsequent developmental blastocysts. Taken together, our data shows that short-term exposure in hypergravity conditions does not affect the normal development and actin filament structures of mouse embryos.

Designing Trojan Horses | Center for Cancer Research

Cancer.gov

Waging battle against cancer cells without inflicting damage on normal tissue has long been a goal for cancer treatment. A new type of drug called immunotoxins may help make this goal a reality. Much like the Greeks used a wooden horse to get soldiers inside the gates of Troy, immunotoxins use clever genetic engineering to get a lethal toxin inside cancer cells. Each immunotoxin consists of two components an antibody and a toxin that are fused together. The custom-designed antibody acts as a homing signal, seeking out a specific target present on the surface of cancer cells. When the antibody binds its target, the whole immunotoxin is brought inside the cell. Unwittingly, the cancer cell has exposed itself to a powerful poison, a mistake that will likely condemn it to death.

The mitochondria targeted antioxidant MitoQ protects against fluoroquinolone-induced oxidative stress and mitochondrial membrane damage in human Achilles tendon cells.

PubMed

Lowes, Damon A; Wallace, Carol; Murphy, Michael P; Webster, Nigel R; Galley, Helen F

2009-04-01

Tendinitis and tendon rupture during treatment with fluoroquinolone antibiotics is thought to be mediated via oxidative stress. This study investigated whether ciprofloxacin and moxifloxacin cause oxidative stress and mitochondrial damage in cultured normal human Achilles' tendon cells and whether an antioxidant targeted to mitochondria (MitoQ) would protect against such damage better than a non-mitochondria targeted antioxidant. Human tendon cells from normal Achilles' tendons were exposed to 0-0.3 mM antibiotic for 24 h and 7 days in the presence of 1 microM MitoQ or an untargeted form, idebenone. Both moxifloxacin and ciprofloxacin resulted in up to a 3-fold increase in the rate of oxidation of dichlorodihydrofluorescein, a marker of general oxidative stress in tenocytes (p<0.0001) and loss of mitochondrial membrane permeability (p<0.001). In cells treated with MitoQ the oxidative stress was less and mitochondrial membrane potential was maintained. Mitochondrial damage to tenocytes during fluoroquinolone treatment may be involved in tendinitis and tendon rupture.

Mechanobiology in Lung Epithelial Cells: Measurements, Perturbations, and Responses

PubMed Central

Waters, Christopher M.; Roan, Esra; Navajas, Daniel

2015-01-01

Epithelial cells of the lung are located at the interface between the environment and the organism and serve many important functions including barrier protection, fluid balance, clearance of particulate, initiation of immune responses, mucus and surfactant production, and repair following injury. Because of the complex structure of the lung and its cyclic deformation during the respiratory cycle, epithelial cells are exposed to continuously varying levels of mechanical stresses. While normal lung function is maintained under these conditions, changes in mechanical stresses can have profound effects on the function of epithelial cells and therefore the function of the organ. In this review, we will describe the types of stresses and strains in the lungs, how these are transmitted, and how these may vary in human disease or animal models. Many approaches have been developed to better understand how cells sense and respond to mechanical stresses, and we will discuss these approaches and how they have been used to study lung epithelial cells in culture. Understanding how cells sense and respond to changes in mechanical stresses will contribute to our understanding of the role of lung epithelial cells during normal function and development and how their function may change in diseases such as acute lung injury, asthma, emphysema, and fibrosis. PMID:23728969

Cationic peptide exposure enhances pulsed-electric-field-mediated membrane disruption.

PubMed

Kennedy, Stephen M; Aiken, Erik J; Beres, Kaytlyn A; Hahn, Adam R; Kamin, Samantha J; Hagness, Susan C; Booske, John H; Murphy, William L

2014-01-01

The use of pulsed electric fields (PEFs) to irreversibly electroporate cells is a promising approach for destroying undesirable cells. This approach may gain enhanced applicability if the intensity of the PEF required to electrically disrupt cell membranes can be reduced via exposure to a molecular deliverable. This will be particularly impactful if that reduced PEF minimally influences cells that are not exposed to the deliverable. We hypothesized that the introduction of charged molecules to the cell surfaces would create regions of enhanced transmembrane electric potential in the vicinity of each charged molecule, thereby lowering the PEF intensity required to disrupt the plasma membranes. This study will therefore examine if exposure to cationic peptides can enhance a PEF's ability to disrupt plasma membranes. We exposed leukemia cells to 40 μs PEFs in media containing varying concentrations of a cationic peptide, polyarginine. We observed the internalization of a membrane integrity indicator, propidium iodide (PI), in real time. Based on an individual cell's PI fluorescence versus time signature, we were able to determine the relative degree of membrane disruption. When using 1-2 kV/cm, exposure to >50 μg/ml of polyarginine resulted in immediate and high levels of PI uptake, indicating severe membrane disruption, whereas in the absence of peptide, cells predominantly exhibited signatures indicative of no membrane disruption. Additionally, PI entered cells through the anode-facing membrane when exposed to cationic peptide, which was theoretically expected. Exposure to cationic peptides reduced the PEF intensity required to induce rapid and irreversible membrane disruption. Critically, peptide exposure reduced the PEF intensities required to elicit irreversible membrane disruption at normally sub-electroporation intensities. We believe that these cationic peptides, when coupled with current advancements in cell targeting techniques will be useful tools in applications where targeted destruction of unwanted cell populations is desired.

Increased viability of odontoblast-like cells subjected to low-level laser irradiation

NASA Astrophysics Data System (ADS)

Oliveira, C. F.; Basso, F. G.; Lins, E. C.; Kurachi, C.; Hebling, J.; Bagnato, V. S.; de Souza Costa, C. A.

2010-07-01

Studies have shown that the increase of cell metabolism depends on the low level laser therapy (LLLT) parameters used to irradiate the cells. However, the optimal laser dose to up-regulate pulp cell activity remains unknown. Consequently, the aim of this study was to evaluate the metabolic response of odontoblast-like cells (MDPC-23) exposed to different LLLT doses. Cells at 20000 cells/cm2 were seeded in 24-well plates using plain culture medium (DMEM) and were incubated in a humidified incubator with 5% CO2 at 37°C. After 24 h, the culture medium was replaced by fresh DMEM supplemented with 5% (stress by nutritional deficit) or 10% fetal bovine serum (FBS). The cells were exposed to different laser doses from a near infrared diode laser prototype designed to provide a uniform irradiation of the wells. The experimental groups were: G1: 1.5 J/cm2 + 5% FBS; G2: 1.5 J/cm2 + 10% FBS; G3: 5 J/cm2 + 5% FBS; G4: 5 J/cm2 + 10% FBS; G5: 19 J/cm2 + 5% FBS; G6: 19 J/cm2 + 10% FBS. LLLT was performed in 3 consecutive irradiation cycles with a 24-hour interval. Non-irradiated cells cultured in DMEM supplemented with either 5 or 10% FBS served as control groups. The analysis of the metabolic response was performed by the MTT assay 3 h after the last irradiation. G1 presented an increase in SDH enzyme activity and differed significantly (Mann-Whitney test, p < 0.05) from the other groups. Analysis by scanning electron microscopy showed normal cell morphology in all groups. Under the tested conditions, LLLT stimulated the metabolic activity of MDPC-23 cultured in DMEM supplemented with 5% FBS and exposed to a laser dose of 1.5 J/cm2. These findings are relevant for further studies on the action of near infrared lasers on cells with odontoblast phenotype.

Effects of ozone in normal human epidermal keratinocytes.

PubMed

McCarthy, James T; Pelle, Edward; Dong, Kelly; Brahmbhatt, Krupa; Yarosh, Dan; Pernodet, Nadine

2013-05-01

Ozone is a tropospheric pollutant that can form at ground level as a result of an interaction between sunlight and hydrocarbon engine emissions. As ozone is an extremely oxidative reaction product, epidermal cells are in the outer layer of defense against ozone. We exposed normal human epidermal keratinocytes (NHEK) to concentrations of ozone that have been measured in cities and assayed for its effects. Hydrogen peroxide and IL-1α levels both increased while ATP levels decreased. We found a decrease in the NAD-dependent histone deacetylase, sirtuin 3. Lastly, we found that ozone increased DNA damage as evaluated by Comet assay. Taken together, our results show increased damage to NHEK that will ultimately impair normal cellular function as a result of an environmentally relevant ozone exposure. © 2013 John Wiley & Sons A/S.

Irradiation at 636 nm positively affects diabetic wounded and hypoxic cells in vitro.

PubMed

Sekhejane, Palesa R; Houreld, Nicolette N; Abrahamse, Heidi

2011-08-01

This study investigated the effect of low-intensity laser irradiation (LILI) on pro-inflammatory cytokines involved in wound healing processes in diabetes and hypoxia. Diabetes is associated with impaired wound healing and a prolonged inflammatory phase. Pro-inflammatory cytokines such as interleukin (IL)-1β, tumor necrosis factor (TNF)-α and IL-6 are elevated in diabetes. LILI has been reported to accelerate wound healing and decrease inflammatory cytokines. A human skin fibroblast cell line (WS1) was used in vitro. Cells were exposed to various insults, namely, wounding, and a diabetic or hypoxic environment. Experimental cells were exposed to an energy density of 5  J/cm(2) using a continuous wave 636-nm diode laser at an average power of 95  mW, an illuminated area of 9.05  cm(2), and an irradiance of 11 mW/cm(2) (irradiation time, 476  sec). The effect of laser irradiation on cytokine expression was examined at 1 or 24  h post-irradiation. Cellular morphology, viability, proliferation, and cytokine expression (IL-1β, IL-6, and TNF-α) were investigated. Translocation of nuclear factor-kappa B (NF-κB) was also determined. There was a higher rate of migration in irradiated wounded cultures, and irradiated hypoxic cells showed an improvement in cellular morphology. All cell models showed an increase in proliferation. Normal wounded cells showed a decrease in apoptosis, TNF-α, and IL-1β. Diabetic wounded cells showed an increase in viability and a decrease in apoptosis and IL-1β, whereas hypoxic cells showed an increase in viability and IL-6, and a decrease in apoptosis and TNF-α. NF-κB was translocated into the nucleus post-irradiation. Phototherapy resulted in hastened wound closure, increased proliferation, and normalization of cellular function. The decrease in the different pro-inflammatory cytokines and NF-κB translocation was model and time dependent. Overall, laser irradiation resulted in a reduction in inflammatory cytokines and directed cells into the cell survival pathway.

An intracellular protein that binds amyloid-β peptide and mediates neurotoxicity in Alzheimer's disease

NASA Astrophysics Data System (ADS)

Du Yan, Shi; Fu, Jin; Soto, Claudio; Chen, Xi; Zhu, Huaijie; Al-Mohanna, Futwan; Collison, Kate; Zhu, Aiping; Stern, Eric; Saido, Takaomi; Tohyama, Masaya; Ogawa, Satoshi; Roher, Alex; Stern, David

1997-10-01

Amyloid-β is a neurotoxic peptide which is implicated in the pathogenesis of Alzheimer's disease. It binds an intracellular polypeptide known as ERAB, thought to be a hydroxysteroid dehydrogenase enzyme, which is expressed in normal tissues, but is overexpressed in neurons affected in Alzheimer's disease. ERAB immunoprecipitates with amyloid-β, and when cell cultures are exposed to amyloid-β, ERAB inside the cell is rapidly redistributed to the plasma membrane. The toxic effect of amyloid-β on these cells is prevented by blocking ERAB and is enhanced by overexpression of ERAB. By interacting with intracellular amyloid-β, ERAB may therefore contribute to the neuronal dysfunction associated with Alzheimer's disease.

Ultrastructural changes in tracheal epithelial cells exposed to oxygen

NASA Technical Reports Server (NTRS)

Philpott, D. E.; Harrison, G. A.; Turnbill, C.; Black, S.

1977-01-01

White albino rats were sacrificed after 24, 36, 48, 72, and 96 h of exposure to 100% O2 at 1 atm. Tissue was prepared for the scanning electron microscope (SEM) by Critical Point Drying and for the transmission electron microscope (TEM) by plastic embedding. Scanning microscopy showed a loss of microvilli after 48 h of exposure. Cilia appeared relatively normal with SEM, but TEM revealed changes in the outer membrane. In TEM, nonciliated cells appeared swollen and often encroached on the ciliated cells. A heavy mucous blanket remained even after processing. All the changes observed that are induced by oxygen exposure contribute to mucostasis, reducing and/or halting mucociliary clearance.

Down-regulation of BAX gene during carcinogenesis and acquisition of resistance to 5-FU in colorectal cancer.

PubMed

Manoochehri, Mehdi; Karbasi, Ashraf; Bandehpour, Mojgan; Kazemi, Bahram

2014-04-01

Carcinogenesis and resistance to chemotherapy could be as results of expression variations in apoptosis regulating genes. Changes in the expression of apoptosis interfering genes may contribute to colorectal carcinogenesis and resistance to 5-Flourouracil (5-FU) during treatment schedule period. The present study aimed to evaluate the expression of pro-apoptotic and anti-apoptotic genes in colorectal cancer tumor tissues, normal adjacent tissues, and tumor colorectal cancer cell line during acquiring resistance to 5-FU in HT-29 based on Bolus treatment protocol. The normal and tumor tissues were obtained from hospital after surgery and total RNA was extracted for expression analysis. The HT-29 colorectal cancer cell line was cultured and exposed with 5-FU in three stages based on Bolus protocol. The MTT assay and Real Time PCR were carried out to determine the sensitivity to the drug and expression of desired genes, respectively. The obtained data showed that Proapoptotic genes, BAX and BID, were down-regulated in resistant derivate cells compared to wild type HT-29 cells. On the other hand Antiapoptotic genes, CIAP1 and XIAP, showed upregulation in resistant cells compared to wild type ones. Furthermore, BAX and FAS genes showed down-regulation in tumor samples in comparison to normal adjacent tissues. In conclusion, the results of our study suggest that BAX down-regulation could contribute as an important factor during both colorectal carcinogenesis and cell resistance to 5-FU.

Murine tissues exposed to cytotoxic drugs display altered patterns of Candida albicans adhesion.

PubMed Central

López-Ribot, J L; McVay, C S; Chaffin, W L

1994-01-01

An ex vivo adhesion assay was used to examine the binding of Candida albicans yeast cells to tissues from mice treated with cytotoxic drugs such as lipopolysaccharide and the clinically used anticancer drugs doxorubicin, cisplatin, and vincristine. No major differences were observed in binding of the fungal cells to liver and kidney tissues from treated or untreated animals. All drug-treated spleens displayed altered patterns of C. albicans adhesion compared with the control group, with yeast cells bound not only to the marginal zone but also to the white and red pulp. Immunostaining for macrophages, which are proposed as the site of normal adhesion, showed no apparent differences between the control and the experimental spleens that could account for the change in adhesion patterns. Scanning electron microscopy images suggested that yeast binding to the white pulp of treated tissue is mediated through fibers, perhaps extracellular matrix components exposed as result of the cytotoxic treatment. Exposure of new attachment sites for C. albicans in treated tissues may facilitate initiation of infection. Images PMID:7927678

Surface morphology and morphometry of rat alveolar macrophages after ozone exposure

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

Dormans, J.A.; Rombout, P.J.; van Loveren, H.

1990-09-01

As the ultrastructural data on the effects of ozone on pulmonary alveolar macrophages (PAM) are lacking, transmission (TEM) and scanning (SEM) electron microscopy were performed on rat PAM present in alveolar lavages following exposure to ozone. Rats were continuously exposed for 7 d to ozone concentrations ranging from 0.25 to 1.50 mg/m3 for 7 d followed by a 5-d recovery period. Additionally, morphometry on lung sections was performed to quantitate PAM. In a second experiment rats were continuously exposed to 1.50 mg O3/m3 for 1, 3, 5, or 7 d. To study the influence of concurrent ozone exposure and lungmore » infection, due to Listeria monocytogenes, rats were exposed for 7 d to 1.50 mg O3/m3 after a Listeria infection. The surface area of lavaged control PAM was uniformly covered with ruffles as shown by SEM and TEM. Exposure to 0.5 mg ozone/m3 for 7 d resulted in cells partly covered with microvilli and blebs in addition to normal ruffles. The number of large size PAM increased with an increase in ozone concentration. After 1 d of exposure, normal-appearing as well as many small macrophages with ruffles and scattered lymphocytes were seen. Lavage samples taken after 5 or 7 d of exposure showed an identical cell composition to that taken after 3 d of exposure. After Listeria infection alone, lavage samples consisted of mainly lymphocytes and some macrophages. Small quantitative changes, such as an increase in the number of polymorphonuclear neutrophils and large-size PAM, occurred in lavages after ozone exposure and infection with L. monocytogenes. Morphometric examination of lung sections revealed a concentration-related increase in the number of PAM, even in animals exposed to 0.25 mg ozone/m3 for 7 d. Centriacinar regions were more severely affected than other regions of lung tissue.« less

Detection of early changes in lung cell cytology by flow-systems analysis techniques

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

Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.

1976-12-01

This report summarizes results of continuing experiments to develop cytological and biochemical indicators for estimating damage to respiratory cells in test animals exposed by inhalation to toxic agents associated with nonnuclear energy production, the specific goal being the application of advanced multiparameter flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. Normal Syrian hamster lung cell samples composed of macrophages, leukocytes, ciliated columnar cells, and epithelial cells were stained with fluorescent dyes specific for different biochemical parameters and were analyzed in liquid suspension as they flowed through a chamber intersecting a laser beam of exciting light.more » Multiple sensors measured the total or two-color fluorescence and light scatter on a cell-by-cell basis. Cellular parameters proportional to optical measurements (i.e., cell size, DNA content, total protein, nonspecific esterase activity, nuclear and cytoplasmic diameters) were displayed as frequency distribution histograms. Lung cell samples were also separated according to various cytological parameters and identified microscopically. The basic operating features of the methodology are discussed briefly, along with specific examples of preliminary results illustrating the initial characterization of exfoliated pulmonary cells from normal hamsters. As the flow technology is adapted further to the analysis of respiratory cells, measurements of changes in physical and biochemical properties as a function of exposure to toxic agents will be performed.« less

Cationic Peptide Exposure Enhances Pulsed-Electric-Field-Mediated Membrane Disruption

PubMed Central

Kennedy, Stephen M.; Aiken, Erik J.; Beres, Kaytlyn A.; Hahn, Adam R.; Kamin, Samantha J.; Hagness, Susan C.; Booske, John H.; Murphy, William L.

2014-01-01

Background The use of pulsed electric fields (PEFs) to irreversibly electroporate cells is a promising approach for destroying undesirable cells. This approach may gain enhanced applicability if the intensity of the PEF required to electrically disrupt cell membranes can be reduced via exposure to a molecular deliverable. This will be particularly impactful if that reduced PEF minimally influences cells that are not exposed to the deliverable. We hypothesized that the introduction of charged molecules to the cell surfaces would create regions of enhanced transmembrane electric potential in the vicinity of each charged molecule, thereby lowering the PEF intensity required to disrupt the plasma membranes. This study will therefore examine if exposure to cationic peptides can enhance a PEF’s ability to disrupt plasma membranes. Methodology/Principal Findings We exposed leukemia cells to 40 μs PEFs in media containing varying concentrations of a cationic peptide, polyarginine. We observed the internalization of a membrane integrity indicator, propidium iodide (PI), in real time. Based on an individual cell’s PI fluorescence versus time signature, we were able to determine the relative degree of membrane disruption. When using 1–2 kV/cm, exposure to >50 μg/ml of polyarginine resulted in immediate and high levels of PI uptake, indicating severe membrane disruption, whereas in the absence of peptide, cells predominantly exhibited signatures indicative of no membrane disruption. Additionally, PI entered cells through the anode-facing membrane when exposed to cationic peptide, which was theoretically expected. Conclusions/Significance Exposure to cationic peptides reduced the PEF intensity required to induce rapid and irreversible membrane disruption. Critically, peptide exposure reduced the PEF intensities required to elicit irreversible membrane disruption at normally sub-electroporation intensities. We believe that these cationic peptides, when coupled with current advancements in cell targeting techniques will be useful tools in applications where targeted destruction of unwanted cell populations is desired. PMID:24671150

Neoplastic transformation of SV40-immortalized human urinary tract epithelial cells by in vitro exposure to 3-methylcholanthrene.

PubMed

Reznikoff, C A; Loretz, L J; Christian, B J; Wu, S Q; Meisner, L F

1988-08-01

Normal human urinary tract epithelial cells (HUC) were neoplastically transformed in vitro using a step-wise strategy. First, a partially transformed non-virus-producing cell line was obtained after infection of HUC with simian virus 40 (SV40). This cell line (SV-HUC-1) was demonstrated to be clonal in origin, as 100% of cells contained at least five of seven marker chromosomes. Marker chromosomes were formed by balanced translocations resulting in a 'pseudodiploid' cell line. SV-HUC-1 showed altered growth properties in vitro (e.g. anchorage independent growth) but failed to form tumors in athymic nude mice, even after 3 years in culture (80 passages). In the studies reported here, SV-HUC-1 at early passages (P15-P19) were exposed to 3-methylcholanthrene (MCA) in three separate experiments. After a six-week post-treatment period of cell culture, cells were inoculated s.c. into athymic nude mice. In all experiments, MCA-treated SV-HUC-1 formed carcinomas in mice usually with a latent period of 5-8 weeks. These carcinomas showed heterogeneity with respect to histopathologies and growth properties in the mice and karyotypes. All the tumors retained SV-HUC-1 chromosome markers, but each independent transformant was aneuploid and contained unique new marker chromosomes. Chromosomes usually altered in tumor cells included numbers 3, 5, 6, 9, 11 and 13. Mutations in the ras family of cellular proto-oncogenes resulting in altered mobility of the p21 protein product were not detected in six cell lines established from independently derived tumors. It is not yet known whether other cellular proto-oncogenes are activated in these tumorigenic transformants. Neither control SV-HUC-1 (which were not exposed to MCA), nor early passage HUC exposed to MCA formed tumors when inoculated into mice. Thus, the tumorigenic transformation of HUC resulted from the combined actions of SV40 and MCA.

Semi-quantitative estimation of cellular SiO2 nanoparticles using flow cytometry combined with X-ray fluorescence measurements.

PubMed

Choi, Seo Yeon; Yang, Nuri; Jeon, Soo Kyung; Yoon, Tae Hyun

2014-09-01

In this study, we have demonstrated feasibility of a semi-quantitative approach for the estimation of cellular SiO2 nanoparticles (NPs), which is based on the flow cytometry measurements of their normalized side scattering intensity. In order to improve our understanding on the quantitative aspects of cell-nanoparticle interactions, flow cytometry, transmission electron microscopy, and X-ray fluorescence experiments were carefully performed for the HeLa cells exposed to SiO2 NPs with different core diameters, hydrodynamic sizes, and surface charges. Based on the observed relationships among the experimental data, a semi-quantitative cellular SiO2 NPs estimation method from their normalized side scattering and core diameters was proposed, which can be applied for the determination of cellular SiO2 NPs within their size-dependent linear ranges. © 2014 International Society for Advancement of Cytometry.

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

Li, Wei; Fu, Jianfang; Zhang, Shun

Understanding how chemotherapeutic agents mediate testicular toxicity is crucial in light of compelling evidence that male infertility, one of the severe late side effects of intensive cancer treatment, occurs more often than they are expected to. Previous study demonstrated that bortezomib (BTZ), a 26S proteasome inhibitor used to treat refractory multiple myeloma (MM), exerts deleterious impacts on spermatogenesis in pubertal mice via unknown mechanisms. Here, we showed that intermittent treatment with BTZ resulted in fertility impairment in adult mice, evidenced by testicular atrophy, desquamation of immature germ cells and reduced caudal sperm storage. These deleterious effects may originate from themore » elevated apoptosis in distinct germ cells during the acute phase and the subsequent disruption of Sertoli–germ cell anchoring junctions (AJs) during the late recovery. Mechanistically, balance between AMP-activated protein kinase (AMPK) activation and Akt/ERK pathway appeared to be indispensable for AJ integrity during the late testicular recovery. Of particular interest, the upregulated testicular apoptosis and the following disturbance of Sertoli–germ cell interaction may both stem from the excessive oxidative stress elicited by BTZ exposure. We also provided the in vitro evidence that AMPK-dependent mechanisms counteract follicle-stimulating hormone (FSH) proliferative effects in BTZ-exposed Sertoli cells. Collectively, BTZ appeared to efficiently prevent germ cells from normal development via multiple mechanisms in adult mice. Employment of antioxidants and/or AMPK inhibitor may represent an attractive strategy of fertility preservation in male MM patients exposed to conventional BTZ therapy and warrants further investigation. - Highlights: • Intermittent treatment with BTZ caused fertility impairment in adult mice. • BTZ treatment elicited apoptosis during early phase of testicular recovery. • Up-regulation of oxidative stress by BTZ treatment disrupted AJs dynamics. • BTZ treatment stimulated AMPK activity during late phase of testicular recovery. • AMPK-dependent mechanisms counteract FSH proliferative effects in BTZ-exposed SCs.« less

Propagation Distance of the α-Particle-Induced Bystander Effect: The Role of Nuclear Traversal and Gap Junction Communication

PubMed Central

Gaillard, Sylvain; Pusset, David; de Toledo, Sonia M.; Fromm, Michel; Azzam, Edouard I.

2009-01-01

When cell populations are exposed to low-dose α-particle radiation, a significant fraction of the cells will not be traversed by a radiation track. However, stressful effects occur in both irradiated and bystander cells in the population. Characterizing these effects, and investigating their underlying mechanism(s), is critical to understanding human health risks associated with exposure to α particles. To this end, confluent normal human fibroblast cultures were grown on polyethylene terephthalate foil grafted to an ultrathin solid-state nuclear track detector and exposed under non-perturbing conditions to low-fluence α particles from a broadbeam irradiator. Irradiated and affected bystander cells were localized with micrometer precision. The stress-responsive protein p21Waf1 (also known as CDKN1A) was induced in bystander cells within a 100-µm radius from an irradiated cell. The mean propagation distance ranged from 20 to 40 µm around the intranuclear α-particle impact point, which corresponds to a set of ∼30 cells. Nuclear traversal, induced DNA damage, and gap junction communication were critical contributors to propagation of this stressful effect The strategy described here may be ideal to investigate the size of radiation-affected target and the relative contribution of different cellular organelles to bystander effects induced by energetic particles, which is relevant to radioprotection and cancer radiotherapy. PMID:19580486

Mechanisms of kidney repair by human mesenchymal stromal cells after ischemia: a comprehensive view using label-free MS(E).

PubMed

da Costa, Milene R; Pizzatti, Luciana; Lindoso, Rafael S; Sant'Anna, Julliana Ferreira; DuRocher, Barbara; Abdelhay, Eliana; Vieyra, Adalberto

2014-06-01

Acute kidney injury (AKI) is one of the more frequent and lethal pathological conditions seen in intensive care units. Currently available treatments are not totally effective but stem cell-based therapies are emerging as promising alternatives, especially the use of mesenchymal stromal cells (MSC), although the signaling pathways involved in their beneficial actions are not fully understood. The objective of this study was to identify signaling networks and key proteins involved in the repair of ischemia by MSC. Using an in vitro model of AKI to investigate paracrine interactions and label-free high definition 2D-NanoESI-MS(E) , differentially expressed proteins were identified in a human renal proximal tubule cell lineage (HK-2) exposed to human MSC (hMSC) after an ischemic insult. In silico analysis showed that hMSC stimulated antiapoptotic activity, normal ROS handling, energy production, cytoskeleton organization, protein synthesis, and cell proliferation. The proteomic data were validated by parallel experiments demonstrating reduced apoptosis in HK-2 cells and recovery of intracellular ATP levels. qRT-PCR for proteins implicated in the above processes revealed that hMSC exerted their effects by stimulating translation, not transcription. Western blotting of proteins associated with ROS and energy metabolism confirmed their higher abundance in HK-2 cells exposed to hMSC. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblasts after alpha particle irradiation

NASA Astrophysics Data System (ADS)

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K.

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G2 phase premature chromosome condensation (G2-PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. mFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblast after alpha particle irradiation.

PubMed

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G 2 phase premature chromosome condensation (G 2 -PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. MFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

Metabolic and morphological differences between rapidly proliferating cancerous and normal breast epithelial cells.

PubMed

Meadows, Adam L; Kong, Becky; Berdichevsky, Marina; Roy, Siddhartha; Rosiva, Rosiva; Blanch, Harvey W; Clark, Douglas S

2008-01-01

The metabolic and morphological characteristics of two human epithelial breast cell populations--MCF7 cells, a cancerous cell line, and 48R human mammary epithelial cells (48R HMECs), a noncancerous, finite lifespan cell strain--were compared at identical growth rates. Both cell types were induced to grow rapidly in nutrient-rich media containing 13C-labeled glucose, and the isotopic enrichment of cellular metabolites was quantified to calculate metabolic fluxes in key pathways. Despite their similar growth rates, the cells exhibited distinctly different metabolic and morphological profiles. MCF7 cells have an 80% smaller exposed surface area and contain 26% less protein per cell than the 48R cells. Surprisingly, rapidly proliferating 48R cells exhibited a 225% higher per-cell glucose consumption rate, a 250% higher per-cell lactate production rate, and a nearly identical per-cell glutamine consumption rate relative to the cancer cell line. However, when fluxes were considered on the basis of exposed area, the cancer cells were observed to have higher glucose, lactate, and glutamine fluxes, demonstrating superior transport capabilities per unit area of cell membrane. MCF7 cells also consumed amino acids at rates much higher than are generally required for protein synthesis, whereas 48R cells generally did not. Pentose phosphate pathway activity was higher in MCF7 cells, and the flux of glutamine to glutamate was less reversible. Energy efficiency was significantly higher in MCF7 cells, as a result of a combination of their smaller size and greater reliance on the TCA cycle than the 48R cells. These observations support evolutionary models of cancer cell metabolism and suggest targets for metabolic drugs in metastatic breast cancers.

Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

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

Xu, Bo; Chen, Minjian; Yao, Mengmeng

Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cellmore » cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Furthermore, glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.« less

Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

DOE PAGES

Xu, Bo; Chen, Minjian; Yao, Mengmeng; ...

2015-10-22

Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cellmore » cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Furthermore, glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.« less

A novel platelet activating factor receptor antagonist reduces cell infiltration and expression of inflammatory mediators in mice exposed to desiccating conditions after PRK.

PubMed

Esquenazi, Salomon; He, Jiucheng; Li, Na; Bazan, Nicolas G; Esquenazi, Isi; Bazan, Haydee E P

2009-01-01

To study the contribution of a novel PAF receptor antagonist LAU-0901 in the modulation of the increased inflammatory response in mice exposed to dessicating conditions (DE) after PRK. Eighty 13-14 week old female Balb/C mice were used. They were divided into two groups: One group was treated with LAU-0901 topical drops. The other group was treated with vehicle. In each group ten mice served as controls and ten were placed in DE. The other twenty mice underwent bilateral PRK and were divided in two additional groups: ten mice remained under normal conditions (NC) and the other ten were exposed to DE. After 1 week all animals underwent in vivo confocal microscopy, immunostaining and western blotting analysis. Confocal microscopy showed an increased number of reflective structures in the corneal epithelium after PRK and exposure to DE in eyes treated with vehicle as compared to eyes treated with LAU-090). Significant decrease of COX-2 and Arginase I expression and reduced alpha SMA cells was observed after PRK and exposure to DE in eyes treated with LAU-0901. Exposure of mice to a DE after PRK increases the epithelial turnover rate. PAF is involved in the inflammatory cell infiltration and expression of inflammatory cytokines that follow PRK under DE.

Aspergillus oryzae AoSO is a novel component of stress granules upon heat stress in filamentous fungi.

PubMed

Huang, Hsiang-Ting; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

2013-01-01

Stress granules are a type of cytoplasmic messenger ribonucleoprotein (mRNP) granule formed in response to the inhibition of translation initiation, which typically occurs when cells are exposed to stress. Stress granules are conserved in eukaryotes; however, in filamentous fungi, including Aspergillus oryzae, stress granules have not yet been defined. For this reason, here we investigated the formation and localization of stress granules in A. oryzae cells exposed to various stresses using an EGFP fusion protein of AoPab1, a homolog of Saccharomyces cerevisiae Pab1p, as a stress granule marker. Localization analysis showed that AoPab1 was evenly distributed throughout the cytoplasm under normal growth conditions, and accumulated as cytoplasmic foci mainly at the hyphal tip in response to stress. AoSO, a homolog of Neurospora crassa SO, which is necessary for hyphal fusion, colocalized with stress granules in cells exposed to heat stress. The formation of cytoplasmic foci of AoSO was blocked by treatment with cycloheximide, a known inhibitor of stress granule formation. Deletion of the Aoso gene had effects on the formation and localization of stress granules in response to heat stress. Our results suggest that AoSO is a novel component of stress granules specific to filamentous fungi. The authors would specially like to thank Hiroyuki Nakano and Kei Saeki for generously providing experimental and insightful opinions.

Cystathionine β-Synthase Inhibition Is a Potential Therapeutic Approach to Treatment of Ischemic Injury

PubMed Central

Chan, Su Jing; Chai, Chou; Lim, Tze Wei; Yamamoto, Mie; Lo, Eng H; Lai, Mitchell Kim Peng

2015-01-01

Hydrogen sulfide (H2S) has been reported to exacerbate stroke outcome in experimental models. Cystathionine β-synthase (CBS) has been implicated as the predominant H2S-producing enzyme in central nervous system. When SH-SY5Y cells were transfected to overexpress CBS, these cells were able to synthesize H2S when exposed to high levels of enzyme substrates but not substrate concentrations that may reflect normal physiological conditions. At the same time, these cells demonstrated exacerbated cell death when subjected to oxygen and glucose deprivation (OGD) together with high substrate concentrations, indicating that H2S production has a detrimental effect on cell survival. This effect could be abolished by CBS inhibition. The same effect was observed with primary astrocytes exposed to OGD and high substrates or sodium hydrosulfide. In addition, CBS was upregulated and activated by truncation in primary astrocytes subjected to OGD. When rats were subjected to permanent middle cerebral artery occlusion, CBS activation was also observed. These results imply that in acute ischemic conditions, CBS is upregulated and activated by truncation causing an increased production of H2S, which exacerbate the ischemic injuries. Therefore, CBS inhibition may be a viable approach to stroke treatment. PMID:25873304

Hydroquinone induces DNA hypomethylation-independent overexpression of retroelements in human leukemia and hematopoietic stem cells.

PubMed

Conti, Anastasia; Rota, Federica; Ragni, Enrico; Favero, Chiara; Motta, Valeria; Lazzari, Lorenza; Bollati, Valentina; Fustinoni, Silvia; Dieci, Giorgio

2016-06-10

Hydroquinone (HQ) is an important benzene-derived metabolite associated with acute myelogenous leukemia risk. Although altered DNA methylation has been reported in both benzene-exposed human subjects and HQ-exposed cultured cells, the inventory of benzene metabolite effects on the epigenome is only starting to be established. In this study, we used a monocytic leukemia cell line (THP-1) and hematopoietic stem cells (HSCs) from cord blood to investigate the effects of HQ treatment on the expression of the three most important families of retrotransposons in the human genome: LINE-1, Alu and Endogenous retroviruses (HERVs), that are normally subjected to tight epigenetic silencing. We found a clear tendency towards increased retrotransposon expression in response to HQ exposure, more pronounced in the case of LINE-1 and HERV. Such a partial loss of silencing, however, was generally not associated with HQ-induced DNA hypomethylation. On the other hand, retroelement derepression was also observed in the same cells in response to the hypomethylating agent decitabine. These observations suggest the existence of different types of epigenetic switches operating at human retroelements, and point to retroelement activation in response to benzene-derived metabolites as a novel factor deserving attention in benzene carcinogenesis studies. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of Cancer Stem-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Transformed by Tumor-Derived Extracellular Vesicles

PubMed Central

Yan, Ting; Mizutani, Akifumi; Chen, Ling; Takaki, Mai; Hiramoto, Yuki; Matsuda, Shuichi; Shigehiro, Tsukasa; Kasai, Tomonari; Kudoh, Takayuki; Murakami, Hiroshi; Masuda, Junko; Hendrix, Mary J. C.; Strizzi, Luigi; Salomon, David S.; Fu, Li; Seno, Masaharu

2014-01-01

Several studies have shown that cancer niche can perform an active role in the regulation of tumor cell maintenance and progression through extracellular vesicles-based intercellular communication. However, it has not been reported whether this vesicle-mediated communication affects the malignant transformation of normal stem cells/progenitors. We have previously reported that the conditioned medium derived from the mouse Lewis Lung Carcinoma (LLC) cell line can convert mouse induced pluripotent stem cells (miPSCs) into cancer stem cells (CSCs), indicating that normal stem cells when placed in an aberrant microenvironment can give rise to functionally active CSCs. Here, we focused on the contribution of tumor-derived extracellular vesicles (tEVs) that are secreted from LLC cells to induce the transformation of miPSCs into CSCs. We isolated tEVs from the conditioned medium of LLC cells, and then the differentiating miPSCs were exposed to tEVs for 4 weeks. The resultant tEV treated cells (miPS-LLCev) expressed Nanog and Oct3/4 proteins comparable to miPSCs. The frequency of sphere formation of the miPS-LLCev cells in suspension culture indicated that the self-renewal capacity of the miPS-LLCev cells was significant. When the miPS-LLCev cells were subcutaneously transplanted into Balb/c nude mice, malignant liposarcomas with extensive angiogenesis developed. miPS-LLCevPT and miPS-LLCevDT, the cells established from primary site and disseminated liposarcomas, respectively, showed their capacities to self-renew and differentiate into adipocytes and endothelial cells. Moreover, we confirmed the secondary liposarcoma development when these cells were transplanted. Taken together, these results indicate that miPS-LLCev cells possess CSC properties. Thus, our current study provides the first evidence that tEVs have the potential to induce CSC properties in normal tissue stem cells/progenitors. PMID:25057308

Decreased expression of hepatocyte growth factor in the nitrofen model of congenital diaphragmatic hernia.

PubMed

Takahashi, Toshiaki; Friedmacher, Florian; Zimmer, Julia; Puri, Prem

2016-10-01

Pleuroperitoneal folds (PPFs) are essential for normal diaphragmatic development, representing the only source of the diaphragm's muscle connective tissue. Hepatocyte growth factor (Hgf), which is secreted in PPFs, plays a crucial role in the formation of the muscular diaphragmatic components by regulating the migration of myogenic progenitor cells into the primordial diaphragm. Hgf is also a known downstream target of Gata4 and it has been demonstrated that the expression of Hgf was significantly downregulated in PPF cells of Gata4 knockouts with congenital diaphragmatic hernia (CDH). Furthermore, mutations in PPF-derived cells have been shown to result in CDH. We hypothesized that Hgf expression is decreased in developing diaphragms of fetal rats with nitrofen-induced CDH. Timed-pregnant rats were exposed to either nitrofen or vehicle on gestational day 9 (D9). Fetuses were harvested on selected time-points D13, D15 and D18. Dissected diaphragms (n = 72) were divided into control and nitrofen-exposed specimens (n = 12 per time-point and experimental group, respectively). Diaphragmatic gene expression of Hgf was analyzed by qRT-PCR. Immunofluorescence double staining for Hgf and the mesenchymal marker Gata4 or muscular progenitor marker Myogenin was performed to evaluate protein expression and localization in fetal diaphragms. Relative mRNA expression of Hgf was significantly downregulated in PPFs of nitrofen-exposed fetuses on D13 (3.08 ± 1.46 vs. 5.24 ± 1.93; p < 0.05), developing diaphragms of nitrofen-exposed fetuses on D15 (2.01 ± 0.79 vs. 4.10 ± 1.50; p < 0.05) and fully muscularized diaphragms of nitrofen-exposed fetuses on D18 (1.60 ± 0.78 vs. 3.21 ± 1.89; p < 0.05) compared to controls. Confocal laser scanning microscopy revealed markedly diminished diaphragmatic immunofluorescence of Hgf in nitrofen-exposed fetuses on D13, D15 and D18 compared to controls, which was associated with disruptions in muscle connective tissue formation and reduced myogenic progenitor cell invasion. Decreased diaphragmatic expression of Hgf may disturb the formation of muscle connective tissue in PPFs and thus prevent essential migration of muscle progenitor cells into the developing diaphragm, leading to diaphragmatic defects in the nitrofen CDH model.

Graft protective effect and induction of CD4+Foxp3+ cell by Thrombomodulin on allograft arteriosclerosis in mice.

PubMed

Yin, Enzhi; Matsuyama, Shigefumi; Uchiyama, Masateru; Kawai, Kento; Niimi, Masanori

2018-05-21

Thrombomodulin (TM) is a promising therapeutic natural anti-coagulant, which exerts the effects to control disseminated intravascular coagulation. However, little is known whether TM on micro-vessels could play an important role in the regulation of intimal hyperplasia. We investigated the vessel-protective effect of TM in the survival of fully major histocompatibility complex (MHC)-mismatched murine cardiac allograft transplantation. CBA recipients transplanted with a C57BL/6 heart received intraperitoneal administration of normal saline or 0.2, 2.0, and 20.0 μg/day of TM for 7 days (n = 5, 7, 11, and 11, respectively). Immunohistochemical and fluorescent staining studies were performed to determine whether CD4 + Foxp3 + regulatory T cell were generated at 2 and 4 weeks after grafting. Morphometric analysis for neointimal formation in the coronary arteries of the transplanted allograft was conducted at 2 and 4 weeks after grafting. Untreated CBA recipients rejected C57BL/6 cardiac grafts acutely (median survival time [MST], 7 days). CBA recipients exposed with the above doses had significantly prolonged allograft survival (MSTs, 17, 24 and 50 days, respectively). Morphometric assessment showed that intimal hyperplasia was clearly suppressed in the left and right coronary arteries or allografts from TM-exposed recipients 2 and 4 weeks. Immunohistochemical studies at 2 weeks showed more CD4 + Foxp3 + cells and lower myocardial damage in the allografts from TM-exposed recipients. Notably, fluorescent staining studies demonstrated that TM-exposed recipients 4 weeks post-engraftment had strong aggregation of CD4 + Foxp3 + cells in the intima of the coronary arteries of the cardiac allografts. TM may prolong the survival of fully MHC-mismatched cardiac allografts through suppressing intimal hyperplasia and inducing the accumulation of regulatory CD4 + Foxp3 + cells within coronary arteries.

Postnatal remodeling of the neural components of the epithelial-mesenchymal trophic unit in the proximal airways of infant rhesus monkeys exposed to ozone and allergen.

PubMed

Larson, Shawnessy D; Schelegle, Edward S; Walby, William F; Gershwin, Laural J; Fanuccihi, Michelle V; Evans, Michael J; Joad, Jesse P; Tarkington, Brian K; Hyde, Dallas M; Plopper, Charles G

2004-02-01

Nerves and neuroendocrine cells located within the airway epithelium are ideally situated to sample a changing airway environment, to transmit that information to the central nervous system, and to promote trophic interactions between epithelial and mesenchymal cellular and acellular components. We tested the hypothesis that the environmental stresses of ozone (O(3)) and house dust mite allergen (HDMA) in atopic infant rhesus monkeys alter the distribution of airway nerves. Midlevel bronchi and bronchioles from 6-month-old infant monkeys that inhaled filtered air (FA), house dust mite allergen HDMA, O(3), or HDMA + O(3) for 11 episodes (5 days each, 0.5 ppm O(3), 8 h/day followed by 9 days recovery) were examined using immunohistochemistry for the presence of Protein gene product 9.5 (PGP 9.5), a nonspecific neural indicator, and calcitonin gene-related peptide (CGRP). Along the axial path between the sixth and the seventh intrapulmonary airway generations, there were small significant (P < 0.05) decrements in the density of epithelial nerves in monkeys exposed to HDMA or O(3), while in monkeys exposed to HDMA + O(3) there was a greater significant (P < 0.05) reduction in epithelial innervation. In animals exposed to O(3) or HDMA + O(3) there was a significant increase in the number of PGP 9.5 positive/CGRP negative cells that were anchored to the basal lamina and emitted projections in primarily the lateral plain and often intertwined with projections and cell bodies of other similar cells. We conclude that repeated cycles of acute injury and repair associated with the episodic pattern of ozone and allergen exposure alter the normal development of neural innervation of the epithelial compartment and the appearance of a new population of undefined PGP 9.5 positive cells within the epithelium.

Lactic acidosis switches cancer cells from aerobic glycolysis back to dominant oxidative phosphorylation.

PubMed

Wu, Hao; Ying, Minfeng; Hu, Xun

2016-06-28

While transformation of normal cells to cancer cells is accompanied with a switch from oxidative phosphorylation (OXPHOS) to aerobic glycolysis, it is interesting to ask if cancer cells can revert from Warburg effect to OXPHOS. Our previous works suggested that cancer cells reverted to OXPHOS, when they were exposed to lactic acidosis, a common factor in tumor environment. However, the conclusion cannot be drawn unless ATP output from glycolysis and OXPHOS is quantitatively determined. Here we quantitatively measured ATP generation from glycolysis and OXPHOS in 9 randomly selected cancer cell lines. Without lactic acidosis, glycolysis and OXPHOS generated 23.7% - 52.2 % and 47.8% - 76.3% of total ATP, respectively; with lactic acidosis (20 mM lactate with pH 6.7), glycolysis and OXPHOS provided 5.7% - 13.4% and 86.6% - 94.3% of total ATP. We concluded that cancer cells under lactic acidosis reverted from Warburg effect to OXPHOS phenotype.

The TP53 dependence of radiation-induced chromosome instability in human lymphoblastoid cells

NASA Technical Reports Server (NTRS)

Schwartz, Jeffrey L.; Jordan, Robert; Evans, Helen H.; Lenarczyk, Marek; Liber, Howard

2003-01-01

The dose and TP53 dependence for the induction of chromosome instability were examined in cells of three human lymphoblastoid cell lines derived from WIL2 cells: TK6, a TP53-normal cell line, NH32, a TP53-knockout created from TK6, and WTK1, a WIL2-derived cell line that spontaneously developed a TP53 mutation. Cells of each cell line were exposed to (137)Cs gamma rays, and then surviving clones were isolated and expanded in culture for approximately 35 generations before the frequency and characteristics of the instability were analyzed. The presence of dicentric chromosomes, formed by end-to-end fusions, served as a marker of chromosomal instability. Unexposed TK6 cells had low levels of chromosomal instability (0.002 +/- 0.001 dicentrics/cell). Exposure of TK6 cells to doses as low as 5 cGy gamma rays increased chromosome instability levels nearly 10-fold to 0.019 +/- 0.008 dicentrics/cell. There was no further increase in instability levels beyond 5 cGy. In contrast to TK6 cells, unexposed cultures of WTK1 and NH32 cells had much higher levels of chromosome instability of 0.034 +/- 0.007 and 0.041 +/- 0.009, respectively, but showed little if any effect of radiation on levels of chromosome instability. The results suggest that radiation exposure alters the normal TP53-dependent cell cycle checkpoint controls that recognize alterations in telomere structure and activate apoptosis.

