Pb2+ Modulates Ca2+ Membrane Permeability In Paramecium

NASA Astrophysics Data System (ADS)

Bernal-Martínez, Juan; Ortega Soto, Arturo

2004-09-01

Intracellular recording experiments in current clamp configuration were done to evaluate whether Pb2+ modulates ionic membrane permeability in the fresh water Paramecium tetraurelia. It was found that Pb2+ triggers in a dose-dependent manner, a burst of spontaneous action potentials followed by a robust and sustained after hyper-polarization. In addition, Pb2+ increased the frequency of firing the spontaneous Ca2+-Action Potential and also, the duration of Ca2+-Action Potential, in a dose and reversibly-dependent manner. These results suggest that Pb2+ increases calcium membrane permeability of Paramecium and probably activates a calcium-dependent-potassium conductance in the ciliate.

Development of a Spring-Loaded Impact Device to Deliver Injurious Mechanical Impacts to the Articular Cartilage Surface

PubMed Central

Alexander, Peter G.; Song, Yingjie; Taboas, Juan M.; Chen, Faye H.; Melvin, Gary M.; Manner, Paul A.

2013-01-01

Objective: Traumatic impacts on the articular joint surface in vitro are known to lead to degeneration of the cartilage. The main objective of this study was to develop a spring-loaded impact device that can be used to deliver traumatic impacts of consistent magnitude and rate and to find whether impacts cause catabolic activities in articular cartilage consistent with other previously reported impact models and correlated with the development of osteoarthritic lesions. In developing the spring-loaded impactor, the operating hypothesis is that a single supraphysiologic impact to articular cartilage in vitro can affect cartilage integrity, cell viability, sulfated glycosaminoglycan and inflammatory mediator release in a dose-dependent manner. Design: Impacts of increasing force are delivered to adult bovine articular cartilage explants in confined compression. Impact parameters are correlated with tissue damage, cell viability, matrix and inflammatory mediator release, and gene expression 24 hours postimpact. Results: Nitric oxide release is first detected after 7.7 MPa impacts, whereas cell death, glycosaminoglycan release, and prostaglandin E2 release are first detected at 17 MPa. Catabolic markers increase linearly to maximal levels after ≥36 MPa impacts. Conclusions: A single supraphysiologic impact negatively affects cartilage integrity, cell viability, and GAG release in a dose-dependent manner. Our findings showed that 7 to 17 MPa impacts can induce cell death and catabolism without compromising the articular surface, whereas a 17 MPa impact is sufficient to induce increases in most common catabolic markers of osteoarthritic degeneration. PMID:26069650

Evidence for a possible neurotransmitter/neuromodulator role of tyramine on the locust oviducts.

PubMed

Donini, Andrew; Lange, Angela B

2004-04-01

Visualization of the tyraminergic innervation of the oviducts was demonstrated by immunohistochemistry, and the presence of tyramine was confirmed using high-performance liquid chromatography coupled to electrochemical detection. Oviducts incubated in high-potassium saline released tyramine in a calcium-dependent manner. Stimulation of the oviducal nerves also resulted in tyramine release, suggesting that tyramine might function as a neurotransmitter/neuromodulator at the locust oviducts. Tyramine decreased the basal tension, and also attenuated proctolin-induced contractions in a dose-dependent manner over a range of doses between 10(-7) and 10(-4) M. Low concentrations of tyramine attenuated forskolin-stimulated cyclic AMP levels in a dose-dependent manner. This effect was not blocked by yohimbine. High concentrations of tyramine increased basal cyclic AMP levels of locust oviducts in a dose-dependent manner; however, the increases in cyclic AMP were only evident at the highest concentrations tested, 5 x 10(-5) and 10(-4) M tyramine. The tyramine-induced increase in cyclic AMP shared a similar pharmacological profile with the octopamine-induced increase in cyclic AMP. Tyramine increased the amplitude of excitatory junction potentials at low concentrations while hyperpolarizing the membrane potential by 2-5 mV. A further increase in the amplitude of the excitatory junction potentials and the occurrence of an active response was seen upon washing tyramine from the preparation. These results suggest that tyramine can activate at least three different endogenous receptors on the locust oviducts a putative tyramine receptor at low concentrations, a different tyramine receptor to inhibit muscle contraction, and an octopamine receptor at high concentrations.

Effect of ammonium metavanadate on the murine immune response

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

Cohen, M.D.; Wei, C.I.; Tan, H.

1986-01-01

Female B/sub 6/C/sub 3/F/sub 1/ mice were exposed to ammonium metavanadate (NH/sub 4/VO/sub 3/) by intraperitoneal injection every 3 d at 2.5, 5.0, or 10 mg V/kg for 3, 6, or 9 w and were then assayed for alterations in immunoresponsiveness. Resistance to Escherichia coli endotoxin lethality increased in a dose-dependent manner up to 6 w of exposure, while resistance to viable gram-positive Listeria lethality was depressed in a dose-dependent manner. Comparison of LD20 values indicated a 250-fold decrease in resistance to Listeria at the lowest vanadium exposure and a 40% increase in resistance to endotoxin after the highest vanadiummore » exposure. Peritoneal macrophage phagocytic capacities were decreased in a dose-dependent manner, but viabilities remained unaffected. Rosetting capacity of splenic lymphocytes was increased following vanadium exposure. Liver and splenic enlargement was observed, and examination of splenic tissue indicated enhanced formation of megakaryocytes and red blood cell precursors. Subchronic exposure to vanadium may thus disrupt the normal function of the immune system.« less

Systemic SMAD7 Gene Therapy Increases Striated Muscle Mass and Enhances Exercise Capacity in a Dose-Dependent Manner.

PubMed

Maricelli, Joseph W; Bishaw, Yemeserach M; Wang, Bo; Du, Min; Rodgers, Buel D

2018-03-01

Striated muscle wasting occurs with a variety of disease indications, contributing to mortality and compromising life quality. Recent studies indicate that the recombinant adeno-associated virus (serotype 6) Smad7 gene therapeutic, AVGN7, enhances skeletal and cardiac muscle mass and prevents cancer-induced wasting of both tissues. This is accomplished by attenuating ActRIIb intracellular signaling and, as a result, the physiological actions of myostatin and other ActRIIb ligands. AVGN7 also enhances isolated skeletal muscle twitch force, but is unknown to improve systemic muscle function similarly, especially exercise capacity. A 2-month-long dose-escalation study was therefore conducted using 5 × 10 11 , 1 × 10 12 , and 5 × 10 12 vg/mouse and different tests of systemic muscle function. Body mass, skeletal muscle mass, heart mass, and forelimb grip strength were all increased in a dose-dependent manner, as was the fiber cross-sectional area of tibialis anterior muscles. Maximal oxygen consumption (VO 2 max), a measure of metabolic rate, was similarly enhanced during forced treadmill running, and although the total distance traveled was only elevated by the highest dose, all doses reduced the energy expenditure rate compared to control mice injected with an empty vector. Such improvements in VO 2 max are consistent with physiological cardiac hypertrophy, which is highly beneficial and a normal adaptive response to exercise. This was particularly evident at the lowest dose tested, which had minimal significant effects on skeletal muscle mass and/or function, but increased heart weight and exercise capacity. These results together suggest that AVGN7 enhances striated muscle mass and systemic muscle function. They also define minimally effective and optimal doses for future preclinical trials and toxicology studies and in turn will aid in establishing dose ranges for clinical trials.

New insight into mitochondrial changes in vascular endothelial cells irradiated by gamma ray.

PubMed

Hu, Shunying; Gao, Yajing; Zhou, Hao; Kong, Fanxuan; Xiao, Fengjun; Zhou, Pingkun; Chen, Yundai

2017-05-01

To investigate alterations of mitochondria in irradiated endothelial cells to further elucidate the mechanism underlying radiation-induced heart disease. Experiments were performed using human umbilical vein endothelial cells (HUVECs). HUVECs were irradiated with single gamma ray dose of 0, 5, 10 and 20 Gy, respectively. Apoptosis was assessed by flow cytometry at 24, 48 and 72 h post-irradiation, respectively. The intracellular reactive oxygen species (ROS) was measured with 2',7'-dichlorofluorescein-diacetate (DCFH-DA) at 24 h post-irradiation. Mitochondrial membrane potential (ΔΨm) by JC-1 and the opening of mitochondrial permeability transition pore (mPTP) by a calcein-cobalt quenching method were detected at 24 h post-irradiation in order to measure changes of mitochondria induced by gamma ray irradiation. Gamma ray irradiation increased HUVECs apoptosis in a dose-dependent and time-dependent manner. Irradiation also promoted ROS production in HUVECs in a dose-dependent manner. At 24 h post-irradiation, the results showed that irradiation decreases ΔΨm, however, paradoxically, flow cytometry showed green fluorescence instensity higher in irradiated HUVECs than in control HUVECs in an irradiation dose-dependent manner which indicated gamma ray irradiation inhibited mPTP opening in HUVECs. Gamma ray irradiation induces apoptosis and ROS production of endothelial cells, and decreases ΔΨm meanwhile contradictorily inhibiting the opening of mPTP.

Atomic force microscope-related study membrane-associated cytotoxicity in human pterygium fibroblasts induced by mitomycin C.

PubMed

Cai, Xiaofang; Yang, Xiaoxi; Cai, Jiye; Wu, Shixian; Chen, Qian

2010-03-25

Mitomycin C (MMC) has been shown to have a therapeutic effect against human pterygium fibroblasts (HPFs) by inducing apoptosis. However, there is little data about the effect of it on plasma membrane. In the present study, the cytotoxicity of MMC to HPFs including inhibiting cell growth, inducing apoptosis and bringing about membrane toxicity was investigated. It was found that MMC could significantly suppress the proliferation of HPFs in a dose-dependent manner by CCK-8 assay. Flow cytometric analysis also revealed that treatment with MMC resulted in increased percentages of apoptotic cells in a dose-dependent manner. Membrane lipid peroxidation level, lactate dehydrogenase (LDH) leakage, membrane surface topography, and membrane rigidity alterations were investigated to assess the membrane toxicity induced by MMC. Treatment with MMC at different concentrations accelerated membrane lipid peroxidation and potentiated LDH leakage, which was consistent with disturbance of membrane surface and decrease of membrane elasticity detected by atomic force microscopy. All the above changes led to the disturbed intracellular Ca(2+) homeostasis, which was an important signal triggering apoptosis. Hence, the membrane toxicity induced by MMC might play an important role in the process of apoptotic induction and the calcium channel may be one of the apoptosis mechanisms.

Effect of low dose and moderate dose gamma irradiation on the mechanical properties of bone and soft tissue allografts.

PubMed

Balsly, Colleen R; Cotter, Andrew T; Williams, Lisa A; Gaskins, Barton D; Moore, Mark A; Wolfinbarger, Lloyd

2008-12-01

The increased use of allograft tissue for musculoskeletal repair has brought more focus to the safety of allogenic tissue and the efficacy of various sterilization techniques. Gamma irradiation is an effective method for providing terminal sterilization to biological tissue, but it is also reported to have deleterious effects on tissue mechanics in a dose-dependent manner. At irradiation ranges up to 25 kGy, a clear relationship between mechanical strength and dose has yet to be established. The aim of this study was to investigate the mechanical properties of bone and soft tissue allografts, irradiated on dry ice at a low absorbed dose (18.3-21.8 kGy) and a moderate absorbed dose (24.0-28.5 kGy), using conventional compressive and tensile testing, respectively. Bone grafts consisted of Cloward dowels and iliac crest wedges, while soft tissue grafts consisted of patellar tendons, anterior tibialis tendons, semitendinosus tendons, and fascia lata. There were no statistical differences in mechanical strength or modulus of elasticity for any graft irradiated at a low absorbed dose, compared to control groups. Also, bone allografts and two soft tissue allografts (anterior tibialis and semitendinosus tendon) that were irradiated at a moderate dose demonstrated similar strength and modulus of elasticity values to control groups. The results of this study support the use of low dose and moderate dose gamma irradiation of bone grafts. For soft tissue grafts, the results support the use of low dose irradiation.

A spectrum of exercise training reduces soluble Aβ in a dose-dependent manner in a mouse model of Alzheimer's disease.

PubMed

Moore, Kaitlin M; Girens, Renee E; Larson, Sara K; Jones, Maria R; Restivo, Jessica L; Holtzman, David M; Cirrito, John R; Yuede, Carla M; Zimmerman, Scott D; Timson, Benjamin F

2016-01-01

Physical activity has long been hypothesized to influence the risk and pathology of Alzheimer's disease. However, the amount of physical activity necessary for these benefits is unclear. We examined the effects of three months of low and high intensity exercise training on soluble Aβ40 and Aβ42 levels in extracellular enriched fractions from the cortex and hippocampus of young Tg2576 mice. Low (LOW) and high (HI) intensity exercise training animals ran at speeds of 15m/min on a level treadmill and 32 m/min at a 10% grade, respectively for 60 min per day, five days per week, from three to six months of age. Sedentary mice (SED) were placed on a level, non-moving, treadmill for the same duration. Soleus muscle citrate synthase activity increased by 39% in the LOW group relative to SED, and by 71% in the HI group relative to LOW, indicating an exercise training effect in these mice. Soluble Aβ40 concentrations decreased significantly in an exercise training dose-dependent manner in the cortex. In the hippocampus, concentrations were decreased significantly in the HI group relative to LOW and SED. Soluble Aβ42 levels also decreased significantly in an exercise training dose-dependent manner in both the cortex and hippocampus. Five proteins involved in Aβ clearance (neprilysin, IDE, MMP9, LRP1 and HSP70) were elevated by exercise training with its intensity playing a role in each case. Our data demonstrate that exercise training reduces extracellular soluble Aβ in the brains of Tg2576 mice in a dose-dependent manner through an up-regulation of Aβ clearance. Copyright © 2015 Elsevier Inc. All rights reserved.

Antioxidant activities of saponins extracted from Radix Trichosanthis: an in vivo and in vitro evaluation

PubMed Central

2014-01-01

Background Radix Trichosanthis (RT), the dry root tuber of Trichosanthis kirilowii Maxim (Cucurbitaceae), is a traditional Chinese medicine. Although a wide range of saponin pharmacological properties has been identified, to our knowledge, this may be the first report to investigate the crude saponins from RT. The purpose of this study was to delineate the antioxidant activity both in vitro and in vivo by using ethyl acetate (EtOAc), n-butanol, and the mixture of n-butanol and EtOAc fractions. Methods In vitro antioxidant activity was detected by using DPPH free radical, hydrogen peroxide scavenging, and reducing power assays. After pretreatment with different fractions saponins at 2 mg/kg/d and 3 mg/kg/d of crude drug, respectively, an established CCl4 induced acute cytotoxicity model was used to evaluate the in vivo antioxidant potential by detection of superoxide dismutase (SOD), malonaldehyde (MDA), lactate dehydrogenase (LDH), and total antioxidant capacity (T-AOC) levels. Results The in vitro assay showed that the antioxidant activity of all the three fractions was promising. The reducing power of the EtOAc and the mixture of n-butanol and EtOAc extracts increased in a dose dependent manner. However, both the n-butanol and the mixture of n-butanol and EtOAc fractions in low dose exhibited in a time dependent manner with prolonged reaction time. As for hydrogen peroxide scavenging capability, the n-butanol fraction mainly demonstrated a time dependent manner, whereas EtOAc fraction showed a dose dependent manner. However, in case of in vivo assay, an increase of SOD and T-AOC and decrease of MDA and LDH levels were only observed in n-butanol (2 mg/kg/d of crude drug) extracts pretreatment group. Conclusions RT saponins in n-butanol fraction might be a potential antioxidant candidate, as CCl4-induced oxidative stress has been found to be alleviated, which may be associated with the time dependent manner of n-butanol saponins in a low dose. Further studies will be needed to investigate the active individual components in n-butanol extract, in vivo antioxidant activities and antioxidant mechanisms. PMID:24597831

Effect of ketamine dose on self-rated dissociation in patients with treatment refractory anxiety disorders.

PubMed

Castle, Cameron; Gray, Andrew; Neehoff, Shona; Glue, Paul

2017-10-01

Patients receiving ketamine for refractory depression and anxiety report dissociative symptoms in the first 60 min post-dose. The most commonly used instrument to assess this is the Clinician-Administered Dissociative States Scale (CADSS), developed based on the assessment of patients with dissociative symptoms. Its psychometric properties for ketamine-induced dissociation have not been reported. We evaluated these from a study using 0.25-1 mg/kg ketamine and midazolam (as an active control) in 18 patients with treatment-resistant anxiety. Dissociation ratings were increased by ketamine in a dose-dependent manner. In contrast, midazolam showed no effect on ratings of dissociation. For individual CADSS items, the magnitude of change and the ketamine dose at which changes were observed were not homogenous. The Cronbach alpha for the total scale was high (0.937), with acceptable item-rest correlations for almost all individual items. Purposefully removing items to maximise alpha did not lead to meaningful improvements. Acceptable internal consistency was still observed after removing items which lacked evidence of responsiveness at lower doses. The high Cronbach alpha values identified in this study suggests that the CADSS is an internally consistent instrument for evaluating ketamine-induced dissociation in clinical trials in anxiety, although it does not capture symptoms such as thought disorder.

Separation and characterization of polyphenolics from underutilized byproducts of fruit production (Choerospondias axillaris peels): inhibitory activity of proanthocyanidins against glycolysis enzymes.

PubMed

Li, Qian; Chen, Jun; Li, Ti; Liu, Chengmei; Zhai, Yuxin; McClements, David Julian; Liu, Jiyan

2015-12-01

Bioactive proanthocyanidins were isolated from the peel of Choerospondias axillaris fruit, which is a waste product of the food processing industry. Compositional analysis indicated that the proanthocyanidins had extension units mainly consisting of epicatechin gallate or epicatechin, and terminal units mainly consisting of catechin. Numerous polymeric forms of the molecules were detected, including monomers, dimers, and trimers. Certain fractions exhibited strong α-amylase or α-glucosidase inhibition in a dose-dependent manner. Furthermore, their inhibitory activities depended on their degree of polymerization and galloylation. For example, the most bioactive fraction had α-amylase and α-glucosidase inhibitory activities (IC50 values) of 541 and 3.1 μg mL(-1), respectively. This study demonstrates that proanthocyanidins from C. axillaris peels can inhibit carbohydrate digestive enzymes in vitro and may therefore serve as antidiabetic ingredients in functional or medical foods.

Immunostimulatory Activity of Opuntia ficus-indica var. Saboten Cladodes Fermented by Lactobacillus plantarum and Bacillus subtilis in RAW 264.7 Macrophages.

PubMed

Hwang, Joon-Ho; Lim, Sang-Bin

2017-02-01

To increase the functionality of Opuntia ficus-indica var. saboten cladodes, it was fermented by Lactobacillus plantarum and Bacillus subtilis. Eighty percent methanol extracts were investigated for their effects on nitric oxide (NO) production, cytokine secretion, nuclear factor-κB (NF-κB) activity, and mitogen-activated protein kinase (MAPK) phosphorylation in RAW 264.7 cells. Methanol extracts of L. plantarum culture medium (LPCME) and B. subtilis culture medium (BSCME) did not affect lipopolysaccharide (LPS)-induced NO production but, at 500 μg/mL, increased interferon (IFN)-γ-induced NO production by 55.2 and 66.5 μM, respectively, in RAW 264.7 cells. In RAW 264.7 cells not treated with LPS and IFN-γ, LPCME did not affect NO production, but BSCME increased NO production significantly in a dose-dependent manner. In addition, BSCME induced the expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in RAW 264.7 cells in a dose-dependent manner. BSCME at 500 μg/mL increased TNF-α and IL-1β mRNA levels by 83.8% and 82.2%, respectively. BSCME increased NF-κB-dependent luciferase activity in a dose-dependent manner; 500 μg/mL BSCME increased activity 9.1-fold compared with the control. BSCME induced the phosphorylation of p38, c-JUN NH 2 -terminal protein kinase (JNK), and extracellular signal-regulated kinase (ERK) in a dose-dependent manner, but did not affect total ERK levels. In conclusion, BSCME exerted immunostimulatory effects, which were mediated by MAPK phosphorylation and NF-κB activation, resulting in increased TNF-α and IL-1β gene expression in RAW 264.7 macrophages. Therefore, BSCM shows promise for use as an immunostimulatory therapeutic.

Genotoxicity of dill (Anethum graveolens L.), peppermint (Menthaxpiperita L.) and pine (Pinus sylvestris L.) essential oils in human lymphocytes and Drosophila melanogaster.

PubMed

Lazutka, J R; Mierauskiene, J; Slapsyte, G; Dedonyte, V

2001-05-01

Genotoxic properties of the essential oils extracted from dill (Anethum graveolens L.) herb and seeds, peppermint (Menthaxpiperita L.) herb and pine (Pinus sylvestris L.) needles were studied using chromosome aberration (CA) and sister chromatid exchange (SCE) tests in human lymphocytes in vitro, and Drosophila melanogaster somatic mutation and recombination test (SMART) in vivo. In the CA test, the most active essential oil was from dill seeds, then followed essential oils from dill herb, peppermint herb and pine needles, respectively. In the SCE test, the most active essential oils were from dill herb and seeds followed by essential oils from pine needles and peppermint herb. Essential oils from dill herb and seeds and pine needles induced CA and SCE in a clear dose-dependent manner, while peppermint essential oil induced SCE in a dose-independent manner. All essential oils were cytotoxic for human lymphocytes. In the SMART test, a dose-dependent increase in mutation frequency was observed for essential oils from pine and dill herb. Peppermint essential oil induced mutations in a dose-independent manner. Essential oil from dill seeds was almost inactive in the SMART test.

Prevalence of bisphosphonate-related osteonecrosis of the jaw-like lesions is increased in a chemotherapeutic dose-dependent manner in mice.

PubMed

Kuroshima, Shinichiro; Sasaki, Muneteru; Nakajima, Kazunori; Tamaki, Saki; Hayano, Hiroki; Sawase, Takashi

2018-07-01

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) worsens oral health-related quality of life. Most BRONJ occurs in multiple myeloma or metastatic breast cancer patients treated with bisphosphonate/chemotherapeutic combination therapies. Cyclophosphamide (CY), an alkylating chemotherapeutic drug, is used to treat multiple myeloma, although its use has been recently reduced. The aim of this study was to clarify the effects of CY dose on tooth extraction socket healing when CY is used with or without bisphosphonate in mice. Low-dose CY (50 mg/kg; CY-L), moderate-dose CY (100 mg/kg; CY-M), high-dose CY (150 mg/kg; CY-H), and bisphosphonate [Zometa (ZA): 0.05 mg/kg] were administered for 7 weeks. Each dose of CY and ZA in combination was also administered for 7 weeks. Both maxillary first molars were extracted at 3 weeks after the initiation of drug administration. Euthanasia was performed at 4 weeks post-extraction. Gross wound healing, microcomputed tomography analysis, histomorphometry, and immunohistochemistry were used to quantitatively evaluate osseous and soft tissue wound healing of tooth extraction sockets. ZA monotherapy induced no BRONJ-like lesions in mice. CY monotherapy rarely induced open wounds, though delayed osseous wound healing occurred in a CY dose-dependent manner. In contrast, CY/ZA combination therapy prevalently induced BRONJ-like lesions with compromised osseous and soft tissue healing in a CY dose-dependent manner. Interestingly, anti-angiogenesis was noted regardless of CY dose and ZA administration, even though only CY-M/ZA and CY-H/ZA combination therapies induced BRONJ-like lesions. Our findings suggest that high-dose CY may be associated with the development of BRONJ following tooth extraction only when CY is used together with ZA. In addition to anti-angiogenesis, other factors may contribute to the pathoetiology of BRONJ. Copyright © 2018 Elsevier Inc. All rights reserved.

Differential effects of antipsychotic and propsychotic drugs on prepulse inhibition and locomotor activity in Roman high- (RHA) and low-avoidance (RLA) rats

PubMed Central

Oliveras, Ignasi; Sánchez-González, Ana; Sampedro-Viana, Daniel; Piludu, Maria Antonietta; Río-Alamos, Cristóbal; Giorgi, Osvaldo; Corda, Maria G.; Aznar, Susana; González-Maeso, Javier; Gerbolés, Cristina; Blázquez, Gloria; Cañete, Toni; Tobeña, Adolf

2017-01-01

Rationale Animal models with predictive and construct validity are necessary for developing novel and efficient therapeutics for psychiatric disorders. Objectives We have carried out a pharmacological characterization of the Roman high-(RHA-I) and low-avoidance (RLA-I) rat strains with different acutely administered propsychotic (DOI, MK-801) and antipsychotic drugs (haloperidol, clozapine), as well as apomorphine, on prepulse inhibition (PPI) of startle and locomotor activity (activity cages). Results RHA-I rats display a consistent deficit of PPI compared with RLA-I rats. The typical antipsychotic haloperidol (dopamine D2 receptor antagonist) reversed the PPI deficit characteristic of RHA-I rats (in particular at 65 and 70 dB prepulse intensities) and reduced locomotion in both strains. The atypical antipsychotic clozapine (serotonin/dopamine receptor antagonist) did not affect PPI in either strain, but decreased locomotion in a dose-dependent manner in both rat strains. The mixed dopamine D1/D2 agonist, apomorphine, at the dose of 0.05 mg/kg, decreased PPI in RHA-I, but not RLA-I rats. The hallucinogen drug DOI (5-HT2A agonist; 0.1–1.0 mg/kg) disrupted PPI in RLA-I rats in a dose-dependent manner at the 70 dB prepulse intensity, while in RHA-Irats, only the 0.5 mg/kg dose impaired PPI at the 80 dB prepulse intensity. DOI slightly decreased locomotion in both strains. Finally, clozapine attenuated the PPI impairment induced by the NMDA receptor antagonist MK-801 only in RLA-I rats. Conclusions These results add experimental evidence to the view that RHA-I rats represent a model with predictive and construct validity of some dopamine and 5-HT2A receptor-related features of schizophrenia. PMID:28154892

Hedonic sensitivity to low-dose ketamine is modulated by gonadal hormones in a sex-dependent manner

PubMed Central

Saland, Samantha K.; Schoepfer, Kristin J.; Kabbaj, Mohamed

2016-01-01

We recently reported a greater sensitivity of female rats to rapid antidepressant-like effects of ketamine compared to male rats, and that ovarian-derived estradiol (E2) and progesterone (P4) are essential for this response. However, to what extent testosterone may also contribute, and whether duration of response to ketamine is modulated in a sex- and hormone-dependent manner remains unclear. To explore this, we systematically investigated the influence of testosterone, estradiol and progesterone on initiation and maintenance of hedonic response to low-dose ketamine (2.5 mg/kg) in intact and gonadectomized male and female rats. Ketamine induced a sustained increase in sucrose preference of female, but not male, rats in an E2P4-dependent manner. Whereas testosterone failed to alter male treatment response, concurrent administration of P4 alone in intact males enhanced hedonic response low-dose ketamine. Treatment responsiveness in female rats only was associated with greater hippocampal BDNF levels, but not activation of key downstream signaling effectors. We provide novel evidence supporting activational roles for ovarian-, but not testicular-, derived hormones in mediating hedonic sensitivity to low-dose ketamine in female and male rats, respectively. Organizational differences may, in part, account for the persistence of sex differences following gonadectomy and selective involvement of BDNF in treatment response. PMID:26888470

[Effects of sinensetin on proliferation and apoptosis of human gastric cancer AGS cells].

PubMed

Dong, Yang; Ji, Guang; Cao, Aili; Shi, Jianrong; Shi, Hailian; Xie, Jianqun; Wu, Dazheng

2011-03-01

To study the effects and mechanisms of sinensetin on proliferation and apoptosis of human AGS gastric cancer cells. MTT assay was used to detect the growth inhibition rates of human AGS gastric cancer cells treated with sinsesectin in different concentrations and times. The cell cycle distribution was measured by flow cytometry. The apoptosis was examined by Annexin-FITC/PI staining and DNA fragment analysis. The apoptosis morphology was observed by inverted fluorescence microscope after Hoechst 33342 staining. The protein expressions of p21 and p53 were detected by western blot. MTT assay showed that sinensetin inhibited the growth of AGS gastric cancer cells in a dose- and time-dependent manner. Sinensetin blocked AGS cells in G2/ M and increased the apoptosis rates of AGS cells in a dose-dependent manner. DNA ladder was observed in cells treated with 60 micromol x L(-1) sinensetin for 48 h. The typical apoptotic morphological changes including cell nucleus shrinkage, chromatin condensation and apoptotic bodies were observed when treated with different dose of sinensetin. Western blot showed that sinensetin increased expressions of p53 and p21 in a dose-dependent manner. Sinensetin could inhibit human AGS gastric cancer cells proliferation and induce cell cycle block in G2/M phase and apoptosis. The up regulation of p53 and p21 protein might be one of the mechanisms.

Necroptosis contributes to methamphetamine-induced cytotoxicity in rat cortical neurons.

PubMed

Xiong, Kun; Liao, Huidan; Long, Lingling; Ding, Yanjun; Huang, Jufang; Yan, Jie

2016-09-01

Necroptosis, a programmed necrosis, is involved in various types of neurodegenerative diseases. In this study, we investigated whether necroptosis contributed to neuronal damage in a methamphetamine injury model. Primary cultures of embryonic cortical neurons from Sprague-Dawley rats were subjected to different doses of methamphetamine with/without pre-treatment with a specific necroptosis inhibitor, Necrostatin-1. Necrosis was assessed by determining lactate dehydrogenase release and by Annexin V/propidium iodide double staining, while the neuronal ultra-structure was examined by electron microscopy. Tumor necrosis factor-α protein levels were determined by enzyme-linked immunosorbent assay. At early stages (12h) of post-treatment with methamphetamine, significant necrosis occurred and the viability of neurons decreased in a dose- and time-dependent manner in this model of acute neuronal injury. Pretreatment with Necrostatin-1 led to significant neuronal preservation compared with the methamphetamine-treated groups. Furthermore, tumor necrosis factor-α expression increased in a dose-dependent manner following methamphetamine exposure. Methamphetamine induced necrosis in rat cortical neurons in vitro, both time and dose dependently, and necroptosis may be an important newly identified mode of cortical neuronal death caused by single high-dose methamphetamine administration. Copyright © 2016 Elsevier B.V. All rights reserved.

Opposing roles for GABAA and GABAC receptors in short-term memory formation in young chicks.

PubMed

Gibbs, M E; Johnston, G A R

2005-01-01

The inhibitory neurotransmitter GABA has both inhibitory and enhancing effects on short-term memory for a bead discrimination task in the young chick. Low doses of GABA (1-3 pmol/hemisphere) injected into the multimodal association area of the chick forebrain, inhibit strongly reinforced memory, whereas higher doses (30-100 pmol/hemisphere) enhance weakly reinforced memory. The effect of both high and low doses of GABA is clearly on short-term memory in terms of both the time of injection and in the time that the memory loss occurs. We argue on the basis of relative sensitivities to GABA and to selective GABA receptor antagonists that low doses of GABA act at GABAC receptors (EC50 approximately 1 microM) and the higher doses of GABA act via GABAA receptors (EC50 approximately 10 microM). The selective GABAA receptor antagonist bicuculline inhibited strongly reinforced memory in a dose and time dependent manner, whereas the selective GABAC receptor antagonists TPMPA and P4MPA enhanced weakly reinforced in a dose and time dependent manner. Confirmation that different levels of GABA affect different receptor subtypes was demonstrated by the shift in the GABA dose-response curves to the selective antagonists. It is clear that GABA is involved in the control of short-term memory formation and its action, enhancing or inhibiting, depends on the level of GABA released at the time of learning.

Evaluation of Gamma Radiation-Induced Biochemical Changes in Skin for Dose Assesment: A Study on Small Experimental Animals.

PubMed

Kumar Soni, Sandeep; Basu, Mitra; Agrawal, Priyanka; Bhatnagar, Aseem; Chhillar, Neelam

2018-05-24

Researchers have been evaluating several approaches to assess acute radiation injury/toxicity markers owing to radiation exposure. Keeping in mind this background, we assumed that whole-body irradiation in single fraction in graded doses can affect the antioxidant profile in skin that could be used as an acute radiation injury/toxicity marker. Sprague-Dawley rats were treated with CO-60 gamma radiation (dose: 1-5 Gy; dose rate: 0.85 Gy/minute). Skin samples were collected (before and after radiation up to 72 hours) and analyzed for glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and lipid peroxidation (LPx). Intra-group comparison showed significant differences in GSH, GPx, SOD, and CAT, and they declined in a dose-dependent manner from 1 to 5 Gy (P value0.05). This study suggests that skin antioxidants were sensitive toward radiation even at a low radiation dose, which can be used as a predictor of radiation injury and altered in a dose-dependent manner. These biochemical parameters may have wider application in the evaluation of radiation-induced skin injury and dose assessment. (Disaster Med Public Health Preparedness. 2018;page 1 of 6).

Anti-inflammatory activity of 6-hydroxy-2,7-dimethoxy-1,4-henanthraquinone from tuberous roots of yam (Dioscorea batatas) through inhibition of prostaglandin D₂ and leukotriene C₄ production in mouse bone marrow-derived mast cells.

PubMed

Jin, Meihua; Lu, Yue; Yang, Ju Hye; Jo, Tae Hyung; Park, Young In; Lee, Chong-Kil; Park, Sang-Jo; Son, Kun Ho; Chang, Hyeun Wook

2011-09-01

6-Hydroxy-2,7-dimethoxy-1,4-phenanthraquinone (PAQ) isolated from the tuberous roots of Yam (Dioscorea batatas) inhibited cyclooxygenase-2 (COX-2) and cyclooxygenase-1 (COX-1) dependent prostaglandin D(2) (PGD(2)) generation in mouse bone marrow-derived mast cells in a concentration-dependent manner with IC(50) values of 0.08 μM and 0.27 μM, respectively. In the Western blotting with specific anti-COX-2 antibodies, the decrease of the quantity of PGD(2) was accompanied by a decrease in the COX-2 protein level. But PAQ did not affect COX-1 protein level. In addition, this compound inhibited 5-lipoxygenase (5-LOX) dependent production of leukotriene C(4) in a dose-dependent manner, with an IC(50) of 0.032 μM. These results demonstrate that PAQ has a dual COX-2/5-LOX inhibitory activity. This compound also inhibited the degranulation reaction in a dose-dependent manner with an IC(50) of 2.7 μM. Thus, these results suggest that PAQ may be useful in regulating mast cell-mediated inflammatory diseases.

Fluoxetine exposure impacts boldness in female Siamese fighting fish, Betta splendens.

PubMed

Dzieweczynski, Teresa L; Kane, Jessica L; Campbell, Brennah A; Lavin, Lindsey E

2016-01-01

The present study examined the effects of the selective serotonin reuptake inhibitor, fluoxetine, on the behavior of female Siamese fighting fish, Betta splendens, in three different boldness assays (Empty Tank, Novel Environment, Social Tendency). When females were unexposed to fluoxetine, boldness was consistent within a context and correlated across assays. Fluoxetine exposure affected behavior within and among individuals on multiple levels. Exposure reduced overall boldness levels, made females behave in a less consistent manner, and significantly reduced correlations over time and across contexts. Fluoxetine exerted its effects on female Betta splendens behavior in a dose-dependent fashion and these effects persisted even after females were housed in clean water. If fluoxetine exposure impacts behaviors such as exploration that are necessary to an individual’s success, this may yield evolutionary consequences. In conclusion, the results show that fluoxetine exposure alters behavior beyond the level of overall response and highlights the importance of studying the behavioral effects of inadvertent pharmaceutical exposure in multiple contexts and with different dosing regimes.

Transient impairment of hippocampus-dependent learning and memory in relatively low-dose of acute radiation syndrome is associated with inhibition of hippocampal neurogenesis.

PubMed

Kim, Joong-Sun; Lee, Hae-June; Kim, Jong Choon; Kang, Seong Soo; Bae, Chun-Sik; Shin, Taekyun; Jin, Jae-Kwang; Kim, Sung Ho; Wang, Hongbing; Moon, Changjong

2008-09-01

Neurogenesis in the adult hippocampus, which occurs constitutively, is vulnerable to ionizing radiation. In the relatively low-dose exposure of acute radiation syndrome (ARS), the change in the adult hippocampal function is poorly understood. This study analyzed the changes in apoptotic cell death and neurogenesis in the DGs of hippocampi from adult ICR mice with single whole-body gamma-irradiation using the TUNEL method and immunohistochemical markers of neurogenesis, Ki-67 and doublecortin (DCX). In addition, the hippocampus-dependent learning and memory tasks after single whole-body gamma-irradiation were examined in order to evaluate the hippocampus-related behavioral dysfunction in the relatively low-dose exposure of ARS. The number of TUNEL-positive apoptotic nuclei in the dentate gyrus (DG) was increased 6-12 h after acute gamma-irradiation (a single dose of 0.5 to 4 Gy). In contrast, the number of Ki-67- and DCX-positive cells began to decrease significantly 6 h postirradiation, reaching its lowest level 24 h after irradiation. The level of Ki-67 and DCX immunoreactivity decreased in a dose-dependent manner within the range of irradiation applied (0-4 Gy). In passive avoidance and object recognition memory test, the mice trained 1 day after acute irradiation (2 Gy) showed significant memory deficits, compared with the sham controls. In conclusion, the pattern of the hippocampus-dependent memory dysfunction is consistent with the change in neurogenesis after acute irradiation. It is suggested that a relatively low dose of ARS in adult ICR mice is sufficiently detrimental to interrupt the functioning of the hippocampus, including learning and memory, possibly through the inhibition of neurogenesis.

Indoor visible mold and mold odor are associated with new-onset childhood wheeze in a dose-dependent manner.

PubMed

Shorter, Caroline; Crane, Julian; Pierse, Nevil; Barnes, Phillipa; Kang, Janice; Wickens, Kristin; Douwes, Jeroen; Stanley, Thorsten; Täubel, Martin; Hyvärinen, Anne; Howden-Chapman, Philippa

2018-01-01

Evidence is accumulating that indoor dampness and mold are associated with the development of asthma. The underlying mechanisms remain unknown. New Zealand has high rates of both asthma and indoor mold and is ideally placed to investigate this. We conducted an incident case-control study involving 150 children with new-onset wheeze, aged between 1 and 7 years, each matched to two control children with no history of wheezing. Each participant's home was assessed for moisture damage, condensation, and mold growth by researchers, an independent building assessor and parents. Repeated measures of temperature and humidity were made, and electrostatic dust cloths were used to collect airborne microbes. Cloths were analyzed using qPCR. Children were skin prick tested for aeroallergens to establish atopy. Strong positive associations were found between observations of visible mold and new-onset wheezing in children (adjusted odds ratios ranged between 1.30 and 3.56; P ≤ .05). Visible mold and mold odor were consistently associated with new-onset wheezing in a dose-dependent manner. Measurements of qPCR microbial levels, temperature, and humidity were not associated with new-onset wheezing. The association between mold and new-onset wheeze was not modified by atopic status, suggesting a non-allergic association. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Chestnut astringent skin extract, an alpha-amylase inhibitor, retards carbohydrate absorption in rats and humans.

PubMed

Tsujita, Takahiro; Takaku, Takeshi; Suzuki, Tsuneo

2008-02-01

Inhibitors of carbohydrate-hydrolyzing enzyme play an important role to control postprandial blood glucose levels. In this paper, we investigated the effect of an ethanol extract from chestnut astringent skin (CAS) on alpha-amylase. Chestnut astringent skin extract strongly inhibited human and porcine pancreatic alpha-amylase. We also investigated the effect of CAS extract on carbohydrate absorption in rats and humans. Oral administration of CAS extract to normal rats fed corn starch (2 g/kg body weight), significantly suppressed the increase of blood glucose levels after starch loading in a dose-dependent manner. The effective dose of CAS extract required to achieve 20 and 40% suppression of the rise in blood glucose level was estimated to be 40 and 155 mg/kg body weight, respectively. Chestnut astringent skin extract also suppressed the rise in plasma insulin level and the fall in plasma non-esterified fatty acid level. In the type 2 diabetic rat model, CAS extract significantly suppressed the rise in blood glucose level after starch loading in a dose-dependent manner. Chestnut astringent skin extract also suppressed the rise in plasma glucose level after boiled rice loading in a dose-dependent manner in humans. The amount of CAS extract required to achieve 11 and 23% suppression in the rise in plasma glucose level was 300 and 600 mg/person, respectively. These results suggest that CAS extract retards absorption of carbohydrate and reduces post-prandial hyperglycemia.

Reduction of spermatogenesis in mice after tributyltin administration.

PubMed

Chen, Yufang; Zuo, Zhenghong; Chen, Shuzhen; Yan, Feihuang; Chen, Yixin; Yang, Zengming; Wang, Chonggang

2008-09-29

Organotin compounds, such as tributyltin (TBT) used as an antifouling biocide, can induce masculinization in female mollusks. However, few studies addressing the effect of TBT on spermatogenesis in mammalian have been reported. This study was conducted to investigate the effects of TBT at low doses (0.5, 5, and 50 microg/kg, respectively) on spermatogenesis in mice as exposed from puberty and gave insight into the mechanism. After exposure for 30 days, the gonadosomatic index (GSI) was significantly decreased. The testosterone levels in the testes were not altered and the 17beta-estradiol levels were significantly decreased in a dose-dependent manner, spermatogenesis of the testis was significantly inhibited. Estrogen receptor (ER-alpha and ER-beta) levels in testes of the mice exposed to TBT were decreased in a dose-dependent manner. The results suggest that ER play an important role in TBT-mediated inhibition of spermatogenesis.

DIMETHYLARSINIC ACID ALTERS EXPRESSION OF OXIDATIVE STRESS AND DNA REPAIR GENES IN A DOSE DEPENDENT MANNER IN THE TRANSITIONAL EPITHELIUM OF THE URINARY BLADDER FROM FEMALE F344 RATS.

EPA Science Inventory

Dose-dependent alteration of oxidative stress and DNA repair gene expression by Dimethylarsinic acid [DMA(V)] in transitional epithelium of urinary bladder from female F344 rats.
Arsenic (As) is a major concern as millions of people are at risk from drinking arsenic contaminat...

A Fully Automated High-Throughput Zebrafish Behavioral Ototoxicity Assay.

PubMed

Todd, Douglas W; Philip, Rohit C; Niihori, Maki; Ringle, Ryan A; Coyle, Kelsey R; Zehri, Sobia F; Zabala, Leanne; Mudery, Jordan A; Francis, Ross H; Rodriguez, Jeffrey J; Jacob, Abraham

2017-08-01

Zebrafish animal models lend themselves to behavioral assays that can facilitate rapid screening of ototoxic, otoprotective, and otoregenerative drugs. Structurally similar to human inner ear hair cells, the mechanosensory hair cells on their lateral line allow the zebrafish to sense water flow and orient head-to-current in a behavior called rheotaxis. This rheotaxis behavior deteriorates in a dose-dependent manner with increased exposure to the ototoxin cisplatin, thereby establishing itself as an excellent biomarker for anatomic damage to lateral line hair cells. Building on work by our group and others, we have built a new, fully automated high-throughput behavioral assay system that uses automated image analysis techniques to quantify rheotaxis behavior. This novel system consists of a custom-designed swimming apparatus and imaging system consisting of network-controlled Raspberry Pi microcomputers capturing infrared video. Automated analysis techniques detect individual zebrafish, compute their orientation, and quantify the rheotaxis behavior of a zebrafish test population, producing a powerful, high-throughput behavioral assay. Using our fully automated biological assay to test a standardized ototoxic dose of cisplatin against varying doses of compounds that protect or regenerate hair cells may facilitate rapid translation of candidate drugs into preclinical mammalian models of hearing loss.

Exposure-dependent incorporation of trifluridine into DNA of tumors and white blood cells in tumor-bearing mouse.

PubMed

Yamashita, Fumiaki; Komoto, Ikumi; Oka, Hiroaki; Kuwata, Keizo; Takeuchi, Mayuko; Nakagawa, Fumio; Yoshisue, Kunihiro; Chiba, Masato

2015-08-01

Trifluridine (TFT) is an antitumor component of a novel nucleoside antitumor agent, TAS-102, which consists of TFT and tipiracil hydrochloride (thymidine phosphorylase inhibitor). Incorporation of TFT into DNA is a probable mechanism of antitumor activity and hematological toxicity. The objective of this study was to examine the TFT incorporation into tumor- and white blood cell-DNA, and to elucidate the mechanism of TFT-related effect and toxicity. TFT effect on the colony formation of mouse bone marrow cells was also investigated. Pharmacokinetics of TFT was determined in nude mice after single oral administration of TAS-102, while the antitumor activity and body weight change were evaluated in the tumor-bearing nude mice after multiple oral administrations for 2 weeks. TFT concentrations in the blood- and tumor-DNA were determined by LC/MS/MS. The colony formation was evaluated by CFU-GM assay. TFT systemic exposure in plasma increased dose-dependently. The tumor growth rate and body weight gain decreased dose-dependently, but TFT concentrations in the DNA of tumor tissues and white blood cells increased dose-dependently. TFT inhibited colony formation of bone marrow cells in a concentration-dependent manner. A significant relationship between systemic exposure of TFT and pharmacological effects including the antitumor activity and body weight change was well explained by the TFT incorporation into DNA. TFT inhibited proliferations of mouse bone marrow cells and human colorectal carcinoma cells implanted to nude mice dose-dependently. The highest tolerable TFT exposure provides the highest antitumor activity, and the hematological toxicity may serve as a potential surrogate indicator of TAS-102 efficacy.

Mitigation of paracetamol-induced reproductive damage by chrysin in male rats via reducing oxidative stress.

PubMed

Aksu, E H; Özkaraca, M; Kandemir, F M; Ömür, A D; Eldutar, E; Küçükler, S; Çomaklı, S

2016-12-01

Paracetamol (PRC) is a nonsteroidal anti-inflammatory drug used widely as a painkiller for various diseases and as the symptomatic flu cure in several countries worldwide. PRC toxicity may occur under conditions of the overdose usage. Chrysin (CR) is a flavonoid that is naturally present in several plants, honey and propolis. The aim of this study was to investigate the effects of CR (at the doses of 25 mg kg -1 and 50 mg kg -1 ) pre-treatment over seven consecutive days against PRC-induced reproductive toxicity in male rats. Our results showed that PRC toxicity decreased the sperm motility, and increased dead sperm rate, abnormal sperm cell rate, apoptosis and MDA levels in testicular tissues. Pre-treatment with CR at the dose of 25 and 50 mg kg -1 for 7 days mitigated side effects of acute PRC toxicity in male reproductive system proportionally in a dose-dependent manner. This possible protection mechanism might be dependent on the antioxidant activity of CR. In conclusion, pre-treatment with CR at the dose of 25 and 50 mg kg -1 for 7 days can be the beneficial against PRC-induced reproductive toxicity proportionally in a dose-dependent manner. © 2016 Blackwell Verlag GmbH.

Safety, tolerability, and cerebrospinal fluid penetration of ursodeoxycholic Acid in patients with amyotrophic lateral sclerosis.

PubMed

Parry, Gareth J; Rodrigues, Cecilia M P; Aranha, Marcia M; Hilbert, Sarah J; Davey, Cynthia; Kelkar, Praful; Low, Walter C; Steer, Clifford J

2010-01-01

Amyotrophic lateral sclerosis is a progressive degenerative disease, which typically leads to death in 3 to 5 years. Neuronal cell death offers a potential target for therapeutic intervention. Ursodeoxycholic acid is a cytoprotective, endogenous bile acid that has been shown to be neuroprotective in experimental Huntington and Alzheimer diseases, retinal degeneration, and ischemic and hemorrhagic stroke. The objective of this research was to study the safety and the tolerability of ursodeoxycholic acid in amyotrophic lateral sclerosis and document effective and dose-dependent cerebrospinal fluid penetration. Eighteen patients were randomly assigned to receive ursodeoxycholic acid at doses of 15, 30, and 50 mg/kg of body weight per day. Serum and cerebrospinal fluid were obtained for analysis after 4 weeks of treatment. Treatment-emergent clinical and laboratory events were monitored weekly. Our data indicated that ursodeoxycholic acid is well tolerated by all subjects at all doses. We also showed that ursodeoxycholic acid is well absorbed after oral administration and crosses the blood-brain barrier in a dose-dependent manner. These results show excellent safety and tolerability of ursodeoxycholic acid. The drug penetrates the cerebrospinal fluid in a dose-dependent manner. A large, placebo-controlled clinical trial is needed to assess the efficacy of ursodeoxycholic acid in treating amyotrophic lateral sclerosis.

A highly infective plant-associated bacterium influences reproductive rates in pea aphids

PubMed Central

Hendry, Tory A.; Clark, Kelley J.; Baltrus, David A.

2016-01-01

Pea aphids, Acyrthosiphon pisum, have the potential to increase reproduction as a defence against pathogens, though how frequently this occurs or how infection with live pathogens influences this response is not well understood. Here we determine the minimum infective dose of an environmentally common bacterium and possible aphid pathogen, Pseudomonas syringae, to determine the likelihood of pathogenic effects to pea aphids. Additionally, we used P. syringae infection to investigate how live pathogens may alter reproductive rates. We found that oral bacterial exposure decreased subsequent survival of aphids in a dose-dependent manner and we estimate that ingestion of less than 10 bacterial cells is sufficient to increase aphid mortality. Pathogen dose was positively related to aphid reproduction. Aphids exposed to low bacterial doses showed decreased, although statistically indistinguishable, fecundity compared to controls. Aphids exposed to high doses reproduced significantly more than low dose treatments and also more, but not significantly so, than controls. These results are consistent with previous studies suggesting that pea aphids may use fecundity compensation as a response to pathogens. Consequently, even low levels of exposure to a common plant-associated bacterium may therefore have significant effects on pea aphid survival and reproduction. PMID:26998321

A highly infective plant-associated bacterium influences reproductive rates in pea aphids.

PubMed

Hendry, Tory A; Clark, Kelley J; Baltrus, David A

2016-02-01

Pea aphids, Acyrthosiphon pisum, have the potential to increase reproduction as a defence against pathogens, though how frequently this occurs or how infection with live pathogens influences this response is not well understood. Here we determine the minimum infective dose of an environmentally common bacterium and possible aphid pathogen, Pseudomonas syringae, to determine the likelihood of pathogenic effects to pea aphids. Additionally, we used P. syringae infection to investigate how live pathogens may alter reproductive rates. We found that oral bacterial exposure decreased subsequent survival of aphids in a dose-dependent manner and we estimate that ingestion of less than 10 bacterial cells is sufficient to increase aphid mortality. Pathogen dose was positively related to aphid reproduction. Aphids exposed to low bacterial doses showed decreased, although statistically indistinguishable, fecundity compared to controls. Aphids exposed to high doses reproduced significantly more than low dose treatments and also more, but not significantly so, than controls. These results are consistent with previous studies suggesting that pea aphids may use fecundity compensation as a response to pathogens. Consequently, even low levels of exposure to a common plant-associated bacterium may therefore have significant effects on pea aphid survival and reproduction.

Hydrostatic Compress Force Enhances the Viability and Decreases the Apoptosis of Condylar Chondrocytes through Integrin-FAK-ERK/PI3K Pathway.

PubMed

Ma, Dandan; Kou, Xiaoxing; Jin, Jing; Xu, Taotao; Wu, Mengjie; Deng, Liquan; Fu, Lusi; Liu, Yi; Wu, Gang; Lu, Haiping

2016-11-07

Reduced mechanical stimuli in many pathological cases, such as hemimastication and limited masticatory movements, can significantly affect the metabolic activity of mandibular condylar chondrocytes and the growth of mandibles. However, the molecular mechanisms for these phenomena remain unclear. In this study, we hypothesized that integrin-focal adhesion kinase (FAK)-ERK (extracellular signal-regulated kinase)/PI3K (phosphatidylinositol-3-kinase) signaling pathway mediated the cellular response of condylar chondrocytes to mechanical loading. Primary condylar chondrocytes were exposed to hydrostatic compressive forces (HCFs) of different magnitudes (0, 50, 100, 150, 200, and 250 kPa) for 2 h. We measured the viability, morphology, and apoptosis of the chondrocytes with different treatments as well as the gene, protein expression, and phosphorylation of mechanosensitivity-related molecules, such as integrin α2, integrin α5, integrin β1, FAK, ERK, and PI3K. HCFs could significantly increase the viability and surface area of condylar chondrocytes and decrease their apoptosis in a dose-dependent manner. HCF of 250 kPa resulted in a 1.51 ± 0.02-fold increase of cell viability and reduced the ratio of apoptotic cells from 18.10% ± 0.56% to 7.30% ± 1.43%. HCFs could significantly enhance the mRNA and protein expression of integrin α2, integrin α5, and integrin β1 in a dose-dependent manner, but not ERK1, ERK2, or PI3K. Instead, HCF could significantly increase phosphorylation levels of FAK, ERK1/2, and PI3K in a dose-dependent manner. Cilengitide, the potent integrin inhibitor, could dose-dependently block such effects of HCFs. HCFs enhances the viability and decreases the apoptosis of condylar chondrocytes through the integrin-FAK-ERK/PI3K pathway.

Hydrostatic Compress Force Enhances the Viability and Decreases the Apoptosis of Condylar Chondrocytes through Integrin-FAK-ERK/PI3K Pathway

PubMed Central

Ma, Dandan; Kou, Xiaoxing; Jin, Jing; Xu, Taotao; Wu, Mengjie; Deng, Liquan; Fu, Lusi; Liu, Yi; Wu, Gang; Lu, Haiping

2016-01-01

Reduced mechanical stimuli in many pathological cases, such as hemimastication and limited masticatory movements, can significantly affect the metabolic activity of mandibular condylar chondrocytes and the growth of mandibles. However, the molecular mechanisms for these phenomena remain unclear. In this study, we hypothesized that integrin-focal adhesion kinase (FAK)-ERK (extracellular signal–regulated kinase)/PI3K (phosphatidylinositol-3-kinase) signaling pathway mediated the cellular response of condylar chondrocytes to mechanical loading. Primary condylar chondrocytes were exposed to hydrostatic compressive forces (HCFs) of different magnitudes (0, 50, 100, 150, 200, and 250 kPa) for 2 h. We measured the viability, morphology, and apoptosis of the chondrocytes with different treatments as well as the gene, protein expression, and phosphorylation of mechanosensitivity-related molecules, such as integrin α2, integrin α5, integrin β1, FAK, ERK, and PI3K. HCFs could significantly increase the viability and surface area of condylar chondrocytes and decrease their apoptosis in a dose-dependent manner. HCF of 250 kPa resulted in a 1.51 ± 0.02-fold increase of cell viability and reduced the ratio of apoptotic cells from 18.10% ± 0.56% to 7.30% ± 1.43%. HCFs could significantly enhance the mRNA and protein expression of integrin α2, integrin α5, and integrin β1 in a dose-dependent manner, but not ERK1, ERK2, or PI3K. Instead, HCF could significantly increase phosphorylation levels of FAK, ERK1/2, and PI3K in a dose-dependent manner. Cilengitide, the potent integrin inhibitor, could dose-dependently block such effects of HCFs. HCFs enhances the viability and decreases the apoptosis of condylar chondrocytes through the integrin-FAK-ERK/PI3K pathway. PMID:27827993

Aluminium oxide nanoparticles induced morphological changes, cytotoxicity and oxidative stress in Chinook salmon (CHSE-214) cells.

PubMed

Srikanth, Koigoora; Mahajan, Amit; Pereira, Eduarda; Duarte, Armando Costa; Venkateswara Rao, Janapala

2015-10-01

Aluminium oxide nanoparticles (Al2 O3 NPs) are increasingly used in diverse applications that has raised concern about their safety. Recent studies suggested that Al2 O3 NPs induced oxidative stress may be the cause of toxicity in algae, Ceriodaphnia dubia, Caenorhabditis elegans and Danio rerio. However, there is paucity on the toxicity of Al2 O3 NPs on fish cell lines. The current study was aimed to investigate Al2 O3 NPs induced cytotoxicity, oxidative stress and morphological abnormality of Chinnok salmon cells (CHSE-214). A dose-dependent decline in cell viability was observed in CHSE-214 cells exposed to Al2 O3 NPs. Oxidative stress induced by Al2 O3 NPs in CHSE-214 cells has resulted in the significant reduction of superoxide dismutase, catalase and glutathione in a dose-dependent manner. However, a significant increase in glutathione sulfo-transferase and lipid peroxidation was observed in CHSE-214 cells exposed to Al2 O3 NPs in a dose-dependent manner. Significant morphological changes in CHSE-214 cells were observed when exposed to Al2 O3 NPs at 6, 12 and 24 h. The cells started to detach and appear spherical at 6 h followed by loss of cellular contents resulting in the shrinking of the cells. At 24 h, the cells started to disintegrate and resulted in cell death. Our data demonstrate that Al2 O3 NPs induce cytotoxicity and oxidative stress in a dose-dependent manner in CHSE-214 cells. Thus, our current work may serve as a base-line study for future evaluation of toxicity studies using CHSE-214 cells. Copyright © 2015 John Wiley & Sons, Ltd.

Anti-inflammatory and PPAR transactivational properties of flavonoids from the roots of Sophora flavescens.

PubMed

Quang, Tran Hong; Ngan, Nguyen Thi Thanh; Minh, Chau Van; Kiem, Phan Van; Tai, Bui Huu; Nhiem, Nguyen Xuan; Thao, Nguyen Phuong; Luyen, Bui Thi Thuy; Yang, Seo Young; Kim, Young Ho

2013-09-01

Anti-inflammatory and peroxisome proliferator-activated receptors (PPARs) transactivational effects of nine compounds (1 - 9) from the roots of Sophora flavescens were evaluated using NF-κB-luciferase, reverse transcriptase polymerase chain reaction, peroxisome proliferator response element (PPRE)-luciferase, and GAL-4-PPAR chimera assays. Compounds 4 and 8 significantly inhibited TNFα-induced NF-κB transcriptional activity in HepG2 cells in a dose-dependent manner, with IC₅₀ values of 4.0 and 4.4 μM, respectively. Furthermore, the transcriptional inhibitory function of these compounds was confirmed by a decrease in cyclooxgenase 2 and inducible nitric oxide synthase gene expression levels in HepG2 cells. Compounds 1, 3, 5, 6, 8, and 9 significantly activated the transcription of PPARs in a dose-dependent manner, with EC₅₀ values ranging from 1.1 to 13.0 μM. Compounds 1, 3, 5, 6, 8, and 9 exhibited dose-dependent PPARα transactivational activity, with EC₅₀ values in a range of 0.9 - 16.0 μM. Compounds 1, 3, 8, and 9 also significantly upregulated PPARγ activity in a dose-dependent manner, with EC₅₀ values of 10.5, 6.6, 15.7, and 1.6 μM, whereas compounds 1, 8, and 9 demonstrated transactivational PPARβ(δ) effects with EC₅₀ values of 11.4, 10.3, and 1.5 μM, respectively. These results provide a scientific rationale for the use of the roots of S. flavescens and warrant further studies to develop new agents for the prevention and treatment of inflammatory and metabolic diseases. Copyright © 2012 John Wiley & Sons, Ltd.

Tangeretin, a citrus polymethoxyflavonoid, induces apoptosis of human gastric cancer AGS cells through extrinsic and intrinsic signaling pathways.

PubMed

Dong, Yang; Cao, Aili; Shi, Jianrong; Yin, Peihao; Wang, Li; Ji, Guang; Xie, Jianqun; Wu, Dazheng

2014-04-01

Tangeretin, a natural polymethoxyflavone present in citrus peel oil, is known to have anticancer activities in breast cancer, colorectal carcinoma and lung carcinoma, yet, the underlying mechanisms of tangeretin in human gastric cancer AGS cells have not been investigated to date. In the present study, the apoptotic mechanisms of tangeretin in AGS cells were explored. It was observed that tangeretin increased the apoptotic rates of AGS cells following treatment with tangeretin for 48 h in a dose-dependent manner by Annexin V-FITC and PI double staining. In addition, characteristic apoptotic morphology such as nuclear shrinkage and apoptotic bodies was observed after Hoechst 33258 staining. Flow cytometric assay showed that treatment of AGS cells with tangeretin decreased the mitochondrial membrane potential (MMP) in a dose-dependent manner, which indicated that mitochondrial dysfunction was involved in the tangeretin-induced apoptosis. Caspase-3, -8 and -9 activities were increased by tangeretin in a dose-dependent manner. Western blotting showed that the protein levels of pro-apoptotic proteins including cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax, Bid, tBid, p53, p21/cip1, Fas and FasL were significantly upregulated by tangeretin. In addition, PFT-α (a p53 inhibitor) reduced the apoptotic rates and the expression of p53, p21, caspase-3 and caspase-9 induced by tangeretin, indicating that tangeretin-induced apoptosis was p53-dependent. In conclusion, these results suggest that tangeretin induces the apoptosis of AGS cells mainly through p53-dependent mitochondrial dysfunction and the Fas/FasL-mediated extrinsic pathway.

Pertussis toxin-sensitive G-protein mediates the alpha 2-adrenergic receptor inhibition of melatonin release in photoreceptive chick pineal cell cultures

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

Pratt, B.L.; Takahashi, J.S.

The avian pineal gland is a photoreceptive organ that has been shown to contain postjunctional alpha 2-adrenoceptors that inhibit melatonin synthesis and/or release upon receptor activation. Physiological response and (32P)ADP ribosylation experiments were performed to investigate whether pertussis toxin-sensitive guanine nucleotide-binding proteins (G-proteins) were involved in the transduction of the alpha 2-adrenergic signal. For physiological response studies, the effects of pertussis toxin on melatonin release in dissociated cell cultures exposed to norepinephrine were assessed. Pertussis toxin blocked alpha 2-adrenergic receptor-mediated inhibition in a dose-dependent manner. Pertussis toxin-induced blockade appeared to be noncompetitive. One and 10 ng/ml doses of pertussis toxinmore » partially blocked and a 100 ng/ml dose completely blocked norepinephrine-induced inhibition. Pertussis toxin-catalyzed (32P)ADP ribosylation of G-proteins in chick pineal cell membranes was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Membranes were prepared from cells that had been pretreated with 0, 1, 10, or 100 ng/ml pertussis toxin. In the absence of pertussis toxin pretreatment, two major proteins of 40K and 41K mol wt (Mr) were labeled by (32P)NAD. Pertussis toxin pretreatment of pineal cells abolished (32P) radiolabeling of the 40K Mr G-protein in a dose-dependent manner. The norepinephrine-induced inhibition of both cAMP efflux and melatonin release, as assessed by RIA of medium samples collected before membrane preparation, was also blocked in a dose-dependent manner by pertussis toxin. Collectively, these results suggest that a pertussis toxin-sensitive 40K Mr G-protein labeled by (32P)NAD may be functionally associated with alpha 2-adrenergic signal transduction in chick pineal cells.« less

Dose-dependent heart rate reducing effect of nizatidine, a histamine H2-receptor antagonist.

PubMed Central

Hinrichsen, H; Halabi, A; Fuhrmann, G; Kirch, W

1993-01-01

1. Twelve healthy subjects were treated in a randomised placebo-controlled crossover study with placebo, 150 mg, 300 mg, and 600 mg nizatidine, 100 mg pirenzepine, and 300 mg nizatidine plus 100 mg pirenzepine for 1 week each. 2. On the seventh treatment day, heart rate, blood pressure, systolic time intervals, impedance cardiographic and Doppler ultrasound variables were measured. 3. Stroke volume and blood pressure were not altered by nizatidine and/or pirenzepine. By contrast, heart rate and cardiac output significantly (P < 0.05) decreased in a dose-dependent manner 1.5 and 3 h after administration of 300 and 600 mg nizatidine. Treatment with 150 mg nizatidine led to similar though non-significant trends. 4. While a slightly insignificant rise in heart rate was detected with pirenzepine alone, heart rate and cardiac output remained unchanged upon combined nizatidine and pirenzepine treatment as compared with placebo and baseline values. 5. In conclusion, nizatidine reduced heart rate and cardiac output in a dose-dependent manner, whereas this negative chronotropic effect was counteracted by concurrent administration of the anti-cholinergic drug pirenzepine. PMID:8099802

Calcium signals and caspase-12 participated in paraoxon-induced apoptosis in EL4 cells.

PubMed

Li, Lan; Cao, Zhiheng; Jia, Pengfei; Wang, Ziren

2010-04-01

In order to investigate whether calcium signals participate in paraoxon (POX)-induced apoptosis in EL4 cells, real-time laser scanning confocal microscopy (LSCM) was used to detect Ca(2+) changes during the POX application. Apoptotic rates of EL4 cells and caspase-12 expression were also evaluated. POX (1-10nM) increased intracellular calcium concentration ([Ca(2+)]i) in EL4 cells in a dose-dependent manner at early stage (0-2h) of POX application, and apoptotic rates of EL4 cells after treatment with POX for 16h were also increased in a dose-dependent manner. Pre-treatment with EGTA, heparin or procaine attenuated POX-induced [Ca(2+)]i elevation and apoptosis. Additionally, POX up-regulated caspase-12 expression in a dose-dependent manner, and pre-treatment with EGTA, heparin or procaine significantly inhibited POX-induced increase of caspase-12 expression. Our results suggested that POX induced [Ca(2+)]i elevation in EL4 cells at the early stage of POX-induced apoptosis, which might involve Ca(2+) efflux from the endoplasmic reticulum (ER) and Ca(2+) influx from extracellular medium. Calcium signals and caspase-12 were important upstream messengers in POX-induced apoptosis in EL4 cells. The ER-associated pathway possibly operated in this apoptosis. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Oxytocin prevents cartilage matrix destruction via regulating matrix metalloproteinases.

PubMed

Wu, Yixin; Wu, Tongyu; Xu, Binbin; Xu, Xiaoyan; Chen, Honggan; Li, Xiyao

2017-05-06

Degradation of the extracellular matrix type II Collagen (Col II) induced by proinflammatory cytokines such as tumor necrosis factor-α (TNF-α) is an important hallmark of Osteoarthritis (OA). Oxytocin (OT) is a well-known neurohypophysical hormone that is synthesized in the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus. In this study, we have found that oxytocin receptor (OTR) was expressed in human primary chondrocytes, and the expression of which was reduced in chondrocytes from OA patients and in response to TNF-α treatment in a dose dependent manner. Notably, it was shown that TNF-α -induced degradation of Col II was restored by treatment with OT in a dose-dependent manner. In addition, TNF-α treatment (10 ng/mL) highly elevated the expression of MMP-1 and MMP-13 in SW1353 chondrocytes, which were reversed by OT in a dose dependent manner at both gene and protein expression levels. In addition, it was demonstrated that the JAK2/STAT1 pathway was involved in the restoration effects of OT in the degradation of Col II. Lastly, knockdown of OTR abolished the inhibitory effects of OT on the degradation of col II and the induction of MMP-1 and MMP-13 expression, suggesting the involvement of OTR. Our study implied the therapeutic potential of OT for cartilage degradation. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of tributyltin on testicular development in Sebastiscus marmoratus and the mechanism involved.

PubMed

Zhang, Jiliang; Zuo, Zhenghong; He, Chengyong; Cai, Jiali; Wang, Yuqing; Chen, Yixin; Wang, Chonggang

2009-07-01

Organotin compounds, such as tributyltin (TBT), that have been used as antifouling biocides can induce masculinization in female mollusks. However, few studies addressing the effects of TBT on fishes have been reported. The present study was conducted to investigate the effects of TBT at environmentally relevant concentrations (1, 10, and 100 ng/L) on testicular development in Sebastiscus marmoratus and to gain insight into its mechanism of action. After exposure for 48 d, the gonadosomatic index had decreased in a dose-dependent manner. Although the testosterone levels in the testes were elevated and the 17beta-estradiol levels were decreased, spermatogenesis was suppressed. Moreover, gamma-glutamyl transpeptidase activity (which is used as a Sertoli cell marker) was decreased in a dose-dependent manner after TBT exposure, and serious interstitial fibrosis was observed in the interlobular septa of the testes in the 100 ng/L TBT test group. Increases in the retinoid X receptors and peroxisome proliferator activated receptor gamma expression and the progressive enlargement of lipid droplets in the testes were observed after TBT exposure. Estrogen receptor alpha levels in the testes of the fish exposed to TBT decreased in a dose-dependent manner. The reduction of estrogen receptor alpha mRNA resulted from the decrease of 17beta-estradiol levels, and the progressive enlargement of lipid droplets may have contributed to the dysfunction of the Sertoli cells, which then disrupted spermatogenesis.

Oxymatrine inhibits the proliferation of prostate cancer cells in vitro and in vivo

PubMed Central

WU, CUNZAO; HUANG, WEIPING; GUO, YONG; XIA, PENG; SUN, XIANBIN; PAN, XIAODONG; HU, WEILIE

2015-01-01

Oxymatrine is an alkaloid, which is derived from the traditional Chinese herb, Sophora flavescens Aiton. Oxymatrine has been shown to exhibit anti-inflammatory, antiviral, and anticancer properties. The present study aimed to investigate the anticancer effects of oxymatrine in human prostate cancer cells, and the underlying molecular mechanisms of these effects. An MTT assay demonstrated that oxymatrine significantly inhibited the proliferation of prostate cancer cells in a time- and dose-dependent manner. In addition, flow cytometry and a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay suggested that oxymatrine treatment may induce prostate cancer cell apoptosis in a dose-dependent manner. Furthermore, western blot analysis demonstrated a significant increase in the expression of p53 and bax, and a significant decrease in that of Bcl-2, in prostrate cancer cells in a dose-dependent manner. In vivo analysis demonstrated that oxymatrine inhibited tumor growth following subcutaneous inoculation of prostate cancer cells into nude mice. The results of the present study suggested that the antitumor properties of oxymatrine, may be associated with the inhibition of cell proliferation, and induction of apoptosis, via the regulation of apoptosis-associated gene expression. Therefore, the results may provide a novel approach for the development of prostate cancer therapy using oxymatrine, which is derived from the traditional Chinese herb, Sophora flavescens. PMID:25672672

Low‑dose radiation‑induced apoptosis in human leukemia K562 cells through mitochondrial pathways.

PubMed

Xin, Yong; Zhang, Hai-Bin; Tang, Tian-You; Liu, Gui-Hong; Wang, Jian-She; Jiang, Guan; Zhang, Long-Zhen

2014-09-01

High‑dose total body irradiation (TBI) has an established role as preparative regimen for bone‑marrow transplantation in the treatment of chronic myelogenous leukemia (CML), but this regimen still has a relatively high rate of acute and late toxicity. Low‑dose radiation (LDR) induces apoptosis of tumor cells and has numerous beneficial effects on normal tissues, including radiation homeostasis and adaptive response. Based on the previous evidence, in the present study, K562 cells were exposed to LDR, high‑dose radiation (HDR), and LDR in combination with HDR to investigate the possible mechanism of the apoptotic effect and hypersensitivity induced by LDR. The apoptotic rate increased in all radiation groups in a time‑dependent manner. An upregulation of Bax protein expression and a downregulation of Bcl‑xl in a dose‑dependent manner in human leukemia K562 cells was observed. However, the expression of p53 protein did not change in all of the radiation cell groups. The mitochondrial membrane potential (ΔΨm) in K562 cells decreased in all of the radiation cell groups in a dose‑dependent manner. Furthermore, the decrease of ΔΨm was enhanced in the LDR/HDR group compared with that in the LDR or HDR groups. The activity of caspase‑3 was enhanced in all of the radiation groups. In the LDR/HDR group, the activity of caspase‑3 was higher than that in the HDR or LDR groups. The present study provided preliminary experimental evidence of LDR being beneficial in combination with TBI in the treatment of CML.

Time dependent pre-treatment EPID dosimetry for standard and FFF VMAT.

PubMed

Podesta, Mark; Nijsten, Sebastiaan M J J G; Persoon, Lucas C G G; Scheib, Stefan G; Baltes, Christof; Verhaegen, Frank

2014-08-21

Methods to calibrate Megavoltage electronic portal imaging devices (EPIDs) for dosimetry have been previously documented for dynamic treatments such as intensity modulated radiotherapy (IMRT) using flattened beams and typically using integrated fields. While these methods verify the accumulated field shape and dose, the dose rate and differential fields remain unverified. The aim of this work is to provide an accurate calibration model for time dependent pre-treatment dose verification using amorphous silicon (a-Si) EPIDs in volumetric modulated arc therapy (VMAT) for both flattened and flattening filter free (FFF) beams. A general calibration model was created using a Varian TrueBeam accelerator, equipped with an aS1000 EPID, for each photon spectrum 6 MV, 10 MV, 6 MV-FFF, 10 MV-FFF. As planned VMAT treatments use control points (CPs) for optimization, measured images are separated into corresponding time intervals for direct comparison with predictions. The accuracy of the calibration model was determined for a range of treatment conditions. Measured and predicted CP dose images were compared using a time dependent gamma evaluation using criteria (3%, 3 mm, 0.5 sec). Time dependent pre-treatment dose verification is possible without an additional measurement device or phantom, using the on-board EPID. Sufficient data is present in trajectory log files and EPID frame headers to reliably synchronize and resample portal images. For the VMAT plans tested, significantly more deviation is observed when analysed in a time dependent manner for FFF and non-FFF plans than when analysed using only the integrated field. We show EPID-based pre-treatment dose verification can be performed on a CP basis for VMAT plans. This model can measure pre-treatment doses for both flattened and unflattened beams in a time dependent manner which highlights deviations that are missed in integrated field verifications.