Genetic Analysis of T Cell Lymphomas in Carbon Ion-Irradiated Mice Reveals Frequent Interstitial Chromosome Deletions: Implications for Second Cancer Induction in Normal Tissues during Carbon Ion Radiotherapy.

PubMed

Blyth, Benjamin J; Kakinuma, Shizuko; Sunaoshi, Masaaki; Amasaki, Yoshiko; Hirano-Sakairi, Shinobu; Ogawa, Kanae; Shirakami, Ayana; Shang, Yi; Tsuruoka, Chizuru; Nishimura, Mayumi; Shimada, Yoshiya

2015-01-01

Monitoring mice exposed to carbon ion radiotherapy provides an indirect method to evaluate the potential for second cancer induction in normal tissues outside the radiotherapy target volume, since such estimates are not yet possible from historical patient data. Here, male and female B6C3F1 mice were given single or fractionated whole-body exposure(s) to a monoenergetic carbon ion radiotherapy beam at the Heavy Ion Medical Accelerator in Chiba, Japan, matching the radiation quality delivered to the normal tissue ahead of the tumour volume (average linear energy transfer = 13 keV x μm(-1)) during patient radiotherapy protocols. The mice were monitored for the remainder of their lifespan, and a large number of T cell lymphomas that arose in these mice were analysed alongside those arising following an equivalent dose of 137Cs gamma ray-irradiation. Using genome-wide DNA copy number analysis to identify genomic loci involved in radiation-induced lymphomagenesis and subsequent detailed analysis of Notch1, Ikzf1, Pten, Trp53 and Bcl11b genes, we compared the genetic profile of the carbon ion- and gamma ray-induced tumours. The canonical set of genes previously associated with radiation-induced T cell lymphoma was identified in both radiation groups. While the pattern of disruption of the various pathways was somewhat different between the radiation types, most notably Pten mutation frequency and loss of heterozygosity flanking Bcl11b, the most striking finding was the observation of large interstitial deletions at various sites across the genome in carbon ion-induced tumours, which were only seen infrequently in the gamma ray-induced tumours analysed. If such large interstitial chromosomal deletions are a characteristic lesion of carbon ion irradiation, even when using the low linear energy transfer radiation to which normal tissues are exposed in radiotherapy patients, understanding the dose-response and tissue specificity of such DNA damage could prove key to assessing second cancer risk in carbon ion radiotherapy patients.

Recent advances in our understanding of giant cell arteritis pathogenesis.

PubMed

Samson, Maxime; Corbera-Bellalta, Marc; Audia, Sylvain; Planas-Rigol, Ester; Martin, Laurent; Cid, Maria Cinta; Bonnotte, Bernard

2017-08-01

Giant cell arteritis (GCA) is a granulomatous vasculitis affecting large arteries, especially the aorta and the extracranial branches of the external carotid artery. Its exact pathogenesis is not fully understood but major progress has been made in recent years, leading to new therapeutic targets like inhibition of the interleukin-6 pathway or the modulation of immune checkpoints. The cause of GCA has not been clearly identified but it is thought that GCA occurs on a genetic background and is triggered by unknown environmental factors that could activate and lead to the maturation of dendritic cells localized in the adventitia of normal arteries. These activated dendritic cells then produce chemokines which trigger the recruitment of CD4 + T cells, which in turn become activated, proliferate and polarize into Th1 and Th17 cells, which produce IFN-γ and IL-17, respectively. Exposed to IFN-γ, endothelial cells and vascular smooth muscle cells produce chemokines leading to the recruitment of further Th1 cells, CD8 + T cells and monocytes. The latter differentiate into macrophages, which, when persistently exposed to IFN-γ, form giant cells, the histological hallmark of GCA. With the contribution of vascular smooth muscle cells, immune cells then trigger the destruction and remodeling of the arterial wall, thus leading to the formation of a neo-intima resulting in progressive occlusion of the arterial lumen, which is responsible for the ischemic symptoms of GCA. In this paper, we review recent progress in our understanding of GCA pathogenesis in the fields of genetics, epigenetics, infections, immunology and vascular remodeling. Copyright © 2017 Elsevier B.V. All rights reserved.

UVB radiation and human monocyte accessory function: Differential effects on pre-mitotic events in T-cell activation

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

Krutmann, J.K.; Kammer, G.M.; Toossi, Z.

Purified T lymphocytes fail to proliferate in response to antigenic and mitogenic stimuli when cultured in the presence of accessory cells that have been exposed in vitro to sublethal doses of UVB radiation. Because proliferation represents a final stage in the T-cell activation process, the present study was conducted to determine whether T cells were able to progress through any of the pre-mitotic stages when UVB-irradiated monocytes were used as model accessory cells. In these experiments, monoclonal anti-CD3 antibodies were employed as the mitogenic stimulus. Culture of T cells with UVB-irradiated monocytes did allow the T cells to undergo anmore » increase in intracellular free calcium, which is one of the first steps in the activation sequence. The T cells expressed interleukin-2 receptors, although at a reduced level. However, T cells failed to produce interleukin-2 above background levels when they were placed in culture with monocytes exposed to UVB doses as low as 50 J/m2. Incubation of T cells with UVB-irradiated monocytes did not affect the subsequent capacity of T cells to proliferate, since they developed a normal proliferative response in secondary culture when restimulated with anti-CD3 antibodies and unirradiated monocytes. These studies indicate that T lymphocytes become partially activated when cultured with UVB-irradiated monocytes and mitogenic anti-CD3 monoclonal antibodies. In addition, they suggest that interleukin-2 production is the T-cell activation step most sensitive to inhibition when UVB-irradiated monocytes are employed as accessory cells.« less

The scorpion venom peptide BmKn2 induces apoptosis in cancerous but not in normal human oral cells.

PubMed

Satitmanwiwat, Saranya; Changsangfa, Chinarat; Khanuengthong, Anuson; Promthep, Kornkanok; Roytrakul, Sittiruk; Arpornsuwan, Teerakul; Saikhun, Kulnasan; Sritanaudomchai, Hathaitip

2016-12-01

This study aimed to investigate the mechanism of the induction of apoptosis of human oral cancer cells by the scorpion venom peptide BmKn2. Human oral squamous carcinoma cells (HSC4), mouth epidermoid carcinoma cells (KB), human normal gingival cells (HGC) and dental pulp cells (DPC) were treated with BmKn-2 peptide for 24h. Cell viability was determined by the MTT assay. Apoptosis was assessed using phase contrast microscopy, by propidium iodide (PI) staining to assess nuclear morphology and by Annexin V staining. Apoptotic signaling pathways were investigated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and Western blotting. BmKn-2 showed potent cytotoxic effects towards both HSC4 and KB cells with the associated induction of apoptosis. The cells showed distinct morphological changes, nuclear disintegration and an increase in the number of Annexin V-positive cells. Interestingly, at concentrations which kill cancerous cells, BmKn-2 did not affect cell viability or mediate the induction of apoptosis in normal HGC or DPC. Induction of apoptosis by BmKn-2 in HSC4 and KB cells was associated with the activation of tumor suppress p53. Pro-apoptotic BAX expression was increased, whereas antiapoptotic BCL-2 expression was decreased in BmKn-2 exposed HSC4 and KB cells. BmKn-2 treated-oral cancer cells showed distinct upregulation of initiator caspase-9, with no effect on caspase-8 expression. Increased expression levels of executor caspases-3 and -7 were also found in treated cells for both oral cancers. This study has suggested for the first time that BmKn-2 exerts selective cytotoxic effects on human oral cancer cells by inducting apoptosis via a p53-dependent intrinsic apoptotic pathway. BmKn-2 peptide originally derived from a natural source shows great promise as a candidate treatment for oral cancer, with minimal effects on healthy tissue. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Asbestos-associated genome-wide DNA methylation changes in lung cancer.

PubMed

Kettunen, Eeva; Hernandez-Vargas, Hector; Cros, Marie-Pierre; Durand, Geoffroy; Le Calvez-Kelm, Florence; Stuopelyte, Kristina; Jarmalaite, Sonata; Salmenkivi, Kaisa; Anttila, Sisko; Wolff, Henrik; Herceg, Zdenko; Husgafvel-Pursiainen, Kirsti

2017-11-15

Previous studies have revealed a robust association between exposure to asbestos and human lung cancer. Accumulating evidence has highlighted the role of epigenome deregulation in the mechanism of carcinogen-induced malignancies. We examined the impact of asbestos on DNA methylation. Our genome-wide studies (using Illumina HumanMethylation450K BeadChip) of lung cancer tissue and paired normal lung from 28 asbestos-exposed or non-exposed patients, mostly smokers, revealed distinctive DNA methylation changes. We identified a number of differentially methylated regions (DMR) and differentially variable, differentially methylated CpGs (DVMC), with individual CpGs further validated by pyrosequencing in an independent series of 91 non-small cell lung cancer and paired normal lung. We discovered and validated BEND4, ZSCAN31 and GPR135 as significantly hypermethylated in lung cancer. DMRs in genes such as RARB (FDR 1.1 × 10 -19 , mean change in beta [Δ] -0.09), GPR135 (FDR 1.87 × 10 -8 , mean Δ -0.09) and TPO (FDR 8.58 × 10 -5 , mean Δ -0.11), and DVMCs in NPTN, NRG2, GLT25D2 and TRPC3 (all with p <0.05, t-test) were significantly associated with asbestos exposure status in exposed versus non-exposed lung tumors. Hypomethylation was characteristic to DVMCs in lung cancer tissue from asbestos-exposed subjects. When DVMCs related to asbestos or smoking were analyzed, 96% of the elements were unique to either of the exposures, consistent with the concept that the methylation changes in tumors may be specific for risk factors. In conclusion, we identified novel DNA methylation changes associated with lung tumors and asbestos exposure, suggesting that changes may be present in causal pathway from asbestos exposure to lung cancer. © 2017 UICC.

Temporal and speech processing skills in normal hearing individuals exposed to occupational noise.

PubMed

Kumar, U Ajith; Ameenudin, Syed; Sangamanatha, A V

2012-01-01

Prolonged exposure to high levels of occupational noise can cause damage to hair cells in the cochlea and result in permanent noise-induced cochlear hearing loss. Consequences of cochlear hearing loss on speech perception and psychophysical abilities have been well documented. Primary goal of this research was to explore temporal processing and speech perception Skills in individuals who are exposed to occupational noise of more than 80 dBA and not yet incurred clinically significant threshold shifts. Contribution of temporal processing skills to speech perception in adverse listening situation was also evaluated. A total of 118 participants took part in this research. Participants comprised three groups of train drivers in the age range of 30-40 (n= 13), 41 50 ( = 13), 41-50 (n = 9), and 51-60 (n = 6) years and their non-noise-exposed counterparts (n = 30 in each age group). Participants of all the groups including the train drivers had hearing sensitivity within 25 dB HL in the octave frequencies between 250 and 8 kHz. Temporal processing was evaluated using gap detection, modulation detection, and duration pattern tests. Speech recognition was tested in presence multi-talker babble at -5dB SNR. Differences between experimental and control groups were analyzed using ANOVA and independent sample t-tests. Results showed a trend of reduced temporal processing skills in individuals with noise exposure. These deficits were observed despite normal peripheral hearing sensitivity. Speech recognition scores in the presence of noise were also significantly poor in noise-exposed group. Furthermore, poor temporal processing skills partially accounted for the speech recognition difficulties exhibited by the noise-exposed individuals. These results suggest that noise can cause significant distortions in the processing of suprathreshold temporal cues which may add to difficulties in hearing in adverse listening conditions.

New decision support tool for acute lymphoblastic leukemia classification

NASA Astrophysics Data System (ADS)

Madhukar, Monica; Agaian, Sos; Chronopoulos, Anthony T.

2012-03-01

In this paper, we build up a new decision support tool to improve treatment intensity choice in childhood ALL. The developed system includes different methods to accurately measure furthermore cell properties in microscope blood film images. The blood images are exposed to series of pre-processing steps which include color correlation, and contrast enhancement. By performing K-means clustering on the resultant images, the nuclei of the cells under consideration are obtained. Shape features and texture features are then extracted for classification. The system is further tested on the classification of spectra measured from the cell nuclei in blood samples in order to distinguish normal cells from those affected by Acute Lymphoblastic Leukemia. The results show that the proposed system robustly segments and classifies acute lymphoblastic leukemia based on complete microscopic blood images.

Studies on the therapeutic effect of propolis in streptozotocin-induced diabetic mice

NASA Astrophysics Data System (ADS)

Rifa'I, Muhaimin

2017-05-01

Propolis oral administration in diabetic mice can increase the expression of TLR-3 and ameliorate homeostatic imbalance. The TLR-3 expression increased in both B cells and T cells. In this study, we also found that propolis may improve insulin expression in pancreatic beta cells. Administering propolis at a dose of 100-200 mg/mL may significantly increase insulin synthesis. Propolis might protect healthy cells from apoptosis in cisplatin exposure. Cisplatin can induce spleen cells to remain in the G0/G1 phase or to reach the apoptosis stage in the absence of propolis. In contrast, cisplatin, when administered together with propolis to a culture of spleen cells, cannot force the cells to undergo apoptosis. In a culture of spleen cells in the presence of propolis, the cells did not show any responses. This suggests that propolis does not disrupt normal cell physiology and supports cell health when cells are exposed to cisplatin. Furthermore, propolis can suppress the production of the pro-inflammatory cytokine interferon-gamma (IFN-γ).

Repair dentinogenesis following transplantation into normal and germ-free animals.

PubMed

Inoue, T; Shimono, M

1992-01-01

The purpose of this study was to investigate the dentinogenesis of dental pulp tissue following transplantation and during regeneration in normal and germ free animals, as well as in vitro experiments. (1) Partial and complete exposure of dental pulp in germ free rats by removing the enamel and dentin of molars. (2) The central portion of rat incisor which consisted of pulp and pulp chamber were autografted into various tissues. (3) Explants of rat pulp tissue were cultured on dentin matrix. (4) Resin bonding agent, 4-META/MMA-TBB-O (Superbond), was placed directly on surgically-exposed dental pulp. (1) Dentin bridge formation was recognized at 5 days after operation in germ free rat. (2) The cut surface of the transplant exhibited dentin bridge at 7 days after implantation, and the thickness of the newly formed dentin increased gradually thereafter up to 30 days. (3) Cultured pulp cells had high alkaline phosphatase activity and bone- or dentin-like hard tissue was synthesized on the dentin matrix in vitro. (4) Dentin bridge formation was evident on the surgically-exposed dental pulp even after application of Superbond. From these results, it is suggested that pulp tissue has a high activity of dentinogenesis both in vivo and in vitro and 3 days is enough for pulp cells to express the odontoblast phenotype when inflammatory factors are not present.

Spermatogenesis is not impaired in a nucleotide excision repair-deficient min mouse model with or without neonatal mutagen treatment.

PubMed

Andreassen, Ashild; Steffensen, Inger-Lise; Olsen, Ann-Karin; Tanaka, Kiyoji; Wiger, Richard

2011-01-01

Mice deficient in the xeroderma pigmentosum group A gene (Xpa) exhibit impaired nucleotide excision repair (NER) and are expected to accumulate bulky DNA adducts when subjected to certain compounds (eg, heterocyclic amines). Multiple intestinal neoplasia (Min) mice (B6(Min)(/+)) are particularly sensitive to low concentrations of mutagenic compounds in food. They develop intestinal tumors spontaneously, and the number and size of the tumors increase following exposure to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), which humans are exposed to via fried food. We previously reported that NER is inefficient in adult testicular cells. Reduced NER (genetic deficiency; Xpa(-/-)) is expected to represent risk factors for PhIP-induced genotoxicity and could possibly disturb spermatogenesis, particularly in B6(Min)(/+) mice. We therefore studied spermatogenesis in mice with combinations of Xpa and Min or wild-type genotypes 11 weeks after exposure to PhIP on days 3 to 6. Fewer offspring were obtained from B6(Min)(/+)Xpa(-/-) than from B6(Min)(/+)Xpa(+/+) or B6(Min)(/+)Xpa(+/-). Distributions of the different testicular cell types, indicative of normal spermatogenesis and relative testes weights, did not differ significantly in PhIP-exposed or unexposed mice regardless of their genotypes. We conclude that the removal of bulky DNA adducts does not seem to be essential for normal spermatogenesis.

Regulation of matrix metalloproteinase-9 (MMP-9), tissue inhibitor of MMP, and progesterone secretion in luteinized granulosa cells from normally ovulating women with polycystic ovary disease.

PubMed

Ben-Shlomo, Izhar; Goldman, Shlomit; Shalev, Eliezer

2003-03-01

To investigate the regulation of MMP-9, TIMP-1, and progesterone via three signal transduction pathways in luteinized granulosa cells from normal ovulatory and PCOD women. In vitro study. Laboratory for Research in Reproductive Sciences, Department of Obstetrics and Gynecology, Ha'Emek Hospital, Afula, Israel. Ten normal ovulatory and 10 women with polycystic ovary disease (PCOD) treated in an assisted reproduction program. Cultured cells were exposed to phorbol 12-myristate 13-acetate (TPA), acting via protein kinase C (PKC), to epidermal growth factor (EGF), acting via protein tyrosine kinase (PTK), and to forskolin, acting via protein kinase A (PKA). Secretion of MMP-9, TIMP-1, and progesterone. Phorbol 12-myristate 13-acetate elicited an increase in MMP-9 and TIMP-1 secretion in both groups and apparently did not affect progesterone secretion. Epidermal growth factor did not change significantly neither MMP-9 nor TIMP-1 secretion but dose dependently decreased MMP-9-TIMP-1 ratio and increased progesterone secretion in the PCOD group. Forskolin inhibited MMP-9 activity and increased TIMP-1 and progesterone secretion in both groups. Progesterone production was inversely related to the ratio of MMP-9-TIMP-1 regardless of cell origin. In this preliminary study, similar and divergent patterns have emerged in the regulation of MMP-9 and TIMP-1 in human luteinized granulosa cells. Repressing MMP-9-TIMP-1 ratio may have an important modulatory effect on progesterone secretion.

Reduction of arsenite-enhanced ultraviolet radiation-induced DNA damage by supplemental zinc

PubMed Central

Cooper, Karen L.; King, Brenee S.; Sandoval, Monica M.; Liu, Ke Jian; Hudson, Laurie G.

2013-01-01

Arsenic is a recognized human carcinogen and there is evidence that arsenic augments the carcinogenicity of DNA damaging agents such as ultraviolet radiation (UVR) thereby acting as a co-carcinogen. Inhibition of DNA repair is one proposed mechanism to account for the co-carcinogenic actions of arsenic. We and others find that arsenite interferes with the function of certain zinc finger DNA repair proteins. Furthermore, we reported that zinc reverses the effects of arsenite in cultured cells and a DNA repair target protein, poly (ADP-ribose) polymerase-1. In order to determine whether zinc ameliorates the effects of arsenite on UVR-induced DNA damage in human keratinocytes and in an in vivo model, normal human epidermal keratinocytes and SKH-1 hairless mice were exposed to arsenite, zinc or both before solar-simulated (ss) UVR exposure. Poly (ADP-ribose) polymerase activity, DNA damage and mutation frequencies at the hprt locus were measured in each treatment group in normal human keratinocytes. DNA damage was assessed in vivo by immunohistochemical staining of skin sections isolated from SKH-1 hairless mice. Cell-based findings demonstrate that ssUVR-induced DNA damage and mutagenesis are enhanced by arsenite, and supplemental zinc partially reverses the arsenite effect. In vivo studies confirm that zinc supplementation decreases arsenite-enhanced DNA damage in response to ssUVR exposure. From these data we can conclude that zinc offsets the impact of arsenic on ssUVR-stimulated DNA damage in cells and in vivo suggesting that zinc supplementation may provide a strategy to improve DNA repair capacity in arsenic exposed human populations. PMID:23523584

Aberrant light directly impairs mood and learning through melanopsin-expressing neurons.

PubMed

LeGates, Tara A; Altimus, Cara M; Wang, Hui; Lee, Hey-Kyoung; Yang, Sunggu; Zhao, Haiqing; Kirkwood, Alfredo; Weber, E Todd; Hattar, Samer

2012-11-22

The daily solar cycle allows organisms to synchronize their circadian rhythms and sleep-wake cycles to the correct temporal niche. Changes in day-length, shift-work, and transmeridian travel lead to mood alterations and cognitive function deficits. Sleep deprivation and circadian disruption underlie mood and cognitive disorders associated with irregular light schedules. Whether irregular light schedules directly affect mood and cognitive functions in the context of normal sleep and circadian rhythms remains unclear. Here we show, using an aberrant light cycle that neither changes the amount and architecture of sleep nor causes changes in the circadian timing system, that light directly regulates mood-related behaviours and cognitive functions in mice. Animals exposed to the aberrant light cycle maintain daily corticosterone rhythms, but the overall levels of corticosterone are increased. Despite normal circadian and sleep structures, these animals show increased depression-like behaviours and impaired hippocampal long-term potentiation and learning. Administration of the antidepressant drugs fluoxetine or desipramine restores learning in mice exposed to the aberrant light cycle, suggesting that the mood deficit precedes the learning impairments. To determine the retinal circuits underlying this impairment of mood and learning, we examined the behavioural consequences of this light cycle in animals that lack intrinsically photosensitive retinal ganglion cells. In these animals, the aberrant light cycle does not impair mood and learning, despite the presence of the conventional retinal ganglion cells and the ability of these animals to detect light for image formation. These findings demonstrate the ability of light to influence cognitive and mood functions directly through intrinsically photosensitive retinal ganglion cells.

Effects of humidified and dry air on corneal endothelial cells during vitreal fluid-air exchange.

PubMed

Cekiç, Osman; Ohji, Masahito; Hayashi, Atsushi; Fang, Xiao Y; Kusaka, Shunji; Tano, Yasuo

2002-07-01

To report the immediate anatomic and functional alterations in corneal endothelial cells following use of humidified air and dry air during vitreal fluid-air exchange in rabbits. Experimental study. Rabbits undergoing pars plana vitrectomy and lensectomy were perfused with either dry or humidified air during fluid-air exchange for designated durations. Three different experiments were performed. First, control and experimental corneas were examined by scanning electron microscopy (SEM). Second, corneas were stained with Phalloidin-FITC and examined by fluorescein microscopy. Finally, third, transendothelial permeability for carboxyfluorescein was determined using a diffusion chamber. While different from the corneal endothelial cells, those cells exposed to humidified air were less stressed than cells exposed to dry air by SEM. Actin cytoskeleton was found highly disorganized with dry air exposure. Humidified air maintained the normal actin cytoskeleton throughout the 20 minutes of fluid-air exchange. Paracellular carboxyfluorescein leakage was significantly higher in dry air insufflated eyes compared with that of the humidified air after 5, 10, and 20 minutes of fluid-air exchange (P =.002, P =.004, and P =.002, respectively). Dry air stress during fluid-air exchange causes significant immediate alterations in monolayer appearance, actin cytoskeleton, and barrier function of corneal endothelium in aphakic rabbit eyes. Use of humidified air largely prevents the alterations in monolayer appearance, actin cytoskeleton, and barrier function of corneal endothelial cells.

Role of epidermal stem cells in repair of partial-thickness burn injury after using Moist Exposed Burn Ointment (MEBO(®)) histological and immunohistochemical study.

PubMed

El-Hadidy, M R; El-Hadidy, A R; Bhaa, A; Asker, S A; Mazroa, S A

2014-04-01

Moist Exposed Burn Ointment (MEBO(®)) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of hindlimb unloading and partial weight suspension models for spaceflight-type condition induced effects on white blood cells

NASA Astrophysics Data System (ADS)

Wilson, Jolaine M.; Krigsfeld, Gabriel S.; Sanzari, Jenine K.; Wagner, Erika B.; Mick, Rosemarie; Kennedy, Ann R.

2012-01-01

Animal models are frequently used to assist in the determination of the long- and short-term effects of space flight. The space environment, including microgravity, can impact many physiological and immunological system parameters. It has been found that ground based models of microgravity produce changes in white blood cell counts, which negatively affects immunologic function. As part of the Center of Acute Radiation Research (CARR), we compared the acute effects on white blood cell parameters induced by the more traditionally used animal model of hindlimb unloading (HU) with a recently developed reduced weightbearing analog known as partial weight suspension (PWS). Female ICR mice were either hindlimb unloaded or placed in the PWS system at 16% quadrupedal weightbearing for 4 h, 1, 2, 7 or 10 days, at which point complete blood counts were obtained. Control animals (jacketed and non-jacketed) were exposed to identical conditions without reduced weightbearing. Results indicate that significant changes in total white blood cell (WBC), neutrophil, lymphocyte, monocyte and eosinophil counts were observed within the first 2 days of exposure to each system. These differences in blood cell counts normalized by day 7 in both systems. The results of these studies indicate that there are some statistically significant changes observed in the blood cell counts for animals exposed to both the PWS and HU simulated microgravity systems.

Thin film photovoltaic cells having increased durability and operating life and method for making same

DOEpatents

Barnett, Allen M.; Masi, James V.; Hall, Robert B.

1980-12-16

A solar cell having a copper-bearing absorber is provided with a composite transparent encapsulating layer specifically designed to prevent oxidation of the copper sulfide. In a preferred embodiment, the absorber is a layer of copper sulfide and the composite layer comprises a thin layer of copper oxide formed on the copper sulfide and a layer of encapsulating glass formed on the oxide. It is anticipated that such devices, when exposed to normal operating conditions of various terrestrial applications, can be maintained at energy conversion efficiencies greater than one-half the original conversion efficiency for periods as long as thirty years.

Induction of chromatin damage and distribution of isochromatid breaks in human fibroblast cells exposed to heavy ions

NASA Technical Reports Server (NTRS)

Kawata, Tetsuya; Ito, Hisao; Motoori, Ken; Ueda, Takuya; Shigematsu, Naoyuki; Furusawa, Yoshiya; Durante, Marco; George, Kerry; Wu, Honglu; Cucinotta, Francis A.

2002-01-01

The frequency of chromatid breaks and the distribution of isochromatid breaks were measured in G2-phase normal human fibroblasts prematurely condensed a short time after exposure to low- or high-LET radiations. The average number of isochromatid breaks from a single particle traversal increased with increasing LET values, while the average number of chromatid-type breaks appeared to reach a plateau. The distribution of isochromatid breaks after high-LET iron particles exposure was overdispersed compared to gamma-rays, indicating that a single iron particle traversal through a cell nucleus can produce multiple isochromatid breaks.

Induction of chromatin damage and distribution of isochromatid breaks in human fibroblast cells exposed to heavy ions.

PubMed

Kawata, Tetsuya; Ito, Hisao; Motoori, Ken; Ueda, Takuya; Shigematsu, Naoyuki; Furusawa, Yoshiya; Durante, Marco; George, Kerry; Wu, Honglu; Cucinotta, Francis A

2002-12-01

The frequency of chromatid breaks and the distribution of isochromatid breaks were measured in G2-phase normal human fibroblasts prematurely condensed a short time after exposure to low- or high-LET radiations. The average number of isochromatid breaks from a single particle traversal increased with increasing LET values, while the average number of chromatid-type breaks appeared to reach a plateau. The distribution of isochromatid breaks after high-LET iron particles exposure was overdispersed compared to gamma-rays, indicating that a single iron particle traversal through a cell nucleus can produce multiple isochromatid breaks.

Survival of Listeria monocytogenes strain H7762 and resistance to simulated gastric fluid following exposure to frankfurter exudate.

PubMed

Wonderling, Laura D; Bayles, Darrell O

2004-06-01

Listeria monocytogenes strain H7762, a frankfurter isolate, was tested to determine whether it was able to survive at 4 degrees C in frankfurter pack fluid (exudate) and to determine whether food exposure affects its acid sensitivity. Cultures were sampled and tested for acid sensitivity by challenge with simulated gastric fluid (SGF). SGF challenges performed immediately after inoculation revealed that between 20 and 26% of the cells survived the full 30 min of SGF challenge regardless of whether the cells were inoculated into brain heart infusion broth (BHI) or exudate. After 2 days of incubation, cells exposed to both exudate and BHI had significantly decreased SGF resistance; however, the cells exposed to exudate were significantly more SGF resistant than cells exposed to BHI (after 15 min of SGF treatment, 33% of the exudate-exposed cells survived and 12% of the BHI-exposed cells survived). L. monocytogenes exposed to exudate had greater SGF resistance at all challenge times compared with BHI-exposed cells from day 2 through day 4. From days 8 to 15, exudate-exposed cells continued to have greater SGF resistance than BHI-exposed cells up to 10 min of SGF challenge but were as sensitive as the BHI-exposed cells at 20 to 30 min of challenge. By day 25, cells exposed to exudate were significantly more sensitive to SGF challenge than BHI-exposed cells. The survivor data generated from SGF challenges were modeled by a nonlinear regression analysis to calculate the underlying distribution of SGF resistance found in the challenged populations. These analyses indicated that L. monocytogenes exposed to exudate at 4 degrees C had a broader distribution of resistance to SGF compared with cells exposed to BHI at 4 degrees C. In addition, the mean time of death during SGF treatment was greater after exposure to exudate, indicating that cells exposed to exudate were more resistant to killing by SGF These data suggest that exposure to frankfurter exudate might render L. monocytogenes more able to survive the stomach environment during the initial stages of infection.

Dietary, nondigestible oligosaccharides and Bifidobacterium breve M-16V suppress allergic inflammation in intestine via targeting dendritic cell maturation.

PubMed

de Kivit, Sander; Kostadinova, Atanaska I; Kerperien, JoAnn; Morgan, Mary E; Muruzabal, Veronica Ayechu; Hofman, Gerard A; Knippels, Leon M J; Kraneveld, Aletta D; Garssen, Johan; Willemsen, Linette E M

2017-07-01

Dietary intervention with short-chain galacto-oligosaccharides (scGOS), long-chain fructo-oligosaccharides (lcFOS) and Bifidobacterium breve M-16V ( Bb ) (GF/ Bb ) suppresses food allergic symptoms in mice, potentially via intestinal epithelial cell (IEC)-derived galectin-9. Furthermore, in vitro studies showed galacto- and fructo-oligosaccharides (GF) to enhance the immunomodulatory capacity of a TLR9 ligand representing bacterial CpG DNA when exposed to IEC. In this study, we investigated whether GF/ Bb modulates dendritic cells (DCs) and subsequent Th2 and regulatory T cell (T reg ) frequency in the small intestinal lamina propria (SI-LP). BALB/c mice were fed GF/ Bb during oral OVA sensitization. DC and T cell phenotype were determined in SI-LP mononuclear cells using flow cytometry. Murine bone marrow-derived DCs (BMDCs) were exposed to recombinant galectin-9 or human monocyte-derived DCs (moDCs) and were cultured in IEC-conditioned medium from GF and TLR9 ligand-exposed HT-29 cells. GF/ Bb reduced allergic symptoms and enhanced serum galectin-9 levels, while suppressing activation, restoring phagocytic capacity, and normalizing CD103 expression of SI-LP DCs of OVA-allergic mice. In vitro, galectin-9 suppressed LPS-induced activation markers and cytokine secretion by BMDCs, and IEC-conditioned medium suppressed moDC activation in a galectin-9-dependent manner. Besides suppression of SI-LP DC activation, dietary GF/ Bb also lowered the frequency of activated Th2 cells, while enhancing T reg in the SI-LP of OVA-allergic mice compared to the control diet. Dietary intervention with GF/ Bb enhances galectin-9 and suppresses allergic symptoms of OVA-allergic mice in association with reduced intestinal DC and Th2 activation and increased T reg frequency in these mice. © Society for Leukocyte Biology.

The large-conductance calcium-activated potassium channel holds the key to the conundrum of familial hypokalemic periodic paralysis

PubMed Central

Kim, Sung-Jo; Kang, Sun-Yang; Yi, Jin Woong; Kim, Seung-Min

2014-01-01

Purpose Familial hypokalemic periodic paralysis (HOKPP) is an autosomal dominant channelopathy characterized by episodic attacks of muscle weakness and hypokalemia. Mutations in the calcium channel gene, CACNA1S, or the sodium channel gene, SCN4A, have been found to be responsible for HOKPP; however, the mechanism that causes hypokalemia remains to be determined. The aim of this study was to improve the understanding of this mechanism by investigating the expression of calcium-activated potassium (KCa) channel genes in HOKPP patients. Methods We measured the intracellular calcium concentration with fura-2-acetoxymethyl ester in skeletal muscle cells of HOKPP patients and healthy individuals. We examined the mRNA and protein expression of KCa channel genes (KCNMA1, KCNN1, KCNN2, KCNN3, and KCNN4) in both cell types. Results Patient cells exhibited higher cytosolic calcium levels than normal cells. Quantitative reverse transcription polymerase chain reaction analysis showed that the mRNA levels of the KCa channel genes did not significantly differ between patient and normal cells. However, western blot analysis showed that protein levels of the KCNMA1 gene, which encodes KCa1.1 channels (also called big potassium channels), were significantly lower in the membrane fraction and higher in the cytosolic fraction of patient cells than normal cells. When patient cells were exposed to 50 mM potassium buffer, which was used to induce depolarization, the altered subcellular distribution of BK channels remained unchanged. Conclusion These findings suggest a novel mechanism for the development of hypokalemia and paralysis in HOKPP and demonstrate a connection between disease-associated mutations in calcium/sodium channels and pathogenic changes in nonmutant potassium channels. PMID:25379045

Protective Role of Eosinophils and TNFa after Ozone Inhalation.

PubMed

Fryer, Allison D; Jacoby, David B; Wicher, Sarah A

2017-03-01

Exposure to ozone induces deleterious responses in the airways that include shortness of breath, inflammation, and bronchoconstriction. People with asthma have increased airway sensitivity to ozone and other irritants. Dr. Allison Fryer and colleagues addressed how exposure to ozone affects the immune and physiological responses in guinea pigs. Guinea pigs are considered a useful animal model for studies of respiratory and physiological responses in humans; their response to airborne allergens is similar to that in humans and shares some features of allergic asthma. Fryer and colleagues had previously observed that within 24 hours of exposure, ozone not only induced bronchoconstriction but also stimulated the production of new cells in the bone marrow, where all white blood cells develop. As a result of ozone exposure, increased numbers of newly synthesized white blood cells, particularly eosinophils, moved into the blood and lungs. The central hypothesis of the current study was that newly synthesized eosinophils recruited to the lungs 3 days after ozone exposure were beneficial to the animals because they reduced ozoneinduced bronchoconstriction. The investigators also hypothesized that the beneficial effect seen in normal (nonsensitized) animals was lost in animals that had been injected with an allergen, ovalbumin (sensitized). They also planned to explore the effects of inhibitors of certain cytokines (cellsignaling molecules). Immune responses in sensitized animals are dominated by a Th2 pattern, which is characterized by the synthesis of cytokines (interleukin [IL]-4, IL-5, and IL-13) and the Th2 subset of CD4+ T lymphocytes and the cells they activate (predominantly eosinophils, and B lymphocytes that switch to making immunoglobulin E [IgE]). Thus, sensitized animals were used as a model of allergic humans, whose immune responses tend to be dominated by IgE. Fryer and colleagues exposed normal and sensitized (allergic) guinea pigs to 2 ppm ozone or filtered air for 4 hours and measured changes in cell numbers and airway responses 1 or 3 days later. They counted the numbers of eosinophils and other white blood cells (macrophages, neutrophils, and lymphocytes) in bone marrow, blood, and bronchoalveolar lung lavage fluid. The investigators also measured important physiological responses, including bronchoconstriction. Some animals were pretreated with etanercept and monoclonal anti-IL-5, which block tumor necrosis factor-a (TNFa) and IL-5, respectively. TNFa and IL-5 blockers have been used to treat patients with asthma. A key feature of the study was a technique to distinguish which white blood cells were synthesized after exposure from those that already existed, by injecting animals with bromodeoxyuridine (BrdU). BrdU is a thymidine analogue that is incorporated into the DNA of dividing cells, serving as a marker of newly produced cells. Therefore, a snapshot can be obtained of the proportion of newly synthesized (BrdU-positive) versus pre-existing (BrdU-negative) cell types. 1. Allergic and normal animals differed in the time course of bronchoconstriction and changes in cell types after ozone exposure. In normal animals, bronchoconstriction increased substantially at day 1 but decreased by day 3 after ozone exposure. In contrast, in allergic animals bronchoconstriction remained high at day 3. Ozone also increased the percentage of newly formed, BrdU2 positive eosinophils in the bone marrow and lungs of normal but not allergic animals. 2. Pretreatment with the TNFa blocker etanercept had complex effects, which differed between normal and allergic animals. In normal animals, etanercept decreased ozone-induced new synthesis of eosinophils in the bone marrow and blocked eosinophil migration to the lung; it also increased bronchoconstriction at day 3 (relative to day 1 without etanercept). In allergic animals, etanercept had no effect on any cell type in the bone marrow or lung after exposure to ozone and did not change bronchoconstriction compared with allergic animals not treated with etanercept. Etanercept tended to increase the numbers of blood monocytes and lymphocytes in air- and ozone-exposed normal and allergic animals at day 3, but had no effect on eosinophils in blood at this time point. This was one of the few statistically significant findings in the blood of exposed animals in the study. 3. Anti-IL-5 reduced bronchoconstriction at day 3 after exposure of allergic animals to ozone. In contrast, bronchoconstriction was greatly increased in normal animals treated with anti-IL-5. Fryer and colleagues explored the airway and cellular responses in guinea pigs exposed to ozone. The HEI Review Committee, which conducted an independent review of the study, agreed that the findings supported the authors’ hypothesis (1) that exposure to ozone stimulates production of eosinophils in bone marrow, (2) that these newly formed eosinophils migrate to the lungs, and (3) that those eosinophils play a delayed but potentially beneficial role in reducing ozone-induced inflammation in the airways of healthy normal animals, but not in allergen-sensitized animals. The Committee also agreed that guinea pigs were a good model for studying responses to an allergen, because a major subtype of asthma (the high Th2 or allergic type) is associated with high levels of eosinophils in the blood. A novel finding was that the TNFa blocker etanercept decreased ozone-induced formation of eosinophils in the bone marrow and blocked eosinophil migration to the lung in normal animals. However, because injecting etanercept had little effect on eosinophils and did not decrease bronchoconstriction in allergic guinea pigs, the potential for treating patients with allergic asthma with TNFa blockers is uncertain. This is consistent with the poor performance of TNFa blockers in clinical studies of asthma treatment. Blocking the cytokine IL-5 with an anti-IL-5 antibody substantially decreased bronchoconstriction in sensitized animals. This suggests that therapies targeting IL-5 and eosinophils would be promising in at least some types of asthma. The Committee expressed caution toward experiments with cytokine blockers, both in animal models and humans, because such blockers are often not specific to a particular cell type and may differ at different sites in the body. Without further detailed confirmation of the effects of the blockers, interpreting these experiments can be challenging. The Committee concluded that the study by Fryer and colleagues raises several intriguing directions for future research, including exploring ways in which newly formed eosinophils differ from pre-existing ones, and how such findings apply to humans with allergy or asthma.

Occupational levels of radiation exposure induce surface expression of interleukin-2 receptors in stimulated human peripheral blood lymphocytes.

PubMed

Xu, Y; Greenstock, C L; Trivedi, A; Mitchel, R E

1996-05-01

Interleukin-2 (IL-2) is a cytokine responsible for a variety of immune and non-immune stimulatory and regulatory functions, including the activation and stimulation of cytotoxic cells able to recognize and kill human tumour cells and T-cell proliferation and differentiation. We show that low doses of radiation, in the range commonly received by atomic radiation workers or as a result of minor medical diagnostic procedures (0.25 to 10 mGy), stimulate the expression of IL-2 receptors (IL-2R) on the surface of peripheral blood lymphocytes (PBL) taken from normal human donors. This stimulated surface expression after in vitro irradiation is an indirect effect, resulting from the secretion into the medium of a soluble factor from the irradiated cells. This factor can also stimulate IL-2R surface expression in unirradiated cells. Consequently, radiation stimulation of IL-2R expression in a large population of PBL shows a triggered-type response rather than being proportional to dose. These results demonstrate that normal human cells can respond to doses of radiation in the range of common occupational or medical exposures. The data also demonstrate a possible defence mechanism against environmental stress by which a radiation-exposed cell can use an indirect signalling mechanism to communicate with and influence the biological processes in an unexposed cell.

Effects of chlorpyrifos on the growth and ultrastructure of green algae, Ankistrodesmus gracilis.

PubMed

Asselborn, Viviana; Fernández, Carolina; Zalocar, Yolanda; Parodi, Elisa R

2015-10-01

The effect of the organophosphorus insecticide chlorpyrifos on the growth, biovolume, and ultrastructure of the green microalga Ankistrodesmus gracilis was evaluated. Concentrations of 9.37, 18.75, 37.5, 75 and 150mgL(-1) of chlorpyrifos were assayed along with a control culture. At the end of the bioassay the ultrastructure of algal cells from control culture and from cultures exposed to 37.5 and 150mgL(-1) was observed under transmission (TEM) and scanning electron microscopy (SEM). After 24 and 48h, treatments with 75 and 150mgL(-1) inhibited the growth of A. gracilis; whereas after 72 and 96h, all the treatments except at 9.37mgL(-1) significantly affected the algae growth. The effective concentration 50 (EC50) after 96h was 22.44mgL(-1) of chlorpyrifos. After the exposure to the insecticide, an increase in the biovolume was observed, with a larger increase in cells exposed to 75 and 150mgL(-1). Radical changes were observed in the ultrastructure of cells exposed to chlorpyrifos. The insecticide affected the cell shape and the distribution of the crests in the wall. At 37.5mgL(-1) electodense bodies were observed along with an increase in the size and number of starch granules. At 150mgL(-1) such bodies occupied almost the whole cytoplasm together with lipids and remains of thylakoids. Autospores formation occurred normally at 37.5mgL(-1) while at 150mgL(-1) karyokinesis occurred, but cell-separation-phase was inhibited. The present study demonstrates that the exposure of phytoplankton to the insecticide chlorpyrifos leads to effects observed at both cellular and population level. Copyright © 2015 Elsevier Inc. All rights reserved.

Short periods of high temperature during meiosis prevent normal meiotic progression and reduce grain number in hexaploid wheat (Triticum aestivum L.).

PubMed

Draeger, Tracie; Moore, Graham

2017-09-01

Exposure of wheat to high temperatures during male meiosis prevents normal meiotic progression and reduces grain number. We define a temperature-sensitive period and link heat tolerance to chromosome 5D. This study assesses the effects of heat on meiotic progression and grain number in hexaploid wheat (Triticum aestivum L. var. Chinese Spring), defines a heat-sensitive stage and evaluates the role of chromosome 5D in heat tolerance. Plants were exposed to high temperatures (30 or 35 °C) in a controlled environment room for 20-h periods during meiosis and the premeiotic interphase just prior to meiosis. Examination of pollen mother cells (PMCs) from immature anthers immediately before and after heat treatment enabled precise identification of the developmental phases being exposed to heat. A temperature-sensitive period was defined, lasting from premeiotic interphase to late leptotene, during which heat can prevent PMCs from progressing through meiosis. PMCs exposed to 35 °C were less likely to progress than those exposed to 30 °C. Grain number per spike was reduced at 30 °C, and reduced even further at 35 °C. Chinese Spring nullisomic 5D-tetrasomic 5B (N5DT5B) plants, which lack chromosome 5D, were more susceptible to heat during premeiosis-leptotene than Chinese Spring plants with the normal (euploid) chromosome complement. The proportion of plants with PMCs progressing through meiosis after heat treatment was lower for N5DT5B plants than for euploids, but the difference was not significant. However, following exposure to 30 °C, in euploid plants grain number was reduced (though not significantly), whereas in N5DT5B plants the reduction was highly significant. After exposure to 35 °C, the reduction in grain number was highly significant for both genotypes. Implications of these findings for the breeding of thermotolerant wheat are discussed.

Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival

PubMed Central

Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

2016-01-01

During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight. PMID:27203085

CELL RESPIRATION STUDIES

PubMed Central

Daland, Geneva A.; Isaacs, Raphael

1927-01-01

1. The oxygen consumption of blood of normal individuals, when the hemoglobin is saturated with oxygen, is practically zero within the limits of experimental error of the microspirometer used. 2. The oxygen consumed in a microspirometer by the blood of patients with chronic myelogenous leucemia with a high white blood cell count, and of one with leucocytosis from sepsis, was proportional to the number of adult polymorphonuclear neutrophils in the blood. 3. No correlation could be made between the rate of oxygen absorption and the total number of white blood cells in the blood, or the total number of immature cells, or the number of red blood cells, or the amount of oxyhemoglobin. 4. The blood of patients with chronic myelogenous leucemia continued to use oxygen in the microspirometer longer than that of normal individuals, and the hemoglobin, in the leucemic bloods, became desaturated even though exposed to air. 5. In blood in which the bulk. of the cells were immature and the mature cells few, the oxygen consumption was lower than in blood in which the mature cells predominated. The rate of oxygen consumption of the immature cells was relatively low as compared to the mature. 6. The slower rate of oxygen absorption by the immature leucocytes in chronic myelogenous leucemia as compared to the mature cells, places them, in accord with Warburg's reports, in the class of the malignant tissues in this respect rather than in the group of young or embryonic cells. PMID:19869329

[The influence of EphA2 overexpression on proliferation and apoptosis of human lens epithelial cells exposed to high-concentration dexamethasone in vitro].