Antiviral effect of lithium chloride on infection of cells by canine parvovirus.

PubMed

Zhou, Pei; Fu, Xinliang; Yan, Zhongshan; Fang, Bo; Huang, San; Fu, Cheng; Hong, Malin; Li, Shoujun

2015-11-01

Canine parvovirus type 2 causes significant viral disease in dogs, with high morbidity, high infectivity, and high mortality. Lithium chloride is a potential antiviral drug for viruses. We determined the antiviral effect of Lithium Chloride on canine parvovirus type 2 in feline kidney cells. The viral DNA and proteins of canine parvovirus were suppressed in a dose-dependent manner by lithium chloride. Further investigation verified that viral entry into cells was inhibited in a dose-dependent manner by lithium chloride. These results indicated that lithium chloride could be a potential antiviral drug for curing dogs with canine parvovirus infection. The specific steps of canine parvovirus entry into cells that are affected by lithium chloride and its antiviral effect in vivo should be explored in future studies.

[The anti-tumour effect of Wuxing soup and its mechanism in inducing apoptosis of tumour cells mediated by calcium].

PubMed

Mo, Fei; Hu, Jing-Ying; Gan, Yu; Zhao, Yang-Xing; Zhao, Xin-Tai

2008-09-01

To confirm the anti-cancer effect and mechanism of Wuxing soup. Inhibition of cellular growth under Wuxing soup treatment was observed by MTT; Apoptosis was detected by gel electrophoresis, transmission electron microscopy and FACS; The concentration of calcium was measured by fluorescence probe. After SGC-7901 cell being treated by Wuxing soup, it showed that: 1) Wuxing soup could specifically inhibit cancer cells proliferation in a time and dose dependent manner; 2) Typical apoptotic morphological changes and DNA ladder of SGC-7901 cells were observed; 3) calcium inhibitor Bapta AM could reduce the apoptotic rate and protect SGC-7901 cells in a dose dependent manner. Wuxing soup has an effective inhibition on cancer cells, and can induce SGC-7901 cells to apoptosis by calcium.

Effects of illumination on human nocturnal serum melatonin levels and performance

NASA Technical Reports Server (NTRS)

Dollins, A. B.; Lynch, H. J.; Wurtman, R. J.; Deng, M. H.; Lieberman, H. R.

1993-01-01

In humans, exposure to bright light at night suppresses the normal nocturnal elevation in circulating melatonin. Oral administration of pharmacological doses of melatonin during the day, when melatonin levels are normally minimal, induces fatigue. To examine the relationship between illumination, human pineal function, and behavior, we monitored the overnight serum melatonin profiles and behavioral performance of 24 healthy male subjects. On each of three separate occasions subjects participated in 13.5 h (1630-0800 h) testing sessions. Each subject was assigned to an individually illuminated workstation that was maintained throughout the night at an illumination level of approximately 300, 1500, or 3000 lux. Melatonin levels were significantly diminished by light treatment, F(2, 36) = 12.77, p < 0.001, in a dose-dependent manner. Performance on vigilance, reaction time, and other tasks deteriorated throughout the night, consistent with known circadian variations in these parameters, but independent of ambient light intensity and circulating melatonin levels.

Apples prevent mammary tumors in rats.

PubMed

Liu, Rui Hai; Liu, Jiaren; Chen, Bingqing

2005-03-23

Regular consumption of fruits and vegetables has been consistently shown to be associated with reduced risk of developing chronic diseases such as cancer and cardiovascular disease. Apples are commonly consumed and are the major contributors of phytochemicals in human diets. It was previously reported that apple extracts exhibit strong antioxidant and antiproliferative activities and that the major part of total antioxidant activity is from the combination of phytochemicals. Phytochemicals, including phenolics and flavonoids, are suggested to be the bioactive compounds contributing to the health benefits of apples. Here it is shown that whole apple extracts prevent mammary cancer in a rat model in a dose-dependent manner at doses comparable to human consumption of one, three, and six apples a day. This study demonstrated that whole apple extracts effectively inhibited mammary cancer growth in the rat model; thus, consumption of apples may be an effective strategy for cancer protection.

Immunomodulatory effects of ethanol extract of germinated ice plant (Mesembryanthemum crystallinum)

PubMed Central

Choi, Joo-Hee; Jo, Sung-Gang; Jung, Seoung-Ki; Park, Woo-Tae; Kim, Keun-Young; Park, Yong-Wook

2017-01-01

The purpose of this study was to investigate the immunomodulatory activity of ice plant (Mesembryanthemum crystallinum) extract (IPE) in vitro and in vivo. Raji (a human B cell line) and Jurkat (a human T cell line) cells were treated with various doses of IPE and cell proliferation was measured by WST assay. Results showed that IPE promoted the proliferation of both Raji and Jurkat cells in a dose-dependent manner. IPE also enhanced IL-6 and TNF-α production in macrophages in the presence of lipopolysaccharide (LPS), although IPE alone did not induce cytokine production. Moreover, IPE treatment upregulated iNOS gene expression in macrophages in a time- and dose-dependent manner and led to the production of nitric oxide in macrophages in the presence of IFNγ. In vivo studies revealed that oral administration of IPE for 2 weeks increased the differentiation of CD4+, CD8+, and CD19+ cells in splenocytes. These findings suggested that IPE has immunomodulatory effects and could be developed as an immunomodulatory supplement. PMID:28400837

Effects of rosuvastatin on the production and activation of matrix metalloproteinase-2 and migration of cultured rat vascular smooth muscle cells induced by homocysteine.

PubMed

Shi, Ya-fei; Chi, Ju-fang; Tang, Wei-liang; Xu, Fu-kang; Liu, Long-bin; Ji, Zheng; Lv, Hai-tao; Guo, Hang-yuan

2013-08-01

To test the influence of homocysteine on the production and activation of matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase-2 (TIMP-2) and on cell migration of cultured rat vascular smooth muscle cells (VSMCs). Also, to explore whether rosuvastatin can alter the abnormal secretion and activation of MMP-2 and TIMP-2 and migration of VSMCs induced by homocysteine. Rat VSMCs were incubated with different concentrations of homocysteine (50-5000 μmol/L). Western blotting and gelatin zymography were used to investigate the expressions and activities of MMP-2 and TIMP-2 in VSMCs in culture medium when induced with homocysteine for 24, 48, and 72 h. Transwell chambers were employed to test the migratory ability of VSMCs when incubated with homocysteine for 48 h. Different concentrations of rosuvastatin (10(-9)-10(-5) mol/L) were added when VSMCs were induced with 1000 μmol/L homocysteine. The expressions and activities of MMP-2 and TIMP-2 were examined after incubating for 24, 48, and 72 h, and the migration of VSMCs was also examined after incubating for 48 h. Homocysteine (50-1000 μmol/L) increased the production and activation of MMP-2 and expression of TIMP-2 in a dose-dependent manner. However, when incubated with 5000 μmol/L homocysteine, the expression of MMP-2 was up-regulated, but its activity was down-regulated. Increased homocysteine-induced production and activation of MMP-2 were reduced by rosuvastatin in a dose-dependent manner whereas secretion of TIMP-2 was not significantly altered by rosuvastatin. Homocysteine (50-5000 μmol/L) stimulated the migration of VSMCs in a dose-dependent manner, but this effect was eliminated by rosuvastatin. Homocysteine (50-1000 μmol/L) significantly increased the production and activation of MMP-2, the expression of TIMP-2, and the migration of VSMCs in a dose-dependent manner. Additional extracellular rosuvastatin can decrease the excessive expression and activation of MMP-2 and abnormal migration of VSMCs induced by homocysteine.

Adenosine triphosphate regulates the activity of guinea pig Cav1.2 channel by direct binding to the channel in a dose-dependent manner.

PubMed

Feng, Rui; Xu, Jianjun; Minobe, Etsuko; Kameyama, Asako; Yang, Lei; Yu, Lifeng; Hao, Liying; Kameyama, Masaki

2014-05-01

The present study is to investigate the mechanism by which ATP regulates Cav1.2 channel activity. Ventricular tissue was obtained from adult guinea pig hearts using collagenase. Ca(2+) channel activity was monitored using the patch-clamp technique. Proteins were purified using wheat germ agglutinin-Sepharose, and the concentration was determined using the Coomassie brilliant blue technique. ATP binding to the Cav1.2 channel was examined using the photoaffinity method. EDA-ATP-biotin maintains Ca(2+) channel activity in inside-out membrane patches. ATP directly bound to the Cav1.2 channel in a dose-dependent manner, and at least two molecules of ATP bound to one molecule of the Cav1.2 channel. Low levels of calmodulin (CaM) increased ATP binding to the Cav1.2 channel, but higher levels of CaM decreased ATP binding to the Cav1.2 channel. In addition, Ca(2+) was another regulator for ATP binding to the Cav1.2 channel. Furthermore, ATP bound to GST-fusion peptides of NH2-terminal region (amino acids 6-140) and proximal COOH-terminal region (amino acids 1,509-1,789) of the main subunit (α1C) of the Cav1.2 channel. Our data suggest that ATP might regulate Cav1.2 channel activity by directly binding to the Cav1.2 channel in a dose-dependent manner. In addition, the ATP-binding effect to the Cav1.2 channel was both CaM- and Ca(2+) dependent.

Enhancing venetoclax activity in acute myeloid leukemia by co-targeting MCL1.

PubMed

Teh, T-C; Nguyen, N-Y; Moujalled, D M; Segal, D; Pomilio, G; Rijal, S; Jabbour, A; Cummins, K; Lackovic, K; Blombery, P; Thompson, E; Ekert, P G; Lessene, G; Glaser, S P; Huang, D C S; Roberts, A W; Guthridge, M A; Wei, A H

2018-02-01

Targeted therapies are frequently combined with standard cytotoxic drugs to enhance clinical response. Targeting the B-cell lymphoma 2 (BCL-2) family of proteins is an attractive option to combat chemoresistance in leukemia. Preclinical and clinical studies indicate modest single-agent activity with selective BCL-2 inhibitors (for example, venetoclax). We show that venetoclax synergizes with cytarabine and idarubicin to increase antileukemic efficacy in a TP53-dependent manner. Although TP53 deficiency impaired sensitivity to combined venetoclax and chemotherapy, higher-dose idarubicin was able to suppress MCL1 and induce cell death independently of TP53. Consistent with an MCL1-specific effect, cell death from high-dose idarubicin was dependent on pro-apoptotic Bak. Combining higher-dose idarubicin with venetoclax was able to partially overcome resistance in Bak-deficient cells. Using inducible vectors and venetoclax to differentially target anti-apoptotic BCL-2 family members, BCL-2 and MCL1 emerged as critical and complementary proteins regulating cell survival in acute myeloid leukemia. Dual targeting of BCL-2 and MCL1, but not either alone, prolonged survival of leukemia-bearing mice. In conclusion, our findings support the further investigation of venetoclax in combination with standard chemotherapy, including intensified doses of idarubicin. Venetoclax should also be investigated in combination with direct inhibitors of MCL1 as a chemotherapy-free approach in the future.

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

PubMed

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

2017-10-01

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

By improving regional cortical blood flow, attenuating mitochondrial dysfunction and sequential apoptosis galangin acts as a potential neuroprotective agent after acute ischemic stroke.

PubMed

Li, Shaojing; Wu, Chuanhong; Zhu, Li; Gao, Jian; Fang, Jing; Li, Defeng; Fu, Meihong; Liang, Rixin; Wang, Lan; Cheng, Ming; Yang, Hongjun

2012-11-09

Ischemic stroke is a devastating disease with a complex pathophysiology. Galangin is a natural flavonoid isolated from the rhizome of Alpina officinarum Hance, which has been widely used as an antioxidant agent. However, its effects against ischemic stroke have not been reported and its related neuroprotective mechanism has not really been explored. In this study, neurological behavior, cerebral infarct volumes and the improvement of the regional cortical blood flow (rCBF) were used to evaluate the therapeutic effect of galangin in rats impaired by middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia. Furthermore, the determination of mitochondrial function and Western blot of apoptosis-related proteins were performed to interpret the neuroprotective mechanism of galangin. The results showed that galangin alleviated the neurologic impairments, reduced cerebral infarct at 24 h after MCAO and exerted a protective effect on the mitochondria with decreased production of mitochondrial reactive oxygen species (ROS). These effects were consistent with improvements in the membrane potential level (Dym), membrane fluidity, and degree of mitochondrial swelling in a dose-dependent manner. Moreover, galangin significantly improved the reduced rCBF after MCAO. Western blot analysis revealed that galangin also inhibited apoptosis in a dose-dependent manner concomitant with the up-regulation of Bcl-2 expression, down-regulation of Bax expression and the Bax/Bcl-2 ratio, a reduction in cytochrome c release from the mitochondria to the cytosol, the reduced expression of activated caspase-3 and the cleavage of poly(ADP-ribose) polymerase (PARP). All these data in this study demonstrated that galangin might have therapeutic potential for ischemic stroke and play its protective role through the improvement in rCBF, mitochondrial protection and inhibiting caspase-dependent mitochondrial cell death pathway for the first time.

Rosuvastatin enhances the catabolism of LDL apoB-100 in subjects with combined hyperlipidemia in a dose dependent manner

USDA-ARS?s Scientific Manuscript database

Dose-associated effects of rosuvastatin on the metabolism of apolipoprotein (apo) B-100 in triacylglycerol rich lipoprotein (TRL, d < 1.019 g/ml) and low density lipoprotein (LDL) and of apoA-I in high density lipoprotein (HDL) were assessed in subjects with combined hyperlipidemia. Our primary hypo...

Hepatic glutathione metabolism and lipid peroxidation in response to excess dietary selenomethionine and selenite in mallard ducklings

USGS Publications Warehouse

Hoffman, D.J.; Heinz, G.H.; Krynitsky, A.J.

1989-01-01

Selenium from selenomethionine accumulated in a dose-dependent manner in the liver, resulting in a decrease in hepatic-reduced glutathione with a corresponding decrease in total hepatic thiols. There was a dose-dependent increase in the oxidized to reduced glutathione ratio, and an increase in lipid peroxidation. These findings indicate that Se in the diet at 10 ppm and higher causes significant sublethal alterations in mallard ducklings, and 20-40 ppm causes significant hepatotoxicity.

Evaluation of ameliorative potential of supranutritional selenium on enrofloxacin-induced testicular toxicity.

PubMed

Rungsung, Soya; Khan, Adil Mehraj; Sood, Naresh Kumar; Rampal, Satyavan; Singh Saini, Simrat Pal

2016-05-25

The study was designed to assess the ameliorative potential of selenium (Se) on enrofloxacin-induced testicular toxicity in rats. There was a significant decrease in body weight and non-significant decrease in mean testicular weight of enrofloxacin treated rats. In enrofloxacin treated rats, total sperm count and viability decreased where as sperm abnormalities increased. Testicular histopathology revealed dose dependent dysregulation of spermatogenesis and presence of necrotic debris in seminiferous tubules which was marginally improved with Se. Enrofloxacin also produced a dose dependent decrease in testosterone level. The activity of testicular antioxidant enzymes decreased where as lipid peroxidation increased in a dose-dependent manner. Se supplementation partially restored oxidative stress and sperm damage and did not affect the plasma concentrations of enrofloxacin or ciprofloxacain. The results indicate that enrofloxacin produces a dose-dependent testicular toxicity in rats that is moderately ameliorated with supranutritional Se. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Antioxidant and immunoregulatory activity of alkali-extractable polysaccharides from mung bean.

PubMed

Yao, Yang; Zhu, Yingying; Ren, Guixing

2016-03-01

Alkali-extractable polysaccharides from the seeds of mung beans and two polysaccharide sub-fractions (MAP-1 and MAP-2) were isolated and purified by anion-exchange and gel filtration chromatography. The average molecular weights (Mws) of MAP-1 and MAP-2 were 94.2 kDa and 60.4 kDa, respectively. Monosaccharide component analysis indicated that MAP-1 was composed of Rha, Ara, Glu, Gal, and GalA in a molar ratio of 1.1:0.4:0.7:0.5:0.3. MAP-2 consisted of Xyl, Rha, Gal, Glu and GalA with a relative molar ratio of 0.4:1.4:1.6:0.5:0.2. Antioxidant assays indicated that both MAP-1 and MAP-2 exhibit significant antioxidant activity in a dose-dependent manner. An in vitro study further showed that MAP-1 and MAP-2 were both able to stimulate the production of secretory molecules (NO, TNF-α and IL-6) by RAW 264.7 murine macrophages in a concentration-dependent manner. These findings suggest that the polysaccharides isolated in our study have immunoregulatory effects on macrophages and can be used as a beneficial health food. Copyright © 2015. Published by Elsevier B.V.

Evaluation of CNS activities of aerial parts of Cynodon dactylon Pers. in mice.

PubMed

Pal, Dilipkumar

2008-01-01

The dried extracts of aerial parts of Cynodon dactylon Pers. (Graminae) were evaluated for CNS activities in mice. The ethanol extract of aerial parts of C. dactylon (EECD) was found to cause significant depression in general behavioral profiles in mice. EECD significantly potentiated the sleeping time in mice induced by standard hypnotics viz. pentobarbitone sodium, diazepam, and meprobamate in a dose dependant manner. EECD showed significant analgesic properties as evidenced by the significant reduction in the number of writhes and stretches induced in mice by 1.2% acetic acid solution. It also potentiated analgesia induced by morphine and pethidine in mice. EECD inhibited the onset and the incidence of convulsion in a dose dependent manner against pentylenetetrazole (PTZ)-induced convulsion. The present study indicates that EECD has significant CNS depressant activities.

Consequences of copper treatment on pigeon pea photosynthesis, osmolytes and antioxidants defense.

PubMed

Sharma, Poonam; Sirhindi, Geetika; Singh, Anil Kumar; Kaur, Harpreet; Mushtaq, Ruqia

2017-10-01

An attempt was made to explore the effect of copper sulphate treatment on growth, photosynthesis, osmolytes and antioxidants in 15 days old seedlings of C. cajan (Pigeonpea). C. cajan seedlings were grown in 0, 1, 5 and 10 mM concentrations of copper sulphate in petriplates lined with Whatman filter paper for 15 days. Root length and shoot length was decreased in a dose dependent manner with highest decrease of 82.80 and 45.92% in 10 mM Cu stress. Photosynthetic efficiency (qP, qN and Y) was decreased in a dose dependent manner whereas NPQ was increased in 1 and 5 mM and decreased in 10 mM Cu. Photosynthetic pigments viz total chlorophyll and carotenoids were increased in low concentrations and decreased in high concentrations of Cu. Osmolytes such as proline, glycine betaine and sugars were found to be increased in a dose dependent manner. Similarly antioxidants such as superoxide dismutase and catalase increased to 129.17 and 169.7%, respectively under Cu stress. Vitamin C and vitamin E was also increased in different concentrations of Cu to a significant level. It can be concluded from the present study that C. cajan can tolerate Cu stress up to 5 mM by adjusting the proportion of proline, glycine betaine, sugars and vitamins along with increasing the activity of some of the antioxidant enzymes.

Proinflammatory activation of macrophages by bisphenol A-glycidyl-methacrylate involved NFκB activation via PI3K/Akt pathway.

PubMed

Kuan, Yu-Hsiang; Huang, Fu-Mei; Li, Yi-Ching; Chang, Yu-Chao

2012-11-01

Bisphenol A-glycidyl-methacrylate (BisGMA), a dental composite resin and dentin bonding agent, might prompt inflammatory effects to adjacent tissues. Macrophages are a major cellular component of the inflammatory sites. Little is known about the mechanisms of BisGMA on macrophages activation. The aim of this study was to evaluate BisGMA on proinflammatory mediators generation of murine macrophage RAW264.7 cells. IL-1β and IL-6 were analyzed by enzyme-linked immunosorbent assay. Nitric oxide, extracellular superoxide anion, and intracellular reaction oxygen species were measured by Griess assay, ferricytochrome c, and 2',7'-dichlorofluorescein assay, respectively. Expression of iNOS, p-p65, IκB, and p-Akt was analyzed by Western blotting. BisGMA augmented the generation of IL-1β, IL-6, nitric oxide and the expression of iNOS in a time- and dose-dependent manner (p<0.05). BisGMA enhanced the generation of intracellular and extracellular ROS in a dose-dependent manner (p<0.05). The levels of p65 phosphorylation, IκB degradation, and Akt phosphorylation were found to be increased in a time- and dose-dependent manner (p<0.05). These results indicate that BisGMA could induce nitric oxide, ROS, and inflammatory cytokines in macrophages. In addition, BisGMA may active macrophage via NF-κB activation, IκB degradation, and p-Akt activation. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

P2X and P2Y Receptors Mediate Contraction Induced by Electrical Field Stimulation in Feline Esophageal Smooth Muscle.

PubMed

Cho, Young Rae; Jang, Hyeon Soon; Kim, Won; Park, Sun Young; Sohn, Uy Dong

2010-10-01

It is well-known that electrical field stimulation (EFS)-induced contraction is mediated by a cholinergic mechanism and other neurotransmitters. NO, ATP, calcitonin gene-related peptide (CGRP), and substance P are released by EFS. To investigate the purinergic mechanism involved in the EFS-induced contraction, purinegic receptors antagonists were used. Suramine, a non-selective P2 receptor antagonist, reduced the contraction induced by EFS. NF023 (10(-7)~10(-4) M), a selective P2X antagonist, inhibited the contraction evoked by EFS. Reactive blue (10(-6)~10(-4) M), selective P2Y antagonist, also blocked the contraction in a dose-dependent manner. In addition, P2X agonist α,β-methylene 5'-adenosine triphosphate (αβMeATP, 10(-7)~10(-5) M) potentiated EFS-induced contraction in a dose-dependent manner. P2Y agonist adenosine 5'-[β-thio]diphosphate trilithium salt (ADPβS, 10(-7)~10(-5) M) also potentiated EFS-induced contractions in a dose-dependent manner. Ecto-ATPase activator apyrase (5 and 10 U/ml) reduced EFS-induced contractions. Inversely, 6-N,N-diethyl-D-β,γ-dibromomethylene 5'-triphosphate triammonium (ARL 67156, 10(-4) M) increased EFS-induced contraction. These data suggest that endogenous ATP plays a role in EFS-induced contractions which are mediated through both P2X-receptors and P2Y-receptors stimulation in cat esophageal smooth muscle.

Possible biochemical effects following inhibition of ethanol-induced gastric mucosa damage by Gymnema sylvestre in male Wistar albino rats.

PubMed

Al-Rejaie, Salim S; Abuohashish, Hatem M; Ahmed, Mohammed M; Aleisa, Abdulaziz M; Alkhamees, Osama

2012-12-01

Gymnema sylvestre (GS) R. Br. (Gymnema) (Asclepiadaceae) has been used from ancient times as a folk medicine for the treatment of diabetes, obesity, urinary disorder, and stomach stimulation. The present study was designed to investigate the effects of G. sylvestre leaves ethanol extract on gastric mucosal injury in rats. Gastric mucosal damage was induced by 80% ethanol in 36 h fasted rats. The effect of G. sylvestre on gastric secretions induced in Shay rats was estimated. In stomach, wall mucus, non-protein sulfhydryl groups (NP-SH), malondialdehyde (MDA), total proteins and nucleic acids levels were estimated. Histopathological changes were observed. G. sylvestre pretreatment at doses of 100, 200 and 400 mg/kg provided 27, 49, and 63% protection against the ulcerogenic effect of ethanol, respectively. Pylorus ligation accumulated 10.24 mL gastric secretions with 66.56 mEq of acidity in control rats. Pretreatment with G. sylvestre significantly inhibited the secretions volume and acidity in dose-dependent manner. Ethanol caused significant depletion in stomach-wall mucus (p < 0.001), total proteins (p < 0.01), nucleic acids (p < 0.001), and NP-SH (p < 0.001) levels. Pretreatment with G. sylvestre showed protection against these depleted levels in dose-dependent manner. The MDA levels increased from 19.02 to 29.22 nmol/g by ethanol ingestion and decreased with G. sylvestre pretreatments in dose-dependent manner. The protective effect of G. sylvestre observed in the present study is attributed to its effect on mucus production, increase in nucleic acid and NP-SH levels, which appears to be mediated through its free radical scavenging ability and/or possible cytoprotective properties.

Inhibition of Histone Deacetylases (HDACs) and mTOR Signaling: Novel Strategies Toward the Treatment of Prostate Cancer

DTIC Science & Technology

2011-04-01

castrate resistant pros- tate cancer that initially undergoes a latency period (possibly quiescent low proliferating tumors as docu- mented in the...our results demonstrate that low dose concurrent panobinostat/everolimus combination therapy is well tolerated and results in greater anti-tumor...and dose dependent manner, where as Myc-CaP cell lines were resistant to the cytotoxic effects of everolimus. Treatment with low dose (non

Astaxanthin Inhibits Proliferation of Human Gastric Cancer Cell Lines by Interrupting Cell Cycle Progression.

PubMed

Kim, Jung Ha; Park, Jong-Jae; Lee, Beom Jae; Joo, Moon Kyung; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

2016-05-23

Astaxanthin is a carotenoid pigment that has antioxidant, antitumoral, and anti-inflammatory properties. In this in vitro study, we investigated the mechanism of anticancer effects of astaxanthin in gastric carcinoma cell lines. The human gastric adenocarcinoma cell lines AGS, KATO-III, MKN-45, and SNU-1 were treated with various concentrations of astaxanthin. A cell viability test, cell cycle analysis, and immunoblotting were performed. The viability of each cancer cell line was suppressed by astaxanthin in a dose-dependent manner with significantly decreased proliferation in KATO-III and SNU-1 cells. Astaxanthin increased the number of cells in the G0/G1 phase but reduced the proportion of S phase KATO-III and SNU-1 cells. Phosphorylated extracellular signal-regulated kinase (ERK) was decreased in an inverse dose-dependent correlation with astaxanthin concentration, and the expression of p27(kip-1) increased the KATO-III and SNU-1 cell lines in an astaxanthin dose-dependent manner. Astaxanthin inhibits proliferation by interrupting cell cycle progression in KATO-III and SNU-1 gastric cancer cells. This may be caused by the inhibition of the phosphorylation of ERK and the enhanced expression of p27(kip-1).

Agglucetin, a tetrameric C-type lectin-like venom protein, regulates endothelial cell survival and promotes angiogenesis by activating integrin {alpha}v{beta}3 signaling

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

Wang, W.-J.

2008-05-02

Agglucetin, a platelet glycoprotein (GP)Ib binding protein from Formosan Agkistrodon acutus (A. acutus) venom, could sustain human umbilical vein endothelial cell (HUVEC) proliferation and HUVEC adhering to immobilized agglucetin showed extensive spreading, which was strongly abrogated by integrin antagonists 7E3 and triflavin. Flow cytometric analyses confirmed the expression of GPIb complex on HUVEC is absent and fluorescein isothiocyanate (FITC)-agglucetin binds to HUVEC in a dose-dependent and saturable manner. Furthermore, native agglucetin specifically and dose-dependently inhibited the binding of FITC-23C6, an anti-{alpha}v{beta}3 monoclonal antibody (mAb), but not antibodies against {alpha}2 and {alpha}5, toward HUVEC and purified {alpha}v{beta}3 also bound to immobilizedmore » agglucetin-{beta} in a dose-dependent manner. Moreover, agglucetin exhibited a pro-angiogenic effect in vitro, as well as the focal adhesion kinase (FAK)-associated signaling molecules responsible for HUVEC activation were initiated by agglucetin. In conclusion, agglucetin, acting as a survival factor, promotes endothelial adhesion and angiogenesis by triggering {alpha}v{beta}3 signaling through FAK/phosphatidylinositol 3-kinase (PI3K)/Akt pathway.« less

Licochalcone-A Induces Intrinsic and Extrinsic Apoptosis via ERK1/2 and p38 Phosphorylation-mediated TRAIL Expression in Head and Neck Squamous Carcinoma FaDu Cells

PubMed Central

Park, Mi-Ra; Kim, Su-Gwan; Cho, In-A; Oh, Dahye; Kang, Kyeong-Rok; Lee, Sook-Young; Moon, Sung-Min; Cho, Seung Sik; Yoon, Goo; Kim, Chun Sung; Oh, Ji-Su; You, Jae-Seek; Kim, Do Kyung; Seo, Yo-Seob; Im, Hee-Jeong; Kim, Jae-Sung

2015-01-01

We investigated Licochalcone-A (Lico-A)-induced apoptosis and the pathway underlying its activity in a pharyngeal squamous carcinoma FaDu cell line. Lico-A purified from root of Glycyrrhiza inflata had cytotoxic effects, significantly increasing cell death in FaDu cells. Using a cell viability assay, we determined that the IC50 value of Lico-A in FaDu cells was approximately 100 µM. Chromatin condensation was observed in FaDu cells treated with Lico-A for 24 h. Consistent with this finding, the number of apoptotic cells increased in a time-dependent manner when FaDu cells were treated with Lico-A. TRAIL was significantly up-regulated in Lico-A-treated FaDu cells in a dose-dependent manner. Apoptotic factors such as caspases and PARP polymerase were subsequently activated in a caspase-dependent manner. In addition, levels of pro-apoptotic factors increased significantly in response to Lico-A treatment, while levels of anti-apoptotic factors decreased. Lico-A-induced TRAIL expression was mediated in part by a MAPK signaling pathway involving ERK1/2 and p38. Lastly, in an in vivo xenograft mouse model, Lico-A treatment effectively suppressed the growth of FaDu cell xenografts by activating caspase-3, without affecting the body weight of mice. Taken together, these data suggest that Lico-A has potential chemopreventive effects and should therefore be developed as a chemotherapeutic agent for pharyngeal squamous carcinoma. PMID:25572524

Skeletal response to corticosteroid deficiency and excess in growing male rats

NASA Technical Reports Server (NTRS)

Li, M.; Shen, Y.; Halloran, B. P.; Baumann, B. D.; Miller, K.; Wronski, T. J.

1996-01-01

The study was designed to investigate bone histomorphometric changes induced by corticosteroid deficiency and supplementation at different dose levels in the rat skeleton. Male rats were adrenalectomized (ADX) or sham-operated and divided into six groups. At 2 days after surgery, sham-operated control rats (CON + PLA) and one group of ADX rats (ADX + PLA) were implanted subcutaneously (s.c.) with placebo pellets. ADX rats in the remaining four groups (ADX + C25, ADX + C50, ADX + C100, and ADX + C300) were implanted sc with corticosterone pellets designed to release 25, 50, 100, or 300 mg of the hormone over a 60 day period. Each ADX rat was also implanted sc with an aldosterone pellet (2.5 mg) similarly designed to release its contents over the same time period. All rats were killed at 3 weeks after implantation of pellets. Terminal blood samples were collected for serum biochemistry and the proximal tibial metaphyses (PTM), tibial diaphyses, and first lumbar vertebrae (LV) were processed undecalcified for quantitative bone histomorphometry. A dose-dependent increase in serum corticosterone concentration was observed in ADX rats implanted with hormone pellets. In comparison to CON + PLA rats, ADX + PLA rats had lower cancellous bone volume associated with a stimulation in longitudinal bone growth, an increase in mineral apposition rate, and a trend for increased osteoclast and osteoblast surfaces in PTM. In contrast, cancellous bone of ADX + C25 rats was preserved at nearly the CON + PLA level. However, the higher doses of corticosterone increased cancellous bone mass, but decreased longitudinal bone growth and all indices of bone resorption and formation in a dose-dependent manner in PTM. Similar cancellous bone changes were observed in the LV of corticosterone-treated rats, with the exception of a lack of an hormonal effect on cancellous bone mass. In the tibial diaphysis, corticosterone inhibited periosteal bone formation in a dose-dependent manner, but did not affect cortical bone mass. The results indicate that corticosteroid deficiency induces cancellous osteopenia, whereas supplementation with a near physiologic dose of the hormone prevents this bone loss in ADX rats. Furthermore, corticosteroid excess inhibits bone growth and bone turnover in a dose-dependent manner, but does not induce cancellous osteopenia in growing male rats.

Dose-dependent effects of homologous seminal plasma on motility and kinematic characteristics of post-thaw stallion epididymal spermatozoa.

PubMed

Neuhauser, S; Dörfel, S; Handler, J

2015-05-01

Preservation of epididymal spermatozoa is important to save genetic material of endangered species and breeds, or in case of unexpected injury, which will end the breeding career of valuable sires. Seminal plasma (SP) influences sperm quality in a dose-dependent manner and its addition to preserved semen immediately before insemination may be beneficial for sperm fertility. Increased plasma membrane stability of epididymal spermatozoa reduces freezing injury of cells, and the addition of SP after freezing and thawing might have activating and protecting effects on spermatozoa within the female genital tract. In this study, epididymal spermatozoa were harvested by retrograde flush of the epididymal cauda immediately after routine castration and frozen. Seminal plasma was collected from other six stallions. Homologous SP (SP from the same species, but from a different animal) was added to frozen-thawed epididymal spermatozoa at concentrations of 0, 5, 20, 50 and 80% SP. Addition of SP increased sperm motility and influenced kinematic values in a dose-dependent manner (p < 0.05). Motility improved at concentrations of 20 and 50% SP, but did not further increase at 80% SP. There was no difference in sperm motility among SP from six different donor stallions regardless of the concentrations of SP (p > 0.05). Total and progressive motility of ten frozen-thawed epididymal spermatozoa samples collected from different stallions after dilution with extender and 5, 20, 50 or 80% SP differed significantly (p < 0.05). In conclusion, addition of homologous SP to frozen-thawed stallion epididymal spermatozoa immediately improved motility in a dose-dependent manner regardless of semen quality of SP donor stallions. This might positively influence fertility when SP is added before insemination. Moreover, there seems to be a threshold level of SP concentration for optimal improvement of sperm motility. © 2015 American Society of Andrology and European Academy of Andrology.

Hepatoprotective activity of Amaranthus spinosus in experimental animals.

PubMed

Zeashan, Hussain; Amresh, G; Singh, Satyawan; Rao, Chandana Venkateswara

2008-11-01

The hepatoprotective and antioxidant activity of 50% ethanolic extract of whole plant of Amaranthus spinosus (ASE) was evaluated against carbon tetrachloride (CCl4) induced hepatic damage in rats. The ASE at dose of 100, 200 and 400 mg/kg were administered orally once daily for fourteen days. The substantially elevated serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (SALP) and total bilirubin were restored towards normalization significantly by the ASE in a dose dependent manner. Higher dose exhibited significant hepatoprotective activity against carbon tetrachloride induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, in vivo antioxidant activities as malondialdehyde (MDA), hydroperoxides, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were also screened which were also found significantly positive in a dose dependent manner. The results of this study strongly indicate that whole plants of A. spinosus have potent hepatoprotective activity against carbon tetrachloride induced hepatic damage in experimental animals. This study suggests that possible mechanism of this activity may be due to the presence of flavonoids and phenolics compound in the ASE which may be responsible to hepatoprotective activity.

Diuretic effects of medetomidine compared with xylazine in healthy dogs.

PubMed

Talukder, Md Hasanuzzaman; Hikasa, Yoshiaki

2009-07-01

This study aimed to investigate and compare the effects of medetomidine and xylazine on diuretic and hormonal variables in healthy dogs. Five dogs, used in each of 11 groups, were injected intramuscularly with physiological saline solution (control), 5, 10, 20, 40, and 80 microg/kg of medetomidine, and 0.25, 0.5, 1, 2, and 4 mg/kg of xylazine. Urine and blood samples were taken 11 times over 24 h. Both medetomidine and xylazine increased urine production in a dose-dependent manner up to 4 h after injection, but the increase was much less with medetomidine than with xylazine at the tested doses. Urine specific gravity, pH, osmolality, and concentrations of creatinine, sodium, potassium, chloride, and arginine vasopressin (AVP) were decreased in a dose-dependent manner with both medetomidine and xylazine. Plasma osmolality and concentrations of sodium, potassium, and chloride were increased significantly with both drugs. Total amounts of urine AVP excreted and plasma AVP concentrations were significantly decreased by higher doses of medetomidine but were not significantly decreased by xylazine. Higher doses of both drugs significantly increased the plasma concentration of atrial natriuretic peptide (ANP), but the effect was greater with medetomidine than with xylazine. The results revealed that both drugs induce a profound diuresis, but medetomidine's effect is less dose-dependent than xylazine's effect. Although changes in plasma concentrations of AVP and ANP may partially influence the diuresis induced by medetomidine, other factors may be involved in the mechanism of the diuretic response to both drugs. Thus, both agents can be used clinically for transient but effective diuresis accompanied by sedation.

Effects of sub-acute methanol extract treatment of Calliandra portoricensis root bark on antioxidant defence capacity in an experimental rat model.

PubMed

Siemuri, Ese O; Akintunde, Jacob K; Salemcity, Anuoluwapo J

2015-07-01

The attendant side effects associated with some synthetic drugs used in the management of diseases have led to the search for safer alternative therapies that are relatively cheaper with minimal side effects. The methanol extract of Calliandra portoricensis root bark (CPRB) was orally administered at the doses of 5, 10, 20, and 25 mg/kg body weight for 14 consecutive days of 5 rats in each group. The control rats were given distilled water. The 95% methanol extract of CPRB significantly (p<0.05) scavenged NO• and OH• radicals compared to vitamin C. The level of lipid peroxidative products (malondialdehyde, MDA) was significantly (p<0.05) attenuated in a dose-dependent manner. Antioxidant enzymes including superoxide dismutase and catalase were significantly (p<0.05) exercabated in both liver and kidney in a dose-dependent manner. Furthermore, serum AST, alanine aminotransaminase and γ-glutamyltransferase (GGT) activity depicted non-significant (p>0.05) increase in the treated animals. The histological examination showed mild vacuolar, portal congestion and cell infiltration by mononuclear of the hepatic tissues. The study then concluded that a therapeutic dose of the methanol extract of CPRB triggered the antioxidant defence systems in male rats. It is, therefore, recommended that the doses should be carefully and clinically chosen because higher doses may cause some health risks.

Free radical scavenging, antidiarrheal and anthelmintic activity of Pistia stratiotes L. extracts and its phytochemical analysis.

PubMed

Bin Karim, Mohammed Faisal; Imam, Hasan; Sarker, Md Moklesur-Rahman; Uddin, Nizam; Hasan, Nahid; Paul, Nirmala; Haque, Tahmina

2015-05-01

In this phyto-pharmacological screening of Pistia stratiotes L leaf and root extracts each separately in two different solvents demonstrated its potential medicinal value. Apparent antioxidant value is demonstrated by DPPH, Nitric oxide scavenging and Ferric ion reducing method. Additionally, total flavonoid and phenolic compounds were measured. The leaf methanolic extract scavenged both nitric oxide (NO) and DPPH radical with a dose dependent manner. But the pet ether fraction of root was found to have highest efficacy in Fe(3±) reducing power assay. Flavonoid was found to contain highest in the pet ether fraction of root (411.35mg/g) in terms of quercetin equivalent, similarly highest amount (34.96mg/g) of total phenolic compounds (assayed as gallic acid equivalents) were found to contain in the same fraction. The methanolic fractions appeared less cytotoxic compared to pet ether extracts. The plant extracts caused a dose dependent decrease in faecal droppings in both castor oil and magnesium sulphate induced diarrhea, where as leaf extracts in each solvent appeared most effective. Also, the plant extracts showed anthelmintic activity in earthworm by inducing paralysis and death in a dose dependent manner. At highest doses (50 mg/ml) all fractions were almost effective as the positive control piperazine citrate (10 mg/ml). Thus, besides this cytotoxic effect it's traditional claim for therapeutic use can never be overlooked.

Maillard neoglycans as inhibitors for in vitro adhesion of F4+ enterotoxigenic Escherichia coli to piglet intestinal cells.

PubMed

Sarabia-Sainz, Héctor Manuel; Mata Haro, Verónica; Sarabia Sainz, José Andre-I; Vázquez-Moreno, Luz; Montfort, Gabriela Ramos-Clamont

2017-01-01

Adhesion of enterotoxigenic (ETEC) E. coli to host intestinal cells is mediated by lectin-like fimbriae that bind to specific glycan moieties on the surfaces of enterocytes. To prevent in vitro binding of E. coli F4 fimbriae (F4 ETEC + ) to piglet enterocytes, neoglycans were synthesized by the Maillard reaction conjugating lactose (Lac), galacto-oligosaccharides (GOS) or chitin oligosaccharides (Ochit) to porcine serum albumin (PSA). Neoglycans were characterized by SDS-PAGE, intrinsic tryptophan fluorescence and recognition by plant lectins, as well as by F4 ETEC variants. Electrophoretic patterns suggested the binding to PSA of 63, 13 and 2 molecules of Lac, GOS and Ochit, respectively. All neoglycans displayed quenching of tryptophan fluorescence consistent with the degree of glycation estimated by SDS-PAGE. Plant lectins recognized the neoglycans according to their specificity, whereas antigenic variants of F4 ETEC (ab, ac and ad) recognized PSA-Ochit and PSA-Lac with higher affinity than that for GOS. Neoglycans partially hindered the in vitro binding of F4 + ETEC to piglet enterocytes in a dose-dependent manner. The most effective blocking was observed with PSA-Lac that partially inhibited the adhesion of bacteria to enterocytes in a dose dependent manner, as quantified by flow cytometry. Increased production of the cytokines IL-6 and TNF-α was observed in response to F4 + ETEC infection of enterocytes and production was reduced in the presence of PSA-Ochit and PSA-GOS. These results suggest that neoglycans synthesized by the Maillard reaction could be useful in the prophylaxis of diarrhea in piglets.

Determinants of Propranolol's Selective Effect on Loss Aversion.

PubMed

Sokol-Hessner, Peter; Lackovic, Sandra F; Tobe, Russell H; Camerer, Colin F; Leventhal, Bennett L; Phelps, Elizabeth A

2015-07-01

Research on emotion and decision making has suggested that arousal mediates risky decisions, but several distinct and often confounded processes drive such choices. We used econometric modeling to separate and quantify the unique contributions of loss aversion, risk attitudes, and choice consistency to risky decision making. We administered the beta-blocker propranolol in a double-blind, placebo-controlled within-subjects study, targeting the neurohormonal basis of physiological arousal. Matching our intervention's pharmacological specificity with a quantitative model delineating decision-making components allowed us to identify the causal relationships between arousal and decision making that do and do not exist. Propranolol selectively reduced loss aversion in a baseline- and dose-dependent manner (i.e., as a function of initial loss aversion and body mass index), and did not affect risk attitudes or choice consistency. These findings provide evidence for a specific, modulatory, and causal relationship between precise components of emotion and risky decision making. © The Author(s) 2015.

Antibacterial Effect of Gallic Acid against Aeromonas hydrophila and Aeromonas sobria Through Damaging Membrane Integrity.

PubMed

Lu, Jing; Wang, Zhenning; Ren, Mengrou; Huang, Guoren; Fang, Baochen; Bu, Xiujuan; Liu, Yanhui; Guan, Shuang

In the study, we investigated the antibacterial activity and mechanism of gallic acid against Aeromonas hydrophila and Aeromonas sobria. Gallic acid showed strong antimicrobial activity against the two bacteria. Furthermore, the antibacterial mechanism of gallic acid (0, 3, 6, 12 mM) was performed by membrane integrity assay and scanning electron microscopy (SEM) assay. The results showed that gallic acid notably increased the released material absorption value at 260, 280 nm and electric conductivity in a dose-dependent manner. Moreover, the SEM assay showed that gallic acid induced severe shrink of bacterial intima and irregular morphology in a dose-dependent manner. The SDS-PAGE profiles further confirmed that gallic acid could damage bacterial cells. These results indicated gallic acid exhibited antibacterial effect by destroying membrane integrity of A. hydrophila and A. sobria. Hence, gallic acid has great potential as a new natural food preservative in food fresh-keeping and storage.

In vitro effects of 5-hydroxytryptophan, indoleamines and leptin on arylalkylamine N-acetyltransferase (AA-NAT) activity in pineal organ of the fish, Clarias gariepinus (Burchell, 1822) during different phases of the breeding cycle.

PubMed

Gupta, B B P; Yanthan, L; Singh, Ksh Manisana

2010-08-01

Arylalkylamine N-acetyltransferase (AA-NAT) is the rate-limiting enzyme of melatonin biosynthetic pathway. In vitro effects of 5-hydroxytryptophan (5-HTP) and indoleamines (serotonin, N-acetylserotonin and melatonin) were studied on AA-NAT activity in the pineal organ of the fish, C. gariepinus during different phases of its annual breeding cycle. Further, in vitro effects of leptin on AA-NAT activity in the pineal organ were studied in fed and fasted fishes during summer and winter seasons. Treatments with 5-HTP and indoleamines invariably stimulated pineal AA-NAT activity in a dose-dependent manner during all the phases. However, leptin increased AA-NAT activity in a dose-dependent manner only in the pineal organ of the fed fishes, but not of the fasted fishes irrespective of the seasons.

Dulaglutide (LY-2189265) for the treatment of type 2 diabetes.

PubMed

Scheen, André J

2016-01-01

Dulaglutide is a new once-weekly glucagon-like peptide-1 receptor agonist for the management of hyperglycemia in adult patients with type 2 diabetes. It stimulates dose-dependent insulin secretion and reduces glucagon secretion, both in a glucose-dependent manner. Efficacy on blood glucose control and safety were demonstrated in the large AWARD program in type 2 diabetic patients treated with diet, metformin, dual oral therapy or insulin lispro with or without metformin, confirming findings of pilot studies in Caucasian patients and data in Japanese patients. Dulaglutide 1.5 mg once weekly was superior to metformin, sitagliptin, insulin glargine and exenatide twice daily, and non-inferior to liraglutide 1.8 mg once daily regarding the reduction in glycated hemoglobin. A modest but significant weight loss was consistently observed. Most frequent adverse events were transient and generally mild gastrointestinal disturbances. Clinical outcomes of dulaglutide will not be known until the large prospective cardiovascular outcome trial REWIND is complete.

Phloretin Inhibits Platelet-derived Growth Factor-BB-induced Rat Aortic Smooth Muscle Cell Proliferation, Migration, and Neointimal Formation After Carotid Injury.

PubMed

Wang, Dong; Wang, Qingjie; Yan, Gaoliang; Qiao, Yong; Tang, Chengchun

2015-05-01

Abnormal vascular smooth muscle cell proliferation and migration are key factors in many cardiovascular diseases. Here, we investigated the effects of phloretin on platelet-derived growth factor homodimer (PDGF-BB)-induced rat aortic smooth muscle cell (RASMC) proliferation, migration, and neointimal formation after carotid injury. Phloretin significantly inhibited the PDGF-BB-stimulated RASMC proliferation in a concentration-dependent manner (10-100 μM). Also, PDGF-BB-stimulated RASMC migration was inhibited by phloretin at 50 μM. Pretreating RASMC with phloretin dose-dependently inhibited PDGF-BB-induced Akt and p38 mitogen-activated protein kinases activation. Furthermore, phloretin increased p27 and decreased cyclin-dependent kinase 2, CDK4 expression, and p-Rb activation in PDGF-BB-stimulated RASMC in a concentration-dependent manner (10-50 μM). PDGF-BB-induced cell adhesion molecules and matrix metalloproteinase-9 expression were blocked by phloretin at 50 μM. Preincubation with phloretin dose-dependently reduced the intracellular reactive oxygen species production. In vivo study showed that phloretin (20 mg/kg) significantly reduced neointimal formation 14 days after carotid injury in rats. Thus, phloretin may have potential as a treatment against atherosclerosis and restenosis after vascular injury.

Mutations in ash1 and trx enhance P-element-dependent silencing in Drosophila melanogaster.

PubMed

McCracken, Allen; Locke, John

2016-08-01

In Drosophila melanogaster, the mini-w(+) transgene in Pci is normally expressed throughout the adult eye; however, when other P or KP elements are present, a variegated-eye phenotype results, indicating random w(+) silencing during development called P-element-dependent silencing (PDS). Mutant Su(var)205 and Su(var)3-7 alleles act as haplo-suppressors/triplo-enhancers of this variegated phenotype, indicating that these heterochromatic modifiers act dose dependently in PDS. Previously, we recovered a spontaneous mutation of P{lacW}ci(Dplac) called P{lacW}ci(DplacE1) (E1) that variegated in the absence of P elements, presumably due to the insertion of an adjacent gypsy element. From a screen for genetic modifiers of E1 variegation, we describe here the isolation of five mutations in ash1 and three in trx that enhance the E1 variegated phenotype in a dose-dependent and cumulative manner. These mutant alleles enhance PDS at E1, and in E1/P{lacW}ci(Dplac), but suppress position effect variegation (PEV) at In(1)w(m)(4). This opposite action is consistent with a model where ASH1 and TRX mark transcriptionally active chromatin domains. If ASH1 or TRX function is lost or reduced, heterochromatin can spread into these domains creating a sink that diverts heterochromatic proteins from other variegating locations, which then may express a suppressed phenotype.

The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice

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

Hao, Chan-Juan; Cheng, Xue-Jia; Xia, Hong-Fei, E-mail: hongfeixia@yahoo.com.cn

Epidemiology studies indicate that exposure to endocrine disruptors during developmental “window” contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity.more » Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders. -- Highlights: ► DES induced adipocyte differentiation in a dose-dependent manner in 3T3-L1 cells. ► DES activated adipogenic critical regulators and markers in vitro and in vivo. ► Perinatal exposure to DES led to the obese phenotype in female offspring. ► DES might be a potential chemical stressor for obesity and obesity-related disorders.« less

Ecotoxicological evaluation of tributyltin toxicity to the equilateral venus clam, Gomphina veneriformis (Bivalvia: Veneridae).

PubMed

Park, Kiyun; Kim, Rosa; Park, Jung Jun; Shin, Hyun Chool; Lee, Jung Sick; Cho, Hyeon Seo; Lee, Yeon Gyu; Kim, Jongkyu; Kwak, Inn-Sil

2012-03-01

Tributyltin (TBT) is the most common pesticide in marine and freshwater environments. To evaluate the potential ecological risk posed by TBT, we measured biological responses such as growth rate, gonad index, sex ratio, the percentage of intersex gonads, filtration rate, and gill abnormalities in the equilateral venus clam (Gomphina veneriformis). Additionally, the biochemical and molecular responses were evaluated in G. veneriformis exposed to various concentrations of TBT. The growth of G. veneriformis was significantly delayed in a dose-dependent manner after exposure to all tested TBT concentrations. After TBT was administered to G. veneriformis, the gonad index decreased and the sex balance was altered. The percentage of intersex gonads also increased significantly in treated females, whereas no intersex gonads were detected in the solvent control group. Additionally, intersex gonads were detected in male G. veneriformis specimens exposed to relatively high TBT concentrations (20 μg L⁻¹). The filtration rate was also reduced in a dose-dependent manner in TBT-exposed G. veneriformis. We also noted abnormal gill morphology in TBT-exposed G. veneriformis. Furthermore, increases in antioxidant enzyme activities were observed in TBT-exposed G. veneriformis clams, regardless of dosage. Vitellogenin gene expression also increased significantly in a dose-dependent manner in G. veneriformis exposed to TBT. These results provide valuable information regarding our understanding of the toxicology of TBT in G. veneriformis. Moreover, the responses of biological and molecular factors could be utilized as information for risk assessments and marine monitoring of TBT toxicity. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Cytotoxic and apoptotic activities of black widow spiderling extract against HeLa cells

PubMed Central

Peng, Xiaozhen; Dai, Zhipan; Lei, Qian; Liang, Long; Yan, Shuai; Wang, Xianchun

2017-01-01

Black widow spiders contain toxic components not only in the venom glands but also in other parts of the spider body, including the legs and abdomen. Additionally, both the eggs and newborn spiderlings of the black widow spider contain venom. It is important to investigate their potential effects on cancer cells. In the present study, the effects of newborn black widow spiderling extract on human HeLa cells were evaluated in vitro. When applied at different concentrations, the total extract decreased HeLa cell viability in a dose-dependent manner, with an IC50 value of 158 µg/ml. Flow cytometry indicated that treatment of HeLa cells with the total extract of the spiderlings induced apoptosis in HeLa cells in a dose-dependent manner and led to cell cycle arrest in the S-phase. Additionally, application of the total extract at different concentrations increased apoptosis-related caspase 3 activity in a dose-dependent manner. HeLa cells treated with the total extract appeared to be morphologically changed, exhibiting membrane blebbing, nuclear fragmentation and condensation of chromatin. Further separation and activity screening demonstrated that the cytotoxic and apoptotic activities of the total extract were attributable mainly to its high molecular mass proteins, one of which was purified and characterized to determine its anti-tumor activities on HeLa cells. The results of the present study therefore have expanded understanding regarding the effect of spider toxins on cancer cells and suggested that components of black widow spiderlings may be developed as a promising novel agent to treat cancer. PMID:28587399

Cytotoxic and apoptotic activities of black widow spiderling extract against HeLa cells.

PubMed

Peng, Xiaozhen; Dai, Zhipan; Lei, Qian; Liang, Long; Yan, Shuai; Wang, Xianchun

2017-06-01

Black widow spiders contain toxic components not only in the venom glands but also in other parts of the spider body, including the legs and abdomen. Additionally, both the eggs and newborn spiderlings of the black widow spider contain venom. It is important to investigate their potential effects on cancer cells. In the present study, the effects of newborn black widow spiderling extract on human HeLa cells were evaluated in vitro . When applied at different concentrations, the total extract decreased HeLa cell viability in a dose-dependent manner, with an IC 50 value of 158 µg/ml. Flow cytometry indicated that treatment of HeLa cells with the total extract of the spiderlings induced apoptosis in HeLa cells in a dose-dependent manner and led to cell cycle arrest in the S-phase. Additionally, application of the total extract at different concentrations increased apoptosis-related caspase 3 activity in a dose-dependent manner. HeLa cells treated with the total extract appeared to be morphologically changed, exhibiting membrane blebbing, nuclear fragmentation and condensation of chromatin. Further separation and activity screening demonstrated that the cytotoxic and apoptotic activities of the total extract were attributable mainly to its high molecular mass proteins, one of which was purified and characterized to determine its anti-tumor activities on HeLa cells. The results of the present study therefore have expanded understanding regarding the effect of spider toxins on cancer cells and suggested that components of black widow spiderlings may be developed as a promising novel agent to treat cancer.

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

PubMed

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

2016-06-01

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

Astaxanthin Inhibits Proliferation of Human Gastric Cancer Cell Lines by Interrupting Cell Cycle Progression

PubMed Central

Kim, Jung Ha; Park, Jong-Jae; Lee, Beom Jae; Joo, Moon Kyung; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

2016-01-01

Background/Aims Astaxanthin is a carotenoid pigment that has antioxidant, antitumoral, and anti-inflammatory properties. In this in vitro study, we investigated the mechanism of anticancer effects of astaxanthin in gastric carcinoma cell lines. Methods The human gastric adenocarcinoma cell lines AGS, KATO-III, MKN-45, and SNU-1 were treated with various concentrations of astaxanthin. A cell viability test, cell cycle analysis, and immunoblotting were performed. Results The viability of each cancer cell line was suppressed by astaxanthin in a dose-dependent manner with significantly decreased proliferation in KATO-III and SNU-1 cells. Astaxanthin increased the number of cells in the G0/G1 phase but reduced the proportion of S phase KATO-III and SNU-1 cells. Phosphorylated extracellular signal-regulated kinase (ERK) was decreased in an inverse dose-dependent correlation with astaxanthin concentration, and the expression of p27kip-1 increased the KATO-III and SNU-1 cell lines in an astaxanthin dose-dependent manner. Conclusions Astaxanthin inhibits proliferation by interrupting cell cycle progression in KATO-III and SNU-1 gastric cancer cells. This may be caused by the inhibition of the phosphorylation of ERK and the enhanced expression of p27kip-1. PMID:26470770

Formononetin suppresses the proliferation of human non-small cell lung cancer through induction of cell cycle arrest and apoptosis.

PubMed

Yang, Yi; Zhao, Yi; Ai, Xinghao; Cheng, Baijun; Lu, Shun

2014-01-01

Formononetin is a novel herbal isoflavonoid isolated from Astragalus membranaceus and possesses antitumorigenic properties. In the present study, we investigated the anti-proliferative effects of formononetin on human non-small cell lung cancer (NSCLC), and further elucidated the molecular mechanism underlying the anti-tumor property. MTT assay showed that formononetin treatment significantly inhibited the proliferation of two NSCLC cell lines including A549 and NCI-H23 in a time- and dose-dependent manner. Flow cytometric analysis demonstrated that formononetin induced G1-phase cell cycle arrest and promoted cell apoptosis in NSCLC cells. On the molecular level, we observed that exposure to formononetin altered the expression levels of cell cycle arrest-associated proteins p21, cyclin A and cyclin D1. Meanwhile, the apoptosis-related proteins cleaved caspase-3, bax and bcl-2 were also changed following treatment with formononetin. In addition, the expression level of p53 was dose-dependently upregulated after administration with formononetin. We also found that formononetin treatment increased the phosphorylation of p53 at Ser15 and Ser20 and enhances its transcriptional activity in a dose-dependent manner. Collectively, these results demonstrated that formononetin might be a potential chemopreventive drug for lung cancer therapy through induction of cell cycle arrest and apoptosis in NSCLC cells.

The safety of green tea and green tea extract consumption in adults - Results of a systematic review.

PubMed

Hu, Jiang; Webster, Donna; Cao, Joyce; Shao, Andrew

2018-06-01

A systematic review of published toxicology and human intervention studies was performed to characterize potential hazards associated with consumption of green tea and its preparations. A review of toxicological evidence from laboratory studies revealed the liver as the target organ and hepatotoxicity as the critical effect, which was strongly associated with certain dosing conditions (e.g. bolus dose via gavage, fasting), and positively correlated with total catechin and epigallocatechingallate (EGCG) content. A review of adverse event (AE) data from 159 human intervention studies yielded findings consistent with toxicological evidence in that a limited range of concentrated, catechin-rich green tea preparations resulted in hepatic AEs in a dose-dependent manner when ingested in large bolus doses, but not when consumed as brewed tea or extracts in beverages or as part of food. Toxico- and pharmacokinetic evidence further suggests internal dose of catechins is a key determinant in the occurrence and severity of hepatotoxicity. A safe intake level of 338 mg EGCG/day for adults was derived from toxicological and human safety data for tea preparations ingested as a solid bolus dose. An Observed Safe Level (OSL) of 704 mg EGCG/day might be considered for tea preparations in beverage form based on human AE data. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Repeat dose NRPT (nicotinamide riboside and pterostilbene) increases NAD+ levels in humans safely and sustainably: a randomized, double-blind, placebo-controlled study.

PubMed

Dellinger, Ryan W; Santos, Santiago Roel; Morris, Mark; Evans, Mal; Alminana, Dan; Guarente, Leonard; Marcotulli, Eric

2017-01-01

NRPT is a combination of nicotinamide riboside (NR), a nicotinamide adenine dinucleotide (NAD +) precursor vitamin found in milk, and pterostilbene (PT), a polyphenol found in blueberries. Here, we report this first-in-humans clinical trial designed to assess the safety and efficacy of a repeat dose of NRPT (commercially known as Basis). NRPT was evaluated in a randomized, double-blind, and placebo-controlled study in a population of 120 healthy adults between the ages of 60 and 80 years. The study consisted of three treatment arms: placebo, recommended dose of NRPT (NRPT 1X), and double dose of NRPT (NRPT 2X). All subjects took their blinded supplement daily for eight weeks. Analysis of NAD + in whole blood demonstrated that NRPT significantly increases the concentration of NAD + in a dose-dependent manner. NAD + levels increased by approximately 40% in the NRPT 1X group and approximately 90% in the NRPT 2X group after 4 weeks as compared to placebo and baseline. Furthermore, this significant increase in NAD + levels was sustained throughout the entire 8-week trial. NAD + levels did not increase for the placebo group during the trial. No serious adverse events were reported in this study. This study shows that a repeat dose of NRPT is a safe and effective way to increase NAD + levels sustainably.

Antioxidant and anticancer activity of Artemisia princeps var. orientalis extract in HepG2 and Hep3B hepatocellular carcinoma cells.

PubMed

Choi, Eun-Jeong; Kim, Gun-Hee

2013-10-01

The aim of the present study was to investigate antioxidant and the anticancerigen activity of a methanol extract from Artemisia princeps var. orientalis (APME), a well-known traditional herbal medicine in Asia, in hepatocellular cancer cells. To evaluate the antioxidant activity of APME, reactive oxygen species (ROS) and the antioxidant enzymes, superoxide dismutase (SOD) and catalase were investigated in HepG2 cells exposed to APME (5, 100, and 200 µg/mL) for 72 h. Then, to evaluate the anticancer activity of APME, we investigated the proliferation and apoptosis induction of HepG2 and Hep3B cells exposed to APME (1-200 µg/mL) for 24, 48, and 72 h. APME dose-dependently reduced the generation of ROS in the presence of H2O2 compared with control cells. Furthermore, it increased catalase and SOD activity. Moreover, APME inhibited cell proliferation in a dose- and time-dependent manner, but at concentrations lower than 100 µg/mL, the inhibition was less dose-dependent than time-dependent. HepG2 and Hep3B cells exposed to 5, 100, and 200 µg/mL APME for 72 h underwent cell cycle arrest and apoptosis. Exposure to APME resulted in a significant increase in the number of cells in G1 phase and a decrease in the G2/M phase cell population. In addition, APME induced P53 expression of HepG2 cells in a dose-dependent manner, and played a role in the downregulation of Bcl-2 and upregulation of Bax in both HepG2 and Hep3B cells. These results indicate the potential role of APME as an antioxidant and anticancerigen agent in hepatocarcinoma cell lines.

Dose and dose rate effects of whole-body proton-irradiation on lymphocyte blastogenesis and hematological variables: part II

NASA Technical Reports Server (NTRS)

Pecaut, Michael J.; Gridley, Daila S.; Smith, Anna L.; Nelson, Gregory A.

2002-01-01

The goal of part II of this study was to evaluate functional characteristics of leukocytes and circulating blood cell parameters after whole-body proton irradiation at varying doses and at low- and high-dose-rates (LDR and HDR, respectively). C57BL/6 mice (n=51) were irradiated and euthanized at 4 days post-exposure for assay. Significant radiation dose- (but not dose-rate-) dependent decreases were observed in splenocyte responses to T and B cell mitogens when compared to sham-irradiated controls (P<0.001). Spontaneous blastogenesis, also significantly dose-dependent, was increased in both blood and spleen (P<0.001). Red blood cell counts, hemoglobin concentration, and hematocrit were decreased in a dose-dependent manner (P<0.05), whereas thrombocyte numbers were only slightly affected. Comparison of proton- and gamma-irradiated groups (both receiving 3 Gy at HDR) showed a higher level of spontaneous blastogenesis in blood leukocytes and a lower splenocyte response to concanavalin A following proton irradiation (P<0.05). There were no dose rate effects. Collectively, the data demonstrate that the measurements in blood and spleen were largely dependent upon the total dose of proton radiation and that an 80-fold difference in the dose rate was not a significant factor. A difference, however, was found between protons and gamma-rays in the degree of change induced in some of the measurements.

Evaluation of immunomodulatory activity of methanolic extract of Piper betel.

PubMed

Kanjwani, D G; Marathe, T P; Chiplunkar, S V; Sathaye, S S

2008-06-01

Many of the disorders today are based on the imbalances of immunological processes. This necessitates the search for newer and safer immunomodulators. Thus, the objective of the present study was to explore the immunomodulatory activity of the methanolic extract of Piper betel L. (MPb) (Family: Piperaceae). The MPb consists of mixture of phenols, flavonoids, tannins and polysaccharides. Both in vitro as well as in vivo evaluation was carried out. The effects of MPb on lymphocyte proliferation, interferon-gamma receptors and the production of nitric oxide were measured in vitro. Further, the extract at different dose levels was studied in vivo for the humoral and cellular immune responses on mice immunized with sheep red blood cells. P. betel significantly suppressed phytohaemagglutinin stimulated peripheral blood lymphocyte proliferation in a dose-dependent manner. The decrease in antibody titre and increased suppression of inflammation suggests possible immunosuppressive effect of extract on cellular and humoral response in mice. Thus, the MPb could be explored extensively as a therapeutic agent to treat various immune disorders including autoimmune disorders.

Age-dependent effects of initial exposure to nicotine on serotonin neurons.

PubMed

Bang, S J; Commons, K G

2011-04-14

Adolescence is a critical vulnerable period during which exposure to nicotine greatly enhances the possibility to develop drug addiction. Growing evidence suggests that serotonergic (5-HT) neurotransmission may contribute to the initiation and maintenance of addictive behavior. As the dorsal raphe (DR) and median raphe (MnR) nuclei are the primary 5-HT source to the forebrain, the current study tested the hypothesis that there are age-dependent effects of acute nicotine administration on activation of 5-HT neurons within these regions. Both adolescent (Postnatal day 30) and adult (Postnatal day 70) male Sprague-Dawley rats received subcutaneous injection of either saline or nicotine (0.2, 0.4, or 0.8 mg/kg). Subsequently, the number of 5-HT cells that were double-labeled for Fos and tryptophan hydroxylase was counted in seven subregions within the DR and the entire MnR. The results show that acute nicotine injection induces Fos expression in 5-HT neurons in a region-specific manner. In addition, adolescents show broader regional activations at either a lower (0.2 mg/kg) and a higher (0.8 mg/kg) dose of nicotine, displaying a unique U-shape response curve across doses. In contrast, 5-HT cells with activated Fos expression were restricted to fewer regions in adults, and the patterns of expression were more consistent across doses. The results reveal dose-dependent effects of nicotine during adolescence with apparent sensitization at different ends of the dosage spectrum examined compared to adults. These data indicate that initial exposure to nicotine may have unique effects in adolescence on the ascending 5-HT system, with the potential for consequences on the affective-motivational qualities of the drug and the subsequent propensity for repeated use. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Age-Dependent Effects of Initial Exposure to Nicotine on Serotonin Neurons

PubMed Central

Bang, Sun Jung; Commons, Kathryn G.

2011-01-01

Adolescence is a critical vulnerable period during which exposure to nicotine greatly enhances the possibility to develop drug addiction. Growing evidence suggests that serotonergic (5-HT) neurotransmission may contribute to the initiation and maintenance of addictive behavior. As the dorsal raphe (DR) and median raphe (MnR) nuclei are the primary 5-HT source to the forebrain, the current study tested the hypothesis that there are age-dependent effects of acute nicotine administration on activation of 5-HT neurons within these regions. Both adolescent (Postnatal day 30) and adult (Postnatal day 70) male Sprague-Dawley rats received subcutaneous injection of either saline or nicotine (0.2, 0.4, or 0.8 mg/kg). Subsequently, the number of 5-HT cells that were double-labeled for Fos and tryptophan hydroxylase was counted in 7 subregions within the DR and the entire MnR. The results show that acute nicotine injection induces Fos expression in 5-HT neurons in a region-specific manner. In addition, adolescents show broader regional activations at either a lower (0.2 mg/kg) and a higher (0.8 mg/kg) dose of nicotine, displaying a unique U-shape response curve across doses. In contrast, 5-HT cells with activated Fos expression were restricted to fewer regions in adults, and the patterns of expression were more consistent across doses. The results reveal dose-dependent effects of nicotine during adolescence with apparent sensitization at different ends of the dosage spectrum examined compared to adults. These data indicate that initial exposure to nicotine may have unique effects in adolescence on the ascending 5-HT system, with the potential for consequences on the affective-motivational qualities of the drug and the subsequent propensity for repeated use. PMID:21277949

Diuretic effects of medetomidine compared with xylazine in healthy dogs

PubMed Central

Talukder, Md. Hasanuzzaman; Hikasa, Yoshiaki

2009-01-01

This study aimed to investigate and compare the effects of medetomidine and xylazine on diuretic and hormonal variables in healthy dogs. Five dogs, used in each of 11 groups, were injected intramuscularly with physiological saline solution (control), 5, 10, 20, 40, and 80 μg/kg of medetomidine, and 0.25, 0.5, 1, 2, and 4 mg/kg of xylazine. Urine and blood samples were taken 11 times over 24 h. Both medetomidine and xylazine increased urine production in a dose-dependent manner up to 4 h after injection, but the increase was much less with medetomidine than with xylazine at the tested doses. Urine specific gravity, pH, osmolality, and concentrations of creatinine, sodium, potassium, chloride, and arginine vasopressin (AVP) were decreased in a dose-dependent manner with both medetomidine and xylazine. Plasma osmolality and concentrations of sodium, potassium, and chloride were increased significantly with both drugs. Total amounts of urine AVP excreted and plasma AVP concentrations were significantly decreased by higher doses of medetomidine but were not significantly decreased by xylazine. Higher doses of both drugs significantly increased the plasma concentration of atrial natriuretic peptide (ANP), but the effect was greater with medetomidine than with xylazine. The results revealed that both drugs induce a profound diuresis, but medetomidine’s effect is less dose-dependent than xylazine’s effect. Although changes in plasma concentrations of AVP and ANP may partially influence the diuresis induced by medetomidine, other factors may be involved in the mechanism of the diuretic response to both drugs. Thus, both agents can be used clinically for transient but effective diuresis accompanied by sedation. PMID:19794896

In vitro immunomodulatory effects of cuphiin D1 on human mononuclear cells.

PubMed

Wang, Ching-Chiung; Chen, Lih-Geeng; Yang, Ling-Ling

2002-01-01

Cuphiin D1 (CD1), a macrocyclic hydrolyzable tannin isolated from Cuphea hyssopifolia, has been shown to exert antitumor activity both in vitro and in vivo. Moreover, the antitumor effects of CD1 are not only related to its cytotoxicity to carcinoma cell lines, but also depend on host-mediated mechanisms. In the present study, CD1 was investigated for its effects on the proliferation and cytokine secretion of human peripheral blood mononuclear cells (PBMCs). At concentrations of from 6.25 to 50 micrograms/ml, it enhanced the 3H-thymidine incorporation of concanavalin A (Con A)-stimulated PBMCs in a dose-dependent manner. Excretion of IL-1 beta, IL-2 and TNF-alpha by CD1-stimulated PBMCs was markedly increased in a dose-dependent manner. The results show that CD1 could stimulate PBMCs release of IL-1 beta, IL-2 and TNF-alpha and then activate T cells. Therefore, CD1-activated T cells via IL-1 beta in vitro might account for the host-mediated CD1 mechanism of action.

[Inhibitive effect of matrine modification X on the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice].

PubMed

Shi, Shujing; Tang, Anzhou; Yin, Shaolin; Wang, Lisheng; Xie, Mao; Yi, Xiang

2014-11-01

To evaluate the inhibitive effect of matrine modification X on the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice. Tumor model was established by subcutaneous inoculation of nasopharyngeal carcinoma cell CNE2 into nude mice, which was used to evaluate the antitumor effect of matrine modification X in vivo. The expression levels of Bax, Bcl-2, Caspase3 were detected by real-time PCR and western blot. The growth of xenografts in nude mice was significantly suppressed after application of matrine modification X in a dose-dependent manner. The inhibition rates were 32.55% and 44.89% when treated at medium and high dose respectively. Real-time fluorescence quantitative-PCR and Western Blot results showed that the expression of Bax and Caspase3 increased, while the expression of Bcl-2 decreased in a dose-dependent manner. The change of high dose group was obvious, and the difference was statistically significant (P < 0.05). Matrine modification X could significantly inhibit the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice, probably by inducing the apoptosis of nasopharyngeal carcinoma cells, and the possible mechanism is related to regulating the expression level of Bax/Bcl-2 and Casepase3.

Dietary proanthocyanidins boost hepatic NAD(+) metabolism and SIRT1 expression and activity in a dose-dependent manner in healthy rats.

PubMed

Aragonès, Gerard; Suárez, Manuel; Ardid-Ruiz, Andrea; Vinaixa, Maria; Rodríguez, Miguel A; Correig, Xavier; Arola, Lluís; Bladé, Cinta

2016-04-22

Proanthocyanidins (PACs) have been reported to modulate multiple targets by simultaneously controlling many pivotal metabolic pathways in the liver. However, the precise mechanism of PAC action on the regulation of the genes that control hepatic metabolism remains to be clarified. Accordingly, we used a metabolomic approach combining both nuclear magnetic resonance and mass spectrometry analysis to evaluate the changes induced by different doses of grape-seed PACs in the liver of healthy rats. Here, we report that PACs significantly increased the hepatic nicotinamide adenine dinucleotide (NAD(+)) content in a dose-dependent manner by specifically modulating the hepatic concentrations of the major NAD(+) precursors as well as the mRNA levels of the genes that encode the enzymes involved in the cellular metabolism of NAD(+). Notably, Sirtuin 1 (Sirt1) gene expression was also significantly up-regulated in a dose-response pattern. The increase in both the NAD(+) availability and Sirt1 mRNA levels, in turn, resulted in the hepatic activation of SIRT1, which was significantly associated with improved protection against hepatic triglyceride accumulation. Our data clearly indicates that PAC consumption could be a valid tool to enhance hepatic SIRT1 activity through the modulation of NAD(+) levels.

Dietary proanthocyanidins boost hepatic NAD+ metabolism and SIRT1 expression and activity in a dose-dependent manner in healthy rats

PubMed Central

Aragonès, Gerard; Suárez, Manuel; Ardid-Ruiz, Andrea; Vinaixa, Maria; Rodríguez, Miguel A.; Correig, Xavier; Arola, Lluís; Bladé, Cinta

2016-01-01

Proanthocyanidins (PACs) have been reported to modulate multiple targets by simultaneously controlling many pivotal metabolic pathways in the liver. However, the precise mechanism of PAC action on the regulation of the genes that control hepatic metabolism remains to be clarified. Accordingly, we used a metabolomic approach combining both nuclear magnetic resonance and mass spectrometry analysis to evaluate the changes induced by different doses of grape-seed PACs in the liver of healthy rats. Here, we report that PACs significantly increased the hepatic nicotinamide adenine dinucleotide (NAD+) content in a dose-dependent manner by specifically modulating the hepatic concentrations of the major NAD+ precursors as well as the mRNA levels of the genes that encode the enzymes involved in the cellular metabolism of NAD+. Notably, Sirtuin 1 (Sirt1) gene expression was also significantly up-regulated in a dose-response pattern. The increase in both the NAD+ availability and Sirt1 mRNA levels, in turn, resulted in the hepatic activation of SIRT1, which was significantly associated with improved protection against hepatic triglyceride accumulation. Our data clearly indicates that PAC consumption could be a valid tool to enhance hepatic SIRT1 activity through the modulation of NAD+ levels. PMID:27102823

Immunostimulative Activity of Low Molecular Weight Chitosans in RAW264.7 Macrophages

PubMed Central

Wu, Ning; Wen, Zheng-Shun; Xiang, Xing-Wei; Huang, Yan-Na; Gao, Yang; Qu, You-Le

2015-01-01

Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been reported to exert many biological activities, such as antioxidant and antitumor effects. However, complex and molecular weight dependent effects of chitosan remain controversial and the mechanisms that mediate these complex effects are still poorly defined. This study was carried out to investigate the immunostimulative effect of different molecular weight chitosan in RAW264.7 macrophages. Our data suggested that two LMWCs (molecular weight of 3 kDa and 50 kDa) both possessed immunostimulative activity, which was dependent on dose and, at the higher doses, also on the molecular weight. LMWCs could significantly enhance the the pinocytic activity, and induce the production of tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), interferon-γ (IFN-γ), nitric oxide (NO) and inducible nitric oxide synthase (iNOS) in a molecular weight and concentration-dependent manner. LMWCs were further showed to promote the expression of the genes including iNOS, TNF-α. Taken together, our findings suggested that LMWCs elicited significantly immunomodulatory response through up-regulating mRNA expression of proinflammatory cytokines and activated RAW264.7 macrophage in a molecular weight- and concentration-dependent manner. PMID:26437419

Dose-dependent decrease in anti-oxidant capacity of whole blood after irradiation: A novel potential marker for biodosimetry.

PubMed

Sun, Lue; Inaba, Yohei; Sato, Keizo; Hirayama, Aki; Tsuboi, Koji; Okazaki, Ryuji; Chida, Koichi; Moritake, Takashi

2018-05-09

Many reports have demonstrated that radiation stimulates reactive oxygen species (ROS) production by mitochondria for a few hours to a few days after irradiation. However, these studies were performed using cell lines, and there is a lack of information about redox homeostasis in irradiated animals and humans. Blood redox homeostasis reflects the body condition well and can be used as a diagnostic marker. However, most redox homeostasis studies have focused on plasma or serum, and the anti-oxidant capacity of whole blood has scarcely been investigated. Here, we report changes in the anti-oxidant capacity of whole blood after X-ray irradiation using C57BL/6 J mice. Whole-blood anti-oxidant capacity was measured by electron spin resonance (ESR) spin trapping using a novel spin-trapping agent, 2-diphenylphosphinoyl-2-methyl-3,4-dihydro-2H-pyrrole N-oxide (DPhPMPO). We found that whole-blood anti-oxidant capacity decreased in a dose-dependent manner (correlation factor, r > 0.9; P < 0.05) from 2 to 24 days after irradiation with 0.5-3 Gy. We further found that the red blood cell (RBC) glutathione level decreased and lipid peroxidation level increased in a dose-dependent manner from 2 to 6 days after irradiation. These findings suggest that blood redox state may be a useful biomarker for estimating exposure doses during nuclear and/or radiation accidents.

New insights into the mechanism and actions of growth hormone (GH) in poultry.

PubMed

Vasilatos-Younken, R; Wang, X H; Zhou, Y; Day, J R; McMurtry, J P; Rosebrough, R W; Decuypere, E; Buys, N; Darras, V; Beard, J L; Tomas, F

1999-10-01

Despite well documented anabolic effects of GH in mammals, a clear demonstration of such responses in domestic poultry is lacking. Recently, comprehensive dose-response studies of GH have been conducted in broilers during late post-hatch development (8 to 9 weeks of age). GH reduced feed intake (FI) and body weight gain in a dose-dependent manner, whereas birds pair-fed to the level of voluntary FI of GH-infused birds did not differ from controls. The reduction in voluntary FI may involve centrally mediated mechanisms, as hypothalamic neuropeptide Y protein and mRNA were reduced with GH, coincident with the maximal depression in FI. Growth of breast muscle was also reduced in a dose-dependent manner. Circulating IGF-I was not enhanced by GH, despite evidence that early events in the GH signaling pathway were intact. A GH dose-dependent increase in circulating 3,3',5-triiodothyronine(T3) paralleled decreases in hepatic 5D-III monodeiodinase activity, whereas 5'D-I activity was not altered. This confirms that a marked hyperthyroid response to GH occurs in late posthatch chickens, resulting from a decrease in the degradative pathway of T3 metabolism. This secondary hyperthyroidism would account for the decreased skeletal muscle mass (52) and lack of enhanced IGF-I (53) in GH-treated birds. Based upon these studies, it is now evident that GH does in fact have significant effects in poultry, but metabolic responses may confound the anabolic potential of the hormone.

Evaluation of ammonium perchlorate in the endocrine disruptor screening and testing program's male pubertal protocol: ability to detect effects on thyroid endpoints.

PubMed

Stoker, T E; Ferrell, J M; Laws, S C; Cooper, R L; Buckalew, A

2006-11-10

The U.S. EPA Endocrine Disruptor Screening Program (EDSP) Tier 1 male pubertal protocol was designed as a screen to detect endocrine-disrupting chemicals which may alter reproductive development or thyroid function. One purpose of this in vivo screening protocol is to detect thyrotoxicants via a number of different mechanisms of action, such as thyroid hormone synthesis or clearance. Here we evaluate the ability of this EDSP male pubertal protocol to detect the known thyrotoxicant ammonium perchlorate as an endocrine disruptor. Ammonium perchlorate is a primary ingredient in rocket fuel, fertilizers, paints, and lubricants. Over the past 50 years, potassium perchlorate has been used to treat hyperthyroidism in humans. Perchlorate alters thyroid hormone secretion by competitively inhibiting iodide uptake by the thyroid gland. In this study, ammonium perchlorate was administered at 62.5, 125, 250, and 500 mg/kg to male Wistar rats based on a pilot study of oral dosing. Doses of 125-500 mg/kg perchlorate decreased T4 in a dose-dependent manner. TSH was significantly increased in a dose-responsive manner at the same doses, while T3 was unchanged at any dose. Thyroid histology was significantly altered at all doses, even at the 62.5 mg/kg, with a clear dose-dependent decrease in colloid area and increase in follicular cell height. No effects on preputial separation, a marker of pubertal progression, or reproductive tract development were observed at any dose. These results demonstrate that the male pubertal protocol is useful for detecting thyrotoxicants which target the thyroid axis by this mechanism (altered uptake of iodide). This study also found that perchlorate exposure during this period did not alter any of the reproductive developmental endpoints.

Time and dose-response effects of honokiol on UVB-induced skin cancer development.

PubMed

Guillermo, Ruth F; Chilampalli, Chandeshwari; Zhang, Xiaoying; Zeman, David; Fahmy, Hesham; Dwivedi, Chandradhar

2012-06-01

Honokiol has shown chemopreventive effects in chemically-induced and UVB-induced skin cancer in mice. In this investigation, we assessed the time-effects of a topical low dose of honokiol (30 μg), and then the effects of different honokiol doses (30, 45, and 60 μg) on a UVB-induced skin cancer model to find an optimal dose and time for desirable chemopreventive effects. UVB radiation (30 mJ/cm(2), 5 days/week for 25 or 27 weeks) was used to induce skin carcinogenesis in SKH-1 mice. For the time-response experiment 30 μg honokiol in acetone was applied topically to the animals before the UVB exposure (30 min, 1 h, and 2 h) and after the UVB exposure (immediately, 30 min, and 1 h). Control groups were treated with acetone. For the dose-response study, animals were treated topically with acetone or honokiol (30, 45, and 60 μg) one hour before the UVB exposure. In the time-response experiment, honokiol inhibited skin tumor multiplicity by 49-58% while reducing tumor volumes by 70-89%. In the dose-response study, honokiol (30, 45, and 60 μg) significantly decreased skin tumor multiplicity by 36-78% in a dose-dependent manner, while tumor area was reduced by 76-94%. Honokiol (60 μg) significantly reduced tumor incidence by 40% as compared to control group. Honokiol applied in very low doses (30 μg) either before or after UVB radiation shows chemopreventive effects. Honokiol (30, 45, and 60 μg) prevents UVB-induced skin cancer in a dose-dependent manner. Honokiol can be an effective chemopreventive agent against skin cancer.

Neuron-derived orphan receptor 1 promoted human pulmonary artery smooth muscle cells proliferation.

PubMed

Wang, Chang-Guo; Lei, Wei; Li, Chang; Zeng, Da-Xiong; Huang, Jian-An

2015-05-01

As a transcription factor of the nuclear receptor superfamily, neuron-derived orphan receptor 1 (NOR1) is induced rapidly in response to various extracellular stimuli. But, it is still unclear its role in pulmonary artery smooth muscle cells proliferation. Human PASMCs were cultured in vitro and stimulated by serum. The special antisense oligodeoxynucleotides (AS-ODNs) were used to knockdown human NOR1 gene expression. Real-time PCR and Western-blot were used to evaluate the gene expression and protein levels. Fetal bovine serum (FBS) induced human PASMCs proliferation in a dose dependent manner. Furthermore, FBS promoted NOR1 gene expression in a dose dependent manner and a time dependent manner. 10% FBS induced a maximal NOR1 mRNA levels at 2 h. FBS also induced a significant higher NOR1 protein levels as compared with control. The NOR1 over-expressed plasmid significantly promoted DNA synthesis and cells proliferation. Moreover, the special AS-ODNs against human NOR1 not only prevented NOR1 expression but also inhibited DNA synthesis and cells proliferation significantly. The NOR1 over-expression plasmid could up-regulate cyclin D1 expression markedly, but the AS-ODNs inhibited cyclin D1 expression significantly. So, we concluded that NOR1 could promote human PASMCs proliferation. Cyclin D1 might be involved in this process.

Quinine-induced tinnitus in rats.

PubMed

Jastreboff, P J; Brennan, J F; Sasaki, C T

1991-10-01

Quinine ingestion reportedly induces tinnitus in humans. To expand our salicylate-based animal model of tinnitus, a series of conditioned suppression experiments was performed on 54 male-pigmented rats using quinine injections to induce tinnitus. Quinine induced changes in both the extent of suppression and recovery of licking, which followed a pattern that paralleled those produced after salicylate injections, and which may be interpreted as the result of tinnitus perception in animals. These changes depended on the dose and time schedule of quinine administration. Additionally, the calcium channel blocker, nimodipine, abolished the quinine-induced effect in a dose-dependent manner.

[Apoptosis of multiple myeloid cells induced by polysaccharides extracts from Hedyotis diffusa and its mechanism].

PubMed

Lin, Sheng-yun; Shen, Chu-yun; Jiang, Jian-ping; Wu, Li-qiang; Dai, Tie-ying; Qian, Wen-bing; Meng, Hai-tao

2013-04-01

To explore the proliferation inhibition and apoptosis effects of polysaccharides extracts from Hedyotis diffusa (PEHD) on multiple myeloma (MM) cell line RPMI 8226 cells in vitro, so as to provide experimental theory for the clinical application in the treatment of MM. MTT assay was used to examine the effects of PEHD on cell growth. The apoptotic cells were analyzed by flow cytometry with AnnexinⅤ/PI staining. Hoechst staining was used to observe the morphological changes of RPMI 8226 cell apoptosis. The expression levels of caspase-3,-8,-9, PARP, nucleoprotein NF-κB protein and other channel protein were assayed by Western blotting method. The growth of RPMI 8226 cells were suppressed after treatment with PEHD, the highest inhibition rate reached to 92.3%, the results in the doses from 1 to 4 mg/ml showed a dose-and-time-dependent manner. The proportion of apoptotic cells in 1, 2 and 3 mg/ml PEHD treatment groups for 24 h were 22.52%, 62.31% and 69.94%, respectively, and significantly higher than that of control 8.93%. After treated with PEHD, apoptotic body appeared in RPMI 8226 cells nucleus and the number of apoptotic body increased in a dose-dependent manner. With the increasing of PEHD concentration, the expression of caspase-8,-9,-3 and PARP protein increased. The expression of Mcl-1, Bcl-xl, Bid and Bim protein decreased gradually, but the expression of Bax, Bak and Bad protein increased, and the expression of p-AKT protein (60 kDa) and NF-κB obviously decreased. PEHD could inhibited the growth of RPMI 8226 cells and displayed a dose-and-time-dependent manner, its mechanism may involve cell apoptosis induction, which was associated with the activation of caspase-8, caspase-9, and caspase-3 protein and the down-regulation of p-AKT and NF-κB protein expression.

Curcumin induces apoptosis and cell cycle arrest via the activation of reactive oxygen species-independent mitochondrial apoptotic pathway in Smad4 and p53 mutated colon adenocarcinoma HT29 cells.

PubMed

Agarwal, Ayushi; Kasinathan, Akiladdevi; Ganesan, Ramamoorthi; Balasubramanian, Akhila; Bhaskaran, Jahnavi; Suresh, Samyuktha; Srinivasan, Revanth; Aravind, K B; Sivalingam, Nageswaran

2018-03-01

Curcumin is a natural dietary polyphenol compound that has various pharmacological activities such as antiproliferative and cancer-preventive activities on tumor cells. Indeed, the role reactive oxygen species (ROS) generated by curcumin on cell death and cell proliferation inhibition in colon cancer is poorly understood. In the present study, we hypothesized that curcumin-induced ROS may promote apoptosis and cell cycle arrest in colon cancer. To test this hypothesis, the apoptosis-inducing potential and cell cycle inhibition effect of ROS induced by curcumin was investigated in Smd4 and p53 mutated HT-29 colon adenocarcinoma cells. We found that curcumin treatment significantly increased the level of ROS in HT-29 cells in a dose- and time-dependent manner. Furthermore, curcumin treatment markedly decreased the cell viability and proliferation potential of HT-29 cells in a dose- and time-dependent manner. Conversely, generation of ROS and inhibitory effect of curcumin on HT-29 cells were abrogated by N-acetylcysteine treatment. In addition, curcumin treatment did not show any cytotoxic effects on HT-29 cells. Furthermore, curcumin-induced ROS generation caused the DNA fragmentation, chromatin condensation, and cell nuclear shrinkage and significantly increased apoptotic cells in a dose- and time-dependent manner in HT-29 cells. However, pretreatment of N-acetylcysteine inhibited the apoptosis-triggering effect of curcumin-induced ROS in HT-29 cells. In addition, curcumin-induced ROS effectively mediated cell cycle inhibition in HT-29 cells. In conclusion, our data provide the first evidence that curcumin induces ROS independent apoptosis and cell cycle arrest in colon cancer cells that carry mutation on Smad4 and p53. Copyright © 2018. Published by Elsevier Inc.

Shikonin Inhibites Migration and Invasion of Thyroid Cancer Cells by Downregulating DNMT1

PubMed Central

Zhang, Yue; Sun, Bin; Huang, Zhi

2018-01-01

Background Shikonin is a component of Chinese herbal medicine. The aim of this study was to investigate the effects of shikonin on cell migration of papillary thyroid cancer cells of the TPC-1 cell line in vitro and expression levels of the phosphate and tensin homolog deleted on chromosome 10 (PTEN) and DNA methyltransferase 1 (DNMT1) genes. Material/Methods The Cell Counting Kit-8 (CCK-8) assay was performed to evaluate the proliferation of TPC-1 papillary thyroid cancer cells, and the normal thyroid cells, HTori-3, in vitro. A transwell motility assay was used to analyze the migration of TPC-1 cells. Western blot was performed to determine the expression levels of PTEN and DNMT1 genes. A methylation-specific polymerase chain reaction (PCR) (MSP) assay was used to evaluate the methylation of PTEN. Results Following treatment with shikonin, the cell survival rate of TPC-1 cells decreased in a dose-dependent manner; the inhibitory effects on HTori-3 cells were less marked. Shikonin inhibited TPC-1 cell migration and invasion in a dose-dependent manner. The methylation of PTEN was suppressed by shikonin, which also reduced the expression of DNMT1 in a dose-dependent manner, and increased the expression of PTEN. Overexpression of DNMT1 promoted the migration of TPC-1 cells and the methylation of PTEN. Levels of protein expression of PTEN in TPC-1 cells treated with shikonin decreased, and were increased by DNMT1 knockdown. Conclusions Shikonin suppressed the expression of DNMT1, reduced PTEN gene methylation, and increased PTEN protein expression, leading to the inhibition of TPC-1 cell migration. PMID:29389913

Dual effects of phloretin on aflatoxin B1 metabolism: activation and detoxification of aflatoxin B1.

PubMed

Gao, Shang Shang; Chen, Xiao Yan; Zhu, Ri Zhe; Choi, Byung-Min; Kim, Sun Jun; Kim, Bok-Ryang

2012-01-01

Typically, chemopreventive agents involve either induction of phase II detoxifying enzymes and/or inhibition of cytochrome P450 enzymes (CYPs) that are required for the activation of procarcinogens. In this study, we investigated the protective effects of phloretin against aflatoxin B1 (AFB1) activation to the ultimate carcinogenic intermediate, AFB(1)-8, 9-epoxide (AFBO), and its subsequent detoxification. Phloretin markedly inhibited formation of the epoxide with human liver microsomes in a dose-dependent manner. Phloretin also inhibited the activities of nifedipine oxidation and ethoxyresorufin O-deethylase (EROD) in human liver microsomes. These data show that phloretin strongly inhibits CYP1A2 and CYP3A4 activities, which are involved in the activation of AFB1. Phloretin increased glutathione S-transferase (GST) activity of alpha mouse liver 12 (AML 12) cells in a dose-dependent manner. GST activity toward AFBO in cell lysates treated with 20 μM phloretin was 23-fold that of untreated control cell lysates. The expression of GSTA3, GSTA4, GSTM1, GSTP1 and GSTT1 was induced by phloretin in a dose-dependent manner in AML 12 cells. GSTP1, GSTM1, and GSTT1 were able to significantly increase the conjugation of AFBO with glutathione. Concurrently, induction of the GST isozyme genes was partially associated with the Nrf2/ARE pathway. Taken together, the results demonstrate that phloretin has a strong chemopreventive effect against AFB1 through its inhibitory effect on CYP1A2, CYP3A4, and its inductive effect on GST activity. Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.

An orally active motilin receptor antagonist, MA-2029, inhibits motilin-induced gastrointestinal motility, increase in fundic tone, and diarrhea in conscious dogs without affecting gastric emptying.

PubMed

Ozaki, Ken-ichi; Onoma, Mitsu; Muramatsu, Hiroyasu; Sudo, Hirokazu; Yoshida, Shoshin; Shiokawa, Rie; Yogo, Kenji; Kamei, Kenshi; Cynshi, Osamu; Kuromaru, Osamu; Peeters, Theo L; Takanashi, Hisanori

2009-08-01

The pharmacological properties of MA-2029, a selective and competitive motilin receptor antagonist, were investigated in conscious dogs after oral administration. Gastrointestinal contractile activity was recorded by chronically implanted force transducers. The proximal gastric volume was measured with a barostat under constant pressure. Gastric emptying was examined using the paracetamol absorption test. MA-2029 (0.3-10 mg/kg, p.o.) administered in the interdigestive state inhibited gastrointestinal contractions induced by motilin (3 microg/kg, i.v.) in a dose-dependent manner. MA-2029 (0.3-3 mg/kg, p.o.) also inhibited the occurrence of spontaneous phase III contractions, even though MA-2029 had no effect on basal gastrointestinal motility or basal gastric emptying even at 10 and 30 mg/kg p.o. The inhibitory effect of MA-2029 on motilin-induced gastrointestinal motility corresponded to its plasma concentration. Motilin (0.3 microg/kg/h, i.v. infusion) reduced the proximal gastric volume by about 50% of control during isobaric distension. This effect was also inhibited by MA-2029 (1-10 mg/kg, p.o.) in a dose-dependent manner. In the digestive state, injection of motilin (3 microg/kg, i.v.) induced diarrhea in 9 of 11 dogs. MA-2029 (1-30 mg/kg, p.o.) reduced the incidence of diarrhea induced by motilin in a dose-dependent manner. The results indicate that MA-2029 inhibits hypermotility induced by motilin in conscious dogs without having an effect on the basal gastrointestinal tone or gastric emptying rate. MA-2029 may be useful in treating gastrointestinal disorders in which the pathogenesis involves the elevation of circulating motilin.

Assessment of phosphamidon-induced apoptosis in human peripheral blood mononuclear cells: protective effects of N-acetylcysteine and curcumin.

PubMed

Ahmed, Tanzeel; Tripathi, Ashok K; Ahmed, Rafat S; Banerjee, Basu Dev

2010-01-01

The molecular mechanism for noncholinergic toxicity of phosphamidon, an extensively used organophosphate pesticide, is still not clear. The aim of the present study is to find the possible molecular mechanism of this pesticide to induce apoptosis and the role of different drugs for attenuation of such effects. Human peripheral blood mononuclear cells (PBMC) were incubated with increasing concentrations of phosphamidon (0-20 μM) for 6-24 h. The MTT assay reveals that phosphamidon induces cytotoxicity in a dose-dependent manner. Cellular glutathione (GSH) is depleted in a dose-dependent manner from 55% to 70% at concentrations between 10 and 20 μM. The percentage of cells that bind to Annexin-V, which is a representative of cells either undergoing apoptosis or necrosis during 24 h incubation, increases in a dose-dependent manner. Above 5 μM, significant necrosis of cells was observed. DNA fragmentation assay revealed that at low concentration of phosphamidon (1 μM), no appreciable change in DNA fragmentation was seen; however, distinct fragmentation was observed beyond 2.5 μM. Phosphamidon was found to cause significant depletion of GSH, which correlates well with the percentage of cells undergoing apoptosis. An increasing trend in levels of cytochrome c was observed with increasing concentration of phosphamidon, indicating that the apoptotic effect of phosphamidon is mediated through cytochrome c release. Coadministration of the antioxidants N-acetylcysteine and curcumin attenuated phosphamidon-induced apoptosis. This further supports our hypothesis that oxidative stress, as indicated by GSH depletion, results in the induction of apoptosis by release of cytochrome c. Copyright 2010 Wiley Periodicals, Inc.

Pharmacologic inhibition of lactate production prevents myofibroblast differentiation.

PubMed

Kottmann, Robert Matthew; Trawick, Emma; Judge, Jennifer L; Wahl, Lindsay A; Epa, Amali P; Owens, Kristina M; Thatcher, Thomas H; Phipps, Richard P; Sime, Patricia J

2015-12-01

Myofibroblasts are one of the primary cell types responsible for the accumulation of extracellular matrix in fibrosing diseases, and targeting myofibroblast differentiation is an important therapeutic strategy for the treatment of pulmonary fibrosis. Transforming growth factor-β (TGF-β) has been shown to be an important inducer of myofibroblast differentiation. We previously demonstrated that lactate dehydrogenase and its metabolic product lactic acid are important mediators of myofibroblast differentiation, via acid-induced activation of latent TGF-β. Here we explore whether pharmacologic inhibition of LDH activity can prevent TGF-β-induced myofibroblast differentiation. Primary human lung fibroblasts from healthy patients and those with pulmonary fibrosis were treated with TGF-β and or gossypol, an LDH inhibitor. Protein and RNA were analyzed for markers of myofibroblast differentiation and extracellular matrix generation. Gossypol inhibited TGF-β-induced expression of the myofibroblast marker α-smooth muscle actin (α-SMA) in a dose-dependent manner in both healthy and fibrotic human lung fibroblasts. Gossypol also inhibited expression of collagen 1, collagen 3, and fibronectin. Gossypol inhibited LDH activity, the generation of extracellular lactic acid, and the rate of extracellular acidification in a dose-dependent manner. Furthermore, gossypol inhibited TGF-β bioactivity in a dose-dependent manner. Concurrent treatment with an LDH siRNA increased the ability of gossypol to inhibit TGF-β-induced myofibroblast differentiation. Gossypol inhibits TGF-β-induced myofibroblast differentiation through inhibition of LDH, inhibition of extracellular accumulation of lactic acid, and inhibition of TGF-β bioactivity. These data support the hypothesis that pharmacologic inhibition of LDH may play an important role in the treatment of pulmonary fibrosis. Copyright © 2015 the American Physiological Society.

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

PubMed Central

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

2017-01-01

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

Plasma growth hormone (GH), insulin and amino acid responses to arginine with or without aspartic acid in pigs. Effect of the dose.

PubMed

Cochard, A; Guilhermet, R; Bonneau, M

1998-01-01

The aim of the present study was to examine, for the first time in pigs, the dose-dependent effect of arginine (ARG) on growth hormone (GH) and insulin release and the effect of the combined ARG and aspartic acid (ASP) treatment on GH and insulin release. ARG (0.5 or 1 g/kg body weight) with or without an equimolar supplement of ASP (0.38 or 0.76 g/kg, respectively) was administered in piglets via the duodenum. ARG increased plasma arginine, ornithine, urea, proline and branched chain amino acid concentrations. ASP increased specifically plasma aspartic acid, glutamic acid, alanine and citrulline concentrations. Plasma insulin increased with no apparent difference between treatments. Maximum GH level and the area under the GH curve (AUC) were increased in a dose-dependent manner in response to ARG treatment. GH response to the combined ARG and ASP treatment (ARGASP) was delayed compared to ARG alone and was not dose-dependent. AUC for GH after ARGASP treatments were intermediate between those observed after the two ARG doses. Our data suggest that high ASP doses transiently inhibit and delay ARG-induced GH release in pigs and that an equimolar supplement of ASP stimulates or inhibits ARG-induced GH release depending on the dose used.

Cell-specific STORM super-resolution imaging reveals nanoscale organization of cannabinoid signaling.

PubMed

Dudok, Barna; Barna, László; Ledri, Marco; Szabó, Szilárd I; Szabadits, Eszter; Pintér, Balázs; Woodhams, Stephen G; Henstridge, Christopher M; Balla, Gyula Y; Nyilas, Rita; Varga, Csaba; Lee, Sang-Hun; Matolcsi, Máté; Cervenak, Judit; Kacskovics, Imre; Watanabe, Masahiko; Sagheddu, Claudia; Melis, Miriam; Pistis, Marco; Soltesz, Ivan; Katona, István

2015-01-01

A major challenge in neuroscience is to determine the nanoscale position and quantity of signaling molecules in a cell type- and subcellular compartment-specific manner. We developed a new approach to this problem by combining cell-specific physiological and anatomical characterization with super-resolution imaging and studied the molecular and structural parameters shaping the physiological properties of synaptic endocannabinoid signaling in the mouse hippocampus. We found that axon terminals of perisomatically projecting GABAergic interneurons possessed increased CB1 receptor number, active-zone complexity and receptor/effector ratio compared with dendritically projecting interneurons, consistent with higher efficiency of cannabinoid signaling at somatic versus dendritic synapses. Furthermore, chronic Δ(9)-tetrahydrocannabinol administration, which reduces cannabinoid efficacy on GABA release, evoked marked CB1 downregulation in a dose-dependent manner. Full receptor recovery required several weeks after the cessation of Δ(9)-tetrahydrocannabinol treatment. These findings indicate that cell type-specific nanoscale analysis of endogenous protein distribution is possible in brain circuits and identify previously unknown molecular properties controlling endocannabinoid signaling and cannabis-induced cognitive dysfunction.

Concentration rather than dose defines the local brain toxicity of agents that are effectively distributed by convection-enhanced delivery.

PubMed

Zhang, Rong; Saito, Ryuta; Mano, Yui; Kanamori, Masayuki; Sonoda, Yukihiko; Kumabe, Toshihiro; Tominaga, Teiji

2014-01-30

Convection-enhanced delivery (CED) has been developed as a potentially effective drug-delivery strategy into the central nervous system. In contrast to systemic intravenous administration, local delivery achieves high concentration and prolonged retention in the local tissue, with increased chance of local toxicity, especially with toxic agents such as chemotherapeutic agents. Therefore, the factors that affect local toxicity should be extensively studied. With the assumption that concentration-oriented evaluation of toxicity is important for local CED, we evaluated the appearance of local toxicity among different agents after delivery with CED and studied if it is dose dependent or concentration dependent. Local toxicity profile of chemotherapeutic agents delivered via CED indicates BCNU was dose-dependent, whereas that of ACNU was concentration-dependent. On the other hand, local toxicity for doxorubicin, which is not distributed effectively by CED, was dose-dependent. Local toxicity for PLD, which is extensively distributed by CED, was concentration-dependent. Traditional evaluation of drug induced toxicity was dose-oriented. This is true for systemic intravascular delivery. However, with local CED, toxicity of several drugs exacerbated in concentration-dependent manner. From our study, local toxicity of drugs that are likely to distribute effectively tended to be concentration-dependent. Concentration rather than dose may be more important for the toxicity of agents that are effectively distributed by CED. Concentration-oriented evaluation of toxicity is more important for CED. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation of antipyretic potential of Vernonia cinerea extract in rats.

PubMed

Gupta, Malaya; Mazumder, U K; Manikandan, L; Bhattacharya, S; Haldar, P K; Roy, S

2003-08-01

The methanol extract of the whole plant of Vernonia cinerea (MEVC) was evaluated for its antipyretic potential on normal body temperature and yeast-induced pyrexia in rats. MEVC significantly reduced the normal body temperature at doses of 250 and 500 mg/kg body weight p.o. MEVC also lowered the elevated body temperature in the case of yeast-induced pyrexia in a dose dependent manner. The antipyretic effect of the extract at a dose of 500 mg/kg was identical to that of the standard drug paracetamol. Copyright 2003 John Wiley & Sons, Ltd.

A non-human primate model of radiation-induced cachexia.

PubMed

Cui, Wanchang; Bennett, Alexander W; Zhang, Pei; Barrow, Kory R; Kearney, Sean R; Hankey, Kim G; Taylor-Howell, Cheryl; Gibbs, Allison M; Smith, Cassandra P; MacVittie, Thomas J

2016-03-31

Cachexia, or muscle wasting, is a serious health threat to victims of radiological accidents or patients receiving radiotherapy. Here, we propose a non-human primate (NHP) radiation-induced cachexia model based on clinical and molecular pathology findings. NHP exposed to potentially lethal partial-body irradiation developed symptoms of cachexia such as body weight loss in a time- and dose-dependent manner. Severe body weight loss as high as 20-25% was observed which was refractory to nutritional intervention. Radiographic imaging indicated that cachectic NHP lost as much as 50% of skeletal muscle. Histological analysis of muscle tissues showed abnormalities such as presence of central nuclei, inflammation, fatty replacement of skeletal muscle, and muscle fiber degeneration. Biochemical parameters such as hemoglobin and albumin levels decreased after radiation exposure. Levels of FBXO32 (Atrogin-1), ActRIIB and myostatin were significantly changed in the irradiated cachectic NHP compared to the non-irradiated NHP. Our data suggest NHP that have been exposed to high dose radiation manifest cachexia-like symptoms in a time- and dose-dependent manner. This model provides a unique opportunity to study the mechanism of radiation-induced cachexia and will aid in efficacy studies of mitigators of this disease.

The inhibitory effect of vitamin K on RANKL-induced osteoclast differentiation and bone resorption.

PubMed

Wu, Wei-Jie; Kim, Min Seuk; Ahn, Byung-Yong

2015-10-01

To further understand the correlation between vitamin K and bone metabolism, the effects of vitamins K1, menaquinone-4 (MK-4), and menaquinone-7 (MK-7) on RANKL-induced osteoclast differentiation and bone resorption were comparatively investigated. Vitamin K2 groups (MK-4 and MK-7) were found to significantly inhibit RANKL-medicated osteoclast cell formation of bone marrow macrophages (BMMs) in a dose-dependent manner, without any evidence of cytotoxicity. The mRNA expression of specific osteoclast differentiation markers, such as c-Fos, NFATc1, OSCAR, and TRAP, as well as NFATc1 protein expression and TRAP activity in RANKL-treated BMMs were inhibited by vitamin K2, although MK-4 exhibited a significantly greater efficiency compared to MK-7. In contrast, the same dose of vitamin K1 had no inhibitory effect on RANKL-induced osteoclast cell formation, but increased the expression of major osteoclastogenic genes. Interestingly, vitamins K1, MK-4 and MK-7 all strongly inhibited osteoclastic bone resorption (p < 0.01) in a dose dependent manner. These results suggest that vitamins K1, MK-4 and MK-7 have anti-osteoporotic properties, while their regulation effects on osteoclastogenesis are somewhat different.

Protective Effect of 4-(3,4-Dihydroxyphenyl)-3-Buten-2-One from Phellinus linteus on Naproxen-Induced Gastric Antral Ulcers in Rats.

PubMed

Kim, Jeong-Hwan; Kwon, Hyun Ju; Kim, Byung Woo

2016-05-28

The present study investigated the protective effect of naturally purified 4-(3,4- dihydroxyphenyl)-3-buten-2-one (DHP) from Phellinus linteus against naproxen-induced gastric antral ulcers in rats. To verify the protective effect of DHP on naproxen-induced gastric antral ulcers, various doses (1, 5, and 10 μg/kg) of DHP were pretreated for 3 days, and then gastric damage was caused by 80 mg/kg naproxen applied for 3 days. DHP prevented naproxen-induced gastric antral ulcers in a dose-dependent manner. In particular, 10 μg/kg DHP showed the best protective effect against naproxen-induced gastric antral ulcers. Moreover, DHP significantly attenuated the naproxen-induced lipid peroxide level in gastric mucosa and increased the activities of radical scavenging enzymes, such as superoxide dismutase, catalase, and glutathione peroxidase, in a dose-dependent manner. A histological examination clearly demonstrated that the gastric antral ulcer induced by naproxen nearly disappeared after the pretreatment of DHP. These results suggest that DHP can inhibit naproxen-induced gastric antral ulcers through prevention of lipid peroxidation and activation of radical scavenging enzymes.

A mid-morning snack of almonds generates satiety and appropriate adjustment of subsequent food intake in healthy women.

PubMed

Hull, Sarah; Re, Roberta; Chambers, Lucy; Echaniz, Ana; Wickham, Martin S J

2015-08-01

To assess the effect of consuming a mid-morning almond snack (28 and 42 g) tested against a negative control of no almonds on acute satiety responses. On three test days, 32 healthy females consumed a standard breakfast followed by 0, 28 or 42 g of almonds as a mid-morning snack and then ad libitum meals at lunch and dinner. The effect of the almond snacks on satiety was assessed by measuring energy intake (kcal) at the two ad libitum meals and subjective appetite ratings (visual analogue scales) throughout the test days. Intake at lunch and dinner significantly decreased in a dose-dependent manner in response to the almond snacks. Overall, a similar amount of energy was consumed on all three test days indicating that participants compensated for the 173 and 259 kcals consumed as almonds on the 28 and 42 g test days, respectively. Subjective appetite ratings in the interval between the mid-morning snack and lunch were consistent with dose-dependent enhanced satiety following the almond snacks. However, in the interval between lunch and dinner, appetite ratings were not dependent on the mid-morning snack. Almonds might be a healthy snack option since their acute satiating effects are likely to result in no net increase in energy consumed over a day.

Effect of soy saponin on the growth of human colon cancer cells

PubMed Central

Tsai, Cheng-Yu; Chen, Yue-Hwa; Chien, Yi-Wen; Huang, Wen-Hsuan; Lin, Shyh-Hsiang

2010-01-01

AIM: To investigate the effect of extracted soybean saponins on the growth of human colon cancer cells. METHODS: WiDr human colon cancer cells were treated with 150, 300, 600 or 1200 ppm of soy saponin to determine the effect on cell growth, cell morphology, alkaline phosphatase (AP) and protein kinase C (PKC) activities, and P53 protein, c-Fos and c-Jun gene expression. RESULTS: Soy saponin decreased the number of viable cells in a dose-dependent manner and suppressed 12-O-tetradecanol-phorbol-13-acetate-stimulated PKC activity (P < 0.05). Cells treated with saponins developed cytoplasmic vesicles and the cell membrane became rougher and more irregular in a dose-dependent manner, and eventually disassembled. At 600 and 1200 ppm, the activity of AP was increased (P < 0.05). However, the apoptosis markers such as c-Jun and c-Fos were not significantly affected by saponin. CONCLUSION: Soy saponin may be effective in preventing colon cancer by affecting cell morphology, cell proliferation enzymes, and cell growth. PMID:20632438

[Saponin 6 of Anemone Taipaiensis inhibits proliferation and induces apoptosis of U87 MG cells].

PubMed

Ji, Chenchen; Cheng, Guang; Tang, Haifeng; Zhang, Yun; Hu, Yiyang; Zheng, Minhua; Fei, Zhou

2015-04-01

To investigate the effect of saponin 6 of Anemone Taipaiensis on the proliferation of human U87 MG glioma cells and the possible mechanism. U87 MG cells were treated with different concentrations of saponin 6 (0.0, 1.6, 3.2, 6.4, 12.8 μg/mL) for 24 hours or 48 hours. Cell viability was measured by MTT assay; the apoptosis rate was detected by flow cytometry combined with annexin V-FITC /PI staining; Western blotting was applied to determine the protein level of activated caspase-3. Compared with control groups, saponin 6 significantly inhibited U87 MG cell proliferation in a time- and dose-depended manner. Apoptosis rate of U87 MG cells and the expression of activated caspase-3 were raised with the increasing concentration of saponin 6. Saponin 6 of Anemone Taipaiensis could depress cell proliferation in a dose-depended manner, increase the expression of activated caspase-3 and promote apoptosis in U87 MG cells.

JS-K promotes apoptosis by inducing ROS production in human prostate cancer cells.

PubMed

Qiu, Mingning; Chen, Lieqian; Tan, Guobin; Ke, Longzhi; Zhang, Sai; Chen, Hege; Liu, Jianjun

2017-03-01

Reactive oxygen species (ROS) are chemical species that alter redox status, and are responsible for inducing carcinogenesis. The purpose of the present study was to assess the effects of the glutathione S transferase-activated nitric oxide donor prodrug, JS-K, on ROS accumulation and on proliferation and apoptosis in human prostate cancer cells. Cell proliferation and apoptosis, ROS accumulation and the activation of the mitochondrial signaling pathway were measured. The results demonstrated that JS-K may inhibit prostate cancer cell growth in a dose- and time-dependent manner, and induce ROS accumulation and apoptosis in a dose-dependent manner. With increasing concentrations of JS-K, expression of pro-apoptotic proteins increased, but Bcl-2 expression decreased. Additionally, the antioxidant N-acetylcysteine reversed JS-K-induced cell apoptosis; conversely, the pro-oxidant glutathione disulfide exacerbated JS-K-induced apoptosis. In conclusion, the data suggest that JS-K induces prostate cancer cell apoptosis by increasing ROS levels.

JS-K promotes apoptosis by inducing ROS production in human prostate cancer cells

PubMed Central

Qiu, Mingning; Chen, Lieqian; Tan, Guobin; Ke, Longzhi; Zhang, Sai; Chen, Hege; Liu, Jianjun

2017-01-01

Reactive oxygen species (ROS) are chemical species that alter redox status, and are responsible for inducing carcinogenesis. The purpose of the present study was to assess the effects of the glutathione S transferase-activated nitric oxide donor prodrug, JS-K, on ROS accumulation and on proliferation and apoptosis in human prostate cancer cells. Cell proliferation and apoptosis, ROS accumulation and the activation of the mitochondrial signaling pathway were measured. The results demonstrated that JS-K may inhibit prostate cancer cell growth in a dose- and time-dependent manner, and induce ROS accumulation and apoptosis in a dose-dependent manner. With increasing concentrations of JS-K, expression of pro-apoptotic proteins increased, but Bcl-2 expression decreased. Additionally, the antioxidant N-acetylcysteine reversed JS-K-induced cell apoptosis; conversely, the pro-oxidant glutathione disulfide exacerbated JS-K-induced apoptosis. In conclusion, the data suggest that JS-K induces prostate cancer cell apoptosis by increasing ROS levels. PMID:28454225

3D printed alendronate-releasing poly(caprolactone) porous scaffolds enhance osteogenic differentiation and bone formation in rat tibial defects.

PubMed

Kim, Sung Eun; Yun, Young-Pil; Shim, Kyu-Sik; Kim, Hak-Jun; Park, Kyeongsoon; Song, Hae-Ryong

2016-09-29

The aim of this study was to evaluate the in vitro osteogenic effects and in vivo new bone formation of three-dimensional (3D) printed alendronate (Aln)-releasing poly(caprolactone) (PCL) (Aln/PCL) scaffolds in rat tibial defect models. 3D printed Aln/PCL scaffolds were fabricated via layer-by-layer deposition. The fabricated Aln/PCL scaffolds had high porosity and an interconnected pore structure and showed sustained Aln release. In vitro studies showed that MG-63 cells seeded on the Aln/PCL scaffolds displayed increased alkaline phosphatase (ALP) activity and calcium content in a dose-dependent manner when compared with cell cultures in PCL scaffolds. In addition, in vivo animal studies and histologic evaluation showed that Aln/PCL scaffolds implanted in a rat tibial defect model markedly increased new bone formation and mineralized bone tissues in a dose-dependent manner compared to PCL-only scaffolds. Our results show that 3D printed Aln/PCL scaffolds are promising templates for bone tissue engineering applications.

[Effect of taspine derivatives on human liver cancer SMMC7721].

PubMed

Zhang, Yan-min; Wang, Nan; Dai, Bing-ling; He, Lang-chong

2011-07-01

To analyse the inhibition effect of taspine derivatives on human Liver cancer SMMC7721 cell and its mechanism. The effects of five taspine derivatives on SMMC7721 cell growth were determined by MTT. The flow cytometry was used to determine the cell cycle. The effects of Tas-D1 on the EGF and VEGF in SMMC7721 cell were determined by ELISA. The mRNA level of EGF and VEGF in SMMC7721 cell was determined by RT-PCR. The MTT assay demonstrated that the taspine derivative Tas-D1 significantly inhibited the growth of SMMC7721 cell in a dose-dependent manner. Cell was stopped at S phase by Tas-D1. Tas-D1 inhibited the expression of EGF and VEGF and their mRNA in a dose-dependent manner (P<0.05). The taspine derivative Tas-D1 can inhibit the growth of human Liver cancer SMMC7721 cell and change cell cycle, which may be related to the inhibition of EGF and VEGF expression.

Antioxidant protects blood-testis barrier against synchrotron radiation X-ray-induced disruption

PubMed Central

Zhang, Tingting; Liu, Tengyuan; Shao, Jiaxiang; Sheng, Caibin; Hong, Yunyi; Ying, Weihai; Xia, Weiliang

2015-01-01

Synchrotron radiation (SR) X-ray has wide biomedical applications including high resolution imaging and brain tumor therapy due to its special properties of high coherence, monochromaticity and high intensity. However, its interaction with biological tissues remains poorly understood. In this study, we used the rat testis as a model to investigate how SR X-ray would induce tissue responses, especially the blood-testis barrier (BTB) because BTB dynamics are critical for spermatogenesis. We irradiated the male gonad with increasing doses of SR X-ray and obtained the testicles 1, 10 and 20 d after the exposures. The testicle weight and seminiferous tubule diameter reduced in a dose- and time-dependent manner. Cryosections of testes were stained with tight junction (TJ) component proteins such as occludin, claudin-11, JAM-A and ZO-1. Morphologically, increasing doses of SR X-ray consistently induced developing germ cell sloughing from the seminiferous tubules, accompanied by shrinkage of the tubules. Interestingly, TJ constituent proteins appeared to be induced by the increasing doses of SR X-ray. Up to 20 d after SR X-ray irradiation, there also appeared to be time-dependent changes on the steady-state level of these protein exhibiting differential patterns at 20-day after exposure, with JAM-A/claudin-11 still being up-regulated whereas occludin/ZO-1 being down-regulated. More importantly, the BTB damage induced by 40 Gy of SR X-ray could be significantly attenuated by antioxidant N-Acetyl-L-Cysteine (NAC) at a dose of 125 mg/kg. Taken together, our studies characterized the changes of TJ component proteins after SR X-ray irradiation, illustrating the possible protective effects of antioxidant NAC to BTB integrity. PMID:26413412

Dose-dependent effect of fluoride on clinical and subclinical indices of fluorosis in school going children and its mitigation by supply of safe drinking water for 5 years: an Indian study.

PubMed

Khandare, Arjun L; Validandi, Vakdevi; Gourineni, Shankar Rao; Gopalan, Viswanathan; Nagalla, Balakrishna

2018-02-02

Fluorosis is a public health problem in India; to know its prevalence and severity along with its mitigation measures is very important. The present study has been undertaken with the aim to assess the F dose-dependent clinical and subclinical symptoms of fluorosis and reversal of the disease by providing safe drinking water. For this purpose, a cross-sectional study was undertaken in 1934 schoolgoing children, Nalgonda district. Study villages were categorized into control (category I, F = 0.87 mg/L), affected (category II, F = 2.53 mg/L, and category III, F = 3.77 mg/L), and intervention categories (category IV, F = < 1.0 mg/L). School children were enrolled for dental grading by modified Dean Index criteria. Anthropometric measurements (height and weight) were used to assess nutritional status of the children. The biochemical parameters like serum T3, T4, TSH, PTH, ALP, 25-OH vitamin D, and 1,25-(OH) 2 vitamin D were analyzed. The results showed a positive correlation between the drinking water and urinary fluoride (UF) in different categories. However, there was a significant decrease in the UF levels in the intervention category IV compared to affected group (category III). Fluoride altered the clinical (dental fluorosis and stunting) and subclinical indices (urine and blood) of fluorosis in a dose-dependent manner. In conclusion, the biochemical indices were altered in a dose-dependent manner and intervention with safe drinking water for 5 years in intervention group-mitigated clinical and subclinical symptoms of fluorosis.

Immunomodulatory effect of Moringa peregrina leaves, ex vivo and in vivo study

PubMed Central

Al-Oran, Sawsan Atallah; Hassuneh, Mona Rushdie; Al-Qaralleh, Haitham Naief; Rayyan, Walid Abu; Al-Thunibat, Osama Yosef; Mallah, Eyad; Abu-Rayyan, Ahmed; Salem, Shadi

2017-01-01

This study was conducted to assess the in vivo and ex vivo immunomodulatory effect of the ethanol leaves extract of Moringa peregrina in Balb/c mice. For this study, five groups of 5 Balb/c mice were given a single acute subtoxic oral dose of the ethanolic extract at 1.13, 11.30, 23.40 and 113.4 mg/kg and the immunomodulatory effect was assessed on the 6th day following the ingestion. In the (non-functional) assessment, the effect of the extract on the body weight, relative lymphoid organ weight, splenic cellularity and peripheral blood hematologic parameters were evaluated. While in the immunomodulation assessment (functional), we investigated the effect of the extract on the proliferative capacity of splenic lymphocytes and peripheral T and B lymphocytes using mitogen blastogenesis, mixed allogeneic MLR and IgM-Plaque forming cells assays. The ingestion of M. peregrina extract caused a significant increase in the body weight, weight and number of cells of spleen and lymph nodes of the treated mice. Furthermore, the count of RBCs, WBCs, platelets, hemoglobin concentration and PCV % were increased by the extract treatment in a dose-dependent manner. M. peregrina enhanced the proliferative responses of splenic lymphocytes for both T cell and B-cell mitogens. Likewise, the mixed lymphocyte reaction MLR assay has revealed a T-cell dependent proliferation enhancement in the extract treated mice. Moreover, the oral administration of M. peregrina leaves extracts significantly increased PFCs/106 splenocytes in a dose-dependent manner. In conclusion, subtoxic acute doses of M. peregrina extract demonstrated significant potential as an immunomodulatory agent even at the lowest dose of 1.13 mg/kg. PMID:29204086

Sodium chloride inhibits IFN-γ, but not IL-4, production by invariant NKT cells.

PubMed

Jeong, Dongjin; Kim, Hye Young; Chung, Doo Hyun

2018-01-01

Invariant NKT (iNKT) cells are a distinct subset of T cells that exert Janus-like functions in vivo by producing IFN-γ and IL-4. Sodium chloride modulates the functions of various immune cells, including conventional CD4 + T cells and macrophages. However, it is not known whether sodium chloride affects iNKT cell function, so we addressed this issue. Sodium chloride inhibited IFN-γ, but not IL-4, production by iNKT cells upon TCR or TCR-independent (IL-12 and IL-18) stimulation in a dose-dependent manner. Consistently, sodium chloride reduced the expression level of tbx21, but not gata-3, in iNKT cells stimulated with TCR engagement or IL-12 + IL-18. Sodium chloride increased phosphorylated p38 expression in iNKT cells and inhibitors of p38, NFAT5, SGK1, and TCF-1 restored IFN-γ production by iNKT cells stimulated with sodium chloride and TCR engagement. Furthermore, adoptive transfer of iNKT cells pretreated with sodium chloride restored antibody-induced joint inflammation to a lesser extent than for untreated iNKT cells in Jα18 knockout mice. These findings suggest that sodium chloride inhibits IFN-γ production by iNKT cells in TCR-dependent and TCR-independent manners, which is dependent on p38, NFAT5, SGK1, and TCF-1. These findings highlight the functional role of sodium chloride in iNKT cell-mediated inflammatory diseases. ©2017 Society for Leukocyte Biology.

Dose-dependent metabolic disposition of hydroxytyrosol and formation of mercapturates in rats.

PubMed

Kotronoulas, Aristotelis; Pizarro, Nieves; Serra, Aida; Robledo, Patricia; Joglar, Jesús; Rubió, Laura; Hernaéz, Alvaro; Tormos, Carmen; Motilva, Ma José; Fitó, Montserrat; Covas, Maria-Isabel; Solà, Rosa; Farré, Magí; Saez, Guillermo; de la Torre, Rafael

2013-11-01

Hydroxytyrosol (HT), one of the major polyphenols present in olive oil, is known to possess a high antioxidant capacity. The aim of the present study was to investigate dose dependent (0, 1, 10 and 100 mg/kg) alterations in the metabolism of HT in rats since it has been reported that metabolites may contribute to biological effects. Special attention was paid to the activation of the semiquinone-quinone oxidative cycle and the formation of adducts with potential deleterious effects. Thus, we developed a novel analytical methodology to monitor the in vivo formation of the HT mercapturate, N-acetyl-5-S-cysteinyl-hydroxytyrosol in urine samples. Biomarkers of hepatic and renal toxicity were evaluated within the dose range tested. Following HT administration, dose-dependent effects were observed for the recovery of all the metabolites studied. At the lowest dose of 1 mg/kg, the glucuronidation pathway was the most relevant (25-30%), with lower recoveries for sulfation (14%), while at the highest dose of 100 mg/kg, sulfation was the most prevalent (75%). In addition, we report for the first time the formation of the mercapturate conjugate of HT in a dose-dependent manner. The biochemical data did not reveal significant toxic effects of HT at any of the doses studied. An increase in the GSH/GSSG ratio at the highest dose was observed indicating that the products of HT autoxidation are counteracted by glutathione, resulting in their detoxification. These results indicate that the metabolic disposition of HT is highly dependent on the dose ingested. Copyright © 2013. Published by Elsevier Ltd.

A first-in-human pharmacodynamic and pharmacokinetic study of a fully human anti-glucagon receptor monoclonal antibody in normal healthy volunteers.

PubMed

Kostic, Ana; King, Thomas Alexander; Yang, Feng; Chan, Kuo-Chen; Yancopoulos, George D; Gromada, Jesper; Harp, Joyce B

2018-02-01

Glucagon receptor (GCGR) blockers are being investigated as potential therapeutics for type 1 and type 2 diabetes. Here we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of REGN1193, a fully human glucagon receptor blocking monoclonal antibody from a first-in-human healthy volunteer randomized double-blinded trial. Healthy men and women received single ascending doses of REGN1193 ranging from 0.05 to 0.6 mg/kg (n = 42) or placebo (n = 14) intravenously. Safety, tolerability and PK were assessed over 106 days. The glucose-lowering effect of REGN1193 was assessed after induction of hyperglycaemia by serial glucagon challenges. REGN1193 was generally well tolerated. There were small (<3× the upper limit of normal) and transient dose-dependent increases in hepatic aminotransferases. No increase in LDL-C was observed. Hypoglycaemia, assessed as laboratory blood glucose ≤70 mg/dL, occurred in 6/14 (43%) subjects on placebo and 27/42 (57%) on REGN1193 across all dose groups. All episodes of hypoglycaemia were asymptomatic, >50 mg/dL, and did not require treatment or medical assistance. Concentration-time profiles suggest a 2-compartment disposition and marked nonlinearity, consistent with target-mediated clearance. REGN1193 inhibited the glucagon-stimulated glucose increase in a dose-dependent manner. The 0.6 mg/kg dose inhibited the glucagon-induced glucose area under the curve for 0 to 90 minutes (AUC 0-90 minutes ) by 80% to 90% on days 3 and 15, while blunting the increase in C-peptide. REGN1193 dose-dependently increased total GLP-1, GLP-2 and glucagon, with plasma levels returning to baseline by day 29 in all dose groups. REGN1193, a GCGR-blocking monoclonal antibody, produced a safety, tolerability and PK/PD profile suitable for further clinical development. The occurrence of transient elevations in serum hepatic aminotransferases observed here and reported with several small molecule glucagon receptor antagonists suggests an on-target effect of glucagon receptor blockade. The underlying mechanism is unknown. © 2017 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Achieving Consistent Multiple Daily Low-Dose Bacillus anthracis Spore Inhalation Exposures in the Rabbit Model

DTIC Science & Technology

2012-06-13

plethysmography. Overall, the presented results show that the animal aerosol system was stable and highly reproducible between different studies and over...develop and deliver low-doses of B. anthracis spores via inhalation in a reproducible manner. The pilot feasibility study (see Table 1 for results) enabled...results presented in Figure 3 show that exposures produced by the aerosol system were stable and reproducible from day-to-day. In all testing, the

Reduction of antiproliferative capacities, cell-based antioxidant capacities and phytochemical contents of common beans and soybeans upon thermal processing.

PubMed

Xu, Baojun; Chang, Sam K C

2011-12-01

The effects of boiling and steaming processes on the antiproliferative and cellular antioxidant properties, as well as phytochemicals, of two types of common beans (pinto and black beans) and two types of soybeans (yellow and black) were investigated. All thermal-processing methods caused significant (p<0.05) decreases in total phenolic content (TPC), total saponin content (TSC) and phytic acid content (PAC) values in all bean types (except for TPC values in pressure-steamed yellow soybeans) as compared to those of the raw beans. All types of uncooked raw beans exhibited cellular antioxidant activities (CAA) in dose-dependent manners. Black soybeans exhibited the greatest CAA, followed by black beans, pinto beans and yellow soybeans. The CAA of cooked beans were generally diminished or eliminated by thermal processing. The hydrophilic extracts from raw pinto beans, black beans and black soybeans exhibited antiproliferation capacities against human gastric (AGS) and colorectal (SW480) cancer cells in dose-dependent manners. The raw yellow soybeans exhibited dose-dependent antiproliferation activities against the SW480 cells. Most of the cooked beans lost their antiproliferation capacities as observed in the raw beans. These results indicate that different processing methods may have various effects on phytochemical profiles and bioactivities. Overall, thermal processing caused a significant reduction of the health-promotion effects of beans. Copyright © 2011 Elsevier Ltd. All rights reserved.

Enhancement of Chaperone Activity of Plant-Specific Thioredoxin through γ-Ray Mediated Conformational Change.

PubMed

Lee, Seung Sik; Jung, Hyun Suk; Park, Soo-Kwon; Lee, Eun Mi; Singh, Sudhir; Lee, Yuno; Lee, Kyun Oh; Lee, Sang Yeol; Chung, Byung Yeoup

2015-11-13

AtTDX, a thioredoxin-like plant-specific protein present in Arabidopsis is a thermo-stable and multi-functional enzyme. This enzyme is known to act as a thioredoxin and as a molecular chaperone depending upon its oligomeric status. The present study examines the effects of γ-irradiation on the structural and functional changes of AtTDX. Holdase chaperone activity of AtTDX was increased and reached a maximum at 10 kGy of γ-irradiation and declined subsequently in a dose-dependent manner, together with no effect on foldase chaperone activity. However, thioredoxin activity decreased gradually with increasing irradiation. Electrophoresis and size exclusion chromatography analysis showed that AtTDX had a tendency to form high molecular weight (HMW) complexes after γ-irradiation and γ-ray-induced HMW complexes were tightly associated with a holdase chaperone activity. The hydrophobicity of AtTDX increased with an increase in irradiation dose till 20 kGy and thereafter decreased further. Analysis of the secondary structures of AtTDX using far UV-circular dichroism spectra revealed that the irradiation remarkably increased the exposure of β-sheets and random coils with a dramatic decrease in α-helices and turn elements in a dose-dependent manner. The data of the present study suggest that γ-irradiation may be a useful tool for increasing holdase chaperone activity without adversely affecting foldase chaperone activity of thioredoxin-like proteins.

Formononetin suppresses the proliferation of human non-small cell lung cancer through induction of cell cycle arrest and apoptosis

PubMed Central

Yang, Yi; Zhao, Yi; Ai, Xinghao; Cheng, Baijun; Lu, Shun

2014-01-01

Formononetin is a novel herbal isoflavonoid isolated from Astragalus membranaceus and possesses antitumorigenic properties. In the present study, we investigated the anti-proliferative effects of formononetin on human non-small cell lung cancer (NSCLC), and further elucidated the molecular mechanism underlying the anti-tumor property. MTT assay showed that formononetin treatment significantly inhibited the proliferation of two NSCLC cell lines including A549 and NCI-H23 in a time- and dose-dependent manner. Flow cytometric analysis demonstrated that formononetin induced G1-phase cell cycle arrest and promoted cell apoptosis in NSCLC cells. On the molecular level, we observed that exposure to formononetin altered the expression levels of cell cycle arrest-associated proteins p21, cyclin A and cyclin D1. Meanwhile, the apoptosis-related proteins cleaved caspase-3, bax and bcl-2 were also changed following treatment with formononetin. In addition, the expression level of p53 was dose-dependently upregulated after administration with formononetin. We also found that formononetin treatment increased the phosphorylation of p53 at Ser15 and Ser20 and enhances its transcriptional activity in a dose-dependent manner. Collectively, these results demonstrated that formononetin might be a potential chemopreventive drug for lung cancer therapy through induction of cell cycle arrest and apoptosis in NSCLC cells. PMID:25674209

Determinants of propranolol’s selective effect on loss aversion

PubMed Central

Sokol-Hessner, Peter; Lackovic, Sandra F.; Tobe, Russell H.; Camerer, Colin F.; Leventhal, Bennett L.; Phelps, Elizabeth A.

2015-01-01

Research on emotion and decision-making has suggested that arousal mediates risky decisions (e.g., Bechara et al., 1997), but several distinct and often confounded processes drive such choices. Here, we used econometric modeling to separate and quantify the unique contributions of loss aversion, risk sensitivity and choice consistency to risky decision-making. We administered the beta-blocker propranolol in a double-blind, placebo-controlled within-subjects study, targeting the neurohormonal basis of physiological arousal. Matching our intervention’s pharmacological specificity with a quantitative model delineating decision-making components allowed us to identify the causal relationships between arousal and decision-making that do and do not exist. Propranolol selectively reduced loss aversion in a baseline- and dose-dependent manner (i.e. as a function of initial loss aversion and body-mass index), and did not affect risk sensitivity or choice consistency. These findings provide evidence for a specific, modulatory, and causal relationship between precise components of both emotion and risky decision-making. PMID:26063441

Actin cytoskeleton as a putative target of the neem limonoid Azadirachtin A.

PubMed

Anuradha, Aritakula; Annadurai, Ramaswamy S; Shashidhara, L S

2007-06-01

Limonoids isolated from the Indian neem tree (Azadirachta indica) have been gaining global acceptance in agricultural applications and in contemporary medicine for their myriad but discrete properties. However, their mode of action is still not very well understood. We have studied the mode of action of Azadirachtin A, the major limonoid of neem seed extracts, using Drosophila melanogaster as the model system. Azadirachtin A induces moderate-to-severe phenotypes in different tissues in a dose-dependent manner. At the cellular level, Azadirachtin A induces depolymerization of Actin leading to arrest of cells and subsequently apoptosis in a caspase-independent manner. Azadirachtin A-induced phenotypes were rescued by the over-expression of Cyclin E in a tissue-dependent manner. Cyclin E, which caused global rescue of Azadirachtin A-induced phenotypes, also effected rearrangement of the actin filaments. These results suggest that probably actin is a target of Azadirachtin A activity.

The Effect of Lactobacillus casei 32G on the Mouse Cecum Microbiota and Innate Immune Response Is Dose and Time Dependent

PubMed Central

Aktas, Busra; De Wolfe, Travis J.; Tandee, Kanokwan; Safdar, Nasia; Darien, Benjamin J.; Steele, James L.

2015-01-01

Lactobacilli have been associated with a variety of immunomodulatory effects and some of these effects have been related to changes in gastrointestinal microbiota. However, the relationship between probiotic dose, time since probiotic consumption, changes in the microbiota, and immune system requires further investigation. The objective of this study was to determine if the effect of Lactobacillus casei 32G on the murine gastrointestinal microbiota and immune function are dose and time dependent. Mice were fed L. casei 32G at doses of 106, 107, or 108 CFU/day/mouse for seven days and were sacrificed 0.5h, 3.5h, 12h, or 24h after the last administration. The ileum tissue and the cecal content were collected for immune profiling by qPCR and microbiota analysis, respectively. The time required for L. casei 32G to reach the cecum was monitored by qPCR and the 32G bolus reaches the cecum 3.5h after the last administration. L. casei 32G altered the cecal microbiota with the predominance of Lachnospiraceae IS, and Oscillospira decreasing significantly (p < 0.05) in the mice receiving 108 CFU/mouse 32G relative to the control mice, while a significant (p < 0.05) increase was observed in the prevalence of lactobacilli. The lactobacilli that increased were determined to be a commensal lactobacilli. Interestingly, no significant difference in the overall microbiota composition, regardless of 32G doses, was observed at the 12h time point. A likely explanation for this observation is the level of feed derived-nutrients resulting from the 12h light/dark cycle. 32G results in consistent increases in Clec2h expression and reductions in TLR-2, alpha-defensins, and lysozyme. Changes in expression of these components of the innate immune system are one possible explanation for the observed changes in the cecal microbiota. Additionally, 32G administration was observed to alter the expression of cytokines (IL-10rb and TNF-α) in a manner consistent with an anti-inflammatory response. PMID:26714177

Hepatoprotective potential of ethanolic extract of Ziziphus oenoplia (L.) Mill roots against antitubercular drugs induced hepatotoxicity in experimental models.

PubMed

Rao, Ch V; Rawat, A K S; Singh, Anil P; Singh, Arpita; Verma, Neeraj

2012-04-01

To evaluate the hepatoprotective potential of ethanolic (50%) extract of Ziziphus oenoplia (L.) Mill (Z. oenoplia) root against isoniazid (INH) and rifampicin (RIF) induced liver damage in animal models. Five groups of six rats each were selected for the study. Ethanolic extract at a dose of 150 and 300 mg/kg as well as silymarin (100 mg/kg) were administered orally once daily for 21 d in INH + RIF treated groups. The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), and bilirubin were estimated along with activities of superoxide dismutase, catalase, glutathione S-transferase, glutathione peroxidase, and hepatic melondialdehyde formation. Histopathological analysis was carried out to assess injury to the liver. The considerably elevated serum enzymatic activities of glutamic oxaloacetic transaminase, glutamate pyruvate transaminase, alkaline phosphatase and bilirubin due to INH + RIF treatment were restored towards normal in a dose dependent manner after the treatment with ethanolic extract of Z. oenoplia roots. Meanwhile, the decreased activities of superoxide dismutase, catalase, glutathione S-transferase and glutathione peroxidase were also restored towards normal dose dependently. In addition, ethanolic extract also significantly prevented the elevation of hepatic melondialdehyde formation in the liver of INH + RIF intoxicated rats in a dose dependent manner. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethanolic extract of Z. oenoplia has a potent hepatoprotective action against INH + RIF induced hepatic damage in rats. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Chromosomal aberrations and delays in cell progression induced by x-rays in Tradescantia clone 02 meristems

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

Geard, C.R.

1983-01-01

In root meristems of Tradescantia clone 02 (developed by Sparrow and his colleagues for mutation studies), X-rays interfere with the progression of cells through the cell cycle and induce chromosomal aberrations in a dose-dependent manner consistent with linear-quadratic kinetics. Sequential mitotic cell accumulations after irradiation indicate that sensitivity to aberration induction is probably greatest in cells from late S to early G2, with chromatid interchanges the most frequent aberration type and all aberrations consistent with initiation from the interaction between two lesions. The ratio of the coefficients in the linear (..cap alpha..) and the quadratic (..beta..) terms (..cap alpha../..beta..) ismore » equal to the dose average of specific energy produced by individual particles in the site where interaction takes place. The ratio ..cap alpha../..beta.. for chromosomal aberrations is similar to that previously found for X-ray-induced mutation in Tradescantia stamen hairs, supporting the proposal that radiation-induced mutational events are due to chromosomal aberrations with interaction distances of about 1..mu..m. Abrahamson and co-workers have noted that both ..cap alpha../..beta.. ratios appear to be related to nuclear target size and are similar for chromosomal and mutational endpoints in the same organism. These findings support this concept; however, it is apparent that any situation which diminishes yield at high doses (e.g., mitotic delay) will probably affect the ..beta.. component. 23 references, 5 figures, 2 tables.« less

Chromosomal aberrations and delays in cell progression induced by x-rays in Tradescantia clone 02 meristems

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

Geard, C.R.

1983-01-01

In root meristems of Tradescantia clone 02 (developed by Sparrow and his colleagues for mutation studies), X-rays interfere with the progression of cells through the cell cycle and induce chromosomal aberrations in a dose-dependent manner consistent with linear-quadratic kinetics. Sequential mitotic cell accumulations after irradiation indicate that sensitivity to aberrration induction is probably greatest in cells from late S to early G2, with chromatid interchanges the most frequent aberration type and all aberrations consistent with intiation from the interaction between two lesions. The ratio of the coefficients in the linear (..cap alpha..) and the quadratic (..beta..) terms (..cap alpha../..beta..) ismore » equal to the dose average of specific energy produced by individual particles in the site where interaction takes place. The ratio ..cap alpha../..beta.. for chromosomal aberrations is similar to that previously found for X-ray-induced mutation in Tradescantia stamen hairs, supporting the proposal that radiation-induced mutational events are due to chromosomal aberrations with interaction distances of about 1 ..mu..m. Abrahmson and co-workers have noted that both ..cap alpha../..beta.. ratios appear to be related to nuclear target size and are similar for chromosomal and mutational endpoints in the same organism. These findings support this concept; however, it is apparent that any situation which diminishes yield at high doses (e.g., mitotic delay) will primarily affect the ..beta.. component, resulting in low assessments of interaction site diameters.« less

Bioactive compounds from crocodile (Crocodylus siamensis) white blood cells induced apoptotic cell death in hela cells.

PubMed

Patathananone, Supawadee; Thammasirirak, Sompong; Daduang, Jureerut; Chung, Jing Gung; Temsiripong, Yosapong; Daduang, Sakda

2016-08-01

Crocodile (Crocodylus siamensis) white blood cell extracts (WBCex) were examined for anticancer activity in HeLa cell lines using the MTT assay. The percentage viability of HeLa cells significantly deceased after treatment with WBCex in a dose- and time-dependent manner. The IC50 dose was suggested to be approximately 225 μg/mL protein. Apoptotic cell death occurred in a time-dependent manner based on investigation by flow cytometry using annexin V-FITC and PI staining. DAPI nucleic acid staining indicated increased chromatin condensation. Caspase-3, -8 and -9 activities also increased, suggesting the induction of the caspase-dependent apoptotic pathway. Furthermore, the mitochondrial membrane potential (ΔΨm ) of HeLa cells was lost as a result of increasing levels of Bax and reduced levels of Bcl-2, Bcl-XL, Bcl-Xs, and XIAP. The decreased ΔΨm led to the release of cytochrome c and the activation of caspase-9 and -3. Apoptosis-inducing factor translocated into the nuclei, and endonuclease G (Endo G) was released from the mitochondria. These results suggest that anticancer agents in WBCex can induce apoptosis in HeLa cells via both caspase-dependent and -independent pathways. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 986-997, 2016. © 2015 Wiley Periodicals, Inc.

Inhibitory effects of epigallocatechin-3-gallate on cell proliferation and the expression of HIF-1α and P-gp in the human pancreatic carcinoma cell line PANC-1.

PubMed

Zhu, Zhenni; Wang, Yu; Liu, Zhiqing; Wang, Fan; Zhao, Qiu

2012-05-01

The aim of this study was to verify the inhibitory effects of epigallocatechin-3-gallate (EGCG) on cell proliferation and the expression of hypoxia-inducible factor 1 (HIF-1α) and multidrug resistance protein 1 (MDR1/P-gp) in the human pancreatic carcinoma cell line PANC-1, thereby, reversing drug resistance of pancreatic carcinoma and improving its sensitivity to cancer chemotherapy. The human pancreatic carcinoma cell line PANC-1 was incubated under hypoxic conditions with different concentrations of epigallocatechin-3-gallate (EGCG) for indicated hours. The effects of EGCG on the mRNA or protein expression of HIF-1α and MDR1 were determined by RT-PCR or western blotting. Cellular proliferation and viability assays were measured using Cell Counting Kit-8. Western blotting revealed that EGCG inhibits the expression of the HIF-1α protein in a dose-dependent manner, while RT-PCR showed that it does not have any effects on HIF-1α mRNA. In addition, EGCG attenuated the mRNA and protein levels of P-gp in a dose-dependent manner, reaching a peak at the highest concentration. Furthermore, EGCG inhibited the proliferation of PANC-1 cells in a concentration- and time-dependent manner. The attenuation of HIF-1α and the consequently reduced P-gp could contribute to the inhibitory effects of EGCG on the proliferation of PANC-1 cells.

From topical antidote against skin irritants to a novel counter-irritating and anti-inflammatory peptide

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

Brodsky, Berta; Erlanger-Rosengarten, Avigail; Proscura, Elena

2008-06-15

The primary purpose of the present study was to investigate the mechanism of the counter-irritating activity of topical iodine against skin lesions induced by chemical and thermal stimuli. The hypothesis that iodine exerts its activity by inducing an endogenous anti-inflammatory factor was confirmed by exposing guinea pig skin to heat stimulus followed by topical iodine treatment and skin extraction. Injection of the extract into naive guinea pigs reduced heat-induced irritation by 69%. The protective factor, identified as a new nonapeptide (histone H2A 36-44, H-Lys-Gly-Asn-Tyr-Ala-Glu-Arg-Ileu-Ala-OH), caused reduction of 40% in irritation score in heat-exposed guinea pigs. The murine analog (H-Lys-Gly-His-Tyr-Ala-Glu-Arg-Val-Gly-OH, termedmore » IIIM1) reduced sulfur mustard (SM)-induced ear swelling at a dose-dependent bell-shape manner reaching peak activity of 1 mg/kg. Cultured keratinocytes transfected with the peptide were more resistant towards SM than the control cells. The peptide suppressed oxidative burst in activated neutrophils in a concentration-dependent manner. In addition, the peptide reduced glucose oxidase-induced skin edema in mice at a dose-dependent bell-shape manner. Apart from thermal and chemical-induced skin irritation this novel peptide might be of potential use in chronic dermal disorders such as psoriasis and pemphigus as well as non-dermal inflammatory diseases like multiple sclerosis, arthritis and colitis.« less

Effects of methylmercury and alcohol exposure in Drosophila melanogaster: Potential risks in neurodevelopmental disorders.