PubMed

Ma, C X; Zheng, G Y

2018-02-11

Objective: To construct lentiviral-mediated EphA2 overexpression vectors, transfect them into human lens epithelial cells (HLE-B3) in vitro , and investigate the effect of EphA2 gene overexpression on the proliferation and apoptosis of HLE-B3 exposed to high-concentration dexamethasone. Methods: Experimental Study. The pCDH-CMV- MCS-EF1-RFP plasmid was set up by the digestion of NOTⅠand XbaⅠ double restriction enzyme and ligation of CE ligase, and then the plasmid was transformed into DH10B cells. Seven clons were picked for enzymatic digestion and the clons with correct results were chosen for sequencing. The 293 T/17 cells were co-transfected with the pCDH-CMV-MCS-EF1-RFP-EphA2 and the packaging mixture by Lipofectamine 2000. At different multiplicities of infection (MOI=20, 50, 100, and 200) after 72-hour infection, we observed the expression of RFP and morphological changes of HLE-B3 by an inverted fluorescence microscope, and calculated the transfection efficiency through the flow cytometry. EphA2 protein expression was detected by Western blot. The following experiments were divided into four groups: normal control group (group A), EphA2 overexpression vector transfection group (group B), HLE-B3 cells exposed to dexamethasone group (group C) and EphA2 overexpression vector transfection HLE-B3 cells exposed to dexamethasone group (group D). Statistical analysis method was single factor or two factors variance analysis. Cell survival rate was detected by the Cell Counting Kit-8 assay. Cell apoptosis index was detected by Tunel. Results: Restriction enzyme digestion and sequencing indicated that EphA2 cDNA fragment was successfully inserted in the vector. The infection efficiency was up to 38.6%±3.9%, 49.2%±4.2%, 79.5%±5.5% and 80.2%±6.0% when the MOI was 20, 50, 100 and 200, respectively. There was statistically significant difference ( F= 2 600.8, P= 0.001) among the four groups and between any two groups except between the MOI=100 group and MOI=200 group ( P= 2.507) . The relative quantity of EphA2 protein of the normal control group, empty vector transfection group and EphA2 gene overexpression vector transfection group was (0.561 2±0.031 7) , (0.559 7±0.012 8) and (3.032 0±0.041 9) , respectively. There was statistically significant difference ( F= 2 646.0, P= 0.001) among the three groups and between any two groups except between the normal control group and empty vector transfection group ( P= 0.868) . The survival rate of groups A, B, C and D was 98.18%±1.85%, 122.01%±3.89%, 52.32%±1.99% and 76.18%±3.74%, respectively. There was statistically significant difference among the four groups ( F= 497.6, P= 0.001) . The survival rate of group B was greater than group A ( P= 0.001) . The survival rate of group D was greater than group C ( P= 0.001) . Tunel results showed that the apoptosis index of groups A, B, C and D was 5.4%±1.5%, 5.0%±1.3%, 23.0%±3.9% and 14.4%±2.7%, respectively. There was statistically significant difference among the four groups ( F= 397.6, P= 0.001) . The apoptosis index of group B was lower than group A, but there was no statistically significant difference between them ( P= 0.415) ; the apoptosis index of group D was lower than group C ( P= 0.018). Conclusions: The lentiviral vector carrying human EphA2 gene has been successfully constructed and efficiently expressed in HLE-B3 cells. EphA2 gene overexpression could increase the HLE-B3 cell survival rate and protect HLE-B3 cells from high-concentration dexamethasone-induced reduction of the cell survival rate. EphA2 gene overexpression could protect HLE-B3 cells from high-concentration dexamethasone-induced apoptosis, but it has no remarkable effect on apoptosis of HLE-B3 cells under physiological conditions. (Chin J Ophthalmol, 2018, 54: 125-132) .

Regionally distinct responses of microglia and glial progenitor cells to whole brain irradiation in adult and aging rats.

PubMed

Hua, Kun; Schindler, Matthew K; McQuail, Joseph A; Forbes, M Elizabeth; Riddle, David R

2012-01-01

Radiation therapy has proven efficacy for treating brain tumors and metastases. Higher doses and larger treatment fields increase the probability of eliminating neoplasms and preventing reoccurrence, but dose and field are limited by damage to normal tissues. Normal tissue injury is greatest during development and in populations of proliferating cells but also occurs in adults and older individuals and in non-proliferative cell populations. To better understand radiation-induced normal tissue injury and how it may be affected by aging, we exposed young adult, middle-aged, and old rats to 10 Gy of whole brain irradiation and assessed in gray- and white matter the responses of microglia, the primary cellular mediators of radiation-induced neuroinflammation, and oligodendrocyte precursor cells, the largest population of proliferating cells in the adult brain. We found that aging and/or irradiation caused only a few microglia to transition to the classically "activated" phenotype, e.g., enlarged cell body, few processes, and markers of phagocytosis, that is seen following more damaging neural insults. Microglial changes in response to aging and irradiation were relatively modest and three markers of reactivity - morphology, proliferation, and expression of the lysosomal marker CD68- were regulated largely independently within individual cells. Proliferation of oligodendrocyte precursors did not appear to be altered during normal aging but increased following irradiation. The impacts of irradiation and aging on both microglia and oligodendrocyte precursors were heterogeneous between white- and gray matter and among regions of gray matter, indicating that there are regional regulators of the neural response to brain irradiation. By several measures, the CA3 region of the hippocampus appeared to be differentially sensitive to effects of aging and irradiation. The changes assessed here likely contribute to injury following inflammatory challenges like brain irradiation and represent important end-points for analysis in studies of therapeutic strategies to protect patients from neural dysfunction.

Long-Term Fructose Intake Increases Adipogenic Potential: Evidence of Direct Effects of Fructose on Adipocyte Precursor Cells

PubMed Central

Zubiría, María Guillermina; Alzamendi, Ana; Moreno, Griselda; Rey, María Amanda; Spinedi, Eduardo; Giovambattista, Andrés

2016-01-01

We have previously addressed that fructose rich diet (FRD) intake for three weeks increases the adipogenic potential of stromal vascular fraction cells from the retroperitoneal adipose tissue (RPAT). We have now evaluated the effect of prolonged FRD intake (eight weeks) on metabolic parameters, number of adipocyte precursor cells (APCs) and in vitro adipogenic potential from control (CTR) and FRD adult male rats. Additionally, we have examined the direct fructose effects on the adipogenic capacity of normal APCs. FRD fed rats had increased plasma levels of insulin, triglyceride and leptin, and RPAT mass and adipocyte size. FACS studies showed higher APCs number and adipogenic potential in FRD RPAT pads; data is supported by high mRNA levels of competency markers: PPARγ2 and Zfp423. Complementary in vitro experiments indicate that fructose-exposed normal APCs displayed an overall increased adipogenic capacity. We conclude that the RPAT mass expansion observed in eight week-FRD fed rats depends on combined accelerated adipogenesis and adipocyte hypertrophy, partially due to a direct effect of fructose on APCs. PMID:27049396

Long-Term Fructose Intake Increases Adipogenic Potential: Evidence of Direct Effects of Fructose on Adipocyte Precursor Cells.

PubMed

Zubiría, María Guillermina; Alzamendi, Ana; Moreno, Griselda; Rey, María Amanda; Spinedi, Eduardo; Giovambattista, Andrés

2016-04-02

We have previously addressed that fructose rich diet (FRD) intake for three weeks increases the adipogenic potential of stromal vascular fraction cells from the retroperitoneal adipose tissue (RPAT). We have now evaluated the effect of prolonged FRD intake (eight weeks) on metabolic parameters, number of adipocyte precursor cells (APCs) and in vitro adipogenic potential from control (CTR) and FRD adult male rats. Additionally, we have examined the direct fructose effects on the adipogenic capacity of normal APCs. FRD fed rats had increased plasma levels of insulin, triglyceride and leptin, and RPAT mass and adipocyte size. FACS studies showed higher APCs number and adipogenic potential in FRD RPAT pads; data is supported by high mRNA levels of competency markers: PPARγ2 and Zfp423. Complementary in vitro experiments indicate that fructose-exposed normal APCs displayed an overall increased adipogenic capacity. We conclude that the RPAT mass expansion observed in eight week-FRD fed rats depends on combined accelerated adipogenesis and adipocyte hypertrophy, partially due to a direct effect of fructose on APCs.

Effect of mitomycin C on keloid fibroblasts: an in vitro study.

PubMed

Simman, Richard; Alani, Hashim; Williams, Frances

2003-01-01

Keloids are the result of aberrant wound healing of human skin after dermal injury. Therapeutic options include excision followed by radiation therapy, steroid injection, and compression with silicone sheets among others. Local invasion and recurrence after excision has provoked interest in treating keloids as neoplasms. The purpose of this study was to determine the effect of mitomycin C (MMC) on keloid fibroblasts. Keloid fibroblasts obtained from five different patients were exposed to MMC. A control group of normal and keloid cells was treated with phosphate buffered saline only. Contrast microscopy showed a decrease of fibroblast density during the 3 weeks after exposure for normal and keloid fibroblasts relative to untreated fibroblasts. This was confirmed by total cell counts ( = 0.1) and measurement of DNA synthesis. By the third week, there was a recovery in DNA synthesis and increased cell count for some of the treated fibroblasts. We concluded that at an appropriate concentration, MMC shows proliferation of keloid fibroblasts in vitro for a period of 3 weeks. This agent may be considered in clinical trials after surgical excision of keloids.

Detection of DNA Damage by Space Radiation in Human Fibroblasts Flown on the International Space Station

NASA Technical Reports Server (NTRS)

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis;

Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station.

PubMed

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2017-02-01

Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37°C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37°C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space. Published by Elsevier Ltd.

Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station

NASA Astrophysics Data System (ADS)

Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2017-02-01

Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37 °C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37 °C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space.

Xenon decreases cell migration and secretion of a pro-angiogenesis factor in breast adenocarcinoma cells: comparison with sevoflurane.

PubMed

Ash, S A; Valchev, G I; Looney, M; Ni Mhathuna, A; Crowley, P D; Gallagher, H C; Buggy, D J

2014-07-01

While volatile agents have been implicated in metastasis-enhancing effects on cancer cells, the effects of xenon are unknown. We investigated xenon- and sevoflurane-mediated effects on migration and expression of angiogenesis biomarkers in human breast adenocarcinoma cells. MDA-MB-231 and MCF-7 cells were exposed to xenon 70% with O2 25%, CO2 5%; control gas containing O2 25%, CO2 5%, N2 70%; or sevoflurane 2.5 vol% administered in O2 60%, N2 37%, or control gas. Cell viability was determined by the MTT assay. Migration at 24 h was determined using the Oris™ Cell Migration Assay. Secretion of angiogenesis factors was measured using a membrane-based immunoassay array. Xenon reduced MDA-MB-231 migration to 59 (13%) after 1-h exposure (P=0.02), 64 (10%) after 3 h (P=0.01), and 71 (9%) after 5 h (P=0.04) compared with control gas, without affecting viability. Similarly, MCF-7 migration was significantly reduced at all timepoints [to 58 (12%) at 1 h, 65 (12%) at 3 h, and 65% (12%) at 5 h]. Sevoflurane did not affect migration when delivered in control gas. Glycine, an N-methyl-d-aspartate receptor co-agonist, antagonized the effects of xenon on migration. Expression of the pro-angiogenesis factor regulated on activation, normal T cell expressed and secreted (RANTES) was reduced in conditioned medium from xenon-exposed MDA-MB-231 cells compared with cells exposed to either control gas or sevoflurane [mean dot density 2.0 (0.2) compared with 3.0 (0.1) and 3.1 (0.3), respectively (P=0.02)]. Xenon, but not sevoflurane, inhibited migration in both oestrogen receptor positive and negative breast adenocarcinoma cells. Furthermore, xenon decreased release of the pro-angiogenic factor RANTES from MDA-MB-231 cells. © The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Oral epithelial stem cells – implications in normal development and cancer metastasis

PubMed Central

Papagerakis, Silvana; Pannone, Giuseppe; Zheng, Li; About, Imad; Taqi, Nawar; Nguyen, Nghia P.T.; Matossian, Margarite; McAlpin, Blake; Santoro, Angela; McHugh, Jonathan; Prince, Mark E.; Papagerakis, Petros

2014-01-01

Oral mucosa is continuously exposed to environmental forces and has to be constantly renewed. Accordingly, the oral mucosa epithelium contains a large reservoir of epithelial stem cells necessary for tissue homeostasis. Despite considerable scientific advances in stem cell behavior in a number of tissues, fewer studies have been devoted to the stem cells in the oral epithelium. Most of oral mucosa stem cells studies are focused on identifying cancer stem cells (CSC) in oral squamous cell carcinomas (OSCCs) among other head and neck cancers. OSCCs are the most prevalent epithelial tumors of the head and neck region, marked by their aggressiveness and invasiveness. Due to their highly tumorigenic properties, it has been suggested that CSC may be the critical population of cancer cells in the development of OSCC metastasis. This review presents a brief overview of epithelium stem cells with implications in oral health, and the clinical implications of the CSC concept in OSCC metastatic dissemination. PMID:24803391

Ubiquitin Ligases and Deubiquitinating Enzymes in CD4+ T Cell Effector Fate Choice and Function.

PubMed

Layman, Awo A K; Oliver, Paula M

2016-05-15

The human body is exposed to potentially pathogenic microorganisms at barrier sites such as the skin, lungs, and gastrointestinal tract. To mount an effective response against these pathogens, the immune system must recruit the right cells with effector responses that are appropriate for the task at hand. Several types of CD4(+) T cells can be recruited, including Th cells (Th1, Th2, and Th17), T follicular helper cells, and regulatory T cells. These cells help to maintain normal immune homeostasis in the face of constantly changing microbes in the environment. Because these cells differentiate from a common progenitor, the composition of their intracellular milieu of proteins changes to appropriately guide their effector function. One underappreciated process that impacts the levels and functions of effector fate-determining factors is ubiquitylation. This review details our current understanding of how ubiquitylation regulates CD4(+) T cell effector identity and function. Copyright © 2016 by The American Association of Immunologists, Inc.

Immunological monitoring of dry-cleaning shop workers--exposure to tetrachloroethylene.

PubMed

Andrýs, C; Hanovcová, I; Chýlková, V; Tejral, J; Eminger, S; Procházková, J

1997-09-01

A panel of immunological parameters has been examined in a group of dry-cleaning workers (n = 21) and in a control group of administrators (n = 16) from the same plant. The results were also compared to long-term laboratory reference values (LRV) (n = 14-311). External exposure to tetrachloroethylene (PER) was represented by TWA (8 h) values in the range 11-752 mg PER/m3. Biological monitoring showed an amount from 9 to 344 mg PER/m3 in exhaled air by the end of workshift. 1. The exposed dry-cleaning workers compared to the controls from the plant had statistically significant changes in metabolic activity of phagocytes, alpha 2-macroglobulin, C3 and C4 complement component, salivary secretory IgA, and blastic transformation test. Most of the values were within the range of normal values. 2. The exposed dry-cleaning workers had several abnormal immune parameters compared to the long-term laboratory values (LRV) especially in the alpha 2-macroglobulin, C3 and percentage of T-lymphocytes. Most of the changes, even those that were statistically significant, were still within the range of normal values, but they might be classified as trends or shifts away from normal (spontaneous blastic transformation, absolute number of phagocyting cells, coeruloplasmin, circulating immunocomplexes, serum lysozyme). 3. The non-exposed controls from the same plant showed both quantitative and qualitative differences when compared to the LRV. Changes were seen in IgG, C4, CSI and in increased spontaneous metabolic activity of leucocytes, total leucocyte count, absolute number of phagocyting cells, alpha 2-macroglobulin, prealbumin, C4, circulating immunocomplexes and serum lysozyme. 4. The distribution analysis of all results detected a large number of abnormal values in both groups, more in the at-risk group. 5. As inhalation was the main route of PER exposure it was concluded that the changes might represent aspects of the response of the respiratory immune system, mainly of the alveolar macrophages. Additional postinfection effects could not be excluded in both studied groups. Individual differences in immune reactivity as well as individual range of exposure should be taken into consideration.

Inhibited interferon-gamma but normal interleukin-3 production from rats flown on the Space Shuttle

NASA Technical Reports Server (NTRS)

Gould, Cheryl L.; Lyte, Mark; Williams, Joann; Mandel, Adrian D.; Sonnenfeld, Gerald

1987-01-01

Rats were flown on Space Shuttle SL-3 for one week. When spleen cells were removed from these rats and challenged with concanavalin-A, interferon-gamma production was severely inhibited, while interleukin-3 production was unaffected compared to ground-based control rats. These data indicate that there is a defect in interferon-gamma production in rats that have been exposed to spaceflight. This defect could contribute to, and be one reason for, immunosuppression observed after spaceflight.

Low-intensity vibrations normalize adipogenesis-induced morphological and molecular changes of adult mesenchymal stem cells.

PubMed

Baskan, Oznur; Mese, Gulistan; Ozcivici, Engin

2017-02-01

Bone marrow mesenchymal stem cells that are committed to adipogenesis were exposed daily to high-frequency low-intensity mechanical vibrations to understand molecular, morphological and ultrastructural adaptations to mechanical signals during adipogenesis. D1-ORL-UVA mouse bone marrow mesenchymal stem cells were cultured with either growth or adipogenic medium for 1 week. Low-intensity vibration signals (15 min/day, 90 Hz, 0.1 g) were applied to one group of adipogenic cells, while the other adipogenic group served as a sham control. Cellular viability, lipid accumulation, ultrastructure and morphology were determined with MTT, Oil-Red-O staining, phalloidin staining and atomic force microscopy. Semiquantitative reverse transcription polymerase chain reaction showed expression profile of the genes responsible for adipogenesis and ultrastructure of cells. Low-intensity vibration signals increased viability of the cells in adipogenic culture that was reduced significantly compared to quiescent controls. Low-intensity vibration signals also normalized the effects of adipogenic condition on cell morphology, including area, perimeter, circularization and actin cytoskeleton. Furthermore, low-intensity vibration signals reduced the expression of some adipogenic markers significantly. Mesenchymal stem cells are sensitive and responsive to mechanical loads, but debilitating conditions such as aging or obesity may steer mesenchymal stem cells toward adipogenesis. Here, daily application of low-intensity vibration signals partially neutralized the effects of adipogenic induction on mesenchymal stem cells, suggesting that these signals may provide an alternative and/or complementary option to reduce fat deposition.

CD4+ T cell expression of MyD88 is essential for normal resolution of Chlamydia muridarum genital tract infection.

PubMed

Frazer, Lauren C; Sullivan, Jeanne E; Zurenski, Matthew A; Mintus, Margaret; Tomasak, Tammy E; Prantner, Daniel; Nagarajan, Uma M; Darville, Toni

2013-10-15

Resolution of Chlamydia genital tract infection is delayed in the absence of MyD88. In these studies, we first used bone marrow chimeras to demonstrate a requirement for MyD88 expression by hematopoietic cells in the presence of a wild-type epithelium. Using mixed bone marrow chimeras we then determined that MyD88 expression was specifically required in the adaptive immune compartment. Furthermore, adoptive transfer experiments revealed that CD4(+) T cell expression of MyD88 was necessary for normal resolution of genital tract infection. This requirement was associated with a reduced ability of MyD88(-/-)CD4(+) T cells to accumulate in the draining lymph nodes and genital tract when exposed to the same inflammatory milieu as wild-type CD4(+) T cells. We also demonstrated that the impaired infection control we observed in the absence of MyD88 could not be recapitulated by deficiencies in TLR or IL-1R signaling. In vitro, we detected an increased frequency of apoptotic MyD88(-/-)CD4(+) T cells upon activation in the absence of exogenous ligands for receptors upstream of MyD88. These data reveal an intrinsic requirement for MyD88 in CD4(+) T cells during Chlamydia infection and indicate that the importance of MyD88 extends beyond innate immune responses by directly influencing adaptive immunity.

Effect of tetracycline and UV radiation on melanization and antioxidant status of melanocytes.

PubMed

Rok, Jakub; Buszman, Ewa; Delijewski, Marcin; Otręba, Michał; Beberok, Artur; Wrześniok, Dorota

2015-07-01

Tetracycline is a semisynthetic antibiotic and is used in several types of infections against both gram-positive and gram-negative bacteria. This therapy is often associated with phototoxic reactions that occur after exposure to UV radiation and lead to photo-onycholysis, pseudoporphyria, solar urticaria and the fixed drug eruption in the skin. The phototoxic reactions may be related to the melanin content which, on one side may bind drugs - leading to their accumulation, and on the other side, they have photoprotective and antioxidant properties. In this study the effect of tetracycline and UVA irradiation on cell viability, biosynthesis of melanin and antioxidant defense system in cultured normal human epidermal melanocytes (HEMn-DP) was analyzed. The viability of the cells treated with tetracycline and exposed to UVA radiation decreased in a drug concentration-dependent manner. At the same time, the induction of the melanization process was observed. The significant alterations in antioxidant defense system, on the basis of changes in SOD, CAT and GPx activities, were stated. The obtained results may give explanation for the phototoxic effects of tetracycline therapy observed in skin cells exposed to UVA radiation. Copyright © 2015 Elsevier B.V. All rights reserved.

Impact of organic solvents and environmental pollutants on the physiological function in petrol filling workers.

PubMed

Uzma, Nazia; Salar, B M Khaja Mohinuddin; Kumar, B Santhosh; Aziz, Nusrat; David, M Anthony; Reddy, V Devender

2008-09-01

Long term exposure to solvents and air pollutants can lead to deleterious effects on respiratory, haematological and thyroid functioning. The aim of this study was to investigate whether chronic exposure to solvents like benzene and pollutants like carbon monoxide in petrol filling workers had adverse effect on blood parameters, thyroid and respiratory functions. The study group consisted of 42 healthy, non-smoker petrol filling workers, aged 20-50 years with work (exposure) duration from 2-15 years while 36 healthy subjects of the same age group served as controls. Physical examination and measurement of pulmonary functions by portable electronic spirometer were performed. Complete blood pictures (CBP) were determined by normal haematology lab procedure and hormones by Chemiluminescence immunoassay (CLIA) light absorption techniques. There was a significant decrease in the lung volumes and capacities; the restrictive pattern was more prevalent in the workers when compared with the control groups. But in the workers exposed for long period (more than 10 years) the restrictive pattern was changed to mixed pattern. A significant increase in haemoglobin (Hb) (>16 mg %) and red blood cells (RBC) (5.4 million cells/mm3) were observed in workers with longer period of exposure when compared with the control subjects (14.483 mg% and 4.83 million cells/mm3 for Hb and RBC respectively). White blood cell count except eosinophils and platelets were significantly lower in workers compared to controls. Marked increase in the tetra iodothyroinine (T4), free thyroxine (T4F) level and significant decrease in thyroid stimulating hormones (TSH), and tri-iodothyronine (T3) were observed between long term exposed and non-exposed groups. Till now researchers focused only on the effect of solvents in workers professionally exposed to solvents without considering the effect of concomittant air pollution. The result obtained from present study indicates that there is a significant toxic effect of solvents and air pollutants on workers exposed for longer duration. Improved detection and prevention technologies are needed to answer environmentally related health questions for petrol filling workers.

Electric Signals Regulate the Directional Migration of Oligodendrocyte Progenitor Cells (OPCs) via β1 Integrin.

PubMed

Zhu, Bangfu; Nicholls, Matthew; Gu, Yu; Zhang, Gaofeng; Zhao, Chao; Franklin, Robin J M; Song, Bing

2016-11-22

The guided migration of neural cells is essential for repair in the central nervous system (CNS). Oligodendrocyte progenitor cells (OPCs) will normally migrate towards an injury site to re-sheath demyelinated axons; however the mechanisms underlying this process are not well understood. Endogenous electric fields (EFs) are known to influence cell migration in vivo, and have been utilised in this study to direct the migration of OPCs isolated from neonatal Sprague-Dawley rats. The OPCs were exposed to physiological levels of electrical stimulation, and displayed a marked electrotactic response that was dependent on β1 integrin, one of the key subunits of integrin receptors. We also observed that F-actin, an important component of the cytoskeleton, was re-distributed towards the leading edge of the migrating cells, and that this asymmetric rearrangement was associated with β1 integrin function.

ERK and p38 Upregulation versus Bcl-6 Downregulation in Rat Kidney Epithelial Cells Exposed to Prolonged Hypoxia.

PubMed

Luo, Fengbao; Shi, Jian; Shi, Qianqian; He, Xiaozhou; Xia, Ying

2017-08-01

Hypoxia is a common cause of kidney injury and a major issue in kidney transplantation. Mitogen-activated protein kinases (MAPKs) are involved in the cellular response to hypoxia, but the precise roles of MAPKs in renal cell reactions to hypoxic stress are not well known yet. This work was conducted to investigate the regulation of extracellular signal-regulated kinase-1 and -2 (ERK1/2) and p38 and their signaling-relevant molecules in kidney epithelial cells exposed to prolonged hypoxia. Rat kidney epithelial cells Normal Rat Kidney (NRK)-52E were exposed to hypoxic conditions (1% O 2 ) for 24 to 72 h. Cell morphology was examined by light microscopy, and cell viability was checked by 3-[4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxypheny]-2-[4-sulfophenyl]-2H-tetrazolium (MTS). The expression of ERK1/2 and p38 MAPK, as well as their signaling-related molecules, was measured by Western blot and real-time polymerase chain (RT-PCR) reaction. At the 1% oxygen level, cell morphology had no appreciable changes compared to the control up to 72 h of exposure under light microscopy, whereas the results of MTS showed a slight but significant reduction in cell viability after 72 h of hypoxia. On the other hand, ERK1/2 and p38 phosphorylation remarkably increased in these cells after 24 to 72 h of hypoxia. In sharp contrast, the expression of transcription factor B-cell lymphoma 6 (Bcl-6) was significantly downregulated in response to hypoxic stress. Other intracellular molecules relevant to the ERK1/2 and p38 signaling pathway, such as protein kinase A, protein kinase C, Bcl-2, nuclear factor erythroid 2-related factor 2, tristetraprolin, and interleukin-10(IL-10), had no significant alterations after 24 to 72 h of hypoxic exposure. We conclude that hypoxic stress increases the phosphorylation of both ERK1/2 and p38 but decreases the level of Bcl-6 in rat kidney epithelial cells.

Immunohistochemical, morphological and histometrical analyses of follicular development in Astyanax bimaculatus (Teleostei: Characidae) exposed to an organochlorine insecticide.

PubMed

Marcon, Lucas; Thomé, Ralph Gruppi; Mounteer, Ann Honor; Bazzoli, Nilo; Rizzo, Elizete; Benjamin, Laércio Dos Anjos

2017-09-01

Thiodan ® is an organochlorine insecticide used in agriculture that can reach aquatic ecosystems where it can affect fish reproduction. This research aimed to evaluate follicular development and the expression of integrin β1, collagen type IV and caspase 3 by morphological, histometrical and immunohistochemical analyses of Astyanax bimaculatus exposed to Thiodan ® . Treatments included three sublethal concentrations of Thiodan ® (1.15, 2.30, and 5.60μgL -1 ) for 96h and a control without the insecticide. Mature females with ovaries in advanced follicular development were chosen for study (average weight: 11.52 ± 2.0g; average total length: 9.12 ± 0.64cm). The follicles of A. bimaculatus exhibited normal morphology, while the diameters of secondary follicles showed an increase (P< 0.05) in all concentrations when compared to the control group; a characteristic of follicles undergoing the initial stages of intoxication. Immunohistochemical analysis revealed secondary follicles with greater expression of integrin β1 and collagen type IV in cytoplasm of follicular cells than in the primary follicles in all treatments and in the control. Immunolocalization of caspase 3 was detected in follicular cells during secondary development in all tested concentrations of Thiodan ® and the control. These analyses demonstrate positive immunolocalization throughout the course of follicular development, even in fish exposed to varying concentrations of Thiodan ® for 96h, demonstrating that follicular cells retain their physiological integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

[Effects of propranolol on oxygen-induced retinal neovascularization in mouse].

PubMed

Huang, Xuerong; Wang, Yajuan; Yang, Guangran; Yang, Zixin; Zhang, Jingshang

2016-02-01

To investigate whether propranolol application as collyrium or intraperitoneal (IP) injection can promote the recovery of oxygen-induced retinopathy (OIR). Thirty-six 7-day-old mice were divided into the following 6 groups: normal control, propranolol eye drops, propranolol IP injection, eye drops negative control, IP injection negative control, and pathological model with 6 mice in each. In a typical model of OIR, litters of mice pups with their nursing mothers were exposed to an infant incubator to high oxygen concentration (75 ± 5)% between postnatal day (PD) 7 and PD12, prior to returning to room air. Two routes of propranolol treatment were assessed from PD12 to PD17: IP injection and eye drop, with doses 2 mg/(kg·time), three times a day. Another three groups were given citric acid buffer eye drops, IP injection of citric acid buffer, and negative control were not treated with any drug. Neonatal mice fed in normal conditions served as normal control. Mice were sacrificed at PD17 to evaluate the morphological changes of retinal vessels by fluorescein isothiocyanate-dextran perfusion and retinal whole mount. The retinal neovascularization was evaluated by counting the number of nuclei of the endothelial cell breaking through the internal limiting membrane (ILM). Compared with the oxygen-exposed group, the branches of retinal vessels went normal with a less un-perfused area in the propranolol eye drops and propranolol IP injection groups [(38.9 ± 9.9)% and (5.6 ± 2.3)% vs. (16.2 ± 10.0)% and (2.2 ± 0.8)%, (25.9 ± 5.0)% and (2.1 ± 2.7)%, F=36.12 and 14.55, P both<0.001]. The number of nuclei of endothelial cells breaking through the ILM on the retinal cross-section in the propranolol eye drops group decreased (14.2 ± 5.1) per slide, which was less than that in the oxygen-exposed group (49.1 ± 8.9) per slide and the propranolol IP injection group (18.0 ± 5.9) per slide; it was also less than that in the eye drops negative control group (47.4 ± 8.1) per slide (F=187.60, P<0.05). Moreover, the number of nuclei of endothelial cells breaking through the ILM on the retinal cross-section in the propranolol IP injection group was less than that in the IP injection negative control group (49.9 ± 7.1) per slide (P<0.05). Propranolol could effectively inhibit the formation of retinal neovascularization in mice; the eye drops was more effective than the IP injection.

A Role for Fibroblasts in Mediating the Effects of Tobacco-Induced Epithelial Cell Growth and Invasion

PubMed Central

Coppe, Jean-Philippe; Boysen, Megan; Ho Sun, Chung; Wong, Brian J.F.; Kang, Mo K.; Park, No-Hee; Desprez, Pierre-Yves; Campisi, Judith; Krtolica, Ana

2009-01-01

Cigarette smoke and smokeless tobacco extracts contain multiple carcinogenic compounds, but little is known about the mechanisms by which tumors develop and progress upon chronic exposure to carcinogens such as those present in tobacco products. Here, we examine the effects of smokeless tobacco extracts on human oral fibroblasts. We show that smokeless tobacco extracts elevated the levels of intracellular reactive oxygen, oxidative DNA damage, and DNA double-strand breaks in a dose-dependent manner. Extended exposure to extracts induced fibroblasts to undergo a senescence-like growth arrest, with striking accompanying changes in the secretory phenotype. Using cocultures of smokeless tobacco extracts–exposed fibroblasts and immortalized but nontumorigenic keratinocytes, we further show that factors secreted by extracts-modified fibroblasts increase the proliferation and invasiveness of partially transformed epithelial cells, but not their normal counterparts. In addition, smokeless tobacco extracts–exposed fibroblasts caused partially transformed keratinocytes to lose the expression of E-cadherin and ZO-1, as well as involucrin, changes that are indicative of compromised epithelial function and commonly associated with malignant progression. Together, our results suggest that fibroblasts may contribute to tumorigenesis indirectly by increasing epithelial cell aggressiveness. Thus, tobacco may not only initiate mutagenic changes in epithelial cells but also promote the growth and invasion of mutant cells by creating a procarcinogenic stromal environment. PMID:18644973

Oxidative stress response in SH-SY5Y cells exposed to short-term 1800 MHz radiofrequency radiation.

PubMed

Marjanovic Cermak, Ana Marija; Pavicic, Ivan; Trosic, Ivancica

2018-01-28

The exact mechanism that could explain the effects of radiofrequency (RF) radiation exposure at non-thermal level is still unknown. Increasing evidence suggests a possible involvement of reactive oxygen species (ROS) and development of oxidative stress. To test the proposed hypothesis, human neuroblastoma cells (SH-SY5Y) were exposed to 1800 MHz short-term RF exposure for 10, 30 and 60 minutes. Electric field strength within Gigahertz Transverse Electromagnetic cell (GTEM) was 30 V m -1 and specific absorption rate (SAR) was calculated to be 1.6 W kg -1 . Cellular viability was measured by MTT assay and level of ROS was determined by fluorescent probe 2',7'-dichlorofluorescin diacetate. Concentrations of malondialdehyde and protein carbonyls were used to assess lipid and protein oxidative damage and antioxidant activity was evaluated by measuring concentrations of total glutathione (GSH). After radiation exposure, viability of irradiated cells remained within normal physiological values. Significantly higher ROS level was observed for every radiation exposure time. After 60 min of exposure, the applied radiation caused significant lipid and protein damage. The highest GSH concentration was detected after 10 minute-exposure. The results of our study showed enhanced susceptibility of SH-SY5Y cells for development of oxidative stress even after short-term RF exposure.

Synchrotron based infrared imaging and spectroscopy via focal plane array on live fibroblasts in D2O enriched medium

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

Quaroni, Luca; Zlateva, Theodora; Sarafimov, Blagoj

2014-03-26

We tested the viability of using synchrotron based infrared imaging to study biochemical processes inside living cells. As a model system, we studied fibroblast cells exposed to a medium highly enriched with D2O. We could show that the experimental technique allows us to reproduce at the cellular level measurements that are normally performed on purified biological molecules. We can obtain information about lipid conformation and distribution, kinetics of hydrogen/deuterium exchange, and the formation of concentration gradients of H and O isotopes in water that are associated with cell metabolism. The implementation of the full field technique in a sequential imagingmore » format gives a description of cellular biochemistry and biophysics that contains both spatial and temporal information.« less

Cigarette smoke induced urocystic epithelial mesenchymal transition via MAPK pathways.

PubMed

Yu, Dexin; Geng, Hao; Liu, Zhiqi; Zhao, Li; Liang, Zhaofeng; Zhang, Zhiqiang; Xie, Dongdong; Wang, Yi; Zhang, Tao; Min, Jie; Zhong, Caiyun

2017-01-31

Cigarette smoke has been shown to be a major risk factor for bladder cancer. Epithelial-mesenchymal transition (EMT) is a crucial process in cancer development. The role of MAPK pathways in regulating cigarette smoke-triggered urocystic EMT remains to be elucidated. Human normal urothelial cells and BALB/c mice were used as in vitro and in vivo cigarette smoke exposure models. Exposure of human normal urothelial cells to cigarette smoke induced morphological change, enhanced migratory and invasive capacities, reduced epithelial marker expression and increased mesenchymal marker expression, along with the activation of MAPK pathways. Moreover, we revealed that ERK1/2 and p38 inhibitors, but rather JNK inhibitor, effectively attenuated cigarette smoke-induced urocystic EMT. Importantly, the regulatory function of ERK1/2 and p38 pathways in cigarette smoke-triggered urocystic EMT was further confirmed in mice exposed to CS for 12 weeks. These findings could provide new insight into the molecular mechanisms of cigarette smoke-associated bladder cancer development as well as its potential intervention.

Effects of stripped oil shale retort water on fishes, birds, and mammals

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

Nystrom, R.R.

1983-01-01

Golden hamsters (Mesocricetus auratus Water), coturnix quail (Coturnix coturnix Teminck and Schlegal), fathead minnows (Pimphales promelas Rafinesque), and rainbow trout (Salmo gairdneri Richardson) were subjected to various exposures of stripped oil shale retort water (SRW). Chronic low-level exposures of all experimental animals to SRW revealed no adverse histological effects attributable to SRW. Also, production and development of second generation fathead minnows and coturnix quail exposed to SRW was normal. Subacute exposure of rainbow trout to SRW produced ultrastructural changes detected by transmission, scanning, and freeze fracture electron microscopy) in the gill, liver, and kidney tissues. The gills showed a swellingmore » of secondary lamellae, disorganization of normal tissue architecture, and sloughing of respiratory cells. The liver contained lamellar bodies not seen in the controls. Relatively large, electron dense, membrane-bounded deposits were present in proximal tubule cells of the kidney. Sodium arsenite (a significant component of SRW) was shown to cause swelling of granular endosplasmic reticulum in quail liver tissue with an acute exposure. This effect could be related to the fact that arsenic inhibits ATP production, which would decrease the ability of the sodium pumps to maintain a normal osmotic balance.« less

Lactic acidosis switches cancer cells from aerobic glycolysis back to dominant oxidative phosphorylation

PubMed Central

Wu, Hao; Ying, Minfeng; Hu, Xun

2016-01-01

While transformation of normal cells to cancer cells is accompanied with a switch from oxidative phosphorylation (OXPHOS) to aerobic glycolysis, it is interesting to ask if cancer cells can revert from Warburg effect to OXPHOS. Our previous works suggested that cancer cells reverted to OXPHOS, when they were exposed to lactic acidosis, a common factor in tumor environment. However, the conclusion cannot be drawn unless ATP output from glycolysis and OXPHOS is quantitatively determined. Here we quantitatively measured ATP generation from glycolysis and OXPHOS in 9 randomly selected cancer cell lines. Without lactic acidosis, glycolysis and OXPHOS generated 23.7% − 52.2 % and 47.8% − 76.3% of total ATP, respectively; with lactic acidosis (20 mM lactate with pH 6.7), glycolysis and OXPHOS provided 5.7% − 13.4% and 86.6% − 94.3% of total ATP. We concluded that cancer cells under lactic acidosis reverted from Warburg effect to OXPHOS phenotype. PMID:27259254

Single-cell and subcellular pharmacokinetic imaging allows insight into drug action in vivo.

PubMed

Thurber, Greg M; Yang, Katy S; Reiner, Thomas; Kohler, Rainer H; Sorger, Peter; Mitchison, Tim; Weissleder, Ralph

2013-01-01

Pharmacokinetic analysis at the organ level provides insight into how drugs distribute throughout the body, but cannot explain how drugs work at the cellular level. Here we demonstrate in vivo single-cell pharmacokinetic imaging of PARP-1 inhibitors and model drug behaviour under varying conditions. We visualize intracellular kinetics of the PARP-1 inhibitor distribution in real time, showing that PARP-1 inhibitors reach their cellular target compartment, the nucleus, within minutes in vivo both in cancer and normal cells in various cancer models. We also use these data to validate predictive finite element modelling. Our theoretical and experimental data indicate that tumour cells are exposed to sufficiently high PARP-1 inhibitor concentrations in vivo and suggest that drug inefficiency is likely related to proteomic heterogeneity or insensitivity of cancer cells to DNA-repair inhibition. This suggests that single-cell pharmacokinetic imaging and derived modelling improve our understanding of drug action at single-cell resolution in vivo.

Caspase Activity Is Required for Engulfment of Apoptotic Cells

PubMed Central

Shklyar, Boris; Levy-Adam, Flonia; Mishnaevski, Ketty

2013-01-01

Clearance of apoptotic cells by phagocytic neighbors is crucial for normal development of multicellular organisms. However, how phagocytes discriminate between healthy and dying cells remains poorly understood. We focus on glial phagocytosis of apoptotic neurons during development of the Drosophila central nervous system. We identified phosphatidylserine (PS) as a ligand on apoptotic cells for the phagocytic receptor Six Microns Under (SIMU) and report that PS alone is not sufficient for engulfment. Our data reveal that, additionally to PS exposure, caspase activity is required for clearance of apoptotic cells by phagocytes. Here we demonstrate that SIMU recognizes and binds PS on apoptotic cells through its N-terminal EMILIN (EMI), Nimrod 1 (NIM1), and NIM2 repeats, whereas the C-terminal NIM3 and NIM4 repeats control SIMU affinity to PS. Based on the structure-function analysis of SIMU, we discovered a novel mechanism of internal inhibition responsible for differential affinities of SIMU to its ligand which might prevent elimination of living cells exposing PS on their surfaces. PMID:23754750

The Potential Protective Effects of 2-aminoethyl Diphenylborinate against Inner Ear Acoustic Trauma: Experimental Study Using Transmission and Scanning Electron Microscopy.

PubMed

Kaymakçı, Mustafa; Acar, Mustafa; Burukoglu, Dilek; Kutlu, Hatice Mehtap; Shojaolsadati, Paria; Cingi, Cemal; Bayar Muluk, Nuray

2015-04-01

In this prospective experimental study, we investigated the preventive effects of 2-aminoethyl diphenylborinate (2-APB) in rats exposed to acoustic trauma (AT). Light microscopic, transmission electron microscopic (TEM), and scanning electron microscopic (SEM) examinations were performed. Eighteen healthy Wistar albino rats were divided into the following three groups: groups 1 (control), 2 (AT), and 3 (AT+APB). The rats in groups 2 and 3 were exposed to AT; in group 3 rats, 2-APB at 2 mg/kg was also administered, initially transperitoneally, after 10 min. During the light microscopic, TEM, and SEM examinations, the structures of the cochlear hair cells, stereocilia, and Deiter's cells were normal in the control group. In the AT group, the organ of Corti and proximate structures were damaged according to the light microscopic examination. During the TEM examination, intense cellular damage and stereocilia loss were detected, while during the SEM examination, extensive damage and stereocilia loss were observed. Decreased damage with preserved cochlear structure was detected during the light microscopic examination in the AT+APB group than in the AT group. During the TEM and SEM examinations, although stereocilia loss occurred in the AT+APB group, near-normal cell, cilia, and tectorial membrane structures were also observed in the AT+APB group compared with the AT group. 2-APB may have protective effects against AT damage of the cochlea. The main mechanism underlying this effect is the inhibition of the vasoconstriction of the cochlear spiral modiolar artery, thereby improving cochlear blood flow. We conclude that 2-APB may also be effective if used immediately following AT.

Central auditory processing effects induced by solvent exposure.

PubMed

Fuente, Adrian; McPherson, Bradley

2007-01-01

Various studies have demonstrated that organic solvent exposure may induce auditory damage. Studies conducted in workers occupationally exposed to solvents suggest, on the one hand, poorer hearing thresholds than in matched non-exposed workers, and on the other hand, central auditory damage due to solvent exposure. Taking into account the potential auditory damage induced by solvent exposure due to the neurotoxic properties of such substances, the present research aimed at studying the possible auditory processing disorder (APD), and possible hearing difficulties in daily life listening situations that solvent-exposed workers may acquire. Fifty workers exposed to a mixture of organic solvents (xylene, toluene, methyl ethyl ketone) and 50 non-exposed workers matched by age, gender and education were assessed. Only subjects with no history of ear infections, high blood pressure, kidney failure, metabolic and neurological diseases, or alcoholism were selected. The subjects had either normal hearing or sensorineural hearing loss, and normal tympanometric results. Hearing-in-noise (HINT), dichotic digit (DD), filtered speech (FS), pitch pattern sequence (PPS), and random gap detection (RGD) tests were carried out in the exposed and non-exposed groups. A self-report inventory of each subject's performance in daily life listening situations, the Amsterdam Inventory for Auditory Disability and Handicap, was also administered. Significant threshold differences between exposed and non-exposed workers were found at some of the hearing test frequencies, for both ears. However, exposed workers still presented normal hearing thresholds as a group (equal or better than 20 dB HL). Also, for the HINT, DD, PPS, FS and RGD tests, non-exposed workers obtained better results than exposed workers. Finally, solvent-exposed workers reported significantly more hearing complaints in daily life listening situations than non-exposed workers. It is concluded that subjects exposed to solvents may acquire an APD and thus the sole use of pure-tone audiometry is insufficient to assess hearing in solvent-exposed populations.

Phospho-Bcl-xL(Ser62) influences spindle assembly and chromosome segregation during mitosis.

PubMed

Wang, Jianfang; Beauchemin, Myriam; Bertrand, Richard

2014-01-01

Functional analysis of a series of phosphorylation mutants reveals that Bcl-xL(Ser62Ala) influences cell entry into anaphase and mitotic exit in taxol-exposed cells compared with cells expressing wild-type Bcl-xL or a series of other phosphorylation mutants, an effect that appears to be independent of its anti-apoptotic activity. During normal mitosis progression, Bcl-xL(Ser62) is strongly phosphorylated by PLK1 and MAPK14/SAPKp38α at the prometaphase, metaphase, and the anaphase boundaries, while it is de-phosphorylated at telophase and cytokinesis. Phospho-Bcl-xL(Ser62) localizes in centrosomes with γ-tubulin and in the mitotic cytosol with some spindle-assembly checkpoint signaling components, including PLK1, BubR1, and Mad2. In taxol- and nocodazole-exposed cells, phospho-Bcl-xL(Ser62) also binds to Cdc20- Mad2-, BubR1-, and Bub3-bound complexes, while Bcl-xL(Ser62Ala) does not. Silencing Bcl-xL expression and expressing the phosphorylation mutant Bcl-xL(Ser62Ala) lead to an increased number of cells harboring mitotic spindle defects including multipolar spindle, chromosome lagging and bridging, aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h. Together, the data indicate that during mitosis, Bcl-xL(Ser62) phosphorylation impacts on spindle assembly and chromosome segregation, influencing chromosome stability. Observations of mitotic cells harboring aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h were also made with cells expressing the phosphorylation mutant Bcl-xL(Ser49Ala) and dual mutant Bcl-xL(Ser49/62Ala).

Development of a dose-controlled multiculture cell exposure chamber for efficient delivery of airborne and engineered nanoparticles

NASA Astrophysics Data System (ADS)

Asimakopoulou, Akrivi; Daskalos, Emmanouil; Lewinski, Nastassja; Riediker, Michael; Papaioannou, Eleni; Konstandopoulos, Athanasios G.

2013-04-01

In order to study the various health influencing parameters related to engineered nanoparticles as well as to soot emitted by Diesel engines, there is an urgent need for appropriate sampling devices and methods for cell exposure studies that simulate the respiratory system and facilitate associated biological and toxicological tests. The objective of the present work was the further advancement of a Multiculture Exposure Chamber (MEC) into a dose-controlled system for efficient delivery of nanoparticles to cells. It was validated with various types of nanoparticles (Diesel engine soot aggregates, engineered nanoparticles for various applications) and with state-of-the-art nanoparticle measurement instrumentation to assess the local deposition of nanoparticles on the cell cultures. The dose of nanoparticles to which cell cultures are being exposed was evaluated in the normal operation of the in vitro cell culture exposure chamber based on measurements of the size specific nanoparticle collection efficiency of a cell free device. The average efficiency in delivering nanoparticles in the MEC was approximately 82%. The nanoparticle deposition was demonstrated by Transmission Electron Microscopy (TEM). Analysis and design of the MEC employs Computational Fluid Dynamics (CFD) and true to geometry representations of nanoparticles with the aim to assess the uniformity of nanoparticle deposition among the culture wells. Final testing of the dose-controlled cell exposure system was performed by exposing A549 lung cell cultures to fluorescently labeled nanoparticles. Delivery of aerosolized nanoparticles was demonstrated by visualization of the nanoparticle fluorescence in the cell cultures following exposure. Also monitored was the potential of the aerosolized nanoparticles to generate reactive oxygen species (ROS) (e.g. free radicals and peroxides generation), thus expressing the oxidative stress of the cells which can cause extensive cellular damage or damage on DNA.

Phase imaging microscopy for the diagnostics of plasma-cell interaction

NASA Astrophysics Data System (ADS)

Ohene, Yolanda; Marinov, Ilya; de Laulanié, Lucie; Dupuy, Corinne; Wattelier, Benoit; Starikovskaia, Svetlana

2015-06-01

Phase images of biological specimens were obtained by the method of Quadriwave Lateral Shearing Interferometry (QWLSI). The QWLSI technique produces, at high resolution, phase images of the cells having been exposed to a plasma treatment and enables the quantitative analysis of the changes in the surface area of the cells over time. Morphological changes in the HTori normal thyroid cells were demonstrated using this method. There was a comparison of the cell behaviour between control cells, cells treated by plasma of a nanosecond dielectric barrier discharge, including cells pre-treated by catalase, and cells treated with an equivalent amount of H2O2. The major changes in the cell membrane morphology were observed at only 5 min after the plasma treatment. The primary role of reactive oxygen species (ROS) in this degradation is suggested. Deformation and condensation of the cell nucleus were observed 2-3 h after the treatment and are supposedly related to apoptosis induction. The coupling of the phase QWLSI with immunofluorescence imaging would give a deeper insight into the mechanisms of plasma induced cell death.

Tinnitus and other auditory problems - occupational noise exposure below risk limits may cause inner ear dysfunction.

PubMed

Lindblad, Ann-Cathrine; Rosenhall, Ulf; Olofsson, Åke; Hagerman, Björn

2014-01-01

The aim of the investigation was to study if dysfunctions associated to the cochlea or its regulatory system can be found, and possibly explain hearing problems in subjects with normal or near-normal audiograms. The design was a prospective study of subjects recruited from the general population. The included subjects were persons with auditory problems who had normal, or near-normal, pure tone hearing thresholds, who could be included in one of three subgroups: teachers, Education; people working with music, Music; and people with moderate or negligible noise exposure, Other. A fourth group included people with poorer pure tone hearing thresholds and a history of severe occupational noise, Industry. Ntotal = 193. The following hearing tests were used: - pure tone audiometry with Békésy technique, - transient evoked otoacoustic emissions and distortion product otoacoustic emissions, without and with contralateral noise; - psychoacoustical modulation transfer function, - forward masking, - speech recognition in noise, - tinnitus matching. A questionnaire about occupations, noise exposure, stress/anxiety, muscular problems, medication, and heredity, was addressed to the participants. Forward masking results were significantly worse for Education and Industry than for the other groups, possibly associated to the inner hair cell area. Forward masking results were significantly correlated to louder matched tinnitus. For many subjects speech recognition in noise, left ear, did not increase in a normal way when the listening level was increased. Subjects hypersensitive to loud sound had significantly better speech recognition in noise at the lower test level than subjects not hypersensitive. Self-reported stress/anxiety was similar for all groups. In conclusion, hearing dysfunctions were found in subjects with tinnitus and other auditory problems, combined with normal or near-normal pure tone thresholds. The teachers, mostly regarded as a group exposed to noise below risk levels, had dysfunctions almost identical to those of the more exposed Industry group.

Tinnitus and Other Auditory Problems – Occupational Noise Exposure below Risk Limits May Cause Inner Ear Dysfunction

PubMed Central

Lindblad, Ann-Cathrine; Rosenhall, Ulf; Olofsson, Åke; Hagerman, Björn

2014-01-01

The aim of the investigation was to study if dysfunctions associated to the cochlea or its regulatory system can be found, and possibly explain hearing problems in subjects with normal or near-normal audiograms. The design was a prospective study of subjects recruited from the general population. The included subjects were persons with auditory problems who had normal, or near-normal, pure tone hearing thresholds, who could be included in one of three subgroups: teachers, Education; people working with music, Music; and people with moderate or negligible noise exposure, Other. A fourth group included people with poorer pure tone hearing thresholds and a history of severe occupational noise, Industry. Ntotal = 193. The following hearing tests were used: − pure tone audiometry with Békésy technique, − transient evoked otoacoustic emissions and distortion product otoacoustic emissions, without and with contralateral noise; − psychoacoustical modulation transfer function, − forward masking, − speech recognition in noise, − tinnitus matching. A questionnaire about occupations, noise exposure, stress/anxiety, muscular problems, medication, and heredity, was addressed to the participants. Forward masking results were significantly worse for Education and Industry than for the other groups, possibly associated to the inner hair cell area. Forward masking results were significantly correlated to louder matched tinnitus. For many subjects speech recognition in noise, left ear, did not increase in a normal way when the listening level was increased. Subjects hypersensitive to loud sound had significantly better speech recognition in noise at the lower test level than subjects not hypersensitive. Self-reported stress/anxiety was similar for all groups. In conclusion, hearing dysfunctions were found in subjects with tinnitus and other auditory problems, combined with normal or near-normal pure tone thresholds. The teachers, mostly regarded as a group exposed to noise below risk levels, had dysfunctions almost identical to those of the more exposed Industry group. PMID:24827149

[Effect of different oxygen concentrations on biological properties of bone marrow hematopoietic stem cells of mice].

PubMed

Ma, Yi-Ran; Ren, Si-Hua; He, Yu-Xin; Wang, Lin-Lin; Jin, Li; Hao, Yi-Wen

2012-10-01

This study purposed to investigate the effects of different oxygen concentrations and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and their possible mechanisms through simulating oxygen environment to which the peripheral blood HSC are subjected in peripheral blood HSCT. The proliferation ability, cell cycle, directed differentiation ability, ROS level and hematopoietic reconstitution ability of Lin(-)c-kit(+)Sca-1(+) BMHSC were detected by using in vitro amplification test, directional differentiation test, cell cycle analysis, ROS assay and transplantation of Lin(-)c-kit(+)Sca-1(+) HSC from sublethally irradiated mice respectively. The results showed that oxygen concentrations lower than normal oxygen concentration, especially in hypoxic oxygen environment, could reduce ROS generation and amplify more primitive CD34(+)AC133(+) HSC and active CD34(+) HSC, and maintain more stem cells in the G(0)/G(1) phase, which is more helpful to the growth of CFU-S and viability of mice. At the same time, BMHSC exposed to normal oxygen level or inconstant and greatly changed oxygen concentrations could produce a high level of ROS, and the above-mentioned features and functional indicators are relatively low. It is concluded that ROS levels of HSC in BMHSCT are closely related with the oxygen concentration surrounding the cells and its stability. Low oxygen concentration and antioxidant intervention are helpful to transplantation of BMHSC.

Synthetic Secoisolariciresinol Diglucoside (LGM2605) Protects Human Lung in an Ex Vivo Model of Proton Radiation Damage.

PubMed

Velalopoulou, Anastasia; Chatterjee, Shampa; Pietrofesa, Ralph A; Koziol-White, Cynthia; Panettieri, Reynold A; Lin, Liyong; Tuttle, Stephen; Berman, Abigail; Koumenis, Constantinos; Christofidou-Solomidou, Melpo

2017-11-25

Radiation therapy for the treatment of thoracic malignancies has improved significantly by directing of the proton beam in higher doses on the targeted tumor while normal tissues around the tumor receive much lower doses. Nevertheless, exposure of normal tissues to protons is known to pose a substantial risk in long-term survivors, as confirmed by our work in space-relevant exposures of murine lungs to proton radiation. Thus, radioprotective strategies are being sought. We established that LGM2605 is a potent protector from radiation-induced lung toxicity and aimed in the current study to extend the initial findings of space-relevant, proton radiation-associated late lung damage in mice by looking at acute changes in human lung. We used an ex vivo model of organ culture where tissue slices of donor living human lung were kept in culture and exposed to proton radiation. We exposed donor human lung precision-cut lung sections (huPCLS), pretreated with LGM2605, to 4 Gy proton radiation and evaluated them 30 min and 24 h later for gene expression changes relevant to inflammation, oxidative stress, and cell cycle arrest, and determined radiation-induced senescence, inflammation, and oxidative tissue damage. We identified an LGM2605-mediated reduction of proton radiation-induced cellular senescence and associated cell cycle changes, an associated proinflammatory phenotype, and associated oxidative tissue damage. This is a first report on the effects of proton radiation and of the radioprotective properties of LGM2605 on human lung.

Synthetic Secoisolariciresinol Diglucoside (LGM2605) Protects Human Lung in an Ex Vivo Model of Proton Radiation Damage

PubMed Central

Velalopoulou, Anastasia; Chatterjee, Shampa; Pietrofesa, Ralph A.; Koziol-White, Cynthia; Panettieri, Reynold A.; Lin, Liyong; Tuttle, Stephen; Berman, Abigail; Koumenis, Constantinos; Christofidou-Solomidou, Melpo

2017-01-01

Radiation therapy for the treatment of thoracic malignancies has improved significantly by directing of the proton beam in higher doses on the targeted tumor while normal tissues around the tumor receive much lower doses. Nevertheless, exposure of normal tissues to protons is known to pose a substantial risk in long-term survivors, as confirmed by our work in space-relevant exposures of murine lungs to proton radiation. Thus, radioprotective strategies are being sought. We established that LGM2605 is a potent protector from radiation-induced lung toxicity and aimed in the current study to extend the initial findings of space-relevant, proton radiation-associated late lung damage in mice by looking at acute changes in human lung. We used an ex vivo model of organ culture where tissue slices of donor living human lung were kept in culture and exposed to proton radiation. We exposed donor human lung precision-cut lung sections (huPCLS), pretreated with LGM2605, to 4 Gy proton radiation and evaluated them 30 min and 24 h later for gene expression changes relevant to inflammation, oxidative stress, and cell cycle arrest, and determined radiation-induced senescence, inflammation, and oxidative tissue damage. We identified an LGM2605-mediated reduction of proton radiation-induced cellular senescence and associated cell cycle changes, an associated proinflammatory phenotype, and associated oxidative tissue damage. This is a first report on the effects of proton radiation and of the radioprotective properties of LGM2605 on human lung. PMID:29186841

Time-dependent effects of intermittent hydrostatic pressure on articular chondrocyte type II collagen and aggrecan mRNA expression.

PubMed

Smith, R L; Lin, J; Trindade, M C; Shida, J; Kajiyama, G; Vu, T; Hoffman, A R; van der Meulen, M C; Goodman, S B; Schurman, D J; Carter, D R

2000-01-01

The normal loading of joints during daily activities causes the articular cartilage to be exposed to high levels of intermittent hydrostatic pressure. This study quantified effects of intermittent hydrostatic pressure on expression of mRNA for important extracellular matrix constituents. Normal adult bovine articular chondrocytes were isolated and tested in primary culture, either as high-density monolayers or formed aggregates. Loaded cells were exposed to 10 MPa of intermittent hydrostatic pressure at a frequency of 1 Hz for periods of 2, 4, 8, 12, and 24 hrs. Other cells were intermittently loaded for a period of 4 hrs per day for 4 days. Semiquantitative reverse transcription polymerase chain reaction assays were used to assess mRNA signal levels for collagen types II and I and aggrecan. The results showed that type II collagen mRNA signal levels exhibited a biphasic pattern, with an initial increase of approximately five-fold at 4 and 8 hrs that subsequently decreased by 24 hrs. In contrast, aggrecan mRNA signal increased progressively up to three-fold throughout the loading period. Changing the loading profile to 4 hrs per day for 4 days increased the mRNA signal levels for type II collagen nine-fold and for aggrecan twenty-fold when compared to unloaded cultures. These data suggest that specific mechanical loading protocols may be required to optimally promote repair and regeneration of diseased joints.

Phosphatidylserine-targeted liposome for enhanced glioma-selective imaging.

PubMed

Zhang, Liang; Habib, Amyn A; Zhao, Dawen

2016-06-21

Phosphatidylserine (PS), which is normally intracellular, becomes exposed on the outer surface of viable endothelial cells (ECs) of tumor vasculature. Utilizing a PS-targeting antibody, we have recently established a PS-targeted liposomal (PS-L) nanoplatform that has demonstrated to be highly tumor-selective. Because of the vascular lumen-exposed PS that is immediately accessible without a need to penetrate the intact blood brain barrier (BBB), we hypothesize that the systemically administered PS-L binds specifically to tumor vascular ECs, becomes subsequently internalized into the cells and then enables its cargos to be efficiently delivered to glioma parenchyma. To test this, we exploited the dual MRI/optical imaging contrast agents-loaded PS-L and injected it intravenously into mice bearing intracranial U87 glioma. At 24 h, both in vivo optical imaging and MRI depicted enhanced tumor contrast, distinct from the surrounding normal brain. Intriguingly, longitudinal MRI revealed temporal and spatial intratumoral distribution of the PS-L by following MRI contrast changes, which appeared punctate in tumor periphery at an earlier time point (4 h), but became clustering and disseminated throughout the tumor at 24 h post injection. Importantly, glioma-targeting specificity of the PS-L was antigen specific, since a control probe of irrelevant specificity showed minimal accumulation in the glioma. Together, these results indicate that the PS-L nanoplatform enables the enhanced, glioma-targeted delivery of imaging contrast agents by crossing the tumor BBB efficiently, which may also serve as a useful nanoplatform for anti-glioma drugs.

[Changes in expression of Slingshot protein in hypoxic human intestinal epithelial cell and its relation with barrier function of the cells].

PubMed

Zhang, Jian; Wang, Pei; He, Wen; Wang, Fengjun

2016-04-01

To study the effect of hypoxia on Slingshot protein expression in human intestinal epithelial cell and its relation with changes in barrier function of the cells. The human intestinal epithelial cell line Caco-2 was used to reproduce monolayer-cells. One portion of the monolayer-cell specimens were divided into six parts according to the random number table, and they were respectively exposed to hypoxia for 0 (without hypoxia), 1, 2, 6, 12, and 24 h. Transepithelial electrical resistance (TER) was determined with an ohmmeter. Another portion of the monolayer-cell specimens were exposed to hypoxia as above. Western blotting was used to detect the protein expressions of zonula occludens 1 (ZO-1), occludin, claudin-1, Slingshot-1, Slingshot-2, and Slingshot-3. The remaining portion of the monolayer-cell specimens were also exposed to hypoxia as above. The content of fibrous actin (F-actin) and globular actin (G-actin) was determined by fluorescence method. The sample number of above-mentioned 3 experiments was respectively 10, 10, and 18 at each time point. Data were processed with one-way analysis of variance and Dunnett test. (1) Compared with that of cells exposed to hypoxia for 0 h, TER of cells exposed to hypoxia for 1 to 24 h was significantly reduced (P values below 0.01). (2) Compared with those of cells exposed to hypoxia for 0 h (all were 1.00), the protein expressions of ZO-1, occludin, and claudin-1 of cells exposed to hypoxia for 1 to 24 h were generally lower, especially those of cells exposed to hypoxia for 12 h or 24 h (respectively 0.69 ± 0.20, 0.47 ± 0.15, and 0.47 ± 0.22, P<0.05 or P<0.01). Compared with those of cells exposed to hypoxia for 0 h, the protein expressions of Slingshot-1 and Slingshot-3 of cells exposed to hypoxia for 1 to 24 h were not obviously changed (P values above 0.05). The protein expression of Slingshot-2 of cells was decreased at first and then gradually increased from hypoxia hour 1 to 24. The protein expression of Slingshot-2 of cells exposed to hypoxia for 24 h (1.54 ± 0.57) was significantly higher than that of cells exposed to hypoxia for 0 h (1.00, P<0.05). (3) Compared with those of cells exposed to hypoxia for 0 h, the content of F-actin of cells exposed to hypoxia for 1, 6, 12, and 24 h was significantly decreased, whereas the content of G-actin of cells exposed to hypoxia for 6-24 h was significantly increased, P<0.05 or P<0.01; the content of F-actin and G-actin of cells exposed to hypoxia for the other time points was not obviously changed (P values above 0.05). Hypoxia may cause cofilin activation after dephosphorylation and the depolymerization of F-actin by inducing Slingshot-2 protein expression, which in turn affects the tight junction of human intestinal epithelial cells, thus leading to deterioration of barrier function of these cells.

Pipette-based Method to Study Embryoid Body Formation Derived from Mouse and Human Pluripotent Stem Cells Partially Recapitulating Early Embryonic Development Under Simulated Microgravity Conditions

NASA Astrophysics Data System (ADS)

Shinde, Vaibhav; Brungs, Sonja; Hescheler, Jürgen; Hemmersbach, Ruth; Sachinidis, Agapios

2016-06-01

The in vitro differentiation of pluripotent stem cells partially recapitulates early in vivo embryonic development. More recently, embryonic development under the influence of microgravity has become a primary focus of space life sciences. In order to integrate the technique of pluripotent stem cell differentiation with simulated microgravity approaches, the 2-D clinostat compatible pipette-based method was experimentally investigated and adapted for investigating stem cell differentiation processes under simulated microgravity conditions. In order to keep residual accelerations as low as possible during clinorotation, while also guaranteeing enough material for further analysis, stem cells were exposed in 1-mL pipettes with a diameter of 3.5 mm. The differentiation of mouse and human pluripotent stem cells inside the pipettes resulted in the formation of embryoid bodies at normal gravity (1 g) after 24 h and 3 days. Differentiation of the mouse pluripotent stem cells on a 2-D pipette-clinostat for 3 days also resulted in the formation of embryoid bodies. Interestingly, the expression of myosin heavy chain was downregulated when cultivation was continued for an additional 7 days at normal gravity. This paper describes the techniques for culturing and differentiation of pluripotent stem cells and exposure to simulated microgravity during culturing or differentiation on a 2-D pipette clinostat. The implementation of these methodologies along with -omics technologies will contribute to understand the mechanisms regulating how microgravity influences early embryonic development.

Exposure to febrile-range hyperthermia potentiates Wnt signalling and epithelial-mesenchymal transition gene expression in lung epithelium.

PubMed

Potla, Ratnakar; Tulapurkar, Mohan E; Luzina, Irina G; Atamas, Sergei P; Singh, Ishwar S; Hasday, Jeffrey D

2018-02-01

As environmental and body temperatures vary, lung epithelial cells experience temperatures significantly different from normal core temperature. Our previous studies in human lung epithelium showed that: (i) heat shock accelerates wound healing and activates profibrotic gene expression through heat shock factor-1 (HSF1); (ii) HSF1 is activated at febrile temperatures (38-41 °C) and (iii) hypothermia (32 °C) activates and hyperthermia (39.5 °C) reduces expression of a subset of miRNAs that target protein kinase-Cα (PKCα) and enhance proliferation. We analysed the effect of hypo- and hyperthermia exposure on Wnt signalling by exposing human small airway epithelial cells (SAECs) and HEK293T cells to 32, 37 or 39.5 °C for 24 h, then analysing Wnt-3a-induced epithelial-mesenchymal transition (EMT) gene expression by qRT-PCR and TOPFlash reporter plasmid activity. Effects of miRNA mimics and inhibitors and the HSF1 inhibitor, KNK437, were evaluated. Exposure to 39.5 °C for 24 h increased subsequent Wnt-3a-induced EMT gene expression in SAECs and Wnt-3a-induced TOPFlash activity in HEK293T cells. Increased Wnt responsiveness was associated with HSF1 activation and blocked by KNK437. Overexpressing temperature-responsive miRNA mimics reduced Wnt responsiveness in 39.5 °C-exposed HEK293T cells, but inhibitors of the same miRNAs failed to restore Wnt responsiveness in 32 °C-exposed HEK293T cells. Wnt responsiveness, including expression of genes associated with EMT, increases after exposure to febrile-range temperature through an HSF1-dependent mechanism that is independent of previously identified temperature-dependent miRNAs. This process may be relevant to febrile fibrosing lung diseases, including the fibroproliferative phase of acute respiratory distress syndrome (ARDS) and exacerbations of idiopathic pulmonary fibrosis (IPF).

Evaluation of genetic damage in tobacco and arsenic exposed population of Southern Assam, India using buccal cytome assay and comet assay.

PubMed

Roy, Prasenjit; Mukherjee, Anita; Giri, Sarbani

2016-02-01

Ground water is the principal source of drinking water in Assam. Ground water contamination of arsenic in drinking water is a great concern for human health and considered as a human carcinogen. The present cytogenetic biomonitoring study was undertaken to investigate the genotoxic effects associated with people of southern Assam consuming arsenic contaminated water and chewing tobacco. Employing the buccal cytome assay, exfoliated cells were analyzed in 138 individuals of age range 22-42 years and divided into four groups. Group I (n=54) are participants residing in localities where ground water contains arsenic concentration below the permissible limit (<10μg/l) and without any tobacco chewing history. Group II (n=32) participants from the same area but they are tobacco chewers. Group III (n=24) participants from localities where significantly high arsenic contamination in ground water were observed. Whereas the Group IV (n=28) consists of participants from the arsenic contaminated area and also tobacco chewers. Body mass index (BMI) in all the groups are found to be nearly same and in normal range. Statistically significant (P<0.001) increase in genotoxic, cell death parameters and cell proliferation biomarkers were observed in the Group IV compared to other groups. In the comet assay, percent of tail DNA gradually increases among the groups and has statistical significance. Spearman correlation revealed strong positive correlation between the arsenic exposed peoples and the binucleated cells (r=0.4763; P<0.001). Amount of chewing tobacco had significant positive correlation with micronucleus frequency (r=0.268; P<0.05) and karyolitic cells (r=0.217; P<0.05) and also in the percentage of tail DNA (r=0.5532, P<0.001). A statistically significant increase in glucose content and decrease in hemoglobin content as well as acetylcholine esterase in the blood of exposed individuals was observed. Our preliminary study indicate that population exposed to arsenic through drinking water may become more susceptible towards chewing tobacco induced nuclear damage as evaluated by buccal cytome assay and comet assay. Copyright © 2015 Elsevier Inc. All rights reserved.

In-depth characterization of the fluorescent signal of HyPer, a probe for hydrogen peroxide, in bacteria exposed to external oxidative stress.

PubMed

Lim, Joseph B; Barker, Kimberly A; Huang, Beijing K; Sikes, Hadley D

2014-11-01

Genetically encoded, fluorescent biosensors have been developed to probe the activities of various signaling molecules inside cells ranging from changes in intracellular ion concentrations to dynamics of lipid second messengers. HyPer is a member of this class of biosensors and is the first to dynamically respond to hydrogen peroxide (H2O2), a reactive oxygen species that functions as a signaling molecule. However, detailed characterization of HyPer's signal is not currently available within the context of bacteria exposed to external oxidative stress, which occurs in the immunological response of higher organisms against invasive pathogenic bacteria. Here, we performed this characterization, specifically in Escherichia coli exposed to external H2O2. We found that the temporal behavior of the signal does not correspond exactly to peroxide concentration in the system as a function of time and expression of the sensor decreases the peroxide scavenging activity of the cell. We also determined the effects of cell number, both before and after normalization of externally added H2O2 to the number of cells. Finally, we report quantitative characteristics of HyPer's signal in this context, including the dynamic range of the signal, the signal-to-noise ratio, and the half saturation constant. These parameters show statistically meaningful differences in signal between two commonly used strains of E. coli, demonstrating how signal can vary with strain. Taken together, our results establish a systematic, quantitative framework for researchers seeking to better understand the role of H2O2 in the immunological response against bacteria, and for understanding potential differences in the details of HyPer's quantitative performance across studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Light at night activates IGF-1R/PDK1 signaling and accelerates tumor growth in human breast cancer xenografts.

PubMed

Wu, Jinghai; Dauchy, Robert T; Tirrell, Paul C; Wu, Steven S; Lynch, Darin T; Jitawatanarat, Potjana; Burrington, Christine M; Dauchy, Erin M; Blask, David E; Greene, Michael W

2011-04-01

Regulation of diurnal and circadian rhythms and cell proliferation are coupled in all mammals, including humans. However, the molecular mechanisms by which diurnal and circadian rhythms regulate cell proliferation are relatively poorly understood. In this study, we report that tumor growth in nude rats bearing human steroid receptor-negative MCF-7 breast tumors can be significantly accelerated by exposing the rats to light at night (LAN). Under normal conditions of an alternating light/dark cycle, proliferating cell nuclear antigen (PCNA) levels in tumors were maximal in the early light phase but remained at very low levels throughout the daily 24-hour cycle period monitored. Surprisingly, PCNA was expressed in tumors continually at a high level throughout the entire 24-hour period in LAN-exposed nude rats. Daily fluctuations of Akt and mitogen activated protein kinase activation in tumors were also disrupted by LAN. These fluctuations did not track with PCNA changes, but we found that activation of the Akt stimulatory kinase phosphoinositide-dependent protein kinase 1 (PDK1) directly correlated with PCNA levels. Expression of insulin-like growth factor 1 receptor (IGF-1R), an upstream signaling molecule for PDK1, also correlated with fluctuations of PDK1/PCNA in the LAN group. In addition, circulating IGF-1 concentrations were elevated in LAN-exposed tumor-bearing nude rats. Finally, RNAi-mediated knockdown of PDK1 led to a reduction in PCNA expression and cell proliferation in vitro and tumor growth in vivo, indicating that PDK1 regulates breast cancer growth in a manner correlated with PCNA expression. Taken together, our findings demonstrate that LAN exposure can accelerate tumor growth in vivo, in part through continuous activation of IGF-1R/PDK1 signaling.

Low-level infrared laser modulates muscle repair and chromosome stabilization genes in myoblasts.

PubMed

da Silva Neto Trajano, Larissa Alexsandra; Stumbo, Ana Carolina; da Silva, Camila Luna; Mencalha, Andre Luiz; Fonseca, Adenilson S

2016-08-01

Infrared laser therapy is used for skeletal muscle repair based on its biostimulative effect on satellite cells. However, shortening of telomere length limits regenerative potential in satellite cells, which occurs after each cell division cycle. Also, laser therapy could be more effective on non-physiologic tissues. This study evaluated low-level infrared laser exposure effects on mRNA expression from muscle injury repair and telomere stabilization genes in myoblasts in normal and stressful conditions. Laser fluences were those used in clinical protocols. C2C12 myoblast cultures were exposed to low-level infrared laser (10, 35, and 70 J/cm(2)) in standard or normal (10 %) and reduced (2 %) fetal bovine serum concentrations; total RNA was extracted for mRNA expression evaluation from muscle injury repair (MyoD and Pax7) and chromosome stabilization (TRF1 and TRF2) genes by real time quantitative polymerization chain reaction. Data show that low-level infrared laser increases the expression of MyoD and Pax7 in 10 J/cm(2) fluence, TRF1 expression in all fluences, and TRF2 expression in 70 J/cm(2) fluence in both 10 and 2 % fetal bovine serum. Low-level infrared laser increases mRNA expression from genes related to muscle repair and telomere stabilization in myoblasts in standard or normal and stressful conditions.

Mobile phone mast effects on common frog (Rana temporaria) tadpoles: the city turned into a laboratory.

PubMed

Balmori, Alfonso

2010-06-01

An experiment has been made exposing eggs and tadpoles of the common frog (Rana temporaria) to electromagnetic radiation from several mobile (cell) phone antennae located at a distance of 140 meters. The experiment lasted two months, from the egg phase until an advanced phase of tadpole prior to metamorphosis. Measurements of electric field intensity (radiofrequencies and microwaves) in V/m obtained with three different devices were 1.8 to 3.5 V/m. In the exposed group (n = 70), low coordination of movements, an asynchronous growth, resulting in both big and small tadpoles, and a high mortality (90%) was observed. Regarding the control group (n = 70) under the same conditions but inside a Faraday cage, the coordination of movements was normal, the development was synchronous, and a mortality of 4.2% was obtained. These results indicate that radiation emitted by phone masts in a real situation may affect the development and may cause an increase in mortality of exposed tadpoles. This research may have huge implications for the natural world, which is now exposed to high microwave radiation levels from a multitude of phone masts.

Hydrocortisone in culture protects the blast cells in acute myeloblastic leukemia from the lethal effects of cytosine arabinoside

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

Yang, G.S.; Wang, C.; Minkin, S.

The blast cells in acute myeloblastic leukemia (AML) respond to many of the same regulatory mechanisms that control normal hemopoiesis. These include the growth factors that bind to membrane receptors and steroid hormones or vitamins that have intracellular receptors. The authors report the effects in culture of the steroid glucocorticoid hydrocortisone on freshly explanted AML blasts from patients and on two continuous AML cell lines. Only small changes in clonogenic cell numbers in suspension cultures were seen in the presence of hydrocortisone. The most striking effect of the hormone was on the sensitivity of blasts cells to cytosine arabinoside (ara-C).more » In contrast to the response of AML blast cells to retinoic acid, a ligand for intracellular steroid receptors that sensitizes some blast populations to ara-C, hydrocortisone reduced the toxic effects of the drug. The protective action of hydrocortisone was not mediated through the cell cycle since exposure of blasts to hydrocortisone did not affect the percentage of cells in DNA synthesis as measured with the tritiated thymidine (3HTdR) suicide technique. The hydrocortisone effect could be demonstrated using a pulse (20 min) exposure protocol. Blasts pulsed with increasing specific activities of 3HTdR showed the usual response pattern with an initial loss in plating efficiency to about 50% of control, followed by a plateau, regardless of whether the cells had been exposed to hydrocortisone. Control blasts exposed to increasing ara-C concentrations gave very similar dose-response curves; in striking contrast, blast cells cultured in hydrocortisone, then pulsed with ara-C did not lose colony-forming ability even though the same population was sensitive to 3HTdR.« less

Survival, recovery and microcystin release of Microcystis aeruginosa in cold or dark condition

NASA Astrophysics Data System (ADS)

Ding, Yi; Gan, Nanqin; Liu, Jin; Zheng, Lingling; Li, Lin; Song, Lirong

2017-03-01

Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well known. In this study, we conducted experiments on the responses of two toxic Microcystis aeruginosa strains (FACHB-905 and FACHB-915) and their microcystin release in conditions of low temperature (15°C or 4°C, with illumination) or darkness, and subsequent recovery in standard conditions (25°C with illumination). On exposure to 15°C, a small decrease in cell viability was observed, but the cell number increased gradually, suggesting that M. aeruginosa FACHB-905 and FACHB-915 cells seem in general tolerant in 15°C. Interestingly, our results show that a higher carotenoid content and microcystin release potentially enhance the fitness of surviving cells at 15°C. M. aeruginosa cells exposed to lower temperature light stress (4°C) did not completely lose viability and retained the ability to reinitiate growth. In darkness, the maximum quantum yield ( F v/ F m) and the maximum electron transport rate (ETRmax) values and cell viability of M. aeruginosa cells gradually decreased with time. During the recovery period, the photosynthetic efficiency of M. aeruginosa reverted to the normal level. Additionally, M. aeruginosa FACHB-905 and FACHB-915 exposed to low temperature had increased caspase-3-like activity and DNA fragmentation, which suggests the occurrence of a type of cell death in M. aeruginosa cells under cold stress similar to programmed cell death. Overall, our findings could confer certain advantages on the Microcystis for surviving cold or dark conditions encountered in the annual cycle, and help explain its repeated occurrence in water blooms in large and shallow lakes.

Synergistic actions of pemphigus vulgaris IgG, Fas-ligand and tumor necrosis factor-alpha during induction of basal cell shrinkage and acantholysis.

PubMed

Orlov, Maxim D; Chernyavsky, Alex I; Arredondo, Juan; Grando, Sergei A

2006-11-01

This study tested a recently proposed "Basal Cell Shrinkage" hypothesis of pemphigus acantholysis through a quantitative analysis of individual and cooperative effects of pemphigus vulgaris (PV) IgG, Fas-ligand (Fas-L) and tumor necrosis factor-alpha (TNFalpha) on keratinocyte (KC) volume (i.e. cell size) and adhesive properties. Exposure of KC monolayers and MatTek EpiDermFT tissues cultures to the physiologic concentrations of Fas-L, TNFalpha or IgGs from two PV patients resulted in various degrees of reversible changes, which were not observed in control cultures either exposed to normal IgG or left intact. Within 12-24 h of exposure, basal cells in experimental cultures lost their ability to form stress fibers, retracted cytoplasmic aprons and formed keratin aggregates, indicating that their cytoskeleton collapsed. The cell volume decreased significantly (p < 0.05) as the polygonal cell shape changed to a round one. The shrunk cells detached from their neighbors and the substrate, resulting in a reciprocal increase of both the areas of acantholysis and the number of detached KCs, respectively. Since in the skin of PV patients, KCs are targeted by autoantibodies concomitantly with being exposed to autocrine and paracrine pro-apoptotic and pro-inflammatory cytokines, we combined PV IgG with Fas-L and/or TNFalpha in the cell culture experiments. This amplified several fold an ability of PV IgG to cause basal cell shrinkage and detachment. The obtained results demonstrated for the first time that PV IgG works together with Fas-L and TNFalpha to induce acantholysis via basal cell shrinkage, which provides a novel mechanism explaining successful treatment of PV patients with TNFalpha inhibitors.

Changes in antigen-presenting cell function in the spleen and lymph nodes of ultraviolet-irradiated mice

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

Gurish, M.F.; Lynch, D.H.; Daynes, R.A.

1982-03-01

It has been previously reported that mice exposed to ultraviolet (UV) radiation exhibit a decrease in splenic antigen-presenting cell (APC) function. The results presented here confirm this observation and further demonstrate that animals exposed daily to UV for extended periods of time (5 weeks instead of 6 days) no longer exhibit this depressed capability. In spite of the depression in splenic APC activity found in 6-day UV-irradiated mice, lymph node APC function from these same animals was elevated compared with that found in the lymph nodes from normal animals. Lymph node APC activity in animals that were splenectomized prior tomore » the UV irradiation, however, was not enhanced over controls. Treatment of animals with a chemical irritant (turpentine) also caused a depression in splenic APC function without modifying lymph node activity. Collectively, our findings suggest that the observed decrease in splenic APC activity, found after the first week of UV exposures, may be attributable to the migration of splenic APC to peripheral lymphoid tissue which drain the site of epidermal inflammation.« less

Biomonitoring of genotoxic risk in workers in a rubber factory: comparison of the Comet assay with cytogenetic methods and immunology.

PubMed

Somorovská, M; Szabová, E; Vodicka, P; Tulinská, J; Barancoková, M; Fábry, R; Lísková, A; Riegerová, Z; Petrovská, H; Kubová, J; Rausová, K; Dusinská, M; Collins, A

1999-09-30

Several substances used in rubber processing are known to be genotoxic. Workers in a rubber tyre factory, exposed to a broad spectrum of contaminants such as benzo[a]pyrene, benzo-fluoranthene, naphthalene, acetonaphthene, alkenes and 1,3-butadiene have been regularly examined for several years: chromosomal aberrations in lymphocytes, mutagenicity of urine (by use of the Ames test) and various parameters of blood and urine were assessed. An elevated level of mercapturic acid derivatives was found in the urine of employees, which is indicative of environmental exposure to toxicants with alkylating activity. We have now extended this study by examining genotoxicity with the modified Comet assay in parallel with chromosomal aberrations and micronucleus formation as well as immunological endpoints. Twenty-nine exposed workers from this factory were compared with 22 non-exposed administrative staff working in the same factory, as well as with 22 laboratory workers. The absolute numbers of peripheral leukocytes were significantly higher in the exposed group than in either of the control groups (p < 0.001). The erythrocyte mean cell volume was significantly higher in exposed workers in comparison with laboratory controls (p < 0.05). Percentages of lymphocytes, polymorphonuclear leukocytes, monocytes and eosinophils were not altered. The proliferative response of T- and B-cells to mitogen treatment when calculated per number of lymphocytes and adjusted for smoking, age and years of exposure did not differ between exposed and control groups. Endogenous strand breaks (including alkali-labile sites) and altered bases (formamidopyrimidine glycosylase- and endonuclease III-sensitive sites) were measured by the Comet assay in lymphocyte DNA. Exposed workers had significantly elevated levels of DNA breaks compared with office workers (p < 0.00001) or with laboratory controls (p < 0.00001). Micronuclei occurred at significantly higher frequencies in the exposed group than in controls (p < 0.00001), though the frequencies were all within the normal range. Significant correlations were seen between individual values of strand breaks, micronuclei and chromatid/chromosome breaks and certain immunological parameters.

Photovoltaic module and laminate

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

Bunea, Gabriela E.; Kim, Sung Dug; Kavulak, David F.J.

A photovoltaic module is disclosed. The photovoltaic module has a first side directed toward the sun during normal operation and a second, lower side. The photovoltaic module comprises a perimeter frame and a photovoltaic laminate at least partially enclosed by and supported by the perimeter frame. The photovoltaic laminate comprises a transparent cover layer positioned toward the first side of the photovoltaic module, an upper encapsulant layer beneath and adhering to the cover layer, a plurality of photovoltaic solar cells beneath the upper encapsulant layer, the photovoltaic solar cells electrically interconnected, a lower encapsulant layer beneath the plurality of photovoltaicmore » solar cells, the upper and lower encapsulant layers enclosing the plurality of photovoltaic solar cells, and a homogenous rear environmental protection layer, the rear environmental protection layer adhering to the lower encapsulant layer, the rear environmental protection layer exposed to the ambient environment on the second side of the photovoltaic module.« less

Induction of metallothionein synthesis in transplanted murine tumors by X irradiation

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

Kiyoshi, Shibuya; Masahiko Satoh; Yuzo, Watanabe

1995-07-01

Although recent studies have shown that radiation can induce metallothionein (MT) synthesis in normal tissues, the induction of tumor MT synthesis by irradiation has not been reported. We examined the accumulation of MT in the Meth-A tumor (mouse fibrosarcoma cells) transplanted into mice exposed to whole-body X irradiation. In the present study, the MT content in the tumor cells was increased by X irradiation in a dose-dependent manner. The MT level induced in the tumor cells by X irradiation was elevated not only after a single exposure but also after repeated exposures. Several studies have shown that MT is onemore » of the important cellular factors in resistance to various anti-cancer drugs and ionizing radiation. Thus our results suggest that the radiation-induced MT in the tumor cells may have to be taken into consideration when designing protocols for radio-and chemotherapy. 29 refs., 3 figs.« less

CaNa2EDTA chelation attenuates cell damage in workers exposed to lead--a pilot study.

PubMed

Čabarkapa, A; Borozan, S; Živković, L; Stojanović, S; Milanović-Čabarkapa, M; Bajić, V; Spremo-Potparević, B

2015-12-05

Lead induced oxidative cellular damage and long-term persistence of associated adverse effects increases risk of late-onset diseases. CaNa2EDTA chelation is known to remove contaminating metals and to reduce free radical production. The objective was to investigate the impact of chelation therapy on modulation of lead induced cellular damage, restoration of altered enzyme activities and lipid homeostasis in peripheral blood of workers exposed to lead, by comparing the selected biomarkers obtained prior and after five-day CaNa2EDTA chelation intervention. The group of smelting factory workers diagnosed with lead intoxication and current lead exposure 5.8 ± 1.2 years were administered five-day CaNa2EDTA chelation. Elevated baseline activity of antioxidant enzymes Cu, Zn-SOD and CAT as well as depleted thiols and increased protein degradation products-carbonyl groups and nitrites, pointing to Pb induced oxidative damage, were restored toward normal values following the treatment. Lead showed inhibitor potency on both RBC AChE and BChE in exposed workers, and chelation re-established the activity of BChE, while RBC AChE remained unaffected. Also, genotoxic effect of lead detected in peripheral blood lymphocytes was significantly decreased after therapy, exhibiting 18.9% DNA damage reduction. Administration of chelation reversed the depressed activity of serum PON 1 and significantly decreased lipid peroxidation detected by the post-chelation reduction of MDA levels. Lactate dehydrogenase LDH1-5 isoenzymes levels showed evident but no significant trend of restoring toward normal control values following chelation. CaNa2EDTA chelation ameliorates the alterations linked with Pb mediated oxidative stress, indicating possible benefits in reducing health risks associated with increased oxidative damage in lead exposed populations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Microarray data and gene expression statistics for Saccharomyces cerevisiae exposed to simulated asbestos mine drainage.

PubMed

Driscoll, Heather E; Murray, Janet M; English, Erika L; Hunter, Timothy C; Pivarski, Kara; Dolci, Elizabeth D

2017-08-01

Here we describe microarray expression data (raw and normalized), experimental metadata, and gene-level data with expression statistics from Saccharomyces cerevisiae exposed to simulated asbestos mine drainage from the Vermont Asbestos Group (VAG) Mine on Belvidere Mountain in northern Vermont, USA. For nearly 100 years (between the late 1890s and 1993), chrysotile asbestos fibers were extracted from serpentinized ultramafic rock at the VAG Mine for use in construction and manufacturing industries. Studies have shown that water courses and streambeds nearby have become contaminated with asbestos mine tailings runoff, including elevated levels of magnesium, nickel, chromium, and arsenic, elevated pH, and chrysotile asbestos-laden mine tailings, due to leaching and gradual erosion of massive piles of mine waste covering approximately 9 km 2 . We exposed yeast to simulated VAG Mine tailings leachate to help gain insight on how eukaryotic cells exposed to VAG Mine drainage may respond in the mine environment. Affymetrix GeneChip® Yeast Genome 2.0 Arrays were utilized to assess gene expression after 24-h exposure to simulated VAG Mine tailings runoff. The chemistry of mine-tailings leachate, mine-tailings leachate plus yeast extract peptone dextrose media, and control yeast extract peptone dextrose media is also reported. To our knowledge this is the first dataset to assess global gene expression patterns in a eukaryotic model system simulating asbestos mine tailings runoff exposure. Raw and normalized gene expression data are accessible through the National Center for Biotechnology Information Gene Expression Omnibus (NCBI GEO) Database Series GSE89875 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE89875).

Pro-inflammatory cytokines among individuals with skin findings long-term after sulfur mustard exposure: Sardasht-Iran Cohort Study.

PubMed

Moin, Athar; Khamesipour, Ali; Hassan, Zuhair Mohammad; Ebtekar, Massoumeh; Davoudi, Seyyed-Masoud; Vaez-Mahdavi, Mohammad-Reza; Soroush, Mohammad-Reza; Faghihzadeh, Soghrat; Naghizadeh, Mohammad-Mehdi; Ghazanfari, Tooba

2013-11-01

Sulfur mustard (SM) is a potent alkylating vesicant warfare chemical agent which causes severe damages to the interface organs, skin, lungs and eyes. The most common chronic skin lesions are mustard scars, xerosis, eczema, seborrheic dermatitis, cherry angioma and hyperpigmentation. This study is part of Sardasht-Iran Cohort Study (SICS) which was performed to compare the serum levels of inflammatory cytokines in SM-exposed individuals (n=372) with long-term relevant skin findings versus unexposed controls (n=128). Serum levels of pro-inflammatory cytokines including IL-1α, IL-1β, IL-1Ra, IL-6, and TNF (tumor necrosis factor) were titrated using ELISA method, 79.9% (n=290) of the exposed group and 60.5% (n=98) of the control group showed skin findings. In the exposed group, 52.1% (n=189) had only skin findings (OSFE) and in the control group, 32% (n=41) had no problem (NC, normal). Median serum levels of cytokines IL-1α, IL-1β, IL-1Ra, IL-6 and TNF-α in the OSFE group were: 1.077, 1.745, 25.640, 0.602 and 12.768 pg/ml, respectively. These values in normal controls were 1.889, 1.896, 32.190, 1.022 and 23.786 pg/ml, respectively which are higher than the corresponding values in the OSFE group, the differences were statistically significant only for IL-1α and TNF-α. This may be due to a damage incurred upon precursors of cytokine producing cells or failure of their functions, increase in suppressive mediators or other mechanisms which are not well known. More studies are needed in molecular dimensions of the immune and cytokine responses in the SM-exposed patients. Copyright © 2013 Elsevier B.V. All rights reserved.

Susceptibility of human liver cells to porcine endogenous retrovirus.

PubMed

Lin, Xinzi; Qi, Lin; Li, Zhiguo; Chi, Hao; Lin, Wanjun; Wang, Yan; Jiang, Zesheng; Pan, Mingxin; Gao, Yi

2013-12-01

The risk of porcine endogenous retrovirus infection is a major barrier for pig-to-human xenotransplant. Porcine endogenous retrovirus, present in porcine cells, can infect many human and nonhuman primate cells in vitro, but there is no evidence available about in vitro infection of human liver cells. We investigated the susceptibility of different human liver cells to porcine endogenous retrovirus. The supernatant from a porcine kidney cell line was added to human liver cells, including a normal hepatocyte cell line (HL-7702 cells), primary hepatocytes (Phh cells), and a liver stellate cell line (Lx-2 cells), and to human embryonic kidney cells as a reference control. Expression of the porcine endogenous retrovirus antigen p15E in the human cells was evaluated with polymerase chain reaction, reverse transcription-polymerase chain reaction, and Western blot. The porcine endogenous retrovirus antigen p15E was not expressed in any human liver cells (HL-7702, Phh, or Lx-2 cells) that had been exposed to supernatants from porcine kidney cell lines. Porcine endogenous retrovirus-specific fragments were amplified in human kidney cells. Human liver cells tested were not susceptible to infection by porcine endogenous retrovirus. Therefore, not all human cells are susceptible to porcine endogenous retrovirus.

Effect of nickel chloride on cell proliferation.