PubMed

Chauhan, Ved; Chauhan, Abha

2016-06-01

Extensive evidence suggests the role of oxidative stress in autism and other neurodevelopmental disorders. In this study, we investigated whether methylmercury (MeHg) and/or alcohol exposure has deleterious effects in Drosophila melanogaster (fruit flies). A diet containing different concentrations of MeHg in Drosophila induced free radical generation and increased lipid peroxidation (markers of oxidative stress) in a dose-dependent manner. This effect of MeHg on oxidative stress was enhanced by further exposure to alcohol. It was observed that alcohol alone could also induce free radical generation in flies. After alcohol exposure, MeHg did not affect the immobilization of flies, but it increased the recovery time in a concentration-dependent manner. MeHg significantly inhibited the activity of alcohol dehydrogenase (ADH) in a dose-dependent manner. Linear regression analysis showed a significant negative correlation between ADH activity and recovery time upon alcohol exposure in the flies fed a diet with MeHg. This relationship between ADH activity and recovery time after alcohol exposure was confirmed by adding 4-methyl pyrazole (an inhibitor of ADH) to the diet for the flies. These results suggest that consumption of alcohol by pregnant mothers who are exposed to MeHg may lead to increased oxidative stress and to increased length of time for alcohol clearance, which may have a direct impact on the development of the fetus, thereby increasing the risk of neurodevelopmental disorders. Published by Elsevier Ltd.

GESTATIONAL PFOA EXPOSURE OF MICE IS ASSOCIATED WITH ALTERED MAMMARY GLAND DEVELOPMENT IN DAMS AND FEMALE OFFSPRING

EPA Science Inventory

Perfluorooctanoic acid (PFOA), with diverse and widespread commercial and industrial applications, has been detected in human and wildlife sera. Previous mouse studies linked prenatal PFOA exposure to decreased neonatal body weights (BWs) and survival in a dose-dependent manner. ...

Melanogenesis-inducing effect of cirsimaritin through increases in microphthalmia-associated transcription factor and tyrosinase expression.

PubMed

Kim, Hyo Jung; Kim, Il Soon; Dong, Yin; Lee, Ik-Soo; Kim, Jin Sook; Kim, Jong-Sang; Woo, Je-Tae; Cha, Byung-Yoon

2015-04-20

The melanin-inducing properties of cirsimaritin were investigated in murine B16F10 cells. Cirsimaritin is an active flavone with methoxy groups, which is isolated from the branches of Lithocarpus dealbatus. Tyrosinase activity and melanin content in murine B16F10 melanoma cells were increased by cirsimaritin in a dose-dependent manner. Western blot analysis revealed that tyrosinase, tyrosinase-related protein (TRP) 1, TRP2 protein levels were enhanced after treatment with cirsimaritin for 48 h. Cirsimaritin also upregulated the expression of microphthalmia-associated transcription factor (MITF) after 24 h of treatment. Furthermore, cirsimaritin induced phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) in a dose-dependent manner after treatment for 15 min. The cirsimaritin-mediated increase of tyrosinase activity was significantly attenuated by H89, a cAMP-dependent protein kinase A inhibitor. These findings indicate that cirsimaritin stimulates melanogenesis in B16F10 cells by activation of CREB as well as upregulation of MITF and tyrosinase expression, which was activated by cAMP signaling. Finally, the melanogenic effect of cirsimaritin was confirmed in human epidermal melanocytes. These results support the putative application of cirsimaritin in ultraviolet photoprotection and hair coloration treatments.

Arsenic disulfide induced apoptosis and concurrently promoted erythroid differentiation in cytokine-dependent myelodysplastic syndrome-progressed leukemia cell line F-36p with complex karyotype including monosomy 7.

PubMed

Hu, Xiao-mei; Tanaka, Sachiko; Onda, Kenji; Yuan, Bo; Toyoda, Hiroo; Ma, Rou; Liu, Feng; Hirano, Toshihiko

2014-05-01

Acute myeloid leukemia progressed from myelodysplastic syndrome (MDS/AML) is generally incurable with poor prognosis for complex karyotype including monosomy 7 (-7). Qinghuang Powder (, QHP), which includes Qing Dai (Indigo naturalis) and Xiong Huang (realgar) in the formula, is effective in treating MDS or MDS/AML even with the unfavorable karyotype, and its therapeutic efficacy could be enhanced by increasing the Xiong huang content in the formula, while Xiong huang contains > 90% arsenic disulfide (As2S2). F-36p cell line was established from a MDS/AML patient with complex karyotype including -7, and was in cytokine-dependent. The present study was to investigate the effects of As2S2 on F-36p cells. Cell proliferation was measured by an 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell apoptosis was identified by Annexin V-staining. Cell viability was determined by a propidium iodide (PI) exclusion. Erythroid differentiation was evaluated by the expression of cell surface antigen CD235a (GpA). After treatment with As2S2 at concentrations of 0.5 to 16 μmol/L for 72 h, As2S2 inhibited the proliferation of F-36p cells. The 50% inhibitory concentrations (IC50) of As2S2 against the proliferation of F-36p cells was 6 μmol/L. The apoptotic cells significantly increased in a dose-dependent mannar (P<0.05). The cell viabilities were significantly inhibited by As2S2 dose-dependent in a dose-dependent manner (P<0.05). Significant increases of CD235a-positive cells were concurrently observed (P<0.05) also in a dose-dependent manner. As2S2 could inhibit proliferation and viability, induce apoptosis, and concurrently promote erythroid differentiation dose-dependently in F-36p cells. As2S2 can inhibit proliferation and viability, induce apoptosis, and concurrently promote erythroid differentiation in cytokine-dependent MDS-progressed human leukemia cell line F-36p with complex karyotype including -7. The data suggest that QHP and/or As2S2 could be a potential candidate in the treatment of MDS or MDS/AML even with unfavorable cytogenetics.

In vivo antimalarial activity of crude extracts and solvent fractions of leaves of Strychnos mitis in Plasmodium berghei infected mice.

PubMed

Fentahun, Selamawit; Makonnen, Eyasu; Awas, Tesfaye; Giday, Mirutse

2017-01-05

Malaria is a major public health problem in the world which is responsible for death of millions particularly in sub-Saharan Africa. Today, the control of malaria has become gradually more complex due to the spread of drug-resistant parasites. Medicinal plants are the unquestionable source of effective antimalarials. The present study aimed to evaluate antiplasmodial activity and acute toxicity of the plant Strychnos mitis in Plasmodium berghei infected mice. Standard procedures were employed to investigate acute toxicity and 4-day suppressive effect of crude aqueous and hydro-methanolic extracts of the leaves of Strychnos mitis against P. berghei in Swiss albino mice. Water, n-hexane and chloroform fractions, obtained from crude hydro-methanolic extract, were also tested for their suppressive effect against P. berghei. All crude extracts revealed no obvious acute toxicity in mice up to the highest dose administered (2000 mg/kg). All crude and solvent fractions of the leaves of Strychnos mitis inhibited parasitaemia significantly (p < 0.01). At the highest dose of 600 mg/kg, both aqueous and hydro-methanolic extracts demonstrated higher performance with 95.5 and 93.97% parasitaemia suppression, respectively. All doses of crude extracts and fractions of leaves of Strychnos mitis prolonged survival time of infected mice dose dependently. The highest two doses of the crude aqueous and hydro-methanolic extracts, and chloroform and aqueous fractions prevented weight loss in a dose dependent manner. Whereas, all doses of n-hexane fraction prevented loss of body weight but not in a dose dependent manner. The crude aqueous extract at the doses of 400 mg/kg and 600 mg/kg and hydro-methanolic extract at all dose levels significantly (p < 0.01) prevented packed cell volume reduction. Crude aqueous extract at a dose of 600 mg/kg and hydro-methanolic extract at all dose levels significantly prevented temperature reduction. Phytochemical screening of the crude aqueous and hydro-methanolic extracts revealed the presence of alkaloids, anthraquinones, glycosides, terpenoids, saponins, tannins and phenols. The results of this study provide support the traditional therapeutic use of Strychnos mitis for treatment of malaria. However, further in-depth study is needed to evaluate the potential of the plant towards the development of new antimalarial agent.

Gigantol isolated from the whole plants of Cymbidium goeringii inhibits the LPS-induced iNOS and COX-2 expression via NF-kappaB inactivation in RAW 264.7 macrophages cells.

PubMed

Won, Jong-Heon; Kim, Ji-Yeon; Yun, Kyung-Jin; Lee, Jin-Hee; Back, Nam-In; Chung, Hae-Gon; Chung, Sun A; Jeong, Tae-Sook; Choi, Myung-Sook; Lee, Kyung-Tae

2006-10-01

During our efforts to find bioactive natural products with anti-inflammatory activity, we isolated gigantol from the whole plants of Cymbidium goeringii (Orchidaceae) by activity-guided chromatographic fractionation. Gigantol was found to have potent inhibitory effects on LPS-induced nitric oxide (NO) and prostaglandin E (2) (PGE (2)) production in RAW 264.7 cells. Consistent with these findings, gigantol suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in RAW 264.7 cells in a concentration-dependent manner. Our data also indicate that gigantol is a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) release and influenced the mRNA expression levels of these cytokines in a dose-dependent manner. Furthermore, a reporter gene assay for nuclear factor kappa B (NF-kappaB) and an electromobility shift assay (EMSA) demonstrated that gigantol effectively inhibited the activation of NF-kappaB, which is necessary for the expression of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6. Thus, our studies suggest that gigantol inhibits LPS-induced iNOS and COX-2 expression by blocking NF- kappaB activation.

An EAL domain protein and cyclic AMP contribute to the interaction between the two quorum sensing systems in Escherichia coli.

PubMed

Zhou, Xianxuan; Meng, Xiaoming; Sun, Baolin

2008-09-01

Quorum sensing (QS) is a bacterial cell-cell communication process by which bacteria communicate using extracellular signals called autoinducers. Two QS systems have been identified in Escherichia coli K-12, including an intact QS system 2 that is stimulated by the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex and a partial QS system 1 that consists of SdiA (suppressor of cell division inhibitor) responding to signals generated by other microbial species. The relationship between QS system 1 and system 2 in E. coli, however, remains obscure. Here, we show that an EAL domain protein, encoded by ydiV, and cAMP are involved in the interaction between the two QS systems in E. coli. Expression of sdiA and ydiV is inhibited by glucose. SdiA binds to the ydiV promoter region in a dose-dependent, but nonspecific, manner; extracellular autoinducer 1 from other species stimulates ydiV expression in an sdiA-dependent manner. Furthermore, we discovered that the double sdiA-ydiV mutation, but not the single mutation, causes a 2-fold decrease in intracellular cAMP concentration that leads to the inhibition of QS system 2. These results indicate that signaling pathways that respond to important environmental cues, such as autoinducers and glucose, are linked together for their control in E. coli.

Antioxidant and anticancer activity of Artemisia princeps var. orientalis extract in HepG2 and Hep3B hepatocellular carcinoma cells

PubMed Central

Choi, Eun-Jeong

2013-01-01

Objective The aim of the present study was to investigate antioxidant and the anticancerigen activity of a methanol extract from Artemisia princeps var. orientalis (APME), a well-known traditional herbal medicine in Asia, in hepatocellular cancer cells. Methods To evaluate the antioxidant activity of APME, reactive oxygen species (ROS) and the antioxidant enzymes, superoxide dismutase (SOD) and catalase were investigated in HepG2 cells exposed to APME (5, 100, and 200 µg/mL) for 72 h. Then, to evaluate the anticancer activity of APME, we investigated the proliferation and apoptosis induction of HepG2 and Hep3B cells exposed to APME (1-200 µg/mL) for 24, 48, and 72 h. Results APME dose-dependently reduced the generation of ROS in the presence of H2O2 compared with control cells. Furthermore, it increased catalase and SOD activity. Moreover, APME inhibited cell proliferation in a dose- and time-dependent manner, but at concentrations lower than 100 µg/mL, the inhibition was less dose-dependent than time-dependent. HepG2 and Hep3B cells exposed to 5, 100, and 200 µg/mL APME for 72 h underwent cell cycle arrest and apoptosis. Exposure to APME resulted in a significant increase in the number of cells in G1 phase and a decrease in the G2/M phase cell population. In addition, APME induced P53 expression of HepG2 cells in a dose-dependent manner, and played a role in the downregulation of Bcl-2 and upregulation of Bax in both HepG2 and Hep3B cells. Conclusions These results indicate the potential role of APME as an antioxidant and anticancerigen agent in hepatocarcinoma cell lines. PMID:24255577

Contrasting effects of systemic and central sibutramine administration on the intake of a palatable diet in the rat.

PubMed

Pratt, Wayne E; Connolly, Megan E

2010-10-22

Sibutramine hydrochloride monohydrate is the only centrally active weight-modifying agent currently approved by the FDA for long-term use in the treatment of obesity. Systemic sibutramine treatment has been shown to reduce food intake in humans and rodent models in a manner that is consistent with the enhancement of satiety mechanisms. Although it is generally assumed that the hypophagic effects of the drug are mediated by actions within the brain, the locus or loci of these effects remains unclear. These experiments compared the effects of systemic and intracranial injections of sibutramine on the intake of a palatable diet in non-deprived animals. Consistent with prior reports, systemic injections of sibutramine hydrochloride (at 0, 0.5, 1.0, or 3.0mg/kg sibutramine i.p.) dose-dependently reduced feeding on a high fat/high sucrose diet across a 2-h feeding session, but did not alter water intake or locomotor activity. In contrast, bilateral injections of sibutramine (at 0.0, 2.0, 4.0 and 10.0μg/0.5μl/side) into either the paraventricular nucleus of the hypothalamus (PVN) or the medial nucleus accumbens shell (ACb) significantly and dose-dependently increased food intake of the sweetened fat diet. ACb treatment also modestly inhibited locomotor behavior; intracranial injections had no effect on water consumption. These experiments are the first to suggest that sibutramine treatment may have distinct actions upon separate neural circuits that modulate food intake behavior in the rat. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Characterization and hypoglycemic activity of a β-pyran polysaccharides from bamboo shoot (Leleba oldhami Nakal) shells.

PubMed

Zheng, Yafeng; Zhang, Shuai; Wang, Qi; Lu, Xu; Lin, Liangmei; Tian, Yuting; Xiao, Jianbo; Zheng, Baodong

2016-06-25

The bamboo shoot (Leleba oldhami Nakal) shell is a by-product during bamboo shoot processing. It is a cheap and available resource for dietary polysaccharides. Herein, a novel polysaccharide BSSP2a was isolated and characterized from the bamboo shoot shell polysaccharides, and it was identified as a homogeneous highly-branched beta type pyran polysaccharide with a molecular weight of 1.63×10(4)kDa, which consisted of arabinose, xylose, mannose, glucose and galactose at a molar ratio of 20.4:4.9:1:3.4:20.6. The crude polysaccharides (BSSP) from the bamboo shoots shell showed hypoglycemic activity on the high fat diet and streptozotocin induced diabetic mice in a dose-dependent manner. The administration of high dose BSSP (400mg/kg) improved body weight loss and serum insulin loss, and significantly decreased the blood glucose level, serum triglycerides as well as total cholesterol levels by 48.7%, 34.8% and 26.5%, respectively. The results highlight the potential of the bamboo shoot shell polysaccharides as a natural anti-diabetic agent. Copyright © 2016 Elsevier Ltd. All rights reserved.

Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand.

PubMed

Saralamma, Venu Venkatarame Gowda; Nagappan, Arulkumar; Hong, Gyeong Eun; Lee, Ho Jeong; Yumnam, Silvia; Raha, Suchismita; Heo, Jeong Doo; Lee, Sang Joon; Lee, Won Sup; Kim, Eun Hee; Kim, Gon Sup

2015-09-18

Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies' results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

ENMD-1068, a protease-activated receptor 2 antagonist, inhibits the development of endometriosis in a mouse model.

PubMed

Wang, Yifeng; Lin, Min; Weng, Huinan; Wang, Xuefeng; Yang, Li; Liu, Fenghua

2014-06-01

Protease-activated receptor 2 plays an important role in the pathogenesis of endometriosis. We studied the effect of ENMD-1068, a protease-activated receptor 2 antagonist, on the development of endometriosis in a noninvasive fluorescent mouse model. A red fluorescent protein-expressing xenograft model of human endometriosis was created in nude mice. After endometriosis induction, the mice were injected intraperitoneally with either 25 mg/kg or 50 mg/kg ENMD-1068 or with 200 μL of the vehicle control daily for 5 days. The endometriotic lesions that developed in the mice were then counted, measured, and collected. The lesions were assessed for the production of interleukin 6 and monocyte chemotactic protein-1 by enzyme-linked immunosorbent assays and evaluated for the activation of nuclear factor-κB and the expression of vascular endothelial growth factor by immunohistochemical analyses. Cell proliferation and apoptosis were assessed by immunohistochemistry for Ki-67 and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, respectively. ENMD-1068 dose-dependently inhibited the development of endometriotic lesions (P < .05) without apparent toxicity to various organs of the treated mice. Consistently, ENMD-1068 dose-dependently inhibited the expression of interleukin 6 and nuclear factor-κB (P < .05) and cell proliferation (P < .05) in the lesions, as well as increased the percentage of apoptotic cells (P < .05). ENMD-1068 reduced the levels of monocyte chemotactic protein-1 and vascular endothelial growth factor in the lesions (P < .05), but not in a dose-dependent manner. Our study suggests that ENMD-1068 is effective in suppressing the growth of endometriosis, which might be attributed to the drug's antiangiogenic and antiinflammatory activities. Copyright © 2014 Mosby, Inc. All rights reserved.

Dose-dependent effects of lesogaberan on reflux measures in patients with refractory gastroesophageal reflux disease: a randomized, placebo-controlled study.

PubMed

Miner, Philip B; Silberg, Debra G; Ruth, Magnus; Miller, Frank; Pandolfino, John

2014-11-18

The γ-aminobutyric acid type B-receptor agonist lesogaberan (AZD3355) has been developed for use in patients with gastroesophageal reflux disease (GERD) symptoms despite proton pump inhibitor (PPI) therapy (partial responders). This study aimed to explore the dose-response effect of lesogaberan on reflux episodes in partial responders. In this randomized, single-centre, double-blind, crossover, placebo-controlled study, partial responders taking optimised PPI therapy were given 30, 90, 120 and 240 mg doses of lesogaberan. Each dose was given twice (12 h apart) during a 24-h period, during which impedance-pH measurements were taken. Twenty-five patients were included in the efficacy analysis and 27 in the safety analysis. The effect of lesogaberan on the mean number of reflux episodes was dose-dependent, and all doses significantly reduced the mean number of reflux episodes relative to placebo. Lesogaberan also dose-dependently reduced the mean number of acid reflux episodes (except the 30 mg dose) and weakly acid reflux episodes (all doses) significantly, relative to placebo. Regardless of dose, lesogaberan had a similar effect on the percentage of time with esophageal pH < 4 [mean reduction: 68.5% (30 mg), 54.2% (90 mg), 65.9% (120 mg), 72.1% (240 mg); p < 0.05 except 90 mg dose]. No adverse events led to discontinuation and no serious adverse events occurred during active treatment. Lesogaberan inhibited reflux in a dose-dependent manner in partial responders taking optimised PPI therapy, and these effects were significant versus placebo. All lesogaberan doses were well tolerated and were not associated with clinically relevant adverse events. ClinicalTrials.gov identifier: NCT01043185.

Ethanolic Neem (Azadirachta indica) Leaf Extract Prevents Growth of MCF-7 and HeLa Cells and Potentiates the Therapeutic Index of Cisplatin

PubMed Central

Sharma, Chhavi; Vas, Andrea J.; Goala, Payal; Gheewala, Taher M.; Rizvi, Tahir A.

2014-01-01

The present study was designed to gain insight into the antiproliferative activity of ethanolic neem leaves extract (ENLE) alone or in combination with cisplatin by cell viability assay on human breast (MCF-7) and cervical (HeLa) cancer cells. Nuclear morphological examination and cell cycle analysis were performed to determine the mode of cell death. Further, to identify its molecular targets, the expression of genes involved in apoptosis, cell cycle progression, and drug metabolism was analyzed by RT-PCR. Treatment of MCF-7, HeLa, and normal cells with ENLE differentially suppressed the growth of cancer cells in a dose- and time-dependent manner through apoptosis. Additionally, lower dose combinations of ENLE with cisplatin resulted in synergistic growth inhibition of these cells compared to the individual drugs (combination index <1). ENLE significantly modulated the expression of bax, cyclin D1, and cytochrome P450 monooxygenases (CYP 1A1 and CYP 1A2) in a time-dependent manner in these cells. Conclusively, these results emphasize the chemopreventive ability of neem alone or in combination with chemotherapeutic treatment to reduce the cytotoxic effects on normal cells, while potentiating their efficacy at lower doses. Thus, neem may be a prospective therapeutic agent to combat gynecological cancers. PMID:24624140

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

PubMed

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

2010-12-01

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

Red-koji fermented red ginseng ameliorates high fat diet-induced metabolic disorders in mice.

PubMed

Kim, Chang Man; Yi, Seong Joon; Cho, Il Je; Ku, Sae Kwang

2013-10-30

Fermentation of medicinal herbs improves their pharmacological efficacy. In this study, we investigated the effects of red-koji fermented red ginseng (fRG) on high-fat diet (HFD)-mediated metabolic disorders, and those effects were compared to those of non-fermented red ginseng (RG). fRG (500, 250 or 125 mg/kg), RG (250 mg/kg), simvastatin (10 mg/kg), silymarin (100 mg/kg) and metformin (250 mg/kg) were orally administered from 1 week after initiation of HFD supply for 84 days. The diameter of adipocytes in periovarian and abdominal fat pads and the thickness of the abdominal fat were significantly decreased by fRG treatment, while HFD-mediated weight gain was partly alleviated by fRG in a dose-dependent manner. Moreover, biochemical and histomorphometrical analyses clearly indicated that fRG significantly inhibited HFD-induced metabolic disorders such as hyperglycemia, hyperlipidemia, hepatopathy and nephropathy in a dose-dependent manner. More favorable pharmacological effects on HFD-mediated metabolic disorders were also observed with fRG compared to an equal dose of RG. This finding provides direct evidence that the pharmacological activities of RG were enhanced by red-koji fermentation, and fRG could be a neutraceutical resource for the alleviation of obesity-mediated metabolic disorders.

A study of normoxic polymer gel using monomer 2-hydroxyethyl methacrylate (HEMA)

NASA Astrophysics Data System (ADS)

Ishak, Siti Atiqah; Mustafa, Iskandar Shahrim; Rahman, Azhar Abdul; Moktar, Mohd; Min, Ung Ngie

2015-04-01

The aim of this study is to determine the sensitivity of HEMA-polymer gel mixture consist of monomer 2-hydroxyethyl methacrylate (HEMA) with different types of composition. Several composition of HEMA-polymer gel were fabricated and the gels were irradiated with radiation dose between 10 cGy to 100cGy by using x-ray machine and 100 cGy to 1400 cGy by using 6 MV photon beam energy of linear accelerator. The degree of polymerization was evaluated by using magnetic resonance imaging (MRI) with dependence of R2-dose response. Polymer gel consists of cross-linker, anti-oxidant Tetrakis(Hydroxymethyl)phosphonium chloride solution (THPC) and oxygen scavenger hydroquinone shows a stable sensitivity with highest dose dependency. Besides, the results shows the stage polymerization consist of induction, propagation, termination, and chain transfer were dependence with type of chemical mixture and radiation dose. Thus, normoxic HEMA-polymer gel with the different gel formulations can have a better dose resolution and an appropriate recipe must be selected to increase of the sensitivity required and the stability of the dosimeter.

A study of normoxic polymer gel using monomer 2-hydroxyethyl methacrylate (HEMA)

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

Ishak, Siti Atiqah; Mustafa, Iskandar Shahrim; Rahman, Azhar Abdul

2015-04-24

The aim of this study is to determine the sensitivity of HEMA-polymer gel mixture consist of monomer 2-hydroxyethyl methacrylate (HEMA) with different types of composition. Several composition of HEMA-polymer gel were fabricated and the gels were irradiated with radiation dose between 10 cGy to 100cGy by using x-ray machine and 100 cGy to 1400 cGy by using 6 MV photon beam energy of linear accelerator. The degree of polymerization was evaluated by using magnetic resonance imaging (MRI) with dependence of R2-dose response. Polymer gel consists of cross-linker, anti-oxidant Tetrakis(Hydroxymethyl)phosphonium chloride solution (THPC) and oxygen scavenger hydroquinone shows a stable sensitivitymore » with highest dose dependency. Besides, the results shows the stage polymerization consist of induction, propagation, termination, and chain transfer were dependence with type of chemical mixture and radiation dose. Thus, normoxic HEMA-polymer gel with the different gel formulations can have a better dose resolution and an appropriate recipe must be selected to increase of the sensitivity required and the stability of the dosimeter.« less

Dietary intake of high-dose biotin inhibits spermatogenesis in young rats.

PubMed

Sawamura, Hiromi; Ikeda, Chieko; Shimada, Ryoko; Yoshii, Yui; Watanabe, Toshiaki

2015-02-01

To characterize a new function of the water-soluble vitamin, biotin, in reproduction and early growth in mammals, the effects of high dietary doses of biotin on early spermatogenesis were biochemically and histologically investigated in male rats. Weaned rats were fed a CE-2 (control) diet containing 0.00004% biotin, or a control diet supplemented with 0.01%, 0.1%, or 1.0% biotin. Pair-fed rats were fed a control diet that was equal in calories to the amount ingested by the 1.0% biotin group, because food intake was decreased in the 1.0% biotin group. Food intake and body weight gain were lower in the 1.0% biotin group than in the control group. The kidney, brain and testis weights were significantly lower in the 1.0% biotin group than in the pair-fed group after 6 weeks of feeding. The accumulation of biotin in the liver and testis increased in a dose-dependent manner. In the 1.0% biotin group, the number of mature sperm was markedly lower, that of sperm with morphologically abnormal heads, mainly consisting of round heads, had increased. In addition, the development of seminiferous tubules was inhibited, and few spermatogonia and no spermatocytes were histologically observed. These results demonstrated that the long-term intake of high-dose biotin inhibited spermatogenesis in young male rats. © 2014 Japanese Teratology Society.

Dose-response relations between second-hand smoke exposure and depressive symptoms among middle-aged women.

PubMed

Ye, Xiaohua; Li, LiXia; Gao, Yanhui; Zhou, Shudong; Yang, Yi; Chen, Sidong

2015-09-30

A growing body of evidence indicates a strong association between smoking and depression. However, little is known about the possible effects of second-hand smoke (SHS) exposure on depression. This study aimed to examine the potential dose-response relation between SHS exposure and depressive symptoms among non-smoking middle-aged women. A cross-sectional survey was conducted using a stratified three-stage sampling method. Depressive symptoms were measured by the Center for Epidemiologic Studies Depression Scale with a cut-off point of 16. Self-reported SHS exposure was defined as non-smokers׳ inhalation of the smoke exhaled from smokers on at least one day a week. The multivariable logistic regression analysis was completed with adjustment for potential confounders. Among 1280 middle-aged women, 19.4% were classified as having depressive symptoms. There was a 104% increased odds of depressive symptoms corresponding to SHS exposure in general (OR=2.04, 95% CI 1.48-2.79) using no exposure as reference. There were significant positive relations between SHS exposure in general and depressive symptoms in a dose-response manner. These significant trends were observed consistently whether SHS exposure occurred in homes or workplaces. Our findings suggest that long-term and regular SHS exposure is associated with a significant, dose-dependent increase in risk of depressive symptoms. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effect of intracellular photosensitized singlet oxygen production on the electrophysiological properties of cultured rat hippocampal neurons.

PubMed

Breitenbach, Thomas; Ogilby, Peter R; Lambert, John D C

2010-12-01

Whole-cell patch-clamp recordings from single cultured mammalian neurons have been used to provide insight into early membrane-dependent events that result upon the intracellular photosensitized production of singlet molecular oxygen, O(2)(a(1)Δ(g)). The singlet oxygen sensitizers used, pyropheophorbide a (PPa) and protoporphyrin IX (PpIX), locate mainly in cell membranes and mitochondria, respectively. Irradiation of these sensitizers altered both passive and dynamic electrophysiological properties of the neurons in a dose-dependent manner, though the response threshold was much lower with PPa than with PpIX. In particular, notable decreases were observed in the rising and falling rates of action potentials and, at higher light fluences, plateau potentials consistent with activation of Ca(2+) channels also developed. The data suggest that singlet oxygen production specifically influences Na(+), K(+) and Ca(2+) ionophores in the cell membrane. Upon terminating sensitizer irradiation, responses evoked by PPa stabilized immediately whereas those evoked by PpIX continued to develop. These data are consistent with a spatially-resolved sphere of intracellular singlet oxygen activity. While the response to PPa irradiation appears to be membrane specific, the response to PpIX irradiation appears to be systemic and possibly part of a cascade of apoptotic events. These results should contribute to a better understanding of membrane-dependent events pertinent to cell death mediated by singlet oxygen.

Cardiac safety of lacosamide: the non-clinical perspective.

PubMed

Delaunois, A; Colomar, A; Depelchin, B O; Cornet, M

2015-11-01

Lacosamide is indicated for the adjunctive treatment of partial-onset seizures in adult patients. Unlike other sodium channel-blocking antiepileptic drugs, lacosamide selectively enhances sodium channel slow inactivation. Potential effects of lacosamide on cardiac sodium channels and their cardiovascular consequences were comprehensively assessed. This manuscript presents the non-clinical cardiac safety profile of lacosamide. Lacosamide was tested in vitro on sodium and L-type calcium currents from isolated human atrial myocytes and on hERG-mediated potassium currents from stably transfected HEK293 cells. Cardiac action potentials were recorded in guinea pig ventricular myocytes. In vivo, hemodynamic and ECG parameters were evaluated in anesthetized dogs and monkeys receiving acute cumulative intravenous doses of lacosamide. Following intravenous dosing with lacosamide, dose-dependent PR and QRS prolongation and ECG abnormalities (loss of P waves, atrioventricular and intraventricular blocks, junctional premature contractions) were observed in anesthetized dogs and monkeys. In vitro, lacosamide reduced human cardiac sodium currents in a concentration-, voltage- and state-dependent manner. Lacosamide reductions in Vmax in guinea pig myocytes were similar to lamotrigine and carbamazepine. Lacosamide showed no relevant inhibitory effects on hERG and L-type calcium channels and did not prolong QTc in vivo. ECG findings in anesthetized animals correlate well with in vitro sodium channel-related effects and are also consistent with those (PR prolongation, first-degree atrioventricular block) reported in healthy volunteers and patients with epilepsy. Both in vivo and in vitro effects were detected from exposure levels 1.5- to 2-fold above those achieved with the maximum-recommended human lacosamide dose (400 mg/day). © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Force properties of skinned cardiac muscle following increasing volumes of aerobic exercise in rats.

PubMed

Boldt, Kevin Rudi; Rios, Jaqueline Lourdes; Joumaa, Venus; Herzog, Walter

2018-05-03

The positive effects of chronic endurance exercise training on health and performance have been well documented. These positive effects have been evaluated primarily at the structural level, and work has begun to evaluate mechanical adaptations of the myocardium. However, it remains poorly understood how the volume of exercise training affects cardiac adaptation. In order to gain some understanding, we subjected three-month-old Sprague-Dawley rats (N=23) to treadmill running for eleven weeks at one of three exercise volumes (moderate, high, and extra high). Following training, hearts were excised and mechanical testing was completed on skinned trabecular fiber bundles. Performance on a maximal fitness test was dose-dependent upon training volume, where greater levels of training led to greater performance. No differences were observed between animals from any group for active stress production. Heart mass and passive stress increases in a dose-dependent manner for animals in the control, moderate, and high duration groups. However, hearts from animals in the extra high duration group presented with inhibited responses for heart mass and passive stress, despite performing greatest on a graded treadmill fitness test. These results suggest that heart mass and passive stress adapt in a dose-dependent manner, until exercise becomes excessive and adaptation is inhibited. Our findings are in agreement with the beneficial role exercise has in cardiac adaptation. However, excessive exercise comes with risks of maladaptation which must be weighed against the desire to increase performance.

Adiponectin influences progesterone production from MA-10 Leydig cells in a dose-dependent manner.

PubMed

Landry, David; Paré, Aurélie; Jean, Stéphanie; Martin, Luc J

2015-04-01

Obesity in men is associated with lower testosterone levels, related to reduced sperm concentration and the development of various diseases with aging. Hormones produced by the adipose tissue may have influences on both metabolism and reproductive function. Among them, the production and secretion of adiponectin is inversely correlated to total body fat. Adiponectin receptors (AdipoR1 and AdipoR2) have been found to be expressed in testicular Leydig cells (producing testosterone). Since StAR and Cyp11a1 are essential for testosterone synthesis and adiponectin has been shown to regulate StAR mRNA in swine granulosa cells, we hypothesized that adiponectin might also regulate these genes in Leydig cells. Our objective was to determine whether adiponectin regulates StAR and Cyp11a1 genes in Leydig cells and to better define its mechanisms of action. Methods used in the current study are qPCR for the mRNA levels, transfections for promoter activities, and enzyme-linked immunosorbent assay for the progesterone concentration. We have found that adiponectin cooperates with cAMP-dependent stimulation to activate StAR and Cyp11a1 mRNA expressions in a dose-dependent manner in MA-10 Leydig cells as demonstrated by transfection of a luciferase reporter plasmid. These results led to a significant increase in progesterone production from MA-10 cells. Thus, our data suggest that high doses of adiponectin typical of normal body weight may promote testosterone production from Leydig cells.

In vitro effects of diethylstilbestrol, genistein, 4-tert-butylphenol, and 4-tert-octylphenol on steroidogenic activity of isolated immature rat ovarian follicles

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

Myllymaeki, Sari; Haavisto, Tapio; Vainio, Minna

2005-04-01

Isolated rat ovarian follicles grow and produce steroid hormones in vitro and so provide a good model for studying the effects of hormonally active compounds on follicular steroidogenesis. We have evaluated the effects of diethylstilbestrol (DES), genistein (GEN) and two alkylphenols, 4-tert-butylphenol (BP) and 4-tert-octylphenol (OP) on the growth, survival, and steroid hormone and cAMP production by isolated 14-day-old rat (Sprague-Dawley) ovarian follicles. During a 5-day culture, FSH was obligatory for follicle growth and increased estradiol and testosterone secretion in a dose-dependent manner. DES (10{sup -6} M) caused the strongest decline in estradiol and testosterone levels but did not havemore » detectable effects on either cAMP production or aromatase enzyme activity. GEN caused a prominent decrease in cAMP and testosterone levels without significant changes in secreted estradiol. The latter, apparently, was due to a dose-dependent stimulation of aromatase enzyme activity in the presence of genistein. Both BP and OP decreased estradiol and testosterone secretion in a dose-dependent manner while no effect on aromatase activity was observed. OP, unlike BP, decreased forskolin-induced cAMP levels. Xenoestrogens at the used concentrations did not interfere with the growth and survival of the follicles. The results indicate that isolated ovarian follicles representing intact morphological and functional units offer a sensitive model system for elucidating the female-specific reproductive effects of environmental chemicals.« less

Pharmacokinetics of escin Ia in rats after intravenous administration.

PubMed

Wu, Xiu-Jun; Cui, Xiang-Yong; Tian, Lian-tian; Gao, Feng; Guan, Xin; Gu, Jing-Kai

2014-10-28

Escin, a natural mixture of triterpene saponins, is commonly utilized for the treatment of chronic venous insufficiency, hemorrhoids, inflammation and edema. Escin Ia is the chief active ingredient in escin and plays key role in mediating its pharmacological effects. Adequate pharmacokinetic data are essential for proper application of escin agent in clinical practice. However, pharmacokinetic properties of escin Ia are still poorly understood and this conflicts with the growing use of escin agent over the years. The goal of this study is to investigate the pharmacokinetic behavior of escin Ia in rats after low, medium and high-dose intravenous administration. Wistar rats were divided into 3 groups (n=6 per group) and escin Ia was administered via the caudal vein at doses of 0.5, 1.0 and 2.0 mg/kg, respectively. Subsequently, the concentrations of escin Ia and its metabolite isoescin Ia, a positional isomer of escin Ia, in rats׳ plasma were measured by an established liquid chromatography tandem mass spectrometry (LC-MS/MS) method at various time points following the administration of the drug. Main pharmacokinetic parameters were calculated by non-compartmental analysis using the TopFit 2.0 software package (Thomae GmbH, Germany). After intravenous administration, the Cmax and AUC of escin Ia increased in a dose-proportional manner at the dose of 0.5 mg/kg and 1.0 mg/kg, while increased in a more than dose-proportional manner at the doses of 1.0 mg/kg and 2.0 mg/kg. The t₁/₂ was significantly longer with increased intravenous doses, while other parameters such as CL and Vd also exhibit disagreement among three doses. Taken together, our data showed dose-dependent pharmacokinetic profile of escin Ia in rats after intravenous administration at the doses of 0.5-2.0 mg/kg. After intravenous administration, escin Ia was rapidly and extensively converted to isoescin Ia. The results suggested dose-dependent pharmacokinetics of escin Ia at the doses of 0.5-2.0 mg/kg after intravenous administration. Escin Ia is isomerized to isoescin Ia rapidly and extensively regardless of the doses. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Direct interaction between caffeic acid phenethyl ester and human neutrophil elastase inhibits the growth and migration of PANC-1 cells.

PubMed

Duan, Jianhui; Xiaokaiti, Yilixiati; Fan, Shengjun; Pan, Yan; Li, Xin; Li, Xuejun

2017-05-01

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignant tumors of the digestive system, but the mechanisms of its development and progression are unclear. Inflammation is thought to be fundamental to pancreatic cancer development and caffeic acid phenethyl ester (CAPE) is an active component of honey bee resin or propolis with anti-inflammatory and anticancer activities. We investigated the inhibitory effects of CAPE on cell growth and migration induced by human neutrophil elastase (HNE) and report that HNE induced cancer cell migration at low doses and growth at higher doses. In contrast, lower CAPE doses inhibited migration and higher doses of CAPE inhibited the growth induced by HNE. HNE activity was significantly inhibited by CAPE (7.5-120 µM). Using quantitative real-time PCR and western blotting, we observed that CAPE (18-60 µM) did not affect transcription and translation of α1-antitrypsin (α1-AT), an endogenous HNE inhibitor. However, in an in silico drug target docking model, we found that CAPE directly bound to the binding pocket of HNE (25.66 kcal/mol) according to CDOCKER, and the residue of the catalytic site stabilized the interaction between CAPE and HNE as evidenced by molecular dynamic simulation. Response unit (RU) values of surface plasmon resonance (SPR) significantly increased with incremental CAPE doses (7.5-120 µM), indicating that CAPE could directly bind to HNE in a concentration-dependent manner. Thus, CAPE is an effective inhibitor of HNE via direct interaction whereby it inhibits the migration and growth of PANC-1 cells in a dose-dependent manner.

Tier-2 studies on monocrotaline immunotoxicity in C57BL/6 mice.

PubMed

Deyo, J A; Kerkvliet, N I

1991-01-01

Monocrotaline (MCT) is a member of a class of naturally occurring phytotoxins known as pyrrolizidine alkaloids, and is a toxicological concern to both man and his livestock. The purpose of these studies was to evaluate the effect of a 14-day oral MCT (0-100 mg/kg per day) exposure on the functional integrity of various immunocyte effector systems in C57BL/6 mice, as well as to investigate potential mechanisms for its immunotoxicity. Decreases in lymphoid organ weights and cellularity, and resident peritoneal exudate cell (PEC) number were only observed after exposure to the highest dose of 100 mg/kg MCT. This dose also inhibited NK cell cytotoxicity, while the total number of NK lytic units per spleen was decreased (-53%) after exposure to 50 mg/kg MCT. Following i.p. injection of SRBC, the percentage of PEC macrophages containing engulfed SRBC was significantly increased in MCT-exposed mice, while the percentage of large vacuolated (activated) macrophages was decreased in a dose-dependent manner. Exposure to MCT significantly decreased the total number of Ig+ cells without altering the number of CD4+ and CD8+ cells. The antibody responses (PFC/10(6) spleen cells) to two T cell-independent antigens, TNP-LPS and DNP-Ficoll, were significantly decreased at all MCT doses, and the degree of suppression of both responses was identical at coincident doses. MCT exposure (25 mg/kg) significantly suppressed the blastogenic response to the T cell mitogen concanavalin A (-38%), and to the B cell mitogen lipopolysaccharide (-58%). These results indicate that exposure to MCT can alter the functional integrity of various immune effector responses in a dose-dependent manner, and suggest that the B cell may be a relatively more sensitive target of MCT immunotoxicity compared to T cells, macrophages and NK cells.

Effects of UV-B irradiation on isoforms of antioxidant enzymes and their activities in red alga Grateloupia filicina (Rhodophyta)

NASA Astrophysics Data System (ADS)

Zhao, Jiqiang; Li, Lixia

2014-11-01

Macroalgae in a littoral zone are inevitably exposed to UV-B irradiance. We analyzed the effects of UV-B on isoenzyme patterns and activities of superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), and ascorbate peroxidase (APX) of red algae Grateloupia filicina (Lamour.) C. Agardh. The activities of SOD, CAT, and APX changed in response to UV-B in a time- and dose-dependent manner. POX activity increased significantly under all three UV-B treatments. The enzymatic assay showed three distinct bands of SODI (Mn-SOD), SODII (Fe-SOD), and SODIII (CuZn-SOD) under a low (Luv) and medium (Muv) dose of UV-B irradiation, while SODI and SODIII activities decreased significantly when exposed to a high dose of UV-B irradiation (Huv). The activity of POX isoenzymes increased significantly after exposure to UV-B, which is consistent with the total activity. In addition, a clear decrease in activity of CATIV was detected in response to all the three doses of UV treatments. Some bands of APX isoenzyme were also clearly influenced by UV-B irradiation. Correspondingly, the daily growth rate declined under all the three exposure doses, and was especially significant under Muv and Huv treatments. These data suggest that, although the protection mechanisms of antioxidant defense system are partly inducible by UV-B to prevent the damage, G. filicina has incomplete tolerance to higher UV-B irradiation stress.

4-aminopyridine, a Kv channel antagonist, prevents apoptosis of rat cerebellar granule neurons.

PubMed

Hu, Chang-Long; Liu, Zheng; Zeng, Xi-Min; Liu, Zi-Qiang; Chen, Xian-Hua; Zhang, Zhi-Hong; Mei, Yan-Ai

2006-09-01

Compelling evidence indicates that excessive potassium (K+) efflux and intracellular K+ depletion are the key early steps in apoptosis. Previously, we reported that apoptosis of cerebellar granule neurons induced by incubation in low-K+ (5 mM) and serum-free medium was associated with an increase in A-type transient inactivation of K+ channel current (IA) amplitude and modulation of channels' gating properties. Here, we showed that a classic K+ channel blocker, 4-aminopyradine (4-AP), significantly inhibited IA amplitude in a concentration-dependent manner (reduction of current by 10 microM and 10 mM 4-AP was 11.4+/-1.3% and 72.2+/-3.3%, respectively). Moreover, 4-AP modified the steady-state activation and inactivation kinetics of IA channels, such that the activation and inactivation curves were shifted to the right about 20 mV and 17 mV, respectively. Fluorescence staining showed that 4-AP dramatically increased the viability of cells undergoing apoptosis in a dose-dependent manner. That is, while 5 mM 4-AP was present, cell viability was 84.9+/-5.2%. Consistent with the cell viability analysis, internucleosomal DNA fragmentation by gel electrophoresis analysis showed that 5 mM 4-AP also protected against neuronal apoptosis. Furthermore, 4-AP significantly inhibited cytochrome c release and caspase-3 activity induced by low-K+/serum-free incubation. Finally, current-clamp analysis indicated that 5 mM 4-AP did not significantly depolarize the membrane potential. These results suggest that 4-AP has robust neuroprotective effects on apoptotic granule cells. The neuroprotective effect of 4-AP is likely not due to membrane depolarization, but rather that 4-AP may modulate the gating properties of IA channels in an anti-apoptotic manner.

Modulation of inflammatory bowel disease in a mouse model following infection with Trichinella spiralis

USDA-ARS?s Scientific Manuscript database

Infection of mice with Trichinella spiralis redirects the mucosal immune system from a Th1 to a protective Th2 response with a reduction in the severity of trinitrobenzesulfonic acid-induced colonic damage. T. spiralis infection induced IL-10 production in a dose-dependent manner in oxazolone (OXZ)-...

Wnt/β-catenin signaling enhances osteoblastogenic differentiation from human periodontal ligament fibroblasts.

PubMed

Heo, Jung Sun; Lee, Seung-Youp; Lee, Jeong-Chae

2010-11-01

Wnt/β-catenin signaling has been known to influence bone formation and homeostasis. In this study, we investigated the canonical Wnt signaling regulation of osteogenic differentiation from periodontal ligament (PDL) fibroblasts. Stimulating PDL fibroblasts with lithium chloride (LiCl), a canonical Wnt activator, significantly increased mineralized nodule and alkaline phosphatase (ALP) activity in a time- and dose-dependent manner. LiCl up-regulated protein expression of osteogenic transcription factors, including the runt-related gene 2, Msx2, and Osterix 2, in the PDL fibroblasts. Treatment of these cells with LiCl also increased the mRNA levels of ALP, FosB, and Fra1 in a dose-dependent manner. Blockage of canonical Wnt signaling by treating the cells with DKK1 inhibited Wnt1-stimulated mRNA expression of these osteogenic factors. Furthermore, pretreatment with DKK1 reduced the ALP activity and matrix mineralization stimulated by Wnt1. Collectively, these results suggest that canonical Wnt signaling leads to the differentiation of PDL fibroblasts into osteogenic lineage with the attendant stimulation of osteogenic transcription factors.

NANOPARTICLE DELIVERED BIOSENSOR FOR REACTIVE OXYGEN SPECIES IN DIABETES

PubMed Central

Prow, Tarl W.; Bhutto, Imran; Grebe, Rhonda; Uno, Koichi; Merges, Carol; Mcleod, D. Scott; Lutty, Gerard A.

2008-01-01

The cell’s own antioxidant response element (ARE) can be used to evaluate the complications of diabetes mellitus. The hypothesis that a synthetic ARE could be used as a genetic switch, or biosensor, to turn on and off therapeutic genes is tested herein. Mitochondrial oxidative stress (MOS) has been hypothesized as one of the earliest insults in diabetes. Fluorescent probes used to monitor MOS revealed that the addition of glucose at physiological levels to cultures of endothelial cells was able to induce MOS above normal levels and in a dose dependant manner. Additional data showed that increased glucose levels activated the ARE-GFP in a dose dependant manner. These data support the hypothesis that the induction of MOS is more sensitive to hyperglycemia than the induction of the ARE. Delivery of an ARE-GFP construct with nanoparticles to the eye was successful using sub-retinal injection. This ARE-GFP/nanoparticle construct was functional and reported the activation of the ARE in diabetic rat retinal pigment epithelium (RPE). These data support the use of nanoparticle delivered biosensors for monitoring the oxidative status of tissues in vivo. PMID:18252237

Nanoparticle-delivered biosensor for reactive oxygen species in diabetes.

PubMed

Prow, Tarl W; Bhutto, Imran; Grebe, Rhonda; Uno, Koichi; Merges, Carol; McLeod, D Scott; Lutty, Gerard A

2008-02-01

The cell's own antioxidant response element (ARE) can be used to evaluate the complications of diabetes mellitus. The hypothesis that a synthetic ARE could be used as a genetic switch, or biosensor, to turn on and off therapeutic genes is tested herein. Mitochondrial oxidative stress (MOS) has been hypothesized as one of the earliest insults in diabetes. Fluorescent probes used to monitor MOS revealed that the addition of glucose at physiological levels to cultures of endothelial cells was able to induce MOS above normal levels and in a dose-dependant manner. Additional data showed that increased glucose levels activated the ARE-GFP in a dose-dependant manner. These data support the hypothesis that the induction of MOS is more sensitive to hyperglycemia than the induction of the ARE. Delivery of an ARE-GFP construct with nanoparticles to the eye was successful using sub-retinal injection. This ARE-GFP/nanoparticle construct was functional and reported the activation of the ARE in diabetic rat retinal pigment epithelium (RPE). These data support the use of nanoparticle-delivered biosensors for monitoring the oxidative status of tissues in vivo.

β-Amino-n-butyric Acid Regulates Seedling Growth and Disease Resistance of Kimchi Cabbage

PubMed Central

Kim, Yeong Chae; Kim, Yeon Hwa; Lee, Young Hee; Lee, Sang Woo; Chae, Yun-Soek; Kang, Hyun-Kyung; Yun, Byung-Wook; Hong, Jeum Kyu

2013-01-01

Non-protein amino acid, β-amino-n-butyric acid (BABA), has been involved in diverse physiological processes including seedling growth, stress tolerance and disease resistance of many plant species. In the current study, treatment of kimchi cabbage seedlings with BABA significantly reduced primary root elongation and cotyledon development in a dose-dependent manner, which adverse effects were similar to the plant response to exogenous abscisic acid (ABA) application. BABA was synergistically contributing ABA-induced growth arrest during the early seedling development. Kimchi cabbage leaves were highly damaged and seedling growth was delayed by foliar spraying with high concentrations of BABA (10 to 20 mM). BABA played roles differentially in in vitro fungal conidial germination, mycelial growth and conidation of necrotroph Alternaria brassicicola causing black spot disease and hemibiotroph Colletotrichum higginsianum causing anthracnose. Pretreatment with BABA conferred induced resistance of the kimchi cabbage against challenges by the two different classes of fungal pathogens in a dose-dependent manner. These results suggest that BABA is involved in plant development, fungal development as well as induced fungal disease resistance of kimchi cabbage plant. PMID:25288957

18β-glycyrrhetinic acid inhibits migration and invasion of human gastric cancer cells via the ROS/PKC-α/ERK pathway.

PubMed

Cai, Hongke; Chen, Xi; Zhang, Jianbo; Wang, Jijian

2018-01-01

18β-glycyrrhetinic acid (18β-GA) is a bioactive component of licorice root which exerts pharmacological activities including anti-inflammatory, antiviral, anti-oxidative and anti-cancer effects. The current study further investigated the molecular mechanisms associated with the inhibitory effects of 18β-GA on tumor metastasis in human gastric cancer cells. The results indicated that 18β-GA significantly reduced invasion and migration activities and suppressed MMP-2 and 9 activities on SGC-7901cells in a dose-dependent manner. Further study showed 18β-GA upregulated E-cadherin expression but downregulated vimentin expression. The results also showed that 18β-GA inhibited ROS formation, PKC-α expression and the phosphorylation of ERK in a dose-dependent manner. In conclusion, this study revealed that 18β-GA inhibits migration and invasion via the ROS/PKC-α/ERK signaling pathway in gastric cancer cells. This suggests that 18β-GA has the potential to be used as an effective chemopreventive agent for the prevention of gastric cancer metastasis.

Delayed adverse effects of neonatal exposure to diethylstilbestrol and their dose dependency in female rats.

PubMed

Yoshida, Midori; Takahashi, Miwa; Inoue, Kaoru; Hayashi, Seigo; Maekawa, Akihiko; Nishikawa, Akiyoshi

2011-08-01

Neonatal exposure to estrogenic chemicals causes irreversible complex damage to the hypothalamus-pituitary-gonadal axis and reproductive system in females. Some lesions are noted after maturation as delayed adverse effects. We investigated the characteristics and dose dependence of delayed effects using female rats neonatally exposed to diethylstilbestrol (DES). Female Donryu rats were subcutaneously injected with a single dose of DES of 0 (control), 0.15, 1.5, 15, 150, or 1,500 µg/kg bw after birth. All except the lowest dose had estrogenic activity in a uterotrophic assay. All rats at 1500 µg/kg and some at 150 µg/kg showed abnormal morphologies in the genital tract, indicating they were androgenized before maturation. Although no morphological abnormalities were noted at 15 µg/kg or lower, onset of persistent estrus was significantly accelerated in the 1.5, 15, and 150 µg/kg groups with dose dependency, and the latest onset was from seventeen to twenty-one weeks of age at 1.5 µg/kg. The neonatal exposure to DES increased uterine adenocarcinoma development only at 150 µg/kg, although uterine anomalies were detected at 1,500 µg/kg. These results indicate that neonatal exposure to DES, which exerts estrogenic activity in vivo, induces delayed adverse effects in female rats in a dose-dependent manner. Early onset of persistent estrus appears to be the most sensitive parameter.

Deferasirox at therapeutic doses is associated with dose-dependent hypercalciuria.

PubMed

Wong, Phillip; Polkinghorne, Kevan; Kerr, Peter G; Doery, James C G; Gillespie, Matthew T; Larmour, I; Fuller, Peter J; Bowden, Donald K; Milat, Frances

2016-04-01

Deferasirox is an oral iron chelator used widely in the treatment of thalassemia major and other transfusion-dependent hemoglobinopathies. Whilst initial long-term studies established the renal safety of deferasirox, there are now increasing reports of hypercalciuria and renal tubular dysfunction. In addition, urolithiasis with rapid loss of bone density in patients with β thalassemia major has been reported. We conducted a cross-sectional cohort study enrolling 152 adult patients comprising of β thalassemia major (81.5%), sickle cell disease (8%), thalassemia intermedia (2%), HbH disease (6.5%) and E/β thalassemia (2%). Cases were matched with normal control subjects on age, gender and serum creatinine. Iron chelator use was documented and urine calcium to creatinine ratios measured. At the time of analysis, 88.8% of patients were receiving deferasirox and 11.2% were on deferoxamine. Hypercalciuria was present in 91.9% of subjects on deferasirox in a positive dose-dependent relationship. This was not seen with subjects receiving deferoxamine. At a mean dose of 30.2±8.8mg/kg/day, deferasirox was associated with an almost 4 fold increase in urine calcium to creatinine ratio (UCa/Cr). Hypercalciuria was present at therapeutic doses of deferasirox in a dose-dependent manner and warrants further investigation and vigilance for osteoporosis, urolithiasis and other markers of renal dysfunction. Copyright © 2016 Elsevier Inc. All rights reserved.

Modulation of desensitization at glutamate receptors in isolated crucian carp horizontal cells by concanavalin A, cyclothiazide, aniracetam and PEPA.

PubMed

Shen, Y; Lu, T; Yang, X L

1999-03-01

In horizontal cells freshly dissociated from crucian carp (Carassius auratus) retina, we examined the effects of modulators of glutamate receptor desensitization, concanavalin A, cyclothiazide, aniracetam and 4-[2-(phenylsulfonylamino)ethylthio]-2,6-difluoro-phenoxyacetam ide (PEPA), on responses to rapid application of glutamate and kainate, using whole-cell voltage-clamp techniques. Incubation of concanavalin A suppressed the peak response but weakly potentiated the equilibrium response of horizontal cells to glutamate. Cyclothiazide blocked glutamate-induced desensitization in a dose-dependent manner, which resulted in a steady increase of the equilibrium current. The concentration of cyclothiazide causing a half-maximal potentiation for the equilibrium response was 85 microM. Furthermore, cyclothiazide shifted the dose-response relationship of the equilibrium current to the right, but slightly suppressed the kainate-induced sustained current. These effects of concanavalin A and cyclothiazide are consistent with the supposition that glutamate receptors of carp horizontal cells may be an alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)-preferring subtype. In order to further characterize the AMPA receptors of horizontal cells, modulation by aniracetam and PEPA of glutamate- and kainate-induced currents was studied. Aniracetam, a preferential modulator of flop variants of AMPA receptors, considerably blocked desensitization of glutamate-induced currents, but only slightly potentiated kainate-induced currents. It was further found that PEPA, a flop-preferring allosteric modulator of AMPA receptor desensitization, slightly suppressed the peak current, while it dramatically potentiated the equilibrium current induced by glutamate in a dose-dependent manner. PEPA was much potent than aniracetam at these receptors and showed the effect on glutamate-induced desensitization even at a concentration as low as 3 microM. PEPA also potentiated non-desensitizing currents induced by kainate, but with much less extent. These modulatory effects of concanavalin A, cyclothiazide, aniracetam and PEPA on AMPA receptors in carp horizontal cells were rather similar to those obtained at AMPA receptors assembled from flop variants expressed in Xenopus oocyte and HEK cell. Consequently, we speculate that the AMPA receptor on carp horizontal cells may predominantly carry the flop splice variants.

Antihyperglycemic effect of syringaldehyde in streptozotocin-induced diabetic rats.

PubMed

Huang, Chia-Hsin; Chen, Mei-Fen; Chung, Hsien-Hui; Cheng, Juei-Tang

2012-08-24

The antihyperglycemic effect of syringaldehyde (1), purified from the stems of Hibiscus taiwanensis, was investigated in streptozotocin-induced diabetic rats (STZ-diabetic rats) showing type-1 like diabetes mellitus. Bolus intravenous injection of 1 showed antihyperglycemic activity in a dose-dependent manner in STZ-diabetic rats. An effective dose of 7.2 mg/kg of 1 attenuated significantly the increase of plasma glucose induced by an intravenous glucose challenge test in normal rats. A glucose uptake test showed that 1 exhibits an increase of glucose uptake activity in a concentration-related manner. Moreover, an effect by 1 was shown for insulin sensitivity in STZ-diabetic rats. The compound was found to increase insulin sensitivity in STZ-diabetic rats. These results suggest that syringaldehyde (1) can increase glucose utilization and insulin sensitivity to lower plasma glucose in diabetic rats.

Protective effect of chelerythrine against ethanol-induced gastric ulcer in mice.

PubMed

Li, Wei-Feng; Hao, Ding-Jun; Fan, Ting; Huang, Hui-Min; Yao, Huan; Niu, Xiao-Feng

2014-02-05

The quaternary benzo[c]phenanthridine alkaloid, chelerythrine (CHE), is of great practical and research interest because of its pronounced, widespread physiological effects, primarily antimicrobial and anti-inflammatory, arising from its ability to interact with proteins and DNA. Although CHE was originally shown to possess anti-inflammatory properties, its effects on acute gastric ulcer have not been previously explored. The aim of the present study is to evaluate the protective effect of CHE on ethanol induced gastric ulcer in mice. Administration of CHE at doses of 1, 5 and 10mg/kg bodyweight prior to ethanol ingestion dose-dependently inhibited gastric ulcer. The gastric mucosal lesion was assessed by ulcer area, gastric juice acidity, myeloperoxidase (MPO) activities, macroscopic and histopathological examinations. CHE significantly reduced the gastric ulcer index, myeloperoxidase activities, macroscopic and histological score in a dose-dependent manner. In addition, CHE also significantly inhibited nitric oxide (NO) concentration, pro-inflammatory interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) level in serum and gastric mucosal in the mice exposed to ethanol induced ulceration in a dose-dependent manner. In addition, immunohistochemical analysis revealed that CHE markedly attenuated the overexpression of nuclear factor-κB in gastric mucosa of mice. It was concluded that CHE represents a potential therapeutic option to reduce the risk of gastric ulceration. In addition, acute toxicity study revealed no abnormal sign to the mice treated with CHE (15mg/kg). These findings suggest that the gastroprotective activity of CHE might contribute in adjusting the inflammatory cytokine by regulating the NF-κB signalling pathway. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Influence of serotonin and melatonin on some parameters of gastrointestinal activity.

PubMed

Bubenik, G A; Dhanvantari, S

1989-01-01

In vitro melatonin (M) reduced the tone of gut muscles and counteracted the tonic effect of serotonin (5-HT). In vivo 0.1 to 4 mg of 5-HT (contained in beeswax implants) decreased the food transit time (FTT) in a dose-dependent manner, but higher doses (5 and 6 mg) increased the FTT. Melatonin injected intraperitoneally into mice bearing 5-HT implants (2 mg per animal) blocked partly the serotonin effect and increased FTT by 50%; however, no dose-dependent effect was observed when doses between 0.01 and 1 mg were used. Surprisingly, M injected into intact mice decreased FTT to levels comparable to those observed in 5-HT implanted, M-treated mice. Again, this significant decrease was not dose-dependent between 0.02 and 1 mg. Although in vitro the maximal inhibition of serotonin-induced spasm was achieved when the M:5-HT ratio was 50-100:1, in vivo the effective ratio was about 1:1. This may indicate that part of M action on the gut movement is mediated by extraintestinal mechanisms. A hypothetical, counterbalancing system of M and 5-HT regulation of gut activity (similar to adrenaline-acetylcholine system) is proposed.

Dose and dose rate effects of whole-body gamma-irradiation: I. Lymphocytes and lymphoid organs

NASA Technical Reports Server (NTRS)

Pecaut, M. J.; Nelson, G. A.; Gridley, D. S.

2001-01-01

The major goal of part I of this study was to compare varying doses and dose rates of whole-body gamma-radiation on lymphoid cells and organs. C57BL/6 mice (n = 75) were exposed to 0, 0.5, 1.5, and 3.0 Gy gamma-rays (60Co) at 1 cGy/min (low-dose rate, LDR) and 80 cGy/min (high-dose rate, HDR) and euthanized 4 days later. A significant dose-dependent loss of spleen mass was observed with both LDR and HDR irradiation; for the thymus this was true only with HDR. Decreasing leukocyte and lymphocyte numbers occurred with increasing dose in blood and spleen at both dose rates. The numbers (not percentages) of CD3+ T lymphocytes decreased in the blood in a dose-dependent manner at both HDR and LDR. Splenic T cell counts decreased with dose only in HDR groups; percentages increased with dose at both dose rates. Dose-dependent decreases occurred in CD4+ T helper and CD8+ T cytotoxic cell counts at HDR and LDR. In the blood the percentages of CD4+ cells increased with increasing dose at both dose rates, whereas in the spleen the counts decreased only in the HDR groups. The percentages of the CD8+ population remained stable in both blood and spleen. CD19+ B cell counts and percentages in both compartments declined markedly with increasing HDR and LDR radiation. NK1.1+ natural killer cell numbers and proportions remained relatively stable. Overall, these data indicate that the observed changes were highly dependent on the dose, but not dose rate, and that cells in the spleen are more affected by dose rate than those in blood. The results also suggest that the response of lymphocytes in different body compartments may be variable.

Dose-dependent effects of hydrocortisone infusion on autobiographical memory recall

PubMed Central

Young, Kymberly; Drevets, Wayne C.; Schulkin, Jay; Erickson, Kristine

2011-01-01

The glucocorticoid hormone cortisol has been shown to impair episodic memory performance. The present study examined the effect of two doses of hydrocortisone (synthetic cortisol) administration on autobiographical memory retrieval. Healthy volunteers (n=66) were studied on two separate visits, during which they received placebo and either moderate-dose (0.15 mg/kg IV; n=33) or high-dose (0.45 mg/kg IV; n=33) hydrocortisone infusion. From 75 to 150 min post-infusion subjects performed an Autobiographical Memory Test and the California Verbal Learning Test (CVLT). The high-dose hydrocortisone administration reduced the percent of specific memories recalled (p = 0.04), increased the percent of categorical (nonspecific) memories recalled, and slowed response times for categorical memories (p <0.001), compared to placebo performance (p < 0.001). Under moderate-dose hydrocortisone the autobiographical memory performance did not change significantly with respect to percent of specific or categorical memories recalled or reaction times. Performance on the CVLT was not affected by hydrocortisone. These findings suggest that cortisol affects accessibility of autobiographical memories in a dose-dependent manner. Specifically, administration of hydrocortisone at doses analogous to those achieved under severe psychosocial stress impaired the specificity and speed of retrieval of autobiographical memories. PMID:21942435

Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-{alpha}

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

Tsukasaki, Masayuki; Yamada, Atsushi, E-mail: yamadaa@dent.showa-u.ac.jp; Suzuki, Dai

2011-07-15

Highlights: {yields} TNF-{alpha} inhibits POEM gene expression. {yields} Inhibition of POEM gene expression is caused by NF-{kappa}B activation by TNF-{alpha}. {yields} Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-{alpha}. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-{alpha} (TNF-{alpha}), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-{alpha}-induced down-regulation of POEM gene expression occurred in both time- andmore » dose-dependent manners through the nuclear factor kappa B (NF-{kappa}B) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-{alpha} in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-{alpha}-induced inhibition of osteoblast differentiation. These results suggest that TNF-{alpha} inhibits POEM expression through the NF-{kappa}B signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-{alpha}.« less

Original Research: Potential ocular protection and dynamic observation of Polygonatum sibiricum polysaccharide against streptozocin-induced diabetic rats' model.

PubMed

Wang, Yi; Qin, Shucun; Pen, Guoqing; Chen, Di; Han, Chao; Miao, Chunrun; Lu, Baojin; Su, Chao; Feng, Shanlong; Li, Wen; Han, Jingjing; Cho, Nam C; Si, Yanhong

2017-01-01

Ocular complications associated with diabetes mellitus are progressive and becoming one of the most important causes of morbidity worldwide. The purpose of the study is to evaluate the protective effect of Polygonatum sibiricum polysaccharide, an important component of Polygonatum sibiricum, on ocular complications in streptozotocin-induced diabetes mellitus rats. Sprague Dawley rats were made diabetic with streptozotocin(60 mg/kg, i.v.) and then the rats were treated with Polygonatum sibiricum polysaccharide 200, 400 and 800 mg/kg.d by gavage for 12 weeks. Biochemical analysis indicated that Polygonatum sibiricum polysaccharide lowered the levels of fasting blood glucose and glycated hemoglobin in blood and elevated the levels of insulin and C-peptide in plasma of diabetes mellitus rats in a dose-dependent manner. Physical measurements revealed that Polygonatum sibiricum polysaccharide improved clinical symptoms of polydipsia, polyphagia, polyuria and weight loss in diabetes mellitus rats. The content of malondialdehyde and activity of superoxide dismutase in plasma were determined, and the data showed Polygonatum sibiricum polysaccharide suppressed oxidative stress reaction. Lens opacification was observed using slit lamp illumination, and the data showed Polygonatum sibiricum polysaccharide delayed cataract progression in a dose-dependent manner. Electroretinogram showed Polygonatum sibiricum polysaccharide treatment reversed the decrease of electroretinogram b and OPs2 waves' amplitudes. Flash-visual evoked potential test indicated that the peak time of P2 wave was prolonged, and the amplitude of N2-P2 was lowered in diabetes mellitus group, and Polygonatum sibiricum polysaccharide suppressed these changes. Fundus fluorescein angiography showed Polygonatum sibiricum polysaccharide alleviated the retinal vasculopathy in a dose-dependent manner. In conclusion, these results suggest that the administration of Polygonatum sibiricum polysaccharide slows the progression of diabetic retinopathy and cataract through alleviating hyperglycemia and reducing oxidative stress in streptozotocin-induced diabetes mellitus rats. © 2016 by the Society for Experimental Biology and Medicine.

Production of reactive oxygen species by withaferin A causes loss of type collagen expression and COX-2 expression through the PI3K/Akt, p38, and JNK pathways in rabbit articular chondrocytes.

PubMed

Yu, Seon-Mi; Kim, Song-Ja

2013-11-01

Withaferin A (WFA) is a major chemical constituent of Withania somnifera, also known as Indian ginseng. Many recent reports have provided evidence of its anti-tumor, anti-inflammation, anti-oxidant, and immune modulatory activities. Although the compound appears to have a large number of effects, its defined mechanisms of action have not yet been determined. We investigated the effects of WFA on loss of type collagen expression and inflammation in rabbit articular chondrocytes. WFA increased the production of reactive oxygen species, suggesting the induction of oxidative stress, in a dose-dependent manner. Also, we confirmed that WFA causes loss of type collagen expression and inflammation as determined by a decrease of type II collagen expression and an increase of cyclooxygenase-2 (COX-2) expression via western blot analysis in a dose- and time- dependent manner. WFA also reduced the synthesis of sulfated proteoglycan via Alcian blue staining and caused the synthesis of prostaglandin E2 (PGE2) via assay kit in dose- and time-dependent manners. Treatment with N-acetyl-L-cysteine (NAC), an antioxidant, inhibited WFA-induced loss of type II collagen expression and increase in COX-2 expression, accompanied by inhibition of reactive oxygen species production. WFA increased phosphorylation of both Akt and p38. Inhibition of PI3K/Akt, p38, and JNK with LY294002 (LY), SB203580 (SB), or SP600125 (SP) in WFA-treated cells rescued the expression of type II collagen and suppressed the expression of COX-2. These results demonstrate that WFA induces loss of type collagen expression and inflammation via PI3K/Akt, p38, and JNK by generating reactive oxygen species in rabbit articular chondrocytes. © 2013 Published by Elsevier Inc.

Original Research: Potential ocular protection and dynamic observation of Polygonatum sibiricum polysaccharide against streptozocin-induced diabetic rats’ model

PubMed Central

Wang, Yi; Qin, Shucun; Pen, Guoqing; Chen, Di; Han, Chao; Miao, Chunrun; Lu, Baojin; Su, Chao; Feng, Shanlong; Li, Wen; Han, Jingjing

2016-01-01

Ocular complications associated with diabetes mellitus are progressive and becoming one of the most important causes of morbidity worldwide. The purpose of the study is to evaluate the protective effect of Polygonatum sibiricum polysaccharide, an important component of Polygonatum sibiricum, on ocular complications in streptozotocin-induced diabetes mellitus rats. Sprague Dawley rats were made diabetic with streptozotocin(60 mg/kg, i.v.) and then the rats were treated with Polygonatum sibiricum polysaccharide 200, 400 and 800 mg/kg.d by gavage for 12 weeks. Biochemical analysis indicated that Polygonatum sibiricum polysaccharide lowered the levels of fasting blood glucose and glycated hemoglobin in blood and elevated the levels of insulin and C-peptide in plasma of diabetes mellitus rats in a dose-dependent manner. Physical measurements revealed that Polygonatum sibiricum polysaccharide improved clinical symptoms of polydipsia, polyphagia, polyuria and weight loss in diabetes mellitus rats. The content of malondialdehyde and activity of superoxide dismutase in plasma were determined, and the data showed Polygonatum sibiricum polysaccharide suppressed oxidative stress reaction. Lens opacification was observed using slit lamp illumination, and the data showed Polygonatum sibiricum polysaccharide delayed cataract progression in a dose-dependent manner. Electroretinogram showed Polygonatum sibiricum polysaccharide treatment reversed the decrease of electroretinogram b and OPs2 waves’ amplitudes. Flash-visual evoked potential test indicated that the peak time of P2 wave was prolonged, and the amplitude of N2-P2 was lowered in diabetes mellitus group, and Polygonatum sibiricum polysaccharide suppressed these changes. Fundus fluorescein angiography showed Polygonatum sibiricum polysaccharide alleviated the retinal vasculopathy in a dose-dependent manner. In conclusion, these results suggest that the administration of Polygonatum sibiricum polysaccharide slows the progression of diabetic retinopathy and cataract through alleviating hyperglycemia and reducing oxidative stress in streptozotocin-induced diabetes mellitus rats. PMID:27510582

Cow's milk increases the activities of human nuclear receptors peroxisome proliferator-activated receptors alpha and delta and retinoid X receptor alpha involved in the regulation of energy homeostasis, obesity, and inflammation.

PubMed

Suhara, W; Koide, H; Okuzawa, T; Hayashi, D; Hashimoto, T; Kojo, H

2009-09-01

The nuclear peroxisome proliferator-activated receptors (PPAR) have been shown to play crucial roles in regulating energy homeostasis including lipid and carbohydrate metabolism, inflammatory responses, and cell proliferation, differentiation, and survival. Because PPAR agonists have the potential to prevent or ameliorate diseases such as hyperlipidemia, diabetes, atherosclerosis, and obesity, we have explored new natural agonists for PPAR. For this purpose, cow's milk was tested for agonistic activity toward human PPAR subtypes using a reporter gene assay. Milk increased human PPARalpha activity in a dose-dependent manner with a 3.2-fold increase at 0.5% (vol/vol). It also enhanced human PPARdelta activity in a dose-dependent manner with an 11.5-fold increase at 0.5%. However, it only slightly affected human PPARgamma activity. Ice cream, butter, and yogurt also increased the activities of PPARalpha and PPARdelta, whereas vegetable cream affected activity of PPARdelta but not PPARalpha. Skim milk enhanced the activity of PPAR to a lesser degree than regular milk. Milk and fresh cream increased the activity of human retinoid X receptor (RXR)alpha as well as PPARalpha and PPARdelta, whereas neither affected vitamin D3 receptor, estrogen receptors alpha and beta, or thyroid receptors alpha and beta. Both milk and fresh cream were shown by quantitative real-time PCR to increase the quantity of mRNA for uncoupling protein 2 (UCP2), an energy expenditure gene, in a dose-dependent manner. The increase in UCP2 mRNA was found to be reduced by treatment with PPARdelta-short interfering (si)RNA. This study unambiguously clarified at the cellular level that cow's milk increased the activities of human PPARalpha, PPARdelta, and RXRalpha. The possible role in enhancing the activities of PPARalpha, PPARdelta, and RXRalpha, and the health benefits of cow's milk were discussed.