PubMed

D'Antò, Vincenzo; Valletta, Rosa; Amato, Massimo; Schweikl, Helmut; Simeone, Michele; Paduano, Sergio; Rengo, Sandro; Spagnuolo, Gianrico

2012-01-01

Metal alloys used in dentistry and in other biomedical fields may release nickel ions in the oral environment. The release of nickel might influence the normal biological and physiological processes, including tissue wound healing, cell growth and proliferation. The aim of this study was to evaluate in vitro the effects of nickel ions on cell cycle, viability and proliferation. Human osteosarcoma cells (U2OS) and human keratinocytes (HaCat) were exposed to different nickel chloride (NiCl(2)) concentrations (0 - 5mM) for various periods exposure. The viability of cultured cells was estimated by flow cytometry using Annexin V-FITC and Propidium Iodide (PI). Cell proliferation was evaluated by using carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and flow cytometry. Finally, the effects of NiCl(2) on cell cycle were assessed and quantified by flow cytometry. Statistical analysis was performed by means of ANOVA followed by Tukey's test. NiCl(2) induced a dose and time dependent decrease in cell viability. After 24h, 1mM NiCl(2) caused a similar and significant reduction of viability in U2OS and HaCat cells, while higher NiCl(2) concentrations and longer exposure times showed a reduced cytotoxic effect in HaCat as compared to U2OS cells. Exposure to NiCl(2) caused a dose- and time-dependent inhibition of cell proliferation in both cell lines tested, with a prominent effect on U2OS cells. Furthermore, both cell lines exposed to NiCl(2) exhibited significant changes in cell cycle distribution after 24h exposure 2mM NiCl2, as compared to untreated cells (p<0.05). Our results indicate that release of nickel ions may affect cell proliferation. The inhibition of cell growth by NiCl2 is mediated by both cell cycle arrest and by induction of cell death.

Effect of Nickel Chloride on Cell Proliferation

PubMed Central

D’Antò, Vincenzo; Valletta, Rosa; Amato, Massimo; Schweikl, Helmut; Simeone, Michele; Paduano, Sergio; Rengo, Sandro; Spagnuolo, Gianrico

2012-01-01

Objective: Metal alloys used in dentistry and in other biomedical fields may release nickel ions in the oral environment. The release of nickel might influence the normal biological and physiological processes, including tissue wound healing, cell growth and proliferation. The aim of this study was to evaluate in vitro the effects of nickel ions on cell cycle, viability and proliferation. Materials and Methods: Human osteosarcoma cells (U2OS) and human keratinocytes (HaCat) were exposed to different nickel chloride (NiCl2) concentrations (0 - 5mM) for various periods exposure. The viability of cultured cells was estimated by flow cytometry using Annexin V-FITC and Propidium Iodide (PI). Cell proliferation was evaluated by using carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and flow cytometry. Finally, the effects of NiCl2 on cell cycle were assessed and quantified by flow cytometry. Statistical analysis was performed by means of ANOVA followed by Tukey’s test. Results: NiCl2 induced a dose and time dependent decrease in cell viability. After 24h, 1mM NiCl2 caused a similar and significant reduction of viability in U2OS and HaCat cells, while higher NiCl2 concentrations and longer exposure times showed a reduced cytotoxic effect in HaCat as compared to U2OS cells. Exposure to NiCl2 caused a dose- and time-dependent inhibition of cell proliferation in both cell lines tested, with a prominent effect on U2OS cells. Furthermore, both cell lines exposed to NiCl2 exhibited significant changes in cell cycle distribution after 24h exposure 2mM NiCl2, as compared to untreated cells (p<0.05). Conclusion: Our results indicate that release of nickel ions may affect cell proliferation. The inhibition of cell growth by NiCl2 is mediated by both cell cycle arrest and by induction of cell death. PMID:23198004

Human adipose tissue from normal and tumoral breast regulates the behavior of mammary epithelial cells.

PubMed

Pistone Creydt, Virginia; Fletcher, Sabrina Johanna; Giudice, Jimena; Bruzzone, Ariana; Chasseing, Norma Alejandra; Gonzalez, Eduardo Gustavo; Sacca, Paula Alejandra; Calvo, Juan Carlos

2013-02-01

Stromal-epithelial interactions mediate both breast development and breast cancer progression. In the present work, we evaluated the effects of conditioned media (CMs) of human adipose tissue explants from normal (hATN) and tumor (hATT) breast on proliferation, adhesion, migration and metalloproteases activity on tumor (MCF-7 and IBH-7) and non-tumor (MCF-10A) human breast epithelial cell lines. Human adipose tissues were obtained from patients and the conditioned medium from hATN and hATT collected after 24 h of incubation. MCF-10A, MCF-7 and IBH-7 cells were grown and incubated with CMs and proliferation and adhesion, as well as migration ability and metalloprotease activity, of epithelial cells after exposing cell cultures to hATN- or hATT-CMs were quantified. The statistical significance between different experimental conditions was evaluated by one-way ANOVA. Tukey's post hoc tests were performed. Tumor and non-tumor breast epithelial cells significantly increased their proliferation activity after 24 h of treatment with hATT-CMs compared to control-CMs. Furthermore, cellular adhesion of these two tumor cell lines was significantly lower with hATT-CMs than with hATN-CMs. Therefore, hATT-CMs seem to induce significantly lower expression or less activity of the components involved in cellular adhesion than hATN-CMs. In addition, hATT-CMs induced pro-MMP-9 and MMP-9 activity and increased the migration of MCF-7 and IBH-7 cells compared to hATN-CMs. We conclude that the microenvironment of the tumor interacts in a dynamic way with the mutated epithelium. This evidence leads to the possibility to modify the tumor behavior/phenotype through the regulation or modification of its microenvironment. We developed a model in which we obtained CMs from adipose tissue explants completely, either from normal or tumor breast. In this way, we studied the contribution of soluble factors independently of the possible effects of direct cell contact.

Immune defects in families and patients with xeroderma pigmentosum and trichothiodystrophy.

PubMed Central

Mariani, E; Facchini, A; Honorati, M C; Lalli, E; Berardesca, E; Ghetti, P; Marinoni, S; Nuzzo, F; Astaldi Ricotti, G C; Stefanini, M

1992-01-01

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease characterized by photosensitivity, a high incidence of cancer in sun-exposed portions of the skin and a reduced capacity to repair the u.v.-induced DNA damage. One of the XP mutations (XP-D) has also been identified in patients affected by trichothiodystrophy (TTD), a rare autosomal recessive disease characterized by brittle hair, mental and physical retardation, peculiar face and ichthyosis. However, in these patients there is no evidence of increased skin tumour incidence. Since an impairment of cell-mediated immunity has been proposed as a co-factor in the cancer proneness of XP patients, we investigated the involvement of immune defect(s) in five XP patients, five TTD patients, their parents, and 24 TTD relatives. We evaluated the phenotype of circulating lymphocytes, natural killer (NK) cell lytic activity, target cell binding of NK cells at single cell level and the effect of interferons (IFN) alpha and beta on NK cell activity. The relative proportion of CD3+ and CD4+ circulating lymphocytes was reduced in XP but not in TTD patients. NK cell lytic activity was decreased in XP patients and their mothers, but their fathers showed normal lytic activity. NK activity varied among TTD families: four out of five patients and their relatives presented low NK cell activity, and one family was normal. In TTD family members, NK activity increased after incubation with IFN-alpha or IFN-beta, but never reached normal values. In contrast, in XP patients and their mothers, the defect was almost completely corrected after in vitro incubation with IFN-alpha or IFN-beta. Our study indicates impaired NK lytic activity in the majority of TTD and XP patients and that this defect is present also in members of their families. In addition, XP patients present a low number of circulating T cells. These multiple abnormalities, together with DNA repair defects, could be related to the increased cancer risk in XP patients. PMID:1535035

Functional antigen binding by the defective B cells of CBA/N mice.

PubMed

Snippe, H; Merchant, B; Lizzio, E F; Inman, J K

1982-01-01

CBA/N mice have an X-linked B cell defect which prevents them from responding to nonmitogenic thymic independent (TI-2) antigens such as dinitrophenylated DNP-Ficoll (1,2). The F1 male progeny of CBA/N female mice express the same defect. Spleen cell suspensions from such defective mice (CBA/N X C3H/HeN F1 males) could not respond to DNP-Ficoll following in vitro immunization and subsequent transfer into irradiated, syngeneic, F1 male recipients as expected. In contrast, normal CBA/N X C3H/HeN F1 female spleen cells could respond and effect a "rescue"; they mounted strong plaque-forming cell responses 7 days after in vitro exposure to DNP-Ficoll and subsequent transfer into irradiated F1 male recipients. Defective F1 male spleen cells, however, could bind significant quantities of 125I-DNP-Ficoll after in vitro exposure. Extensive washing of these spleen cells could not reverse this binding. Such DNP-Ficoll-exposed and washed F1 male spleen cells could, after transfer, aid normal untreated F1 female cells in their rescue function. The defective F1 male spleen cells could convey immunogenic quantities of DNP-Ficoll to the "rescuing" F1 female cells. Mitomycin treatment of F1 male cells did not interfere with their conveyor function. Goat anti-mouse mu serum impeded the passive antigen conveyor function of defective F1 male cells as did prior exposure to high concentrations of free DNP hapten. Our data support the view that the B cell defect of CBA/N X C3H/HeN F1 male mice does not relate to antigen binding, but rather to an inability to be effectively triggered by certain cell-bound polymeric antigens.

Trivalent chromium: assessing the genotoxic risk of an essential trace element and widely used human and animal nutritional supplement.

PubMed

Eastmond, David A; Macgregor, James T; Slesinski, Ronald S

2008-01-01

Trivalent chromium [Cr(III)] is recognized as an essential nutrient, and is widely used as a nutritional supplement for humans and animals. Recent reports of the induction of genetic damage in cultured cells exposed to Cr(III) compounds in vitro have heightened the concern that Cr(III) compounds may exert genotoxic effects under certain conditions, raising the question of the relative benefit versus risk of dietary and feed supplementation practices. We have reviewed the literature since 1990 on genotoxic effects of Cr(III) compounds to determine whether recent findings provide a sufficient weight of evidence to modify the conclusions about the safety of this dietary supplement reached in the several comprehensive reviews conducted during the period 1990-2004. The extensive literature on genotoxic effects of Cr(III) compounds includes many instances of conflicting information, with both negative and positive findings often reported in similar test systems. Outcomes of in vitro tests conducted with Cr(III) in cultured cells are quite variable regardless of the chemical form of the chromium compound tested. The in vitro data show that Cr(III) has the potential to react with DNA and to cause DNA damage in cell culture systems, but under normal circumstances, restricted access of Cr(III) to cells in vivo limits or prevents genotoxicity in biological systems. The available in vivo evidence suggests that genotoxic effects are very unlikely to occur in humans or animals exposed to nutritional or to moderate recommended supplemental levels of Cr(III). However, excessive intake of Cr(III) supplements does not appear to be warranted at this time. Thus, like other nutrients that have exhibited genotoxic effects in vitro under high exposure conditions, nutritional benefits appear to outweigh the theoretical risk of genotoxic effects in vivo at normal or modestly elevated physiological intake levels.

Chicken embryo fibroblasts exposed to weak, time-varying magnetic fields share cell proliferation, adenosine deaminase activity, and membrane characteristics of transformed cells

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

Parola, A.H.; Porat, N.; Kiesow, L.A.

1993-01-01

Chicken embryo fibroblasts (CEF) exposed to a sinusoidally varying magnetic field (SVMF) (100 Hz, 700 microT, for 24 h) showed a remarkable rise of segmental rotational relaxation rate of adenosine deaminase (ADA, EC 3.5.4.4) as determined by multifrequency phase fluorometry. Pyrene-labeled, small subunit ADA was applied to cultured (normal) CEF, which have available and abundant ADA complexing protein (ADCP) on their plasma membranes. Sine-wave-modulated fluorometry of the pyrene yielded a profile of phase angle vs. modulation frequency. In SVMF-treated cells and in Rous-sarcoma-virus (RSV) transformed cells the differential phase values at low modulation frequencies of the excitation are remarkably reduced.more » This effect is magnetic rather than thermal, because the temperature was carefully controlled and monitored; nevertheless to further check this matter we studied CEF, infected by the RSV-Ts68 temperature-sensitive mutant (36 degrees C transformed, 41 degrees C revertant). When grown at 36 degrees C in the SVMF, cells did not show the slightest trend towards reversion, as would be expected had there been local heating. Concomitant with the increased segmental rotational relaxation rate of ADA, there was a decrease in fluorescence lifetime and a slight, yet significant, increase in membrane lipid microfluidity. These biophysical observations prompted us to examine the effect of SVMF on cell proliferation and ADA activity (a malignancy marker): higher rates of cell proliferation and reduced specific activity of ADA were observed.« less

Glioprotective effects of Ashwagandha leaf extract against lead induced toxicity.

PubMed

Kumar, Praveen; Singh, Raghavendra; Nazmi, Arshed; Lakhanpal, Dinesh; Kataria, Hardeep; Kaur, Gurcharan

2014-01-01

Withania somnifera (Ashwagandha), also known as Indian Ginseng, is a well-known Indian medicinal plant due to its antioxidative, antistress, antigenotoxic, and immunomodulatory properties. The present study was designed to assess and establish the cytoprotective potential of Ashwagandha leaf aqueous extract against lead induced toxicity. Pretreatment of C6 cells with 0.1% Ashwagandha extract showed cytoprotection against 25  μM to 400 μM concentration of lead nitrate. Further pretreatment with Ashwagandha extract to lead nitrate exposed cells (200  μM) resulted in normalization of glial fibrillary acidic protein (GFAP) expression as well as heat shock protein (HSP70), mortalin, and neural cell adhesion molecule (NCAM) expression. Further, the cytoprotective efficacy of Ashwagandha extract was studied in vivo. Administration of Ashwagandha extract provided significant protection to lead induced altered antioxidant defense that may significantly compromise normal cellular function. Ashwagandha also provided a significant protection to lipid peroxidation (LPx) levels, catalase, and superoxide dismutase (SOD) but not reduced glutathione (GSH) contents in brain tissue as well as peripheral organs, liver and kidney, suggesting its ability to act as a free radical scavenger protecting cells against toxic insult. These results, thus, suggest that Ashwagandha water extract may have the potential therapeutic implication against lead poisoning.

Efficient Active Oxygen Free Radical Generated in Tumor Cell by Loading-(HCONH2)·H2O2 Delivery Nanosystem with Soft-X-ray Radiotherapy

PubMed Central

Xu, Lei; Shao, Yiran; Chang, Chengkang; Zhu, Yingchun

2018-01-01

Tumor hypoxia is known to result in radiotherapy resistance and traditional radiotherapy using super-hard X-ray irradiation can cause considerable damage to normal tissue. Therefore, formamide peroxide (FPO) with high reactive oxygen content was employed to enhance the oxygen concentration in tumor cells and increase the radio-sensitivity of low-energy soft-X-ray. To improve stability of FPO, FPO is encapsulated into polyacrylic acid (PAA)-coated hollow mesoporous silica nanoparticles (FPO@HMSNs-PAA). On account of the pH-responsiveness of PAA, FPO@HMSNs-PAA will release more FPO in simulated acidic tumor microenvironment (pH 6.50) and subcellular endosomes (pH 5.0) than in simulated normal tissue media (pH 7.40). When exposed to soft-X-ray irradiation, the released FPO decomposes into oxygen and the generated oxygen further formed many reactive oxygen species (ROS), leading to significant tumor cell death. The ROS-mediated cytotoxicity of FPO@HMSNs-PAA was confirmed by ROS-induced green fluorescence in tumor cells. The presented FPO delivery system with soft-X-ray irradiation paves a way for developing the next opportunities of radiotherapy toward efficient tumor prognosis. PMID:29649155

Anti-tumor effects of osthole on ovarian cancer cells in vitro.

PubMed

Jiang, Guoqiang; Liu, Jia; Ren, Baoyin; Tang, Yawei; Owusu, Lawrence; Li, Man; Zhang, Jing; Liu, Likun; Li, Weiling

2016-12-04

Cnidium monnieri (L.) Cusson is a commonly used traditional Chinese medicine to treat gynecological disease in some countries. Osthole, an active O-methylated coumadin isolated from Cnidium monnieri (L.) Cusson, has been shown to induce various beneficial biochemical effects such as anti-seizure and anti-inflammatory effects. However, the anti-tumor mechanism of osthole is not well known. Here, we show that osthole inhibited the proliferation and migration of two widely used ovarian cancer cell lines, A2780 and OV2008 cells, in a dose-dependent manner. The study investigated the molecular mechanisms underlying ovarian cancer cells proliferation, apoptosis, cell cycle arrest and migration triggered by osthole. Ovarian cancer cell lines A2780, OV2008 and normal ovarian cell line IOSE80 were used as experimental model. MTT assay was employed to evaluate cell viability. Flow cytometry assays were performed to confirm apoptosis and cell cycle. We employed wound healing and transwell assays to delineate invasive and migratory potential triggered by osthole. MTT assays indicated that cell viability significantly decreased in ovarian cancer cells treated with osthole without effect on normal ovarian cells. Flow cytometric analysis revealed that osthole suppressed cells proliferation by promoting G2/M arrest and inducing apoptosis. The underlying mechanisms involved were regulation of the relative apoptotic protein Bcl-2, Bax and Caspase 3/9. In addition, wound healing and transwell assays revealed that the migratory potential and activity of matrix metalloproteinase MMP-2 and MMP-9 were markedly inhibited when cells were exposed to osthole. Our findings suggested that osthole has the potential to be used in novel anti-cancer therapeutic formulations for ovarian cancer treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of mitomycin-C on normal dermal fibroblasts.

PubMed

Chen, Theodore; Kunnavatana, Shaun S; Koch, R James

2006-04-01

To evaluate the effects of mitomycin-C on the growth and autocrine growth factor production of human dermal fibroblasts from the face. In vitro study using normal adult dermal fibroblast cell lines in a serum-free model. Cell cultures were exposed to 4 mg/mL, 0.4 mg/mL, 0.04 mg/mL, 0.004 mg/mL, and 0.0004 mg/mL concentrations of mitomycin-C solution. Cell counts were performed, and the cell-free supernatants were collected at 0, 1, 3, and 5 days after the initial exposure. Population doubling times were calculated and supernatants were quantitatively assayed for basic fibroblast growth factor (bFGF) and transforming growth factor (TGF)-beta1. Continuous exposure to mitomycin-C caused fibroblast cell death by day 7 at all tested concentrations. A 4 minute exposure to mitomycin-C at 4 mg/mL caused rapid fibroblast cell death. A 4-minute exposure to mitomycin-C at either 0.4 mg/mL or 0.04 mg/mL resulted in decreased fibroblast proliferation. A 4 minute exposure to mitomycin-C at 0.4 mg/mL resulted in a marked increase in the production of both bFGF and TGF-beta1. A clinically ideal concentration of mitomycin-C would slow fibroblast proliferation yet not cause cell death to allow for a wound healing response. Mitomycin-C 0.4 mg/mL for 4 minutes satisfies the above criteria in vitro.

Workers exposed to wood dust have an increased micronucleus frequency in nasal and buccal cells: results from a pilot study.

PubMed

Bruschweiler, Evin Danisman; Hopf, Nancy B; Wild, Pascal; Huynh, Cong Khanh; Fenech, Michael; Thomas, Philip; Hor, Maryam; Charriere, Nicole; Savova-Bianchi, Dessislava; Danuser, Brigitta

2014-05-01

Wood dust is recognised as a human carcinogen, based on the strong association of wood dust exposure and the elevated risk of malignant tumours of the nasal cavity and paranasal sinuses [sino-nasal cancer (SNC)]. The study aimed to assess genetic damage in workers exposed to wood dust using biomarkers in both buccal and nasal cells that reflect genome instability events, cellular proliferation and cell death frequencies. Nasal and buccal epithelial cells were collected from 31 parquet layers, installers, carpenters and furniture workers (exposed group) and 19 non-exposed workers located in Switzerland. Micronucleus (MN) frequencies were scored in nasal and buccal cells collected among woodworkers. Other nuclear anomalies in buccal cells were measured through the use of the buccal micronucleus cytome assay. MN frequencies in nasal and buccal cells were significantly higher in the exposed group compared to the non-exposed group; odds ratio for nasal cells 3.1 [95% confidence interval (CI) 1.8-5.1] and buccal cells 1.8 (95% CI 1.3-2.4). The exposed group had higher frequencies of cells with nuclear buds, karyorrhectic, pyknotic, karyolytic cells and a decrease in the frequency of basal, binucleated and condensed cells compared to the non-exposed group. Our study confirms that woodworkers have an elevated risk for chromosomal instability in cells of the aerodigestive tract. The MN assay in nasal cells may become a relevant biomonitoring tool in the future for early detection of SNC risk. Future studies should seek to standardise the protocol for MN frequency in nasal cells similar to that for MN in buccal cells.

TRX-ASK1-JNK signaling regulation of cell density-dependent cytotoxicity in cigarette smoke-exposed human bronchial epithelial cells.

PubMed

Lee, Yong Chan; Chuang, Chun-Yu; Lee, Pak-Kei; Lee, Jin-Soo; Harper, Richart W; Buckpitt, Alan B; Wu, Reen; Oslund, Karen

2008-05-01

Cigarette smoke is a major environmental air pollutant that injures airway epithelium and incites subsequent diseases including chronic obstructive pulmonary disease. The lesion that smoke induces in airway epithelium is still incompletely understood. Using a LIVE/DEAD cytotoxicity assay, we observed that subconfluent cultures of bronchial epithelial cells derived from both human and monkey airway tissues and an immortalized normal human bronchial epithelial cell line (HBE1) were more susceptible to injury by cigarette smoke extract (CSE) and by direct cigarette smoke exposure than cells in confluent cultures. Scraping confluent cultures also caused an enhanced cell injury predominately in the leading edge of the scraped confluent cultures by CSE. Cellular ATP levels in both subconfluent and confluent cultures were drastically reduced after CSE exposure. In contrast, GSH levels were significantly reduced only in subconfluent cultures exposed to smoke and not in confluent cultures. Western blot analysis demonstrated ERK activation in both confluent and subconfluent cultures after CSE. However, activation of apoptosis signal-regulating kinase 1 (ASK1), JNK, and p38 were demonstrated only in subconfluent cultures and not in confluent cultures after CSE. Using short interfering RNA (siRNA) to JNK1 and JNK2 and a JNK inhibitor, we attenuated CSE-mediated cell death in subconfluent cultures but not with an inhibitor of the p38 pathway. Using the tetracycline (Tet)-on inducible approach, overexpression of thioredoxin (TRX) attenuated CSE-mediated cell death and JNK activation in subconfluent cultures. These results suggest that the TRX-ASK1-JNK pathway may play a critical role in mediating cell density-dependent CSE cytotoxicity.

Long-term Fate Mapping to Assess the Impact of Postnatal Isoflurane Exposure on Hippocampal Progenitor Cell Productivity.

PubMed

Jiang, Yifei; Tong, Dongyi; Hofacer, Rylon D; Loepke, Andreas W; Lian, Qingquan; Danzer, Steve C

2016-12-01

Exposure to isoflurane increases apoptosis among postnatally generated hippocampal dentate granule cells. These neurons play important roles in cognition and behavior, so their permanent loss could explain deficits after surgical procedures. To determine whether developmental anesthesia exposure leads to persistent deficits in granule cell numbers, a genetic fate-mapping approach to label a cohort of postnatally generated granule cells in Gli1-CreER::GFP bitransgenic mice was utilized. Green fluorescent protein (GFP) expression was induced on postnatal day 7 (P7) to fate map progenitor cells, and mice were exposed to 6 h of 1.5% isoflurane or room air 2 weeks later (P21). Brain structure was assessed immediately after anesthesia exposure (n = 7 controls and 8 anesthesia-treated mice) or after a 60-day recovery (n = 8 controls and 8 anesthesia-treated mice). A final group of C57BL/6 mice was exposed to isoflurane at P21 and examined using neurogenesis and cell death markers after a 14-day recovery (n = 10 controls and 16 anesthesia-treated mice). Isoflurane significantly increased apoptosis immediately after exposure, leading to cell death among 11% of GFP-labeled cells. Sixty days after isoflurane exposure, the number of GFP-expressing granule cells in treated animals was indistinguishable from control animals. Rates of neurogenesis were equivalent among groups at both 2 weeks and 2 months after treatment. These findings suggest that the dentate gyrus can restore normal neuron numbers after a single, developmental exposure to isoflurane. The authors' results do not preclude the possibility that the affected population may exhibit more subtle structural or functional deficits. Nonetheless, the dentate appears to exhibit greater resiliency relative to nonneurogenic brain regions, which exhibit permanent neuron loss after isoflurane exposure.

Irradiation with heavy-ion particles changes the cellular distribution of human histone acetyltransferase HAT1.

PubMed

Lebel, Emily A; Boukamp, Petra; Tafrov, Stefan T

2010-06-01

Hat1 was the first histone acetyltransferase identified; however, its biological function is still unclear. In this report, it is shown for the first time that human Hat1 has two isoforms. Isoform a has 418 amino acids (aa) and is localized exclusively in the nuclear matrix of normal human keratinocytes (NHKs). Isoform b has 334 aa and is located in the cytoplasm, the nucleoplasm, attached to the chromatin and to the nuclear matrix. Immunohistochemical analyses revealed that the bulk of Hat1 is confined to the nucleus, with much lesser amounts in the cytoplasm. Cells undergoing mitotic division have an elevated amount of Hat1 compared to those that are non-mitotic. Senescent cells, however, exhibit a higher concentration of Hat1 in the cytoplasm compare to proliferating cells and the amount of Hat1 in the nucleus decreases with the progression of senescence. NHKs exposed to hydrogen peroxide (H(2)O(2)) or to a beam of high mass and energy ion particles displayed bright nuclear staining for Hat1, a phenotype that was not observed in NHKs exposed to gamma-rays. We established that the enhanced nuclear staining for Hat1 in response to these treatments is regulated by the PI3K and the mitogen-activated protein kinase signaling pathways. Our observations clearly implicate Hat1 in the cellular response assuring the survival of the treated cells.

Effect of 900 MHz electromagnetic fields on nonthermal induction of heat-shock proteins in human leukocytes.

PubMed

Lim, Hooi B; Cook, Greg G; Barker, Anthony T; Coulton, Les A

2005-01-01

Despite many studies, the evidence as to whether radiofrequency fields are detrimental to health remains controversial, and the debate continues. Cells respond to some abnormal physiological conditions by producing cytoprotective heat-shock (or stress) proteins. The aim of this study was to determine whether exposure to mobile phone-type radiation causes a nonthermal stress response in human leukocytes. Human peripheral blood was sham-exposed or exposed to 900 MHz fields (continuous-wave or GSM-modulated signal) at three average specific absorption rates (0.4, 2.0 and 3.6 W/kg) for different durations (20 min, 1 h and 4 h) in a calibrated TEM cell placed in an incubator to give well-controlled atmospheric conditions at 37 degrees C and 95% air/5% CO(2). Positive (heat-stressed at 42 degrees C) and negative (kept at 37 degrees C) control groups were incubated simultaneously in the same incubator. Heat caused an increase in the number of cells expressing stress proteins (HSP70, HSP27), measured using flow cytometry, and this increase was dependent on time. However, no statistically significant difference was detected in the number of cells expressing stress proteins after RF-field exposure. These results suggest that mobile phone-type radiation is not a stressor of normal human lymphocytes and monocytes, in contrast to mild heating.

Matrix remodeling maintains ESC self-renewal by activating Stat3

PubMed Central

Przybyla, Laralynne M.; Theunissen, Thorold W.; Jaenisch, Rudolf; Voldman, Joel

2013-01-01

While a variety of natural and synthetic matrices have been used to influence embryonic stem cell (ESC) self-renewal or differentiation, and ESCs also deposit a rich matrix of their own, the mechanisms behind how extracellular matrix affects cell fate are largely unexplored. The ESC matrix is continuously remodeled by matrix metalloproteinases (MMPs), a process that we find is enhanced by the presence of mouse embryonic fibroblast feeders in a paracrine manner. Matrix remodeling by MMPs aids in the self-renewal of ESCs, as inhibition of MMPs inhibits the ability of ESCs to self-renew. We also find that addition of the interstitial collagenase MMP1 is sufficient to maintain long-term LIF-independent mESC self-renewal in a dose-dependent manner. This remarkable ability is due to the presence of endogenously produced self-renewal-inducing signals, including the LIF-family ligand CNTF, that are normally trapped within the ECM and become exposed upon MMP-induced matrix remodeling to signal through JAK and Stat3. These results uncover a new role for feeder cells in maintaining self-renewal and show that mESCs normally produce sufficient levels of autocrine-acting pro-self-renewal ligands. PMID:23404867

Attenuating a sickle cell crisis with annexin V.

PubMed

Kennedy, James Randall

2015-05-01

A sickle cell crisis is a painful and dangerous condition that defies effective treatment but fortunately it usually terminates spontaneously and patients spend far more time crisis free than in its painful throes. This suggests that an unstable physiologic balance exists between steady state sickle cell disease (SCD) and the crisis state and if this is so a therapeutic nudge during a crisis may help to terminate it. Annexin V may be able to provide this push. The phosphatidylserine (PS) molecules normally appear on the surface of senescent erythrocytes where they are recognized by macrophages and rapidly removed so that normally only about 1% are present in the circulation but in SCD 30-40% are prematurely senescent and their removal is delayed. The PS+ sickle erythrocytes remaining in the circulation adhere to the endothelium and their exposed PS acts as a platform for the initiation of the coagulation cascade that is responsible for clot propagation. Annexin V's great affinity for PS allows it to bond to it forming a shield that blocks both of these actions suggesting that its therapeutic administration during a sickle crisis may be able to hasten its termination. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

Early embryonic brain development in rats requires the trophic influence of cerebrospinal fluid.

PubMed

Martin, C; Alonso, M I; Santiago, C; Moro, J A; De la Mano, A; Carretero, R; Gato, A

2009-11-01

Cerebrospinal fluid has shown itself to be an essential brain component during development. This is particularly evident at the earliest stages of development where a lot of research, performed mainly in chick embryos, supports the evidence that cerebrospinal fluid is involved in different mechanisms controlling brain growth and morphogenesis, by exerting a trophic effect on neuroepithelial precursor cells (NPC) involved in controlling the behaviour of these cells. Despite it being known that cerebrospinal fluid in mammals is directly involved in corticogenesis at fetal stages, the influence of cerebrospinal fluid on the activity of NPC at the earliest stages of brain development has not been demonstrated. Here, using "in vitro" organotypic cultures of rat embryo brain neuroepithelium in order to expose NPC to or deprive them of cerebrospinal fluid, we show that the neuroepithelium needs the trophic influence of cerebrospinal fluid to undergo normal rates of cell survival, replication and neurogenesis, suggesting that NPC are not self-sufficient to induce their normal activity. This data shows that cerebrospinal fluid is an essential component in chick and rat early brain development, suggesting that its influence could be constant in higher vertebrates.

Normal saline is associated with increased sickle red cell stiffness and prolonged transit times in a microfluidic model of the capillary system.

PubMed

Carden, Marcus A; Fay, Meredith; Sakurai, Yumiko; McFarland, Brynn; Blanche, Sydney; DiPrete, Caleb; Joiner, Clinton H; Sulchek, Todd; Lam, Wilbur A

2017-07-01

Vaso-occlusive crisis (VOC) is a complex process that occurs in patients with sickle cell disease (SCD) and is often associated with pain and urgent hospitalization. A major instigator of VOC is microvascular obstruction by pathologically stiffened sickle red blood cells (RBCs), and thus, therapy relies heavily on optimizing intravenous fluid (IVF) hydration to increase RBC deformability. However, no evidence-based guidelines regarding the choice of IVF currently exist. We therefore analyzed alterations in biomechanical properties of sickle RBCs isolated from patients with homozygous SCD (hemoglobin SS) after exposure to different osmolarities of clinical IVF formulations. Atomic force microscopy (AFM) was used to assess stiffness of RBCs after exposure to different IVFs. A microfluidic model of the human capillary system was used to assess transit time (TT) and propensity to occlusion after exposure to the different IVF formulations. Sickle RBCs exposed to normal saline (NS) had increased stiffness, TTs, and propensity to microchannel occlusion compared to other osmolarities. NS, an IVF formulation often used to treat patients with SCD during VOC, may induce localized microvascular obstruction due to alterations of sickle RBC biomechanical properties. © 2017 John Wiley & Sons Ltd.

[Effect of Guilingji Capsule on the fertility, liver functions, and serum LDH of male SD rats exposed by 900 mhz cell phone].

PubMed

Ma, Hui-Rong; Li, Yuan-Yuan; Luo, Ya-Ping; Ma, Xue-Lian; Gong, Zhi-Qiang

2014-04-01

To observe the effect of Guilingji Capsule (GC) on the fertility, liver functions, and serum lactate dehydrogenase (LDH) of adult male SD rats exposed by 900 MHz cell phone. Totally 18 adult male SD rats and 36 adult female rats in child-bearing period were selected and randomly divided into three groups according to weight equilibrium principle, i.e., the normal group, the radiated group, and the GC group, 6 males and 12 females in each group. Male rats in the normal group and all female rats were not radiated. Male rats in the radiated group and the GC group received radiation for 4 h per day, lasting for 18 successive days. Rats in the GC group received GC suspension at the daily dose of 0. 15 g/kg by gastrogavage at the same time. Equal volume of normal saline was administrated to other male rats. Then male rats were mated with corresponding female rats from the 14th radiation night to the 18th radiation night in the ratio of 1:2. Male rats were killed following on the next morning of ending the radiation. Female rats were normally fed and then killed before delivery. The pregnant outcomes of female rats in responding groups (the rates of pregnancy and the number of death fetus, birth weight, body length, and tail length) were observed and compared. Serum alanine aminotransferase (ALT), aspartate transferase (AST), AST/ALT, and LDH levels of the male rats were detected by colorimetry. Histological and morphological changes of liver were observed by HE staining. Compared with the normal group, the pregnancy rates of female rats decreased and the number of death fetus increased, the serum LDH level obviously increased in the radiated group (P < 0.05). Serum levels of ALT, AST, and AST/ALT were no significantly changed in the radiated group. The hepatocyte nuclear atrophy and cytoplasm vacuolar degeneration appeared. Compared with the radiated group, the pregnancy rates increased, the number of death fetus dropped, and the serum level of LDH decreased in the GC group (P < 0.05). There was no obvious change in serum levels of ALT, AST, or AST/ALT. The hepatocyte nuclear atrophy and cytoplasm vacuolar degeneration were significantly attenuated. The histomorphological structures recovered to normal basically in the GC group. The pregnancy rates could be decreased, the number of death fetus increased, histomorphological structures abnormal, and serum LDH level increased by exposure toy GSM 900 MHz cell phone. GC could prevent and treat the aforesaid lesion. But there was no statistical difference in serum ALT or AST levels.

Comparative Aging Study of Organic Solar Cells Utilizing Polyaniline and PEDOT:PSS as Hole Transport Layers.

PubMed

Abdulrazzaq, Omar; Bourdo, Shawn E; Woo, Myungwu; Saini, Viney; Berry, Brian C; Ghosh, Anindya; Biris, Alexandru S

2015-12-23

The aging effect on P3HT:PCBM organic solar cells was investigated with camphorsulfonic doped polyaniline (PANI:CSA) or poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) used as the hole transport layer (HTL). The cells were encapsulated and exposed to a continuous normal atmosphere on a dark shelf and then characterized intermittently for more than two years. The photovoltaic results revealed that the cells with PSS HTL showed better initial results than the cells with PANI:CSA HTL. Over time, PSS-based cells exhibited faster degradation than PANI:CSA-based cells, where the average efficiency of six cells dropped to zero in less than one and a half years. On the other hand, PANI:CSA-based cells exhibited a much more stable performance with an average efficiency drop of only 15% of their initial values after one and a half years and 63% after two years. A single-diode model was utilized to fit the experimental data with the theoretical curve to extract the diode parameters, such as the ideality factor, to explain the effect of aging on the diode's performance.

Moderate plasma activated media suppresses proliferation and migration of MDCK epithelial cells

NASA Astrophysics Data System (ADS)

Mohades, Soheila; Laroussi, Mounir; Maruthamuthu, Venkat

2017-05-01

Low-temperature plasma has been shown to have diverse biomedical uses, including its applications in cancer and wound healing. One recent approach in treating mammalian cells with plasma is through the use of plasma activated media (PAM), which is produced by exposing cell culture media to plasma. While the adverse effects of PAM treatment on cancerous epithelial cell lines have been recently studied, much less is known about the interaction of PAM with normal epithelial cells. In this paper, non-cancerous canine kidney MDCK (Madin-Darby Canine Kidney) epithelial cells were treated by PAM and time-lapse microscopy was used to directly monitor their proliferation and random migration upon treatment. While longer durations of PAM treatment led to cell death, we found that moderate levels of PAM treatment inhibited proliferation in these epithelial cells. We also found that PAM treatment reduced random cell migration within epithelial islands. Immunofluorescence staining showed that while there were no major changes in the actin/adhesion apparatus, there was a significant change in the nuclear localization of proliferation marker Ki-67, consistent with our time-lapse results.

Upregulated expression of La ribonucleoprotein domain family member 6 and collagen type I gene following water-filtered broad-spectrum near-infrared irradiation in a 3-dimensional human epidermal tissue culture model as revealed by microarray analysis.

PubMed

Tanaka, Yohei; Nakayama, Jun

2018-05-01

Water-filtered broad-spectrum near-infrared irradiation can induce various biological effects, as our previous clinical, histological, and biochemical investigations have shown. However, few studies that examined the changes thus induced in gene expression. The aim was to investigate the changes in gene expression in a 3-dimensional reconstructed epidermal tissue culture exposed to water-filtered broad-spectrum near-infrared irradiation. DNA microarray and quantitative real-time polymerase chain reaction (PCR) analysis was used to assess gene expression levels in a 3-dimensional reconstructed epidermal model composed of normal human epidermal cells exposed to water-filtered broad-spectrum near-infrared irradiation. The water filter allowed 1000-1800 nm wavelengths and excluded 1400-1500 nm wavelengths, and cells were exposed to 5 or 10 rounds of near-infrared irradiation at 10 J/cm 2 . A DNA microarray with over 50 000 different probes showed 18 genes that were upregulated or downregulated by at least twofold after irradiation. Quantitative real-time PCR revealed that, relative to control cells, the gene encoding La ribonucleoprotein domain family member 6 (LARP6), which regulates collagen expression, was significantly and dose-dependently upregulated (P < 0.05) by water-filtered broad-spectrum near-infrared exposure. Gene encoding transcripts of collagen type I were significantly upregulated compared with controls (P < 0.05). This study demonstrates the ability of water-filtered broad-spectrum near-infrared irradiation to stimulate the production of type I collagen. © 2017 The Australasian College of Dermatologists.

Reconstituted normal human breast in nude mice: effect of host pregnancy environment and human chorionic gonadotropin on proliferation.

PubMed

Popnikolov, N; Yang, J; Liu, A; Guzman, R; Nandi, S

2001-03-01

The proliferation of normal human breast epithelial cells in women is highest during the first trimester of pregnancy. In an attempt to analyze this hormonal environment in a model system, the effect of host mouse pregnancy and the administration of human chorionic gonadotropin (hCG) were assessed in normal human breast epithelial cells transplanted into athymic nude mice. Human breast epithelial cells, dissociated from reduction mammoplasty specimens and embedded inside the extracellular matrices comprised of collagen gel and Matrigel, were transplanted into nude mice. Proliferation was measured in vivo by BrdU labeling followed by immunostaining of sections from recovered gels in response to an altered hormonal environment of the host animal. The host animal was mated to undergo pregnancy and the complex hormonal environment of the host animal pregnancy stimulated growth of transplanted human cells. This effect increased with progression of pregnancy and reached the maximum during late pregnancy prior to parturition. In order to determine whether additional stimulation could be achieved, the transplanted human cells were exposed to a second cycle of host mouse pregnancy by immediately mating the animal after parturition. This additional exposure of host mouse pregnancy did not result in further increase of proliferation. The effect of hCG administration on transplanted human cells was also tested, since hCG level is highest during the first trimester of human pregnancy and coincides with the maximal breast cell proliferation. Administration of hCG alone stimulated proliferation of human cells in a dose-dependent manner, and could further enhance stimulation achieved with estrogen. The host mouse mammary gland also responded to hCG treatment resulting in increased branching and lobulo-alveolar development. However, the hCG effect on both human and mouse cells was dependent on intact ovary since the stimulation did not occur in ovariectomized animals. Although hCG receptor transcripts were detected in human breast epithelial cells, raising the possibility of a direct mitogenic action, the hCG effect observed in this study may have been mediated via the ovary by increased secretion of ovarian steroids. In summary, using our in vivo nude mice system, the proliferation of normal human breast epithelial cells could be stimulated by host mouse pregnancy and by administration of hCG.

Inter-relationship between testicular dysgenesis and Leydig cell function in the masculinization programming window in the rat.

PubMed

van den Driesche, Sander; Kolovos, Petros; Platts, Sophie; Drake, Amanda J; Sharpe, Richard M

2012-01-01

The testicular dysgenesis syndrome (TDS) hypothesis proposes that maldevelopment of the testis, irrespective of cause, leads to malfunction of the somatic (Leydig, Sertoli) cells and consequent downstream TDS disorders. Studies in rats exposed in utero to di(n-butyl) phthalate (DBP) have strongly supported the TDS concept, but so far no direct evidence has been produced that links dysgenesis per se to somatic cell dysfunction, in particular to androgen production/action during the 'masculinization programming window' (MPW; e15.5-e18.5). Normal reproductive tract development and anogenital distance (AGD) are programmed within the MPW, and TDS disorders arise because of deficiencies in this programming. However, DBP-induced focal testicular dysgenesis (Leydig cell aggregation, ectopic Sertoli cells, malformed seminiferous cords) is not evident until after the MPW. Therefore, we used AGD as a read-out of androgen exposure in the MPW, and investigated if this measure was related to objectively quantified dysgenesis (Leydig cell aggregation) at e21.5 in male fetuses exposed to vehicle, DBP (500 or 750 mg/kg/day) or the synthetic glucocorticoid dexamethasone (Dex; alone or plus DBP-500) from e15.5-e18.5 (MPW), e13.5-e20.5 or e19.5-e20.5 (late window). Dysgenesis was found only in animals exposed to DBP during the MPW, and was negatively correlated (R² = -0.5) with AGD at e21.5 and at postnatal day 8, irrespective of treatment period. Dysgenesis was also negatively correlated (R² = -0.5) with intratesticular testosterone (ITT) at e21.5, but only when treatments in short windows (MPW, late window) were excluded; the same was true for correlation between AGD and ITT. We conclude that AGD, reflecting Leydig cell function solely within the MPW, is strongly related to focal dysgenesis. Our results point to this occurring because of a common early mechanism, targeted by DBP that determines both dysgenesis and early (during the MPW) fetal Leydig cell dysfunction. The findings provide strong validation of the TDS hypothesis.

Comparative study of the photodynamic effect in tumor and nontumor animal cell lines

NASA Astrophysics Data System (ADS)

Stoykova, Elena V.; Alexandrova, R.; Shurulinkov, Stanislav; Sabotinov, O.; Minchev, Georgi

2004-09-01

In this study we evaluate the cytotoxicity of two photosensitisers with absorption peaks in the green and red part of the spectrum on animal cell lines. The cytotoxicity assessment was performed for a tumor cell line LSCC-SF-Mc29, obtained from a transplantable chicken hepatoma induced by the myelocytomatosis virus Mc29, a tumor line LSR-SF-SR, obtained from a transplantable sarcoma in rat induced by Rous sarcoma virus strain Schmidt-Ruppin and for normal mouse and bovine cell lines. Up to now the effect of the photodynamic therapy on virus-induced cancers has not been clarified. The cells were treated with 5,10,15,20 - tetra (4-sulfophenyl) porphyrin with main absorption peak at 519 nm and a dye activated with a red light. The cells were seeded in 96-well plates at 2 x 104 cells/well. The cells were exposed to irradiation from a pulsed CuBr vapor laser at 510.6 nm and 578.2 nm and exposure rate 50 mW/cm2, from an Ar-ion laser at 514 nm and 1 mW/cm2 and to 655 nm-irradiation from a semiconductor laser at 10 mW/cm2. The biological activity of the tested compounds was measured by the neutral red uptake cytotoxicity test. The light dose-response curves and light exposures that ensure 50% drop in the treated cells viability in comparison with the cells grown in non-modified medium were obtained for each cell line. The cytotoxic effect of both photosensitisers is most distinguished for the tumor line LSCC-SF-Mc29. The 2-4 times higher viability of the normal cell lines in comparison with the tumor lines is established. The bovine cell lines are more vulnerable than the mouse lines.

3,4-Methylenedioxymethamphetamine (MDMA) alters acute gammaherpesvirus burden and limits Interleukin 27 responses in a mouse model of viral infection

PubMed Central

Nelson, Daniel A.; Singh, Sam J.; Young, Amy B.; Tolbert, Melanie D.; Bost, Kenneth L.

2011-01-01

Aims To test whether 3,4-methylenedioxymethamphetamine (MDMA, “Ecstasy”) abuse might increase the susceptibility, or alter the immune response, to murine gammaherpesvirus 68 (HV-68) and/or bacterial lipopolysaccharide. Methods Groups of experimental and control mice were subjected to three day binges of MDMA, and the effect of this drug abuse on acute and latent HV-68 viral burden were assessed. In vitro and in vivo studies were also performed to assess the MDMA effect on IL-27 expression in virally infected or LPS-exposed macrophages and dendritic cells, and latently infected animals, exposed to this drug of abuse. Results Acute viral burden was significantly increased in MDMA-treated mice when compared to controls. However the latent viral burden, and physiological and behavioral responses were not altered in infected mice despite repeated bingeing with MDMA. MDMA could limit the IL-27 response of HV-68 infected or LPS-exposed macrophages and dendritic cells in vitro and in vivo, demonstrating the ability of this drug to alter normal cytokine responses in the context of a viral infection and/or a TLR4 agonist. Conclusion MDMA bingeing could alter the host’s immune response resulting in greater acute viral replication and reductions in the production of the cytokine, IL-27 during immune responses. PMID:21269783

Fusion proteins comprising annexin V and Kunitz protease inhibitors are highly potent thrombogenic site-directed anticoagulants

PubMed Central

Chen, Hsiu-Hui; Vicente, Cristina P.; He, Li; Tollefsen, Douglas M.; Wun, Tze-Chein

2005-01-01

The anionic phospholipid, phosphatidyl-l-serine (PS), is sequestered in the inner layer of the plasma membrane in normal cells. Upon injury, activation, and apoptosis, PS becomes exposed on the surfaces of cells and sheds microparticles, which are procoagulant. Coagulation is initiated by formation of a tissue factor/factor VIIa complex on PS-exposed membranes and propagated through the assembly of intrinsic tenase (factor VIIIa/factor IXa), prothrombinase (factor Va/factor Xa), and factor XIa complexes on PS-exposed activated platelets. We constructed a novel series of recombinant anticoagulant fusion proteins by linking annexin V (ANV), a PS-binding protein, to the Kunitz-type protease inhibitor (KPI) domain of tick anticoagulant protein, an aprotinin mutant (6L15), amyloid β-protein precursor, or tissue factor pathway inhibitor. The resulting ANV-KPI fusion proteins were 6- to 86-fold more active than recombinant tissue factor pathway inhibitor and tick anticoagulant protein in an in vitro tissue factor–initiated clotting assay. The in vivo antithrombotic activities of the most active constructs were 3- to 10-fold higher than that of ANV in a mouse arterial thrombosis model. ANV-KPI fusion proteins represent a new class of anticoagulants that specifically target the anionic membrane-associated coagulation enzyme complexes present at sites of thrombogenesis and are potentially useful as antithrombotic agents. PMID:15677561

Maternal mobile phone exposure alters intrinsic electrophysiological properties of CA1 pyramidal neurons in rat offspring.

PubMed

Razavinasab, Moazamehosadat; Moazzami, Kasra; Shabani, Mohammad

2016-06-01

Some studies have shown that exposure to electromagnetic field (EMF) may result in structural damage to neurons. In this study, we have elucidated the alteration in the hippocampal function of offspring Wistar rats (n = 8 rats in each group) that were chronically exposed to mobile phones during their gestational period by applying behavioral, histological, and electrophysiological tests. Rats in the EMF group were exposed to 900 MHz pulsed-EMF irradiation for 6 h/day. Whole cell recordings in hippocampal pyramidal cells in the mobile phone groups did show a decrease in neuronal excitability. Mobile phone exposure was mostly associated with a decrease in the number of action potentials fired in spontaneous activity and in response to current injection in both male and female groups. There was an increase in the amplitude of the afterhyperpolarization (AHP) in mobile phone rats compared with the control. The results of the passive avoidance and Morris water maze assessment of learning and memory performance showed that phone exposure significantly altered learning acquisition and memory retention in male and female rats compared with the control rats. Light microscopy study of brain sections of the control and mobile phone-exposed rats showed normal morphology.Our results suggest that exposure to mobile phones adversely affects the cognitive performance of both female and male offspring rats using behavioral and electrophysiological techniques. © The Author(s) 2014.

Cystic Fibrosis Transmembrane Conductance Regulator Controls Lung Proteasomal Degradation and Nuclear Factor-κB Activity in Conditions of Oxidative Stress

PubMed Central

Boncoeur, Emilie; Roque, Telma; Bonvin, Elise; Saint-Criq, Vinciane; Bonora, Monique; Clement, Annick; Tabary, Olivier; Henrion-Caude, Alexandra; Jacquot, Jacky

2008-01-01

Cystic fibrosis is a lethal inherited disorder caused by mutations in a single gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, resulting in progressive oxidative lung damage. In this study, we evaluated the role of CFTR in the control of ubiquitin-proteasome activity and nuclear factor (NF)-κB/IκB-α signaling after lung oxidative stress. After a 64-hour exposure to hyperoxia-mediated oxidative stress, CFTR-deficient (cftr−/−) mice exhibited significantly elevated lung proteasomal activity compared with wild-type (cftr+/+) animals. This was accompanied by reduced lung caspase-3 activity and defective degradation of NF-κB inhibitor IκB-α. In vitro, human CFTR-deficient lung cells exposed to oxidative stress exhibited increased proteasomal activity and decreased NF-κB-dependent transcriptional activity compared with CFTR-sufficient lung cells. Inhibition of the CFTR Cl− channel by CFTRinh-172 in the normal bronchial immortalized cell line 16HBE14o− increased proteasomal degradation after exposure to oxidative stress. Caspase-3 inhibition by Z-DQMD in CFTR-sufficient lung cells mimicked the response profile of increased proteasomal degradation and reduced NF-κB activity observed in CFTR-deficient lung cells exposed to oxidative stress. Taken together, these results suggest that functional CFTR Cl− channel activity is crucial for regulation of lung proteasomal degradation and NF-κB activity in conditions of oxidative stress. PMID:18372427

Protocol for vital dye staining of corneal endothelial cells.

PubMed

Park, Sunju; Fong, Alan G; Cho, Hyung; Zhang, Cheng; Gritz, David C; Mian, Gibran; Herzlich, Alexandra A; Gore, Patrick; Morganti, Ashley; Chuck, Roy S

2012-12-01

To describe a step-by-step methodology to establish a reproducible staining protocol for the evaluation of human corneal endothelial cells. Four procedures were performed to determine the best protocol. (1) To determine the optimal trypan blue staining method, goat corneas were stained with 4 dilutions of trypan blue (0.4%, 0.2%, 0.1%, and 0.05%) and 1% alizarin red. (2) To determine the optimal alizarin red staining method, goat corneas were stained with 2 dilutions of alizarin red (1% and 0.5%) and 0.2% trypan blue. (3) To ensure that trypan blue truly stains damaged cells, goat corneas were exposed to either 3% hydrogen peroxide or to balanced salt solution, and then stained with 0.2% trypan blue and 0.5% alizarin red. (4) Finally, fresh human corneal buttons were examined; 1 group was stained with 0.2% trypan blue and another group with 0.4% trypan blue. For the 4 procedures performed, the results are as follows: (1) trypan blue staining was not observed in any of the normal corneal samples; (2) 0.5% alizarin red demonstrated sharper cell borders than 1% alizarin red; (3) positive trypan blue staining was observed in the hydrogen peroxide exposed tissue in damaged areas; (4) 0.4% trypan blue showed more distinct positive staining than 0.2% trypan blue. We were able to determine the optimal vital dye staining conditions for human corneal endothelial cells using 0.4% trypan blue and 0.5% alizarin red.

DNA damage in oral cancer and normal cells induced by nitrogen atmospheric pressure plasma jets

NASA Astrophysics Data System (ADS)

Han, Xu; Kapaldo, James; Liu, Yueying; Stack, M. Sharon; Ptasinska, Sylwia

2015-09-01

Nitrogen atmospheric pressure plasma jets (APPJs) have been shown to effectively induce DNA double strand breaks in SCC25 oral cancer cells. The APPJ source constructed in our laboratory operates based on dielectric barrier discharge. It consists of two copper electrodes alternatively wrapping around a fused silica tube with nitrogen as a feed gas. It is generally more challenging to ignite plasma in N2 atmosphere than in noble gases. However, N2 provides additional advantages such as lower costs compared to noble gases, thus this design can be beneficial for the future long-term clinical use. To compare the effects of plasma on cancer cells (SCC25) and normal cells (OKF), the cells from both types were treated at the same experimental condition for various treatment times. The effective area with different damage levels after the treatment was visualized as 3D maps. The delayed damage effects were also explored by varying the incubation times after the treatment. All of these studies are critical for a better understanding of the damage responses of cellular systems exposed to the plasma radiation, thus are useful for the development of the advanced plasma cancer therapy. The research described herein was supported by the Division of Chemical Sciences, Geosciences and Biosciences, Basic Energy Sciences, Office of Science, United States Department of Energy through Grant No. DE-FC02-04ER15533.

The expression of β3-adrenoceptors and their function in the human prostate.

PubMed

Suzuki, Takahisa; Otsuka, Atsushi; Matsumoto, Rikiya; Furuse, Hiroshi; Ozono, Seiichiro

2016-02-01

Little is known about β3-adrenoceptor (AR) expression and function in human prostate. We examined the expression and distribution of β-AR subtypes in normal prostate and benign prostatic hyperplasia (BPH) tissues, and investigated which selective β-AR subtype agonist was most involved in the relaxation of isolated human prostate strips. Messenger RNA (mRNA) expression for β1-, β2-, and β3 -ARs was investigated using reverse transcriptase-polymerase chain reactions (RT-PCR). Quantitative analysis of mRNA expression of β-AR subtypes between normal prostate and BPH tissues was performed using quantitative RT-PCR (qPCR). Distributions were examined by immunohistochemistry (IHC). Strips of human normal prostate or BPH were suspended in organ baths and exposed to isoproterenol, dobutamine, procaterol, and TRK-380 to investigate their relaxant effects on KCl-induced contractions, and their inhibitory effects on electrical field stimulation (EFS)-induced contractions. We confirmed the presence of mRNA for β1-, β2-, and β3-ARs both in normal prostate and in BPH tissues. For β3-AR, mRNA expression in BPH tissues was significantly higher than in normal prostate tissues, but there was no significant difference in β1- and β2-AR expression between normal and BPH tissues. IHC revealed differences in staining intensity between smooth muscle cells and glandular cells, with different proportions for different β-AR subtypes. Staining of β3-AR was particularly intense in smooth muscle cells as opposed to glandular cells. Isoproterenol and TRK-380 significantly decreased the tone of KCl-induced contractions of the normal prostate strips. The rank order of relaxant effects was isoproterenol > TRK-380 > procaterol > dobutamine. All selective β-AR agonists significantly decreased the amplitude of EFS-induced contractions of the normal prostate strips. The rank order of inhibitory effects was isoproterenol > dobutamine >TRK-380 > procaterol. In BPH strips, all selective β-AR agonists showed no significant relaxant or inhibitory effects on KCl- or EFS-induced contractions. β3 -AR is abundant in human prostate smooth muscle, whose relaxation is mediated by β1- and β3-AR stimulation. β3-AR agonists may have clinical use in the treatment of male non-BPH patients or neurogenic bladder patients with voiding dysfunction. © 2015 Wiley Periodicals, Inc.

Assessment of central auditory processing in a group of workers exposed to solvents.

PubMed

Fuente, Adrian; McPherson, Bradley; Muñoz, Verónica; Pablo Espina, Juan

2006-12-01

Despite having normal hearing thresholds and speech recognition thresholds, results for central auditory tests were abnormal in a group of workers exposed to solvents. Workers exposed to solvents may have difficulties in everyday listening situations that are not related to a decrement in hearing thresholds. A central auditory processing disorder may underlie these difficulties. To study central auditory processing abilities in a group of workers occupationally exposed to a mix of organic solvents. Ten workers exposed to a mix of organic solvents and 10 matched non-exposed workers were studied. The test battery comprised pure-tone audiometry, tympanometry, acoustic reflex measurement, acoustic reflex decay, dichotic digit, pitch pattern sequence, masking level difference, filtered speech, random gap detection and hearing-in-noise tests. All the workers presented normal hearing thresholds and no signs of middle ear abnormalities. Workers exposed to solvents had lower results in comparison with the control group and previously reported normative data, in the majority of the tests.

Effect of brain-derived neurotrophic factor (BDNF) on sperm quality of normozoospermic men.

PubMed

Safari, Hassan; Khanlarkhani, Neda; Sobhani, Aligholi; Najafi, Atefeh; Amidi, Fardin

2017-07-05

The neurotrophin family of proteins and their receptors act as important proliferative and pro-survival factors in differentiation of nerve cells and are thought to play key roles in the development of reproductive tissues and normal function of spermatozoa. The objective of the present study was to evaluate the effect of Brain-Derived Neurotrophic Factor (BDNF) on the sperm viability and motility, lipid peroxidation (LPO), mitochondrial activity and concentration of leptin, nitric oxide (NO) and insulin in normozoospermic men. Semen samples from 20 normozoospermic men were divided into three groups: (i) control, (ii) BDNF and (iii) BDNF + K252a. BDNF and K252a were added in the dose of 0.133 and 0.1 nM, respectively. Viability was assessed by eosin-nigrosin staining technique, and motility was observed by microscopy. NO concentration and mitochondrial activity were measured with flow cytometry, and LPO was analyzed using enzyme-linked immunosorbent assay (ELISA) kits. Results showed that exogenous BDNF at 0.133 nM could significantly (p < 0.05) influence viability, motility, NO concentration, mitochondrial activity and LPO content. Secretions of insulin and leptin by human sperm were increased in cells exposed to the exogenous BDNF, whereas viability, mitochondrial activity and insulin and leptin secretions were decreased in cells exposed to the K252.

Exosomes from human colorectal cancer induce a tumor-like behavior in colonic mesenchymal stromal cells

PubMed Central

Lugini, Luana; Valtieri, Mauro; Federici, Cristina; Cecchetti, Serena; Meschini, Stefania; Condello, Maria; Signore, Michele; Fais, Stefano

2016-01-01

Background Cancer cells, including colorectal cancer ones (CRC), release high amounts of nanovesicles (exosomes), delivering biochemical messages for paracrine or systemic crosstalk. Mesenchymal stromal cells (MSCs) have been shown to play contradicting roles in tumor progression. Results CRC exosomes induce in cMSCs: i) atypical morphology, higher proliferation, migration and invasion; ii) formation of spheroids; iii) an acidic extracellular environment associated with iv) a plasma membrane redistribution of vacuolar H+-ATPase and increased expression of CEA. Colon cancer derived MSCs, which were isolated from tumor masses, produce umbilicated spheroids, a future frequently observed in the inner core of rapidly growing tumors and recapitulate the changes observed in normal colonic MSCs exposed to CRC exosomes. Materials and Methods Tissue specific colonic (c)MSCs were exposed to primary or metastatic CRC exosomes and analysed by light and electron microscopy, proliferation in 2D and 3D cultures, migration and invasion assays, Western blot and confocal microscopy for vacuolar H+-ATPase expression. Conclusions CRC exosomes are able to induce morphological and functional changes in colonic MSCs, which may favour tumor growth and its malignant progression. Our results suggest that exosomes are actively involved in cancer progression and that inhibiting tumor exosome release may represent a way to interfere with cancer. PMID:27418137

Exosomes from human colorectal cancer induce a tumor-like behavior in colonic mesenchymal stromal cells.

PubMed

Lugini, Luana; Valtieri, Mauro; Federici, Cristina; Cecchetti, Serena; Meschini, Stefania; Condello, Maria; Signore, Michele; Fais, Stefano

2016-08-02

Cancer cells, including colorectal cancer ones (CRC), release high amounts of nanovesicles (exosomes), delivering biochemical messages for paracrine or systemic crosstalk. Mesenchymal stromal cells (MSCs) have been shown to play contradicting roles in tumor progression. CRC exosomes induce in cMSCs: i) atypical morphology, higher proliferation, migration and invasion; ii) formation of spheroids; iii) an acidic extracellular environment associated with iv) a plasma membrane redistribution of vacuolar H+-ATPase and increased expression of CEA. Colon cancer derived MSCs, which were isolated from tumor masses, produce umbilicated spheroids, a future frequently observed in the inner core of rapidly growing tumors and recapitulate the changes observed in normal colonic MSCs exposed to CRC exosomes. Tissue specific colonic (c)MSCs were exposed to primary or metastatic CRC exosomes and analysed by light and electron microscopy, proliferation in 2D and 3D cultures, migration and invasion assays, Western blot and confocal microscopy for vacuolar H+-ATPase expression. CRC exosomes are able to induce morphological and functional changes in colonic MSCs, which may favour tumor growth and its malignant progression. Our results suggest that exosomes are actively involved in cancer progression and that inhibiting tumor exosome release may represent a way to interfere with cancer.

Acute cardiovascular toxicity of sterilizers, PHMG, and PGH: severe inflammation in human cells and heart failure in zebrafish.

PubMed

Kim, Jae-Yong; Kim, Hak Hyeon; Cho, Kyung-Hyun

2013-06-01

In 2011, dozens of children and pregnant women in Korea died by exposure to sterilizer for household humidifier, such as Oxy(®) and Cefu(®). Until now, however, it remains unknown how the sterilizer affect the human health to cause the acute deaths. To find its toxicity for organ, we investigated the putative toxicity of the sterilizer in the cardiovascular system. The sterilizers, polyhexamethylene guanidine phosphate (PHMG, Cefu(®)), and oligo-[2-(2-ethoxy)-ethoxyethyl)-guanidinium-chloride (PGH, Oxy(®)) were treated to human lipoproteins, macrophages, and dermal fibroblast cells. The PGH and PHMG at normal dosages caused severe atherogenic process in human macrophages, cytotoxic effect, and aging in human dermal cell. Zebrafish embryos, which were exposed to the sterilizer, showed early death with acute inflammation and attenuated developmental speed. All zebrafish exposed to the working concentration of PHMG (final 0.3 %) and PGH (final 10 mM) died within 70 min and displayed acute increases in serum triacylglycerol level and fatty liver induction. The dead zebrafish showed severe accumulation of fibrous collagen in the bulbous artery of the heart with elevation of reactive oxygen species. In conclusion, the sterilizers showed acute toxic effect in blood circulation system, causing by severe inflammation, atherogenesis, and aging, with embryo toxicity.

Neutron Exposures in Human Cells: Bystander Effect and Relative Biological Effectiveness

PubMed Central

Seth, Isheeta; Schwartz, Jeffrey L.; Stewart, Robert D.; Emery, Robert; Joiner, Michael C.; Tucker, James D.

2014-01-01

Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting a near-monoenergetic 50.5 MeV proton beam at a Be target (17 MeV average neutron energy), and irradiated-cell conditioned media (ICCM) was transferred to unirradiated cells. The cytokinesis-block micronucleus assay was used to quantify genetic damage in radiation-naïve cells exposed to ICCM from cultures that received 0 (control), 0.5, 1, 1.5, 2, 3 or 4 Gy neutrons. Cells grown in ICCM from irradiated cells showed no significant increase in the frequencies of micronuclei or nucleoplasmic bridges compared to cells grown in ICCM from sham irradiated cells for either cell line. However, the neutron beam has a photon dose-contamination of 5%, which may modulate a neutron-induced bystander effect. To determine whether these low doses of contaminating photons can induce a bystander effect, cells were irradiated with cobalt-60 at doses equivalent to the percent contamination for each neutron dose. No significant increase in the frequencies of micronuclei or bridges was observed at these doses of photons for either cell line when cultured in ICCM. As expected, high doses of photons induced a clear bystander effect in both cell lines for micronuclei and bridges (p<0.0001). These data indicate that neutrons do not induce a bystander effect in these cells. Finally, neutrons had a relative biological effectiveness of 2.0±0.13 for micronuclei and 5.8±2.9 for bridges compared to cobalt-60. These results may be relevant to radiation therapy with fast neutrons and for regulatory agencies setting standards for neutron radiation protection and safety. PMID:24896095

Neutron exposures in human cells: bystander effect and relative biological effectiveness.

PubMed

Seth, Isheeta; Schwartz, Jeffrey L; Stewart, Robert D; Emery, Robert; Joiner, Michael C; Tucker, James D

2014-01-01

Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting a near-monoenergetic 50.5 MeV proton beam at a Be target (17 MeV average neutron energy), and irradiated-cell conditioned media (ICCM) was transferred to unirradiated cells. The cytokinesis-block micronucleus assay was used to quantify genetic damage in radiation-naïve cells exposed to ICCM from cultures that received 0 (control), 0.5, 1, 1.5, 2, 3 or 4 Gy neutrons. Cells grown in ICCM from irradiated cells showed no significant increase in the frequencies of micronuclei or nucleoplasmic bridges compared to cells grown in ICCM from sham irradiated cells for either cell line. However, the neutron beam has a photon dose-contamination of 5%, which may modulate a neutron-induced bystander effect. To determine whether these low doses of contaminating photons can induce a bystander effect, cells were irradiated with cobalt-60 at doses equivalent to the percent contamination for each neutron dose. No significant increase in the frequencies of micronuclei or bridges was observed at these doses of photons for either cell line when cultured in ICCM. As expected, high doses of photons induced a clear bystander effect in both cell lines for micronuclei and bridges (p<0.0001). These data indicate that neutrons do not induce a bystander effect in these cells. Finally, neutrons had a relative biological effectiveness of 2.0 ± 0.13 for micronuclei and 5.8 ± 2.9 for bridges compared to cobalt-60. These results may be relevant to radiation therapy with fast neutrons and for regulatory agencies setting standards for neutron radiation protection and safety.

Genetic modification of human mesenchymal stem cells helps to reduce adiposity and improve glucose tolerance in an obese diabetic mouse model.

PubMed

Sen, Sabyasachi; Domingues, Cleyton C; Rouphael, Carol; Chou, Cyril; Kim, Chul; Yadava, Nagendra

2015-12-09

Human mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into fat, muscle, bone and cartilage cells. Exposure of subcutaneous abdominal adipose tissue derived AD-MSCs to high glucose (HG) leads to superoxide accumulation and up-regulation of inflammatory molecules. Our aim was to inquire how HG exposure affects MSCs differentiation and whether the mechanism is reversible. We exposed human adipose tissue derived MSCs to HG (25 mM) and compared it to normal glucose (NG, 5.5 mM) exposed cells at 7, 10 and 14 days. We examined mitochondrial superoxide accumulation (Mitosox-Red), cellular oxygen consumption rate (OCR, Seahorse) and gene expression. HG increased reactive superoxide (ROS) accumulation noted by day 7 both in cytosol and mitochondria. The OCR between the NG and HG exposed groups however did not change until 10 days at which point OCR of HG exposed cells were reduced significantly. We noted that HG exposure upregulated mRNA expression of adipogenic (PPARG, FABP-4, CREBP alpha and beta), inflammatory (IL-6 and TNF alpha) and antioxidant (SOD2 and Catalase) genes. Next, we used AdSOD2 to upregulate SOD2 prior to HG exposure and thereby noted reduction in superoxide generation. SOD2 upregulation helped reduce mRNA over-expression of PPARG, FABP-4, IL-6 and TNFα. In a series of separate experiments, we delivered the eGFP and SOD2 upregulated MSCs (5 days post ex-vivo transduction) and saline intra-peritoneally (IP) to obese diabetic (db/db) mice. We confirmed homing-in of eGFP labeled MSCs, delivered IP, to different inflamed fat pockets, particularly omental fat. Mice receiving SOD2-MSCs showed progressive reduction in body weight and improved glucose tolerance (GTT) at 4 weeks, post MSCs transplantation compared to the GFP-MSC group (control). High glucose evokes superoxide generation, OCR reduction and adipogenic differentiation. Mitochondrial superoxide dismutase upregulation quenches excess superoxide and reduces adipocyte inflammation. Delivery of superoxide dismutase (SOD2) using MSCs as a gene delivery vehicle reduces inflammation and improves glucose tolerance in vivo. Suppression of superoxide production and adipocyte inflammation using mitochondrial superoxide dismutase may be a novel and safe therapeutic tool to combat hyperglycemia mediated effects.

Mechanisms of mucus release in exposed canine gastric mucosa.

PubMed

Zalewsky, C A; Moody, F G

1979-10-01

Mucus release was studied in the exposed gastric mucosa of anesthetized fasted dogs using scanning and transmission microscopy as well as histochemical and autoradiographic techniques. Under unstimulated conditions, the gastric epithelium was composed of both nonsecreting and mucus-secreting epithelial cells, with the former being predominant. Nonsecreting cells were characterized by an intact apical mucus package of granules and a continuous plasma membrane. The secreting mucus cell population was found in the foveolar (pit region) as well as interfoveolar areas. Three mechanisms of mucus release were observed: (a) exocytosis, (b) apical expulsion, and (c) cell exfoliation. Evidence for exocytosis was found in all mucus cells, especially in the sulfated glycoprotein-rich foveolar cells. Exocytosis involved only a few granules at a time; this mode of secretion is likely slow and continuous. In contrast, apical expulsion resulted in an explosive release of the entire apical mucus package followed by in situ degeneration of the cell itself. This occurred in the oldest cells forming mucosal crests in the interfoveolar area, whose mucus predominantly stains for neutral glycoproteins. Cell exfoliation, in which the entire cell was extruded into the lumen, was rarely observed and may provide, in addition to apical expulsion, a second mechanism to rid the mucosa of senescent epithelial cells. Mucus secretion is a complex function of the gastric epithelium. The mechanism of secretion and the histochemically defined type of mucus secreted are variables which are dependent on the age of the cell, its position on the foveolae, and the microenvironment within the gastric lumen. The mucus-containing surface and pit cells of gastric epithelium have been described morphologically and ultrastructurally in a number of studies. These cells are highly differentiated, forming a layer which is dynamic and responsive to conditions present in the gastric lumen. Mucus cells arise from multipotent progenitor cells which differentiate in the course of migration up the gastric pits and are involved in the complex macromolecular synthesis of glycoproteins. Although mucus release occurs throughout cell life, very little attention has been given to the cellular ultrastructural changes that deal with mucus secretion. As a result, the mucus-containing surface and pit cells have been described primarily in terms of their nonsecreting functional state. Exceptions to this are a few transmission and scanning electron microscopy studies which describe loss of intact mucus granules, cell extrusion, and in situ degeneration. These previous ultrastructural studies describe cellular patterns, in both normal and injured mucosa, which we fell are related to mucus release. Because of a paucity of knowledge concerning the normal mechanisms of mucus secretion, it was the purpose of this study to define the ultrastructural changes which result in and accompany the production of mucus in canine gastric epithelium.

[Effects on blood cell numbers and cytokines of dermal application rocket kerosene in mice].

PubMed

Xu, Bingxin; Wang, Jianying; Liu, Zhiguo; Li, Chenglin; Yang, Heming; Lou, Xiaotong; Li, Jianzhong; Cui, Yan

2015-09-01

To detect the number of cells and the level of IL-2, IL-4, IL-6, IL-10, TNF-alpha, IFN-γ and IL-17 cytokines in the peripheral blood of mice exposed to rocket kerosene by skin. ICR mice were randomly divided into the normal control group and RK experimental group (400 µl×1 group). RK undiluted fuel were applied directly to the dorsal skin of the mice. In control groups were treated with sesame oil (SO). the number of blood cells were detected by automatic blood cell counter and the level of IL-2, IL-4, IL-6, IL-10, TNF-alpha, IFN-γ and IL-17 cytokines in serum were detected by using flow cytometry and BD CBA Flex set kit. Compared with the normal group, WBC and LYM had a decreasing tendency 2 h and decreased significantly 6 h, 12 h and 1 d after RK exposure (P<0.05). They increased significantly 7 d after RK exposure (P<0.05). Compared with the normal group, the level of IL-6 increased significantly 2 h, 6 h, 12 h,1 d and 3 d (P<0.05). The level of TNF-α increased significantly 2h, 3d, 5d and 7d (P<0.05). The level of IL-10 increased significantly 2 h, 6 h, 3 d, 5 d and 7 d (P<0.05). The level of IFN-γ increased significantly 6 h and 3 d (P< 0.05). The level of IL-17 significantly increased 3 d, 5 d and 7d (P<0.05). RK can change the number of immune cells, causing the immune cytokine changes in mice after RK cutaneous exposure.

Nuclear pore complex-mediated modulation of TCR signaling is required for naïve CD4+ T cell homeostasis.

PubMed

Borlido, Joana; Sakuma, Stephen; Raices, Marcela; Carrette, Florent; Tinoco, Roberto; Bradley, Linda M; D'Angelo, Maximiliano A

2018-06-01

Nuclear pore complexes (NPCs) are channels connecting the nucleus with the cytoplasm. We report that loss of the tissue-specific NPC component Nup210 causes a severe deficit of naïve CD4 + T cells. Nup210-deficient CD4 + T lymphocytes develop normally but fail to survive in the periphery. The decreased survival results from both an impaired ability to transmit tonic T cell receptor (TCR) signals and increased levels of Fas, which sensitize Nup210 -/- naïve CD4 + T cells to Fas-mediated cell death. Mechanistically, Nup210 regulates these processes by modulating the expression of Cav2 (encoding Caveolin-2) and Jun at the nuclear periphery. Whereas the TCR-dependent and CD4 + T cell-specific upregulation of Cav2 is critical for proximal TCR signaling, cJun expression is required for STAT3-dependent repression of Fas. Our results uncover an unexpected role for Nup210 as a cell-intrinsic regulator of TCR signaling and T cell homeostasis and expose NPCs as key players in the adaptive immune system.

Network analysis of genes involved in the enhancement of hyperthermia sensitivity by the knockdown of BAG3 in human oral squamous cell carcinoma cells.

PubMed

Yunoki, Tatsuya; Tabuchi, Yoshiaki; Hayashi, Atsushi; Kondo, Takashi

2016-07-01

BCL2-associated athanogene 3 (BAG3), a co-chaperone of the heat shock 70 kDa protein (HSPA) family of proteins, is a cytoprotective protein that acts against various stresses, including heat stress. The aim of the present study was to identify gene networks involved in the enhancement of hyperthermia (HT) sensitivity by the knockdown (KD) of BAG3 in human oral squamous cell carcinoma (OSCC) cells. Although a marked elevation in the protein expression of BAG3 was detected in human the OSCC HSC-3 cells exposed to HT at 44˚C for 90 min, its expression was almost completely suppressed in the cells transfected with small interfering RNA against BAG3 (siBAG) under normal and HT conditions. The silencing of BAG3 also enhanced the cell death that was increased in the HSC-3 cells by exposure to HT. Global gene expression analysis revealed many genes that were differentially expressed by >2-fold in the cells exposed to HT and transfected with siBAG. Moreover, Ingenuity® pathways analysis demonstrated two unique gene networks, designated as Pro-cell death and Anti-cell death, which were obtained from upregulated genes and were mainly associated with the biological functions of induction and the prevention of cell death, respectively. Of note, the expression levels of genes in the Pro-cell death and Anti-cell death gene networks were significantly elevated and reduced in the HT + BAG3-KD group compared to those in the HT control group, respectively. These results provide further insight into the molecular mechanisms involved in the enhancement of HT sensitivity by the silencing of BAG3 in human OSCC cells.

Rat embryonic palatal shelves respond to TCDD in organ culture

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

Abbott, B.D.; Birnbaum, L.S.

1990-05-01

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), a highly toxic environmental contaminant, is teratogenic in mice, inducing cleft palate (CP) and hydronephrosis at doses which are not overtly maternally or embryo toxic. Palatal shelves of embryonic mice respond to TCDD, both in vivo and in organ culture, with altered differentiation of medial epithelial cells. By contrast, in the rat TCDD produces substantial maternal, embryonic, and fetal toxicity, including fetal lethality, with few malformations. In this study the possible effects of maternal toxicity on induction of cleft palate were eliminated by exposure of embryonic rat palatal shelves in organ culture. The shelves were examined for specificmore » TCDD-induced alterations in differentiation of the medial cells. On Gestation Day (GD) 14 or 15 palatal shelves from embryonic F344 rats were placed in organ culture for 2 to 3 days (IMEM:F12 medium, 5% FBS, 0.1% DMSO) containing 0, 1 x 10(-8), 1 x 10(-9), 1 x 10(-10), or 5 x 10(-11) M TCDD. The medial epithelial peridermal cells degenerated on shelves exposed to control media or 5 x 10(-11) M TCDD. Exposure to 10(-10), 10(-9), and 10(-8) M TCDD inhibited this degeneration in 20, 36, and 60% of the shelves, respectively, and was statistically significant at the two highest doses. A normally occurring decrease in (3H)TdR incorporation was inhibited in some GD 15 shelves cultured with 10(-10) and 10(-9) M TCDD. The medial cells of TCDD-exposed shelves continued to express high levels of immunohistochemically detected EGF receptors. The altered differentiation of rat medial epithelium is similar to that reported for TCDD-exposed mouse medial cells in vivo and in vitro. However, in order to obtain these responses, the cultured rat shelves require much higher concentrations of TCDD than the mouse shelves.« less

PM2.5-induced alterations of cell cycle associated gene expression in lung cancer cells and rat lung tissues.

PubMed

Zhao, Hui; Yang, Biao; Xu, Jia; Chen, Dong-Mei; Xiao, Chun-Ling

2017-06-01

The aim of the current study was to investigate the expression of cell cycle-associated genes induced by fine particulate matter (PM 2.5 ) in lung cancer cell line and tissues. The pulmonary lymph node metastasis cells (H292) were treated with PM 2.5 in vitro. Wistar rats were used to perform an in vivo study. Rats were randomly assigned to experiment and control groups and those in the experiment group were exposed to PM 2.5 once every 15 d, while those in the control group were exposed to normal saline. The cell cycle-associated genes expression was analyzed by real-time PCR. Trachea and lung tissues of rats were processed for scanning electron microscopic (SEM) examinations. Exposure of H292 cells to PM 2.5 dramatically increased the expressions of p53 and cyclin-dependent kinase 2 (CDK2) after 24h of exposure (p<0.01) and markedly increased the expressions of the cell division cycle 2 (Cdc2) and cyclin B after 48h of exposure (p<0.01), while those genes expressions were significantly reduced after 72h of exposure, at which time the expression of p21 was predominant (p<0.01). In vivo studies further demonstrated these results. The results of SEM suggested that both of the trachea and lung tissues were damaged and the degree of damage was time-dependent. In conclusion, PM 2.5 can induce significantly alterations of p53 and CDK2 in the early phase, Cdc2 and cyclin B in mid-term and p21 in long-term exposure. The degree of PM 2.5 -induced damage to the trachea and lung tissue was time-dependent. Copyright © 2017. Published by Elsevier B.V.

Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions

PubMed Central

Buonanno, Manuela; De Toledo, Sonia M.; Howell, Roger W.; Azzam, Edouard I.

2015-01-01

During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low ‘flux’ of the high atomic number and high energy (HZE) radiations relative to the higher ‘flux’ of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fibroblasts to a low mean absorbed dose of 20 cGy of 0.05 or 1-GeV protons (LET ∼ 1.25 or 0.2 keV/μm, respectively) protects the irradiated cells (P < 0.0001) against chromosomal damage induced by a subsequent exposure to a mean absorbed dose of 50 cGy from 1 GeV/u iron ions (LET ∼ 151 keV/μm). Surprisingly, unirradiated (i.e. bystander) cells with which the proton-irradiated cells were co-cultured were also significantly protected from the DNA-damaging effects of the challenge dose. The mitigating effect persisted for at least 24 h. These results highlight the interactions of biological effects due to direct cellular traversal by radiation with those due to bystander effects in cell populations exposed to mixed radiation fields. They show that protective adaptive responses can spread from cells targeted by low-LET space radiation to bystander cells in their vicinity. The findings are relevant to understanding the health hazards of space travel. PMID:25805407

Correlation of cytotoxic activity in lungs to recovery of normal and gamma-irradiated cotton rats from respiratory syncytial virus infection

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

Sun, C.S.; Wyde, P.R.; Knight, V.

1983-10-01

Cotton rats (Sigmodon hispidus) that were exposed to 300, 600, or 900 rads of gamma irradiation and inoculated intranasally 2 days later with respiratory syncytial virus (RSV) exhibited prolonged virus shedding and delayed humoral and cytotoxic immune responses compared with comparably inoculated nonirradiated control rats. In nonirradiated animals and in animals exposed to 300 and 600 rads, levels of virus declined and then disappeared from the lungs during the period in which cytotoxic activity was maximal in the lungs of these animals. In contrast, in the group of cotton rats exposed to 900 rads of irradiation, local cytotoxic activity remainedmore » low throughout the 11-day observation period, and virus was not eliminated from the lungs. Although virus-neutralizing antibodies in serum and lavage fluids from these animals may have been involved, correlation of antibody concentrations with virus clearance from lungs was not as evident. These data suggest that cytotoxic effector cells have a positive role in eliminating RSV from the lungs of unprimed cotton rats.« less

Tissue Factor-Factor VII Complex As a Key Regulator of Ovarian Cancer Phenotypes.

PubMed

Koizume, Shiro; Miyagi, Yohei

2015-01-01

Tissue factor (TF) is an integral membrane protein widely expressed in normal human cells. Blood coagulation factor VII (fVII) is a key enzyme in the extrinsic coagulation cascade that is predominantly secreted by hepatocytes and released into the bloodstream. The TF-fVII complex is aberrantly expressed on the surface of cancer cells, including ovarian cancer cells. This procoagulant complex can initiate intracellular signaling mechanisms, resulting in malignant phenotypes. Cancer tissues are chronically exposed to hypoxia. TF and fVII can be induced in response to hypoxia in ovarian cancer cells at the gene expression level, leading to the autonomous production of the TF-fVII complex. Here, we discuss the roles of the TF-fVII complex in the induction of malignant phenotypes in ovarian cancer cells. The hypoxic nature of ovarian cancer tissues and the roles of TF expression in endometriosis are discussed. Arguments will be extended to potential strategies to treat ovarian cancers based on our current knowledge of TF-fVII function.

The Effects of Ethanol on the Morphological and Biochemical Properties of Individual Human Red Blood Cells.

PubMed

Lee, Sang Yun; Park, Hyun Joo; Best-Popescu, Catherine; Jang, Seongsoo; Park, Yong Keun

2015-01-01

Here, we report the results of a study on the effects of ethanol exposure on human red blood cells (RBCs) using quantitative phase imaging techniques at the level of individual cells. Three-dimensional refractive index tomograms and dynamic membrane fluctuations of RBCs were measured using common-path diffraction optical tomography, from which morphological (volume, surface area, and sphericity); biochemical (hemoglobin (Hb) concentration and Hb content); and biomechanical (membrane fluctuation) parameters were retrieved at various concentrations of ethanol. RBCs exposed to the ethanol concentration of 0.1 and 0.3% v/v exhibited cell sphericities higher than those of normal cells. However, mean surface area and sphericity of RBCs in a lethal alcoholic condition (0.5% v/v) are not statistically different with those of healthy RBCs. Meanwhile, significant decreases of Hb content and concentration in RBC cytoplasm at the lethal condition were observed. Furthermore, dynamic fluctuation of RBC membranes increased significantly upon ethanol treatments, indicating ethanol-induced membrane fluidization.

Retrovirally mediated correction of bone marrow-derived mesenchymal stem cells from patients with mucopolysaccharidosis type I.

PubMed

Baxter, Melissa A; Wynn, Robert F; Deakin, Jonathan A; Bellantuono, Ilaria; Edington, Kirsten G; Cooper, Alan; Besley, Guy T N; Church, Heather J; Wraith, J Ed; Carr, Trevor F; Fairbairn, Leslie J

2002-03-01

We have investigated the utility of bone marrow-derived mesenchymal stem cells (MSCs) as targets for gene therapy of the autosomal recessive disorder mucopolysaccharidosis type IH (MPS-IH, Hurler syndrome). Cultures of MSCs were initially exposed to a green fluorescent protein-expressing retrovirus. Green fluorescent protein-positive cells maintained their proliferative and differentiation capacity. Next we used a vector encoding alpha-L-iduronidase (IDUA), the enzyme that is defective in MPS-IH. Following transduction, MPS-IH MSCs expressed high levels of IDUA and secreted supernormal levels of this enzyme into the extracellular medium. Exogenous IDUA expression led to a normalization of glycosaminoglycan storage in MPS-IH cells, as evidenced by a dramatic decrease in the amount of (35)SO(4) sequestered within the heparan sulfate and dermatan sulfate compartments of these cells. Finally, gene-modified MSCs were able to cross-correct the enzyme defect in untransduced MPS-IH fibroblasts via protein transfer.

The Effects of Low-Dose Bisphenol A and Bisphenol F on Neural Differentiation of a Fetal Brain-Derived Neural Progenitor Cell Line.

PubMed

Fujiwara, Yuki; Miyazaki, Wataru; Koibuchi, Noriyuki; Katoh, Takahiko

2018-01-01

Environmental chemicals are known to disrupt the endocrine system in humans and to have adverse effects on several organs including the developing brain. Recent studies indicate that exposure to environmental chemicals during gestation can interfere with neuronal differentiation, subsequently affecting normal brain development in newborns. Xenoestrogen, bisphenol A (BPA), which is widely used in plastic products, is one such chemical. Adverse effects of exposure to BPA during pre- and postnatal periods include the disruption of brain function. However, the effect of BPA on neural differentiation remains unclear. In this study, we explored the effects of BPA or bisphenol F (BPF), an alternative compound for BPA, on neural differentiation using ReNcell, a human fetus-derived neural progenitor cell line. Maintenance in growth factor-free medium initiated the differentiation of ReNcell to neuronal cells including neurons, astrocytes, and oligodendrocytes. We exposed the cells to BPA or BPF for 3 days from the period of initiation and performed real-time PCR for neural markers such as β III-tubulin and glial fibrillary acidic protein (GFAP), and Olig2. The β III-tubulin mRNA level decreased in response to BPA, but not BPF, exposure. We also observed that the number of β III-tubulin-positive cells in the BPA-exposed group was less than that of the control group. On the other hand, there were no changes in the MAP2 mRNA level. These results indicate that BPA disrupts neural differentiation in human-derived neural progenitor cells, potentially disrupting brain development.

Downregulation of Lysyl Oxidase Protects Retinal Endothelial Cells From High Glucose-Induced Apoptosis.

PubMed

Kim, Dongjoon; Mecham, Robert P; Trackman, Philip C; Roy, Sayon

2017-05-01

To investigate the effect of reducing high glucose (HG)-induced lysyl oxidase (LOX) overexpression and increased activity on retinal endothelial cell apoptosis. Rat retinal endothelial cells (RRECs) were grown in normal (N) or HG (30 mM glucose) medium for 7 days. In parallel, RRECs were grown in HG medium and transfected with LOX small interfering RNA (siRNA), scrambled siRNA as control, or exposed to β-aminopropionitrile (BAPN), a LOX inhibitor. LOX expression, AKT activation, and caspase-3 activity were determined by Western blot (WB) analysis and apoptosis by differential dye staining assay. Moreover, to determine whether diabetes-induced LOX overexpression alters AKT activation and promotes apoptosis, changes in LOX expression, AKT phosphorylation, caspase-3 activation, and Bax expression were assessed in retinas of streptozotocin (STZ)-induced diabetic mice and LOX heterozygous knockout (LOX+/-) mice. WB analysis indicated significant LOX overexpression and reduced AKT activation under HG condition in RRECs. Interestingly, when cells grown in HG were transfected with LOX siRNA or exposed to BAPN, the number of apoptotic cells was significantly decreased concomitant with increased AKT phosphorylation. Diabetic mouse retinas exhibited LOX overexpression, decreased AKT phosphorylation, and increased Bax and caspase-3 activation compared to values in nondiabetic mice. In LOX+/- mice, reduced LOX levels were observed with increased AKT activity, and reduced Bax and caspase-3 activity. Furthermore, decreased levels of LOX in the LOX+/- mice was protective against diabetes-induced apoptosis. Findings from this study indicate that preventing LOX overexpression may be protective against HG-induced apoptosis in retinal vascular cells associated with diabetic retinopathy.

Heat shock modulates the subcellular localization, stability, and activity of HIPK2

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

Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam, E-mail: sganesh@iitk.ac.in

2016-04-15

The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress – such as hypoxia, oxidative stress, or UV damage – is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 andmore » the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors.« less

Effect of mitomycin on normal dermal fibroblast and HaCat cell: an in vitro study

PubMed Central

Wang, Yao-wen; Ren, Ji-hao; Xia, Kun; Wang, Shu-hui; Yin, Tuan-fang; Xie, Ding-hua; Li, Li-hua

2012-01-01

Objective: To evaluate the effects of mitomycin on the growth of human dermal fibroblast and immortalized human keratinocyte line (HaCat cell), particularly the effect of mitomycin on intracellular messenger RNA (mRNA) synthesis of collagen and growth factors of fibroblast. Methods: The normal dermal fibroblast and HaCat cell were cultured in vitro. Cell cultures were exposed to 0.4 and 0.04 mg/ml of mitomycin solution, and serum-free culture medium was used as control. The cellular morphology change, growth characteristics, cell proliferation, and apoptosis were observed at different intervals. For the fibroblasts, the mRNA expression changes of transforming growth factor (TGF)-β1, basic fibroblast growth factor (bFGF), procollagen I, and III were detected by reverse transcription polymerase chain reaction (RT-PCR). Results: The cultured normal human skin fibroblast and HaCat cell grew exponentially. A 5-min exposure to mitomycin at either 0.4 or 0.04 mg/ml caused marked dose-dependent cell proliferation inhibition on both fibroblasts and HaCat cells. Cell morphology changed, cell density decreased, and the growth curves were without an exponential phase. The fibroblast proliferated on the 5th day after the 5-min exposure of mitomycin at 0.04 mg/ml. Meanwhile, 5-min application of mitomycin at either 0.04 or 0.4 mg/ml induced fibroblast apoptosis but not necrosis. The apoptosis rate of the fibroblast increased with a higher concentration of mytomycin (p<0.05). A 5-min exposure to mitomycin at 0.4 mg/ml resulted in a marked decrease in the mRNA production of TGF-β1, procollagen I and III, and a marked increase in the mRNA production of bFGF. Conclusions: Mitomycin can inhibit fibroblast proliferation, induce fibroblast apoptosis, and regulate intracellular protein expression on mRNA levels. In additon, mitomycin can inhibit HaCat cell proliferation, so epithelial cell needs more protecting to avoid mitomycin’s side effect when it is applied clinically. PMID:23225855

Optical Analysis of Transparent Polymeric Material Exposed to Simulated Space Environment

NASA Technical Reports Server (NTRS)

Edwards, David L.; Finckenor, Miria M.

1999-01-01

Transparent polymeric materials are being designed and utilized as solar concentrating lenses for spacecraft power and propulsion systems. These polymeric lenses concentrate solar energy onto energy conversion devices such as solar cells and thermal energy systems. The conversion efficiency is directly related to the transmissivity of the polymeric lens. The Environmental Effects Group of the Marshall Space Flight Center's Materials, Processes, and Manufacturing Department exposed a variety of materials to a simulated space environment and evaluated them for an, change in optical transmission. These materials include Lexan(TM), polyethylene terephthalate (PET). several formulations of Tefzel(TM). and Teflon(TM), and silicone DC 93-500. Samples were exposed to a minimum of 1000 Equivalent Sun Hours (ESH) of near-UV radiation (250 - 400 nm wavelength). Data will be presented on materials exposed to charged particle radiation equivalent to a five-year dose in geosynchronous orbit. These exposures were performed in MSFC's Combined Environmental Effects Test Chamber, a unique facility with the capability to expose materials simultaneously or sequentially to protons, low-energy electrons, high-energy electrons, near UV radiation and vacuum UV radiation.Prolonged exposure to the space environment will decrease the polymer film's transmission and thus reduce the conversion efficiency. A method was developed to normalize the transmission loss and thus rank the materials according to their tolerance to space environmental exposure. Spectral results and the material ranking according to transmission loss are presented.

Electromagnetic fields used clinically to improve bone healing also impact lymphocyte proliferation in vitro.