Adenosine A2A receptor agonist prevents cardiac remodeling and dysfunction in spontaneously hypertensive male rats after myocardial infarction

PubMed Central

da Silva, Jaqueline S; Gabriel-Costa, Daniele; Sudo, Roberto T; Wang, Hao; Groban, Leanne; Ferraz, Emanuele B; Nascimento, José Hamilton M; Fraga, Carlos Alberto M; Barreiro, Eliezer J; Zapata-Sudo, Gisele

2017-01-01

Background This work evaluated the hypothesis that 3,4-methylenedioxybenzoyl-2-thienylhydrazone (LASSBio-294), an agonist of adenosine A2A receptor, could be beneficial for preventing cardiac dysfunction due to hypertension associated with myocardial infarction (MI). Methods Male spontaneously hypertensive rats (SHR) were randomly divided into four groups (six animals per group): sham-operation (SHR-Sham), and myocardial infarction rats (SHR-MI) were treated orally either with vehicle or LASSBio-294 (10 and 20 mg.kg−1.d−1) for 4 weeks. Echocardiography and in vivo hemodynamic parameters measured left ventricle (LV) structure and function. Exercise tolerance was evaluated using a treadmill test. Cardiac remodeling was accessed by LV collagen deposition and tumor necrosis factor α expression. Results Early mitral inflow velocity was significantly reduced in the SHR-MI group, and there was significant recovery in a dose-dependent manner after treatment with LASSBio-294. Exercise intolerance observed in the SHR-MI group was prevented by 10 mg.kg−1.d−1 of LASS-Bio-294, and exercise tolerance exceeded that of the SHR-Sham group at 20 mg.kg−1.d−1. LV end-diastolic pressure increased after MI, and this was prevented by 10 and 20 mg.kg−1.d−1 of LASSBio-294. Sarcoplasmic reticulum Ca2+ ATPase levels were restored in a dose-dependent manner after treatment with LASSBio-294. Fibrosis and inflammatory processes were also counteracted by LASSBio-294, with reductions in LV collagen deposition and tumor necrosis factor α expression. Conclusion In summary, oral administration of LASSBio-294 after MI in a dose-dependent manner prevented the development of cardiac dysfunction, demonstrating this compound’s potential as an alternative treatment for heart failure in the setting of ischemic heart disease with superimposed chronic hypertension. PMID:28293100

Erythrocyte Omega-3 Fatty Acid Content in Elite Athletes in Response to Omega-3 Supplementation: A Dose-Response Pilot Study

PubMed Central

Rueda, Félix; Pons, Victoria; Banquells, Montserrat; Cordobilla, Begoña; Domingo, Joan Carles

2017-01-01

Introduction Supplementation of Omega-3 fatty acids (n-3FA) in athletes is related to the anti-inflammatory and/or antioxidant effect and consequently its action on all the processes of tissue restoration and adaptation to physical stress. Objective Evaluate the Omega-3 Index (O3Ix) response, in red blood cells, to supplemental EPA + DHA intake in the form of high purity and stable composition gums (G), in elite summer athletes. Method Twenty-four summer sport athletes of both sexes, pertaining to the Olympic Training Center in Spain, were randomized to two groups (2G = 760 or 3G = 1140 mg of n-3 FA in Omegafort OKids, Ferrer Intl.) for 4 months. Five athletes and four training staff volunteers were control group. Results The O3Ix was lower than 8% in 93.1% of all the athletes. The supplementation worked in a dose-dependent manner: 144% for the 3G dose and 135% for the 2G, both p < 0.001, with a 3% significant decrease of Omega-6 FAs. No changes were observed for the control group. Conclusions Supplementation with n-3FA increases the content of EPA DHA in the red blood cells at 4 months in a dose-dependent manner. Athletes with lower basal O3Ix were more prone to increment their levels. The study is registered with Protocol Registration and Results System (ClinicalTrials.gov) number NCT02610270. PMID:28656110

Antioxidant, analgesic and anti-inflammatory activities of the methanolic extract of Piper betle leaves.

PubMed

Alam, Badrul; Akter, Fahima; Parvin, Nahida; Sharmin Pia, Rashna; Akter, Sharmin; Chowdhury, Jesmin; Sifath-E-Jahan, Kazi; Haque, Ekramul

2013-01-01

The present study was designed to evaluate the antioxidant, analgesic, and anti-inflammatory activities of the methanolic extract of Piper betle leaves (MPBL). MPBL was evaluated for anti-inflammatory activity using carrageenan-induced hind paw edema model. Analgesic activity of MPBL was evaluated by hot plate, writhing, and formalin tests. Total phenolic and flavonoids content, total antioxidant activity, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, peroxynitrate (ONOO) as well as inhibition of total ROS generation, and assessment of reducing power were used to evaluate antioxidant potential of MPBL. The extract of MPBL, at the dose of 100 and 200 mg/kg, produced a significant (p<0.05) increase in pain threshold in hot plate method whereas significantly (p<0.05) reduced the writhing caused by acetic acid and the number of licks induced by formalin in a dose-dependent manner. The same ranges of doses of MPBL caused significant (p<0.05) inhibition of carrageenan-induced paw edema after 4 h in a dose-dependent manner. In DPPH, ONOO(-), and total ROS scavenging method, MPBL showed good antioxidant potentiality with the IC50 value of 16.33±1.02, 25.16±0.61 , and 41.72±0.48 µg/ml, respectively with a significant (p<0.05) good reducing power. The findings of the study suggested that MPBL has strong analgesic, anti-inflammatory, and antioxidant effects, conforming the traditional use of this plant for inflammatory pain alleviation to its antioxidant potentiality.

Pharmacological Evaluation of Naproxen Metal Complexes on Antinociceptive, Anxiolytic, CNS Depressant, and Hypoglycemic Properties

PubMed Central

Das, Narhari; Abdur Rahman, S. M.

2016-01-01

Purpose. The present study was designed to investigate the antinociceptive, anxiolytic, CNS depressant, and hypoglycemic effects of the naproxen metal complexes. Methods. The antinociceptive activity was evaluated by acetic acid-induced writhing method and radiant heat tail-flick method while anxiolytic activity was evaluated by elevated plus maze model. The CNS depressant activity of naproxen metal complexes was assessed using phenobarbitone-induced sleeping time test and the hypoglycemic test was performed using oral glucose tolerance test. Results. Metal complexes significantly (P < 0.001) reduced the number of abdominal muscle contractions induced by 0.7% acetic acid solution in a dose dependent manner. At the dose of 25 mg/kg body weight p.o. copper, cobalt, and zinc complexes exhibited higher antinociceptive activity having 59.15%, 60.56%, and 57.75% of writhing inhibition, respectively, than the parent ligand naproxen (54.93%). In tail-flick test, at both doses of 25 and 50 mg/kg, the copper, cobalt, silver, and zinc complexes showed higher antinociceptive activity after 90 minutes than the parent drug naproxen. In elevated plus maze (EPM) model the cobalt and zinc complexes of naproxen showed significant anxiolytic effects in dose dependent manner, while the copper, cobalt, and zinc complexes showed significant CNS depressant and hypoglycemic activity. Conclusion. The present study demonstrated that copper, cobalt, and zinc complexes possess higher antinociceptive, anxiolytic, CNS depressant, and hypoglycemic properties than the parent ligand. PMID:27478435

Cardioprotective effects of gallic acid in diabetes-induced myocardial dysfunction in rats

PubMed Central

Patel, Snehal S.; Goyal, Ramesh K.

2011-01-01

Background: Normalization of hyperglycemia, hyperlipidemia, and oxidative stress is an important objective in preventing diabetes-induced cardiac dysfunction. Objective: This study was undertaken to examine the effects of gallic acid in myocardial dysfunctions associated with type-1 diabetes. Materials and Methods: Diabetes was induced by single intravenous injection of streptozotocin (STZ, 50 mg/kg i.v.). Gallic acid was administered daily at three different doses (100, 50, and 25 mg/kg p.o.) for 8 weeks at the end of which blood samples were collected and analyzed for various biochemical parameters. Results: Injection of STZ produced significant loss of body weight (BW), polyphagia, polydypsia, hyperglycemia, hypoinsulinemia, hyperlipidemia, hypertension, bradycardia, and myocardial functional alterations. Treatment with gallic acid significantly lowered fasting glucose, the AUCglucose level in a dose-dependent manner; however, the insulin level was not increased significantly at same the dose and prevented loss of BW, polyphagia, and polydypsia in diabetic rats. It also prevented STZ-induced hyperlipidemia, hypertension, bradycardia, structural alterations in cardiac tissue such as increase in force of contraction, left ventricular weight to body weight ratio, collagen content, protein content, serum lactate dehydrogenase, and creatinine kinase levels in a dose-dependent manner. Further, treatment also produced reduction in lipid peroxidation and increase in antioxidant parameters in heart of diabetic rats. Conclusion: The results of this study suggest that gallic acid to be beneficial for the treatment of myocardial damage associated with type-1 diabetes. PMID:22224046

Association of brominated proteins and changes in protein expression in the rat kidney with subcarcinogenic to carcinogenic doses of bromate

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

Kolisetty, Narendrababu; Bull, Richard J.; Muralidhara, Srinivasa

2013-10-15

The water disinfection byproduct bromate (BrO{sub 3}{sup −}) produces cytotoxic and carcinogenic effects in rat kidneys. Our previous studies demonstrated that BrO{sub 3}{sup −} caused sex-dependent differences in renal gene and protein expression in rats and the elimination of brominated organic carbon in their urine. The present study examined changes in renal cell apoptosis and protein expression in male and female F344 rats treated with BrO{sub 3}{sup −} and associated these changes with accumulation of 3-bromotyrosine (3-BT)-modified proteins. Rats were treated with 0, 11.5, 46 and 308 mg/L BrO{sub 3}{sup −} in drinking water for 28 days and renal sectionsmore » were prepared and examined for apoptosis (TUNEL-staining), 8-oxo-deoxyguanosine (8-oxoG), 3-BT, osteopontin, Kim-1, clusterin, and p-21 expression. TUNEL-staining in renal proximal tubules increased in a dose-related manner beginning at 11.5 mg BrO{sub 3}{sup −}/L in female rats and 46 mg/L in males. Increased 8-oxoG staining was observed at doses as low as 46 mg/L. Osteopontin expression also increased in a dose-related manner after treatment with 46 mg/L, in males only. In contrast, Kim-1 expression increased in a dose-related manner in both sexes, although to a greater extent in females at the highest dose. Clusterin and p21 expression also increased in a dose-related manner in both sexes. The expression of 3-BT-modified proteins only increased in male rats, following a pattern previously reported for accumulation of α-2{sub u}-globulin. Increases in apoptosis in renal proximal tubules of male and female rats at the lowest doses suggest a common mode of action for renal carcinogenesis for the two sexes that is independent of α-2{sub u}-globulin nephropathy. - Highlights: • Bromate induced nephrotoxicity in both male and female rats by similar mechanisms. • Apoptosis was seen in both male and female rats at the lowest doses tested. • Bromate-induced apoptosis correlated to 8-oxo-deoxyguanosine formation. • Bromate increased the level of 3-bromotyrosine-modified proteins in male rats only. • These data identify possible novel mechanisms for bromate-induced nephrotoxicity.« less

Dose-dependent biodistribution of prenatal exposure to rutile-type titanium dioxide nanoparticles on mouse testis

NASA Astrophysics Data System (ADS)

Kubo-Irie, Miyoko; Uchida, Hiroki; Mastuzawa, Shotaro; Yoshida, Yasuko; Shinkai, Yusuke; Suzuki, Kenichiro; Yokota, Satoshi; Oshio, Shigeru; Takeda, Ken

2014-02-01

Titanium dioxide nanoparticles (nano-TiO2), believed to be inert and safe, are used in many products especially rutile-type in cosmetics. Detection, localization, and count of nanoparticles in tissue sections are of considerable current interest. Here, we evaluate the dose-dependent biodistribution of rutile-type nano-TiO2 exposure during pregnancy on offspring testes. Pregnant mice were subcutaneously injected five times with 0.1 ml of sequentially diluted of nano-TiO2 powder, 35 nm with primary diameter, suspensions (1, 10, 100, or 1,000 μg/ml), and received total doses of 0.5, 5, 50, and 500 μg, respectively. Prior to injection, the size distribution of nano-TiO2 was analyzed by dynamic light scattering measurement. The average diameter was increased in a dose-dependent manner. The most diluted concentration, 1 μg/ml suspension, contained small agglomerates averaging 193.3 ± 5.4 nm in diameter. The offspring testes were examined at 12 weeks postpartum. Individual particle analysis in testicular sections under scanning and transmission electron microscopy enabled us to understand the biodistribution. The correlation between nano-TiO2 doses injected to pregnant mice, and the number of agglomerates in the offspring testes was demonstrated to be dose-dependent by semiquantitative evaluation. However, the agglomerate size was below 200 nm in the testicular sections of all recipient groups, independent from the injected dose during pregnancy.

Antibacterial activity of polyphenolic fraction of Kombucha against Vibrio cholerae: targeting cell membrane.

PubMed

Bhattacharya, D; Ghosh, D; Bhattacharya, S; Sarkar, S; Karmakar, P; Koley, H; Gachhui, R

2018-02-01

The present study was undertaken to determine the mechanism of antibacterial activity of a polyphenolic fraction, composed of mainly catechin and isorhamnetin, previously isolated from Kombucha, a 14-day fermented beverage of sugared black tea, against the enteropathogen Vibrio cholerae N16961. Bacterial growth was found to be seriously impaired by the polyphenolic fraction in a dose-dependent manner. Scanning Electron Microscopy demonstrated morphological alterations in bacterial cells when exposed to the polyphenolic fraction in a concentration-dependent manner. Permeabilization assays confirmed that the fraction disrupted bacterial membrane integrity in both time- and dose-dependent manners, which were proportional to the production of intracellular reactive oxygen species (ROS). Furthermore, each of the polyphenols catechin and isorhamnetin showed the ability to permeate bacterial cell membranes by generating oxidative stress, thereby suggesting their role in the antibacterial potential of Kombucha. Thus, the basic mechanism of antibacterial activity of the Kombucha polyphenolic fraction against V. cholerae involved bacterial membrane permeabilization and morphological changes, which might be due to the generation of intracellular ROS. To the best of our knowledge, this is the first report on the investigation of antibacterial mechanism of Kombucha, which is mostly attributed to its polyphenolic content. The emergence of multidrug-resistant Vibrio cholerae strains has hindered an efficient anti-Vibrio therapy. This study has demonstrated the membrane damage-mediated antibacterial mechanism of Kombucha, a popular fermented beverage of sugared tea, which is mostly attributed to its polyphenolic content. This study also implies the exploitation of Kombucha as a potential new source of bioactive polyphenols against V. cholerae. © 2017 The Society for Applied Microbiology.

Pleiotropic effects of fenofibrate therapy on rats with hypertriglycemia.

PubMed

Sun, Bing; Xie, Yuan; Jiang, Jinfa; Wang, Yiping; Xu, Xiaolin; Zhao, Cuimei; Huang, Feifei

2015-04-14

Cardio-protective effect of fibrate therapy is controversial and current research is to evaluate the effect of fenofibrate therapy on rats with hypertriglycemia. Rats with hypertriglycemia were produced by 10% fructose administration (10 ml daily) for 4 weeks. After model has been successfully produced as reflected by increased triglyceride level, different doses of fenofibrate, namely low dose (50 mg/kg body weight) and high dose (100 mg/kg body weight), were orally prescribed for 2 weeks. At baseline, 4 weeks of fructose administration and 2 weeks of fenofibrate therapy, parameters of interest were evaluated and compared. At baseline, no significant differences of parameter were observed between groups. After 4 weeks of fructose prescription, triglyceride level increased in company with high density lipoprotein cholesterol (HDL-C) and apoprotein A1 (ApoA1) decreased. C-reactive protein (CRP) and malondialdehyde (MDA) levels were also elevated. Endothelial function was impaired as reflected by reduced nitric oxide (NO) production and elevated serum asymmetric dimethylarginine (ADMA) level. All these changes were significant as compared to the control group (P<0.05), suggesting that short-term of triglyceride elevation could potently initiate atherosclerosis. With 2 weeks of fenofibrate therapy, in comparison to un-treated group, triglyceride level was significantly reduced in parallel with HDL-C and ApoA1 elevation. Inflammation and oxidation were also profoundly ameliorated as reflected by CRP and MDA reduction. Notably, NO production was enhanced in company with serum ADMA level decrease. Overall, these improvements manifested in a dose-dependent manner, which was supported by multivariate regression analysis showing that after adjusted to other variables, the dose of fenofibrate therapy remained significantly associated with NO production and serum ADMA level, with OR of 1.042 (high-dose versus low-dose, 95% CI 1.028-1.055, P<0.05). Fenofibrate therapy not only could reduce triglyceride level but also confer pleiotropic effects in terms of endothelium-protection and amelioration of inflammation and oxidation in a dose-dependent manner.

A Combination of Buprenorphine and Naltrexone Blocks Compulsive Cocaine Intake in Rodents Without Producing Dependence

PubMed Central

Wee, Sunmee; Vendruscolo, Leandro F.; Misra, Kaushik K.; Schlosburg, Joel E.; Koob, George F.

2012-01-01

Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non–opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist–induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction. PMID:22875830

A combination of buprenorphine and naltrexone blocks compulsive cocaine intake in rodents without producing dependence.

PubMed

Wee, Sunmee; Vendruscolo, Leandro F; Misra, Kaushik K; Schlosburg, Joel E; Koob, George F

2012-08-08

Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non-opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist-induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction.

Emulsification Increases the Acute Ketogenic Effect and Bioavailability of Medium-Chain Triglycerides in Humans

PubMed Central

Courchesne-Loyer, Alexandre; Lowry, Carolyn-Mary; St-Pierre, Valérie; Vandenberghe, Camille; Fortier, Mélanie; Castellano, Christian-Alexandre; Wagner, J Richard; Cunnane, Stephen C

2017-01-01

Abstract Background: Lower-brain glucose uptake is commonly present before the onset of cognitive deterioration associated with aging and may increase the risk of Alzheimer disease. Ketones are the brain's main alternative energy substrate to glucose. Medium-chain triglycerides (MCTs) are rapidly β-oxidized and are ketogenic but also have gastrointestinal side effects. We assessed whether MCT emulsification into a lactose-free skim-milk matrix [emulsified MCTs (MCT-Es)] would improve ketogenesis, reduce side effects, or both compared with the same oral dose of MCTs consumed without emulsification [nonemulsified MCTs (MCT-NEs)]. Objectives: Our aims were to show that, in healthy adults, MCT-Es will induce higher ketonemia and have fewer side effects than MCT-NEs and the effects of MCT-NEs and MCT-Es on ketogenesis and plasma medium-chain fatty acids (MCFAs) will be dose-dependent. Methods: Using a metabolic study day protocol, 10 healthy adults were each given 3 separate doses (10, 20, or 30 g) of MCT-NEs or MCT-Es with a standard breakfast or no treatment [control (CTL)]. Blood samples were taken every 30 min for 4 h to measure plasma ketones (β-hydroxybutyrate and acetoacetate), octanoate, decanoate, and other metabolites. Participants completed a side-effects questionnaire at the end of each study day. Results: Compared with CTL, MCT-NEs increased ketogenesis by 2-fold with no significant differences between doses. MCT-Es increased total plasma ketones by 2- to 4-fold in a dose-dependent manner. Compared with MCT-NEs, MCT-Es increased plasma MCFA bioavailability (F) by 2- to 3-fold and decreased the number of side effects by ∼50%. Conclusions: Emulsification increased the ketogenic effect and decreased side effects in a dose-dependent manner for single doses of MCTs ≤30 g under matching conditions. Further investigation is needed to establish whether emulsification could sustain ketogenesis and minimize side effects and therefore be used as a treatment to change brain ketone availability over a prolonged period of time. This trial was registered at clinicaltrials.gov as NCT02409927.

Haloperidol Disrupts Opioid-Antinociceptive Tolerance and Physical Dependence

PubMed Central

Yang, Cheng; Chen, Yan; Tang, Lei

2011-01-01

Previous studies from our laboratory and others have implicated a critical role of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in opioid tolerance and dependence. Translational research targeting the CaMKII pathway is challenging, if not impossible, because of a lack of selective inhibitors. We discovered in a preliminary study that haloperidol, a butyrophenone antipsychotic drug, inhibited CaMKII, which led us to hypothesize that haloperidol can attenuate opioid tolerance and dependence by inhibiting CaMKII. The hypothesis was tested in two rodent models of opioid tolerance and dependence. Pretreatment with haloperidol (0.2–1.0 mg/kg i.p.) prevented the development of morphine tolerance and dependence in a dose-dependent manner. Short-term treatment with haloperidol (0.06–0.60 mg/kg i.p.) dose-dependently reversed the established morphine-antinociceptive tolerance and physical dependence. Correlating with behavioral effects, pretreatment or short-term treatment with haloperidol dose-dependently inhibited morphine-induced up-regulation of supraspinal and spinal CaMKIIα activity. Moreover, haloperidol given orally was also effective in attenuating morphine-induced CaMKIIα activity, antinociceptive tolerance, and physical dependence. Taken together, these data suggest that haloperidol attenuates opioid tolerance and dependence by suppressing CaMKII activity. Because haloperidol is a clinically used drug that can be taken orally, we propose that the drug may be of use in attenuating opioid tolerance and dependence. PMID:21436292

Lack of effect of ezogabine/retigabine on the pharmacokinetics of digoxin in healthy individuals: results from a drug–drug interaction study

PubMed Central

Tompson, Debra J; Crean, Christopher S; Buraglio, Mauro; Arumugham, Thangam

2014-01-01

Introduction The potential for ezogabine/retigabine (EZG/RTG) and its N-acetyl metabolite (NAMR) to inhibit the transporter protein P-glycoprotein-(P-gp)-mediated digoxin transport was tested in vitro. EZG/RTG did not inhibit P-gp. However, NAMR inhibited P-gp in a concentration-dependent manner. Based on these in vitro results, NAMR had the potential to inhibit P-gp at therapeutic doses of EZG/RTG (600–1,200 mg/day). As digoxin has a narrow therapeutic index, inhibition of digoxin clearance may have an impact on its safety. Methods An open-label, single-center, two session, fixed-sequence study was conducted to assess the effect of co-administration of therapeutic doses of EZG/RTG on digoxin pharmacokinetics in healthy adults. In session 1, subjects received a single dose of digoxin 0.25 mg. In session 2, EZG/RTG was up-titrated over 6 weeks. Digoxin 0.25 mg was co-administered at EZG/RTG steady-state doses of 600, 900, and, based on tolerability, 1,050/1,200 mg/day. Blood samples were collected over 144 hours for determination of digoxin, EZG/RTG, and NAMR concentrations. Urine samples were collected over 48 hours for determination of digoxin concentrations. Results Of 30 subjects enrolled, 29 were included in the pharmacokinetic analysis. Compared with digoxin alone, co-administration with EZG/RTG led to small increases in the digoxin plasma area under the concentration–time curve (AUC)0–120 at doses of 600, 900, and 1,050/1,200 mg (geometric mean ratio 1.08, 90% confidence interval [CI] 1.01–1.15; 1.18, 90% CI 1.10–1.27; 1.13, 90% CI 1.05–1.21, respectively). Safety was consistent with previous repeat-dose studies of EZG/RTG in healthy subjects. Conclusion Co-administration of EZG/RTG across the therapeutic range resulted in small, non-dose-dependent and non-clinically relevant increases in digoxin systemic exposure, suggesting that digoxin dose adjustment is not necessary. PMID:25342921

DHA down-regulates phenobarbital-induced cytochrome P450 2B1 gene expression in rat primary hepatocytes by attenuating CAR translocation

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

Li, C.-C.; Lii, C.-K.; Liu, K.-L.

The constitutive androstane receptor (CAR) plays an important role in regulating the expression of detoxifying enzymes, including cytochrome P450 2B (CYP 2B). Phenobarbital (PB) induction of human CYP 2B6 and mouse CYP 2b10 has been shown to be mediated by CAR. Our previous study showed that PB-induced CYP 2B1 expression in rat primary hepatocytes is down-regulated by both n-6 and n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA); however, the mechanism for this down-regulation by DHA was previously unknown. The objective of the present study was to determine whether change in CAR translocation is involved in the down-regulation bymore » n-6 and n-3 PUFAs of PB-induced CYP 2B1 expression in rat primary hepatocytes. We used 100 {mu}M arachidonic acid, linoleic acid, eicosapentaenoic acid, and DHA to test this hypothesis. PB triggered the translocation of CAR from the cytosol into the nucleus in a dose-dependent and time-dependent manner in our hepatocyte system, and the CAR distribution in rat primary hepatocytes was significantly affected by DHA. DHA treatment decreased PB-inducible accumulation of CAR in the nuclear fraction and increased it in the cytosolic fraction in a dose-dependent manner. The down-regulation of CYP 2B1 expression by DHA occurred in a dose-dependent manner, and a similar pattern was found for the nuclear accumulation of CAR. The results of immunoprecipitation showed a CAR/RXR heterodimer bound to nuclear receptor binding site 1 (NR-1) of the PB-responsive enhancer module (PBREM) of the CYP 2B1gene. The EMSA results showed that PB-induced CAR binding to NR-1 was attenuated by DHA. Taken together, these results suggest that attenuation of CAR translocation and decreased subsequent binding to NR-1 are involved in DHA's down-regulation of PB-induced CYP 2B1 expression.« less

Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2

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

Ahmad, Javed; Ahamed, Maqusood, E-mail: maqusood@gmail.com; Akhtar, Mohd Javed

Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 μg/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion ofmore » glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level. -- Highlights: ► We explored the mechanisms of toxicity caused by silica NPs in human liver HepG2 cells. ► Silica NPs induced a dose-dependent cytotoxicity in HepG2 cells. ► Silica NPs induced ROS generation and oxidative stress in a dose-dependent manner. ► Silica NPs were also modulated apoptosis markers both at mRNA and protein levels. ► ROS mediated apoptosis induced by silica NPs was preserved by vitamin C.« less

Prostaglandins mediate the stimulatory effects of endothelin-1 on cAMP accumulation and inositol-1,4,5-trisphosphate production and contraction in cat iris sphincter.

PubMed

Yousufzai, S Y; Ye, Z; Abdel-Latif, A A

1995-12-01

We previously reported that in the iris sphincter smooth muscle, endothelin-1 (ET-1) activates both adenylyl cyclase and the phosphoinositide cascade and that the changes in the levels of cAMP and inositol-1,4,5-trisphosphate (IP3) produced are species specific. In the present study, we examined the mechanism of the ET-1 effects in cat iris sphincter. In general, we found that ET-1 (0.1 microM) increased prostaglandin E2 (PGE2) release by 156%, cAMP accumulation by 310%, IP3 production by 88% and induced contraction; that PGE2 increased cAMP accumulation, IP3 production and contraction; and that the effects of ET-1 are inhibited by indomethacin (Indo), suggesting that arachidonic acid metabolites may mediate the responses to the peptide. Kinetic studies revealed the following: (1) The effect of ET-1 on cAMP accumulation is rapid (within 30 sec), dose dependent (EC50 = 5.8 nM) and completely abolished by Indo (Ki = 0.16 microM), a cyclooxygenase inhibitor, but not by nordihydroguairetic acid, a lipoxygenase inhibitor, implying the involvement of PGs. (2) ET-1 dose-dependently evoked PGe2 release (EC50 = 1.8 nM), IP3 production (EC50 = 4.5 nM) and contraction (EC50 = 5 nM) and that all of these responses were inhibited by Indo. (3) PGE2 increased cAMP accumulation in a dose-dependent manner with an EC50 of 1.5 x 10(-7) M, and PGD2 and PGF2 alpha had little effect on the cyclic nucleotide. (4) PGE2 (1 microM), increased IP3 production by 55% and induced muscle contraction in a dose-dependent manner (EC50 = 40 nM). We conclude from these data that in cat iris sphincter PGs may mediate ET-1-induced cAMP accumulation, IP3 production and smooth muscle contraction.

Adaptogenic and nootropic activities of aqueous extract of Vitis vinifera (grape seed): an experimental study in rat model

PubMed Central

Sreemantula, Satyanarayana; Nammi, Srinivas; Kolanukonda, Rajabhanu; Koppula, Sushruta; Boini, Krishna M

2005-01-01

Background The aerial parts of Vitis vinifera (common grape or European grape) have been widely used in Ayurveda to treat a variety of common and stress related disorders. In the present investigation, the seed extract of V. vinifera was evaluated for antistress activity in normal and stress induced rats. Furthermore, the extract was studied for nootropic activity in rats and in-vitro antioxidant potential to correlate its antistress activity. Methods For the evaluation of antistress activity, groups of rats (n = 6) were subjected to forced swim stress one hour after daily treatment of V. vinifera extract. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as non-invasive biomarkers to assess the antistress activity. The 24 h urinary excretion of vanillylmandelic acid (VMA) and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The nootropic activity of the extract as determined from acquisition, retention and retrieval in rats was studied by conditioned avoidance response using Cook's pole climbing apparatus. The in vitro antioxidant activity was determined based on the ability of V. vinifera to scavenge hydroxyl radicals. Results Daily administration of V. vinifera at doses of 100, 200 and 300 mg/kg body weight one hour prior to induction of stress inhibited the stress induced urinary biochemical changes in a dose dependent manner. However, no change in the urinary excretion of VMA and ascorbic acid was observed in normal animals at all the doses studied. The cognition, as determined by the acquisition, retention and recovery in rats was observed to be dose dependent. The extract also produced significant inhibition of hydroxyl radicals in comparison to ascorbic acid in a dose dependent manner. Conclusion The present study provides scientific support for the antistress (adaptogenic), antioxidant and nootropic activities of V. vinifera seed extract and substantiate the traditional claims for the usage of grape fruits and seeds in stress induced disorders. PMID:15656916

Immediate effect of exercise on achilles tendon properties: systematic review.

PubMed

Obst, Steven J; Barrett, Rod S; Newsham-West, Richard

2013-08-01

Understanding the mechanical and morphological adaptation of the Achilles tendon (AT) in response to acute exercise could have important implications for athletic performance, injury prevention, and rehabilitation. The purpose of this study was to conduct a systematic review and critical evaluation of the literature to determine the immediate effect of a single bout of exercise on the mechanical and morphological properties of the AT in vivo. Five electronic research databases were systematically searched for intervention-based studies reporting mechanical and morphological properties of the AT after a single bout of exercise. Searches revealed 3292 possible articles; 21 met the inclusion criteria. There is evidence that maximal isometric contractions and prolonged static stretching (>5 min) of the triceps surae complex cause an immediate decrease in AT stiffness, whereas prolonged running and hopping have minimal effect. Limited but consistent evidence exists, indicating that AT hysteresis is reduced after prolonged static stretching. Consistent evidence supports a reduction in free AT diameter (anterior-posterior) after dynamic ankle exercise, and this change appears most pronounced in the healthy tendon and after eccentric exercise. The mechanical and morphological properties of the AT in vivo are affected by acute exercise in a mode- and dose-dependent manner. Transient changes in AT stiffness, hysteresis, and diameter after unaccustomed exercise modes and doses may expose the tendon to increased risk of strain injury and impact on the mechanical function of the triceps surae muscle-tendon unit.

Bowel cleansing before colonoscopy: Balancing efficacy, safety, cost and patient tolerance

PubMed Central

Harrison, Nicole M; Hjelkrem, Michael C

2016-01-01

Effective colorectal cancer screening relies on reliable colonoscopy findings which are themselves dependent on adequate bowel cleansing. Research has consistently demonstrated that inadequate bowel preparation adversely affects the adenoma detection rate and leads gastroenterologists to recommend earlier follow up than is consistent with published guidelines. Poor preparation affects as many as 30% of colonoscopies and contributes to an increased cost of colonoscopies. Patient tolerability is strongly affected by the preparation chosen and manner in which it is administered. Poor tolerability is, in turn, associated with lower quality bowel preparations. Recently, several new developments in both agents being used for bowel preparation and in the timing of administration have brought endoscopists closer to achieving the goal of effective, reliable, safe, and tolerable regimens. Historically, large volume preparations given in a single dose were administered to patients in order to achieve adequate bowel cleansing. These were poorly tolerated, and the unpleasant taste of and significant side effects produced by these large volume regimens contributed significantly to patients’ inability to reliably complete the preparation and to a reluctance to repeat the procedure. Smaller volumes, including preparations that are administered as tablets to be consumed with water, given as split doses have significantly improved both the patient experience and efficacy, and an appreciation of the importance of the preparation to colonoscopy interval have produced additional cleansing. PMID:26788258

Fibrinogen Induces Biofilm Formation by Streptococcus suis and Enhances Its Antibiotic Resistance▿

PubMed Central

Bonifait, Laetitia; Grignon, Louis; Grenier, Daniel

2008-01-01

In this study, we showed that supplementing the culture medium with fibrinogen induced biofilm formation by Streptococcus suis in a dose-dependent manner. Biofilm-grown S. suis cells were much more resistant to penicillin G than planktonic cells. S. suis bound fibrinogen to its surface, a property that likely contributes to biofilm formation. PMID:18539785

Fibrinogen induces biofilm formation by Streptococcus suis and enhances its antibiotic resistance.

PubMed

Bonifait, Laetitia; Grignon, Louis; Grenier, Daniel

2008-08-01

In this study, we showed that supplementing the culture medium with fibrinogen induced biofilm formation by Streptococcus suis in a dose-dependent manner. Biofilm-grown S. suis cells were much more resistant to penicillin G than planktonic cells. S. suis bound fibrinogen to its surface, a property that likely contributes to biofilm formation.

In utero exposure to di(n)butyl phthalate reduces testicular testosterone and testis size in a dose-dependent manner in Harlan Sprague Dawley fetal rats

EPA Science Inventory

Phthalate esters are widely used to impart flexibility to plastics (e.g. plastic medical devices and children’s toys) as well as other uses in health and beauty products and some pharmaceuticals. Certain phthalate esters cause reproductive malformations and decrease androgen-dep...

Differences in DNA-damage in non-smoking men and women exposed to environmental tobacco smoke (ETS).

PubMed

Collier, Abby C; Dandge, Sachin D; Woodrow, James E; Pritsos, Chris A

2005-07-28

There is much data implicating environmental tobacco smoke (ETS) in the development and progression of disease, notably cancer, yet the mechanisms for this remain unclear. As ETS is both a pro-oxidant stressor and carcinogen, we investigated the relationship of ETS exposure to intracellular and serum levels of DNA-damage, both oxidative 8-hydroxy-2-deoxyguanosine (8OHdG) and general, in non-smokers from non-smoking households, occupationally exposed to ETS. General DNA-damage consisting of single and double strand breaks, alkali-labile sites and incomplete base-excision repair, increased significantly in a dose-dependent manner with ETS exposure in men (P=0.015, n=32, Pearson) but not women (P=0.736, n=17). Intracellular 8OHdG-DNA-damage and general DNA-damage were both greater in men than women (P=0.0005 and 0.016, respectively) but 8OHdG serum levels did not differ between the genders. Neither 8OHdG-DNA-damage nor serum levels correlated with increasing ETS exposure. This is the first study to demonstrate dose-dependent increases in DNA-damage from workplace ETS exposure. Perhaps most interesting was that despite equivalent ETS exposure, significantly greater DNA-damage occurred in men than women. These data may begin to provide a mechanistic rationale for the generally higher incidence of some diseases in males due to tobacco smoke and/or other genotoxic stressors.

Dual Effects of N,N-dimethylformamide on Cell Proliferation and Apoptosis in Breast Cancer

PubMed Central

Zhang, Jihong; Zhou, Daibing; Zhang, Lingyun; Lin, Qunbo; Ren, Weimin; Zhang, Jinguo; Nadeem, Lubna; Xu, Guoxiong

2017-01-01

N,N-dimethylformamide (DMF) has been widely used as an organic solvent in industries. DMF is a potential medication. However, the antitumorigenic role of DMF in breast cancer remains unclear. Here, we examined dose-dependent effects of DMF on proliferation and apoptosis in breast cancer MCF-7 and nontumorous MCF-12A cells. We found that DMF had a growth inhibitory effect in MCF-12A cells in a dose-dependent manner. By contrast, however, DMF had dual effects on cell proliferation and apoptosis in MCF-7 cells. DMF at a high dose (100 mM) significantly inhibited MCF-7 cell growth while at a low dose (1 mM) significantly stimulated MCF-7 cell growth (both P < .05). The inhibitory effect of DMF on cell proliferation was accompanied by the decrease of cyclin D1 and cyclin E1 protein expression, leading to the cell cycle arrest at the G0/G1 phase. Furthermore, a high-dose DMF significantly increased the number of early apoptotic cells by increasing cleaved caspase-9 and proapoptotic protein Bax expression and decreased the ratio of Bcl-xL/Bax (P < .01). Thus, our data demonstrated for the first time that DMF has dual effects on breast cancer cell behaviors depending upon its dose. Caution must be warranted in determining its effective dose for targeting breast cancer. PMID:29238273

A phase 1 study of the safety, tolerability, pharmacokinetics, and pharmacodynamics of TAK-063, a selective PDE10A inhibitor.

PubMed

Tsai, Max; Chrones, Lambros; Xie, Jinhui; Gevorkyan, Hakop; Macek, Thomas A

2016-10-01

Schizophrenia is a complex neuropsychiatric disorder characterized, in part, by impaired dopamine signaling. TAK-063 is a selective inhibitor of phosphodiesterase 10A, a key regulator of intracellular signaling pathways that is highly expressed in the striatum. Safety, tolerability, and pharmacokinetics of TAK-063 were evaluated in a phase 1 study. Healthy Japanese and non-Japanese volunteers were randomized into dose cohorts of 3, 10, 30, 100, 300, and 1000 mg. Each fasting volunteer randomly received a single dose of TAK-063 or placebo. Individuals from the 100-mg cohort also received a post-washout, 100-mg dose under fed conditions. A total of 84 volunteers enrolled (14 per cohort). The most common drug-related adverse events (AEs) were somnolence (33.3 %), orthostatic tachycardia (19.7 %), and orthostatic hypotension (9.1 %). The three severe AEs recorded occurred at the highest doses: orthostatic hypotension (n = 1; 300 mg) and somnolence (n = 2; 1000 mg). There were no deaths, serious AEs, or discontinuations due to AEs. TAK-063 exposure increased in a dose-dependent manner. Median T max was reached 3 to 4 h postdose. Fed conditions slowed absorption (T max =  6 h) and increased oral bioavailability. Renal elimination was negligible. Safety and pharmacokinetic parameters were similar between Japanese and non-Japanese subjects. Impairments in cognitive function consistent with the effects of other sedative or hypnotic agents were detected using a validated, computerized cognition battery, CNS Vital Signs. TAK-063 was safe and well tolerated at doses up to 1000 mg and demonstrated a pharmacokinetic profile supporting once-daily dosing. Further evaluation of the clinical safety and efficacy of TAK-063 is warranted.

SU-E-T-171: Missing Dose in Integrated EPID Images.

PubMed

King, B; Seymour, E; Nitschke, K

2012-06-01

A dosimetric artifact has been observed with Varian EPIDs in the presence of beam interrupts. This work determines the root cause and significance of this artifact. Integrated mode EPID images were acquired both with and without a manual beam interrupt for rectangular, sliding gap IMRT fields. Simultaneously, the individual frames were captured on a separate computer using a frame-grabber system. Synchronization of the individual frames with the integrated images allowed the determination of precisely how the EPID behaved during regular operation as well as when a beam interrupt was triggered. The ability of the EPID to reliably monitor a treatment in the presence of beam interrupts was tested by comparing the difference between the interrupt and non-interrupt images. The interrupted images acquired in integrated acquisition mode displayed unanticipated behaviour in the region of the image where the leaves were located when the beam interrupt was triggered. Differences greater than 5% were observed as a result of the interrupt in some cases, with the discrepancies occurring in a non-uniform manner across the imager. The differences measured were not repeatable from one measurement to another. Examination of the individual frames showed that the EPID was consistently losing a small amount of dose at the termination of every exposure. Inclusion of one additional frame in every image rectified the unexpected behaviour, reducing the differences to 1% or less. Although integrated EPID images nominally capture the entire dose delivered during an exposure, a small amount of dose is consistently being lost at the end of every exposure. The amount of missing dose is random, depending on the exact beam termination time within a frame. Inclusion of an extra frame at the end of each exposure effectively rectifies the problem, making the EPID more suitable for clinical dosimetry applications. The authors received support from Varian Medical Systems in the form of software and equipment loans as well as technical support. © 2012 American Association of Physicists in Medicine.

CD47-ligation induced cell death in T-acute lymphoblastic leukemia.

PubMed

Leclair, Pascal; Liu, Chi-Chao; Monajemi, Mahdis; Reid, Gregor S; Sly, Laura M; Lim, Chinten James

2018-05-10

CD47 is a cell-surface marker well recognized for its anti-phagocytic functions. As such, an emerging avenue for targeted cancer therapies involves neutralizing the anti-phagocytic function using monoclonal antibodies (mAbs) to enhance tumour cell immunogenicity. A lesser known consequence of CD47 receptor ligation is the direct induction of tumour cell death. While several mAbs and their derivatives with this property have been studied, the best characterized is the commercially available mAb B6H12, which requires immobilization for induction of cell death. Here, we describe a commercially available mAb, CC2C6, which induces T-cell acute lymphoblastic leukemia (ALL) cell death in soluble form. Soluble CC2C6 induces CD47-dependent cell death in a manner consistent with immobilized B6H12, which is characterized by mitochondrial deficiencies but is independent of caspase activation. Titration studies indicated that CC2C6 shares a common CD47-epitope with B6H12. Importantly, CC2C6 retains the anti-phagocytic neutralizing function, thus possessing dual anti-tumour properties. Although CD47-ligation induced cell death occurs in a caspase-independent manner, CC2C6 was found to stimulate increases in Mcl-1 and NOXA levels, two Bcl-2 family proteins that govern the intrinsic apoptosis pathway. Further analysis revealed that the ratio of Mcl-1:NOXA were minimally altered for cells treated with CC2C6, in comparison to cells treated with agents that induced caspase-dependent apoptosis which alter this ratio in favour of NOXA. Finally, we found that CC2C6 can synergize with low dose chemotherapeutic agents that induce classical apoptosis, giving rise to the possibility of an effective combination treatment with reduced long-term sequelae associated with high-dose chemotherapies in childhood ALL.

Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells.

PubMed

Seo, Hye-Sook; Jo, Jae Kyung; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; Kim, Hyo In; Kang, Soo-Yeon; Lee, Kang Min; Nam, Koong Won; Park, Namkyu; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

2015-10-23

Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer. © 2015 Authors.

Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells

PubMed Central

Seo, Hye-Sook; Jo, Jae Kyung; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; in Kim, Hyo; Kang, Soo-yeon; Lee, Kang min; Nam, Koong Won; Park, Namkyu; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

2015-01-01

Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer. PMID:26500281

Effects of Atmospheric Pressure Plasmas on Isolated and Cellular DNA—A Review

PubMed Central

Arjunan, Krishna Priya; Sharma, Virender K.; Ptasinska, Sylwia

2015-01-01

Atmospheric Pressure Plasma (APP) is being used widely in a variety of biomedical applications. Extensive research in the field of plasma medicine has shown the induction of DNA damage by APP in a dose-dependent manner in both prokaryotic and eukaryotic systems. Recent evidence suggests that APP-induced DNA damage shows potential benefits in many applications, such as sterilization and cancer therapy. However, in several other applications, such as wound healing and dentistry, DNA damage can be detrimental. This review reports on the extensive investigations devoted to APP interactions with DNA, with an emphasis on the critical role of reactive species in plasma-induced damage to DNA. The review consists of three main sections dedicated to fundamental knowledge of the interactions of reactive oxygen species (ROS)/reactive nitrogen species (RNS) with DNA and its components, as well as the effects of APP on isolated and cellular DNA in prokaryotes and eukaryotes. PMID:25642755

ω-Conotoxin GVIA Mimetics that Bind and Inhibit Neuronal Cav2.2 Ion Channels

PubMed Central

Tranberg, Charlotte Elisabet; Yang, Aijun; Vette, Irina; McArthur, Jeffrey R.; Baell, Jonathan B.; Lewis, Richard J.; Tuck, Kellie L.; Duggan, Peter J.

2012-01-01

The neuronal voltage-gated N-type calcium channel (Cav2.2) is a validated target for the treatment of neuropathic pain. A small library of anthranilamide-derived ω-Conotoxin GVIA mimetics bearing the diphenylmethylpiperazine moiety were prepared and tested using three experimental measures of calcium channel blockade. These consisted of a 125I-ω-conotoxin GVIA displacement assay, a fluorescence-based calcium response assay with SH-SY5Y neuroblastoma cells, and a whole-cell patch clamp electrophysiology assay with HEK293 cells stably expressing human Cav2.2 channels. A subset of compounds were active in all three assays. This is the first time that compounds designed to be mimics of ω-conotoxin GVIA and found to be active in the 125I-ω-conotoxin GVIA displacement assay have also been shown to block functional ion channels in a dose-dependent manner. PMID:23170089

Effects of atmospheric pressure plasmas on isolated and cellular DNA-a review.

PubMed

Arjunan, Krishna Priya; Sharma, Virender K; Ptasinska, Sylwia

2015-01-29

Atmospheric Pressure Plasma (APP) is being used widely in a variety of biomedical applications. Extensive research in the field of plasma medicine has shown the induction of DNA damage by APP in a dose-dependent manner in both prokaryotic and eukaryotic systems. Recent evidence suggests that APP-induced DNA damage shows potential benefits in many applications, such as sterilization and cancer therapy. However, in several other applications, such as wound healing and dentistry, DNA damage can be detrimental. This review reports on the extensive investigations devoted to APP interactions with DNA, with an emphasis on the critical role of reactive species in plasma-induced damage to DNA. The review consists of three main sections dedicated to fundamental knowledge of the interactions of reactive oxygen species (ROS)/reactive nitrogen species (RNS) with DNA and its components, as well as the effects of APP on isolated and cellular DNA in prokaryotes and eukaryotes.

Characterization of recombinant human HBP/CAP37/azurocidin, a pleiotropic mediator of inflammation-enhancing LPS-induced cytokine release from monocytes.

PubMed

Rasmussen, P B; Bjørn, S; Hastrup, S; Nielsen, P F; Norris, K; Thim, L; Wiberg, F C; Flodgaard, H

1996-07-15

Neutrophil-derived heparin-binding protein (HBP) is a strong chemoattractant for monocytes. We report here for the first time the expression of recombinant HBP. A baculovirus containing the human HBP cDNA mediated in insect cells the secretion of a 7-residue N-terminally extended HBP form (pro-HBP). Deletion of the pro-peptide-encoding cDNA sequence resulted in correctly processed HBP at the N-terminus. Electrospray mass spectrum analysis of recombinant HBP yielded a molecular weight of 27.237 +/- 3 amu. Consistent with this mass is a HBP form of 225 amino acids (mature part +3 amino acid C-terminal extension). The biological activity of recombinant HBP was confirmed by its chemotactic action towards monocytes. Furthermore, we have shown that recombinant HBP stimulates in a dose-dependent manner the lipopolysaccharide (LPS)-induced cytokine release from human monocytes.

Bedtime Routines for Young Children: A Dose-Dependent Association with Sleep Outcomes

PubMed Central

Mindell, Jodi A.; Li, Albert M.; Sadeh, Avi; Kwon, Robert; Goh, Daniel Y.T.

2015-01-01

Background: Establishment of a consistent bedtime routine (the activities that occur right before lights out) is often recommended as part of healthy sleep habits. However, no studies have investigated the dose-dependent association of a bedtime routine with sleep outcomes, especially in young children for whom they are particularly recommended. Thus, the aim of this study was to examine the associations of a consistent bedtime routine with sleep outcomes in young children (ages 0 through 5 y) in a large global sample and assess whether there is a dose-dependent relationship between the frequency of a bedtime routine both concurrently and retrospectively with sleep outcomes. Participants: Mothers of 10,085 children (Australia-New Zealand, Canada, China, Hong Kong, India, Japan, Korea, Malaysia, Philippines, Singapore, Thailand, United Kingdom, United States) completed the Brief Infant/Child Sleep Questionnaire. Results: A consistent bedtime routine was associated with better sleep outcomes, including earlier bedtimes, shorter sleep onset latency, reduced night wakings, and increased sleep duration. Decreased parent-perceived sleep problems and daytime behavior problems were also related to institution of a regular bedtime routine. Furthermore, there was a dose-dependent relationship, with better outcomes associated with increased “doses” of having a bedtime routine, both currently and retrospectively, and was found within both predominantly Asian and predominantly Caucasian cultural regions. Conclusions: These results indicate that having a regular nightly bedtime routine is associated with improved sleep in young children, and suggests that the more consistently a bedtime routine is instituted and the younger started the better. Citation: Mindell JA, Li AM, Sadeh A, Kwon R, Goh DY. Bedtime routines for young children: a dose-dependent association with sleep outcomes. SLEEP 2015;38(5):717–722. PMID:25325483

Assessing The Impact Of Cancer Therapies On Ovarian Reserve

PubMed Central

Gracia, Clarisa R.; Sammel, Mary D.; Freeman, Ellen; Prewitt, Maureen; Carlson, Claire; Ray, Anushree; Vance, Ashley; Ginsberg, Jill P.

2013-01-01

Objective To determine whether measures of ovarian reserve differ between females exposed to cancer therapies in a dose-dependent manner as compared to healthy controls of similar age and late-reproductive age. Design Cross-sectional analysis of data from a prospective cohort study Setting University Medical Center Patients 71 cancer survivors age 15-39; 67 healthy, similarly aged unexposed subjects; 69 regularly menstruating women of late-reproductive age (40-52 years). Interventions: None Main Outcome measures Early follicular phase hormones (FSH, Estradiol, Inhibin B, AMH) and ovarian ultrasound measurements (ovarian volume and Antral Follicle Counts) were compared using multivariable linear regression. Results In adjusted models, FSH, AMH and AFC differed between exposed vs. unexposed (FSH 11.12mIU/ml vs. 7.25mIU/ml, p=0.001; AMH 0.81ng/ml vs. 2.85ng/ml, p<0.001; AFC: 14.55 vs. 27.20, p<0.001. In participants with an FSH<10, survivors had lower levels of AMH and AFC compared to controls. Alkylating agent dose score was associated with increased levels of FSH (p= 0.016) and decreased levels of AMH (p=0.003). Exposure to pelvic radiation was associated with impairment in FSH, AMH, AFC and ovarian volume. AMH was similar in women previously exposed to high-dose cancer therapy and 40-42 year old controls. Conclusions Measures of ovarian reserve are impaired in a dose-dependent manner among cancer survivors compared to unexposed females of similar age. Reproductive hormone levels in menstruating survivors exposed to high-dose therapy are similar to late-reproductive women. The predictive value of measures for pregnancy and menopause must be studied. PMID:22137491

Chronic administration of phenytoin induces efflux transporter overexpression in rats.

PubMed

Alvariza, Silvana; Fagiolino, Pietro; Vázquez, Marta; Feria-Romero, Iris; Orozco-Suárez, Sandra

2014-12-01

Efflux transporters overexpression has been proposed as one of the responsible mechanism for refractory epilepsy by preventing access of the antiepileptic drug to the brain. In this work we investigated whether phenytoin (PHT), could induce efflux transporters overexpression, at different biological barriers and to evaluate the implication it could have on its pharmacokinetics and therapeutic/toxic response. Forty-two adult females Sprague Dawley divided in five groups were treated with oral doses of 25, 50 and 75mg/kg/6h of PHT for 3 days and two additionally groups were treated with intraperitoneal (ip) doses of 25mg/kg/6h or 100mg/kg/24h. At day 4 PHT plasma concentrations were measured and, obtained several organs, brain, parotid gland, liver and duodenum in which were analyzed for the Pgp expression. At day 4 PHT plasma concentrations were measured and several tissues: brain, parotid gland, liver and duodenum were obtained in order to analyze Pgp expression. In order to evaluate the oral bioavailability of PHT, two groups were administered with oral or intraperitoneal doses of 100mg/kg and plasma level were measured. An induction of the expression of efflux transporter mediated by phenytoin in a concentration-and-time dependent manner was found when increasing oral and ip doses of phenytoin, One week after the interruption of ip treatment a basal expression of transporters was recovered. Overexpression of efflux transporters can be mediated by inducer agents like PHT in a local-concentration dependent manner, and it is reversible once the substance is removed from the body. The recovery of basal Pgp expression could allow the design of dosing schedules that optimize anticonvulsant therapy. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Hormetic effects of noncoplanar PCB exposed to human lung fibroblast cells (HELF) and possible role of oxidative stress.

PubMed

Hashmi, Muhammad Zaffar; Khan, Kiran Yasmin; Hu, Jinxing; Naveedullah; Su, Xiaomei; Abbas, Ghulam; Yu, Chunna; Shen, Chaofeng

2015-12-01

Hormesis, a biphasic dose-response phenomenon, which is characterized by stimulation of an end point at a low-dose and inhibition at a high-dose. In the present study we used human lungs fibroblast (HELF) cells as a test model to evaluate the role of oxidative stress (OS) in hormetic effects of non coplanar PCB 101. Results from 3-(4,5-dime-thylthiazol-2-yl)-2,5-diphenyltetrazo-lium bromide (MTT) assay indicated that PCB101 at lower concentrations (10(-5) to 10(-1) μg mL(-1) ) stimulated HELF cell proliferation and inhibited at high concentrations (1, 5, 10, and 20 μg mL(-1) ) in a dose- and time-dependent manner. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) (except 48 h) showed a significant increase at higher concentrations of PCB 101 than those at the lower concentrations with the passage of time. Antioxidant enzymes such as glutathione peroxidase (GSH-Px) exhibited decreasing trends in dose and time dependent manner. Lipid peroxidation assay resulted in a significant increase (P < 0.05) of MDA level in PCB 101-treated HELF cells compared with controls, suggesting that OS plays a key role in PCB 101-induced toxicity. Comet assay indicated a significant increase in genotoxicity at higher concentrations of PCB 101 exposure compared to lower concentrations. Overall, we found that HELF cell proliferation was higher at low ROS level and vice versa, which revealed activation of cell signaling-mediated hormetic mechanisms. The results suggested that PCB 101 has hormetic effects to HELF cells and these were associated with oxidative stress. © 2014 Wiley Periodicals, Inc.

Therapeutic effect of umbelliferon-α-D-glucopyranosyl-(2(I)→1(II))-α-D-glucopyranoside on adjuvant-induced arthritic rats.

PubMed

Kumar, Vikas; Anwar, Firoz; Verma, Amita; Mujeeb, Mohd

2015-06-01

The aim and objective of the present investigation was to evaluate the antiarthritic and antioxidant effect of umbelliferon-α-D-glucopyranosyl-(2I→1II)-α-D-glucopyranoside (UFD) in chemically induced arthritic rats. The different doses of the UFD were tested against the turpentine oil (TO), formaldehyde induced acute arthritis and complete fruend's adjuvant (CFA) induced chronic arthritis in Wistar rats. Arthritic assessment and body weight was measured at regular interval till 28 days. On day 28, all the groups animals were anaesthetized, blood were collected from the puncturing the ratro orbital and estimated the hematological parameters. The animals were sacrificed; synovial tissue was extracted and estimated the malonaldehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx) and superoxide dismutase (SOD). The different doses of the UFD showed the protective effect against turpentine oil, formaldehyde induced acute arthritis and CFA induced chronic arthritis at dose dependent manner. Acute model of arthritis such as TOand formaldehyde induced inflammation due to releasing of the inflammatory mediators; significantly inhibited by the UFD at dose dependent manner. CFA induced arthritic rats treated with the different doses of the UFD showed the inhibitory effect on the delayed increase in joint diameter as seen in arthritic control group rats. UFD significantly improved the arthritic index, body weight and confirmed the antiarthritic effect. UFD showed the effect on the hematological parameter such as improved the level of the RBC, Hb and decline the level of the EBC, ESR and confirmed the immune suppressive effect. UFD significantly improved the level of the endogenous antioxidant and confirmed the antioxidant effect. This present investigation suggests that the UFD has prominent antiarthritic impact which can be endorsed to its antiarthritic and antioxidant effects.

Dopamine modulates male sexual behavior in Japanese quail in part via actions on noradrenergic receptors.

PubMed

Cornil, Charlotte A; Dejace, Christel; Ball, Gregory F; Balthazart, Jacques

2005-08-30

In rats, dopamine (DA) facilitates male sexual behavior through its combined action on D1- and D2-like receptors, in the medial preoptic area (MPOA) as well as other brain areas. In Japanese quail, systemic injections of dopaminergic drugs suggested a similar pharmacology but central injections have never been performed. Recent electrophysiological experiments demonstrated that DA effects in the MPOA of quail are mediated mainly through the activation of alpha2-noradrenergic receptors. Previous studies of DA action on behavior used specific dopaminergic agonists/antagonists and therefore unintentionally avoided the potential cross-reaction with alpha2-receptors. The present study was thus designed to investigate directly the effects of DA on male sexual behavior and to test whether the interaction of DA with heterologous receptors affects this behavior. Intracerebroventricular (i.c.v.) injection of DA or NE inhibited copulation in a dose-dependent manner. Systemic injections of yohimbine, an alpha2-noradrenergic antagonist, modulated copulation in a bimodal manner depending on the dose injected. Interestingly, a behaviorally ineffective dose of yohimbine markedly reduced the inhibitory effects of DA when injected 15min before. Together, these results show for the first time that i.c.v. injections of DA itself inhibit male sexual behavior in quail and suggest that the interaction of DA with alpha2-receptors has behavioral significance.

Anti-tumor effects and apoptosis induction by Realgar bioleaching solution in Sarcoma-180 cells in vitro and transplanted tumors in mice in vivo.

PubMed

Xie, Qin-Jian; Cao, Xin-Li; Bai, Lu; Wu, Zheng-Rong; Ma, Ying-Ping; Li, Hong-Yu

2014-01-01

Realgar which contains arsenic components has been used in traditional Chinese medicine (TCM) as an anticancer drug. However, neither Realgar nor its formula are soluble in water. As a result, high dose of Realgar has to be administered to achieve an effective blood medicine concentration, and this is associated with adverse side effects. The objective of the present study was to increase the solubility of a formula using hydrometallurgy technology as well as investigating its effects on in vitro and in vivo cell proliferation and apoptosis in Sarcoma-180 cell line. Antiproliferative activity of Realgar Bioleaching Solution (RBS) was evaluated by MTT assay. Further, effects of RBS on cell proliferation and apoptosis were studied using flow cytometry and transmission electron microscopy. Kunming mice were administered RBS in vivo, where arsenic specifically targeted solid tumors. The results indicated that RBS extract potently inhibited the tumor growth of Sarcoma-180 cell line in a dose-dependent manner. Flow cytometry and transmission electron microscopy further indicated that RBS significantly induced cell apoptosis through the inhibition of cell cycle pathway in a dose-dependent manner. Further, on RBS administration to mice, arsenic was specifically targeted to solid tumors RBS could substitute for traditional Realgar or its formula to work as a potent tool in cancer treatment.

Effects of acute phencyclidine administration on arginine metabolism in the hippocampus and prefrontal cortex in rats.

PubMed

Knox, Logan T; Jing, Yu; Collie, Nicola D; Zhang, Hu; Liu, Ping

2014-06-01

Phencyclidine (PCP), a non-competitive N-methyl-d-aspartate glutamate receptor antagonist, induces schizophrenic symptoms in healthy individuals, and altered arginine metabolism has been implicated in schizophrenia. The present study investigated the effects of a single subcutaneous injection of PCP (2, 5 or 10 mg/kg) on arginine metabolism in the sub-regions of the hippocampus and prefrontal cortex in male young adult Sprague-Dawley rats. Animals' general behaviour was assessed in the open field apparatus 30 min after the treatment, and the brain tissues were collected at the time point of 60 min post-treatment. Behaviourally, PCP resulted in reduced exploratory activity in a dose-dependent manner, and severe stereotype behaviour and ataxia at the highest dose. Neurochemically, PCP significantly altered the nitric oxide synthase and arginase activities, the l-arginine, agmatine, spermine, glutamate and GABA levels, and the glutamine/glutamate and glutamate/GABA ratios in a dose-dependent and/or region-specific manner. Cluster analyses showed that l-arginine and its main metabolites l-citrulline, l-ornithine and agmatine formed distinct groups, which changed as a function of PCP mainly in the hippocampus. Multiple regression analysis revealed significant neurochemical-behavioural correlations. These results demonstrate, for the first time, that a single acute administration of PCP affects animals' behaviour and arginine metabolism in the brain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Curcumin Blocks Naproxen-Induced Gastric Antral Ulcerations through Inhibition of Lipid Peroxidation and Activation of Enzymatic Scavengers in Rats.

PubMed

Kim, Jeong-Hwan; Jin, Soojung; Kwon, Hyun Ju; Kim, Byung Woo

2016-08-28

Curcumin is a polyphenol derived from the plant Curcuma longa, which is used for the treatment of diseases associated with oxidative stress and inflammation. The present study was undertaken to determine the protective effect of curcumin against naproxen-induced gastric antral ulcerations in rats. Different doses (10, 50, and 100 mg/kg) of curcumin or vehicle (curcumin, 0 mg/kg) were pretreated for 3 days by oral gavage, and then gastric mucosal lesions were caused by 80 mg/kg naproxen applied for 3 days. Curcumin significantly inhibited the naproxen-induced gastric antral ulcer area and lipid peroxidation in a dose-dependent manner. In addition, curcumin markedly increased activities of radical scavenging enzymes, such as superoxide dismutase (SOD), catalase, and glutathione peroxidase in a dose-dependent manner. Specifically, 100 mg/kg curcumin completely protected the gastric mucosa against the loss in the enzyme, resulting in a drastic increase of activities of radical scavenging enzymes up to more than the level of untreated normal rats. Histological examination obviously showed that curcumin prevents naproxen-induced gastric antral ulceration as a result of direct protection of the gastric mucosa. These results suggest that curcumin blocks naproxen-induced gastric antral ulcerations through prevention of lipid peroxidation and activation of radical scavenging enzymes, and it may offer a potential remedy of gastric antral ulcerations.

The macrocyclic peptide natural product CJ-15,208 is orally active and prevents reinstatement of extinguished cocaine-seeking behavior.

PubMed

Aldrich, Jane V; Senadheera, Sanjeewa N; Ross, Nicolette C; Ganno, Michelle L; Eans, Shainnel O; McLaughlin, Jay P

2013-03-22

The macrocyclic tetrapeptide natural product CJ-15,208 (cyclo[Phe-d-Pro-Phe-Trp]) exhibited both dose-dependent antinociception and kappa opioid receptor (KOR) antagonist activity after oral administration. CJ-15,208 antagonized a centrally administered KOR selective agonist, providing strong evidence it crosses the blood-brain barrier to reach KOR in the CNS. Orally administered CJ-15,208 also prevented both cocaine- and stress-induced reinstatement of extinguished cocaine-seeking behavior in the conditioned place preference assay in a time- and dose-dependent manner. Thus, CJ-15,208 is a promising lead compound with a unique activity profile for potential development, particularly as a therapeutic to prevent relapse to drug-seeking behavior in abstinent subjects.

28Si total body irradiation injures bone marrow hematopoietic stem cells via induction of cellular apoptosis

NASA Astrophysics Data System (ADS)

Chang, Jianhui; Feng, Wei; Wang, Yingying; Allen, Antiño R.; Turner, Jennifer; Stewart, Blair; Raber, Jacob; Hauer-Jensen, Martin; Zhou, Daohong; Shao, Lijian

2017-05-01

Long-term space mission exposes astronauts to a radiation environment with potential health hazards. High-energy charged particles (HZE), including 28Si nuclei in space, have deleterious effects on cells due to their characteristics with high linear energy transfer and dense ionization. The influence of 28Si ions contributes more than 10% to the radiation dose equivalent in the space environment. Understanding the biological effects of 28Si irradiation is important to assess the potential health hazards of long-term space missions. The hematopoietic system is highly sensitive to radiation injury and bone marrow (BM) suppression is the primary life-threatening injuries after exposure to a moderate dose of radiation. Therefore, in the present study we investigated the acute effects of low doses of 28Si irradiation on the hematopoietic system in a mouse model. Specifically, 6-month-old C57BL/6 J mice were exposed to 0.3, 0.6 and 0.9 Gy 28Si (600 MeV) total body irradiation (TBI). The effects of 28Si TBI on BM hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were examined four weeks after the exposure. The results showed that exposure to 28Si TBI dramatically reduced the frequencies and numbers of HSCs in irradiated mice, compared to non-irradiated controls, in a radiation dose-dependent manner. In contrast, no significant changes were observed in BM HPCs regardless of radiation doses. Furthermore, irradiated HSCs exhibited a significant impairment in clonogenic ability. These acute effects of 28Si irradiation on HSCs may be attributable to radiation-induced apoptosis of HSCs, because HSCs, but not HPCs, from irradiated mice exhibited a significant increase in apoptosis in a radiation dose-dependent manner. However, exposure to low doses of 28Si did not result in an increased production of reactive oxygen species and DNA damage in HSCs and HPCs. These findings indicate that exposure to 28Si irradiation leads to acute HSC damage.

Elevated Radiation Exposure Associated With Above Surface Flat Detector Mini C-Arm Use.

PubMed

Martin, Dennis P; Chapman, Talia; Williamson, Christopher; Tinsley, Brian; Ilyas, Asif M; Wang, Mark L

2017-11-01

This study aims to test the hypothesis that: (1) radiation exposure is increased with the intended use of Flat Surface Image Intensifier (FSII) units above the operative surface compared with the traditional below-table configuration; (2) this differential increases in a dose-dependent manner; and (3) radiation exposure varies with body part and proximity to the radiation source. A surgeon mannequin was seated at a radiolucent hand table, positioned for volar distal radius plating. Thermoluminescent dosimeters measured exposure to the eyes, thyroid, chest, hand, and groin, for 1- and 15-minute trials from a mini C-arm FSII unit positioned above and below the operating surface. Background radiation was measured by control dosimeters placed within the operating theater. At 1-minute of exposure, hand and eye dosages were significantly greater with the flat detector positioned above the table. At 15-minutes of exposure, hand radiation dosage exceeded that of all other anatomic sites with the FSII in both positions. Hand exposure was increased in a dose-dependent manner with the flat detector in either position, whereas groin exposure saw a dose-dependent only with the flat detector beneath the operating table. These findings suggest that the surgeon's hands and eyes may incur greater radiation exposure compared with other body parts, during routine mini C-arm FSII utilization in its intended position above the operating table. The clinical impact of these findings remains unclear, and future long-term radiation safety investigation is warranted. Surgeons should take precautions to protect critical body parts, particularly when using FSII technology above the operating with prolonged exposure time.

In vitro anticancer property of a novel thalidomide analogue through inhibition of NF-kappaB activation in HL-60 cells.

PubMed

Li, Min; Sun, Wan; Yang, Ya-ping; Xu, Bo; Yi, Wen-yuan; Ma, Yan-xia; Li, Zhong-jun; Cui, Jing-rong

2009-01-01

To investigate the anticancer property and possible mechanism of action of a novel sugar-substituted thalidomide derivative (STA-35) on HL-60 cells in vitro. TNF-alpha-induced NF-kappaB activation was determined using a reporter gene assay. The MTT assay was used to measure cytotoxicity of the compound. The appearance of apoptotic Sub-G1 cells was detected by flow cytometry analysis. PARP cleavage and protein expression of NF-kappaB p65 and its inhibitor IkappaB were viewed by Western blotting. TA-35 (1-20 micromol/L) suppressed TNF-alpha-induced NF-kappaB activation in transfected cells (HEK293/pNiFty-SEAP) in a dose- (1-20 micromol/L) and time-dependent (0-48 h) manner. It was also shown that STA-35 exerted a dose-dependent inhibitory effect on HL-60 cell proliferation with an IC(50) value of 9.05 micromol/L. In addition, STA-35 induced apoptosis in HL-60 cells, as indicated by the appearance of a Sub-G1 peak in the cell cycle distribution, as well as poly ADP-ribose polymerase (PARP) cleavage. Subsequently, both NF-kappaB p65 and its inhibitor IkappaB gradually accumulated in cytoplasmic extracts in a dose- and time-dependent manner, indicating the blockage of NF-kappaB translocation induced by TNF-alpha from the cytoplasm to the nucleus. A novel sugar-substituted thalidomide derivative, STA-35, is potent toward HL-60 cells in vitro and induces apoptosis by the suppression of NF-kappaB activation.

Dose-dependent bioavailability indicators for curcumin and two of its novel derivatives.

PubMed

Abd el Aziz, Mohamed; El-Asmer, Mohamed; Rezq, Ameen; Al-Malki, Abdulrahman; Kumosani, Taha; Fouad, Hanan; Ahmed, Hanan; Taha, Fatma; Hassouna, Amira; Hafez, Hafez

2014-01-01

Novel water-soluble curcumin derivatives have been developed to overcome low in vivo bioavailability of curcumin. The aim of this work is to assess the potential utility of certain downstream targets as bioavailability indicators of systemic activity of pure curcumin and two novel water-soluble curcumin derivatives (NCD) by constructing dose-dependent response curves and to prove whether this novel curcumin derivatives retained, improved, or abolished biological activity of pure curcumin when applied in vivo. Pure curcumin (CUR), curcumin-carboxy derivative (NCD-1), and curcumin protein conjugate (NCD-2) were administered orally to rats at escalating doses: 37, 74, 148, and 296 μM/kg body weight, respectively. Plasma levels of GST activity, cavernous tissue levels of cGMP, and enzymatic activity of both HO-1 and GST were assessed one and half and 24 hours after oral administration of curcumin formulae. This study showed that there was a progressive elevation of cavernous tissue levels of cGMP and enzymatic activity of both HO-1 and GST in a dose-dependent manner that was maintained for 24 h with CUR, NCD-1, and NCD-2. Plasma GST activity was decreased by the lowest doses on the curve. The three dose-dependent bioavailability indicators as surrogates of curcumin and two of its novel derivatives are valid in the studied range of concentration and extended time. The novel curcumin derivatives still conserve with improvement the biological activity of natural curcumin when applied in vivo. © 2013 International Union of Biochemistry and Molecular Biology.

Dose Response of Endotoxin on Hepatocyte and Muscle Mitochondrial Respiration In Vitro

PubMed Central

Brandt, Sebastian; Porta, Francesca; Jakob, Stephan M.; Takala, Jukka; Djafarzadeh, Siamak

2015-01-01

Introduction. Results on mitochondrial dysfunction in sepsis are controversial. We aimed to assess effects of LPS at wide dose and time ranges on hepatocytes and isolated skeletal muscle mitochondria. Methods. Human hepatocellular carcinoma cells (HepG2) were exposed to placebo or LPS (0.1, 1, and 10 μg/mL) for 4, 8, 16, and 24 hours and primary human hepatocytes to 1 μg/mL LPS or placebo (4, 8, and 16 hours). Mitochondria from porcine skeletal muscle samples were exposed to increasing doses of LPS (0.1–100 μg/mg) for 2 and 4 hours. Respiration rates of intact and permeabilized cells and isolated mitochondria were measured by high-resolution respirometry. Results. In HepG2 cells, LPS reduced mitochondrial membrane potential and cellular ATP content but did not modify basal respiration. Stimulated complex II respiration was reduced time-dependently using 1 μg/mL LPS. In primary human hepatocytes, stimulated mitochondrial complex II respiration was reduced time-dependently using 1 μg/mL LPS. In isolated porcine skeletal muscle mitochondria, stimulated respiration decreased at high doses (50 and 100 μg/mL LPS). Conclusion. LPS reduced cellular ATP content of HepG2 cells, most likely as a result of the induced decrease in membrane potential. LPS decreased cellular and isolated mitochondrial respiration in a time-dependent, dose-dependent and complex-dependent manner. PMID:25649304

An attempt to evaluate the effect of vitamin K3 using as an enhancer of anticancer agents.

PubMed

Matzno, Sumio; Yamaguchi, Yuka; Akiyoshi, Takeshi; Nakabayashi, Toshikatsu; Matsuyama, Kenji

2008-06-01

The possibility of vitamin K3 (VK3) as an anticancer agent was assessed. VK3 dose-dependently diminished the cell viability (measured as esterase activity) with IC50 of 13.7 microM and Hill coefficient of 3.1 in Hep G2 cells. It also decreased the population of S phase and arrested cell cycle in the G2/M phase in a dose-dependent manner. G2/M arrest was regulated by the increment of cyclin A/cdk1 and cyclin A/cdk2 complex, and contrasting cyclin B/cdk1 complex decrease. Finally, combined application demonstrated that VK3 significantly enhanced the cytotoxicity of etoposide, a G2 phase-dependent anticancer agent, whereas it reduced the cytotoxic activity of irinotecan, a S phase-dependent agent. These findings suggest that VK3 induces G2/M arrest by inhibition of cyclin B/cdk1 complex formation, and is thus useful as an enhancer of G2 phase-dependent drugs in hepatic cancer chemotherapy.

Effects of irradiation source and dose level on quality characteristics of processed meat products

NASA Astrophysics Data System (ADS)

Ham, Youn-Kyung; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Kim, Yong-Jae; Choi, Yun-Sang; Song, Beom-Seok; Park, Jong-Heum; Kim, Cheon-Jei

2017-01-01

The effect of irradiation source (gamma-ray, electron-beam, and X-ray) and dose levels on the physicochemical, organoleptic and microbial properties of cooked beef patties and pork sausages was studied, during 10 days of storage at 30±1 °C. The processed meat products were irradiated at 0, 2.5, 5, 7.5, and 10 kGy by three different irradiation sources. The pH of cooked beef patties and pork sausages was unaffected by irradiation sources or their doses. The redness of beef patties linearly decreased with increasing dose level (P<0.05), obviously by e-beam irradiation compared to gamma-ray and X-ray (P<0.05). The redness of pork sausages was increased by gamma-ray irradiation, whereas it decreased by e-beam irradiation depending on absorbed dose level. No significant changes in overall acceptability were observed for pork sausages regardless of irradiation source (P>0.05), while gamma-ray irradiated beef patties showed significantly decreased overall acceptability in a dose-dependent manner (P<0.05). Lipid oxidation of samples was accelerated by irradiation depending on irradiation sources and dose levels during storage at 30 °C. E-beam reduced total aerobic bacteria of beef patties more effectively, while gamma-ray considerably decreased microbes in pork sausages as irradiation dose increased. The results of this study indicate that quality attributes of meat products, in particular color, lipid oxidation, and microbial properties are significantly influenced by the irradiation sources.

Dose-Dependent Effects of Theta Burst rTMS on Cortical Excitability and Resting-State Connectivity of the Human Motor System

PubMed Central

Nettekoven, Charlotte; Volz, Lukas J.; Kutscha, Martha; Pool, Eva-Maria; Rehme, Anne K.; Eickhoff, Simon B.; Fink, Gereon R.

2014-01-01

Theta burst stimulation (TBS), a specific protocol of repetitive transcranial magnetic stimulation (rTMS), induces changes in cortical excitability that last beyond stimulation. TBS-induced aftereffects, however, vary between subjects, and the mechanisms underlying these aftereffects to date remain poorly understood. Therefore, the purpose of this study was to investigate whether increasing the number of pulses of intermittent TBS (iTBS) (1) increases cortical excitability as measured by motor-evoked potentials (MEPs) and (2) alters functional connectivity measured using resting-state fMRI, in a dose-dependent manner. Sixteen healthy, human subjects received three serially applied iTBS blocks of 600 pulses over the primary motor cortex (M1 stimulation) and the parieto-occipital vertex (sham stimulation) to test for dose-dependent iTBS effects on cortical excitability and functional connectivity (four sessions in total). iTBS over M1 increased MEP amplitudes compared with sham stimulation after each stimulation block. Although the increase in MEP amplitudes did not differ between the first and second block of M1 stimulation, we observed a significant increase after three blocks (1800 pulses). Furthermore, iTBS enhanced resting-state functional connectivity between the stimulated M1 and premotor regions in both hemispheres. Functional connectivity between M1 and ipsilateral dorsal premotor cortex further increased dose-dependently after 1800 pulses of iTBS over M1. However, no correlation between changes in MEP amplitudes and functional connectivity was detected. In summary, our data show that increasing the number of iTBS stimulation blocks results in dose-dependent effects at the local level (cortical excitability) as well as at a systems level (functional connectivity) with a dose-dependent enhancement of dorsal premotor cortex-M1 connectivity. PMID:24828639

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

PubMed

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

2008-02-01

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

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

PubMed Central

Umysová, Dáša; Vítová, Milada; Doušková, Irena; Bišová, Kateřina; Hlavová, Monika; Čížková, Mária; Machát, Jiří; Doucha, Jiří; Zachleder, Vilém

2009-01-01

Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3) – strain SeIV, selenate (Na2SeO4) – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity. Our study provides a new insight into the impact of selenium on green algae, especially with regard to its toxicity and bioaccumulation. PMID:19445666

G2013 modulates TLR4 signaling pathway in IRAK-1 and TARF-6 dependent and miR-146a independent manner.

PubMed

Hajivalili, M; Pourgholi, F; Majidi, J; Aghebati-Maleki, L; Movassaghpour, A A; Samadi Kafil, H; Mirshafiey, A; Yousefi, M

2016-04-30

Inflammation is inseparable part of different diseases especially cancer and autoimmunity. During inflammation process toll like receptor 4(TLR4) responds to lipopolysaccharide (LPS), one of the bacterial components, and TLR4 signaling leads to interleukine-1 receptor associated kinase-1 (IRAK1) and tumor necrosis factor (TNF) receptor associated factor6 (TRAF6) activation which ultimately results in nuclear factor- ĸB (NF-ĸB) activation as the main transcription factor of inflammatory cytokines. Conversely, NF-ĸB over activation induces miR-146a in innate immune cells which can consequently reduce TRAF6, IRAK1, and NF-ĸB activation in a negative feedback. G2013 is a novel designed non-steroidal anti-inflammatory drug (NSAID) which was recently shown to be effective in experimental autoimmune encephalomyelitis (EAE) mouse model. The aim of this study was to evaluate G2013 effects on inflammatory (IRAK1 and TRAF6) and anti-inflammatory (miR-146a) factors of TLR4 signaling pathway. For this purpose, cytotoxicity of G2013 has been evaluated by MTT assay. Expression level of miR-146a in PBMCs and IRAK1 along with TRAF6 in HEK-293 TLR4 cells have been determined using real time PCR. Our results showed that IC50 of G2013 was 25μg/ml, thus 5 and 25 μg/ml concentrations used for further treatments as low dose and high dose concentrations. Our results showed that IRAK1 expression reduced between 5 to 8 fold after treatment by G2013 in a dose dependent manner (p<0.001). In parallel TRAF6 expression declined between 3 to 10 fold dose dependently (p<0.05). However, miR-146a expression was not affected after treatment with low dose and high dose of G2013. In conclusion our data showed that G2013 can regulate TLR4 signaling pathway during inflammation by reducing downstream signaling molecules, IRAK1 and TRAF6 without altering miR-146a expression.

Repeated dose 28-days oral toxicity study of Carica papaya L. leaf extract in Sprague Dawley rats.

PubMed

Afzan, Adlin; Abdullah, Noor Rain; Halim, Siti Zaleha; Rashid, Badrul Amini; Semail, Raja Hazlini Raja; Abdullah, Noordini; Jantan, Ibrahim; Muhammad, Hussin; Ismail, Zakiah

2012-04-10

Carica papaya L. leaves have been used in ethnomedicine for the treatment of fevers and cancers. Despite its benefits, very few studies on their potential toxicity have been described. The aim of the present study was to characterize the chemical composition of the leaf extract from 'Sekaki' C. papaya cultivar by UPLC-TripleTOF-ESI-MS and to investigate the sub-acute oral toxicity in Sprague Dawley rats at doses of 0.01, 0.14 and 2 g/kg by examining the general behavior, clinical signs, hematological parameters, serum biochemistry and histopathology changes. A total of twelve compounds consisting of one piperidine alkaloid, two organic acids, six malic acid derivatives, and four flavonol glycosides were characterized or tentatively identified in the C. papaya leaf extract. In the sub-acute study, the C. papaya extract did not cause mortality nor were treatment-related changes in body weight, food intake, water level, and hematological parameters observed between treatment and control groups. Some biochemical parameters such as the total protein, HDL-cholesterol, AST, ALT and ALP were elevated in a non-dose dependent manner. Histopathological examination of all organs including liver did not reveal morphological alteration. Other parameters showed non-significant differences between treatment and control groups. The present results suggest that C. papaya leaf extract at a dose up to fourteen times the levels employed in practical use in traditional medicine in Malaysia could be considered safe as a medicinal agent.

Myricetin and Quercetin Are Naturally-Occurring Co-substrates of Cyclooxygenases In Vivo1

PubMed Central

Bai, Hyoung-Woo; Zhu, Bao T.

2009-01-01

Bioflavonoids are ubiquitously present in the plant kingdom, and some of them are presently being sold as healthy dietary supplements around the world. Recently, it was shown that some of the dietary polyphenols were strong stimulators of the catalytic activity of cyclooxygenase I and II, resulting in increased formation of certain prostaglandin (PG) products in vitro and also in intact cells in culture. In the present study, we investigated the effect of two representative dietary compounds, quercetin and myricetin, on plasma and tissue levels of several PG products in normal Sprague-Dawley rats. We found that these two dietary bioflavonoids could strongly stimulate the formation of PG products in vivo in a time-dependent manner, and the stimulatory effect of these two bioflavonoids was dose-dependent with a unique biphasic pattern. At lower doses (<0.3 mg/kg b.w.), they strongly stimulated the formation of PGE2, but at higher doses (>0.3 mg/kg b.w.), there was a dose-dependent reduction of the stimulatory effect. These results provide support for the hypothesis that some of the bioflavonoids are naturally-occurring physiological co-substrates for the cyclooxygenases in vivo. PMID:19897347

Antioxidant, analgesic and anti-inflammatory activities of the methanolic extract of Piper betle leaves

PubMed Central

Alam, Badrul; Akter, Fahima; Parvin, Nahida; Sharmin Pia, Rashna; Akter, Sharmin; Chowdhury, Jesmin; Sifath-E-Jahan, Kazi; Haque, Ekramul

2013-01-01

Objective: The present study was designed to evaluate the antioxidant, analgesic, and anti-inflammatory activities of the methanolic extract of Piper betle leaves (MPBL). Materials and Methods: MPBL was evaluated for anti-inflammatory activity using carrageenan-induced hind paw edema model. Analgesic activity of MPBL was evaluated by hot plate, writhing, and formalin tests. Total phenolic and flavonoids content, total antioxidant activity, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, peroxynitrate (ONOO) as well as inhibition of total ROS generation, and assessment of reducing power were used to evaluate antioxidant potential of MPBL. Results: The extract of MPBL, at the dose of 100 and 200 mg/kg, produced a significant (p<0.05) increase in pain threshold in hot plate method whereas significantly (p<0.05) reduced the writhing caused by acetic acid and the number of licks induced by formalin in a dose-dependent manner. The same ranges of doses of MPBL caused significant (p<0.05) inhibition of carrageenan-induced paw edema after 4 h in a dose-dependent manner. In DPPH, ONOO-, and total ROS scavenging method, MPBL showed good antioxidant potentiality with the IC50 value of 16.33±1.02, 25.16±0.61 , and 41.72±0.48 µg/ml, respectively with a significant (p<0.05) good reducing power. Conclusion: The findings of the study suggested that MPBL has strong analgesic, anti-inflammatory, and antioxidant effects, conforming the traditional use of this plant for inflammatory pain alleviation to its antioxidant potentiality. PMID:25050265

Study on the diuretic activity of Euphorbia fusiformis Buch.-Ham. in albino rats.

PubMed

Ashok, B K; Bhat, Savitha D; Shukla, V J; Ravishankar, B

2011-07-01

The present study was undertaken to evaluate diuretic activity of Euphorbia fusiformis root powder in Wistar strain albino rats. Randomly selected animals were divided into three groups of six animals each. The root powder was suspended in distilled water and administered orally at a dose of 90 mg/kg therapeutically equivalent dose (TED) and 180 mg/kg (TED × 02) to overnight fasted rats. The diuretic activity was evaluated by determination of urine volume and urinary electrolyte concentrations. Test drug showed significant increase in urine volume and urinary electrolyte excretion in a dose-dependant manner. Thus, from this study, it can be concluded that roots of E. fusiformis possess diuretic activity.

Effects of Intra-Amygdala Infusion of CB1 Receptor Agonists on the Reconsolidation of Fear-Potentiated Startle

ERIC Educational Resources Information Center

Lin, Hui-Ching; Mao, Sheng-Chun; Gean, Po-Wu

2006-01-01

The cannabinoid CB1 receptor has been shown to be critically involved in the extinction of fear memory. Systemic injection of a CB1 receptor antagonist prior to extinction training blocked extinction. Conversely, administration of the cannabinoid uptake inhibitor AM404 facilitated extinction in a dose-dependent manner. Here we show that bilateral…

Osthole prevents cerebral ischemia-reperfusion injury via the Notch signaling pathway.

PubMed

Guan, Junhong; Wei, Xiangtai; Qu, Shengtao; Lv, Tao; Fu, Qiang; Yuan, Ye

2017-08-01

Stroke is a common cerebrovascular disease in aging populations, and constitutes the second highest principle cause of mortality and the principle cause of permanent disability, and ischemic stroke is the primary form. Osthole is a coumarin derivative extracted from the fruits of Cnidium monnieri (L.) Cusson. In this study, we established a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) in vivo and found that MCAO/R caused cerebral infarction, hippocampus neuronal injury and apoptosis, and also activated the Notch 1 signaling pathway. However, treatment with osthole further enhanced the activity of Notch 1 signaling and reduced the cerebral infarction as well as the hippocampus neuronal injury and apoptosis induced by MCAO/R in a dose-dependent manner. The same results were observed in a primary neuronal oxygen glucose deficiency/reperfusion (OGD/R) model in vitro, and the effect of osthole could be blocked by an inhibitor of Notch 1 signaling, N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester (DAPT). Therefore, we demonstrated that osthole injection prevented rat ischemia-reperfusion injury via activating the Notch 1 signaling pathway in vivo and in vitro in a dose-dependent manner, which may be significant for clinical treatment of ischemic stroke.

Anti-platelet activity of a three-finger toxin (3FTx) from Indian monocled cobra (Naja kaouthia) venom.

PubMed

Chanda, Chandrasekhar; Sarkar, Angshuman; Sistla, Srinivas; Chakrabarty, Dibakar

2013-11-22

A low molecular weight anti-platelet peptide (6.9 kDa) has been purified from Naja kaouthia venom and was named KT-6.9. MALDI-TOF/TOF mass spectrometry analysis revealed the homology of KT-6.9 peptide sequence with many three finger toxin family members. KT-6.9 inhibited human platelet aggregation process in a dose dependent manner. It has inhibited ADP, thrombin and arachidonic acid induced platelet aggregation process in dose dependent manner, but did not inhibit collagen and ristocetin induced platelet aggregation. Strong inhibition (70%) of the ADP induced platelet aggregation by KT-6.9 suggests competition with ADP for its receptors on platelet surface. Anti-platelet activity of KT-6.9 was found to be 25 times stronger than that of anti-platelet drug clopidogrel. Binding of KT-6.9 to platelet surface was confirmed by surface plasma resonance analysis using BIAcore X100. Binding was also observed by a modified sandwich ELISA method using anti-KT-6.9 antibodies. KT-6.9 is probably the first 3 FTx from Indian monocled cobra venom reported as a platelet aggregation inhibitor. Copyright © 2013 Elsevier Inc. All rights reserved.

Cadmium inhibits neurite outgrowth in differentiating human SH-SY5Y neuroblastoma cells.

PubMed

Pak, Eun Joo; Son, Gi Dong; Yoo, Byung Sun

2014-01-01

Cadmium, a highly ubiquitous heavy metal, is well known to induce neurotoxicity. However, the underlying mechanism of cadmium-mediated neurotoxicity remains unclear. We have studied cadmium inhibition of neurite outgrowth using human SH-SY5Y neuroblastoma cells induced to differentiate by all-trans-retinoic acid (RA). Cadmium, at a concentration of 3 μmol/L, had no significant effect on the viability of differentiating SH-SY5Y cells. However, the neurite outgrowth of the differentiating SH-SY5Y cells 48 hours after cadmium treatment (1-3 μmol/L cadmium) was significantly inhibited in a dose-dependent manner. Treatment of RA-stimulated differentiating SH-SY5Y cells with 1 to 3 μmol/L cadmium resulted in decreased level of cross-reactivities with 43-kDa growth-associated protein (GAP-43) in a dose-dependent manner. The reactive oxygen species (ROS) scavenger, NAC (N-acetyl-l-cysteine), recovered the expression of GAP-43 in cadmium-treated cells. The results indicate that cadmium is able to inhibit neurite outgrowth of differentiating SH-SY5Y cells and that this effect might result from ROS generation by cadmium. © The Author(s) 2014.

Effects of excess biotin administration on the growth and urinary excretion of water-soluble vitamins in young rats.

PubMed

Sawamura, Hiromi; Fukuwatari, Tsutomu; Shibata, Katsumi

2007-12-01

To determine the effects of excess biotin administration on growth and water-soluble vitamin metabolism, weaning rats were fed on a 20% casein diet containing 0.00002% biotin, or same diet with 0.04, 0.08, 0.10, 0.20, 0.50, 0.80 or 1.0% added biotin for 28 days. More than 0.08% biotin administration decreased the food intake and body weight gain compared with the levels in control rats. An accumulation of biotin in such tissues as the liver, brain and kidney increased in a dose-dependent manner, and the both bound and free biotin contents in the liver also increased in a dose-dependent manner. An excess administration of biotin did not affect the urinary excretion of other water-soluble vitamins, suggesting no effect on the metabolism of other water-soluble vitamins. The results of the food intake and body weight gain indicated that the lowest observed adverse effect level for young rats was 79.2 mg/kg body weight/day, while the no observed adverse effect level was 38.4 mg/kg/day. These results suggested immediately setting a tolerable upper intake level for biotin.

Lipotoxicity in HepG2 cells triggered by free fatty acids

PubMed Central

Yao, Hong-Rui; Liu, Jun; Plumeri, Daniel; Cao, Yong-Bing; He, Ting; Lin, Ling; Li, Yu; Jiang, Yuan-Ying; Li, Ji; Shang, Jing

2011-01-01

The goal of this study was to investigate the lipid accumulation and lipotoxicity of free fatty acids (FFAs) induced in HepG2 cells. HepG2 cells were co-incubated with various concentrations of FFAs for 24h and the intracellular lipid contents were observed by Oil Red O and Nile Red staining methods. The lipotoxicity of HepG2 cells were then detected by Hoechest 33342/PI, Annexin V-FITC/PI double-staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-di phenyltetrazolium bromide (MTT) experiment tests. The experiments showed a lipid accumulation and lipotoxicity by increasing FFA concentration gradients. Through cell morphological observation and quantitative analysis, FFAs have shown to increase in a dose-dependent manner compared with the control group. The data collected from hoechst 33342/PI, annexin V-FITC/PI double staining and also MTT experiments showed that cell apoptosis and necrosis significantly increased with increasing FFA concentrations. Apoptosis was not obvious in the 1 mM FFAs-treated group compared to the other two groups. In a certain concentration range, FFAs induced intracellular lipid accumulation and lipotoxicity of HepG2 cells in a dose-dependent manner. PMID:21654881

Exploration of intrinsic and extrinsic apoptotic pathways in zearalenone-treated rat sertoli cells.

PubMed

Xu, Ming-Long; Hu, Jin; Guo, Bao-Ping; Niu, Ya-Ru; Xiao, Cheng; Xu, Yin-Xue

2016-12-01

Zearalenone (ZEA) is a nonsteroidal estrogenic mycotoxin produced mainly by Fusarium. ZEA causes reproductive disorders and is both cytotoxic and genotoxic in animals; however, little is known regarding the molecular mechanism(s) leading to ZEA toxicity. Sertoli cells are somatic cells that support the development of spermatogenic cells. The objective of this study was to explore the effects of ZEA on the proliferation, apoptosis, and necrosis of rat Sertoli cells to uncover signaling pathways underlying ZEA cytotoxicity. ZEA reduced the proliferation of rat Sertoli cells in a dose-dependent manner, as indicated by a CCK8 assay, while flow cytometry revealed that ZEA caused both apoptosis and necrosis. Immunoblotting revealed that ZEA treatment increased the ratio of Bax/Bcl-2, as well as the expression of FasL and caspases-3, -8, and -9, in a dose-dependent manner. Collectively, these data suggest that ZEA induced apoptosis and necrosis in rat Sertoli cells via extrinsic and intrinsic apoptotic pathways. This study provides new insights into the molecular mechanisms by which ZEA exhibits cytotoxicity. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1731-1739, 2016. © 2015 Wiley Periodicals, Inc.

MET inhibitor PHA-665752 suppresses the hepatocyte growth factor-induced cell proliferation and radioresistance in nasopharyngeal carcinoma cells

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

Liu, Tongxin; Li, Qi; Sun, Quanquan

2014-06-20

Highlights: • We demonstrated that irradiation induced MET overexpression and activation. • The aberrant MET signal mediated by HGF induced proliferation and radioresistance of NPC cells. • MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. • PHA-665752 suppressed the three downstream pathway of HGF/MET signal in a dose-dependent manner. - Abstract: Although ionizing radiation (IR) has provided considerable improvements in nasopharyngeal carcinoma (NPC), in subsets of patients, radioresistance is still a major problem in the treatment. In this study, we demonstrated that irradiation induced MET overexpression and activation, and the aberrant MET signal mediatedmore » by hepatocyte growth factor (HGF) induced radioresistance. We also found that MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. Further investigation indicated that PHA-665752 suppressed the phosphorylation of the Akt, ERK1/2, and STAT3 proteins in a dose-dependent manner. Our data indicated that the combination of IR with a MET inhibitor, such as PHA-665752, might be a promising therapeutic strategy for NPC.« less

Ethanol immunosuppression in vitro

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

Kaplan, D.R.

Ethanol in concentrations equivalent to levels achieved by the ingestion of moderate to large amounts of alcoholic beverages has been shown to inhibit mitogen and anti-CD3 stimulated human T lymphocyte proliferation. This inhibition was monophasic suggesting that ethanol affected a single limiting component of T cell proliferation. In experiments designed to test the effect of ethanol on various aspects of proliferation, it was demonstrated that ethanol inhibited the capacity of exogenously supplied interleukin 2 to stimulate proliferation of T cells that had previously acquired interleukin 2 receptors in a monophasic, dose-dependent manner. Moreover, there was no suppression of interleukin 2more » production or interleukin 2 receptor acquisition. Thus, ethanol was shown to mediate immunosuppression by a mechanism specific to one component of proliferation. Additive inhibition of T cell proliferation was seen with ethanol plus cyclosporin A which inhibits interleukin 2 production. The level of inhibition with 250 ng/ml cyclosporin A alone was equivalent to the level seen with 62 ng/ml cyclosporin A plus 20 mM (94 mg%) ethanol. Ethanol also suppressed an immune effector mechanism. NK cytotoxicity was depressed in a monophasic, dose-dependent manner. Thus, ethanol might be considered as a possible adjunct in immunosuppressive therapy.« less

Dietary vitamin A regulates wingless-related MMTV integration site signaling to alter the hair cycle.

PubMed

Suo, Liye; Sundberg, John P; Everts, Helen B

2015-05-01

Alopecia areata (AA) is an autoimmune hair loss disease caused by a cell-mediated immune attack of the lower portion of the cycling hair follicle. Feeding mice 3-7 times the recommended level of dietary vitamin A accelerated the progression of AA in the graft-induced C3H/HeJ mouse model of AA. In this study, we also found that dietary vitamin A, in a dose dependent manner, activated the hair follicle stem cells (SCs) to induce the development and growth phase of the hair cycle (anagen), which may have made the hair follicle more susceptible to autoimmune attack. Our purpose here is to determine the mechanism by which dietary vitamin A regulates the hair cycle. We found that vitamin A in a dose-dependent manner increased nuclear localized beta-catenin (CTNNB1; a marker of canonical wingless-type Mouse Mammary Tumor Virus integration site family (WNT) signaling) and levels of WNT7A within the hair follicle bulge in these C3H/HeJ mice. These findings suggest that feeding mice high levels of dietary vitamin A increases WNT signaling to activate hair follicle SCs. © 2014 by the Society for Experimental Biology and Medicine.

Oolong tea prevents cardiomyocyte loss against hypoxia by attenuating p-JNK mediated hypertrophy and enhancing P-IGF1R, p-akt, and p-Badser136 activity and by fortifying NRF2 antioxidation system.

PubMed

Shibu, Marthandam Asokan; Kuo, Chia-Hua; Chen, Bih-Cheng; Ju, Da-Tong; Chen, Ray-Jade; Lai, Chao-Hung; Huang, Pei-Jane; Viswanadha, Vijaya Padma; Kuo, Wei-Wen; Huang, Chih-Yang

2018-02-01

Tea, the most widely consumed natural beverage has been associated with reduced mortality risk from cardiovascular disease. Oolong tea is a partially fermented tea containing high levels of catechins, their degree of oxidation varies between 20%-80% causing differences in their active metabolites. In this study we examined the effect of oolong tea extract (OTE) obtained by oxidation at low-temperature for short-time against hypoxic injury and found that oolong tea provides cyto-protective effects by suppressing the JNK mediated hypertrophic effects and by enhancing the innate antioxidant mechanisms in neonatal cardiomyocytes and in H9c2 cells. OTE effectively attenuates 24 h hypoxia-triggered cardiomyocyte loss by suppressing caspase-3-cleavage and apoptosis in a dose-dependent manner. OTE also enhances the IGFIR/p-Akt associated survival-mechanism involving the elevation of p-Bad ser136 in a dose-dependent manner to aid cellular adaptations against hypoxic challenge. The results show the effects and mechanism of Oolong tea to provide cardio-protective benefits during hypoxic conditions. © 2017 Wiley Periodicals, Inc.

Persimmon-Tannin, an α-Amylase Inhibitor, Retards Carbohydrate Absorption in Rats.

PubMed

Tsujita, Takahiro

2016-01-01

Inhibitors of carbohydrate-hydrolyzing enzymes play an important role in controlling postprandial blood glucose levels. Thus the effect of persimmon tannin on pancreatic α-amylase and intestinal α-glucosidase has been investigated. Persimmon tannin inhibits pancreatic α-amylase and intestinal α-glucosidase in a concentration-dependent manner with the 50% inhibition concentration (IC50) for amylase, maltase and sucrase being 1.7 μg/mL, 632 μg/mL and 308 μg/mL, respectively. The effect of persimmon-tannin extract on carbohydrate absorption in rats has also been investigated. Oral administration of persimmon tannin to normal rats fed cornstarch (2 g/kg body weight) significantly suppressed the increase in blood glucose levels and the area under the curve (AUC) after starch loading in a dose-dependent manner. The effective dose of persimmon tannin required to achieve 50% suppression of the rise in blood glucose level was estimated to be 300 mg/kg body weight. Administration of persimmon tannin to rats fed maltose or sucrose delayed the increase of blood glucose level and slightly suppressed AUC, but not significantly. These results suggest that persimmon tannin retards absorption of carbohydrate and reduces post-prandial hyperglycemia mainly through inhibition of α-amylase.

Pirfenidone induces intercellular adhesion molecule-1 (ICAM-1) down-regulation on cultured human synovial fibroblasts

PubMed Central

Kaneko, M; Inoue, H; Nakazawa, R; Azuma, N; Suzuki, M; Yamauchi, S; Margolin, S B; Tsubota, K; Saito, I

1998-01-01

Pirfenidone has been shown to modify some cytokine regulatory actions and inhibit fibroblast biochemical reactions resulting in inhibition of proliferation and collagen matrix synthesis by fibroblast. We have investigated the effect of pirfenidone on the expression of cell adhesion molecules. The synovial fibroblasts were treated with IL-1α in the presence or absence of pirfenidone (range 0–1000 μm), and assayed for the expression of adhesion molecules such as ICAM-1 and endothelial-leucocyte adhesion molecule-1 (E-selectin) by cell ELISA. Pirfenidone significantly down-regulated the expression of ICAM-1 on cultured synovial fibroblasts in a dose-dependent manner. In contrast, expression of E-selectin was not affected. Furthermore, we examined whether pirfenidone affects the cellular binding between cultured lymphocytes and IL-1α-stimulated synovial fibroblasts by in vitro binding assay and found their mutual binding was significantly suppressed in a dose-dependent manner by pirfenidone. It is speculated that down-regulation of ICAM-1 might be one of the novel mechanisms of action of pirfenidone. These data indicate a novel mechanism of action for pirfenidone to reduce the activation of synovial fibroblasts. PMID:9697986

Effects of rutin on acrylamide-induced neurotoxicity

PubMed Central

2014-01-01

Background Rutin is an important flavonoid that is consumed in the daily diet. The cytoprotective effects of rutin, including antioxidative, and neuroprotective have been shown in several studies. Neurotoxic effects of acrylamide (ACR) have been established in humans and animals. In this study, the protective effects of rutin in prevention and treatment of neural toxicity of ACR were studied. Results Rutin significantly reduced cell death induced by ACR (5.46 mM) in time- and dose-dependent manners. Rutin treatment decreased the ACR-induced cytotoxicity significantly in comparison to control (P <0.01, P < 0.001). Rutin (100 and 200 mg/kg) could prevent decrease of body weight in rats. In combination treatments with rutin (50, 100 and 200 mg/kg), vitamin E (200 mg/kg) and ACR, gait abnormalities significantly decreased in a dose-dependent manner (P < 0.01 and P < 0.001). The level of malondialdehyde significantly decreased in the brain tissue of rats in both preventive and therapeutic groups that received rutin (100 and 200 mg/kg). Conclusion It seems that rutin could be effective in reducing neurotoxicity and the neuroprotective effect of it might be mediated via antioxidant activity. PMID:24524427

Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation

PubMed Central

Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung

2013-01-01

The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-dependent manner. Rats were orally administered with nattokinase for 1 week, and their carotid arteries were exposed. Arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Nattokinase delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 160 mg/kg. In addition, a high dose (500 mg/kg) of nattokinase fully prevented the occlusion, as achieved with aspirin (30 mg/kg). The results indicate that nattokinase extracted from fermented soybean inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is suggested that nattokinase could be a good candidate without adverse effects for the improvement of blood flow. PMID:24396387

Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation.

PubMed

Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

2013-12-01

The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-dependent manner. Rats were orally administered with nattokinase for 1 week, and their carotid arteries were exposed. Arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Nattokinase delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 160 mg/kg. In addition, a high dose (500 mg/kg) of nattokinase fully prevented the occlusion, as achieved with aspirin (30 mg/kg). The results indicate that nattokinase extracted from fermented soybean inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is suggested that nattokinase could be a good candidate without adverse effects for the improvement of blood flow.

Unheated Cannabis sativa extracts and its major compound THC-acid have potential immuno-modulating properties not mediated by CB1 and CB2 receptor coupled pathways.

PubMed

Verhoeckx, Kitty C M; Korthout, Henrie A A J; van Meeteren-Kreikamp, A P; Ehlert, Karl A; Wang, Mei; van der Greef, Jan; Rodenburg, Richard J T; Witkamp, Renger F

2006-04-01

There is a great interest in the pharmacological properties of cannabinoid like compounds that are not linked to the adverse effects of Delta(9)-tetrahydrocannabinol (THC), e.g. psychoactive properties. The present paper describes the potential immuno-modulating activity of unheated Cannabis sativa extracts and its main non-psychoactive constituent Delta(9)-tetrahydrocanabinoid acid (THCa). By heating Cannabis extracts, THCa was shown to be converted into THC. Unheated Cannabis extract and THCa were able to inhibit the tumor necrosis factor alpha (TNF-alpha) levels in culture supernatants from U937 macrophages and peripheral blood macrophages after stimulation with LPS in a dose-dependent manner. This inhibition persisted over a longer period of time, whereas after prolonged exposure time THC and heated Cannabis extract tend to induce the TNF-alpha level. Furthermore we demonstrated that THCa and THC show distinct effects on phosphatidylcholine specific phospholipase C (PC-PLC) activity. Unheated Cannabis extract and THCa inhibit the PC-PLC activity in a dose-dependent manner, while THC induced PC-PLC activity at high concentrations. These results suggest that THCa and THC exert their immuno-modulating effects via different metabolic pathways.

Effects of Litchi chinensis fruit isolates on prostaglandin E2 and nitric oxide production in J774 murine macrophage cells

PubMed Central

2012-01-01

Background Litchi chinensis is regarded as one of the 'heating' fruits in China, which causes serious inflammation symptoms to people. Methods In the current study, the effects of isolates of litchi on prostaglandin E2 (PGE2) and nitric oxide (NO) production in J774 murine macrophage cells were investigated. Results The AcOEt extract (EAE) of litchi was found effective on stimulating PGE2 production, and three compounds, benzyl alcohol, hydrobenzoin and 5-hydroxymethyl-2-furfurolaldehyde (5-HMF), were isolated and identified from the EAE. Benzyl alcohol caused markedly increase in PGE2 and NO production, compared with lipopolysaccharide (LPS) as positive control, and in a dose-dependent manner. Hydrobenzoin and 5-HMF were found in litchi for the first time, and both of them stimulated PGE2 and NO production moderately in a dose-dependent manner. Besides, regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) mRNA expression and NF-κB (p50) activation might be involved in mechanism of the stimulative process. Conclusion The study showed, some short molecular compounds in litchi play inflammatory effects on human. PMID:22380404

Antinociceptive activity of a polysaccharide from the roots of Sophora flavescens.

PubMed

Jia, Ruimei; Li, Quancheng; Shen, Weixi; Zhang, Jiuwei; Zheng, Lihong; Wang, Guonian

2016-12-01

A polysaccharide (SFWP), with a molecular weight of 51kDa, was successfully purified from the roots of Sophora flavescens and the antinociceptive actions of SFWP were evaluated using acetic acid induced writhing, tail flick, and formalin tests in mice. GC-MS results showed that SFWP had a backbone composed of (1→2)-linked Glc, (1→2,6)-inkedGal and (1→3,6)-inked Man residues, which were terminated with (1→)-inked Xyl and (1→)-inked Ara at O-6 of (1→2,6)-inkedGal and (1→3,6)-inked Man along the main chain, in the ratio of 2.0: 1.02: 1.09: 1.10: 0.98. Data showed that SFWP (100, 200 and 400mg/kg) significantly reduced the number of writhings induced by acetic acid in a dose-dependent manner. However, SFWP did not produce analgesia in tail-flick test. Moreover SFWP strongly attenuated the formalin-induced flinching behaviour in the second phases but not in the first phase in a dose-dependent manner. These results revealed that SFWP could be used safely to attenuate both inflammatory and peripheral neuropathic pain. Copyright © 2016 Elsevier B.V. All rights reserved.

SU-F-T-378: Evaluation of Dose-Volume Variability and Parameters Between Prostate IMRT and VMAT Plans

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

Chow, J; Jiang, R; Kiciak, A

2016-06-15

Purpose: This study compared the rectal dose-volume consistency, equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) in prostate intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Methods: For forty prostate IMRT and fifty VMAT patients treated using the same dose prescription (78 Gy/39 fraction) and dose-volume criteria in inverse planning optimization, the rectal EUD and NTCP were calculated for each patient. The rectal dose-volume consistency, showing the variability of dose-volume histogram (DVH) among patients, was defined and calculated based on the deviation between the mean and corresponding rectal DVH. Results: From both the prostate IMRT andmore » VMAT plans, the rectal EUD and NTCP were found decreasing with the rectal volume. The decrease rates for the IMRT plans (EUD = 0.47 × 10{sup −3} Gy cm{sup −3} and NTCP = 3.94 × 10{sup −2} % cm{sup −3}) were higher than those for the VMAT (EUD = 0.28 × 10{sup −3} Gy cm{sup −3} and NTCP = 2.61 × 10{sup −2} % cm{sup −3}). In addition, the dependences of the rectal EUD and NTCP on the dose-volume consistency were found very similar between the prostate IMRT and VMAT plans. This shows that both delivery techniques have similar variations of the rectal EUD and NTCP on the dose-volume consistency. Conclusion: Dependences of the dose-volume consistency on the rectal EUD and NTCP were compared between the prostate IMRT and VMAT plans. It is concluded that both rectal EUD and NTCP decreased with an increase of the rectal volume. The variation rates of the rectal EUD and NTCP on the rectal volume were higher for the IMRT plans than VMAT. However, variations of the rectal dose-volume consistency on the rectal EUD and NTCP were found not significant for both delivery techniques.« less

Interdependence of Platelet-Derived Growth Factor and Estrogen-Signaling Pathways in Inducing Neonatal Rat Testicular Gonocytes Proliferation1

PubMed Central

Thuillier, Raphael; Mazer, Monty; Manku, Gurpreet; Boisvert, Annie; Wang, Yan; Culty, Martine

2010-01-01

We previously found that platelet-derived growth factor (PDGF) and 17beta-estradiol stimulate gonocyte proliferation in a dose-dependent, nonadditive manner. In the present study, we report that gonocytes express RAF1, MAP2K1, and MAPK1/3. Inhibition of RAF1 and MAP2K1/2, but not phosphoinositide-3-kinase, blocked PDGF-induced proliferation. AG-370, an inhibitor of PDGF receptor kinase activity, suppressed not only PDGF-induced proliferation but also that induced by 17beta-estradiol. In addition, RAF1 and MAP2K1/2 inhibitors blocked 17beta-estradiol-activated proliferation. The estrogen receptor antagonist ICI 182780 inhibited both the effects of 17beta-estradiol and PDGF. PDGF lost its stimulatory effect when steroid-depleted serum or no serum was used. Similarly, 17beta-estradiol did not induce gonocyte proliferation in the absence of PDGF. The xenoestrogens genistein, bisphenol A, and DES, but not coumestrol, stimulated gonocyte proliferation in a dose-dependent and PDGF-dependent manner similarly to 17beta-estradiol. Their effects were blocked by ICI 182780, suggesting that they act via the estrogen receptor. AG-370 blocked genistein and bisphenol A effects, demonstrating their requirement of PDGF receptor activation in a manner similar to 17beta-estradiol. These results demonstrate the interdependence of PDGF and estrogen pathways in stimulating in vitro gonocyte proliferation, suggesting that this critical step in gonocyte development might be regulated in vivo by the coordinated action of PDGF and estrogen. Thus, the inappropriate exposure of gonocytes to xenoestrogens might disrupt the crosstalk between the two pathways and potentially interfere with gonocyte development. PMID:20089883

Evaluating antithrombotic activity of HY023016 on rat hypercoagulable model.

PubMed

Chen, Qiu-Fang; Li, Yun-Zhan; Wang, Xin-Hui; Su, You-Rui; Cui, Shuang; Miao, Ming-Xing; Jiang, Zhen-Zhou; Jiang, Mei-Ling; Jiang, Ai-Dou; Chen, Xiang; Xu, Yun-Gen; Gong, Guo-Qing

2016-06-15

The generation of thrombus is not considered as an isolated progression without other pathologic processes, which may also enhance procoagulant state. The purpose of this study was to assess whether HY023016, a novel dabigatran prodrug and an oral direct thrombin inhibitor, or dabigatran etexilate, another thrombin inhibitor can improve the state of whole blood hypercoagulability in vitro/vivo. By using whole blood flow cytometry we explored the effects of HY023016 and dabigatran etexilate on thrombin and ADP-induced human platelet-leukocyte aggregation generated in vitro. With the method of continuous infusion of thrombin intravenous, we successfully established a rat hypercoagulable model and evaluated the effect of HY023016 or dabigatran etexilate in vivo. HY023016 was able to inhibit thrombin- or ADP-induced platelet P-selectin or CD40L expression, leukocyte CD11b expression and formation of platelet-leukocyte aggregates in dose-dependent manner. Dabigatran etexilate was unable to affect ADP-induced platelet P-selectin or CD40L expression, leukocyte CD11b expression and formation of platelet-leukocyte aggregates. Based on rat hypercoagulable model, dabigatran etexilate could reverse thrombin-induced circulatory system hypercoagulable state in a concentration-dependent manner. Dabigatran etexilate also inhibited electrical stimulation induced formation of arterial thrombus in rat under hypercoagulable state, and extracorporal circulation-induced formation of thrombus in dose-dependent manner. Compared with dabigatran etexilate, HY023016 showed nearly equal or even better antithrombotic activity, regardless of reversing the cycle of rat hypercoagulable state or inhibiting platelet-leukocyte aggregation. In surrmary, HY023016 could effectively improve hypercoagulable state of circulatory system. Copyright © 2016. Published by Elsevier B.V.

Antimalarial Activity of Orally Administered Curcumin Incorporated in Eudragit®-Containing Liposomes.

PubMed

Martí Coma-Cros, Elisabet; Biosca, Arnau; Lantero, Elena; Manca, Maria Letizia; Caddeo, Carla; Gutiérrez, Lucía; Ramírez, Miriam; Borgheti-Cardoso, Livia Neves; Manconi, Maria; Fernàndez-Busquets, Xavier

2018-05-04

Curcumin is an antimalarial compound easy to obtain and inexpensive, having shown little toxicity across a diverse population. However, the clinical use of this interesting polyphenol has been hampered by its poor oral absorption, extremely low aqueous solubility and rapid metabolism. In this study, we have used the anionic copolymer Eudragit ® S100 to assemble liposomes incorporating curcumin and containing either hyaluronan (Eudragit-hyaluronan liposomes) or the water-soluble dextrin Nutriose ® FM06 (Eudragit-nutriosomes). Upon oral administration of the rehydrated freeze-dried nanosystems administered at 25/75 mg curcumin·kg −1 ·day −1 , only Eudragit-nutriosomes improved the in vivo antimalarial activity of curcumin in a dose-dependent manner, by enhancing the survival of all Plasmodium yoelii -infected mice up to 11/11 days, as compared to 6/7 days upon administration of an equal dose of the free compound. On the other hand, animals treated with curcumin incorporated in Eudragit-hyaluronan liposomes did not live longer than the controls, a result consistent with the lower stability of this formulation after reconstitution. Polymer-lipid nanovesicles hold promise for their development into systems for the oral delivery of curcumin-based antimalarial therapies.

Tissue accumulation and urinary excretion of Cr in chromium picolinate (CrPic)-supplemented lambs.

PubMed

Dallago, Bruno Stéfano Lima; Lima, Bárbara Alcântara Ferreira; Braz, Shélida Vasconcelos; Mustafa, Vanessa da Silva; McManus, Concepta; Paim, Tiago do Prado; Campeche, Aline; Gomes, Edgard Franco; Louvandini, Helder

2016-05-01

Chromium (Cr) concentrations in liver, kidney, spleen, heart, lymph node, skeletal muscle, bone, testis and urine of lambs were measured to trace the biodistribution and bioaccumulation of Cr after oral supplementation with chromium picolinate (CrPic). Twenty-four Santa Inês lambs were treated with four different concentrations of CrPic: placebo, 0.250, 0.375 and 0.500 mg of CrPic/animal/day for 84 days. The basal diet consisted of Panicum maximum cv Massai hay and concentrate. Cr concentrations were measured by ICP-MS measuring (52)Cr as collected mass. There was a positive linear relationship between dose administered and the accumulation of Cr in the heart, lungs and testis. Urinary excretion of Cr occurred in a time and dose-dependent manner, so the longer or more dietary Cr provided, the greater excretion of the element. As some non-carcass components (such as lungs or heart) are added to bone and visceral meal to feed animals, there is a risk of bioaccumulation and biomagnification due to Cr offered as CrPic in the diet. Copyright © 2016 Elsevier GmbH. All rights reserved.

Effect of noni (Morinda citrifolia Linn.) fruit and its bioactive principles scopoletin and rutin on rat vas deferens contractility: an ex vivo study.

PubMed

Pandy, Vijayapandi; Narasingam, Megala; Kunasegaran, Thubasni; Murugan, Dharmani Devi; Mohamed, Zahurin

2014-01-01

This study examined the effect of methanolic extract of Morinda citrifolia Linn. (MMC) and its bioactive principles, scopoletin and rutin, on dopamine- and noradrenaline-evoked contractility in isolated rat vas deferens preparations. MMC (1-40 mg/mL), scopoletin (1-200 μg/mL), and rutin hydrate (0.6-312.6 μg/mL) dose-dependently inhibited the contractility evoked by submaximal concentrations of both dopamine and noradrenaline, respectively. Haloperidol and prazosin, reference dopamine D2, and α 1-adrenoceptors antagonists significantly reversed the dopamine- and noradrenaline-induced contractions, respectively, in a dose-dependent manner. Interestingly, MMC per se at higher doses (60-100 mg/mL) showed dose-dependent contractile response in rat vas deferens which was partially inhibited by high doses of haloperidol but not by prazosin. These results demonstrated the biphasic effects of MMC on dopaminergic system; that is, antidopaminergic effect at lower concentrations (<40 mg/mL) and dopaminergic agonistic effect at higher concentrations (>60 mg/mL). However, similar contractile response at high doses of scopoletin (0.5-5 mg/mL) and rutin hydrate (0.5-5 mg/mL) per se was not observed. Therefore, it can be concluded that the bioactive principles of MMC, scopoletin, and rutin might be responsible for the antidopaminergic and antiadrenergic activities of MMC.

Cardiovascular changes in atherosclerotic ApoE-deficient mice exposed to Co60 (γ) radiation.

PubMed

Kumarathasan, Prem; Vincent, Renaud; Blais, Erica; Saravanamuthu, Anu; Gupta, Pallavi; Wyatt, Heather; Mitchel, Ronald; Hannan, Mohammed; Trivedi, Akilesh; Whitman, Stewart

2013-01-01

There is evidence for a role of ionizing radiation in cardiovascular diseases. The goal of this work was to identify changes in oxidative and nitrative stress pathways and the status of the endothelinergic system during progression of atherosclerosis in ApoE-deficient mice after single and repeated exposure to ionizing radiation. B6.129P2-ApoE tmlUnc mice on a low-fat diet were acutely exposed (whole body) to Co60 (γ) (single dose 0, 0.5, and 2 Gy) at a dose rate of 36.32 cGy/min, or repeatedly (cumulative dose 0 and 2 Gy) at a dose-rate of 0.1 cGy/min for 5 d/wk, over a period of 4 weeks. Biological endpoints were investigated after 3-6 months of recovery post-radiation. The nitrative stress marker 3-nitrotyrosine and the vasoregulator peptides endothelin-1 and endothelin-3 in plasma were increased (p<0.05) in a dose-dependent manner 3-6 months after acute or chronic exposure to radiation. The oxidative stress marker 8-isoprostane was not affected by radiation, while plasma 8-hydroxydeoxyguanosine and L-3,4-dihydroxyphenylalanine decreased (p<0.05) after treatment. At 2Gy radiation dose, serum cholesterol was increased (p = 0.008) relative to controls. Percent lesion area increased (p = 0.005) with age of animal, but not with radiation treatment. Our observations are consistent with persistent nitrative stress and activation of the endothelinergic system in ApoE-/- mice after low-level ionizing radiation exposures. These mechanisms are known factors in the progression of atherosclerosis and other cardiovascular diseases.

Dose-dependent cytotoxicity evaluation of graphite nanoparticles for diamond-like carbon film application on artificial joints.

PubMed

Liao, T T; Deng, Q Y; Wu, B J; Li, S S; Li, X; Wu, J; Leng, Y X; Guo, Y B; Huang, N

2017-01-24

While a diamond-like carbon (DLC)-coated joint prosthesis represents the implant of choice for total hip replacement in patients, it also leads to concern due to the cytotoxicity of wear debris in the form of graphite nanoparticles (GNs), ultimately limiting its clinical use. In this study, the cytotoxicity of various GN doses was evaluated. Mouse macrophages and osteoblasts were incubated with GNs (<30 nm diameter), followed by evaluation of cytotoxicity by means of assessing inflammatory cytokines, results of alkaline phosphatase assays, and related signaling protein expression. Cytotoxicity evaluation showed that cell viability decreased in a dose-dependent manner (10-100 μg ml -1 ), and steeply declined at GNs concentrations greater than 30 μg ml -1 . Noticeable cytotoxicity was observed as the GN dose exceeded this threshold due to upregulated receptor of activator of nuclear factor kB-ligand expression and downregulated osteoprotegerin expression. Meanwhile, activated macrophage morphology was observed as a result of the intense inflammatory response caused by the high doses of GNs (>30 μg ml -1 ), as observed by the increased release of TNF-α and IL-6. The results suggest that GNs had a significant dose-dependent cytotoxicity in vitro, with a lethal dose of 30 μg ml -1 leading to dramatic increases in cytotoxicity. Our GN cytotoxicity evaluation indicates a safe level for wear debris-related arthropathy and could propel the clinical application of DLC-coated total hip prostheses.

Mechanism of Mitochondrial Transcription Factor A Attenuation of CpG-Induced Antibody Production

PubMed Central

Saifee, Jessica F.; Torres, Raul M.; Janoff, Edward N.

2016-01-01

Mitochondrial transcription factor A (TFAM) had previously been shown to act as a damage associated molecular pattern with the ability to enhance CpG-A phosphorothioate oligodeoxynucleotide (ODN)-mediated stimulation of IFNα production from human plasmacytoid dendritic cells. Examination of the mechanism by which TFAM might influence CpG ODN mediated innate immune responses revealed that TFAM binds directly, tightly and selectively to the structurally related CpG-A, -B, and -C ODN. TFAM also modulated the ability of the CpG-B or -C to stimulate the production of antibodies from human B cells. TFAM showed a dose-dependent modulation of CpG-B, and -C -induced antibody production from human B cells in vitro, with enhancement of high dose and inhibition of low doses of CpG stimulation. This effect was linked to the ability of TFAM to directly inhibit the binding of CpG ODNs to B cells, in a manner consistent with the relative binding affinities of TFAM for the ODNs. These data suggest that TFAM alters the free concentration of the CpG available to stimulate B cells by sequestering this ODN in a TFAM-CpG complex. Thus, TFAM has the potential to decrease the pathogenic consequences of exposure to natural CpG-like hypomethylated DNA in vivo, as well as such as that found in traumatic injury, infection, autoimmune disease and during pregnancy. PMID:27280778

Antitumor Effects of Flavopiridol on Human Uterine Leiomyoma In Vitro and in a Xenograft Model

PubMed Central

Lee, Hyun-Gyo; Baek, Jong-Woo; Shin, So-Jin; Kwon, Sang-Hoon; Cha, Soon-Do; Park, Won-Jin; Chung, Rosa; Choi, Eun-Som; Lee, Gun-Ho

2014-01-01

Dysregulated cyclin-dependent kinases (CDKs) are considered a potential target for cancer therapy. Flavopiridol is a potent CDK inhibitor. In this study, the antiproliferative effect of the flavonoid compound flavopiridol and its mechanism in human uterine leiomyoma cells were investigated. The present study focused on the effect of flavopiridol in cell proliferation and cell cycle progression in primary cultured human uterine leiomyoma cells. Cell viability and cell proliferation assays were conducted. Flow cytometry was performed to determine the effect of flavopiridol on cell cycle. The expression of cell cycle regulatory-related proteins was evaluated by Western blotting. Cell viability and proliferation of uterine leiomyoma cells were significantly reduced by flavopiridol treatment in a dose-dependent manner. Flow cytometry results showed that flavopiridol induced G1 phase arrest. Flavopiridol-induced growth inhibition in uterine leiomyoma cells was associated with increased expression of p21cip/wafl and p27kip1 in a dose-dependent manner. Downregulation of CDK2/4 and Cyclin A with a concomitant increase in dephosphorylation of retinoblastoma was observed. This study demonstrates that flavopiridol inhibits cell proliferation by initiating G1 cell cycle arrest in human uterine leiomyoma. We also found that flavopiridol is effective in inhibiting xenografted human uterine leiomyoma growth. These results indicate that flavopiridol could prove to be a promising chemopreventive and therapeutic agent for human uterine leiomyoma. PMID:24572052

1,8-cineole inhibits both proliferation and elongation of BY-2 cultured tobacco cells.

PubMed

Yoshimura, Hiroko; Sawai, Yu; Tamotsu, Satoshi; Sakai, Atsushi

2011-03-01

Volatile monoterpenes such as 1,8-cineole inhibit the growth of Brassica campestris seedlings in a dose-dependent manner, and the growth-inhibitory effects are more severe for roots than hypocotyls. The preferential inhibition of root growth may be explained if the compounds inhibit cell proliferation more severely than cell elongation because root growth requires both elongation and proliferation of the constituent cells, whereas hypocotyl growth depends exclusively on elongation of existing cells. In order to examine this possibility, BY-2 suspension-cultured tobacco (Nicotiana tabacum) cells were treated with 1,8-cineole, and the inhibitory effects on cell proliferation and on cell elongation were assessed quantitatively. Treatment with 1,8-cineole lowered both the mitotic index and elongation of the cells in a dose-dependent manner, and the half-maximal inhibitory concentration (IC₅₀) for cell elongation was lower than that for cell proliferation. Moreover, 1,8-cineole also inhibited starch synthesis, with IC₅₀ lower than that for cell proliferation. Thus, the inhibitory effects of 1,8-cineole were not specific to cell proliferation; rather, 1,8-cineole seemed inhibitory to a variety of physiological activities when it was in direct contact with target cells. Based on these results, possible mechanisms for the mode of action of 1,8-cineole and for its preferential inhibition on root growth are discussed.

Millimeter wave treatment induces apoptosis via activation of the mitochondrial-dependent pathway in human osteosarcoma cells.

PubMed

Wu, Guangwen; Chen, Xuzheng; Peng, Jun; Cai, Qiaoyan; Ye, Jinxia; Xu, Huifeng; Zheng, Chunsong; Li, Xihai; Ye, Hongzhi; Liu, Xianxiang

2012-05-01

Millimeter wave (MW) is an electromagnetic wave with a wavelength between 1 and 10 mm and a frequency of 30-300 GHz that causes multiple biological effects and has been used as a major component in physiotherapies for the clinical treatment of various types of diseases including cancers. However, the precise molecular mechanism of the anticancer activity of millimeter wave remains to be elucidated. In the present study, we investigated the cellular effects of the MW in the U-2OS human osteosarcoma cell line. Our results showed that MW induced cell morphological changes and reduced cell viability in a dose- and time-dependent manner suggesting that MW inhibited the growth of U-2OS cells as demonstrated. Hoechst 33258 staining and Annexin V/propidium iodide double staining exhibited the typical nuclear features of apoptosis and increased the proportion of apoptotic Annexin V-positive cells in a dose-dependent manner, respectively. In addition, MW treatment caused loss of plasma membrane asymmetry, release of cytochrome c, collapse of mitochondrial membrane potential, activation of caspase-9 and -3, and increase of the ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2. Taken together, the results indicate that the U-2OS cell growth inhibitory activity of MW was due to mitochondrial-mediated apoptosis, which may partly explain the anticancer activity of millimeter wave treatment.

Antioxidant effects of methylprednisolone and hydrocortisone on the impairment of endothelium dependent relaxation induced by reactive oxygen species in rabbit abdominal aorta

PubMed Central

Lee, Hee Jong; Song, Hyun Hoo; Jeong, Mi Ae; Yeom, Jong Hoon; Kim, Dong Won

2013-01-01

Background The reperfusion following ischemia produces reactive oxygen species (ROS). We studied the influences of methylprednisolone (MPD) and hydrocortisone (CRT) on ROS effects using the endothelium of rabbit abdominal aorta. Methods Isolated rabbit aortic rings were suspended in an organ bath filled with Krebs-Henseleit (K-H) solution. After precontraction with norepinephrine, changes in arterial tension were recorded following the cumulative administration of acetylcholine (ACh). The percentages of ACh-induced relaxation of aortic rings before and after exposure to ROS, generated by electrolysis of K-H solution, were used as the control and experimental values, respectively. The aortic rings were pretreated with MPD or CRT at the same concentrations, and the effects of these agents were compared with the effects of ROS scavenger inhibitors: superoxide dismutase inhibitor, diethylthiocarbamate (DETCA), and the catalase inhibitor, 3-amino-1,2,4-triazole (3AT). Results Both MPD and CRT maintained endothelium-dependent relaxation induced by ACh in a dose-related manner in spite of ROS attack. The restored ACh-induced relaxation of MPD and CRT group was not attenuated by pretreatment of 3AT and DETCA. Conclusions MPD and CRT preserve the endothelium-dependent vasorelaxation against the attack of ROS, in a dose-related manner. Endothelial protection mechanisms of MPD and CRT may be not associated with hydrogen peroxide and superoxide scavenging. PMID:23372887

Dose- and Time-Dependent Transcriptional Response of Ishikawa Cells Exposed to Genistein

PubMed Central

Naciff, Jorge M.; Khambatta, Zubin S.; Carr, Gregory J.; Tiesman, Jay P.; Singleton, David W.; Khan, Sohaib A.; Daston, George P.

2016-01-01

To further define the utility of the Ishikawa cells as a reliable in vitro model to determine the potential estrogenic activity of chemicals of interest, transcriptional changes induced by genistein (GES) in Ishikawa cells at various doses (10 pM, 1 nM, 100 nM, and 10 μM) and time points (8, 24, and 48 h) were identified using a comprehensive microarray approach. Trend analysis indicated that the expression of 5342 unique genes was modified by GES in a dose- and time-dependent manner (P ≤ 0.0001). However, the majority of gene expression changes induced in Ishikawa cells were elicited by the highest dose of GES evaluated (10 μM). The GES’ estrogenic activity was identified by comparing the Ishikawa cells’ response to GES versus 17 α-ethynyl estradiol (EE, at equipotent doses, ie, 10 μM vs 1 μM, respectively) and was defined by changes in the expression of 284 unique genes elicited by GES and EE in the same direction, although the magnitude of the change for some genes was different. Further, comparing the response of the Ishikawa cells exposed to high doses of GES and EE versus the response of the juvenile rat uterus exposed to EE, we identified 66 unique genes which were up- or down regulated in a similar manner in vivo as well as in vitro. Genistein elicits changes in multiple molecular pathways affecting various biological processes particularly associated with cell organization and biogenesis, regulation of translation, cell proliferation, and intracellular transport; processes also affected by estrogen exposure in the uterus of the rat. These results indicate that Ishikawa cells are capable of generating a biologically relevant estrogenic response and offer an in vitro model to assess this mode of action. PMID:26865667

Dose- and Time-Dependent Transcriptional Response of Ishikawa Cells Exposed to Genistein.

PubMed

Naciff, Jorge M; Khambatta, Zubin S; Carr, Gregory J; Tiesman, Jay P; Singleton, David W; Khan, Sohaib A; Daston, George P

2016-05-01

To further define the utility of the Ishikawa cells as a reliable in vitro model to determine the potential estrogenic activity of chemicals of interest, transcriptional changes induced by genistein (GES) in Ishikawa cells at various doses (10 pM, 1 nM, 100 nM, and 10 μM) and time points (8, 24, and 48 h) were identified using a comprehensive microarray approach. Trend analysis indicated that the expression of 5342 unique genes was modified by GES in a dose- and time-dependent manner (P ≤ 0.0001). However, the majority of gene expression changes induced in Ishikawa cells were elicited by the highest dose of GES evaluated (10 μM). The GES' estrogenic activity was identified by comparing the Ishikawa cells' response to GES versus 17 α-ethynyl estradiol (EE, at equipotent doses, ie, 10 μM vs 1 μM, respectively) and was defined by changes in the expression of 284 unique genes elicited by GES and EE in the same direction, although the magnitude of the change for some genes was different. Further, comparing the response of the Ishikawa cells exposed to high doses of GES and EE versus the response of the juvenile rat uterus exposed to EE, we identified 66 unique genes which were up- or down regulated in a similar manner in vivo as well as in vitro Genistein elicits changes in multiple molecular pathways affecting various biological processes particularly associated with cell organization and biogenesis, regulation of translation, cell proliferation, and intracellular transport; processes also affected by estrogen exposure in the uterus of the rat. These results indicate that Ishikawa cells are capable of generating a biologically relevant estrogenic response and offer an in vitro model to assess this mode of action. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Early Biochemical Effects of an Organic Mercury Fungicide on Infants: ``Dose Makes the Poison''

NASA Astrophysics Data System (ADS)

Gotelli, Carlos A.; Astolfi, Emilio; Cox, Christopher; Cernichiari, Elsa; Clarkson, Thomas W.

1985-02-01

Phenylmercury absorbed through the skin from contaminated diapers affected urinary excretion in infants in Buenos Aires. The effects were reversible and quantitatively related to the concentration of urinary mercury. Excretion of γ -glutamyl transpeptidase, an enzyme in the brush borders of renal tubular cells, increased in a dose-dependent manner when mercury excretion exceeded a ``threshold'' value. Urine volume also increased but at a higher threshold with respect to mercury. The results support the threshold concept of the systemic toxicity of metals. γ -Glutamyl transpeptidase is a useful and sensitive marker for preclinical effects of toxic metals.

Decreasing effect of an anti-Nfa1 polyclonal antibody on the in vitro cytotoxicity of pathogenic Naegleria fowleri

PubMed Central

Jeong, Seok-Ryoul; Kang, Su-Yeon; Lee, Sang-Chul; Song, Kyoung-Ju; Im, Kyung-il

2004-01-01

The nfa1 gene was cloned from a cDNA library of pathogenic Naegleria fowleri by immunoscreening; it consisted of 360 bp and produced a 13.1 kDa recombinant protein (rNfa1) that showed the pseudopodia-specific localization by immunocytochemistry in the previous study. Based on the idea that the pseudopodia-specific Nfa1 protein mentioned above seems to be involved in the pathogenicity of N. fowleri, we observed the effect of an anti-Nfa1 antibody on the proliferation of N. fowleri trophozoites and the cytotoxicity of N. fowleri trophozoites on the target cells. The proliferation of N. fowleri trophozoites was inhibited after being treated with an anti-Nfa1 polyclonal antibody in a dose-dependent manner for 48 hrs. By a light microscope, CHO cells co-cultured with N. fowleri trophozoites (group I) for 48 hrs showed severe morphological destruction. On the contrary, CHO cells co-cultured with N. fowleri trophozoites and anti-Nfa1 polyclonal antibody (1:100 dilution) (group II) showed less destruction. In the LDH release assay results, group I showed 50.6% cytotoxicity, and group II showed 39.3%. Consequently, addition of an anti-Nfa1 polyclonal antibody produced a decreasing effect of in vitro cytotoxicity of N. fowleri in a dosedependent manner. PMID:15060338

The Macrocyclic Peptide Natural Product CJ-15,208 is Orally Active and Prevents Reinstatement of Extinguished Cocaine Seeking Behavior1

PubMed Central

Aldrich, Jane V.; Senadheera, Sanjeewa N.; Ross, Nicolette C.; Ganno, Michelle L.; Eans, Shainnel O.; McLaughlin, Jay P.

2013-01-01

The macrocyclic tetrapeptide natural product CJ-15,208 (cyclo[Phe-D-Pro-Phe-Trp]) exhibited both dose-dependent antinociception and kappa opioid receptor (KOR) antagonist activity after oral administration. CJ-15,208 antagonized a centrally administered KOR selective agonist, providing strong evidence it crosses the blood-brain barrier to reach KOR in the CNS. Orally administered CJ-15,208 also prevented both cocaine- and stress-induced reinstatement of extinguished cocaine seeking behavior in the conditioned place preference assay in a time- and dose-dependent manner. Thus, CJ-15,208 is a promising lead compound with a unique activity profile for potential development, particularly as a therapeutic to prevent relapse to drug seeking behavior in abstinent subjects. PMID:23327691

The action of ryanodine on rat fast and slow intact skeletal muscles.

PubMed

Fryer, M W; Lamb, G D; Neering, I R

1989-07-01

1. The action of ryanodine on force development of bundles dissected from rat extensor digitorum longus (EDL) and soleus muscles has been examined. 2. Ryanodine (100-5000 nM) irreversibly depressed twitch and tetanic tension of both muscle types in a dose-related manner. 3. At concentrations above 250 nM, ryanodine induced a slowly developing, dose-dependent contracture which could not be blocked by 5 mM-Co2+. Increasing the stimulation rate or decreasing the oxygenation of the preparation accelerated the rate of contracture development while the total removal of extracellular Ca2+ was required to prevent it. 4. Following the relaxation of the initial contracture (IC) in Ca2+-free solution, a second type of contracture (SC) could be induced by the readdition of Ca2+. This contracture differed from IC in that it was dependent on Ca2+ in the millimolar range and was prevented by 5 mM-Co2+. Both IC and SC were relaxed by perfusion with Ca2+-free, EGTA-containing solution. 5. Subcontracture doses of ryanodine (100 nM) markedly potentiated caffeine contractures of both muscle types. 6. Asymmetric charge movement in EDL fibres was recorded with the Vaseline-gap technique. The amount of charge moved near threshold was virtually unaffected by the presence of 10 microM-ryanodine over the time examined. 7. The results are consistent with the suggestion that ryanodine locks the calcium release channels of the sarcoplasmic reticulum (SR) in an open subconductance state with reduced conductance. It appears that lowering the external calcium concentration might still inactivate the release channels after they have been blocked open by ryanodine, possibly by an effect on the T-tubular voltage sensor.

Analgesic Effects of Duloxetine on Formalin-Induced Hyperalgesia and Its Underlying Mechanisms in the CeA

PubMed Central

Zhang, Lie; Yin, Jun-Bin; Hu, Wei; Zhao, Wen-Jun; Fan, Qing-Rong; Qiu, Zhi-Chun; He, Ming-Jie; Ding, Tan; Sun, Yan; Kaye, Alan D.; Wang, En-Ren

2018-01-01

In rodents, the amygdala has been proposed to serve as a key center for the nociceptive perception. Previous studies have shown that extracellular signal-regulated kinase (ERK) signaling cascade in the central nucleus of amygdala (CeA) played a functional role in inflammation-induced peripheral hypersensitivity. Duloxetine (DUL), a serotonin and noradrenaline reuptake inhibitor, produced analgesia on formalin-induced spontaneous pain behaviors. However, it is still unclear whether single DUL pretreatment influences formalin-induced hypersensitivity and what is the underlying mechanism. In the current study, we revealed that systemic pretreatment with DUL not only dose-dependently suppressed the spontaneous pain behaviors, but also relieved mechanical and thermal hypersensitivity induced by formalin hindpaw injection. Consistent with the analgesic effects of DUL on the pain behaviors, the expressions of Fos and pERK that were used to check the neuronal activities in the spinal cord and CeA were also dose-dependently reduced following DUL pretreatment. Meanwhile, no emotional aversive behaviors were observed at 24 h after formalin injection. The concentration of 5-HT in the CeA was correlated with the dose of DUL in a positive manner at 24 h after formalin injection. Direct injecting 5-HT into the CeA suppressed both the spontaneous pain behaviors and hyperalgesia induced by formalin injection. However, DUL did not have protective effects on the formalin-induced edema of hindpaw. In sum, the activation of CeA neurons may account for the transition from acute pain to long-term hyperalgesia after formalin injection. DUL may produce potent analgesic effects on the hyperalgesia and decrease the expressions of p-ERK through increasing the concentration of serotonin in the CeA. PMID:29692727

Analgesic Effects of Duloxetine on Formalin-Induced Hyperalgesia and Its Underlying Mechanisms in the CeA.

PubMed

Zhang, Lie; Yin, Jun-Bin; Hu, Wei; Zhao, Wen-Jun; Fan, Qing-Rong; Qiu, Zhi-Chun; He, Ming-Jie; Ding, Tan; Sun, Yan; Kaye, Alan D; Wang, En-Ren

2018-01-01

In rodents, the amygdala has been proposed to serve as a key center for the nociceptive perception. Previous studies have shown that extracellular signal-regulated kinase (ERK) signaling cascade in the central nucleus of amygdala (CeA) played a functional role in inflammation-induced peripheral hypersensitivity. Duloxetine (DUL), a serotonin and noradrenaline reuptake inhibitor, produced analgesia on formalin-induced spontaneous pain behaviors. However, it is still unclear whether single DUL pretreatment influences formalin-induced hypersensitivity and what is the underlying mechanism. In the current study, we revealed that systemic pretreatment with DUL not only dose-dependently suppressed the spontaneous pain behaviors, but also relieved mechanical and thermal hypersensitivity induced by formalin hindpaw injection. Consistent with the analgesic effects of DUL on the pain behaviors, the expressions of Fos and pERK that were used to check the neuronal activities in the spinal cord and CeA were also dose-dependently reduced following DUL pretreatment. Meanwhile, no emotional aversive behaviors were observed at 24 h after formalin injection. The concentration of 5-HT in the CeA was correlated with the dose of DUL in a positive manner at 24 h after formalin injection. Direct injecting 5-HT into the CeA suppressed both the spontaneous pain behaviors and hyperalgesia induced by formalin injection. However, DUL did not have protective effects on the formalin-induced edema of hindpaw. In sum, the activation of CeA neurons may account for the transition from acute pain to long-term hyperalgesia after formalin injection. DUL may produce potent analgesic effects on the hyperalgesia and decrease the expressions of p-ERK through increasing the concentration of serotonin in the CeA.

Illicit use of LSD or psilocybin, but not MDMA or nonpsychedelic drugs, is associated with mystical experiences in a dose-dependent manner.

PubMed

Lyvers, Michael; Meester, Molly

2012-01-01

Psychedelic drugs have long been known to be capable of inducing mystical or transcendental experiences. However, given the common "recreational" nature of much present-day psychedelic use, with typical doses tending to be lower than those commonly taken in the 1960s, the extent to which illicit use of psychedelics today is associated with mystical experiences is not known. Furthermore the mild psychedelic MDMA ("Ecstasy") is more popular today than "full" psychedelics such as LSD or psilocybin, and the contribution of illicit MDMA use to mystical experiences is not known. The present study recruited 337 adults from the website and newsletter of the Multidisciplinary Association for Psychedelic Studies (MAPS), most of whom reported use of a variety of drugs both licit and illicit including psychedelics. Although only a quarter of the sample reported "spiritual" motives for using psychedelics, use of LSD and psilocybin was significantly positively related to scores on two well-known indices of mystical experiences in a dose-related manner, whereas use of MDMA, cannabis, cocaine, opiates and alcohol was not. Results suggest that even in today's context of "recreational" drug use, psychedelics such as LSD and psilocybin, when taken at higher doses, continue to induce mystical experiences in many users.

Dose-Related Modulation of Event-Related Potentials to Novel and Target Stimuli by Intravenous Δ9-THC in Humans

PubMed Central

D'Souza, Deepak Cyril; Fridberg, Daniel J; Skosnik, Patrick D; Williams, Ashley; Roach, Brian; Singh, Nagendra; Carbuto, Michelle; Elander, Jacqueline; Schnakenberg, Ashley; Pittman, Brian; Sewell, R Andrew; Ranganathan, Mohini; Mathalon, Daniel

2012-01-01

Cannabinoids induce a host of perceptual alterations and cognitive deficits in humans. However, the neural correlates of these deficits have remained elusive. The current study examined the acute, dose-related effects of delta-9-tetrahydrocannabinol (Δ9-THC) on psychophysiological indices of information processing in humans. Healthy subjects (n=26) completed three test days during which they received intravenous Δ9-THC (placebo, 0.015 and 0.03 mg/kg) in a within-subject, double-blind, randomized, cross-over, and counterbalanced design. Psychophysiological data (electroencephalography) were collected before and after drug administration while subjects engaged in an event-related potential (ERP) task known to be a valid index of attention and cognition (a three-stimulus auditory ‘oddball' P300 task). Δ9-THC dose-dependently reduced the amplitude of both the target P300b and the novelty P300a. Δ9-THC did not have any effect on the latency of either the P300a or P300b, or on early sensory-evoked ERP components preceding the P300 (the N100). Concomitantly, Δ9-THC induced psychotomimetic effects, perceptual alterations, and subjective ‘high' in a dose-dependent manner. Δ9-THC -induced reductions in P3b amplitude correlated with Δ9-THC-induced perceptual alterations. Lastly, exploratory analyses examining cannabis use status showed that whereas recent cannabis users had blunted behavioral effects to Δ9-THC, there were no dose-related effects of Δ9-THC on P300a/b amplitude between cannabis-free and recent cannabis users. Overall, these data suggest that at doses that produce behavioral and subjective effects consistent with the known properties of cannabis, Δ9-THC reduced P300a and P300b amplitudes without altering the latency of these ERPs. Cannabinoid agonists may therefore disrupt cortical processes responsible for context updating and the automatic orientation of attention, while leaving processing speed and earlier sensory ERP components intact. Collectively, the findings suggest that CB1R systems modulate top-down and bottom-up processing. PMID:22334121

Intra-oral administration of rebamipide liquid prevents tongue injuries induced by X-ray irradiation in rats.

PubMed

Nakashima, Takako; Uematsu, Naoya; Sakurai, Kazushi

2017-07-01

Oral mucositis is a common and serious side effect in patients who undergo cytotoxic cancer therapies. The purpose of this study was to investigate the preventive effects of rebamipide on radiation-induced glossitis model in rats. Glossitis was induced by a single dose of 15 Gy of X-rays to the snouts of rats (day 0). A novel form of rebamipide liquid comprising its submicronized crystals was administered intra-orally. The preventive effect of rebamipide on tongue injuries was macroscopically evaluated on day 7 following irradiation. The pretreatment period, dosing frequency, and dose dependency of rebamipide were examined. Two percent rebamipide liquid, administered six times a day for 14 days from day -7 to day 6, significantly decreased the ulcer-like area. However, no significant effect was observed when rebamipide was given either from day -4 or from day -1. Four or six times daily, 2% rebamipide liquid significantly inhibited the ulcer-like injury area ratio, but not when given twice daily. Rebamipide liquid, 1, 2, and 4% six times daily significantly reduced the area ratios of total injury and ulcer-like injury in a dose-dependent manner. Gene expression and protein levels of proinflammatory cytokines and chemokines were dramatically elevated in the irradiated tongues of control rats on day 7 without rebamipide liquid treatment. They were dose-dependently and significantly suppressed in rebamipide-treated groups. Intra-oral administration of rebamipide liquid prevented oral mucositis dose-dependently accompanied by the suppression of inflammatory expression in the radiation-induced rats' glossitis model.

CB1 receptor-mediated signaling underlies the hippocampal synaptic, learning, and memory deficits following treatment with JWH-081, a new component of spice/K2 preparations.