PubMed

Johnson, M T; Vanscoy-Cornett, A; Vesper, D N; Swez, J A; Chamberlain, J K; Seaward, M B; Nindl, G

2001-01-01

An important aspect of medical device development is the need to understand how a device produces a specific biological effect. The focus can then be on optimizing that effect by device modification and repeated testing. Several reports from this lab have targeted programmed cell death, or apoptosis, as a cellular pathway that is induced by exposure of transformed leukemic T-cells in culture to specific frequency and intensity electromagnetic fields (EMFs). An EMF delivery device capable of selectively inducing T-cell apoptosis in human tissues could be used to enhance healing by limiting the production of molecules that promote inflammatory disorders such as psoriasis and tendonitis. In the present study, we examined the normal T-cell response to EMF exposure in vitro. In the peripheral blood, 70-80% of the lymphocytes are T-cells, and thus is a rich source of normal cells that match the transformed T-cells used in other experiments (Jurkat cells). We isolated lymphocytes from the peripheral blood of humans and rats, cultured them in nutritive medium and exposed them to either a complex 1.8 mT pulsed EMF (Electrobiology, Inc.), a 0.1 mT, 60 Hz power frequency EMF or a 0.2 mT, 100 Hz sinusoidal EMF. Control lymphocytes were cultured similarly, without field exposure. Lymphocytes were then treated with T-cell mitogens and evaluated for proliferative capacity after an additional 72 hours culture. Results indicate that T-cell proliferation is modulated by in vitro exposure to defined EMFs. The potential use of an EMF delivery device capable of selectively inducing such T-cell effects is discussed.

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

Chan, R.K.; Otte, C.A.

Saccharomyces cerevisiae MATa cells carrying mutations in either sst1 or sst2 are supersensitive to the G1 arrest induced by ..cap alpha.. factor pheromone. When sst1 mutants were mixed with normal SST/sup +/ cells, the entire population recovered together from ..cap alpha.. factor arrest, suggesting that SST/sup +/ cells helped sst1 mutants to recover. Complementation tests and linkage analysis showed that sst1 and bar1, a mutation which eliminates the ability of MATa cells to act as a ''barrier'' to the diffusion of ..cap alpha.. factor, were lesions in the same genes. These findings suggest that sst1 mutants are defective in recoverymore » from ..cap alpha.. factor arrest because they are unable to degrade the pheromone. In contrast, recovery of sst2 mutants was not potentiated by the presence of SST/sup +/ cells in mixing experiments. When either normal MATa cells or mutant cells carrying defects in sst1 or sst2 were exposed to ..cap alpha.. factor for 1 h and then washed free of the pheromone, the sst2 cells subsequently remained arrested in the absence of ..cap alpha.. factor for a much longer time than SST/sup +/ or sst1 cells. These observations suggest that the defect in sst2 mutants is intrinsic to the cell and is involved in the mechanism of ..cap alpha.. factor action at some step after the initial interaction of the pheromone with the cell. The presence of an sst2 mutation appears to cause a growth debility, since repeated serial subculture of haploid sst2-1 strains led to the accumulation of faster-growing revertants that were pheromone resistant and were mating defective (''sterile'').« less

Protection by extra virgin olive oil against oxidative stress in vitro and in vivo. Chemical and biological studies on the health benefits due to a major component of the Mediterranean diet.

PubMed

Rossi, Miriam; Caruso, Francesco; Kwok, Lorraine; Lee, Grace; Caruso, Alessio; Gionfra, Fabio; Candelotti, Elena; Belli, Stuart L; Molasky, Nora; Raley-Susman, Kathleen M; Leone, Stefano; Filipský, Tomáš; Tofani, Daniela; Pedersen, Jens; Incerpi, Sandra

2017-01-01

We report the results of in vivo studies in Caenorhabditis elegans nematodes in which addition of extra virgin olive oil (EVOO) to their diet significantly increased their life span with respect to the control group. Furthermore, when nematodes were exposed to the pesticide paraquat, they started to die after two days, but after the addition of EVOO to their diet, both survival percentage and lifespans of paraquat-exposed nematodes increased. Since paraquat is associated with superoxide radical production, a test for scavenging this radical was performed using cyclovoltammetry and the EVOO efficiently scavenged the superoxide. Thus, a linear correlation (y = -0.0838x +19.73, regression factor = 0.99348) was observed for superoxide presence (y) in the voltaic cell as a function of aliquot (x) additions of EVOO, 10 μL each. The originally generated supoeroxide was approximately halved after 10 aliquots (100 μL total). The superoxide scavenging ability was analyzed, theoretically, using Density Functional Theory for tyrosol and hydroxytyrosol, two components of EVOO and was also confirmed experimentally for the galvinoxyl radical, using Electron Paramagnetic Resonance (EPR) spectroscopy. The galvinoxyl signal disappeared after adding 1 μL of EVOO to the EPR cell in 10 minutes. In addition, EVOO significantly decreased the proliferation of human leukemic THP-1 cells, while it kept the proliferation at about normal levels in rat L6 myoblasts, a non-tumoral skeletal muscle cell line. The protection due to EVOO was also assessed in L6 cells and THP-1 exposed to the radical generator cumene hydroperoxide, in which cell viability was reduced. Also in this case the oxidative stress was ameliorated by EVOO, in line with results obtained with tetrazolium dye reduction assays, cell cycle analysis and reactive oxygen species measurements. We ascribe these beneficial effects to EVOO antioxidant properties and our results are in agreement with a clear health benefit of EVOO use in the Mediterranean diet.

Protection by extra virgin olive oil against oxidative stress in vitro and in vivo. Chemical and biological studies on the health benefits due to a major component of the Mediterranean diet

PubMed Central

Rossi, Miriam; Kwok, Lorraine; Lee, Grace; Caruso, Alessio; Gionfra, Fabio; Candelotti, Elena; Belli, Stuart L.; Molasky, Nora; Raley-Susman, Kathleen M.; Leone, Stefano; Filipský, Tomáš; Tofani, Daniela; Pedersen, Jens; Incerpi, Sandra

2017-01-01

We report the results of in vivo studies in Caenorhabditis elegans nematodes in which addition of extra virgin olive oil (EVOO) to their diet significantly increased their life span with respect to the control group. Furthermore, when nematodes were exposed to the pesticide paraquat, they started to die after two days, but after the addition of EVOO to their diet, both survival percentage and lifespans of paraquat-exposed nematodes increased. Since paraquat is associated with superoxide radical production, a test for scavenging this radical was performed using cyclovoltammetry and the EVOO efficiently scavenged the superoxide. Thus, a linear correlation (y = -0.0838x +19.73, regression factor = 0.99348) was observed for superoxide presence (y) in the voltaic cell as a function of aliquot (x) additions of EVOO, 10 μL each. The originally generated supoeroxide was approximately halved after 10 aliquots (100 μL total). The superoxide scavenging ability was analyzed, theoretically, using Density Functional Theory for tyrosol and hydroxytyrosol, two components of EVOO and was also confirmed experimentally for the galvinoxyl radical, using Electron Paramagnetic Resonance (EPR) spectroscopy. The galvinoxyl signal disappeared after adding 1 μL of EVOO to the EPR cell in 10 minutes. In addition, EVOO significantly decreased the proliferation of human leukemic THP-1 cells, while it kept the proliferation at about normal levels in rat L6 myoblasts, a non-tumoral skeletal muscle cell line. The protection due to EVOO was also assessed in L6 cells and THP-1 exposed to the radical generator cumene hydroperoxide, in which cell viability was reduced. Also in this case the oxidative stress was ameliorated by EVOO, in line with results obtained with tetrazolium dye reduction assays, cell cycle analysis and reactive oxygen species measurements. We ascribe these beneficial effects to EVOO antioxidant properties and our results are in agreement with a clear health benefit of EVOO use in the Mediterranean diet. PMID:29283995

Protection against ultraviolet A-induced oxidative damage in normal human epidermal keratinocytes under post-menopausal conditions by an ultraviolet A-activated caged-iron chelator: a pilot study.

PubMed

Pelle, Edward; Jian, Jinlong; Declercq, Lieve; Dong, Kelly; Yang, Qing; Pourzand, Charareh; Maes, Daniel; Pernodet, Nadine; Yarosh, Daniel B; Huang, Xi

2011-10-01

Human skin is constantly exposed to ultraviolet A (UVA), which can generate reactive oxygen species and cause iron release from ferritin, leading to oxidative damage in biomolecules. This is particularly true in post-menopausal skin due to an increase in iron as a result of menopause. As iron is generally released through desquamation, the skin becomes a main portal for the release of excess iron in this age group. In the present study, we examined a strategy for controlling UVA- and iron-induced oxidative stress in skin using a keratinocyte post-menopausal cellular model system. Keratinocytes that had been cultured under normal or high-iron, low-estrogen conditions were treated with (2-nitrophenyl) ethyl pyridoxal isonicotinoyl hydrazone (2-PNE-PIH). 2-PNE-PIH is a caged-iron chelator that does not normally bind iron but can be activated by UVA radiation to bind iron. Following incubation with 2-PNE-PIH, the cells were exposed to 5 J/cm² UVA and then measured for changes in lipid peroxidation and ferritin levels. 2-PNE-PIH protected keratinocytes against UVA-induced lipid peroxidation and ferritin depletion. Further, 2-PNE-PIH was neither cytotoxic nor did it alter iron metabolism. 2-PNE-PIH may be a useful deterrent against UVA-induced oxidative stress in post-menopausal women. © 2011 John Wiley & Sons A/S.

Quantitative analysis of gold nanoparticles in single cells by laser ablation inductively coupled plasma-mass spectrometry.

PubMed

Wang, Meng; Zheng, Ling-Na; Wang, Bing; Chen, Han-Qing; Zhao, Yu-Liang; Chai, Zhi-Fang; Reid, Helen J; Sharp, Barry L; Feng, Wei-Yue

2014-10-21

Single cell analysis has become an important field of research in recent years reflecting the heterogeneity of cellular responses in biological systems. Here, we demonstrate a new method, based on laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), which can quantify in situ gold nanoparticles (Au NPs) in single cells. Dried residues of picoliter droplets ejected by a commercial inkjet printer were used to simulate matrix-matched calibration standards. The gold mass in single cells exposed to 100 nM NIST Au NPs (Reference material 8012, 30 nm) for 4 h showed a log-normal distribution, ranging from 1.7 to 72 fg Au per cell, which approximately corresponds to 9 to 370 Au NPs per cell. The average result from 70 single cells (15 ± 13 fg Au per cell) was in good agreement with the result from an aqua regia digest solution of 1.2 × 10(6) cells (18 ± 1 fg Au per cell). The limit of quantification was 1.7 fg Au. This paper demonstrates the great potential of LA-ICPMS for single cell analysis and the beneficial study of biological responses to metal drugs or NPs at the single cell level.

Morphometrical and Morphological Alterations of Human Leukocytes Exposed to 1.8 GHz Electromagnetic Radiations: In Vitro Protective Effects Induced by Polyphenols.

PubMed

Biagi, Pier Francesco; Boffola, Sara; Stefanelli, Riccardo; Schiavulli, Luigi; Ligonzo, Teresa; Casamassima, Giuseppe; Pappagallo, Maria Teresa; Kawaguchi, Kiichiro; Takimoto, Hiroaki; Kumazawa, Yoshio; Fontana, Sergio; Laforgia, Flavia; Russo, Matteo Antonio; Magrone, Thea; Jirillo, Emilio

2016-01-01

Our recent findings have demonstrated that electromagnetic radiations (EMR) (1.8 GHz radiofrequency) are able to in vitro induce morphometrical and morphological modifications of human leukocytes from normal donors. In view of the evidence that polyphenols exert many beneficial effects on plants, animals and humans, leukocytes from human peripheral blood were pre-treated for 1 h with two polyphenol preparations from red grape before EMR exposure (1.8 GHz). Our data will show that polyphenol pre-treatment reverts to normality the morphology of irradiated leukocytes in comparison to irradiated cells only. Conversely, leukocyte morphometry seems to be not affected by this treatment. Here, we demonstrate that polyphenols are also able to normalize leukocyte morphology per se altered before as well as after irradiation. Finally, a working hypothesis aimed at clarifying the protective mechanisms exerted by polyphenols on irradiated leukocytes will be illustrated. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Cadmium induces histopathological injuries and ultrastructural changes in the liver of freshwater turtle (Chinemys reevesii).

PubMed

Huo, Junfeng; Dong, Aiguo; Wang, Yonghui; Lee, Shaochin; Ma, Cungen; Wang, Lan

2017-11-01

The study investigated the histopathological and ultrastructural lesions of liver of freshwater turtle Chinemys reevesii exposed to Cadmium (Cd). The animals were exposed to 0 mg kg -1 (0.85% normal saline (NS)), 7.5 mg kg -1 , 15 mg kg -1 , 30 mg kg -1 Cd chloride separately by intraperitoneal injection. Liver samples were collected for examination of lesions under light and electronic microscopes. Results showed that liver tissues from Cd -treated animals presented various degrees of histopathological lesions. Liver cells showed swollen, degeneration and necrosis with dose-dependent manner. Under electronic microscope, nucleus, mitochondria and rough endoplasmic reticulum presented various degrees of lesions with dose-dependent manner. In conclusion, Cd has significant toxicity on liver tissue of the freshwater turtle, which occurs in a dose-dependent manner. Copyright © 2017 Elsevier Ltd. All rights reserved.

The controlled-environment chamber: a new mouse model of dry eye.

PubMed

Barabino, Stefano; Shen, Linling; Chen, Lu; Rashid, Saadia; Rolando, Maurizio; Dana, M Reza

2005-08-01

To develop a controlled-environment chamber (CEC) for mice and verify the effects of a low-humidity setting on ocular surface signs in normal mice. Eight- to 12-week-old BALB/c mice were used in a controlled-environment chamber (CEC) where relative humidity (RH), temperature (T), and airflow (AF) are regulated and monitored. Mice were placed into the CEC and exposed to specific environmentally controlled conditions (RH = 18.5% +/- 5.1%, AF = 15 L/min, T = 21-23 degrees C) for 3, 7, 14, and 28 days. Control mice were kept in a normal environment (RH = 50%-80%, no AF, T = 21-23 degrees C) for the same duration. Aqueous tear production by means of the cotton thread test, corneal fluorescein staining (score, 0-15), and goblet cell density in the superior and inferior conjunctiva were measured by a masked observer. No statistically significant differences between the groups were found at baseline. Decreased tear secretion and increased corneal fluorescein staining were significantly present on day 3, 7, 14, and 28 in animals kept in the CEC. Goblet cell density was significantly decreased in the superior conjunctiva on day 7, and on day 3, 7, and 14 in the inferior conjunctiva in the CEC-kept mice compared with control animals. This study indicates that exposure of normal mice to a low-humidity environment in a CEC can lead to significant alterations in tear secretion, goblet cell density, and acquisition of dry eye-related ocular surface signs.

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.

Human endothelial cell responses to cardiovascular inspired pulsatile shear stress

NASA Astrophysics Data System (ADS)

Watson, Matthew; Baugh, Lauren; Black, Lauren, III; Kemmerling, Erica

2016-11-01

It is well established that hemodynamic shear stress regulates blood vessel structure and the development of vascular pathology. This process can be studied via in vitro models of endothelial cell responses to pulsatile shear stress. In this study, a macro-scale cone and plate viscometer was designed to mimic various shear stress waveforms found in the body and apply these stresses to human endothelial cells. The device was actuated by a PID-controlled DC gear-motor. Cells were exposed to 24 hours of pulsatile shear and then imaged and stained to track their morphology and secretions. These measurements were compared with control groups of cells exposed to constant shear and no shear. The results showed that flow pulsatility influenced levels of secreted proteins such as VE-cadherin and neuroregulin IHC. Cell morphology was also influenced by flow pulsatility; in general cells exposed to pulsatile shear stress developed a higher aspect ratio than cells exposed to no flow but a lower aspect ratio than cells exposed to steady flow.

Controlled release of 18-β-glycyrrhetic acid by nanodelivery systems increases cytotoxicity on oral carcinoma cell line

NASA Astrophysics Data System (ADS)

Cacciotti, Ilaria; Chronopoulou, Laura; Palocci, Cleofe; Amalfitano, Adriana; Cantiani, Monica; Cordaro, Massimo; Lajolo, Carlo; Callà, Cinzia; Boninsegna, Alma; Lucchetti, Donatella; Gallenzi, Patrizia; Sgambato, Alessandro; Nocca, Giuseppina; Arcovito, Alessandro

2018-07-01

The topical treatment for oral mucosal diseases is often based on products optimized for dermatologic applications; consequently, a lower therapeutic effect may be present. 18-β-glycyrrhetic acid (GA) is extracted from Glycirrhiza glabra. The first aim of this study was to test the cytotoxicity of GA on PE/CA-PJ15 cells. The second aim was to propose and test two different delivery systems, i.e. nanoparticles and fibers, to guarantee a controlled release of GA in vitro. We used chitosan and poly(lactic-co-glycolic) acid based nanoparticles and polylactic acid fibers. We tested both delivery systems in vitro on PE/CA-PJ15 cells and on normal human gingival fibroblasts (HGFs). The morphology of GA-loaded nanoparticles (GA-NPs) and fibers (GA-FBs) was investigated by electron microscopy and dynamic light scattering; GA release kinetics was studied spectrophotometrically. MTT test was used to assess GA cytotoxicity on both cancer and normal cells. Cells were exposed to different concentrations of GA (20–500 μmol l‑1) administered as free GA (GA-f), and to GA-NPs or GA-FBs. ROS production was evaluated using dichlorodihydrofluorescein as a fluorescent probe. Regarding the cytotoxic effect of GA on PE/CA-PJ15 cells, the lowest TC50 value was 200 μmol l‑1 when GA was added as GA-NPs. No cytotoxic effects were observed when GA was administered to HGFs. N-acetyl Cysteine reduced mortality induced by GA-f in PE/CA-PJ15 cells. The specific effect of GA on PE/CA-PJ15 cells is mainly due to the different sensitivity of cancer cells to ROS over-production; GA-NPs and GA-FBs formulations increase, in vitro, this toxic effect on oral cancer cells.

Recognition and Blocking of Innate Immunity Cells by Candida albicans Chitin ▿ †

PubMed Central

Mora-Montes, Héctor M.; Netea, Mihai G.; Ferwerda, Gerben; Lenardon, Megan D.; Brown, Gordon D.; Mistry, Anita R.; Kullberg, Bart Jan; O'Callaghan, Chris A.; Sheth, Chirag C.; Odds, Frank C.; Brown, Alistair J. P.; Munro, Carol A.; Gow, Neil A. R.

2011-01-01

Chitin is a skeletal cell wall polysaccharide of the inner cell wall of fungal pathogens. As yet, little about its role during fungus-host immune cell interactions is known. We show here that ultrapurified chitin from Candida albicans cell walls did not stimulate cytokine production directly but blocked the recognition of C. albicans by human peripheral blood mononuclear cells (PBMCs) and murine macrophages, leading to significant reductions in cytokine production. Chitin did not affect the induction of cytokines stimulated by bacterial cells or lipopolysaccharide (LPS), indicating that blocking was not due to steric masking of specific receptors. Toll-like receptor 2 (TLR2), TLR4, and Mincle (the macrophage-inducible C-type lectin) were not required for interactions with chitin. Dectin-1 was required for immune blocking but did not bind chitin directly. Cytokine stimulation was significantly reduced upon stimulation of PBMCs with heat-killed chitin-deficient C. albicans cells but not with live cells. Therefore, chitin is normally not exposed to cells of the innate immune system but is capable of influencing immune recognition by blocking dectin-1-mediated engagement with fungal cell walls. PMID:21357722

An untargeted multi-technique metabolomics approach to studying intracellular metabolites of HepG2 cells exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin.

PubMed

Ruiz-Aracama, Ainhoa; Peijnenburg, Ad; Kleinjans, Jos; Jennen, Danyel; van Delft, Joost; Hellfrisch, Caroline; Lommen, Arjen

2011-05-20

In vitro cell systems together with omics methods represent promising alternatives to conventional animal models for toxicity testing. Transcriptomic and proteomic approaches have been widely applied in vitro but relatively few studies have used metabolomics. Therefore, the goal of the present study was to develop an untargeted methodology for performing reproducible metabolomics on in vitro systems. The human liver cell line HepG2, and the well-known hepatotoxic and non-genotoxic carcinogen 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), were used as the in vitro model system and model toxicant, respectively. The study focused on the analysis of intracellular metabolites using NMR, LC-MS and GC-MS, with emphasis on the reproducibility and repeatability of the data. State of the art pre-processing and alignment tools and multivariate statistics were used to detect significantly altered levels of metabolites after exposing HepG2 cells to TCDD. Several metabolites identified using databases, literature and LC-nanomate-Orbitrap analysis were affected by the treatment. The observed changes in metabolite levels are discussed in relation to the reported effects of TCDD. Untargeted profiling of the polar and apolar metabolites of in vitro cultured HepG2 cells is a valid approach to studying the effects of TCDD on the cell metabolome. The approach described in this research demonstrates that highly reproducible experiments and correct normalization of the datasets are essential for obtaining reliable results. The effects of TCDD on HepG2 cells reported herein are in agreement with previous studies and serve to validate the procedures used in the present work.

Temozolomide does not influence the transcription or activity of matrix metalloproteinases 9 and 2 in glioma cell lines.

PubMed

Suzuki, Yuta; Fujioka, Kouki; Ikeda, Keiichi; Murayama, Yuichi; Manome, Yoshinobu

2017-07-01

Glioblastoma multiforme (GBM) is a treatment-resistant malignancy with poor prognosis. Temozolomide (TMZ) is widely used as a first-line drug for GBM. Although this improves patient prognosis, it does not completely eradicate the tumour. Even after total surgical resection, GBM can exhibit uncontrollable invasiveness at the tumour margins owing to activation of matrix metalloproteinases (MMPs) such as MMP-2 and -9; these degrade collagen IV in the basement membrane, which normally prevents cancer invasion. TMZ induces DNA damage and activates transcription factors including c-jun, c-fos, nuclear factor-κβ, and early growth response protein-1, which have putative binding sites on the MMP-9 promoter. TMZ may therefore enhance tumour invasion by stimulating MMP-9 transcription and enzymatic activity. To test this hypothesis, we investigated MMP-2 and -9 mRNA transcription and activity in GBM cell lines treated with TMZ. Human A172 GBM cells were exposed to TMZ (25% and 50% inhibitory concentrations) for 24 or 48h; cell cycle distribution and mRNA levels of MMP-2 and -9 were evaluated using flow cytometry and semi-quantitative reverse transcription PCR, respectively. MMP-2 and -9 enzymatic activities were assessed using gelatin zymography in human A172 and U373 MG GBM cells exposed to TMZ under the same conditions. TMZ altered A172 cell cycle distribution, but not MMP-2 or -9 mRNA levels. TMZ did not affect MMP-2 or -9 enzymatic activities in A172 or U373 MG cells. These findings indicated that TMZ is therefore unlikely to promote GBM invasiveness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessing the photoaging process at sun exposed and non-exposed skin using fluorescence lifetime spectroscopy

NASA Astrophysics Data System (ADS)

Saito Nogueira, Marcelo; Kurachi, Cristina

2016-03-01

Photoaging is the skin premature aging due to exposure to ultraviolet light, which damage the collagen, elastin and can induce alterations on the skin cells DNA, and, then, it may evolve to precancerous lesions, which are widely investigated by fluorescence spectroscopy and lifetime. The fluorescence spectra and fluorescence lifetime analysis has been presented as a technique of great potential for biological tissue characterization at optical diagnostics. The main targeted fluorophores are NADH (nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide), which have free and bound states, each one with different average lifetimes. The average lifetimes for free and bound NADH and FAD change according to tissue metabolic alterations and may contribute to a non-invasive clinical investigation of injuries such as skin lesions. These lesions and the possible areas where they may develop can be interrogated using fluorescence lifetime spectroscopy taking into account the variability of skin phototypes and the changes related to melanin, collagen and elastin, endogenous fluorophores which have emissions that spectrally overlap to the NADH and FAD emission. The objective of this study is to assess the variation on fluorescence lifetimes of normal skin at sun exposed and non-exposed areas and associate this variation to the photoaging process.

Upregulated Expression of Transient Receptor Potential Cation Channel Subfamily V Receptors in Mucosae of Patients with Oral Squamous Cell Carcinoma and Patients with a History of Alcohol Consumption or Smoking.

PubMed

Sakakibara, Akiko; Sakakibara, Shunsuke; Kusumoto, Junya; Takeda, Daisuke; Hasegawa, Takumi; Akashi, Masaya; Minamikawa, Tsutomu; Hashikawa, Kazunobu; Terashi, Hiroto; Komori, Takahide

2017-01-01

Transient receptor potential cation channel (subfamily V, members 1-4) (TRPV1-4) are expressed in skin and neurons and activated by external stimuli in normal mucosae of all oral cavity sites. The oral cavity is exposed to various stimuli, including temperature, mechanical stimuli, chemical substances, and changes in pH, and, notably, the risk factors for oncogenic transformation in oral squamous epithelium are the same as the external stimuli received by TRPV1-4 receptors. Hence, we examined the relationship between oral squamous cell carcinoma (SCC) and TRPV1-4 expression. Oral SCC patients (n = 37) who underwent surgical resection were included in this study. We investigated the expression of TRPV1-4 by immunohistochemical staining and quantification of TRPV1-4 mRNA in human oral mucosa. In addition, we compared the TRPV1-4 levels in mucosa from patients with SCC to those in normal oral mucosa. The receptors were expressed in oral mucosa at all sites (tongue, buccal mucosa, gingiva, and oral floor) and the expression was stronger in epithelia from patients with SCC than in normal epithelia. Furthermore, alcohol consumption and tobacco use were strongly associated with the occurrence of oral cancer and were found to have a remarkable influence on TRPV1-4 receptor expression in normal oral mucosa. In particular, patients with a history of alcohol consumption demonstrated significantly higher expression levels. Various external stimuli may influence the behavior of cancer cells. Overexpression of TRPV1-4 is likely to be a factor in enhanced sensitivity to external stimuli. These findings could contribute to the establishment of novel strategies for cancer therapy or prevention.

Ultrastructure of cells of Ulmus americana cultured in vitro and exposed to the culture filtrate of Ceratocystis ulmi

Treesearch

Paula M. Pijut; R. Daniel Lineberger; Subhash C. Domir; Jann M. Ichida; Charles R. Krause

1990-01-01

Calli of American elm susceptible and resistant to Dutch elm disease were exposed to a culture filtrate of a pathogenic isolate of Ceratocystis ulmi. Cells from untreated tissue exhibited typical internal composition associated with healthy, actively growing cells. All cells exposed to culture filtrate showed appreciable ultrastructural changes....

Protection against oxidative DNA damage and stress in human prostate by glutathione S-transferase P1

PubMed Central

Kanwal, Rajnee; Pandey, Mitali; Bhaskaran, Natarajan; MacLennan, Gregory T; Fu, Pingfu; Ponsky, Lee E; Gupta, Sanjay

2014-01-01

The pi-class glutathione S-transferase (GSTP1) actively protect cells from carcinogens and electrophilic compounds. Loss of GSTP1 expression via promoter hypermethylation is the most common epigenetic alteration observed in human prostate cancer. Silencing of GSTP1 can increase generation of reactive oxygen species (ROS) and DNA damage in cells. In this study we investigated whether loss of GSTP1 contributes to increased DNA damage that may predispose men to a higher risk of prostate cancer. We found significantly elevated (103%; P<0.0001) levels of 8-oxo-2′-deoxogunosine (8-OHdG), an oxidative DNA damage marker, in adenocarcinomas, compared to benign counterparts, which positively correlated (r=0.2) with loss of GSTP1 activity (34%; P<0.0001). Silencing of GSTP1 using siRNA approach in normal human prostate epithelial RWPE1 cells caused increased intracellular production of ROS and higher susceptibility of cells to H2O2-mediated oxidative stress. Additionally, human prostate carcinoma LNCaP cells, which contain a silenced GSTP1 gene, were genetically modified to constitutively express high levels of GSTP1. Induction of GSTP1 activity lowered endogenous ROS levels in LNCaP-pLPCX-GSTP1 cells, and when exposed to H2O2, these cells exhibited significantly reduced production of ROS and 8-OHdG levels, compared to vector control LNCaP-pLPCX cells. Furthermore, exposure of LNCaP cells to green tea polyphenols caused re-expression of GSTP1, which protected the cells from H2O2-mediated DNA damage through decreased ROS production compared to non-exposed cells. These results suggest that loss of GSTP1 expression in human prostate cells, a process that increases their susceptibility to oxidative stress-induced DNA damage, may be an important target for primary prevention of prostate cancer. PMID:22833520

Functional convergence of Akt protein with VEGFR-1 in human endothelial progenitor cells exposed to sera from patient with type 2 diabetes mellitus.

PubMed

Hassanpour, Mehdi; Rezabakhsh, Aysa; Rahbarghazi, Reza; Nourazarian, Alireza; Nouri, Mohammad; Avci, Çığır Biray; Ghaderi, Shahrooz; Alidadyani, Neda; Bagca, Bakiye Goker; Bagheri, Hesam Saghaei

2017-11-01

Diabetes mellitus type 2 predisposes patients to various microvascular complications. In the current experiment, the potent role of diabetes mellitus was investigated on the content of VEGFR-1, -2, Tie-1 and -2, and Akt in human endothelial progenitor cells. The gene expression profile of mTOR and Hedgehog signaling pathways were measured by PCR array. The possible crosstalk between RTKs, mTOR and Hedgehog signaling was also studied by bioinformatic analysis. Endothelial progenitor cells were incubated with serum from normal and diabetic for 7days. Compared to non-treated cells, diabetic serum-induced cell apoptosis (~2-fold) and prohibited cell migration toward bFGF (p<0.001). ELISA analysis showed that diabetes exposed cells had increased abundance of Tie-1, -2 and VEGFR-2 and reduced amount of VEGFR-1 (p<0.0001) in diabetic cells. Western blotting showed a marked reduction in the protein level of Akt after cells exposure to serum from diabetic subjects (p<0.0001). PCR array revealed a significant stimulation of both mTOR and Hedgehog signaling pathways in diabetic cells (p<0.05). According to data from bioinformatic datasets, we showed VEGFR-1, -2 and Tie-2, but not Tie-1, are master regulators of angiogenesis. There is a crosstalk between RTKs and mTOR signaling by involving P62, GABARAPL1, and HTT genes. It seems that physical interaction and co-expression of Akt decreased the level of VEGFR-1 in diabetic cells. Regarding data from the present experiment, diabetic serum contributed to uncontrolled induction of both mTOR and Hedgehog signaling in endothelial progenitor cells. Diabetes mellitus induces mTOR pathway by involving receptor tyrosine kinases while Hedgehog stimulation is independent of these receptors. Copyright © 2017 Elsevier Inc. All rights reserved.

Aqueous extract from Vitis vinifera tendrils is able to enrich keratinocyte antioxidant defences.

PubMed

Fraternale, Daniele; De Bellis, Roberta; Calcabrini, Cinzia; Potenza, Lucia; Cucchiarini, Luigi; Mancini, Umberto; Dachà, Marina; Ricci, Donata

2011-09-01

An aqueous extract of V. vinifera L. tendrils was evaluated for its ability to enrich the antioxidant capacity of cultured cells. The long-time antioxidant capability of the extract was measured by in vitro chemical methods, and its influence on reduced glutathione levels and plasma membrane oxido reductase activity was determined in cultured human keratinocytes (NCTC 2544). Keratinocytes are cells normally exposed to oxidative stress, and for this reason adequately equipped with antioxidant defences. However, it has long been suggested that exogenous antioxidants may play an important role in minimizing the adverse effects of oxidative stress on skin.We demonstrated that V. vinifera tendril aqueous extract was able to increase, in a time- and dose-dependent manner, the reduced glutathione concentration and activity of trans plasma membrane oxido reductase as an indirect evaluation of the intracellular redox status of the cells demonstrating a relevant antioxidant activity of this phytocomplex.

The effects of hypobaric hypoxia (50.6 kPa) on blood components in guinea-pigs.

PubMed

Osada, H

1991-06-01

One hundred and five male (Hartley) guinea-pigs weighing 350-380 g and 30 splenectomized guinea-pigs were exposed to simulated hypobaric hypoxia of 50.6 kPa (equal to an altitude of 5486 m) for 14 days. The partial pressure of oxygen was set at half that at sea level. The white blood cell count increased significantly on day 3 of the simulated high altitude experiment but returned to normal on day 7, whereas the red blood cell count increased continuously. To study the effect of high altitude exposure on platelets, the platelet count in the splenectomized group was compared to that in a non-splenectomized group. Investigation of the resistance of red blood cell membranes to osmotic pressure under hypobaric conditions revealed a shift of the onset of haemolysis in the hyperosmotic direction. These findings may help to increase our understanding of the biochemical mechanisms of adaptation to hypobaric hypoxia.

Smooth Muscle Cells Isolated from Thoracic Aortic Aneurysms Exhibit Increased Genomic Damage, but Similar Tendency for Apoptosis

PubMed Central

Serhatli, Muge; Kacar, Omer; Adiguzel, Zelal; Tuncer, Altug; Hayran, Mutlu; Baysal, Kemal

2012-01-01

Aortic aneurysms (AA) are characterized by structural deterioration leading to progressive dilation. During the development of AA, two key structural changes are pronounced, one being degradation of extracellular matrix and the other loss of smooth muscle cells (SMCs) through apoptosis. Reactive oxygen species (ROS) are produced above physiological levels in dilated (aneurismal) part of the aorta compared to the nondilated part and they are known to be associated with both the extracellular matrix degradation and the loss of SMCs. In this study, we hypothesized that aneurismal SMCs are more prone to apoptosis and that at least some cells undergo apoptosis due to elevated ROS in the aortic wall. To test this hypothesis, we first isolated SMCs from thoracic aneurismal tissue and compared their apoptotic tendency with normal SMCs in response to H2O2, oxidized sterol, or UV treatment. Exposed cells exhibited morphological changes characteristic of apoptosis, such as cell shrinkage, membrane blebbing, chromatin condensation, and DNA fragmentation. Terminal deoxynucleotidyl transferased UTP nick end labeling (TUNEL) further confirmed the fragmentation of nuclear DNA in these cells. Vascular SMCs were analyzed for their micronuclei (MN) and binucleate (BN) frequency as indicators of genomic abnormality. These data were then compared to patient parameters, including age, gender, hypertension, or aortic diameter for existing correlations. While the tendency for apoptosis was not significantly different compared to normal cells, both the %MN and %BN were higher in aneurismal SMCs. The data suggest that there is increased DNA damage in TAA samples, which might play a pivotal role in disease development. PMID:22871164

Cytokine production as a putative biological mechanism underlying stress sensitization in high combat exposed soldiers.

PubMed

Smid, Geert E; van Zuiden, Mirjam; Geuze, Elbert; Kavelaars, Annemieke; Heijnen, Cobi J; Vermetten, Eric

2015-01-01

Combat stress exposed soldiers may respond to post-deployment stressful life events (SLE) with increases in symptoms of posttraumatic stress disorder (PTSD), consistent with a model of stress sensitization. Several lines of research point to sensitization as a model to describe the relations between exposure to traumatic events, subsequent SLE, and symptoms of PTSD. Based on previous findings we hypothesized that immune activation, measured as a high in vitro capacity of leukocytes to produce cytokines upon stimulation, underlies stress sensitization. We assessed mitogen-induced cytokine production at 1 month, SLE at 1 year, and PTSD symptoms from 1 month up to 2 years post-deployment in soldiers returned from deployment to Afghanistan (N=693). Exploratory structural equation modeling as well as latent growth models were applied. The data demonstrated significant three-way interaction effects of combat stress exposure, cytokine production, and post-deployment SLE on linear change in PTSD symptoms over the first 2 years following return from deployment. In soldiers reporting high combat stress exposure, both high mitogen-stimulated T-cell cytokine production and high innate cytokine production were associated with increases in PTSD symptoms in response to post-deployment SLE. In low combat stress exposed soldiers as well as those with low cytokine production, post-deployment SLE were not associated with increases in PTSD symptoms. High stimulated T-cell and innate cytokine production may contribute to stress sensitization in recently deployed, high combat stress exposed soldiers. These findings suggest that detecting and eventually normalizing immune activation may potentially complement future strategies to prevent progression of PTSD symptoms following return from deployment. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Protective effects of WR2721 on early bone marrow hematopoietic function in mice exposed to 6.5 Gy of (60)Co γ-rays].

PubMed

Deng, Zi-Liang; Zhang, Liu-Zhen; Cong, Yue; Liu, Xiao-Lan; Yu, Zu-Ying; Shan, Ya-Jun; Cui, Yu; Wang, Li-Mei; Xing, Shuang; Cong, Yu-Wen; Luo, Qing-Liang

2014-06-01

The aim of this study was to investigate the effect of WR2721(amifostine) against bone marrow hematopoietic damage of mice exposed to 6.5 Gy of (60)Co-γ ray. A total of 60 C57/BL6J mice was divided into 3 groups:normal group (mice were injected with physiological salt solution), irradiation group (mice were injected with physiologic salt solution before irradiation) and WR2721 group (mice were injected with WR2721 before irradiation). The WBC, neutrophil (Neut), Plt and RBC levels in peripheral blood of 3 group mice were counted within 60 days after irradiation; the bone marrow nuclear cells (BMNC) were counted at 2 and 24 hours after irradiation; the hematopoietic stem/progenitor cell (LK/LSK) level and colony formation capability were detected by flow cytometry at 2 and 24 hours after irradiation. The results indicated that the counts of WBC and neut at 4 and 18 days, Plt at 7-18 days and RBC at 10-30 day after irradiation in WR2721 group were higher than those in irradiation group (P < 0.05); the BMNC, LSK and LK levels obviously increased at 24 hours after irradiation (P < 0.05), the CFU-GEMM, CFU-GM, CFU-MK BFU-E and CFU-E all significantly increased at 2 and 24 hours after irradiation (P < 0.01), as compared with irradiation group. It is concluded that WR2721 can effectively alleviate early hematopoietic damage and promote the fast recovery of peripheral blood cells in mice exposed to γ-ray, suggesting that the WR2721 has significant radioprotective effect on hematopoietic system.

Oxidative Stress and Aromatic Hydrocarbon Response of Human Bronchial Epithelial Cells Exposed to Petro- or Biodiesel Exhaust Treated with a Diesel Particulate Filter

PubMed Central

Hawley, Brie; L'Orange, Christian; Olsen, Dan B.; Marchese, Anthony J.; Volckens, John

2014-01-01

The composition of diesel exhaust has changed over the past decade due to the increased use of alternative fuels, like biodiesel, and to new regulations on diesel engine emissions. Given the changing nature of diesel fuels and diesel exhaust emissions, a need exists to understand the human health implications of switching to “cleaner” diesel engines run with particulate filters and engines run on alternative fuels like biodiesel. We exposed well-differentiated normal human bronchial epithelial cells to fresh, complete exhaust from a diesel engine run (1) with and without a diesel particulate filter and (2) using either traditional petro- or alternative biodiesel. Despite the lowered emissions in filter-treated exhaust (a 91–96% reduction in mass), significant increases in transcripts associated with oxidative stress and polycyclic aromatic hydrocarbon response were observed in all exposure groups and were not significantly different between exposure groups. Our results suggest that biodiesel and filter-treated diesel exhaust elicits as great, or greater a cellular response as unfiltered, traditional petrodiesel exhaust in a representative model of the bronchial epithelium. PMID:25061111

5-Fluorouracil-induced apoptosis in cultured oral cancer cells.

PubMed

Tong, D; Poot, M; Hu, D; Oda, D

2000-03-01

Chemotherapy is commonly used to treat advanced oral squamous cell carcinoma (SCC) and is known to kill cancer cells through apoptosis. Our hypothesis states that 5-fluorouracil (5FU) also kills cultured oral epithelial cells through programmed cell death or apoptosis. Cultured oral cancer cells were exposed to an optimum dose of 20 mg/ml of 5FU. Cells were analyzed for changes in cell cycle distribution and induction of cell death including apoptosis. Normal control, human papilloma virus-immortalized (PP), ATCC SCC cell line (CA1) and two primary oral SCC cell lines (CA3 and -4) were studied. Inhibition of apoptosis by a pan-caspase inhibitor was used. SYTO 11 flow cytometry showed increased apoptosis in all 5FU-treated cell cultures compared to untreated controls. The results show biological variation in apoptotic response. CA1 had the lowest apoptotic rate of the cancer cell lines at 1.5%. Next lowest was CA3, followed by CA4 and PP. In addition, alteration in the G1 and S phase fractions were found. Untreated CA1 showed 28% G1, 53% S compared to 43% G1, and 40% S of treated. We investigated the pathway of apoptosis using the pan-caspase inhibitor IDN-1529 by methylthiazolyl diphenyl tetrazolium bromide (MTT) colorimetric analysis. Results showed mild inhibition of cell death when cells were incubated with 50 microM IDN-1529 for 24 h. This suggests a probable caspase-dependent apoptotic pathway. In conclusion, our data suggest that 5FU induces oral cancer cell death through apoptosis and that biological variation exists between normal and cancer cells and between different types of cancer cells themselves. Our data indicate that cultures of a useful in vitro model for chemosensitivity assays are possible. Our results also suggest a caspase-dependent pathway for chemocytotoxicity in oral SCC.

Effects of 60-Hz electric fields on serotonin metabolism in the rat pineal gland

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

Anderson, L.E.; Hilton, D.I.; Phillips, R.D.

Serotonin and two of its metabolites, melatonin and 5-methoxytryptophol, exhibit circadian rhythmicity in the pineal gland. We recently reported a marked reduction in the normal night-time increase in melatonin concentration in the pineal glands of rats exposed to 60-Hz electric fields. Concomitant with the apparent abolition of melatonin rhythmicity, serotonin-N-acetyl transferase (SNAT) activity was suppressed. We have now conducted studies to determine if abolition of the rhythm in melatonin production in electric-field-exposed rats arises solely from interference in SNAT activity, or if the availability of pineal serotonin is a factor that is affected by exposure. Pineal serotonin concentrations were comparedmore » in rats that were either exposed or sham exposed to 65 kV/m for 30 days. Sham-exposed animals exhibited normal diurnal rhythmicity for pineal concentrations of both melatonin and serotonin; melatonin levels increased markedly during the dark phase with a concurrent decrease in serotonin levels. In the exposed animals, however, normal serotonin rhythmicity was abolished; serotonin levels in these animals did not increase during the light period. The conclusion that electric field exposure results in a biochemical alteration in SNAT enzyme activity can be inferred from the loss of both serotonin and melatonin rhythmicity, as well as by direct measurement of SNAT activity itself. 35 references, 3 figures, 1 table.« less

Effects of artificial illumination on turkey sperm viability.

PubMed

Williams, C J; Siopes, T D

1985-12-01

The effects of direct exposure of turkey semen to artificial lighting on the quality of the spermatozoa were investigated. Undiluted (neat) and diluted semen were exposed to light or dark treatments for 4 or 6 hr while held at 5, 15, or 25 C. The percentage of normal, abnormal and dead sperm, and the percent fertility was determined after various light and dark treatments. Neat semen held in light at 5, 15, and 25 C, and dilute semen held at 5 and 25 C, contained significantly greater numbers of normal spermatozoa than semen exposed to the dark. A significant rise in the number of abnormal and dead spermatozoa was seen in treated samples held in the dark. Both neat and extended semen exposed to blue light (peak 450 nm) contained significantly greater numbers of normal spermatozoa and fewer abnormal spermatozoa than semen treated with red light (peak 650 nm) after both 4 and 6 hr of treatment. The fertilizing capacity of spermatozoa exposed to light was greater than that of spermatozoa exposed to dark. Artificial insemination of hens with semen exposed to light or darkness for 6 hr resulted in an initial percentage of fertile eggs of about 40% and 24% from the light and dark treated semen, respectively. It was concluded that light resulted in improved quality of turkey semen during a short-term holding period.

GDF-15 is abundantly expressed in plexiform lesions in patients with pulmonary arterial hypertension and affects proliferation and apoptosis of pulmonary endothelial cells

PubMed Central

2011-01-01

Background Growth-differentiation factor-15 (GDF-15) is a stress-responsive, transforming growth factor-β-related cytokine, which has recently been reported to be elevated in serum of patients with idiopathic pulmonary arterial hypertension (IPAH). The aim of the study was to examine the expression and biological roles of GDF-15 in the lung of patients with pulmonary arterial hypertension (PAH). Methods GDF-15 expression in normal lungs and lung specimens of PAH patients were studied by real-time RT-PCR and immunohistochemistry. Using laser-assisted micro-dissection, GDF-15 expression was further analyzed within vascular compartments of PAH lungs. To elucidate the role of GDF-15 on endothelial cells, human pulmonary microvascular endothelial cells (HPMEC) were exposed to hypoxia and laminar shear stress. The effects of GDF-15 on the proliferation and cell death of HPMEC were studied using recombinant GDF-15 protein. Results GDF-15 expression was found to be increased in lung specimens from PAH patients, com-pared to normal lungs. GDF-15 was abundantly expressed in pulmonary vascular endothelial cells with a strong signal in the core of plexiform lesions. HPMEC responded with marked upregulation of GDF-15 to hypoxia and laminar shear stress. Apoptotic cell death of HPMEC was diminished, whereas HPMEC proliferation was either increased or decreased depending of the concentration of recombinant GDF-15 protein. Conclusions GDF-15 expression is increased in PAH lungs and appears predominantly located in vascular endothelial cells. The expression pattern as well as the observed effects on proliferation and apoptosis of pulmonary endothelial cells suggest a role of GDF-15 in the homeostasis of endothelial cells in PAH patients. PMID:21548946

Novel anticancer agent, benzyldihydroxyoctenone, isolated from Streptomyces sp. causes G1 cell cycle arrest and induces apoptosis of HeLa cells.

PubMed

Lee, Chul-Hoon; Lim, Haeyoung; Moon, Sangik; Shin, Choonshik; Kim, Seunghyun; Kim, Bum-Joon; Lim, Yoongho

2007-06-01

In the course of screening for anticancer agents, a novel active compound, F3-2-5, was isolated from culture broth of Streptomyces sp., KACC91015. Its structure was identified using nuclear magnetic resonance, mass spectrometry, and molecular modeling experiments, and confirmed by total synthesis. The growth of various human cancer cell lines was inhibited in a dose-dependent manner by 0.06-0.48 mM F3-2-5 over 24 h. Its IC(50) values were estimated at 37 microM on HeLa, 72 microM on A549, and 190 microM on HT-29 cells. However, F3-2-5 had no antiproliferative effect on normal lymphocytes and normal fibroblasts used as controls. Moreover, it affected cell cycle regulation and caused apoptosis of the HeLa cells; chromatin condensation and DNA fragmentation were observed in cells exposed to 80 microM F3-2-5. Western blot analysis revealed that F3-2-5 inhibited phosphorylation of retinoblastoma protein (pRb) and reduced expression of cyclin-dependent kinase-4 and -6, and cyclin D1 and E, while levels of p53 and p21(WAF1/CIP1) increased. Taken together, these findings show that F3-2-5 inhibits proliferation of HeLa cells by inducing G(1) phase arrest as a consequence of inhibition of pRb phosphorylation following up-regulation of p21(WAF1/CIP1) and p53. Furthermore, apoptosis in HeLa cells treated with F3-2-5 was associated with an increase in Bax and p53, leading to release of cytochrome c, activation of caspase-3, and -8, and cleavage of poly (ADP-ribose) polymerase.