PubMed

Basavarajappa, Balapal S; Subbanna, Shivakumar

2014-02-01

Recently, synthetic cannabinoids have been sprayed onto plant material, which is subsequently packaged and sold as "Spice" or "K2" to mimic the effects of marijuana. A recent report identified several synthetic additives in samples of "Spice/K2", including JWH-081, a synthetic ligand for the cannabinoid receptor 1 (CB1). The deleterious effects of JWH-081 on brain function are not known, particularly on CB1 signaling, synaptic plasticity, learning and memory. Here, we evaluated the effects of JWH-081 on pCaMKIV, pCREB, and pERK1/2 signaling events followed by long-term potentiation (LTP), hippocampal-dependent learning and memory tasks using CB1 receptor wild-type (WT) and knockout (KO) mice. Acute administration of JWH-081 impaired CaMKIV phosphorylation in a dose-dependent manner, whereas inhibition of CREB phosphorylation in CB1 receptor WT mice was observed only at higher dose of JWH-081 (1.25 mg/kg). JWH-081 at higher dose impaired CaMKIV and CREB phosphorylation in a time-dependent manner in CB1 receptor WT mice but not in KO mice and failed to alter ERK1/2 phosphorylation. In addition, SR treated or CB1 receptor KO mice have a lower pCaMKIV/CaMKIV ratio and higher pCREB/CREB ratio compared with vehicle or WT littermates. In hippocampal slices, JWH-081 impaired LTP in CB1 receptor WT but not in KO littermates. Furthermore, JWH-081 at higher dose impaired object recognition, spontaneous alternation and spatial memory on the Y-maze in CB1 receptor WT mice but not in KO mice. Collectively our findings suggest that deleterious effects of JWH-081 on hippocampal function involves CB1 receptor mediated impairments in CaMKIV and CREB phosphorylation, LTP, learning and memory in mice. © 2013 Wiley Periodicals, Inc.

Cross-talk between interferon-gamma and interleukin-18 in melanogenesis.

PubMed

Zhou, Jia; Ling, Jingjing; Wang, Yong; Shang, Jing; Ping, Fengfeng

2016-10-01

Skin is the largest organ in our body and strategically placed to provide a metabolically active biological barrier against a range of noxious stressors. A lot of inflammatory cytokines, which are increased after ultraviolet (UV) irradiation produced by keratinocytes or other immunocytes, are closely related to pigmentary changes, including interleukin-18 (IL-18) and interferon-γ (IFN-γ). In this study, the effect of cross-talk between IL-18 and IFN-γ on melanogenesis was investigated. Treatment with IL-18 resulted in a dose-dependent increase of melanogenesis, while IFN-γ made an opposite effect. This influence of IL-18 and IFN-γ was mediated by regulations of microphthalmia-associated transcription factor (MITF) and its downstream enzymatic cascade expressions. Furthermore, IFN-γ inhibited basal and IL-18-induced melanogenesis. IFN-γ increased signal transducer and activator of transcription-1 (STAT-1) phosphorylation to play its position in regulating melanin pigmentation, and its inhibitory effect could be prevented by Janus Kinase 1 (JAK 1) inhibitor. IFN-γ could inhibit melanogenesis by decreasing melanocyte dendrite formation. In addition, IFN-γ inhibited the expressions of Rab Pases to suppress the mature and transport of melanosomes. IL-18 could rapidly induce Akt and PTEN phosphorylation and p65 expression in B16F10 cells. When treatment with IL-18 and IFN-γ together, the phosphorylation level of Protein Kinase B (Akt) and phosphatase and tensin homolog deleted on chromosome ten (PTEN) and expression of p65 NF-κB were inhibited, compared with treated with IL-18 only. Our studies indicated that IFN-γ could directly induce B16F10 cells apoptosis in vitro. Furthermore, we demonstrated that IFN-γ markedly up-regulated IL-18 binding protein (BP) production in normal human foreskin-derived epidermal keratinocytes in dose-dependent manner. UVB irradiation induced protease-activated receptor-2 (PAR-2) expression in NHEK, IFN-γ could inhibit this enhancement in a dose-dependent manner. These data suggest that IFN-γ plays a role in regulating inflammation- or UV-induced pigmentary changes, in direct/indirect manner. Copyright © 2016 Elsevier B.V. All rights reserved.

Spermidine promotes stress resistance in Drosophila melanogaster through autophagy-dependent and -independent pathways.

PubMed

Minois, N; Carmona-Gutierrez, D; Bauer, M A; Rockenfeller, P; Eisenberg, T; Brandhorst, S; Sigrist, S J; Kroemer, G; Madeo, F

2012-10-11

The naturally occurring polyamine spermidine (Spd) has recently been shown to promote longevity across species in an autophagy-dependent manner. Here, we demonstrate that Spd improves both survival and locomotor activity of the fruit fly Drosophila melanogaster upon exposure to the superoxide generator and neurotoxic agent paraquat. Although survival to a high paraquat concentration (20 mM) was specifically increased in female flies only, locomotor activity and survival could be rescued in both male and female animals when exposed to lower paraquat levels (5 mM). These effects are dependent on the autophagic machinery, as Spd failed to confer resistance to paraquat-induced toxicity and locomotor impairment in flies deleted for the essential autophagic regulator ATG7 (autophagy-related gene 7). Spd treatment did also protect against mild doses of another oxidative stressor, hydrogen peroxide, but in this case in an autophagy-independent manner. Altogether, this study establishes that the protective effects of Spd can be exerted through different pathways that depending on the oxidative stress scenario do or do not involve autophagy.

N-acetylcysteine inhibits induction of nitric oxide synthase in 3T3-L1 adipocytes.

PubMed

Araki, Shunsuke; Dobashi, Kazushige; Kubo, Kazuyasu; Kawagoe, Rinko; Yamamoto, Yukiyo; Shirahata, Akira

2007-12-01

The present study was designed to determine whether N-acetylcysteine (NAC), a potent antioxidant, modulates nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-alpha) in adipocytes. Stimulation by the combination of 5 microg/ml of LPS and 100 ng/ml of TNF-alpha (LT) significantly enhanced NO production in 3T3-L1 adipocytes. Preincubation of the cells with NAC (5-20 mM) for 24 h suppressed the increased NO production in a dose-dependent manner. The production of NO was decreased by 49% at the concentration of 20 mM of NAC. The decrease in NO production by NAC was accompanied by a decrease in inducible nitric oxide synthase (iNOS) protein, detected by immunoblot analysis, and iNOS mRNA, determined by real-time reverse-transcriptase coupled polymerase chain reaction analysis. Nuclear factor-kappa B (NF-kappa B) was significantly activated by LT-treatment, while the pretreatment with 20 mM of NAC prevented the activity by 42%. Pyrrolidine dithiocarbamate (PDTC), a NF-kappaB inhibitor, also inhibited the LT-mediated NO production dose-dependently. One hundred microM of PDTC inhibited the NO production by 46%. We also investigated the effect of NAC and PDTC on the production of interleukein-6 (IL-6), which is regulated transcriptionally by NF-kappa B in 3T3-L1 adipocytes. IL-6 production was markedly increased by LT stimulus, and the enhanced secretion of IL-6 was suppressed in a dose-dependent manner by pretreatment with NAC or PDTC. These results suggest that NAC regulates iNOS expression and NO production in adipocytes through the modulating activation of NF-kappa B.

A meta-analysis of the effects of Lactobacillus buchneri on the fermentation and aerobic stability of corn and grass and small-grain silages.

PubMed

Kleinschmit, D H; Kung, L

2006-10-01

The results of adding Lactobacillus buchneri to silages from 43 experiments in 23 sources reporting standard errors were summarized using meta-analysis. The effects of inoculation were summarized by type of crop (corn or grass and small grains) and the treatments were classified into the following categories: 1) untreated silage with nothing applied (LB0), 2) silage treated with L. buchneri at < or = 100,000 cfu/g of fresh forage (LB1), and 3) silage treated with L. buchneri at > 100,000 cfu/g (LB2). In both types of crops, inoculation with L. buchneri decreased concentrations of lactic acid, and this response was dose-dependent in corn but not in grass and small-grain silages. Treatment with L. buchneri markedly increased the concentrations of acetic acid in both crops in a dose-dependent manner. The numbers of yeasts were lower in silages treated with LB1 and further decreased in silages treated with LB2 compared with untreated silages. Untreated corn silage spoiled after 25 h of exposure to air but corn silage treated with LB1 did not spoil until 35 h, and this stability was further enhanced to 503 h with LB2. In grass and small-grain silages, yeasts were nearly undetectable; however, inoculation improved aerobic stability in a dose-dependent manner (206, 226, and 245 h for LB0, LB1, and LB2, respectively). The recovery of DM after ensiling was lower for LB2 (94.5%) when compared with LB0 (95.5%) in corn silage and was lower for both LB1 (94.8%) and LB2 (95.3%) when compared with LB0 (96.6%) in grass and small-grain silages.

Unexpected T cell regulatory activity of anti-histone H1 autoantibody: Its mode of action in regulatory T cell-dependent and -independent manners

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

Takaoka, Yuki; Kawamoto, Seiji, E-mail: skawa@hiroshima-u.ac.jp; Katayama, Akiko

2013-02-08

Highlights: ► Anti-histone H1 autoantibody (anti-H1) acts on T cells to inhibit their activation. ► Anti-H1 suppresses T cell activation in Treg cell-dependent and -independent manners. ► Suboptimal dose of anti-H1 enhances suppressor function of Treg cells. ► High dose of anti-H1 directly inhibits T cell receptor signaling. -- Abstract: Induction of anti-nuclear antibodies against DNA or histones is a hallmark of autoimmune disorders, but their actual contribution to disease predisposition remains to be clarified. We have previously reported that autoantibodies against histone H1 work as a critical graft survival factor in a rat model of tolerogeneic liver transplantation. Heremore » we show that an immunosuppressive anti-histone H1 monoclonal antibody (anti-H1 mAb) acts directly on T cells to inhibit their activation in response to T cell receptor (TCR) ligation. Intriguingly, the T cell activation inhibitory activity of anti-H1 mAb under suboptimal dosages required regulatory T (Treg) cells, while high dose stimulation with anti-H1 mAb triggered a Treg cell-independent, direct negative regulation of T cell activation upon TCR cross-linking. In the Treg cell-dependent mode of immunosuppressive action, anti-H1 mAb did not induce the expansion of CD4{sup +}Foxp3{sup +} Treg cells, but rather potentiated their regulatory capacity. These results reveal a previously unappreciated T cell regulatory role of anti-H1 autoantibody, whose overproduction is generally thought to be pathogenic in the autoimmune settings.« less

Excess aldosterone-induced changes in insulin signaling molecules and glucose oxidation in gastrocnemius muscle of adult male rat.

PubMed

Selvaraj, Jayaraman; Sathish, Sampath; Mayilvanan, Chinnaiyan; Balasubramanian, Karundevi

2013-01-01

Emerging evidences demonstrate that excess aldosterone and insulin interact at target tissues. It has been shown that increased levels of aldosterone contribute to the development of insulin resistance and thus act as a risk factor for the development of type-2 diabetes mellitus. However, the molecular mechanisms involved in this scenario are yet to be identified. This study was designed to assess the dose-dependent effects of aldosterone on insulin signal transduction and glucose oxidation in the skeletal muscle (gastrocnemius) of adult male rat. Healthy adult male albino rats of Wistar strain (Rattus norvegicus) weighing 180-200 g were used in this study. Rats were divided into four groups. Group I: control (treated with 1 % ethanol only), group II: aldosterone treated (10 μg /kg body weight, twice daily for 15 days), group III: aldosterone treated (20 μg /kg body weight, twice daily for 15 days), and group IV: aldosterone treated (40 μg/kg body weight, twice daily for 15 days). Excess aldosterone caused glucose intolerance in a dose-dependent manner. Serum insulin and aldosterone were significantly increased, whereas serum testosterone was decreased. Aldosterone treatment impaired the rate of glucose uptake, oxidation, and insulin signal transduction in the gastrocnemius muscle through defective expression of IR, IRS-1, Akt, AS160, and GLUT4 genes. Phosphorylation of IRS-1, β-arrestin-2, and Akt was also reduced in a dose-dependent manner. Excess aldosterone results in glucose intolerance as a result of impaired insulin signal transduction leading to decreased glucose uptake and oxidation in skeletal muscle. In addition to this, it is inferred that excess aldosterone may act as one of the causative factors for the onset of insulin resistance and thus increased incidence of type-2 diabetes.

Clinical Usefulness of the Histoculture Drug Response Assay for Prostate Cancer and Benign Prostate Hypertrophy (BPH).

PubMed

Hoffman, Robert M

2018-01-01

The histoculture drug response assay (HDRA) has been adapted to determine androgen sensitivity in Gelfoam histoculture of human benign prostatic tissue as well as prostate cancer. Gelfoam histoculture was used to measure androgen-independent and androgen-dependent growth of benign and malignant prostate tissue. The androgen-sensitivity index was significantly higher in 23 paired specimens of prostate cancer compared to benign prostate hypertrophy (BPH). Genistein decreased the androgen-sensitivity index of BPH and prostate cancer in Gelfoam ® histoculture in a dose-dependent manner.

The Effects of Gamma and Proton Radiation Exposure on Hematopoietic Cell Counts in the Ferret Model

PubMed Central

Sanzari, Jenine K.; Wan, X. Steven; Krigsfeld, Gabriel S.; Wroe, Andrew J.; Gridley, Daila S.; Kennedy, Ann R.

2014-01-01

Exposure to total-body radiation induces hematological changes, which can detriment one's immune response to wounds and infection. Here, the decreases in blood cell counts after acute radiation doses of γ-ray or proton radiation exposure, at the doses and dose-rates expected during a solar particle event (SPE), are reported in the ferret model system. Following the exposure to γ-ray or proton radiation, the ferret peripheral total white blood cell (WBC) and lymphocyte counts decreased whereas neutrophil count increased within 3 hours. At 48 hours after irradiation, the WBC, neutrophil, and lymphocyte counts decreased in a dose-dependent manner but were not significantly affected by the radiation type (γ-rays verses protons) or dose rate (0.5 Gy/minute verses 0.5 Gy/hour). The loss of these blood cells could accompany and contribute to the physiological symptoms of the acute radiation syndrome (ARS). PMID:25356435

Evaluation of Chromosomal Instability in Diabetic Rats Treated with Naringin

PubMed Central

A. Bakheet, Saleh; M. Attia, Sabry

2011-01-01

We used the bone marrow DNA strand breaks, micronucleus formations, spermatocyte chromosomal aberrations, and sperm characteristic assays to investigate the chromosomal instability in somatic and germinal cells of diabetic rats treated with multiple doses of naringin. The obtained results revealed that naringin was neither cytotoxic nor genotoxic for the rats at all tested doses. Moreover, naringin significantly reduced the diabetes-induced chromosomal instability in somatic and germinal cells in a dose-dependent manner. In addition, diabetes induced marked biochemical alterations characteristic of oxidative stress including enhanced lipid peroxidation, accumulation of oxidized glutathione, reduction in reduced glutathione, and accumulation of intracellular reactive oxygen species. Treatment with naringin ameliorated these biochemical markers dose-dependently. In conclusion, naringin confers an appealing protective effect against diabetes-induced chromosomal instability towards rat somatic and germinal cells which might be explained partially via diminishing the de novo free radical generation induced by hyperglycemia. Thus, naringin might be a good candidate to reduce genotoxic risk associated with hyperglycemia and may provide decreases in the development of secondary malignancy and abnormal reproductive outcomes risks, which seems especially important for diabetic patients. PMID:21941606

Anti-dengue efficacy of bioactive andrographolide from Andrographis paniculata (Lamiales: Acanthaceae) against the primary dengue vector Aedes aegypti (Diptera: Culicidae).

PubMed

Edwin, Edward-Sam; Vasantha-Srinivasan, Prabhakaran; Senthil-Nathan, Sengottayan; Thanigaivel, Annamalai; Ponsankar, Athirstam; Pradeepa, Venkatraman; Selin-Rani, Selvaraj; Kalaivani, Kandaswamy; Hunter, Wayne B; Abdel-Megeed, Ahmed; Duraipandiyan, Veeramuthu; Al-Dhabi, Naif Abdullah

2016-11-01

The current study investigated the toxic effect of the leaf extract compound andrographolide from Andrographis paniculata (Burm.f) against the dengue vector Ae. aegypti. GC-MS analysis revealed that andrographolide was recognized as the major chemical constituent with the prominent peak area compared with other compounds. All isolated toxic compounds were purified and confirmed through RP-HPLC against chemical standards. The larvicidal assays established at 25ppm of bioactive compound against the treated instars of Ae. Aegypti showed prominent mortality compared to other treated concentrations. The percent mortality of larvae was directly proportional to concentration. The lethal concentration (LC50) was observed at 12ppm treatment concentration. The bioactive andrographolide considerably reduced the detoxifying enzyme regulations of α- and β- carboxylesterases. In contrast, the levels of GST and CYP450 significantly increase in a dose dependent manner. The andrographolide also showed strong oviposition deterrence effects at the sub-lethal dose of 12ppm. Similarly, the mean number of eggs were also significantly reduced in a dose dependent manner. At the concentration of 12ppm the effective percentage of repellency was greater than 90% with a protection time of 15-210min, compared with control. The histopathology study displayed that larvae treated with bioactive andrographolide had cytopathic effects in the midgut epithelium compared with the control. The present study established that bioactive andrographolide served as a potential useful for dengue vector management. Copyright © 2016 Elsevier B.V. All rights reserved.

Cinnamic acid exerts anti-diabetic activity by improving glucose tolerance in vivo and by stimulating insulin secretion in vitro.

PubMed

Hafizur, Rahman M; Hameed, Abdul; Shukrana, Mishkat; Raza, Sayed Ali; Chishti, Sidra; Kabir, Nurul; Siddiqui, Rehan A

2015-02-15

Although the anti-diabetic activity of cinnamic acid, a pure compound from cinnamon, has been reported but its mechanism(s) is not yet clear. The present study was designed to explore the possible mechanism(s) of anti-diabetic activity of cinnamic acid in in vitro and in vivo non-obese type 2 diabetic rats. Non-obese type 2 diabetes was developed by injecting 90 mg/kg streptozotocin in 2-day-old Wistar pups. Cinnamic acid and cinnamaldehyde were administered orally to diabetic rats for assessing acute blood glucose lowering effect and improvement of glucose tolerance. Additionally, insulin secretory activity of cinnamic acid and cinnamaldehyde was evaluated in isolated mice islets. Cinnamic acid, but not cinnamaldehyde, decreased blood glucose levels in diabetic rats in a time- and dose-dependent manner. Oral administration of cinnamic acid with 5 and 10 mg/kg doses to diabetic rats improved glucose tolerance in a dose-dependent manner. The improvement by 10 mg/kg cinnamic acid was comparable to that of standard drug glibenclamide (5 mg/kg). Further in vitro studies showed that cinnamaldehyde has little or no effect on glucose-stimulated insulin secretion; however, cinnamic acid significantly enhanced glucose-stimulated insulin secretion in isolated islets. In conclusion, it can be said that cinnamic acid exerts anti-diabetic activity by improving glucose tolerance in vivo and stimulating insulin secretion in vitro. Copyright © 2015 Elsevier GmbH. All rights reserved.

Protective effect of ethyl acetate fraction of Rhododendron arboreum flowers against carbon tetrachloride-induced hepatotoxicity in experimental models

PubMed Central

Verma, Neeraj; Singh, Anil P.; Amresh, G.; Sahu, P. K.; Rao, Ch. V.

2011-01-01

Objective: To evaluate the hepatoprotective potential of ethyl acetate fraction of Rhododendron arboreum (Family: Ericaceae) in Wistar rats against carbon tetrachloride (CCl4)-induced liver damage in preventive and curative models. Materials and Methods: Fraction at a dose of 100, 200, and 400 mg/kg was administered orally once daily for 14 days in CCl4-treated groups (II, III, IV, V and VI). The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), γ-glutamyltransferase (γ -GT), and bilirubin were estimated along with activities of glutathione S-transferase (GST), glutathione reductase, hepatic malondialdehyde formation, and glutathione content. Result and Discussion: The substantially elevated serum enzymatic activities of SGOT, SGPT, SALP, γ-GT, and bilirubin due to CCl4 treatment were restored toward normal in a dose-dependent manner. Meanwhile, the decreased activities of GST and glutathione reductase were also restored toward normal. In addition, ethyl acetate fraction also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl4-intoxicated rats in a dose-dependent manner. Silymarin used as standard reference also exhibited significant hepatoprotective activity on post-treatment against CCl4-induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethyl acetate fraction has a potent hepatoprotective action against CCl4-induced hepatic damage in rats. PMID:21713093

Protective effect of ethyl acetate fraction of Rhododendron arboreum flowers against carbon tetrachloride-induced hepatotoxicity in experimental models.

PubMed

Verma, Neeraj; Singh, Anil P; Amresh, G; Sahu, P K; Rao, Ch V

2011-05-01

To evaluate the hepatoprotective potential of ethyl acetate fraction of Rhododendron arboreum (Family: Ericaceae) in Wistar rats against carbon tetrachloride (CCl(4))-induced liver damage in preventive and curative models. Fraction at a dose of 100, 200, and 400 mg/kg was administered orally once daily for 14 days in CCl(4)-treated groups (II, III, IV, V and VI). The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), γ-glutamyltransferase (γ -GT), and bilirubin were estimated along with activities of glutathione S-transferase (GST), glutathione reductase, hepatic malondialdehyde formation, and glutathione content. The substantially elevated serum enzymatic activities of SGOT, SGPT, SALP, γ-GT, and bilirubin due to CCl(4) treatment were restored toward normal in a dose-dependent manner. Meanwhile, the decreased activities of GST and glutathione reductase were also restored toward normal. In addition, ethyl acetate fraction also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl(4)-intoxicated rats in a dose-dependent manner. Silymarin used as standard reference also exhibited significant hepatoprotective activity on post-treatment against CCl(4)-induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethyl acetate fraction has a potent hepatoprotective action against CCl(4)-induced hepatic damage in rats.

Impact of ketorolac administration around ovarian stimulation on in vivo and in vitro fertilization and subsequent embryo development.

PubMed

Jee, Byung Chul; Youm, Hye Won; Lee, Jae Ho; Kim, Jee Hyun; Suh, Chang Suk; Kim, Seok Hyun

2013-05-01

We performed this study to investigate the effect of ketorolac (a non-steroidal anti-inflammatory drug) administration around ovarian stimulation on in vivo and in vitro fertilization process. Sixty-four female mice (ICR) were injected with ketorolac (0, 7.5, 15 and 30 µg/d) for 3 d starting from the day of eCG treatment. In experiment 1, 41 mice were triggered by hCG and then mated; two-cell embryos were obtained and in vitro development up to blastocyst was observed. In experiment 2, 23 mice were triggered by hCG and mature oocytes were collected; in vitro fertilization rate and subsequent embryo development up to blastocyst was recorded. In experiment 1, the blastocyst-forming rates per in vivo fertilized two-cell embryo showed an inverse relationship with a dosage of ketorolac (97.6%, 64.2%, 35.4% and 25.9%). In experiment 2, degenerated oocytes were frequently observed in a dose-dependent manner (4.3%, 22.9%, 22.4% and 75.0%). Lower fertilization rates were noted in all the three ketorolac-treating groups; blastocyst-forming rate was significantly lower in 30-µg-treating group when compared with the control group. Administration of ketorolac around ovarian stimulation significantly affects the development of in vivo fertilized embryo in a dose-dependent manner. High-dose ketorolac could result in a poor oocyte quality and decreased embryo developmental competence.

Mechanisms of morphine enhancement of spontaneous seizure activity.

PubMed

Saboory, Ehsan; Derchansky, Miron; Ismaili, Mohammed; Jahromi, Shokrollah S; Brull, Richard; Carlen, Peter L; El Beheiry, Hossam

2007-12-01

High-dose opioid therapy can precipitate seizures; however, the mechanism of such a dangerous adverse effect remains poorly understood. The aim of our study was to determine whether the neuroexcitatory activity of high-dose morphine is mediated by selective stimulation of opioid receptors. Mice hippocampi were resected intact and bathed in low magnesium artificial cerebrospinal fluid to induce spontaneous seizure-like events recorded from CA1 neurons. Application of morphine had a biphasic effect on the recorded spontaneous seizure-like events. In a low concentration (10 microM), morphine depressed electrographic seizure activity. Higher morphine concentrations (30 and 100 microM) enhanced seizure activity in an apparent dose-dependent manner. Naloxone, a nonselective opiate antagonist blocked the proconvulsant action of morphine. Selective mu and kappa opiate receptor agonists and antagonists enhanced and suppressed the spontaneous seizure activity, respectively. On the contrary, delta opioid receptor ligands did not have an effect. The proseizure effect of morphine is mediated through selective stimulation of mu and kappa opiate receptors but not the activation of the delta receptor system. The observed dose-dependent mechanism of morphine neuroexcitation underscores careful adjustment and individualized opioid dosing in the clinical setting.

Adaptation and Sensitization to Proteotoxic Stress

PubMed Central

Leak, Rehana K.

2014-01-01

Although severe stress can elicit toxicity, mild stress often elicits adaptations. Here we review the literature on stress-induced adaptations versus stress sensitization in models of neurodegenerative diseases. We also describe our recent findings that chronic proteotoxic stress can elicit adaptations if the dose is low but that high-dose proteotoxic stress sensitizes cells to subsequent challenges. In these experiments, long-term, low-dose proteasome inhibition elicited protection in a superoxide dismutase-dependent manner. In contrast, acute, high-dose proteotoxic stress sensitized cells to subsequent proteotoxic challenges by eliciting catastrophic loss of glutathione. However, even in the latter model of synergistic toxicity, several defensive proteins were upregulated by severe proteotoxicity. This led us to wonder whether high-dose proteotoxic stress can elicit protection against subsequent challenges in astrocytes, a cell type well known for their resilience. In support of this new hypothesis, we found that the astrocytes that survived severe proteotoxicity became harder to kill. The adaptive mechanism was glutathione dependent. If these findings can be generalized to the human brain, similar endogenous adaptations may help explain why neurodegenerative diseases are so delayed in appearance and so slow to progress. In contrast, sensitization to severe stress may explain why defenses eventually collapse in vulnerable neurons. PMID:24659932

Redox Signaling and Bioenergetics Influence Lung Cancer Cell Line Sensitivity to the Isoflavone ME-344

PubMed Central

Manevich, Yefim; Reyes, Leticia; Britten, Carolyn D.; Townsend, Danyelle M.

2016-01-01

ME-344 [(3R,4S)-3,4-bis(4-hydroxyphenyl)-8-methyl-3,4-dihydro-2H-chromen-7-ol] is a second-generation derivative natural product isoflavone presently under clinical development. ME-344 effects were compared in lung cancer cell lines that are either intrinsically sensitive or resistant to the drug and in primary immortalized human lung embryonic fibroblasts (IHLEF). Cytotoxicity at low micromolar concentrations occurred only in sensitive cell lines, causing redox stress, decreased mitochondrial ATP production, and subsequent disruption of mitochondrial function. In a dose-dependent manner the drug caused instantaneous and pronounced inhibition of oxygen consumption rates (OCR) in drug-sensitive cells (quantitatively significantly less in drug-resistant cells). This was consistent with targeting of mitochondria by ME-344, with specific effects on the respiratory chain (resistance correlated with higher glycolytic indexes). OCR inhibition did not occur in primary IHLEF. ME-344 increased extracellular acidification rates in drug-resistant cells (significantly less in drug-sensitive cells), implying that ME-344 targets mitochondrial proton pumps. Only in drug-sensitive cells did ME-344 dose-dependently increase the intracellular generation of reactive oxygen species and cause oxidation of total (mainly glutathione) and protein thiols and the concomitant immediate increases in NADPH levels. We conclude that ME-344 causes complex, redox-specific, and mitochondria-targeted effects in lung cancer cells, which differ in extent from normal cells, correlate with drug sensitivity, and provide indications of a beneficial in vitro therapeutic index. PMID:27255112

A first‐in‐human pharmacodynamic and pharmacokinetic study of a fully human anti‐glucagon receptor monoclonal antibody in normal healthy volunteers

PubMed Central

Kostic, Ana; King, Thomas Alexander; Yang, Feng; Chan, Kuo‐Chen; Yancopoulos, George D.; Gromada, Jesper

2017-01-01

Aims Glucagon receptor (GCGR) blockers are being investigated as potential therapeutics for type 1 and type 2 diabetes. Here we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of REGN1193, a fully human glucagon receptor blocking monoclonal antibody from a first‐in‐human healthy volunteer randomized double‐blinded trial. Methods Healthy men and women received single ascending doses of REGN1193 ranging from 0.05 to 0.6 mg/kg (n = 42) or placebo (n = 14) intravenously. Safety, tolerability and PK were assessed over 106 days. The glucose‐lowering effect of REGN1193 was assessed after induction of hyperglycaemia by serial glucagon challenges. Results REGN1193 was generally well tolerated. There were small (<3× the upper limit of normal) and transient dose‐dependent increases in hepatic aminotransferases. No increase in LDL‐C was observed. Hypoglycaemia, assessed as laboratory blood glucose ≤70 mg/dL, occurred in 6/14 (43%) subjects on placebo and 27/42 (57%) on REGN1193 across all dose groups. All episodes of hypoglycaemia were asymptomatic, >50 mg/dL, and did not require treatment or medical assistance. Concentration‐time profiles suggest a 2‐compartment disposition and marked nonlinearity, consistent with target‐mediated clearance. REGN1193 inhibited the glucagon‐stimulated glucose increase in a dose‐dependent manner. The 0.6 mg/kg dose inhibited the glucagon‐induced glucose area under the curve for 0 to 90 minutes (AUC0‐90 minutes) by 80% to 90% on days 3 and 15, while blunting the increase in C‐peptide. REGN1193 dose‐dependently increased total GLP‐1, GLP‐2 and glucagon, with plasma levels returning to baseline by day 29 in all dose groups. Conclusion REGN1193, a GCGR‐blocking monoclonal antibody, produced a safety, tolerability and PK/PD profile suitable for further clinical development. The occurrence of transient elevations in serum hepatic aminotransferases observed here and reported with several small molecule glucagon receptor antagonists suggests an on‐target effect of glucagon receptor blockade. The underlying mechanism is unknown. PMID:28755409

Antithyroid drug-related hepatotoxicity in hyperthyroidism patients: a population-based cohort study

PubMed Central

Wang, Meng-Ting; Lee, Wan-Ju; Huang, Tien-Yu; Chu, Che-Li; Hsieh, Chang-Hsun

2014-01-01

Aims The evidence of hepatotoxicity of antithyroid drugs (ATDs) is limited to case reports or spontaneous reporting. This study aimed to quantify the incidence and comparative risks of hepatotoxicity for methimazole (MMI)/carbimazole (CBM) vs. propylthiouracil (PTU) in a population-based manner. Methods We conducted a cohort study of hyperthyroidism patients initially receiving MMI/CBM or PTU between 1 January 2004 and 31 December 2008 using the Taiwan National Health Insurance Research Database. The examined hepatotoxicity consisted of cholestasis, non-infectious hepatitis, acute liver failure and liver transplant, with the incidences and relative risks being quantified by Poisson exact methods and Cox proportional hazard models, respectively. Results The study cohort comprised 71 379 ATD initiators, with a median follow-up of 196 days. MMI/CBM vs. PTU users had a higher hepatitis incidence rate (3.17/1000 vs. 1.19/1000 person-years) but a lower incidence of acute liver failure (0.32/1000 vs. 0.68/1000 person-years). The relative risk analysis indicated that any use of MMI/CBM was associated with a 2.89-fold (95% CI 1.81, 4.60) increased hepatitis risk compared with PTU, with the risk increasing to 5.08-fold for high dose MMI/CBM (95% CI 3.15, 8.18). However, any MMI/CBM use vs. PTU was not related to an increased risk of cholestasis (adjusted hazard ratio [HR] 1.14, 95% CI 0.40, 3.72) or acute liver failure (adjusted HR 0.54, 95% CI 0.24, 1.22). Conclusions MMI/CBM and PTU exert dissimilar incidence rates of hepatotoxicity. Compared to PTU, MMI/CBM are associated in a dose-dependent manner with an increased risk for hepatitis while the risks are similar for acute liver failure and cholestasis. PMID:25279406

Recirculating cardiac delivery of AAV2/1SERCA2a improves myocardial function in an experimental model of heart failure in large animals.

PubMed

Byrne, M J; Power, J M; Preovolos, A; Mariani, J A; Hajjar, R J; Kaye, D M

2008-12-01

Abnormal excitation-contraction coupling is a key pathophysiologic component of heart failure (HF), and at a molecular level reduced expression of the sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA2a) is a major contributor. Previous studies in small animals have suggested that restoration of SERCA function is beneficial in HF. Despite this promise, the means by which this information might be translated into potential clinical application remains uncertain. Using a recently established cardiac-directed recirculating method of gene delivery, we administered adeno-associated virus 2 (AAV2)/1SERCA2a to sheep with pacing-induced HF. We explored the effects of differing doses of AAV2/1SERCA2a (low 1 x 10(10) d.r.p.; medium 1 x 10(12) d.r.p. and high 1 x 10(13) d.r.p.) in conjunction with an intra-coronary delivery group (2.5 x 10(13) d.r.p.). At the end of the study, haemodynamic, echocardiographic, histopathologic and molecular biologic assessments were performed. Cardiac recirculation delivery of AAV2/1SERCA2a elicited a dose-dependent improvement in cardiac performance determined by left ventricular pressure analysis, (+d P/d t(max); low dose -220+/-70, P>0.05; medium dose 125+/-53, P<0.05; high dose 287+/-104, P<0.05) and echocardiographically (fractional shortening: low dose -3+/-2, P>0.05; medium dose 1+/-2, P>0.05; high dose 6.5+/-3.9, P<0.05). In addition to favourable haemodynamic effects, brain natriuretic peptide expression was reduced consistent with reversal of the HF molecular phenotype. In contrast, direct intra-coronary infusion did not elicit any effect on ventricular function. As such, AAV2/1SERCA2a elicits favourable functional and molecular actions when delivered in a mechanically targeted manner in an experimental model of HF. These observations lay a platform for potential clinical translation.

Characterization of optically stimulated luminescence dosemeters to measure organ doses in diagnostic radiology

PubMed Central

Endo, A; Katoh, T; Kobayashi, I; Joshi, R; Sur, J; Okano, T

2012-01-01

Objective The aim of this study was to assess the characteristics of an optically stimulated luminescence dosemeter (OSLD) for use in diagnostic radiology and to apply the OSLD in measuring the organ doses by panoramic radiography. Methods The dose linearity, energy dependency and angular dependency of aluminium oxide-based OSLDs were examined using an X-ray generator to simulate various exposure settings in diagnostic radiology. The organ doses were then measured by inserting the dosemeters into an anthropomorphic phantom while using three panoramic machines. Results The dosemeters demonstrated consistent dose linearity (coefficient of variation<1.5%) and no significant energy dependency (coefficient of variation<1.5%) under the applied exposure conditions. They also exhibited negligible angular dependency (≤10%). The organ doses of the X-ray as a result of panoramic imaging by three machines were calculated using the dosemeters. Conclusion OSLDs can be utilized to measure the organ doses in diagnostic radiology. The availability of these dosemeters in strip form proves to be reliably advantageous. PMID:22116136

Melanosome uptake is associated with the proliferation and differentiation of keratinocytes.

PubMed

Choi, Hye-In; Sohn, Kyung-Cheol; Hong, Dong-Kyun; Lee, Young; Kim, Chang Deok; Yoon, Tae-Jin; Park, Jin Woon; Jung, Sunggyun; Lee, Jeung-Hoon; Lee, Young Ho

2014-01-01

Melanosomes are synthesized in melanocytes and transferred to neighboring keratinocytes. However, the associations of melanosome uptake with the proliferation and differentiation of keratinocytes are not fully understood. We examined the associations of melanosome uptake with keratinocyte differentiation and proliferation. SV40T-transformed human epidermal keratinocytes (SV-HEKs) were treated with isolated melanosomes. The effects of melanosome uptake on the proliferation and differentiation of the keratinocytes were analyzed by Western blotting and flow cytometry. The relationship between melanosome uptake and keratinocyte differentiation status was verified by determining the melanin content in the cells. Melanosomes reduced the proliferation of SV-HEKs in a dose-dependent manner, but did not induce differentiation. Melanosome uptake was higher in differentiating keratinocytes compared to non-differentiating keratinocytes, and inhibited significantly by PAR-2 inhibitor. Melanosomes inhibit keratinocyte proliferation. Moreover, melanosome uptake is influenced by keratinocyte differentiation status, being highest in mid-stage differentiating keratinocytes in a PAR-2 dependent manner.

L-carnosine affects the growth of Saccharomyces cerevisiae in a metabolism-dependent manner.

PubMed

Cartwright, Stephanie P; Bill, Roslyn M; Hipkiss, Alan R

2012-01-01

The dipeptide L-carnosine (β-alanyl-L-histidine) has been described as enigmatic: it inhibits growth of cancer cells but delays senescence in cultured human fibroblasts and extends the lifespan of male fruit flies. In an attempt to understand these observations, the effects of L-carnosine on the model eukaryote, Saccharomyces cerevisiae, were examined on account of its unique metabolic properties; S. cerevisiae can respire aerobically, but like some tumor cells, it can also exhibit a metabolism in which aerobic respiration is down regulated. L-Carnosine exhibited both inhibitory and stimulatory effects on yeast cells, dependent upon the carbon source in the growth medium. When yeast cells were not reliant on oxidative phosphorylation for energy generation (e.g. when grown on a fermentable carbon source such as 2% glucose), 10-30 mM L-carnosine slowed growth rates in a dose-dependent manner and increased cell death by up to 17%. In contrast, in media containing a non-fermentable carbon source in which yeast are dependent on aerobic respiration (e.g. 2% glycerol), L-carnosine did not provoke cell death. This latter observation was confirmed in the respiratory yeast, Pichia pastoris. Moreover, when deletion strains in the yeast nutrient-sensing pathway were treated with L-carnosine, the cells showed resistance to its inhibitory effects. These findings suggest that L-carnosine affects cells in a metabolism-dependent manner and provide a rationale for its effects on different cell types.

Effect of N-acetylcysteine administration on homocysteine level, oxidative damage to proteins, and levels of iron (Fe) and Fe-related proteins in lead-exposed workers.

PubMed

Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Aleksandra; Romuk, Ewa; Rykaczewska-Czerwińska, Monika; Pawlas, Natalia; Birkner, Ewa

2016-09-01

N-Acetylcysteine (NAC) could be included in protocols designed for the treatment of lead toxicity. Therefore, in this study, we decided to investigate the influence of NAC administration on homocysteine (Hcy) levels, oxidative damage to proteins, and the levels of iron (Fe), transferrin (TRF), and haptoglobin (HPG) in lead (Pb)-exposed workers. The examined population (n = 171) was composed of male employees who worked with Pb. They were randomized into four groups. Workers who were not administered any antioxidants, drugs, vitamins, or dietary supplements were classified as the reference group (n = 49). The remaining three groups consisted of workers who were treated orally with NAC at three different doses (1 × 200, 2 × 200, or 2 × 400 mg) for 12 weeks. After the treatment, blood Pb levels significantly decreased in the groups receiving NAC compared with the reference group. The protein concentration was not affected by NAC administration. In contrast, Hcy levels significantly decreased or showed a strong tendency toward lower values depending on the NAC dose. Levels of the protein carbonyl groups were significantly decreased in all of the groups receiving NAC. Conversely, glutamate dehydrogenase activity was significantly elevated in all of the groups receiving NAC, while the level of protein thiol groups was significantly elevated only in the group receiving 200 mg of NAC. Treatment with NAC did not significantly affect Fe and TRF levels, whereas HPG levels showed a tendency toward lower values. Treatment with NAC normalized the level of Hcy and decreased oxidative stress as measured by the protein carbonyl content; this effect occurred in a dose-dependent manner. Moreover, small doses of NAC elevated the levels of protein thiol groups. Therefore, NAC could be introduced as an alternative therapy for chronic Pb toxicity in humans. © The Author(s) 2015.

Cytokinesis-block micronucleus assay in primary human liver fibroblasts exposed to griseofulvin and mitomycin C.

PubMed

Nesti, C; Trippi, F; Scarpato, R; Migliore, L; Turchi, G

2000-03-01

Primary liver fibroblasts were applied in a cytokinesis-block micronucleus assay in combination with fluorescence in situ hybridization (FISH) using two protocols. In protocol A (Prot. A), cytochalasin B (Cyt B) was added at the end of the treatment time directly to the medium containing the standard compounds, whereas in protocol B (Prot. B) the chemical-containing medium was removed and fresh medium with Cyt B was added. The study was performed using the aneugen griseofulvin (GF) and the clastogen mitomycin C (MMC) as standard compounds. With both protocols GF induced a significant increase in MN frequency over controls in a dose-related manner at the lower concentrations tested (7.5 and 15 microg/ml). At the highest dose (30 microg/ml) the aneugen effect was substantially reduced. MN induction obtained with Prot. A was significantly higher ( approximately 3-fold) than with Prot. B at the most effective concentration. The aneugen effect induced by GF did not change when different cell densities were used, but again with Prot. A we obtained the highest effect. MN induced by MMC showed a dose- and time-dependent increase in both protocols. In contrast to GF, the greater clastogenic response induced by MMC in human liver fibroblasts was obtained with Prot. B, approximately 3-fold higher than Prot. A at the most effective concentration and approximately 2-fold with 24 h treatment at 0.17 microg/ml MMC. With GF, the FISH data in human liver fibroblasts (80% C+MN) were fairly consistent with those obtained in the rodent cell lines. In human whole blood cultures, the same dose used in our experiment produced a relatively higher percentage of C+MN. FISH analysis showed that MMC induced mainly MN containing acentric fragments rather than whole chromosomes. In conclusion we have demostrated that chemically induced genetic effects are strongly dependent on the cell culture employed, treatment schedule and intra- and post-treatment experimental conditions.

Gastroprotective effects of arctigenin of Arctium lappa L. on a rat model of gastric ulcers

PubMed Central

Li, Xiao-Mei; Miao, Yu; Su, Qin-Yong; Yao, Jing-Chun; Li, Hong-Hua; Zhang, Gui-Min

2016-01-01

In the present study, the gastroprotective effects of arctigenin of Fructus Arctii were evaluated and the possible underlying mechanisms of action were elucidated. Arctigenin (high-performance liquid chromatography purity, >99.0%) was isolated and purified from the seeds of Arctium lappa L. The anti-ulcerogenic activity of arctigenin against ulcers induced by absolute ethanol and acetic acid was evaluated in a Sprague-Dawley rat model. In addition, the antioxidant activity was assessed by measuring malondialdehyde (MDA) levels in an ethanol-induced model and the anti-inflammatory effects were assessed by measuring five factors in an acetic acid-induced model. In the ethanol-induced model, arctigenin inhibited gastric lesions in a dose-dependent manner, by 53.04, 53.91 and 64.43% at doses of 0.05, 0.15 and 0.45 mg/kg, respectively. In addition, arctigenin reduced MDA (P<0.01) and increased superoxide dismutase (P<0.01) levels in serum when compared with the vehicle group. The lesion index induced by acetic acid was significantly inhibited by all doses of arctigenin (0.05, 0.15 and 0.45 mg/kg; P<0.01) in comparison to the vehicle group and in a dose-dependent manner. In addition, it was shown that the expression levels of tumor necrosis factor-α, interleukin-6 (IL-6), IL-10 and C-reactive protein were significantly decreased (P<0.05) in the arctigenin group compared with the vehicle group. Thus, the current study indicated that arctigenin exerted anti-ulcer activity, which may be associated with its reduction in oxidative and inflammatory damage. All the results indicate that arctigenin may be used as an effective therapeutic agent to prevent gastric ulcers. PMID:27882222

Cumulative and antagonistic effects of a mixture of the antiandrogens vinclozolin and iprodione in the pubertal male rat.

PubMed

Blystone, Chad R; Lambright, Christy S; Cardon, Mary C; Furr, Johnathan; Rider, Cynthia V; Hartig, Phillip C; Wilson, Vickie S; Gray, Leon E

2009-09-01

Vinclozolin and iprodione are dicarboximide fungicides that display antiandrogenic effects in the male rat, which suggests that a mixture would lead to cumulative effects on androgen-sensitive end points. Iprodione is a steroid synthesis inhibitor, but androgen receptor antagonist activity, which is displayed by vinclozolin, has not been fully evaluated. Here, we demonstrate that iprodione binds to the human androgen receptor (IC(50) = 86.0 microM), reduces androgen-dependent gene expression, and reduces androgen-sensitive tissue weights in castrated male rats (Hershberger assay). Since vinclozolin and iprodione affect common targets in the pubertal male rat, we tested the hypothesis that a mixture would have cumulative antiandrogenic effects. An iprodione dose, that does not significantly affect androgen-dependent morphological end points, was combined with vinclozolin doses (2 x 5 factorial design). Sprague-Dawley rats were dosed by gavage with vinclozolin at 0, 10, 30, 60, and 100 mg/kg/day with and without 50 mg iprodione/kg/day from postnatal day (PND) 23 to 55-57 (n = 8 per group). The age at puberty (preputial separation [PPS]), organ weights, serum hormones, and ex vivo testis steroid hormone production were measured. Vinclozolin delayed PPS, reduced androgen-sensitive organ weights, and increased serum testosterone. The addition of iprodione enhanced the vinclozolin inhibition of PPS (PND 47.5 vs.49.1; two-way ANOVA: iprodione main effect p = 0.0002). The dose response for several reproductive and nonreproductive organ weights was affected in a cumulative manner. In contrast, iprodione antagonized the vinclozolin-induced increase in serum testosterone. These results demonstrate that these fungicides interact on common targets in a tissue-specific manner when coadministered to the pubertal male rat.

Profound prevention of experimental brain metastases of breast cancer by temozolomide in an MGMT-dependent manner

PubMed Central

Palmieri, Diane; Duchnowska, Renata; Woditschka, Stephan; Hua, Emily; Qian, Yongzhen; Biernat, Wojciech; Sosińska-Mielcarek, Katarzyna; Gril, Brunilde; Stark, Andreas; Hewitt, Stephen; Liewehr, David J; Steinberg, Seth M; Jassem, Jacek; Steeg, Patricia S

2014-01-01

Purpose Brain metastases of breast cancer cause neurocognitive damage and are incurable. We evaluated a role for temozolomide in the prevention of brain metastases of breast cancer in experimental brain metastasis models. Experimental Design Temozolomide was administered in mice following earlier injection of brain-tropic human epidermal growth factor receptor 2 (HER2)-positive Jimt1-BR3 and triple negative 231-BR-EGFP sublines, the latter with and without expression of 06-methylguanine-DNA methyltransferase (MGMT). Additionally, the percentage of MGMT-positive tumor cells in 62 patient-matched sets of breast cancer primary tumors and resected brain metastases was determined immunohistochemically. Results Temozolomide, when dosed at 50, 25, 10 or 5 mg/kg, 5 days/week, beginning 3 days after inoculation, completely prevented the formation of experimental brain metastases from MGMT-negative 231-BR-EGFP cells. At a 1 mg/kg dose, temozolomide prevented 68% of large brain metastases, and was ineffective at a dose of 0.5 mg/kg. When the 50 mg/kg dose was administered beginning on days 18 or 24, temozolomide efficacy was reduced or absent. Temozolomide was ineffective at preventing brain metastases in MGMT-transduced 231-BR-EGFP and MGMT-expressing Jimt-1-BR3 sublines. In 62 patient-matched sets of primary breast tumors and resected brain metastases, 43.5% of the specimens had concordant low MGMT expression, while in another 14.5% of sets high MGMT staining in the primary tumor corresponded with low staining in the brain metastasis. Conclusions Temozolomide profoundly prevented the outgrowth of experimental brain metastases of breast cancer in an MGMT-dependent manner. These data provide compelling rationale for investigating the preventive efficacy of temozolomide in a clinical setting. PMID:24634373

Profound prevention of experimental brain metastases of breast cancer by temozolomide in an MGMT-dependent manner.

PubMed

Palmieri, Diane; Duchnowska, Renata; Woditschka, Stephan; Hua, Emily; Qian, Yongzhen; Biernat, Wojciech; Sosińska-Mielcarek, Katarzyna; Gril, Brunilde; Stark, Andreas M; Hewitt, Stephen M; Liewehr, David J; Steinberg, Seth M; Jassem, Jacek; Steeg, Patricia S

2014-05-15

Brain metastases of breast cancer cause neurocognitive damage and are incurable. We evaluated a role for temozolomide in the prevention of brain metastases of breast cancer in experimental brain metastasis models. Temozolomide was administered in mice following earlier injection of brain-tropic HER2-positive JIMT-1-BR3 and triple-negative 231-BR-EGFP sublines, the latter with and without expression of O(6)-methylguanine-DNA methyltransferase (MGMT). In addition, the percentage of MGMT-positive tumor cells in 62 patient-matched sets of breast cancer primary tumors and resected brain metastases was determined immunohistochemically. Temozolomide, when dosed at 50, 25, 10, or 5 mg/kg, 5 days per week, beginning 3 days after inoculation, completely prevented the formation of experimental brain metastases from MGMT-negative 231-BR-EGFP cells. At a 1 mg/kg dose, temozolomide prevented 68% of large brain metastases, and was ineffective at a dose of 0.5 mg/kg. When the 50 mg/kg dose was administered beginning on days 18 or 24, temozolomide efficacy was reduced or absent. Temozolomide was ineffective at preventing brain metastases in MGMT-transduced 231-BR-EGFP and MGMT-expressing JIMT-1-BR3 sublines. In 62 patient-matched sets of primary breast tumors and resected brain metastases, 43.5% of the specimens had concordant low MGMT expression, whereas in another 14.5% of sets high MGMT staining in the primary tumor corresponded with low staining in the brain metastasis. Temozolomide profoundly prevented the outgrowth of experimental brain metastases of breast cancer in an MGMT-dependent manner. These data provide compelling rationale for investigating the preventive efficacy of temozolomide in a clinical setting. ©2014 American Association for Cancer Research.

Development and application of GC-MS method for monitoring of long-term exposure to the pesticide cypermethrin.

PubMed

Kavvalakis, Matthaios P; Tzatzarakis, Manolis N; Alegakis, Athanasios K; Vynias, Dionysios; Tsakalof, Andreas K; Tsatsakis, Aristidis M

2014-06-01

Cypermethrin (CPMN) is a synthetic pyrethroid used as an insecticide in large-scale commercial agricultural applications as well as for domestic purposes. In the present study a gas chromatography-mass spectrometry (GC-MS) based method was developed and validated for the quantitation of CPMN metabolites, 3-phenoxybenzoic acid (3-PBA) and cis- and trans- 3-(2,2-dichlorovinyl)-2,2-dimethyl-1-cyclopropane (cis- and trans- Cl2 CA). The developed method was applied for the monitoring of CPMN metabolites in hair of laboratory animals (rabbits) intentionally exposed per os to CPMN at 40 (low dose) and 80 (high dose) mg/kg weight/day for 16 weeks. The analytical method comprises three main steps: isolation of analytes from hair, analytes derivatization, and subsequent instrumental analysis by GC-MS. The limits of detection ensured by the method are 4.0, 3.9 and 1.0 pg/mg hair for cis-Cl2 CA, trans-Cl2 CA and 3-PBA, respectively. The instrument responce is linear (r(2)  > 0.99) in the investigated concentrations range from 25 to 1000 pg/mg. With and between-run precision as well as accuracy were estimated and found satisfactory. Analytes were efficiently isolated by solid-liquid extraction from hair with recoveries greater than 84.8% for cis-Cl2 CA, 87.2% for trans-Cl2 CA and 96.4% for 3-PBA. Rabbit's hair showed increasing levels for all metabolites (metabolites accumulation in a time and dose dependent manner) over time and in a dose-dependent manner. The developed experimental procedure could be used for biomonitoring of population exposure to CPMN. Copyright © 2014 John Wiley & Sons, Ltd.

Alteration in plasma and striatal levels of d-serine after d-serine administration with or without nicergoline: An in vivo microdialysis study.

PubMed

Onozato, Mayu; Nakazawa, Hiromi; Ishimaru, Katsuyuki; Nagashima, Chihiro; Fukumoto, Minori; Hakariya, Hitomi; Sakamoto, Tatsuya; Ichiba, Hideaki; Fukushima, Takeshi

2017-09-01

d-Serine (d-Ser), a co-agonist of N -methyl-d-aspartate receptor (NMDAR), is effective for treating schizophrenia. The present study investigated changes in plasma and striatal d-Ser levels in Sprague-Dawley (SD) rats after intraperitoneal d-Ser administration alone or together with nicergoline (Nic), a commercial cerebral ameliorating drug, using in vivo microdialysis (MD) to explore the function of Nic. Phosphate-buffered saline (PBS) or Nic (0, 1.0, or 3.0 mg/kg) followed by d-Ser (5.0, 10.0, 20.0, and 50.0 mg/kg for PBS or 20.0 mg/kg for Nic) was administered intraperitoneally to male SD rats, and the profiles of d-Ser levels in plasma and striatal MD samples were examined by high-performance liquid chromatography (HPLC) with fluorescence detection. The area under the curve (AUC) for the MD and plasma samples was also calculated and statistically compared among groups. AUC values of d-Ser increased in a d-Ser dose-dependent manner in plasma samples, while a proportional increase in the AUC values of striatal MD samples was only observed in d-Ser doses up to 20 mg/kg. The Nic co-administered group showed a significant increase in the AUC of plasma d-Ser in a Nic dose-dependent manner, but the AUC in striatal d-Ser significantly decreased with increasing Nic doses suggesting that Nic may prevent excess d-Ser from penetrating the central nervous system (CNS). Nic may prevent an excessive distribution of exogenous d-Ser, such as that from a dietary origin, into the CNS by suppressing excitatory neurotransmission through NMDAR.

Gastroprotective effects of arctigenin of Arctium lappa L. on a rat model of gastric ulcers.

PubMed

Li, Xiao-Mei; Miao, Yu; Su, Qin-Yong; Yao, Jing-Chun; Li, Hong-Hua; Zhang, Gui-Min

2016-11-01

In the present study, the gastroprotective effects of arctigenin of Fructus Arctii were evaluated and the possible underlying mechanisms of action were elucidated. Arctigenin (high-performance liquid chromatography purity, >99.0%) was isolated and purified from the seeds of Arctium lappa L. The anti-ulcerogenic activity of arctigenin against ulcers induced by absolute ethanol and acetic acid was evaluated in a Sprague-Dawley rat model. In addition, the antioxidant activity was assessed by measuring malondialdehyde (MDA) levels in an ethanol-induced model and the anti-inflammatory effects were assessed by measuring five factors in an acetic acid-induced model. In the ethanol-induced model, arctigenin inhibited gastric lesions in a dose-dependent manner, by 53.04, 53.91 and 64.43% at doses of 0.05, 0.15 and 0.45 mg/kg, respectively. In addition, arctigenin reduced MDA (P<0.01) and increased superoxide dismutase (P<0.01) levels in serum when compared with the vehicle group. The lesion index induced by acetic acid was significantly inhibited by all doses of arctigenin (0.05, 0.15 and 0.45 mg/kg; P<0.01) in comparison to the vehicle group and in a dose-dependent manner. In addition, it was shown that the expression levels of tumor necrosis factor-α, interleukin-6 (IL-6), IL-10 and C-reactive protein were significantly decreased (P<0.05) in the arctigenin group compared with the vehicle group. Thus, the current study indicated that arctigenin exerted anti-ulcer activity, which may be associated with its reduction in oxidative and inflammatory damage. All the results indicate that arctigenin may be used as an effective therapeutic agent to prevent gastric ulcers.

Modulation of ethoxyresorufin O-deethylase and glutathione S-transferase activities in Nile tilapia (Oreochromis niloticus) by polycyclic aromatic hydrocarbons containing two to four rings: implications in biomonitoring aquatic pollution.

PubMed

Pathiratne, Asoka; Hemachandra, Chamini K

2010-08-01

Despite ubiquity of polycyclic aromatic hydrocarbons (PAHs) in the tropical environments, little information is available concerning responses of tropical fish to PAHs and associated toxicity. In the present study, effects of five PAHs containing two to four aromatic rings on hepatic CYP1A dependent ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and serum sorbitol dehydrogenase (SDH) activities in Nile tilapia, a potential fish species for biomonitoring pollution in tropical waters, were evaluated. Results showed that EROD activities were induced by the PAHs containing four aromatic rings (pyrene and chrysene) in a dose dependent manner. However PAHs with two to three aromatic rings (naphthalene, phenanthrene and fluoranthene) caused no effect or inhibition of EROD activities depending on the dose and the duration. Fluoranthene was the most potent inhibitor. SDH results demonstrated that high doses of fluoranthene induced hepatic damage. GST activity was induced by the lowest dose of phenanthrene, fluoranthene and chrysene but high doses had no effect. The results indicate that induction of EROD enzyme in Nile tilapia is a useful biomarker of exposure to PAHs such as pyrene and chrysene. However EROD inhibiting PAHs such as fluoranthene in the natural environment may modulate the EROD inducing potential of other PAHs thereby influencing PAH exposure assessments.

Daucosterol inhibits cancer cell proliferation by inducing autophagy through reactive oxygen species-dependent manner.

PubMed

Zhao, Chuanke; She, Tiantian; Wang, Lixin; Su, Yahui; Qu, Like; Gao, Yujing; Xu, Shuo; Cai, Shaoqing; Shou, Chengchao

2015-09-15

This study aims to evaluate the anti-cancer effect of daucosterol and explore its possible mechanism. MTT and colony formation assay were performed to determine the effect of daucosterol on cancer cell proliferation in vitro. H22 allograft model was used for the assessment of its anti-cancer activity in vivo. Intracellular generation of reactive oxygen species (ROS) was measured using DCFH-DA probe with flow cytometry system and a laser scanning confocal microscope. LC3 (microtubule-associated protein 1 light chain 3)-II conversion was monitored with immunofluorescence and immunoblotting to demonstrate daucosterol-induced autophagy. We found that daucosterol inhibits the proliferation of human breast cancer cell line MCF-7 and gastric cancer cell lines MGC803, BGC823 and AGS in a dose-dependent manner. Furthermore, daucosterol inhibits murine hepatoma H22 cell growth in ICR mice. Daucosterol treatment induces intracellular ROS generation and autophagy, but not apoptotic cell death. Treatment with ROS scavenger GSH (reduced glutathione), NAC (N-acetyl-l-cysteine) or autophagy inhibitor 3-Methyladenine (3-MA) counteracted daucosterol-induced autophagy and growth inhibition in BGC823 and MCF-7 cancer cells. Daucosterol inhibits cancer cell proliferation by inducing autophagy through ROS-dependent manner and could be potentially developed as an anti-cancer agent. Copyright © 2015 Elsevier Inc. All rights reserved.

Aqueous ethanol extract of the fruit of Xylopia aethiopica (Annonaceae) exhibits anti-anaphylactic and anti-inflammatory actions in mice.

PubMed

Obiri, David D; Osafo, Newman

2013-07-30

Xylopia aethiopica has been traditionally used in the form of the dried fruit decoction to treat bronchitis, asthma, arthritis and rheumatism in Ghana, Nigeria and Cameroon. Aim of the study is to evaluate the anti-anaphylactic and anti-inflammatory effects of a 70% aqueous ethanol extract of the fruits of Xylopia aethiopica. Systemic anaphylaxis was induced by the injection of either compound 48/80 or lipopolysaccharide, LPS and survival rates of mice monitored for 1 h or 7 days respectively while IgE-mediated anaphylaxis in a local allergic reaction was studied in the pinnal inflammation model in mice. Clonidine-induced catalepsy in mice was used to evaluate the indirect antihistamine effect of Xylopia aethiopica, XAE. The effects of XAE assessed on the maximal and total oedema responses in the carrageenan-induced paw oedema in mice was used to evaluate the anti-inflammatory action of the extract. Administered at 30, 100, 300 and 1000 mg kg(-1) p.o., XAE dose dependently suppressed compound 48/80-induced mouse systemic anaphylactic shock and offered 63% protection to mice against LPS-induced endotoxic shock at a dose of 300 mg kg(-1). In addition, the extract (30-300 mg kg(-1)) in a dose dependent manner significantly inhibited by 23-62% the mouse pinnal inflammation. Clonidine-induced catalepsy in mice was significantly suppressed in a dose and time dependent manner when administered both prophylactically and therapeutically. In the same doses, when administered before the induction of the mouse carrageenan-induced paw oedema, the mean maximal swelling attained during 6 h was reduced to 41.02±6.94%, 35.61±4.30%, and 29.09±4.90% of the inflamed control response respectively and total paw swellings induced over the 6 h were also dose-dependently and significantly suppressed to 74.84±14.84%, 63.95±9.37%, and 48.13±10.90% of the inflamed control response respectively. Administered after the induction of the carrageenan paw oedema the mean maximal swelling attained during 6 h was suppressed to 49.84±3.95%, 43.62±1.01%, and 35.97±1.34% of the inflamed control response respectively while the total paw swellings induced over the 6 h were also dose-dependently and significantly suppressed at 100 and 300 mg kg(-1) to 72.39±4.38% and 60.81±3.25% of the inflamed control response respectively. These findings suggest that XAE inhibits mast cell-dependent immediate allergic reactions and exhibit anti-inflammatory actions through the inhibition of histamine release from mast cells via stabilizing the cell membrane. Our results contribute towards validation of the traditional use of Xylopia aethiopica in the treatment of bronchitis, asthma, arthritis and rheumatism. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effect of Noni (Morinda citrifolia Linn.) Fruit and Its Bioactive Principles Scopoletin and Rutin on Rat Vas Deferens Contractility: An Ex Vivo Study

PubMed Central

Narasingam, Megala; Murugan, Dharmani Devi; Mohamed, Zahurin

2014-01-01

This study examined the effect of methanolic extract of Morinda citrifolia Linn. (MMC) and its bioactive principles, scopoletin and rutin, on dopamine- and noradrenaline-evoked contractility in isolated rat vas deferens preparations. MMC (1–40 mg/mL), scopoletin (1–200 μg/mL), and rutin hydrate (0.6–312.6 μg/mL) dose-dependently inhibited the contractility evoked by submaximal concentrations of both dopamine and noradrenaline, respectively. Haloperidol and prazosin, reference dopamine D2, and α 1-adrenoceptors antagonists significantly reversed the dopamine- and noradrenaline-induced contractions, respectively, in a dose-dependent manner. Interestingly, MMC per se at higher doses (60–100 mg/mL) showed dose-dependent contractile response in rat vas deferens which was partially inhibited by high doses of haloperidol but not by prazosin. These results demonstrated the biphasic effects of MMC on dopaminergic system; that is, antidopaminergic effect at lower concentrations (<40 mg/mL) and dopaminergic agonistic effect at higher concentrations (>60 mg/mL). However, similar contractile response at high doses of scopoletin (0.5–5 mg/mL) and rutin hydrate (0.5–5 mg/mL) per se was not observed. Therefore, it can be concluded that the bioactive principles of MMC, scopoletin, and rutin might be responsible for the antidopaminergic and antiadrenergic activities of MMC. PMID:25045753

Effects of multiple ascending doses of the glucagon receptor antagonist PF-06291874 in patients with type 2 diabetes mellitus.

PubMed

Kazierad, D J; Bergman, A; Tan, B; Erion, D M; Somayaji, V; Lee, D S; Rolph, T

2016-08-01

To assess the pharmacokinetics, pharmacodynamics, safety and tolerability of multiple ascending doses of the glucagon receptor antagonist PF-06291874 in patients with type 2 diabetes mellitus (T2DM). Patients were randomized to oral PF-06291874 or placebo on a background of either metformin (Part A, Cohorts 1-5: 5-150 mg once daily), or metformin and sulphonylurea (Part B, Cohorts 1-2: 15 or 30 mg once daily) for 14-28 days. A mixed-meal tolerance test (MMTT) was administered on days -1 (baseline), 14 and 28. Assessments were conducted with regard to pharmacokinetics, various pharmacodynamic variables, safety and tolerability. Circulating amino acid concentrations were also measured. PF-06291874 exposure was approximately dose-proportional with a half-life of ∼19.7-22.7 h. Day 14 fasting plasma glucose and mean daily glucose values were reduced from baseline in a dose-dependent manner, with placebo-corrected decreases of 34.3 and 42.4 mg/dl, respectively, at the 150 mg dose. After the MMTT, dose-dependent increases in glucagon and total glucagon-like peptide-1 (GLP-1) were observed, although no meaningful changes were noted in insulin, C-peptide or active GLP-1 levels. Small dose-dependent increases in LDL cholesterol were observed, along with reversible increases in serum aminotransferases that were largely within the laboratory reference range. An increase in circulating gluconeogenic amino acids was also observed on days 2 and 14. All dose levels of PF-06291874 were well tolerated. PF-06291874 was well tolerated, has a pharmacokinetic profile suitable for once-daily dosing, and results in reductions in glucose with minimal risk of hypoglycaemia. © 2016 John Wiley & Sons Ltd.

Inhibitory effect of mast cell-mediated immediate-type allergic reactions in rats by spirulina.

PubMed

Kim, H M; Lee, E H; Cho, H H; Moon, Y H

1998-04-01

We investigated the effect of spirulina on mast cell-mediated immediate-type allergic reactions. Spirulina dose-dependently inhibited the systemic allergic reaction induced by compound 48/80 in rats. Spirulina inhibited compound 48/80-induced allergic reaction 100% with doses of 100-1000 microg/g body weight, i.p. Spirulina (10-1000 microg/g body weight, i.p.) also significantly inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. When rats were pretreated with spirulina at a concentration ranging from 0.01 to 1000 microg/g body weight, i.p., the serum histamine levels were reduced in a dose-dependent manner. Spirulina (0.001 to 10 microg/mL) dose-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP in RPMC, when spirulina (10 microg/mL) was added, transiently and significantly increased about 70-fold at 10 sec compared with that of control cells. Moreover, spirulina (10 microg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha production. These results indicate that spirulina inhibits mast cell-mediated immediate-type allergic reactions in vivo and in vitro.

Intrathecal Huperzine A Increases Thermal Escape Latency and Decreases Flinching Behavior in the Formalin Test in Rats

PubMed Central

Park, Paula; Schachter, Steven; Yaksh, Tony

2010-01-01

Huperzine A (HupA) is an alkaloid isolated from the Chinese club moss Huperzia serrata and has been used for improving memory, cognitive and behavioral function in patients with Alzheimer's disease in China. It has NMDA antagonist and anticholinesterase activity and has shown anticonvulsant and antinociceptive effects in preliminary studies when administered intraperitoneally to mice. To better characterize the antinociceptive effects of HupA at the spinal level, Holtzman rats were implanted with intrathecal catheters to measure thermal escape latency using Hargreaves thermal escape testing system and flinching behavior using the formalin test. Intrathecal (IT) administration of HupA showed a dose-dependent increase in thermal escape latency with an ED50 of 0.57 μg. Atropine reversed the increase in thermal escape latency produced by 10 μg HupA, indicating an antinociceptive mechanism through muscarinic cholinergic receptors. The formalin test showed that HupA decreased flinching behavior in a dose-dependent manner. Atropine also reversed the decrease in flinching behavior caused by 10 μg HupA. A dose-dependent increase of side effects including scratching, biting, and chewing tails was observed, although antinociceptive effects were observed in doses that did not produce any adverse effects. PMID:20026382

The effects of alpha2-adrenoceptor agents on anti-hyperalgesic effects of carbamazepine and oxcarbazepine in a rat model of inflammatory pain.

PubMed

Vucković, Sonja M; Tomić, Maja A; Stepanović-Petrović, Radica M; Ugresić, Nenad; Prostran, Milica S; Bosković, Bogdan

2006-11-01

In this study, the effects of yohimbine (alpha2-adrenoceptor antagonist) and clonidine (alpha2-adrenoceptor agonist) on anti-hyperalgesia induced by carbamazepine and oxcarbazepine in a rat model of inflammatory pain were investigated. Carbamazepine (10-40 mg/kg; i.p.) and oxcarbazepine (40-160 mg/kg; i.p.) caused a significant dose-dependent reduction of the paw inflammatory hyperalgesia induced by concanavalin A (Con A, intraplantarly) in a paw pressure test in rats. Yohimbine (1-3 mg/kg; i.p.) significantly depressed the anti-hyperalgesic effects of carbamazepine and oxcarbazepine, in a dose- and time-dependent manner. Both drug mixtures (carbamazepine-clonidine and oxcarbazepine-clonidine) administered in fixed-dose fractions of the ED50 (1/2, 1/4 and 1/8) caused significant and dose-dependent reduction of the hyperalgesia induced by Con A. Isobolographic analysis revealed a significant synergistic (supra-additive) anti-hyperalgesic effect of both combinations tested. These results indicate that anti-hyperalgesic effects of carbamazepine and oxcarbazepine are, at least partially, mediated by activation of adrenergic alpha2-receptors. In addition, synergistic interaction for anti-hyperalgesia between carbamazepine and clonidine, as well as oxcarbazepine and clonidine in a model of inflammatory hyperalgesia, was demonstrated.

Intrathecal huperzine A increases thermal escape latency and decreases flinching behavior in the formalin test in rats.

PubMed

Park, Paula; Schachter, Steven; Yaksh, Tony

2010-02-05

Huperzine A (HupA) is an alkaloid isolated from the Chinese club moss Huperzia serrata and has been used for improving memory, cognitive and behavioral function in patients with Alzheimer's disease in China. It has NMDA antagonist and anticholinesterase activity and has shown anticonvulsant and antinociceptive effects in preliminary studies when administered intraperitoneally to mice. To better characterize the antinociceptive effects of HupA at the spinal level, Holtzman rats were implanted with intrathecal catheters to measure thermal escape latency using Hargreaves thermal escape testing system and flinching behavior using the formalin test. Intrathecal (IT) administration of HupA showed a dose-dependent increase in thermal escape latency with an ED50 of 0.57 microg. Atropine reversed the increase in thermal escape latency produced by 10 microg HupA, indicating an antinociceptive mechanism through muscarinic cholinergic receptors. The formalin test showed that HupA decreased flinching behavior in a dose-dependent manner. Atropine also reversed the decrease in flinching behavior caused by 10 microg HupA. A dose-dependent increase of side effects including scratching, biting, and chewing tails was observed, although antinociceptive effects were observed in doses that did not produce any adverse effects. (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Characteristics and verification of a car-borne survey system for dose rates in air: KURAMA-II.

PubMed

Tsuda, S; Yoshida, T; Tsutsumi, M; Saito, K

2015-01-01

The car-borne survey system KURAMA-II, developed by the Kyoto University Research Reactor Institute, has been used for air dose rate mapping after the Fukushima Dai-ichi Nuclear Power Plant accident. KURAMA-II consists of a CsI(Tl) scintillation detector, a GPS device, and a control device for data processing. The dose rates monitored by KURAMA-II are based on the G(E) function (spectrum-dose conversion operator), which can precisely calculate dose rates from measured pulse-height distribution even if the energy spectrum changes significantly. The characteristics of KURAMA-II have been investigated with particular consideration to the reliability of the calculated G(E) function, dose rate dependence, statistical fluctuation, angular dependence, and energy dependence. The results indicate that 100 units of KURAMA-II systems have acceptable quality for mass monitoring of dose rates in the environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Amphetamine increases activity but not exploration in humans and mice

PubMed Central

Minassian, Arpi; Young, Jared W.; Cope, Zackary A.; Henry, Brook L.; Geyer, Mark A.; Perry, William

2015-01-01

Rationale Cross-species quantification of physiological behavior enables a better understanding of the biological systems underlying neuropsychiatric diseases such as Bipolar Disorder (BD). Cardinal symptoms of manic BD include increased motor activity and goal-directed behavior, thought to be related to increased catecholamine activity, potentially selective to dopamine homeostatic dysregulation. Objectives The objective of this study was to test whether acute administration of amphetamine, a norepinephrine/dopamine transporter inhibitor and dopamine releaser, would replicate the profile of activity and exploration observed in both humans with manic BD and mouse models of mania. Methods Healthy volunteers with no psychiatric history were randomized to a one-time dose of placebo (n=25), 10 mg d-amphetamine (n=18), or 20 mg amphetamine (n=23). 80 mice were administered one of 4 doses of d-amphetamine or vehicle. Humans and mice were tested in the Behavioral Pattern Monitor (BPM), which quantifies motor activity, exploratory behavior, and spatial patterns of behavior. Results In humans, the 20-mg dose of amphetamine increased motor activity as measured by acceleration without marked effects on exploration or spatial patterns of activity. In mice, amphetamine increased activity, decreased specific exploration, and caused straighter, one-dimensional movements in a dose-dependent manner. Conclusions Consistent with mice, amphetamine increased motoric activity in humans without increasing exploration. Given that BD patients exhibit heightened exploration, these data further emphasize the limitation of amphetamine-induced hyperactivity as a suitable model for BD. Further, these studies highlight the utility of cross-species physiological paradigms in validating biological mechanisms of psychiatric diseases. PMID:26449721

SU-F-T-06: Development of a Formalism for Practical Dose Measurements in Brachytherapy in the German Standard DIN 6803

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

Hensley, F; Chofor, N; Schoenfeld, A

2016-06-15

Purpose: In the steep dose gradients in the vicinity of a radiation source and due to the properties of the changing photon spectra, dose measurements in Brachytherapy usually have large uncertainties. Working group DIN 6803-3 is presently discussing recommendations for practical brachytherapy dosimetry incorporating recent theoretical developments in the description of brachytherapy radiation fields as well as new detectors and phantom materials. The goal is to prepare methods and instruments to verify dose calculation algorithms and for clinical dose verification with reduced uncertainties. Methods: After analysis of the distance dependent spectral changes of the radiation field surrounding brachytherapy sources, themore » energy dependent response of typical brachytherapy detectors was examined with Monte Carlo simulations. A dosimetric formalism was developed allowing the correction of their energy dependence as function of source distance for a Co-60 calibrated detector. Water equivalent phantom materials were examined with Monte Carlo calculations for their influence on brachytherapy photon spectra and for their water equivalence in terms of generating equivalent distributions of photon spectra and absorbed dose to water. Results: The energy dependence of a detector in the vicinity of a brachytherapy source can be described by defining an energy correction factor kQ for brachytherapy in the same manner as in existing dosimetry protocols which incorporates volume averaging and radiation field distortion by the detector. Solid phantom materials were identified which allow precise positioning of a detector together with small correctable deviations from absorbed dose to water. Recommendations for the selection of detectors and phantom materials are being developed for different measurements in brachytherapy. Conclusion: The introduction of kQ for brachytherapy sources may allow more systematic and comparable dose measurements. In principle, the corrections can be verified or even determined by measurement in a water phantom and comparison with dose distributions calculated using the TG43 dosimetry formalism. Project is supported by DIN Deutsches Institut fuer Normung.« less

Nonmutagenicity of betel leaf and its antimutagenic action against environmental mutagens.