Enhanced constitutive invasion activity in human nontumorigenic keratinocytes exposed to a low level of barium for a long time.

PubMed

Thang, Nguyen D; Yajima, Ichiro; Ohnuma, Shoko; Ohgami, Nobutaka; Kumasaka, Mayuko Y; Ichihara, Gaku; Kato, Masashi

2015-02-01

We have recently demonstrated that exposure to barium for a short time (≤4 days) and at a low level (5 µM = 687 µg/L) promotes invasion of human nontumorigenic HaCaT cells, which have characteristics similar to those of normal keratinocytes, suggesting that exposure to barium for a short time enhances malignant characteristics. Here we examined the effect of exposure to low level of barium for a long time, a condition mimicking the exposure to barium through well water, on malignant characteristics of HaCaT keratinocytes. Constitutive invasion activity, focal adhesion kinase (FAK) protein expression and activity, and matrix metalloproteinase 14 (MMP14) protein expression in primary cultured normal human epidermal keratinocytes, HaCaT keratinocytes, and HSC5 and A431 human squamous cell carcinoma cells were augmented following an increase in malignancy grade of the cells. Constitutive invasion activity, FAK phosphorylation, and MMP14 expression levels of HaCaT keratinocytes after treatment with 5 µM barium for 4 months were significantly higher than those of control untreated HaCaT keratinocytes. Taken together, our results suggest that exposure to a low level of barium for a long time enhances constitutive malignant characteristics of HaCaT keratinocytes via regulatory molecules (FAK and MMP14) for invasion. © 2013 Wiley Periodicals, Inc.

Occupational exposure to formaldehyde and alterations in lymphocyte subsets

PubMed Central

Hosgood, H. Dean; Zhang, Luoping; Tang, Xiaojiang; Vermeulen, Roel; Hao, Zhenyue; Shen, Min; Qiu, Chuangyi; Ge, Yichen; Hua, Ming; Ji, Zhiying; Li, Senhua; Xiong, Jun; Reiss, Boris; Liu, Songwang; Xin, Kerry X.; Azuma, Mariko; Xie, Yuxuan; Freeman, Laura Beane; Ruan, Xiaolin; Guo, Weihong; Galvan, Noe; Blair, Aaron; Li, Laiyu; Huang, Hanlin; Smith, Martyn T.; Rothman, Nathaniel; Lan, Qing

2012-01-01

Background Formaldehyde is used in many occupational settings, most notably in manufacturing, health care, and embalming. Formaldehyde has been classified as a human carcinogen, but its mechanism of action remains uncertain. Methods We carried out a cross-sectional study of 43 formaldehyde exposed-workers and 51 unexposed age and sex-matched controls in Guangdong, China to study formaldehyde’s early biologic effects. To follow-up our previous report that the total lymphocyte count was decreased in formaldehyde-exposed workers compared to controls, we evaluated each major lymphocyte subset (i.e., CD4+ T cells, CD8+ T cells, natural killer (NK) cells, and B cells) and T cell lymphocyte subset (CD4+ naïve and memory T cells, CD8+ naïve and memory T cells, and regulatory T cells). Linear regression of each subset was used to test for differences between exposed workers and controls, adjusting for potential confounders. Results Total NK cell and T cell counts were about 24% (p=0.037) and 16% (p=0.0042) lower, respectively, among exposed workers. Among certain T cell subsets, decreased counts among exposed workers were observed for CD8+ T cells (p=0.026), CD8+ effector memory T cells (p=0.018), and regulatory T cells (CD4+FoxP3+: p=0.04; CD25+FoxP3+: p=0.008). Conclusions Formaldehyde exposed-workers experienced decreased counts of NK cells, regulatory T cells, and CD8+ effector memory T cells; however, due to the small sample size these findings need to be confirmed in larger studies. PMID:22767408

Lung fibroblasts may play an important role in clearing apoptotic bodies of bronchial epithelial cells generated by exposure to PHMG-P-containing solution.

PubMed

Park, Eun-Jung; Park, Sung-Jin; Kim, Sanghwa; Lee, Kyuhong; Chang, Jaerak

2018-04-01

Polyhexamethylene guanidine (PHMG) has been widely used in the industry owing to its excellent biocidal, anti-corrosive, and anti-biofouling properties. In Korea, consumers exposed to PHMG-phosphate (PHMG-P)-containing humidifier disinfectant have begun to suffer from fibrotic lung injury-related symptoms for unknown reasons. However, no appropriate treatment has yet been found because the detail toxic mechanism has not been identified. Herein, we first studied the toxic mechanism of PHMG-P-containing solution using human normal bronchial epithelial cells (BEAS-2B cells). When exposed for 24 h, PHMG-P-containing solution rapidly decreased cell viability from around 6 h after exposure and significantly increased of the phosphatidylserine exposure and the LDH release. At 6 h of exposure, the material contained in the solution was found to be bound to the cell membrane and the inner wall of vacuoles, and damaged the cell membrane and organelles. In addition, a significant increase of IFN-γ was observed among cytokines, the expression of apoptosis-, autophagy-, and membrane and DNA damage-related proteins was also enhanced. Meanwhile, the level of intracellular ROS and the secretion of IL-8 and CXCL-1, which are chemokines for professional phagocytes, decreased. Thus, we treated dead BEAS-2B cells to lung fibroblasts (HFL-1), non-professional phagocytes, and then we observed that the dead cells rapidly attached to HFL-1 cells and were taken up. Additionally, increased secretion of IL-8 and CXCL-1 was observed in the cells. Based on these results, we suggest that pulmonary exposure to PHMG-P induces apoptosis of bronchial epithelial cells and lung fibroblasts might play an important role in the clearance of the apoptotic debris. Copyright © 2018 Elsevier B.V. All rights reserved.

The same drug but a different mechanism of action: comparison of free doxorubicin with two different N-(2-hydroxypropyl)methacrylamide copolymer-bound doxorubicin conjugates in EL-4 cancer cell line.

PubMed

Kovár, Lubomír; Strohalm, Jirí; Chytil, Petr; Mrkvan, Tomás; Kovár, Marek; Hovorka, Ondrej; Ulbrich, Karel; Ríhová, Blanka

2007-01-01

Doxorubicin is one of the most potent anti-tumor drugs with a broad spectrum of use. To reduce its toxic effect and improve its pharmacokinetics, we conjugated it to an HPMA copolymer carrier that enhances its passive accumulation within solid tumors via the EPR effect and decreases its cytotoxicity to normal, noncancer cells. In this study, we compared the antiproliferative, pro-survival, and death signals triggered in EL-4 cancer cells exposed to free doxorubicin and doxorubicin conjugated to a HPMA copolymer carrier via either enzymatically (PK1) or hydrolytically (HYD) degradable bonds. We have previously shown that the intracellular distribution of free doxorubicin, HYD, and PK1 is markedly different. Here, we demonstrated that these three agents greatly differ also in the antiproliferative effect and cell death signals they trigger. JNK phosphorylation sharply increased in cells treated with HYD, while treatment with free doxorubicin moderately decreased and treatment with PK1 even strongly decreased it. On the other hand, treatment with free doxorubicin greatly increased p38 phosphorylation, while PK1 and HYD increased it slightly. PK1 also significantly increased ERK phosphorylation, while both the free doxorubicin and HYD conjugate slightly decreased it. Long-term inhibition of JNK significantly increased both proliferation and viability of EL-4 cells treated with free doxorubicin, showing that the JNK signaling pathway could be critical for mediating cell death in EL-4 cells exposed to free doxorubicin. Both activation of caspase 3 and decreased binding activity of the p50 subunit of NFkappaB were observed in cells treated with free doxorubicin and HYD, while no such effects were seen in cells incubated with PK1. Analysis of the expression of genes involved in apoptosis and regulation of the cell cycle demonstrated that free doxorubicin and HYD have very similar mechanisms of action, while PK1 has very different characteristics.

Effects of anhydrous ammonia on a forest ecosystem

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

Dale, E.E. Jr.

1976-01-01

A forest ecosystem covering 26 square miles was exposed to anhydrous ammonia following a pipeline rupture in June, 1971. Initial effects included death or defoliation of vegetation and high nitrate accumulations in plant tissues, soils, and natural waters. Deciduous trees and herbaceous species had recovered one year after exposure and soil and water conditions were near normal, but Pinus echinata and Juniperous virginiana showed loss of needles, abnormal twig growth and low cone production after three years. Ammonia or ammonium hydroxide entered plants primarily through stomates and caused injury by desiccation, nutritional imbalances, and other alterations in cell conditions.

Strain H2-419-4 of Haematococcus pluvialis induced by ethyl methanesulphonate and ultraviolet radiation

NASA Astrophysics Data System (ADS)

Sun, Yanhong; Liu, Jianguo; Zhang, Xiaoli; Lin, Wei

2008-05-01

Two strains H2-410 and H2-419 were obtained from the chemically mutated survivors of wild Haematococcus pluvialis 2 by using ethyl methanesulphonate (EMS). Strains H2-410 and H2-419 showed a fast cell growth with 13% and 20% increase in biomass compared to wild type, respectively. Then H2-419-4, a fast cell growth and high astaxanthin accumulation strain, was obtained by exposing the strain H2-419 to ultraviolet radiation (UV) further. The total biomass, the astaxanthin content per cell, astaxanthin production of H2-419-4 showed 68%, 28%, and 120% increase compared to wild H. pluvialis 2, respectively. HPLC (High Performance Liquid Chromatography) data showed also an obvious proportional variation of different carotenoid compositions in the extracts of H2-419-4 and the wild type, although no peak of carotenoids appeared or disappeared. Therefore, the main compositions in strain H2-419-4, like its wild one, were free of astaxanthin, monoester, and diester of astaxanthin. The asexual reproduction in survivors after exposed to UV was not synchronous, and different from the normal synchronous asexual reproduction as the mother cells were motile instead of non-motile. Interestingly, some survivors from UV irradiation produced many mini-spores (or gamete?), the spores moved away from the mother cell gradually 4 or 5 days later. This is quite similar to sexual reproduction described by Elliot in 1934. However, whether this was sexual reproduction remains questionable, as no mating process has been observed.

Cellular glucose-6-phosphate dehydrogenase (G6PD) status modulates the effects of nitric oxide (NO) on human foreskin fibroblasts.

PubMed

Cheng, M L; Ho, H Y; Liang, C M; Chou, Y H; Stern, A; Lu, F J; Chiu, D T

2000-06-23

Glucose-6-phosphate dehydrogenase (G6PD) plays an important role in cellular redox homeostasis, which is crucial for cell survival. In the present study, we found that G6PD status determines the response of cells exposed to nitric oxide (NO) donor. Treatment with NO donor, sodium nitroprusside (SNP), caused apoptosis in G6PD-deficient human foreskin fibroblasts (HFF1), whereas it was growth stimulatory in the normal counterpart (HFF3). Such effects were abolished by NO scavengers like hemoglobin. Ectopic expression of G6PD in HFF1 cells switched the cellular response to NO from apoptosis to growth stimulation. Experiments with 1H-¿1,2,4ŏxadiazolo¿4, 3-aquinoxalin-1-one and 8-bromo-cGMP showed that the effects of NO on HFF1 and HFF3 cells were independent of cGMP signalling pathway. Intriguingly, trolox prevented the SNP-induced apoptosis in HFF1 cells. These data demonstrate that G6PD plays a critical role in regulation of cell growth and survival.

Interactions of Histophilus somni with Host Cells.

PubMed

Behling-Kelly, Erica; Rivera-Rivas, Jose; Czuprynski, Charles J

2016-01-01

Histophilus somni resides as part of the normal microflora in the upper respiratory tract of healthy cattle. From this site, the organism can make its way into the lower respiratory tract, where it is one of the important bacterial agents of the respiratory disease complex. If H. somni cells disseminate to the bloodstream, they frequently result in thrombus formation. A series of in vitro investigations have examined potential mechanisms that might contribute to such thrombus formation. Earlier work showed that H. somni can stimulate some bovine endothelial cells to undergo apoptosis. More recent studies indicate that H. somni stimulates endothelial cell tissue factor activity and disrupts intercellular junctions. The net effect is to enhance procoagulant activity on the endothelium surface and to make the endothelial monolayer more permeable to molecules, leukocytes, and perhaps H. somni cells. H. somni also activates bovine platelets, which also can enhance tissue factor activity on the endothelium surface. When exposed to H. somni, bovine neutrophils and mononuclear phagocytes form extracellular traps in vitro. Ongoing research is investigating how the interplay among endothelial cells, platelets, and leukocytes might contribute to the thrombus formation seen in infected cattle.

Changes in the biomechanical properties of a single cell induced by nonthermal atmospheric pressure micro-dielectric barrier discharge plasma.

PubMed

Choi, Hyeongwon; Choi, Eun Ha; Kim, Kyung Sook

2017-10-01

Mechanical properties of a single cell are closely related to the fate and functions of the cell. Changes in mechanical properties may cause diseases or cell apoptosis. Selective cytotoxic effects of nonthermal atmospheric pressure micro-dielectric barrier discharge (DBD) plasma have been demonstrated on cancer cells. In this work, changes in the mechanical properties of a single cell induced by nonthermal atmospheric pressure micro-DBD plasma were investigated using atomic force microscopy (AFM). Two cervical cancer cell lines (HeLa and SiHa) and normal human fibroblast cells (HFBs) were exposed to micro-DBD plasma for various exposure times. The elasticity of a single cell was determined by force-distance curve measurement using AFM. Young's modulus was decreased by plasma treatment for all cells. The Young's modulus of plasma-treated HeLa cells was decreased by 75% compared to nontreated HeLa cells. In SiHa cells and HFBs, elasticity was decreased slightly. Chemical changes induced by the plasma treatment, which were observed by Raman spectroscopy, were also significant in HeLa cells compared to SiHa cells and HFBs. These results suggested that the molecular changes induced by micro-DBD plasma were related to cell mechanical changes. © 2017 Wiley Periodicals, Inc.

Response of the iron-deficient erythrocyte in the rat to hyperoxia

NASA Technical Reports Server (NTRS)

Larkin, E. C.; Kimzey, S. L.; Siler, K.

1978-01-01

Normal and iron-deficient rats were exposed to 90% O2 at 760 Torr for 24 or 48 h. Erythrocyte response to hyperoxia was monitored by potassium (rubidium) influx studies, by storage stress, and by ultrastructural studies. Normal rat erythrocytes exhibited morphological changes and decrease of ouabain-sensitive potassium influx compared to unexposed controls. Both components of erythrocyte potassium influx were affected by iron deficiency. Erythrocytes from unexposed iron-deficient rats showed a 50% increase in ouabain-sensitive potassium influx compared to controls. Iron-deficient rats exposed to hyperoxia for 24 or 48 h, had erythrocytes with morphological changes. Erythrocytes of iron-deficient rats exposed for 24 h showned no influx change; those exposed for 48 h showed a decrease of ouabain-sensitive influx compared to erythrocytes of controls.

Oncolytic effects of adenovirus mutant capable of replicating in hypoxic and normoxic regions of solid tumor.

PubMed

Cho, Won-Kyung; Seong, Young Rim; Lee, Yeune Hee; Kim, Min Ji; Hwang, Kyung-Sun; Yoo, Jinsang; Choi, Seeyoung; Jung, Cho-Rok; Im, Dong-Soo

2004-11-01

Solid tumors contain normoxic and hypoxic regions depending on the distance from the capillary. Normal cells may also be exposed to hypoxia under certain physiological conditions. Tumor hypoxia has been shown to associate strongly with tumor propagation and malignant progression. Hypoxia-inducible factor (HIF)-1alpha is stable under hypoxia and induces transcription of target genes by binding to the hypoxia-response element (HRE). Here we investigated the oncolytic effects of a novel adenovirus mutant with a deleted E1B55 gene (Ad.Delta55.HRE), in which the expression of E1A, which is essential for adenoviral replication, is regulated under the control of an HRE-expression system. Ad.Delta55.HRE expressed E1A under normoxia and more E1A under hypoxia and exhibited oncolytic effects on various cultured tumor cells, but its cytotoxic effect is relatively attenuated in normal fibroblast cells under normoxic and hypoxic conditions. Ad.Delta55.HRE lysed Huh-7 hepatoma cells stably expressing HIF-1alpha more effectively compared to parental cells. Ad.Delta55.HRE treatment exhibited significant antitumor activity in PC-3 prostate- and MDA-MB-435 breast tumor-bearing nude mice in which HIF-1alpha protein was immunohistochemically detected. The E1A and hexon proteins of adenovirus were immunostained in MDA-MB-435 xenografts after Ad.Delta55.HRE treatment, suggestive of viral replication. Our results suggest that Ad.Delta55.HRE may be useful for the treatment of solid tumors.

Evaluation of possible health risk associated with occupational exposure to formaldehyde

NASA Astrophysics Data System (ADS)

Vargova, Maria; Janota, Stanislav; Karelova, Jarmila; Barancokova, Maria; Sulcova, Margita

1993-03-01

Widespread us of formaldehyde in a variety of applications is known to result in appreciable exposure of workers and large segments of the general population. Because of possible genotoxic and immunotoxic effects, we investigated the health condition of people occupationally exposed to formaldehyde in a plant in which woodsplinter materials are manufactured. The concentration of formaldehyde in the workplace was greater than the average and peak concentrations of formaldehyde in Czechoslovakia (0.5 mg/m3 and 1 mg/m3 respectively). Selected parameters of genotoxicity (cytogenetic analysis, nucleolus test) and immunotoxocity (serum immunoglobulin G, A, M; complement C3, C4; alpha-1-anti-trypsine, alpha-2 macroglobulin, ceruloplasmin, transferrin, prealbumin, orosomucoid levels) were determined. The results of the evaluation of mitotic indices and the blastogen transformation point to an effect of the exposure to formaldehyde on r-RNA synthesis inhibition and lymphocyte maturation decrease. The frequency of aberrant cells in the peripheral blood lymphocytes was increased in both, exposed and control group and was above 1.2 - 2% of aberrant cells observed in the normal population in Czechoslovakia. There was no significant differences in the values of natural immunity and specific humoral immunity. Significant differences were observed in the values of mitogen-induced proliferation of lymphocytes between the exposed and the matching and background control groups. These changes are considered to be sensitive indicators of the potential effects on the integrity of a more important immunologic function.

MnTnBuOE-2-PyP protects normal colorectal fibroblasts from radiation damage and simultaneously enhances radio/chemotherapeutic killing of colorectal cancer cells

PubMed Central

Kosmacek, Elizabeth A.; Chatterjee, Arpita; Tong, Qiang; Lin, Chi; Oberley, Rebecca E.

2016-01-01

Manganese porphyrins have been shown to be potent radioprotectors in a variety of cancer models. However, the mechanism as to how these porphyrins protect normal tissues from radiation damage still remains largely unknown. In the current study, we determine the effects of the manganese porphyrin, MnTnBuOE-2-PyP, on primary colorectal fibroblasts exposed to irradiation. We found that 2 Gy of radiation enhances the fibroblasts' ability to contract a collagen matrix, increases cell size and promotes cellular senesence. Treating fibroblasts with MnTnBuOE-2-PyP significantly inhibited radiation-induced collagen contraction, preserved cell morphology and also inhibited cellular senescence. We further showed that MnTnBuOE-2-PyP enhanced the overall viability of the fibroblasts following exposure to radiation but did not protect colorectal cancer cell viability. Specifically, MnTnBuOE-2-PyP in combination with irradiation, caused a significant decrease in tumor clonogenicity. Since locally advanced rectal cancers are treated with chemoradiation therapy followed by surgery and non-metastatic anal cancers are treated with chemoradiation therapy, we also investigated the effects of MnTnBuOE-2-PyP in combination with radiation, 5-fluorouracil with and without Mitomycin C. We found that MnTnBuOE-2-PyP in combination with Mitomycin C or 5-fluorouracil further enhances those compounds' ability to suppress tumor cell growth. When MnTnBuOE-2-PyP was combined with the two chemotherapeutics and radiation, we observed the greatest reduction in tumor cell growth. Therefore, these studies indicate that MnTnBuOE-2-PyP could be used as a potent radioprotector for normal tissue, while at the same time enhancing radiation and chemotherapy treatment for rectal and anal cancers. PMID:27119354

MnTnBuOE-2-PyP protects normal colorectal fibroblasts from radiation damage and simultaneously enhances radio/chemotherapeutic killing of colorectal cancer cells.

PubMed

Kosmacek, Elizabeth A; Chatterjee, Arpita; Tong, Qiang; Lin, Chi; Oberley-Deegan, Rebecca E

2016-06-07

Manganese porphyrins have been shown to be potent radioprotectors in a variety of cancer models. However, the mechanism as to how these porphyrins protect normal tissues from radiation damage still remains largely unknown. In the current study, we determine the effects of the manganese porphyrin, MnTnBuOE-2-PyP, on primary colorectal fibroblasts exposed to irradiation. We found that 2 Gy of radiation enhances the fibroblasts' ability to contract a collagen matrix, increases cell size and promotes cellular senesence. Treating fibroblasts with MnTnBuOE-2-PyP significantly inhibited radiation-induced collagen contraction, preserved cell morphology and also inhibited cellular senescence. We further showed that MnTnBuOE-2-PyP enhanced the overall viability of the fibroblasts following exposure to radiation but did not protect colorectal cancer cell viability. Specifically, MnTnBuOE-2-PyP in combination with irradiation, caused a significant decrease in tumor clonogenicity. Since locally advanced rectal cancers are treated with chemoradiation therapy followed by surgery and non-metastatic anal cancers are treated with chemoradiation therapy, we also investigated the effects of MnTnBuOE-2-PyP in combination with radiation, 5-fluorouracil with and without Mitomycin C. We found that MnTnBuOE-2-PyP in combination with Mitomycin C or 5-fluorouracil further enhances those compounds' ability to suppress tumor cell growth. When MnTnBuOE-2-PyP was combined with the two chemotherapeutics and radiation, we observed the greatest reduction in tumor cell growth. Therefore, these studies indicate that MnTnBuOE-2-PyP could be used as a potent radioprotector for normal tissue, while at the same time enhancing radiation and chemotherapy treatment for rectal and anal cancers.

Nucleolar Organizer Regions of Oral Epithelial Cells in Crack Cocaine Users

PubMed Central

Carvalho de M. Thiele, Magna; Carlos Bohn, Joslei; Lima Chaiben, Cassiano; Trindade Grégio, Ana Maria; Ângela Naval Machado, Maria; Adilson Soares de Lima, Antonio

2013-01-01

Background: The health risks of crack cocaine smoking on the oral mucosa has not been widely researched and documented. Objective: The purpose of this study was to analyze the proliferative activity of oral epithelial cells exposed to crack cocaine smoke using silver nucleolar organizer region (AgNOR) staining. Methods: Oral smears were collected from clinically normal-appearing buccal mucosa by liquid-based exfoliative cytology of 60 individuals (30 crack cocaine users and 30 healthy controls matched for age and gender) and analyzed for cytomorphologic and cytomorphometric techniques. Results: Crack cocaine users consumed about 13.3 heat-stable rocks per day and the time consumption of the drug was of 5.2 (± 3.3) years. Mean values of AgNOR counting for case and control groups were 5.18 ± 1.83 and 3.38 ± 1.02 (P<0.05), respectively. AgNOR area and percentage of AgNOR-occupied nuclear area were increased in comparison with the control (P<0.05). There was no statistically significant difference in the mean values of the nuclear area between the groups (P>0.05). Conclusion: This study revealed that crack cocaine smoke increases the rate of cellular proliferation in cells of normal buccal mucosa. PMID:23567853

[DNA microarray reveals changes in gene expression of endothelial cells under shear stress].

PubMed

Cheng, Min; Zhang, Wensheng; Chen, Huaiqing; Wu, Wenchao; Huang, Hua

2004-04-01

cDNA microarray technology is used as a powerful tool for rapid, comprehensive, and quantitative analysis of gene profiles of cultured human umbilical vein endothelial cells(HUVECs) in the normal static group and the shear stressed (4.20 dyne/cm2, 2 h) group. The total RNA from normal static cultured HUVECs was labeled by Cy3-dCTP, and total RNA of HUVECs from the paired shear stressed experiment was labeled by Cy5-dCTP. The expression ratios reported are the average from the two separate experiments. After bioinformatics analysis, we identified a total of 108 genes (approximately 0.026%) revealing differential expression. Of these 53 genes expressions were up-regulated, the most enhanced ones being human homolog of yeast IPP isomerase, human low density lipoprotein receptor gene, Squalene epoxidase gene, 7-dehydrocholesterol reductase, and 55 were down-regulated, the most decreased ones being heat shock 70 kD protein 1, TCB gene encoding cytosolic thyroid hormone-binding protein in HUVECs exposed to low shear stress. These results indicate that the cDNA microarray technique is effective in screening the differentially expressed genes in endothelial cells induced by various experimental conditions and the data may serve as stimuli to further researches.

Evaluation of the genetic alterations in direct and indirect exposures of hexavalent chromium [Cr(VI)] in leather tanning industry workers North Arcot District, South India.

PubMed

Balachandar, Vellingiri; Arun, Meyyazhagan; Mohana Devi, Subramaniam; Velmurugan, Palanivel; Manikantan, Pappusamy; Karthick Kumar, Alagamuthu; Sasikala, Keshavarao; Venkatesan, Chinnakulandai

2010-10-01

The focal aim of the present study was to identify the genetic alterations occurring in the tannery workers and surrounding inhabitants chronically exposed to hexavalent chromium [Cr(VI)]. A total of 108 samples which includes 72 exposed subjects [36 directly exposed (DE) subjects and 36 indirectly exposed (IE) subjects] and 36 controls were recruited for this study. The exposed subjects and controls were selected based on the Cr level present in air and their urine. Directly exposed subjects were categorized based on their work duration in the tannery industries, whereas the indirectly exposed subjects were categorized based on their year of residence in the place adjacent to tannery industries for more than 3 decades. Controls were normal and healthy. Age was matched for the exposed subjects and controls. The exposed subjects as well as the controls were categorized based on their age (group I, <40 years; group II, >41 years). Cell cultures were established from blood samples (5 ml from each subject) collected from the subjects (exposed subjects and controls) after obtaining informed consent. G-banding (Giemsa staining) of the cultures, micronucleus (MN) assay and comet assay were used to identify the genetic alterations of individuals exposed to Cr(VI) in comparison with the controls. A higher degree of total CA [12 ± 8.49 (21-25 years)] and MN [18.69 ± 7.39 (11-15 years)] was found in DE subjects compared to other groups. In IE subjects, elevated levels of CA [5.67 ± 1.15 (51-60 years)] and MN [25 ± 9.89 (71-80 years)] were observed. As expected, controls exhibited minimal number of alterations. The overall CA frequency due to Cr exposure was significantly different from that of the controls for both chromatid and chromosome type aberrations (P < 0.05 by ANOVA). The MN/1,000 binucleated cells were significantly increased (P < 0.05) in the peripheral lymphocytes of DE and IE subjects in comparison with controls. The mean tail length of comet assay for DE, IE and controls were analyzed. The mean tail length of DE subjects [4.21 (3.21-10.98)] was higher compared to that of IE subjects [3.98 (2.98-11.27)] and controls [3.01 (2.68-9.40)]. In conclusion, this work shows a clear genotoxic effect associated with chromium exposure, both directly and indirectly. Our result reinforces the higher sensitivity of cytogenetic assays for the biomonitoring of occupationally exposed populations. There is a strong need to educate those who work with potentially hazardous heavy about its adverse effects and highlight the importance of using protective measures.

Low CD4+ T-cell levels and B-cell apoptosis in vertically HIV-exposed noninfected children and adolescents.

PubMed

Miyamoto, Maristela; Pessoa, Silvana D; Ono, Erika; Machado, Daisy M; Salomão, Reinaldo; Succi, Regina C de M; Pahwa, Savita; de Moraes-Pinto, Maria Isabel

2010-12-01

Lymphocyte subsets, activation markers and apoptosis were assessed in 20 HIV-exposed noninfected (ENI) children born to HIV-infected women who were or not exposed to antiretroviral (ARV) drugs during pregnancy and early infancy. ENI children and adolescents were aged 6-18 years and they were compared to 25 age-matched healthy non-HIV-exposed children and adolescents (Control). ENI individuals presented lower CD4(+) T cells/mm(3) than Control group (control: 1120.3 vs. ENI: 876.3; t-test, p = 0.030). ENI individuals had higher B-cell apoptosis than Control group (Control: 36.6%, ARV exposed: 82.3%, ARV nonexposed: 68.5%; Kruskal-Wallis, p < 0.05), but no statistical difference was noticed between those exposed and not exposed to ARV. Immune activation in CD4(+) T, CD8(+) T and in B cells was comparable in ENI and in Control children and adolescents. Subtle long-term immune alterations might persist among ENI individuals, but the clinical consequences if any are unknown, and these children require continued monitoring.

Characteristics of Myeloid Differentiation and Maturation Pathway Derived from Human Hematopoietic Stem Cells Exposed to Different Linear Energy Transfer Radiation Types

PubMed Central

Monzen, Satoru; Yoshino, Hironori; Kasai-Eguchi, Kiyomi; Kashiwakura, Ikuo

2013-01-01

Exposure of hematopoietic stem/progenitor cells (HSPCs) to ionizing radiation causes a marked suppression of mature functional blood cell production in a linear energy transfer (LET)- and/or dose-dependent manner. However, little information about LET effects on the proliferation and differentiation of HSPCs has been reported. With the aim of characterizing the effects of different types of LET radiations on human myeloid hematopoiesis, in vitro hematopoiesis in Human CD34+ cells exposed to carbon-ion beams or X-rays was compared. Highly purified CD34+ cells exposed to each form of radiation were plated onto semi-solid culture for a myeloid progenitor assay. The surviving fractions of total myeloid progenitors, colony-forming cells (CFC), exposed to carbon-ion beams were significantly lower than of those exposed to X-rays, indicating that CFCs are more sensitive to carbon-ion beams (D 0 = 0.65) than to X-rays (D 0 = 1.07). Similar sensitivities were observed in granulocyte-macrophage and erythroid progenitors, respectively. However, the sensitivities of mixed-type progenitors to both radiation types were similar. In liquid culture for 14 days, no significant difference in total numbers of mononuclear cells was observed between non-irradiated control culture and cells exposed to 0.5 Gy X-rays, whereas 0.5 Gy carbon-ion beams suppressed cell proliferation to 4.9% of the control, a level similar to that for cells exposed to 1.5 Gy X-rays. Cell surface antigens associated with terminal maturation, such as CD13, CD14, and CD15, on harvest from the culture of X-ray-exposed cells were almost the same as those from the non-irradiated control culture. X-rays increased the CD235a+ erythroid-related fraction, whereas carbon-ion beams increased the CD34+CD38− primitive cell fraction and the CD13+CD14+/−CD15− fraction. These results suggest that carbon-ion beams inflict severe damage on the clonal growth of myeloid HSPCs, although the intensity of cell surface antigen expression by mature myeloid cells derived from HSPCs exposed to each type of radiation was similar to that by controls. PMID:23555027

A thiol probe for measuring unfolded protein load and proteostasis in cells.

PubMed

Chen, Moore Z; Moily, Nagaraj S; Bridgford, Jessica L; Wood, Rebecca J; Radwan, Mona; Smith, Trevor A; Song, Zhegang; Tang, Ben Zhong; Tilley, Leann; Xu, Xiaohong; Reid, Gavin E; Pouladi, Mahmoud A; Hong, Yuning; Hatters, Danny M

2017-09-07

When proteostasis becomes unbalanced, unfolded proteins can accumulate and aggregate. Here we report that the dye, tetraphenylethene maleimide (TPE-MI) can be used to measure cellular unfolded protein load. TPE-MI fluorescence is activated upon labelling free cysteine thiols, normally buried in the core of globular proteins that are exposed upon unfolding. Crucially TPE-MI does not become fluorescent when conjugated to soluble glutathione. We find that TPE-MI fluorescence is enhanced upon reaction with cellular proteomes under conditions promoting accumulation of unfolded proteins. TPE-MI reactivity can be used to track which proteins expose more cysteine residues under stress through proteomic analysis. We show that TPE-MI can report imbalances in proteostasis in induced pluripotent stem cell models of Huntington disease, as well as cells transfected with mutant Huntington exon 1 before the formation of visible aggregates. TPE-MI also detects protein damage following dihydroartemisinin treatment of the malaria parasites Plasmodium falciparum. TPE-MI therefore holds promise as a tool to probe proteostasis mechanisms in disease.Proteostasis is maintained through a number of molecular mechanisms, some of which function to protect the folded state of proteins. Here the authors demonstrate the use of TPE-MI in a fluorigenic dye assay for the quantitation of unfolded proteins that can be used to assess proteostasis on a cellular or proteome scale.

Cytokine profiles of HeLa and human diploid cells induced by different fractions of Vibrio parahaemolyticus cultures exposed to stress conditions.

PubMed

Chifiriuc, Mariana Carmen; Bleotu, Coralia; Pîrcălăbioru, Gratiela; Israil, Anca Michaela; Dinu, Sorin; Rută, Simona Maria; Grancea, Camelia; Lazăr, Veronica

2010-01-01

Vibrio (V.) parahaemolyticus is an aquatic halophilic bacteria which produces gastroenteritis and in rare cases septicaemia after the consumption of raw or under-cooked contaminated seafood.The severity of diarrheal illness caused by this bacterium is closely related to the presence of two types of hemolysins (the thermostable direct hemolysin-TDH and TDH related hemolysin-TRH) and also of type III secretion system (TTSS) proteins. The TTSS type 1 induces a wide array of effects on infected HeLa cells such as autophagy, oncosis, cell rounding and lysis. Previous studies have shown that heat shock proteins have the ability to stimulate the production of interleukins in different cellular cultures. In our studies we have stimulated two cellular lines (HeLa and human diploid cells) with different V. parahaemolyticus culture fractions in order to observe the effect on cytokines production. Thus, the purpose of this study was to analyze the expression of IL-1, IL-2, IL-4, IL-6, IL-10 and TNF-alpha induced by the cell treatment with total cellular lysate, periplasmic fractions and culture supernatants extracted from V. parahaemolyticus exposed to normal and also to stress conditions. The ELISA assay of the cytokine profile of the HeLa and HDC cell lines stimulated with different bacterial fractions revealed that in the V. parahemolyticus cultures submitted to osmotic and heat shock stress are accumulating factors (probably heat shock proteins) which are exhibiting immunomodulatory activity, responsible for the induction of a pro-inflammatory response associated with increased levels of IL-6 and TNF-alpha expression, however balanced by the stimulation of the anti-inflammatory cytokine IL-4 synthesis.

Exposure of a tendon extracellular matrix to synovial fluid triggers endogenous and engrafted cell death: A mechanism for failed healing of intrathecal tendon injuries.

PubMed

Garvican, Elaine R; Salavati, Mazdak; Smith, Roger K W; Dudhia, Jayesh

2017-09-01

The purpose of this study was to investigate the effect of normal synovial fluid (SF) on exposed endogenous tendon-derived cells (TDCs) and engrafted mesenchymal stem cells (MSCs) within the tendon extracellular matrix. Explants from equine superficial digital flexor (extra-synovial) and deep digital flexor tendons (DDFTs) from the compressed, intra-synovial and the tensile, extra-synovial regions were cultured in allogeneic or autologous SF-media. Human hamstring explants were cultured in allogeneic SF. Explant viability was assessed by staining. Proliferation of equine monolayer MSCs and TDCs in SF-media and co-culture with DDFT explants was determined by alamarblue®. Non-viable Native Tendon matrices (NNTs) were re-populated with MSCs or TDCs and cultured in SF-media. Immunohistochemical staining of tendon sections for the apoptotic proteins caspase-3, -8, and -9 was performed. Contact with autologous or allogeneic SF resulted in rapid death of resident tenocytes in equine and human tendon. SF did not affect the viability of equine epitenon cells, or of MSCs and TDCs in the monolayer or indirect explant co-culture. MSCs and TDCs, engrafted into NNTs, died when cultured in SF. Caspase-3, -8, and -9 expression was the greatest in SDFT explants exposed to allogeneic SF. The efficacy of cells administered intra-synovially for tendon lesion repair is likely to be limited, since once incorporated into the matrix, cells become vlnerable to the adverse effects of SF. These observations could account for the poor success rate of intra-synovial tendon healing following damage to the epitenon and contact with SF, common with most soft tissue intra-synovial pathologies.

Curcumin and Vitamin E Protect against Adverse Effects of Benzo[a]pyrene in Lung Epithelial Cells

PubMed Central

Cai, Qingsong; Lv, Tangfeng; Singh, Kamaleshwar; Gao, Weimin

2014-01-01

Benzo[a]pyrene (BaP), a well-known environmental carcinogen, promotes oxidative stress and DNA damage. Curcumin and vitamin E (VE) have potent antioxidative activity that protects cells from oxidative stress and cellular damage. The objectives of the present study were to investigate the adverse effects of BaP on normal human lung epithelial cells (BEAS-2B), the potential protective effects of curcumin and VE against BaP-induced cellular damage, and the molecular mechanisms of action. MTT assay, flow cytometry, fluorescence microplate assay, HPLC, qRT-PCR, and western blot were performed to analyze cytotoxicity, cell cycle, reactive oxygen species (ROS), BaP diol-epoxidation (BPDE)-DNA adducts, gene expression, and protein expression, respectively. Curcumin or VE prevented cells from BaP-induced cell cycle arrest and growth inhibition, significantly suppressed BaP-induced ROS levels, and decreased BPDE-DNA adducts. While CYP1A1 and 1B1 were induced by BaP, these inductions were not significantly reduced by curcumin or VE. Moreover, the level of activated p53 and PARP-1 were significantly induced by BaP, whereas this induction was markedly reduced after curcumin and VE co-treatment. Survivin was significantly down-regulated by BaP, and curcumin significantly restored survivin expression in BaP-exposed cells. The ratio of Bax/Bcl-2 was also significantly increased in cells exposed to BaP and this increase was reversed by VE co-treatment. Taken together, BaP-induced cytotoxicity occurs through DNA damage, cell cycle arrest, ROS production, modulation of metabolizing enzymes, and the expression/activation of p53, PARP-1, survivin, and Bax/Bcl-2. Curcumin and VE could reverse some of these BaP-mediated alterations and therefore be effective natural compounds against the adverse effects of BaP in lung cells. PMID:24664296

Hyaluronan in aged collagen matrix increases prostate epithelial cell proliferation

PubMed Central

Damodarasamy, Mamatha; Vernon, Robert B.; Chan, Christina K.; Plymate, Stephen R.; Wight, Thomas N.

2015-01-01

The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging. PMID:25124870

[Constricted ear therapy with free auricular composite grafts].

PubMed

Liu, Tun; Zhang, Lian-sheng; Zhuang, Hong-xing; Zhang, Ke-yuan

2004-03-01

A simple and effective therapy for single side constricted ear. Transplanting normal side free composite auricular grafts to constricted ear (15 patients and 15 sides), then lengthening the helix, exposing the scapha, correcting deformity. The 15 patients composite grafts all survived. The helix has been lengthened, the scapha exposed, the normal ear reduced, the constricted ear augmented and two sides ear have become symmetry. This method is simple and results are satisfied.

Pulmonary function abnormalities in never-smoking flight attendants exposed to secondhand tobacco smoke in the aircraft cabin.

PubMed

Arjomandi, Mehrdad; Haight, Thaddeus; Redberg, Rita; Gold, Warren M

2009-06-01

To determine whether the flight attendants who were exposed to secondhand tobacco smoke in the aircraft cabin have abnormal pulmonary function. We administered questionnaires and performed pulmonary function testing in 61 never-smoking female flight attendants who worked in active air crews before the smoking ban on commercial aircraft (preban). Although the preban flight attendants had normal FVC, FEV1, and FEV1/FVC ratio, they had significantly decreased flow at mid- and low-lung volumes, curvilinear flow-volume curves, and evidence of air trapping. Furthermore, the flight attendants had significantly decreased diffusing capacity (77.5% +/- 11.2% predicted normal) with 51% having a diffusing capacity below their 95% normal prediction limit. This cohort of healthy never-smoking flight attendants who were exposed to secondhand tobacco smoke in the aircraft cabin showed pulmonary function abnormalities suggestive of airway obstruction and impaired diffusion.

No neurochemical evidence of brain injury after blast overpressure by repeated explosions or firing heavy weapons.

PubMed

Blennow, K; Jonsson, M; Andreasen, N; Rosengren, L; Wallin, A; Hellström, P A; Zetterberg, H

2011-04-01

Psychiatric and neurological symptoms are common among soldiers exposed to blast without suffering a direct head injury. It is not known whether such symptoms are direct consequences of blast overpressure. To examine if repeated detonating explosions or firing if of heavy weapons is associated with neurochemical evidence of brain damage. Three controlled experimental studies. In the first, army officers were exposed to repeated firing of a FH77B howitzer or a bazooka. Cerebrospinal fluid (CSF) was taken post-exposure to measure biomarkers for brain damage. In the second, officers were exposed for up to 150 blasts by firing a bazooka, and in the third to 100 charges of detonating explosives of 180 dB. Serial serum samples were taken after exposure. Results were compared with a control group consisting of 19 unexposed age-matched healthy volunteers. The CSF biomarkers for neuronal/axonal damage (tau and neurofilament protein), glial cell injury (GFAP and S-100b), blood-brain barrier damage (CSF/serum albumin ratio) and hemorrhages (hemoglobin and bilirubin) and the serum GFAP and S-100b showed normal and stable levels in all exposed officers. Repeated exposure to high-impact blast does not result in any neurochemical evidence of brain damage. These findings are of importance for soldiers regularly exposed to high-impact blast when firing artillery shells or other types of heavy weapons. © 2010 John Wiley & Sons A/S.

Effects of AISI 316L corrosion products in in vitro bone formation.

PubMed

Morais, S; Sousa, J P; Fernandes, M H; Carvalho, G S; de Bruijn, J D; van Blitterswijk, C A

1998-06-01

Rat bone marrow cells were cultured in experimental conditions that favour the proliferation and differentiation of osteoblastic cells (i.e., 2.52 x 10(-4) mol l(-1) ascorbic acid, 10(-2) mol l(-1) beta-glycerophosphate and 10(-8) mol l(-1) dexamethasone) in the absence and in the presence of stainless-steel corrosion products, for a period of 18 days. An AISI 316L stainless-steel slurry (SS) was obtained by electrochemical means and the concentrations of the major metal ions, determined by atomic absorption spectrometry, were 8.78 x 10(-3) mol l(-1) of Fe, 4.31 x 10(-3) mol l(-1) of Cr and 2.56 x 10(-3) mol l(-1) of Ni. Bone marrow cells were exposed to 0.01, 0.1 and 1% of the SS and at the end of the incubation period, control and treated cultures were evaluated by histochemical assays for the identification of the presence of alkaline phosphatase and also calcium and phosphate deposition. Cultures were further observed by scanning electron microscopy. Levels of total and ionised calcium and phosphorus in the culture media collected from control and metal exposed cell cultures were also quantified. Histochemical staining showed that control cultures presented a strong reaction for the presence of alkaline phosphatase and exhibited formation of calcium and phosphates deposits. The presence of 0.01% SS caused no detectable biological effects in these cultures, 0.1% SS impaired osteoblastic behaviour and, 1% SS resulted in cell death. In the absence of bone cells, levels of total and ionised calcium and phosphorus in the control and metal added culture medium were similar throughout the incubation period. A significant decrease in the levels of ionised calcium and phosphorus were observed in the culture medium of control cultures and also in cultures exposed to 0.01% SS after two weeks of incubation, an event related with the formation of mineral calcium phosphate deposits in these cultures. In cultures grown in the presence of 0.1 and 1% SS corrosion products, levels of calcium and phosphorus were similar to those observed in the absence of cells. Results showed that stainless-steel corrosion products above certain concentrations may disturb the normal behaviour of osteoblast-like rat bone marrow cell cultures.

An efficient PEGylated liposomal nanocarrier containing cell-penetrating peptide and pH-sensitive hydrazone bond for enhancing tumor-targeted drug delivery.

PubMed

Ding, Yuan; Sun, Dan; Wang, Gui-Ling; Yang, Hong-Ge; Xu, Hai-Feng; Chen, Jian-Hua; Xie, Ying; Wang, Zhi-Qiang

2015-01-01

Cell-penetrating peptides (CPPs) as small molecular transporters with abilities of cell penetrating, internalization, and endosomal escape have potential prospect in drug delivery systems. However, a bottleneck hampering their application is the poor specificity for cells. By utilizing the function of hydration shell of polyethylene glycol (PEG) and acid sensitivity of hydrazone bond, we constructed a kind of CPP-modified pH-sensitive PEGylated liposomes (CPPL) to improve the selectivity of these peptides for tumor targeting. In CPPL, CPP was directly attached to liposome surfaces via coupling with stearate (STR) to avoid the hindrance of PEG as a linker on the penetrating efficiency of CPP. A PEG derivative by conjugating PEG with STR via acid-degradable hydrazone bond (PEG2000-Hz-STR, PHS) was synthesized. High-performance liquid chromatography and flow cytometry demonstrated that PHS was stable at normal neutral conditions and PEG could be completely cleaved from liposome surface to expose CPP under acidic environments in tumor. An optimal CPP density on liposomes was screened to guaranty a maximum targeting efficiency on tumor cells as well as not being captured by normal cells that consequently lead to a long circulation in blood. In vitro and in vivo studies indicated, in 4 mol% CPP of lipid modified system, that CPP exerted higher efficiency on internalizing the liposomes into targeted subcellular compartments while remaining inactive and free from opsonins at a maximum extent in systemic circulation. The 4% CPPL as a drug delivery system will have great potential in the clinical application of anticancer drugs in future.