PubMed

Nagabhushan, M; Amonkar, A J; D'Souza, A V; Bhide, S V

1987-01-01

Betel leaf (Piper betel) water and acetone extract are nonmutagenic in S. typhimurium strains with and without S9 mix. Both the extracts suppress the mutagenicity of betel quid mutagens in a dose dependent manner. Moreover both the extracts of betel leaf reduce the mutagenicity of benzo(a)pyrene and dimethylbenzanthracene. Acetone extract is more potent than water extract in inhibiting mutagenicity of environmental mutagens.

A cytocidal tissue kallikrein isolated from mouse submandibular glands.

PubMed

Murakami, K; Ikigai, H; Nagumo, N; Tomita, M; Shimamura, T

1989-11-06

A cytocidal factor against mouse thymocytes was purified from the submandibular glands of female BALB/c mice using Sephadex G-50 gel filtration chromatography and reverse-phase HPLC. SDS-PAGE and amino acid sequence analysis revealed that the cytocidal factor was mouse glandular kallikrein (mGK)-6. mGK-6 showed an optimal enzyme activity at pH 10 and a cytocidal activity against thymocytes in a dose-dependent manner.

Hydrogen fermentation properties of undiluted cow dung.

PubMed

Yokoyama, Hiroshi; Waki, Miyoko; Ogino, Akifumi; Ohmori, Hideyuki; Tanaka, Yasuo

2007-07-01

Anaerobic treatment of undiluted cow dung (15% total solids), so-called dry fermentation, produced hydrogen (743 ml-H(2)/kg-cow dung) at an optimum temperature of 60 degrees C, with butyrate and acetate formation. The hydrogen production was inhibited by the addition of NH(4)(+) in a dose-dependent manner. A bacterium with similarity to Clostridium cellulosi was detected in the fermented dung by a 16S rDNA analysis.

Bax Translocation Mediated Mitochondrial Apoptosis and Caspase Dependent Photosensitizing Effect of Ficus religiosa on Cancer Cells

PubMed Central

Thankayyan R, Santhosh Kumar; Sithul, Hima; Sreeharshan, Sreeja

2012-01-01

The main aim of the present work was to investigate the potential effect of acetone extract of Ficus religosa leaf (FAE) in multiple apoptosis signalling in human breast cancer cells. FAE treatment significantly induced dose and time dependent, irreversible inhibition of breast cancer cell growth with moderate toxicity to normal breast epithelial cells. This observation was validated using Sulforhodamine B assay. Cell cycle analysis by Flow cytometry showed cell cycle arrest in G1 phase and induction of sub-G0 peak. FAE induced chromatin condensation and displayed an increase in apoptotic population in Annexin V-FITC/PI (Fluorescein isothiocyanate/Propidium iodide) double staining. FAE stimulated the loss of mitochondrial membrane potential in multiple breast cancer cell lines when compared to normal diploid cells. To understand the role of Bax in FAE induced apoptosis, we employed a sensitive cell based platform of MCF-7 cells expressing Bax-EGFP. Bax translocation to mitochondria was accompanied by the disruption of mitochondrial membrane potential and marked elevation in LEHDase activity (Caspase 9). Consistent with this data, FAE induced Caspase activation as evidenced by ratio change in FRET Caspase sensor expressing MCF-7 cell line and cleavage of prominent Caspases and PARP. Interestingly, FAE accelerated cell death in a mitochondrial dependent manner in continuous live cell imaging mode indicating its possible photosensitizing effect. Intracellular generation of reactive oxygen species (ROS) by FAE played a critical role in mediating apoptotic cell death and photosensitizing activity. FAE induced dose and time dependent inhibition of cancer cell growth which was associated with Bax translocation and mitochondria mediated apoptosis with the activation of Caspase 9 dependent Caspase cascade. FAE also possessed strong photosensitizing effect on cancer cell line that was mediated through rapid mitochondrial transmembrane potential loss and partial Caspase activation involving generation of intracellular ROS. PMID:22792212

Shikonin induces apoptosis of HaCaT cells via the mitochondrial, Erk and Akt pathways

PubMed Central

JING, HUILING; SUN, WENYAN; FAN, JINGHUA; ZHANG, YANMIN; YANG, JIAO; JIA, JINJING; LI, JICHANG; GUO, JIAQI; LUO, SUJU; ZHENG, YAN

2016-01-01

Shikonin, which is a major ingredient of the traditional Chinese herb Lithospermum erythrorhizon, possesses various biological functions, including antimicrobial, anti-inflammatory, and antitumor activities. The present study aimed to determine the molecular mechanisms underlying the effects of shikonin on HaCaT cell apoptosis. Treatment with shikonin significantly inhibited the viability of HaCaT cells in a dose- and time-dependent manner, and promoted cell cycle arrest at G0/G1 phase and apoptosis. In addition, shikonin treatment reduced the mitochondrial membrane potential and induced reactive oxygen species generation. The results of a western blot analysis demonstrated that shikonin significantly activated caspase 3 expression, downregulated B-cell lymphoma 2 (Bcl-2) expression, and upregulated Bcl-2-associated X protein and Bcl-2 homologous antagonist killer expression in a dose-dependent manner in HaCaT cells. Furthermore, shikonin decreased extracellular signal-regulated kinase (Erk) and Akt phosphorylation. These results indicated that shikonin may exert its anti-proliferative effects by inducing apoptosis via activation of the mitochondrial signaling pathway and inactivation of the Akt and Erk pathways in HaCaT cells. Therefore, the present study suggested that shikonin may have potential as a component of therapeutic strategies for the treatment of skin diseases. PMID:26935874

Arachidonic acid induces macrophage cell cycle arrest through the JNK signaling pathway.

PubMed

Shen, Ziying; Ma, Yunqing; Ji, Zhonghao; Hao, Yang; Yan, Xuan; Zhong, Yuan; Tang, Xiaochun; Ren, Wenzhi

2018-02-09

Arachidonic acid (AA) has potent pro-apoptotic effects on cancer cells at a low concentration and on macrophages at a very high concentration. However, the effects of AA on the macrophage cell cycle and related signaling pathways have not been fully investigated. Herein we aim to observe the effect of AA on macrophages cell cycle. AA exposure reduced the viability and number of macrophages in a dose- and time-dependent manner. The reduction in RAW264.7 cell viability was not caused by apoptosis, as indicated by caspase-3 and activated caspase-3 detection. Further research illustrated that AA exposure induced RAW264.7 cell cycle arrested at S phase, and some cell cycle-regulated proteins were altered accordingly. Moreover, JNK signaling was stimulated by AA, and the stimulation was partially reversed by a JNK signaling inhibitor in accordance with cell cycle-related factors. In addition, nuclear and total Foxo1/3a and phosphorylated Foxo1/3a were elevated by AA in a dose- and time-dependent manner, and this elevation was suppressed by the JNK signaling inhibitor. Our study demonstrated that AA inhibits macrophage viability by inducing S phase cell cycle arrest. The JNK signaling pathway and the downstream FoxO transcription factors are involved in AA-induced RAW264.7 cell cycle arrest.

DNA methyltransferase inhibitor CDA-II inhibits myogenic differentiation

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

Chen, Zirong; Department of Molecular Genetics and Microbiology, Shands Cancer Center, University of Florida, Gainesville, FL 32610; Jin, Guorong

2012-06-08

Highlights: Black-Right-Pointing-Pointer CDA-II inhibits myogenic differentiation in a dose-dependent manner. Black-Right-Pointing-Pointer CDA-II repressed expression of muscle transcription factors and structural proteins. Black-Right-Pointing-Pointer CDA-II inhibited proliferation and migration of C2C12 myoblasts. -- Abstract: CDA-II (cell differentiation agent II), isolated from healthy human urine, is a DNA methyltransferase inhibitor. Previous studies indicated that CDA-II played important roles in the regulation of cell growth and certain differentiation processes. However, it has not been determined whether CDA-II affects skeletal myogenesis. In this study, we investigated effects of CDA-II treatment on skeletal muscle progenitor cell differentiation, migration and proliferation. We found that CDA-II blocked differentiationmore » of murine myoblasts C2C12 in a dose-dependent manner. CDA-II repressed expression of muscle transcription factors, such as Myogenin and Mef2c, and structural proteins, such as myosin heavy chain (Myh3), light chain (Mylpf) and MCK. Moreover, CDA-II inhibited C1C12 cell migration and proliferation. Thus, our data provide the first evidence that CDA-II inhibits growth and differentiation of muscle progenitor cells, suggesting that the use of CDA-II might affect skeletal muscle functions.« less

Solanine induced apoptosis and increased chemosensitivity to Adriamycin in T-cell acute lymphoblastic leukemia cells.

PubMed

Yi, Ying-Jie; Jia, Xiu-Hong; Wang, Jian-Yong; Chen, Jie-Ru; Wang, Hong; Li, You-Jie

2018-05-01

Solanine is an alkaloid and is the main extract of the traditional Chinese herb, Solanum nigrum Linn . It has been reported that Solanine has anti-inflammatory and antitumor properties. The present study aimed to investigate the antitumor effect of Solanine in Jurkat cells and demonstrate the molecular mechanism of antitumor activity of Solanine. A Cell Counting Kit-8 assay demonstrated that Solanine inhibited the proliferation of Jurkat cells in a dose-and time-dependent manner. Cell apoptosis was measured by flow cytometry. Flow cytometry revealed that Solanine induced apoptosis in a dose-dependent manner in Jurkat cells. Reverse transcription-quantitative polymerase chain reaction demonstrated that Solanine modulated the mRNA levels of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax). Additionally, Bcl-2 and Bax expression was measured using western blot analysis. Western blot analysis revealed a significant increase in the expression of Bax and decrease in the expression of Bcl-2. Solanine increased the chemosensitivity of Jurkat cells to Adriamycin. In summary, the present results indicated that the antitumor activity of Solanine was associated with inhibition of cell proliferation, induction of apoptosis and increasing cytotoxicity of Adriamycin. Therefore, Solanine may have potential as a novel agent for the treatment of acute lymphocytic leukemia.

Therapeutic effect of Linum usitatissimum (flaxseed/linseed) fixed oil on acute and chronic arthritic models in albino rats.

PubMed

Kaithwas, Gaurav; Majumdar, Dipak K

2010-06-01

The present study was undertaken to assess the activity/anti-inflammatory potential of Linum usitatissimum fixed oil against castor oil-induced diarrhoea, turpentine oil-induced joint oedema, formaldehyde and Complete Freund's Adjuvant (CFA)-induced arthritis in Wistar albino rats. The oil intraperitoneally, significantly inhibited the castor oil-induced diarrhoea and turpentine oil-induced exudative joint oedema in a dose-dependent manner. Significant inhibitory effect of L. usitatissimum fixed oil was observed in formaldehyde-induced proliferative global oedematous arthritis when given intraperitoneally, with significant checking of the serum glutamic oxaloacetic acid transaminase and serum glutamic pyruvic acid transaminase. Further, L. usitatissimum fixed oil showed a significant dose-dependent protective effect against CFA-induced arthritis as well. Secondary lesions produced by CFA due to a delayed hypersensitivity reaction were also reduced in a significant manner. Anti-inflammatory activity of L. usitatissimum fixed oil can be attributed to the presence of alpha linolenic acid (57.38%, an omega-3 fatty acid, 18:3, n-3) having dual inhibitory effect on arachidonate metabolism resulting in suppressed production of proinflammatory n-6 eicosanoids (PGE(2), LTB(4)) and diminished vascular permeability. These observations suggest possible therapeutic potential of L. usitatissimum fixed oil in inflammatory disorders like rheumatoid arthritis.

Withaferin A modulates the Spindle assembly checkpoint by degradation of Mad2-Cdc20 complex in colorectal cancer cell lines.

PubMed

Das, Tania; Roy, Kumar Singha; Chakrabarti, Tulika; Mukhopadhyay, Sibabrata; Roychoudhury, Susanta

2014-09-01

Withania somnifera L. Dunal (Ashwagandha) is used over centuries in the ayurvedic medicines in India. Withaferin A, a withanolide, is the major compound present in leaf extract of the plant which shows anticancer activity against leukemia, breast cancer and colorectal cancer. It arrests the ovarian cancer cells in the G2/M phase in dose dependent manner. In the current study we show the effect of Withaferin A on cell cycle regulation of colorectal cancer cell lines HCT116 and SW480 and its effect on cell fate. Treatment of these cells with this compound leads to apoptosis in a dose dependent manner. It causes the G2/M arrest in both the cell lines. We show that Withaferin A (WA) causes mitotic delay by blocking Spindle assembly checkpoint (SAC) function. Apoptosis induced by Withaferin A is associated with proteasomal degradation of Mad2 and Cdc20, an important constituent of the Spindle Checkpoint Complex. Further overexpression of Mad2 partially rescues the deleterious effect of WA by restoring proper anaphase initiation and keeping more number of cells viable. We hypothesize that Withaferin A kills cancer cells by delaying the mitotic exit followed by inducing chromosome instability. Copyright © 2014 Elsevier Inc. All rights reserved.

Curcumin inhibits proliferation and induces apoptosis of human colorectal cancer cells by activating the mitochondria apoptotic pathway.

PubMed

Guo, Li-da; Chen, Xue-Jie; Hu, Yu-Hong; Yu, Zhi-Jun; Wang, Duo; Liu, Jing-Ze

2013-03-01

Curcumin, a natural plant extract from Curcuma longa, is known for its anti-carcinogenic and chemopreventive effects on a variety of experimental cancer models. In this study, we evaluated the effects of curcumin and elucidated its mechanism in human colorectal carcinoma cells. Cell viability assay showed that curcumin significantly inhibited the growth of LoVo cells. Curcumin treatment induced the apoptosis accompanied by ultra-structural changes and release of lactate dehydrogenase in a dose-dependent manner. Moreover, treatment with 0-30 µg/mL curcumin decreased the mitochondrial membrane potential and activated the caspase-3 and caspase-9 in a dose- and time-dependent manner. Nuclear and annexin V/PI staining showed that curcumin induced the apoptosis of LoVo cells. FACS analysis revealed that curcumin could induce the cell cycle arrest of LoVo cells at the S phase. Furthermore, western blotting analysis indicated that curcumin induced the release of cytochrome c, a significant increase of Bax and p53 and a marked reduction of Bcl-2 and survivin in LoVo cells. Taken together, our results suggested that curcumin inhibited the growth of LoVo cells by inducing apoptosis through a mitochondria-mediated pathway. Copyright © 2012 John Wiley & Sons, Ltd.

Nonylphenol regulates cyclooxygenase-2 expression via Ros-activated NF-κB pathway in sertoli TM4 cells.

PubMed

Liu, Xiaozhen; Nie, Shaoping; Huang, Danfei; Xie, Mingyong

2015-09-01

The aim of this study was to investigate the signaling pathways involved in the cyclooxygenase (COX)-2 regulation induced by nonylphenol (NP) in mouse testis Sertoli TM4 cells. Our results showed that treatment of TM4 cells with NP increased COX-2 protein expression and interleukin-6 (IL)-6 and prostaglandin E2 (PGE2) secretion in a dose-dependent manner. Pretreatment with reactive oxygen species (ROS) scavenger, N-acetylcysteine (NAC), attenuated NP-induced ROS production, COX-2 expression, and IL-6 and PGE2 release in TM4 cells. Exposure to NP stimulated activation of NF-κB, whereas the NF-κB inhibitor, pyrrolidine dithiocarbamate, attenuated NP-enhanced COX-2 expression and IL-6 and PGE2 release in TM4 cells in a dose-dependent manner. Furthermore, NAC blocked NP-induced activation of NF-κB. In addition, inhibition of COX-2 mitigated NP-induced IL-6 release. In conclusion, NP induced ROS generation, activation of NF-κB pathway, COX-2 upregulation, and IL-6 and PGE2 secretion in TM4 cells. NP may regulate COX-2 expression via ROS-activated NF-κB pathway in Sertoli TM4 cells. © 2014 Wiley Periodicals, Inc.

Annatto Tocotrienol Induces a Cytotoxic Effect on Human Prostate Cancer PC3 Cells via the Simultaneous Inhibition of Src and Stat3.

PubMed

Sugahara, Ryosuke; Sato, Ayami; Uchida, Asuka; Shiozawa, Shinya; Sato, Chiaki; Virgona, Nantiga; Yano, Tomohiro

2015-01-01

Prostate cancer is one of the most frequently occurring cancers and often acquires the potential of androgen-independent growth as a malignant phenotype. Androgen-independent prostate cancer has severe chemoresistance towards conventional chemotherapeutic agents, so a new treatment approach is required for curing such prostate cancer. In this context, the present study was undertaken to check if annatto tocotrienol (main component δ-tocotrienol) could suppress cell growth in human prostate cancer (PC3, androgen-independent type) cells via the inhibition of Src and Stat3. The tocotrienol showed cytotoxic effects on PC3 cells in a dose-dependent manner, and the effect depended on G1 arrest in the cell cycle and subsequent induction of apoptosis. In a cytotoxic dose, the tocotrienol suppressed cellular growth via the simultaneous inhibition of Src and Stat3. Similarly, the treatment combination of both Src and Stat3 inhibitors induced cytotoxic effects in PC3 cells in an additive manner compared to each by itself. With respect to cell cycle regulation and the induction of apoptosis, the combination treatment showed a similar effect to that of the tocotrienol treatment. These results suggest that annatto tocotrienol effectively induces cytotoxicity in androgen-independent prostate cancer cells via the suppression of Src and Stat3.

Evaluation of Antioxidant and DNA Damage Protection Activity of the Hydroalcoholic Extract of Desmostachya bipinnata L. Stapf

PubMed Central

Bhimathati, Solomon Sunder Raj

2014-01-01

Desmostachya bipinnata Stapf (Poaceae/Gramineae) is an official drug of ayurvedic pharmacopoeia. Various parts of this plant were used extensively in traditional and folklore medicine to cure various human ailments. The present study was aimed to evaluate the antioxidant and DNA damage protection activity of hydroalcoholic extract of Desmostachya bipinnata both in vitro and in vivo, to provide scientific basis for traditional usage of this plant. The extract showed significant antioxidant activity in a dose-dependent manner with an IC50 value of 264.18 ± 3.47 μg/mL in H2O2 scavenging assay and prevented the oxidative damage to DNA in presence of DNA damaging agent (Fenton's reagent) at a concentration of 50 μg/mL. Also, the presence of extract protected yeast cells in a dose-dependent manner against DNA damaging agent (Hydroxyurea) in spot assay. Moreover, the presence of extract exhibited significant antioxidant activity in vivo by protecting yeast cells against oxidative stressing agent (H2O2). Altogether, the results of current study revealed that Desmostachya bipinnata is a potential source of antioxidants and lends pharmacological credence to the ethnomedical use of this plant in traditional system of medicine, justifying its therapeutic application for free-radical-induced diseases. PMID:24574873

Evaluation of antioxidant and DNA damage protection activity of the hydroalcoholic extract of Desmostachya bipinnata L. Stapf.

PubMed

Golla, Upendarrao; Bhimathati, Solomon Sunder Raj

2014-01-01

Desmostachya bipinnata Stapf (Poaceae/Gramineae) is an official drug of ayurvedic pharmacopoeia. Various parts of this plant were used extensively in traditional and folklore medicine to cure various human ailments. The present study was aimed to evaluate the antioxidant and DNA damage protection activity of hydroalcoholic extract of Desmostachya bipinnata both in vitro and in vivo, to provide scientific basis for traditional usage of this plant. The extract showed significant antioxidant activity in a dose-dependent manner with an IC50 value of 264.18±3.47  μg/mL in H2O2 scavenging assay and prevented the oxidative damage to DNA in presence of DNA damaging agent (Fenton's reagent) at a concentration of 50  μg/mL. Also, the presence of extract protected yeast cells in a dose-dependent manner against DNA damaging agent (Hydroxyurea) in spot assay. Moreover, the presence of extract exhibited significant antioxidant activity in vivo by protecting yeast cells against oxidative stressing agent (H2O2). Altogether, the results of current study revealed that Desmostachya bipinnata is a potential source of antioxidants and lends pharmacological credence to the ethnomedical use of this plant in traditional system of medicine, justifying its therapeutic application for free-radical-induced diseases.

Effects of Koumine on Adjuvant- and Collagen-Induced Arthritis in Rats.

PubMed

Yang, Jian; Cai, Hong-Da; Zeng, Yu-Lan; Chen, Ze-Hong; Fang, Meng-Han; Su, Yan-Ping; Huang, Hui-Hui; Xu, Ying; Yu, Chang-Xi

2016-10-28

To examine the effect of koumine, a Gelsemium alkaloid, on two experimental models of rheumatoid arthritis (RA), rats with adjuvant-induced arthritis (AIA) and collagen-induced arthritis (CIA) were administered koumine (0.6, 3, or 15 mg/kg/day) or vehicle through gastric gavage (i.g.). Clinical evaluation was performed via measurements of hind paw volume, arthritis index (AI) score, mechanical withdrawal threshold, organ weight, and by radiographic and histological examinations. Levels of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and antitype II collagen (CII) antibody were also examined. In rats with AIA, koumine reduced the AI score and mechanical allodynia of the injected hind paw in a dose-dependent manner and significantly inhibited increase in thymus and liver weights. In rats with CIA, koumine inhibited increase in hind paw volume, AI score, and mechanical allodynia in a dose-dependent manner and reduced joint space narrowing. Furthermore, koumine also attenuated the increase in the expression of IL-1β and TNF-α, as well as the robust increase of serum anti-CII antibodies in response to immunization. These results suggested that koumine effectively attenuated arthritis progression in two rat models of RA and that this therapeutic effect may be associated with its immunoregulatory action.

Drug transport mechanism of oral antidiabetic nanomedicines.

PubMed

Gundogdu, Evren; Yurdasiper, Aysu

2014-01-01

Over the last few decades, extensive efforts have been made worldwide to develop nanomedicine delivery systems, especially via oral route for antidiabetic drugs. Absorption of insulin is hindered by epithelial cells of gastrointestinal tract, acidic gastric pH and digestive enzymes. Recent reports have identified and explained the beneficial role of several structural molecules like mucoadhesive polymers (polyacrylic acid, sodium alginate, chitosan) and other copolymers for the efficient transport and release of insulin to its receptors. Insulin nanomedicines based on alginate-dextran sulfate core with a chitosan-polyethylene glycol-albumin shell reduced glycaemia in a dose dependent manner. Orally available exendin-4 formulations exerted their effects in a time dependent manner. Insulin nanoparticles formed by using alginate and dextran sulfate nucleating around calcium and binding to poloxamer, stabilized by chitosan, and subsequently coated with albumin showed a threefold increase of the hypoglycemic effect in comparison to free insulin in animal models. Solid lipid nanoparticles showed an enhancement of the bioavailability of repaglinide (RG) within optimized solid lipid nanoparticle formulations when compared with RG alone. Nanoparticles represent multiparticulate delivery systems designed to obtain prolonged or controlled drug delivery and to improve bioavailability as well as stability. Nanoparticles can also offer advantages like limiting fluctuations within therapeutic range, reducing side effects, protecting drugs from degradation, decreasing dosing frequency, and improving patient compliance and convenience.

Physcion induces mitochondria-driven apoptosis in colorectal cancer cells via downregulating EMMPRIN.

PubMed

Chen, Xuehong; Gao, Hui; Han, Yantao; Ye, Junli; Xie, Jing; Wang, Chunbo

2015-10-05

Physcion, an anthraquinone derivative widely isolated and characterized from both terrestrial and marine sources, has anti-tumor effects on a variety of carcinoma cells, mainly through inhibition of cell proliferation, apoptosis induction and cell cycle arrest. However, little is known about the mechanisms underlying its role in tumor progression. In the present study, we investigated the molecular mechanisms involved in physcion-induced apoptosis in human colorectal cancer (CRC) lines HCT116. Our results showed that physcion inhibited tumor cell viability in a dose- and time-dependent manner, and induced cell apoptosis via intrinsic mitochondrial pathway. Our results also revealed that physcion treatment significantly inhibited extracelluar matrix metalloproteinase inducer (EMMPRIN) expression in HCT116 cells in a dose-dependent manner and overexpression of EMMPRIN protein markedly reduced physcion-induced cell apoptosis. Furthermore, our results strongly indicated the modulating effect of physcion on EMMPRIN is correlated with AMP-activated protein kinase (AMPK)/Hypoxia-inducible factor 1α (HIF-1α) signaling pathway. Our data provide the first experimental evidence that physcion induces mitochondrial apoptosis in CRC cells by downregulating of EMMPRIN via AMPK/HIF-1α signaling pathway and suggest a new mechanism to explain its anti-tumor effects. Copyright © 2015 Elsevier B.V. All rights reserved.

Attenuated migration by green tea extract (-)-epigallocatechin gallate (EGCG): involvement of 67 kDa laminin receptor internalization in macrophagic cells.

PubMed

Ren, Xuezhi; Guo, Xingzhi; Chen, Li; Guo, Minxia; Peng, Ning; Li, Rui

2014-08-01

Excessive activation of the microglia in the brain is involved in the development of several neurodegenerative diseases. Previous studies have indicated that (-)-epigallocatechin gallate (EGCG), a major active constituent of green tea, exhibits potent suppressive effects on the activation of microglia. As the 67 kDa laminin receptor (67LR) is a key element in cellular activation and migration, we investigated the effect of EGCG on cell migration and 67LR in lipopolysaccharide (LPS)-activated macrophagic RAW264.7 cells. The presence of EGCG (1-25 μM) markedly attenuated LPS-induced cell migration in a dose-dependent manner. However, the total amount of 67LR protein in the RAW264.7 cells was unaffected by EGCG, as revealed by Western blot analysis. In addition, confocal immunofluorescence microscopy indicated that EGCG caused a marked membrane translocation of 67LR from the membrane surface towards the cytoplasm. Cell-surface biotinylation analysis confirmed that EGCG induced a significant internalization of 67LR by 24-68% in a dose-dependent manner. This study helps to explain the pharmacological action of EGCG on 67LR, suggesting its potential use in the treatment of diseases associated with macrophage/microglia activation, such as neurodegenerative diseases and cancer.

X-ray induced alterations in the differentiation and mineralization potential of murine preosteoblastic cells

NASA Astrophysics Data System (ADS)

Hu, Yueyuan; Lau, Patrick; Baumstark-Khan, Christa; Hellweg, Christine E.; Reitz, Günther

2012-05-01

To evaluate the effects of ionizing radiation (IR) on murine preosteoblastic cell differentiation, we directed OCT-1 cells to the osteoblastic lineage by treatment with a combination of β-glycerophosphate (β-GP), ascorbic acid (AA), and dexamethasone (Dex). In vitro mineralization was evaluated based on histochemical staining and quantification of the hydroxyapatite content of the extracellular bone matrix. Expression of mRNA encoding Runx2, transforming growth factor β1 (TGF-β1), osteocalcin (OCN), and p21CDKN1A was analyzed. Exposure to IR reduced the growth rate and diminished cell survival of OCT-1 cells under standard conditions. Notably, calcium content analysis revealed that deposition of mineralized matrix increased significantly under osteogenic conditions after X-ray exposure in a time-dependent manner. In this study, higher radiation doses exert significant overall effects on TGF-β1, OCN, and p21CDKN1A gene expression, suggesting that gene expression following X-ray treatment is affected in a dose-dependent manner. Additionally, we verified that Runx2 was suppressed within 24 h after irradiation at 2 and 4 Gy. Although further studies are required to verify the molecular mechanism, our observations strongly suggest that treatment with IR markedly alters the differentiation and mineralization process of preosteoblastic cells.

Proanthocyanidins from Uncaria rhynchophylla induced apoptosis in MDA-MB-231 breast cancer cells while enhancing cytotoxic effects of 5-fluorouracil.

PubMed

Chen, Xiao-Xin; Leung, George Pak-Heng; Zhang, Zhang-Jin; Xiao, Jian-Bo; Lao, Li-Xing; Feng, Feng; Mak, Judith Choi-Wo; Wang, Ying; Sze, Stephen Cho-Wing; Zhang, Kalin Yan-Bo

2017-09-01

Breast cancer is the most frequently diagnosed cancer and cause of cancer death in women worldwide. Current treatments often result in systematic toxicity and drug resistance. Combinational use of non-toxic phytochemicals with chemotherapeutic agents to enhance the efficacy and reduce toxicity would be one promising approach. In this study, bioactive proanthocyanidins from Uncaria rhynchophylla (UPAs) were isolated and their anti-breast cancer effects alone and in combination with 5- fluorouracil (5-FU) were investigated in MDA-MB-231 breast cancer cells. The results showed that UPAs significantly inhibited cell viability and migration ability in a dose-dependent manner. Moreover, UPAs induced apoptosis in a dose-dependent manner which was associated with increased cellular reactive oxygen species production, loss of mitochondrial membrane potential, increases of Bax/Bcl-2 ratio and levels of cleaved caspase 3. Treatments of the cells with UPAs resulted in an increase in G2/M cell cycle arrest. Cytotoxic effects of 5-FU against MDA-MB-231 cells were enhanced by UPAs. The combination treatment of UPAs and 5-FU for 48 h elicited a synergistic cytotoxic effect on MDA-MB-231 cells. Altogether, these data suggest that UPAs are potential therapeutic agents for breast cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Insights into the mechanism of X-ray-induced disulfide-bond cleavage in lysozyme crystals based on EPR, optical absorption and X-ray diffraction studies

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

Sutton, Kristin A.; Black, Paul J.; Mercer, Kermit R.

2013-12-01

Electron paramagnetic resonance (EPR) and online UV–visible absorption microspectrophotometry with X-ray crystallography have been used in a complementary manner to follow X-ray-induced disulfide-bond cleavage, to confirm a multi-track radiation-damage process and to develop a model of that process. Electron paramagnetic resonance (EPR) and online UV–visible absorption microspectrophotometry with X-ray crystallography have been used in a complementary manner to follow X-ray-induced disulfide-bond cleavage. Online UV–visible spectroscopy showed that upon X-irradiation, disulfide radicalization appeared to saturate at an absorbed dose of approximately 0.5–0.8 MGy, in contrast to the saturating dose of ∼0.2 MGy observed using EPR at much lower dose rates. Themore » observations suggest that a multi-track model involving product formation owing to the interaction of two separate tracks is a valid model for radiation damage in protein crystals. The saturation levels are remarkably consistent given the widely different experimental parameters and the range of total absorbed doses studied. The results indicate that even at the lowest doses used for structural investigations disulfide bonds are already radicalized. Multi-track considerations offer the first step in a comprehensive model of radiation damage that could potentially lead to a combined computational and experimental approach to identifying when damage is likely to be present, to quantitate it and to provide the ability to recover the native unperturbed structure.« less

Immune modulation properties of herbal plant leaves: Phyllanthus niruri aqueous extract on immune cells of tuberculosis patient - in vitro study.

PubMed

Putri, Denise Utami; Rintiswati, Ning; Soesatyo, Marsetyawan Hne; Haryana, Sofia Mubarika

2018-02-01

Disease progression in Tuberculosis (TB) is dependent on host's immune system. Phyllanthus niruri, a traditional herb, has long been used to boost immune system in Indonesian society. This study aimed to observe the potential role of P. niruri in inducing immune cells activity in TB patients by in vitro approach. Peripheral blood mononuclear cells (PBMCs) and macrophages were collected from active pulmonary TB patients. After stimulation with graded doses of P. niruri aqueous extract, cell proliferation, phagocytic activity and nitric oxide (NO) release were analysed. P. niruri aqueous extract induced proliferation of PBMCs, increased NO release, and improved macrophages phagocytic activity. These effects were observed in a dose-dependent manner. This may lead to further research for the potential role of P. niruri as immunomodulatory adjuvant therapy for TB patients.

Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

PubMed

Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

2017-02-01

This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

Dose-dependent effects of theta burst rTMS on cortical excitability and resting-state connectivity of the human motor system.

PubMed

Nettekoven, Charlotte; Volz, Lukas J; Kutscha, Martha; Pool, Eva-Maria; Rehme, Anne K; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

2014-05-14

Theta burst stimulation (TBS), a specific protocol of repetitive transcranial magnetic stimulation (rTMS), induces changes in cortical excitability that last beyond stimulation. TBS-induced aftereffects, however, vary between subjects, and the mechanisms underlying these aftereffects to date remain poorly understood. Therefore, the purpose of this study was to investigate whether increasing the number of pulses of intermittent TBS (iTBS) (1) increases cortical excitability as measured by motor-evoked potentials (MEPs) and (2) alters functional connectivity measured using resting-state fMRI, in a dose-dependent manner. Sixteen healthy, human subjects received three serially applied iTBS blocks of 600 pulses over the primary motor cortex (M1 stimulation) and the parieto-occipital vertex (sham stimulation) to test for dose-dependent iTBS effects on cortical excitability and functional connectivity (four sessions in total). iTBS over M1 increased MEP amplitudes compared with sham stimulation after each stimulation block. Although the increase in MEP amplitudes did not differ between the first and second block of M1 stimulation, we observed a significant increase after three blocks (1800 pulses). Furthermore, iTBS enhanced resting-state functional connectivity between the stimulated M1 and premotor regions in both hemispheres. Functional connectivity between M1 and ipsilateral dorsal premotor cortex further increased dose-dependently after 1800 pulses of iTBS over M1. However, no correlation between changes in MEP amplitudes and functional connectivity was detected. In summary, our data show that increasing the number of iTBS stimulation blocks results in dose-dependent effects at the local level (cortical excitability) as well as at a systems level (functional connectivity) with a dose-dependent enhancement of dorsal premotor cortex-M1 connectivity. Copyright © 2014 the authors 0270-6474/14/346849-11$15.00/0.

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

PubMed Central

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

2008-01-01

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

[Molecular mechanisms of cytoprotective action of the plant proanthocyanidins in gastric lesions].

PubMed

Zaiachkivs'ka, O S

2006-01-01

The molecular defence mechanisms against ethanol- and stress-induced (WRS) gastric lesions under the action of plant proanthocyanidins from grapefruit-seed extract (GSE) were investigated. Pre-treatment with GSE (8-64 mg/kg/day) in dose-dependent manner attenuated gastric lesions induced by 100% ethanol and WRS; the doses of GCE reducing these lesions by 50% (ID50) were 28 and 36 mg/kg/day, respectively and this protective effect was similar to that obtained with PGE2 analogue. Lesions reduction was also accompanied by improvement of gastric blood flow, antiradical action, increased mucosal generation of PGE2, antioxidant activity.

A potential drug interaction between phenobarbital and dolutegravir: A case report.

PubMed

Hikasa, Shinichi; Sawada, Akihiro; Seino, Hitomi; Shimabukuro, Shota; Hideta, Kyoko; Uwa, Noriko; Higasa, Satoshi; Tokugawa, Tazuko; Kimura, Takeshi

2018-06-01

In this report, we describe a human immunodeficiency virus (HIV)-infected patient in whom changes in phenobarbital (PB) dosage resulted in associated changes in plasma concentrations of dolutegravir (DTG). His plasma concentrations of DTG were 0.934, 0.584, 1.003 and 3.25 μg/mL, respectively, with concomitant daily PB doses of 40, 70, 30 and 0 mg, respectively. This case suggests that PB can lead to a remarkable reduction in the plasma concentration of DTG in a dose-dependent manner. Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Inhibition of spicule elongation in sea urchin embryos by the acetylcholinesterase inhibitor eserine.

PubMed

Ohta, Kazumasa; Takahashi, Chifumi; Tosuji, Hiroaki

2009-08-01

The activity of acetylcholinesterase (AchE) increases rapidly after the gastrula stage of sea urchin development. In this report, changes in activity and in the molecular differentiation of AchE were investigated. AchE activity increased slightly during gastrulation and rose sharply thereafter, and was dependent on new RNA synthesis. No activity of butyrylcholinesterase was found. Morphogenesis in sea urchin embryos was inhibited by the AchE inhibitor eserine, which specifically inhibited arm rod formation but not body rod formation. Spicule formation and enzyme activity in cultured micromeres were inhibited by eserine in a dose-dependent manner. During gastrulation, two molecular forms of AchE were detected with polyacrylamide gel electrophoresis. The appearance of an additional band on the gel was consistent with the occurrence of a remarkable increase in the enzyme activity. This additional band appeared as a larger molecular form in Anthocidaris crassispina, Hemicentrotus pulcherrimus, Stomopneustes variolaris, and Strongylocentrotus nudus, and as a smaller form in Clypeaster japonicus and Temnopleurus hardwicki. These results suggest that the change in the molecular form of AchE induced a change in enzymatic activity that in turn may play a role in spicule elongation in sea urchin embryos.

Effect of Salicylate on the Elasticity, Bending Stiffness, and Strength of SOPC Membranes

PubMed Central

Zhou, Yong; Raphael, Robert M.

2005-01-01

Salicylate is a small amphiphilic molecule which has diverse effects on membranes and membrane-mediated processes. We have utilized micropipette aspiration of giant unilamellar vesicles to determine salicylate's effects on lecithin membrane elasticity, bending rigidity, and strength. Salicylate effectively reduces the apparent area compressibility modulus and bending modulus of membranes in a dose-dependent manner at concentrations above 1 mM, but does not greatly alter the actual elastic compressibility modulus at the maximal tested concentration of 10 mM. The effect of salicylate on membrane strength was investigated using dynamic tension spectroscopy, which revealed that salicylate increases the frequency of spontaneous defect formation and lowers the energy barrier for unstable hole formation. The mechanical and dynamic tension experiments are consistent and support a picture in which salicylate disrupts membrane stability by decreasing membrane stiffness and membrane thickness. The tension-dependent partitioning of salicylate was utilized to calculate the molecular volume of salicylate in the membrane. The free energy of transfer for salicylate insertion into the membrane and the corresponding partition coefficient were also estimated, and indicated favorable salicylate-membrane interactions. The mechanical changes induced by salicylate may affect several biological processes, especially those associated with membrane curvature and permeability. PMID:15951377

Thioridazine dose-related effects on biomechanical force platform measures of sway in young and old men.

PubMed

Liu, Y J; Stagni, G; Walden, J G; Shepherd, A M; Lichtenstein, M J

1998-04-01

Thioridazine (TDZ) is associated with an increased risk of falls. The purpose of this study was to determine whether (1) thioridazine increases Biomechanics Force Platform (BFP) measures of sway in a dose-related manner, (2) there is a difference in sway between young and old men, (3) there is a correlation between sway and orthostatic changes in BP and HR. Seven younger (aged 20-42) and five older (aged 70-76) healthy male volunteers received, in a randomized order double-blind design, a single oral dose of 0, 25, and 50 mg of TDZ on three separate days at least 7 days apart and 75 mg on the fourth day of the study. Sway and blood pressure were measured for 24 hours. A general clinical research center. Biomechanics force platform measures of postural sway were measured as the movement of the center of pressure. The elliptical area (EA) and average velocity (AV) were calculated with eyes open and eyes closed. Blood pressure and heart rate were measured for 5 minutes supine and 5 minutes standing. Thioridazine increases BFP sway in a dose-dependent manner. EA increased from 0.56 (SD = .51) cm2 for placebo to 0.88 (SD = 1.09) cm2 for 75 mg TDZ. AV increased from 1.07 (SD = .27) cm/sec, placebo, to 1.43 (SD = .55) cm/sec, 75 mg TDZ. Older men swayed more than younger men. Changes followed the expected time course for TDZ. EA and AV were associated with HR and BP, e.g., SBP versus ln(EA) and ln(AV) (r = -0.21 and r = -0.22, respectively; P < .0001). Thioridazine increases validated measures of fall risk dose dependently in young and old men. This may explain the effects of neuroleptic drugs on fall risk in older people.

Evaluation of the RBC Pig-a and PIGRET assays using single doses of hydroxyurea and melphalan in rats.

PubMed

Adachi, Hideki; Uematsu, Yasuaki; Yamada, Toru

2016-11-15

To evaluate the suitability of the rat Pig-a assay on reticulocytes (PIGRET assay) as a short-term test, red blood cell (RBC) Pig-a and PIGRET assays after single doses with hydroxyurea (HU) and melphalan (L-PAM) were conducted and the results of both assays were compared. HU was administered once orally to male SD rats at 250, 500 and 1000mg/kg, and both assays were conducted using peripheral blood withdrawn from the jugular vein at 1, 2 and 4 weeks after dosing. L-PAM was administered at 1.25, 2.5 and 5mg/kg in the same manner. L-PAM produced significant dose-dependent increases in mutant frequencies in the PIGRET assay after single oral doses, but did not produce dose-dependent increases in mutant frequencies in the RBC Pig-a assay. These results suggest that the PIGRET assay is more sensitive for the evaluation of the mutagenic potential of L-PAM than the RBC Pig-a assay. In contrast, HU, a clastogenic but not DNA-reactive compound, gave negative results in both assays. The results with these 2 chemicals indicate that the single-dose PIGRET assay in rats has the potential to properly detect DNA-reactive compounds that directly cause DNA damage in a short-term assay. Copyright © 2016 Elsevier B.V. All rights reserved.

Can increasing the viscosity of formulations be used to reduce the human skin penetration of the sunscreen oxybenzone?

PubMed

Cross, S E; Jiang, R; Benson, H A; Roberts, M S

2001-07-01

The effect of adding thickening agents on the penetration of a sunscreen benzophenone-3 through epidermal and a high-density polyethylene membrane was studied using both very thick (infinite dose) and thin (in use) applications. Contradictory results were obtained. Thickening agents retard skin penetration, in a manner consistent with a diffusional resistance in the formulation, when applied as an infinite dose. In contrast, when applied as in thin (in use) doses, thickening agents promote penetration, most likely through greater stratum corneum diffusivity arising from an enhanced hydration by the thicker formulations. The two key implications from this work are (i) a recognition of the danger in the potential extrapolation of infinite dosing to in use situations, and (ii) to recognize that thicker formulations may sometimes enhance the penetration of other topical agents when applied "in use".

Peripheral opioid analgesia in teeth with symptomatic inflamed pulps.

PubMed Central

Uhle, R. A.; Reader, A.; Nist, R.; Weaver, J.; Beck, M.; Meyers, W. J.

1997-01-01

The purpose of this study was to investigate the ability of low-dose fentanyl to produce analgesia when administered via the periodontal ligament injection in teeth with symptomatic, inflamed pulps. All subjects presented for emergency treatment with moderate to severe pain and had a posterior tooth with a clinical diagnosis of irreversible pulpitis. Twenty subjects randomly received either 10 micrograms fentanyl citrate or saline placebo via the periodontal ligament injection in a double-blind manner. The subjects rated their pain prior to injection and rated pain intensity and pain half gone for 59 min postinjection. Low-dose fentanyl delivered via the periodontal ligament injection in inflamed teeth provided significantly greater analgesia than the saline placebo (P < 0.05). Since the dose of fentanyl used was less than the dose required to provide analgesia by a central mechanism, the results of this study may be consistent with a peripheral opioid mechanism of action. PMID:9481968

3,3′,4,4′,5-Pentachlorobiphenyl (PCB 126) Decreases Hepatic and Systemic Ratios of Epoxide to Diol Metabolites of Unsaturated Fatty Acids in Male Rats

PubMed Central

Wu, Xianai; Yang, Jun; Morisseau, Christophe; Robertson, Larry W.; Hammock, Bruce; Lehmler, Hans-Joachim

2016-01-01

Disruption of the homeostasis of oxygenated regulatory lipid mediators (oxylipins), potential markers of exposure to aryl hydrocarbon receptor (AhR) agonists, such as 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126), is associated with a range of diseases, including nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Here we test the hypothesis that PCB 126 exposure alters the levels of oxylipins in rats. Male Sprague-Dawley rats (5-weeks old) were treated over a 3-month period every 2 weeks with intraperitoneal injections of PCB 126 in corn oil (cumulative doses of 0, 19.8, 97.8, and 390 µg/kg b.w.; 6 injections total). PCB 126 treatment caused a reduction in growth rates at the highest dose investigated, a dose-dependent decrease in thymus weights, and a dose-dependent increase in liver weights. Liver PCB 126 levels increased in a dose-dependent manner, while levels in plasma were below or close to the detection limit. The ratios of several epoxides to diol metabolites formed via the cytochrome P450 (P450) monooxygenase/soluble epoxide hydrolase (sEH) pathway from polyunsaturated fatty acids displayed a dose-dependent decrease in the liver and plasma, whereas levels of oxylipins formed by other metabolic pathways were generally not altered by PCB 126 treatment. The effects of PCB 126 on epoxide-to-diol ratios were associated with an increased CYP1A activity in liver microsomes and an increased sEH activity in liver cytosol and peroxisomes. These results suggest that oxylipins are potential biomarkers of exposure to PCB 126 and that the P450/sEH pathway is a therapeutic target for PCB 126-mediated hepatotoxicity that warrants further attention. PMID:27208083

Erysodine, a competitive antagonist at neuronal nicotinic acetylcholine receptors, decreases ethanol consumption in alcohol-preferring UChB rats.

PubMed

Quiroz, Gabriel; Guerra-Díaz, Nicolás; Iturriaga-Vásquez, Patricio; Rivera-Meza, Mario; Quintanilla, María Elena; Sotomayor-Zárate, Ramón

2018-09-03

Alcohol abuse is a worldwide health problem with high economic costs to health systems. Emerging evidence suggests that modulation of brain nicotinic acetylcholine receptors (nAChRs) may be a therapeutic target for alcohol dependence. In this work, we assess the effectiveness of four doses of erysodine (1.5, 2.0, 4.0 or 8.0 mg/kg/day, i.p.), a competitive antagonist of nAChRs, on voluntary ethanol consumption behavior in alcohol-preferring UChB rats, administered during three consecutive days. Results show that erysodine administration produces a dose-dependent reduction in ethanol consumption respect to saline injection (control group). The highest doses of erysodine (4 and 8 mg/kg) reduce (45 and 66%, respectively) the ethanol intake during treatment period and first day of post-treatment compared to control group. While, the lowest doses of erysodine (1.5 and 2 mg/kg) only reduce ethanol intake during one day of treatment period. These effective reductions in ethanol intake were 23 and 29% for 1.5 and 2 mg/kg erysodine, respectively. Locomotor activity induced by a high dose of erysodine (10 mg/kg) was similar to those observed with saline injection in control rats, showing that the reduction in ethanol intake was not produced by hypolocomotor effect induced by erysodine. This is the first report showing that erysodine reduces ethanol intake in UChB rats in a dose-dependent manner. Our results highlight the role of nAChRs in the reward effects of ethanol and its modulation as a potentially effective pharmacological alternative for alcohol dependence treatment. Copyright © 2018 Elsevier B.V. All rights reserved.

Curcumin Attenuates Opioid Tolerance and Dependence by Inhibiting Ca2+/Calmodulin-Dependent Protein Kinase II α Activity

PubMed Central

Hu, Xiaoyu; Huang, Fang; Szymusiak, Magdalena

2015-01-01

Chronic use of opioid analgesics has been hindered by the development of opioid addiction and tolerance. We have reported that curcumin, a natural flavonoid from the rhizome of Curcuma longa, attenuated opioid tolerance, although the underlying mechanism remains unclear. In this study, we tested the hypothesis that curcumin may inhibit Ca2+/calmodulin-dependent protein kinase II α (CaMKIIα), a protein kinase that has been previously proposed to be critical for opioid tolerance and dependence. In this study, we used state-of-the-art polymeric formulation technology to produce poly(lactic-co-glycolic acid) (PLGA)-curcumin nanoparticles (nanocurcumin) to overcome the drug’s poor solubility and bioavailability, which has made it extremely difficult for studying in vivo pharmacological actions of curcumin. We found that PLGA-curcumin nanoparticles reduced the dose requirement by 11- to 33-fold. Pretreatment with PLGA-curcumin (by mouth) prevented the development of opioid tolerance and dependence in a dose-dependent manner, with ED50 values of 3.9 and 3.2 mg/kg, respectively. PLGA-curcumin dose-dependently attenuated already-established opioid tolerance (ED50 = 12.6 mg/kg p.o.) and dependence (ED50 = 3.1 mg/kg p.o.). Curcumin or PLGA-curcumin did not produce antinociception by itself or affect morphine (1–10 mg/kg) antinociception. Moreover, we found that the behavioral effects of curcumin on opioid tolerance and dependence correlated with its inhibition of morphine-induced CaMKIIα activation in the brain. These results suggest that curcumin may attenuate opioid tolerance and dependence by suppressing CaMKIIα activity. PMID:25515789

Hepatitis C Virus Induces Regulatory T Cells by Naturally Occurring Viral Variants to Suppress T Cell Responses

PubMed Central

Cusick, Matthew F.; Schiller, Jennifer J.; Gill, Joan C.; Eckels, David D.

2011-01-01

Regulatory T cell markers are increased in chronically infected individuals with the hepatitis C virus (HCV), but to date, the induction and maintenance of Tregs in HCV infection has not been clearly defined. In this paper, we demonstrate that naturally occurring viral variants suppress T cell responses to cognate NS3358-375 in an antigen-specific manner. Of four archetypal variants, S370P induced regulatory T cell markers in comparison to NS3358-375-stimulated CD4 T cells. Further, the addition of variant-specific CD4 T cells back into a polyclonal culture in a dose-dependent manner inhibited the T cell response. These results suggest that HCV is able to induce antigen-specific regulatory T cells to suppress the antiviral T cell response in an antigen-specific manner, thus contributing to a niche within the host that could be conducive to HCV persistence. PMID:21197453

Thrombin-induced p38 mitogen-activated protein kinase activation is mediated by epidermal growth factor receptor transactivation pathway

PubMed Central

Kanda, Yasunari; Mizuno, Katsushige; Kuroki, Yasutomi; Watanabe, Yasuhiro

2001-01-01

Thrombin is a potent mitogen for vascular smooth muscle cells (VSMC) and has been implicated its pathogenic role in vascular remodelling. However, the signalling pathways by which thrombin mediates its mitogenic response are not fully understood.We have previously reported that thrombin activates p38 mitogen-activated protein kinase (p38 MAPK) by a tyrosine kinase-dependent mechanism, and that p38 MAPK has a role in thrombin-induced mitogenic response in rat VSMC.In the present study, we examine the involvement of epidermal growth factor (EGF) receptor in thrombin-induced p38 MAPK activation. We found that thrombin induced EGF receptor tyrosine phosphorylation (transactivation) in A10 cells, a clonal VSMC cell line. A selective inhibitor of EGF receptor kinase (AG1478) inhibited the p38 MAPK activation in a dose-dependent manner, whereas it had no effect on the response to platelet-derived growth factor (PDGF). EGF receptor phosphorylation induced by thrombin was inhibited by BAPTA-AM and GF109203X, which suggest a requirement for intracellular Ca2+ increase and protein kinase C.We next examined the effect of AG1478 on thrombin-induced DNA synthesis. AG1478 inhibited thrombin-induced DNA synthesis in a dose-dependent manner. In contrast, PDGF-induced DNA synthesis was not affected by AG1478.In conclusion, these data suggest that the EGF receptor transactivation and subsequent p38 MAPK activation is required for thrombin-induced proliferation of VSMC. PMID:11309236

Anti-inflammatory activity of methylene chloride fraction from Glehnia littoralis extract via suppression of NF-kappa B and mitogen-activated protein kinase activity.

PubMed

Yoon, Taesook; Cheon, Myeong Sook; Lee, A Yeong; Lee, Do Yeon; Moon, Byeong Cheol; Chun, Jin Mi; Choo, Byung Kil; Kim, Ho Kyoung

2010-01-01

Glehnia littoralis (Umbelliferae) has been used traditionally in Korean, Japanese, and Chinese medicine for the treatment of immune-related diseases; however, its anti-inflammatory activity and underlying mechanism remain to be defined. We investigated the anti-inflammatory effect and inhibitory mechanism on inflammation by the methylene chloride fraction from Glehnia littoralis extract (MCF-GLE), which was more effective than Glehnia littoralis extract (GLE). MCF-GLE inhibited 12-O-Tetradecanoyl-phorbol-13-acetate (TPA)-induced inflammation in an inflammatory edema mouse model. Also, MCF-GLE strongly inhibited the releases of nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) and significantly suppressed the mRNA and protein expression of inducible nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-stimulated RAW 264.7 macrophage cells in a dose-dependent manner. Furthermore, MCF-GLE suppressed NF-kappaB activation and IkappaB-alpha degradation. MCF-GLE also attenuated the activation of ERK and JNK in a dose-dependent manner. These results indicate that MCF-GLE has an inhibitory effect on the in vivo and in vitro inflammatory reaction and is a possible therapeutic agent. Our results suggest that the anti-inflammatory properties of MCF-GLE may result from the inhibition of pro-inflammatory mediators, such as NO, PGE(2), TNF-alpha, and IL-1beta via suppression of NF-kappaB- and mitogen-activated protein kinases-dependent pathways.

Ox-LDL Promotes Migration and Adhesion of Bone Marrow-Derived Mesenchymal Stem Cells via Regulation of MCP-1 Expression

PubMed Central

Wang, Congrui; Wang, Huaibin; Lu, Ming; Li, Yonghai; Feng, Huigen; Yuan, Zhiqing

2013-01-01

Bone marrow-derived mesenchymal stem cells (bmMSCs) are the most important cell source for stem cell transplant therapy. The migration capacity of MSCs is one of the determinants of the efficiency of MSC-based transplant therapy. Our recent study has shown that low concentrations of oxidized low-density lipoprotein (ox-LDL) can stimulate proliferation of bmMSCs. In this study, we investigated the effects of ox-LDL on bmMSC migration and adhesion, as well as the related mechanisms. Our results show that transmigration rates of bmMSCs and cell-cell adhesion between bmMSCs and monocytes are significantly increased by treatments with ox-LDL in a dose- and time-dependent manner. Expressions of ICAM-1, PECAM-1, and VCAM-1 as well as the levels of intracellular Ca2+ are also markedly increased by ox-LDL in a dose-dependent manner. Cytoskeleton analysis shows that ox-LDL treatment benefits to spreading of bmMSCs and organization of F-actin fibers after being plated for 6 hours. More interestingly, treatments with ox-LDL also markedly increase expressions of LOX-1, MCP-1, and TGF-β; however, LOX-1 antibody and MCP-1 shRNA markedly inhibit ox-LDL-induced migration and adhesion of bmMSCs, which suggests that ox-LDL-induced bmMSC migration and adhesion are dependent on LOX-1 activation and MCP-1 expression. PMID:23956504

Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar

USGS Publications Warehouse

Duffy, Tara A.; Iwanowicz, Luke R.; McCormick, Stephen D.

2014-01-01

Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (four day) exposures using three doses each of 17α-ethinylestradiol (EE2), 17β-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and one year old smolts. Differential response was compared using vitellogenin (Vtg, a precursor egg protein) gene transcription. Smolts were also examined for impacts on plasma Vtg, cortisol, thyroid hormones (T4/T3) and hepatosomatic index (HSI). Compound-related mortality was not observed in any life stage, but Vtg mRNA was elevated in a dose-dependent manner in yolk-sac larvae, fry and smolts but not in embyos. The estrogens EE2 and E2 were consistently stronger inducers of Vtg than NP. Embryos responded significantly to the highest concentration of EE2 only, while older life stages responded to the highest doses of all three compounds, as well as intermediate doses of EE2 and E2. Maximal transcription was greater for fry among the three earliest life stages, suggesting fry may be the most responsive life stage in early development. Smolt plasma Vtg was also significantly increased, and this response was observed at lower doses of each compound than was detected by gene transcription suggesting this is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2 and plasma T3 decreased at the highest dose of EE2. Our results indicate that all life stages after hatching are potentially sensitive to endocrine disruption by estrogenic compounds and that physiological responses were altered over a short window of exposure, indicating the potential for these compounds to impact fish in the wild.

Role of stresses in annealing of ion-implantation damage in Si

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

Seshan, K.; EerNisse, E.P.

Recent results showing a crystallographic orientation dependence of growth kinetics, secondary defects, and stress relief in annealing of ion-implanted Si are shown to be self-consistent if interpreted in terms of the influence of stresses upon annealing processes. The stress influence proposed is microplastic shear which is induced in (112) directions on (111) planes inclined to the implant surface by the biaxial stress created in the implant region by ion-implantation damage. The shear stresses are shown to be dependent on crystallographic orientation in a manner consistent with the model.

Targeting of Antithrombin in Hemophilia A or B with RNAi Therapy.

PubMed

Pasi, K John; Rangarajan, Savita; Georgiev, Pencho; Mant, Tim; Creagh, Michael D; Lissitchkov, Toshko; Bevan, David; Austin, Steve; Hay, Charles R; Hegemann, Inga; Kazmi, Rashid; Chowdary, Pratima; Gercheva-Kyuchukova, Liana; Mamonov, Vasily; Timofeeva, Margarita; Soh, Chang-Heok; Garg, Pushkal; Vaishnaw, Akshay; Akinc, Akin; Sørensen, Benny; Ragni, Margaret V

2017-08-31

Current hemophilia treatment involves frequent intravenous infusions of clotting factors, which is associated with variable hemostatic protection, a high treatment burden, and a risk of the development of inhibitory alloantibodies. Fitusiran, an investigational RNA interference (RNAi) therapy that targets antithrombin (encoded by SERPINC1), is in development to address these and other limitations. In this phase 1 dose-escalation study, we enrolled 4 healthy volunteers and 25 participants with moderate or severe hemophilia A or B who did not have inhibitory alloantibodies. Healthy volunteers received a single subcutaneous injection of fitusiran (at a dose of 0.03 mg per kilogram of body weight) or placebo. The participants with hemophilia received three injections of fitusiran administered either once weekly (at a dose of 0.015, 0.045, or 0.075 mg per kilogram) or once monthly (at a dose of 0.225, 0.45, 0.9, or 1.8 mg per kilogram or a fixed dose of 80 mg). The study objectives were to assess the pharmacokinetic and pharmacodynamic characteristics and safety of fitusiran. No thromboembolic events were observed during the study. The most common adverse events were mild injection-site reactions. Plasma levels of fitusiran increased in a dose-dependent manner and showed no accumulation with repeated administration. The monthly regimen induced a dose-dependent mean maximum antithrombin reduction of 70 to 89% from baseline. A reduction in the antithrombin level of more than 75% from baseline resulted in median peak thrombin values at the lower end of the range observed in healthy participants. Once-monthly subcutaneous administration of fitusiran resulted in dose-dependent lowering of the antithrombin level and increased thrombin generation in participants with hemophilia A or B who did not have inhibitory alloantibodies. (Funded by Alnylam Pharmaceuticals; ClinicalTrials.gov number, NCT02035605 .).

Characterization of Changes in Gene Expression and Biochemical Pathways at Low Levels of Benzene Exposure

PubMed Central

Thomas, Reuben; Hubbard, Alan E.; McHale, Cliona M.; Zhang, Luoping; Rappaport, Stephen M.; Lan, Qing; Rothman, Nathaniel; Vermeulen, Roel; Guyton, Kathryn Z.; Jinot, Jennifer; Sonawane, Babasaheb R.; Smith, Martyn T.

2014-01-01

Benzene, a ubiquitous environmental pollutant, causes acute myeloid leukemia (AML). Recently, through transcriptome profiling of peripheral blood mononuclear cells (PBMC), we reported dose-dependent effects of benzene exposure on gene expression and biochemical pathways in 83 workers exposed across four airborne concentration ranges (from <1 ppm to >10 ppm) compared with 42 subjects with non-workplace ambient exposure levels. Here, we further characterize these dose-dependent effects with continuous benzene exposure in all 125 study subjects. We estimated air benzene exposure levels in the 42 environmentally-exposed subjects from their unmetabolized urinary benzene levels. We used a novel non-parametric, data-adaptive model selection method to estimate the change with dose in the expression of each gene. We describe non-parametric approaches to model pathway responses and used these to estimate the dose responses of the AML pathway and 4 other pathways of interest. The response patterns of majority of genes as captured by mean estimates of the first and second principal components of the dose-response for the five pathways and the profiles of 6 AML pathway response-representative genes (identified by clustering) exhibited similar apparent supra-linear responses. Responses at or below 0.1 ppm benzene were observed for altered expression of AML pathway genes and CYP2E1. Together, these data show that benzene alters disease-relevant pathways and genes in a dose-dependent manner, with effects apparent at doses as low as 100 ppb in air. Studies with extensive exposure assessment of subjects exposed in the low-dose range between 10 ppb and 1 ppm are needed to confirm these findings. PMID:24786086

Ocular allergy modulation to hi-dose antigen sensitization is a Treg-dependent process.

PubMed

Lee, Hyun Soo; Schlereth, Simona; Khandelwal, Payal; Saban, Daniel R

2013-01-01

A reproducible method to inhibit allergic immune responses is accomplished with hi-dose Ag sensitization, via intraperitoneal (IP) injection. However, the role of CD4+ CD25+ FoxP3+ T regulatory cells (Treg) in this process is unknown, as is whether such modulation extends to ocular allergy. We therefore determined herein whether hi-dose sensitization modulates ocular allergy, and whether CD4+ CD25+ FoxP3+ Treg are involved. C57BL/6 mice were IP sensitized via low-dose (100 µg) versus hi-dose (1000 µg) ovalbumin (OVA), in aluminum hydroxide (1 mg) and pertussis-toxin (300 ng). Other mice received anti-CD25 Ab (PC61) to ablate Treg during sensitization. In another experiment, Treg from hi-dose sensitized mice were adoptively transferred into low-dose sensitized mice. Once daily OVA challenges were administered. Clinical signs, IgE, T cell cytokines, and eosinophils were assessed. Data revealed that hi-dose, but not low-dose, sensitization led to allergy modulation, indicated by decreased clinical signs, serum IgE levels, Th2 recall responses, and eosinophil recruitment. T cells from hi-dose sensitized mice showed a robust increase in TGF-b production, and Treg from these mice were able to efficiently suppress effector T cell proliferation in vitro. In addition, in vivo Treg ablation in hi-dose sensitized mice revoked allergy modulation. Lastly, Treg from hi-dose sensitized mice were able to adoptively transfer allergy modulation to their low-dose sensitized counterparts. Collectively, these findings indicate that modulation to hi-dose sensitization, which is extended to ocular allergy, occurs in a Treg-dependent manner. In addition, our data suggest that hi-dose sensitization may henceforth facilitate the further examination of CD4+ CD25+ FoxP3+ Treg in allergic disease.

Characterizing regional-scale temporal evolution of air dose rates after the Fukushima Daiichi Nuclear Power Plant accident.

PubMed

Wainwright, Haruko M; Seki, Akiyuki; Mikami, Satoshi; Saito, Kimiaki

2018-09-01

In this study, we quantify the temporal changes of air dose rates in the regional scale around the Fukushima Dai-ichi Nuclear Power Plant in Japan, and predict the spatial distribution of air dose rates in the future. We first apply the Bayesian geostatistical method developed by Wainwright et al. (2017) to integrate multiscale datasets including ground-based walk and car surveys, and airborne surveys, all of which have different scales, resolutions, spatial coverage, and accuracy. This method is based on geostatistics to represent spatial heterogeneous structures, and also on Bayesian hierarchical models to integrate multiscale, multi-type datasets in a consistent manner. We apply this method to the datasets from three years: 2014 to 2016. The temporal changes among the three integrated maps enables us to characterize the spatiotemporal dynamics of radiation air dose rates. The data-driven ecological decay model is then coupled with the integrated map to predict future dose rates. Results show that the air dose rates are decreasing consistently across the region. While slower in the forested region, the decrease is particularly significant in the town area. The decontamination has contributed to significant reduction of air dose rates. By 2026, the air dose rates will continue to decrease, and the area above 3.8 μSv/h will be almost fully contained within the non-residential forested zone. Copyright © 2018 Elsevier Ltd. All rights reserved.

Extracellular Alkalinization as a Defense Response in Potato Cells.

PubMed

Moroz, Natalia; Fritch, Karen R; Marcec, Matthew J; Tripathi, Diwaker; Smertenko, Andrei; Tanaka, Kiwamu

2017-01-01

A quantitative and robust bioassay to assess plant defense response is important for studies of disease resistance and also for the early identification of disease during pre- or non-symptomatic phases. An increase in extracellular pH is known to be an early defense response in plants. In this study, we demonstrate extracellular alkalinization as a defense response in potatoes. Using potato suspension cell cultures, we observed an alkalinization response against various pathogen- and plant-derived elicitors in a dose- and time-dependent manner. We also assessed the defense response against a variety of potato pathogens, such as protists ( Phytophthora infestans and Spongospora subterranea ) and fungi ( Verticillium dahliae and Colletotrichum coccodes ). Our results show that extracellular pH increases within 30 min in proportion to the number of pathogen spores added. Consistently with the alkalinization effect, the higher transcription level of several defense-related genes and production of reactive oxygen species was observed. Our results demonstrate that the alkalinization response is an effective marker to study early stages of defense response in potatoes.

Characteristics and Antitumor Activity of Morchella esculenta Polysaccharide Extracted by Pulsed Electric Field

PubMed Central

Liu, Chao; Sun, Yonghai; Mao, Qian; Guo, Xiaolei; Li, Peng; Liu, Yang; Xu, Na

2016-01-01

Polysaccharides from Morchella esculenta have been proven to be functional and helpful for humans. The purpose of this study was to investigate the chemical structure and anti-proliferating and antitumor activities of a Morchella esculenta polysaccharide (MEP) extracted by pulsed electric field (PEF) in submerged fermentation. The endo-polysaccharide was separated and purified by column chromatography and Gel permeation chromatography, and analyzed by gas chromatography. The MEP with an average molecular weight of 81,835 Da consisted of xylose, glucose, mannose, rhamnose and galactose at the ratio of 5.4:5.0:6.5:7.8:72.3. Structure of MEP was further analyzed by Fourier-transform infrared spectroscopy and 1H and 13C liquid-state nuclear magnetic resonance spectroscopy. Apoptosis tests proved that MEP could inhibit the proliferation and growth of human colon cancer HT-29 cells in a time- and dose-dependent manner within 48 h. This study provides more information on chemical structure of anti-proliferating polysaccharides isolated from Morchella esculenta. PMID:27338370

Selective cytotoxic effect of non-thermal micro-DBD plasma

NASA Astrophysics Data System (ADS)

Kwon, Byung-Su; Choi, Eun Ha; Chang, Boksoon; Choi, Jeong-Hyun; Kim, Kyung Sook; Park, Hun-Kuk

2016-10-01

Non-thermal plasma has been extensively researched as a new cancer treatment technology. We investigated the selective cytotoxic effects of non-thermal micro-dielectric barrier discharge (micro-DBD) plasma in cervical cancer cells. Two human cervical cancer cell lines (HeLa and SiHa) and one human fibroblast (HFB) cell line were treated with micro-DBD plasma. All cells underwent apoptotic death induced by plasma in a dose-dependent manner. The plasma showed selective inhibition of cell proliferation in cervical cancer cells compared to HFBs. The selective effects of the plasma were also observed between the different cervical cancer cell lines. Plasma treatment significantly inhibited the proliferation of SiHa cells in comparison to HeLa cells. The changes in gene expression were significant in the cervical cancer cells in comparison to HFBs. Among the cancer cells, apoptosis-related genes were significantly enriched in SiHa cells. These changes were consistent with the differential cytotoxic effects observed in different cell lines.

Structure and in vitro anticancer activity of sulfated O-polysaccharide from marine bacterium Poseidonocella pacifica KMM 9010T.

PubMed

Kokoulin, Maxim S; Kuzmich, Alexandra S; Kalinovsky, Anatoly I; Rubtsov, Eugene S; Romanenko, Lyudmila A; Mikhailov, Valery V; Komandrova, Nadezhda A

2017-12-15

We presented the structure of the sulfated polysaccharide moiety and anticancer activity in vitro of the О-deacylated lipopolysaccharide (DPS) isolated from the marine bacterium Poseidonocella pacifica KMM 9010 T . The structure of O-polysaccharide was investigated by chemical methods along with 1 H and 13 C NMR spectroscopy. The O-polysaccharide was built up of sulfated disaccharide repeating units consisted of d-rhamnose (d-Rhaр) and 3-deoxy-d-manno-oct-2-ulosonic acid (Kdop): →7)-β-Kdoр4Ac5S-(2→3)-β-d-Rhaр2S-(1→. We demonstrated that the DPS from P. pacifica KMM 9010 T non-toxic for normal mouse epidermal cells (JB6 Cl41 cell line) and inhibited colony formation of human colorectal carcinoma HT-29, breast adenocarcinoma MCF-7 and melanoma SK-MEL-5 cells in a dose-dependent manner. Copyright © 2017 Elsevier Ltd. All rights reserved.

Role of Berberine in the Treatment of Methicillin-Resistant Staphylococcus aureus Infections

NASA Astrophysics Data System (ADS)

Chu, Ming; Zhang, Ming-Bo; Liu, Yan-Chen; Kang, Jia-Rui; Chu, Zheng-Yun; Yin, Kai-Lin; Ding, Ling-Yu; Ding, Ran; Xiao, Rong-Xin; Yin, Yi-Nan; Liu, Xiao-Yan; Wang, Yue-Dan

2016-04-01

Berberine is an isoquinoline alkaloid widely used in the treatment of microbial infections. Recent studies have shown that berberine can enhance the inhibitory efficacy of antibiotics against clinical multi-drug resistant isolates of methicillin-resistant Staphylococcus aureus (MRSA). However, the underlying mechanisms are poorly understood. Here, we demonstrated that sub-minimum inhibitory concentrations (MICs) of berberine exhibited no bactericidal activity against MRSA, but affected MRSA biofilm development in a dose dependent manner within the concentration ranging from 1 to 64 μg/mL. Further study indicated that berberine inhibited MRSA amyloid fibrils formation, which consist of phenol-soluble modulins (PSMs). Molecular dynamics simulation revealed that berberine could bind with the phenyl ring of Phe19 in PSMα2 through hydrophobic interaction. Collectively, berberine can inhibit MRSA biofilm formation via affecting PSMs’ aggregation into amyloid fibrils, and thereby enhance bactericidal activity of antibiotics. These findings will provide new insights into the multiple pharmacological properties of berberine in the treatment of microbial-generated amyloid involved diseases.

Nucleopolyhedroviruses (NPV) induce the expression of small heat shock protein 25.4 in Antheraea pernyi.

PubMed

Zhang, Congfen; Zhu, Baojian; Dai, Li Shang; Liu, Chaoliang; Luo, Xuegang

2016-10-15

Nucleopolyhedroviruses (NPVs) is one group of Baculoviruses. The infection of NPV in silkworm is often lethal. To investigate the effective measures to stop the infection of NPV, we cloned cDNA encoding small heat shock protein 25.4 in Antheraea pernyi (Ap-HSP25.4). The translated amino acid sequence consisted of 223 residues with a calculated molecular mass of 25.4kDa and an isoelectronic point (pI) of 4.93. Quantitative real-time PCR was used to investigate the expression patterns and distribution profiles of Ap-sHSP25.4 before and after challenged with NPV. We found that the inhibitors of eicosanoid synthesis could suppress the transcription of Ap-sHSP25.4 in the fat body in a dose dependent manner. And arachidonic acid induced the expression of Ap-sHSP25.4. Thus, we concluded that sHSPs may be promising candidates to boost insect immunity in practice. Copyright © 2016 Elsevier B.V. All rights reserved.

Prior pregnancy and antenatal rubella sero-negativity-evidence of persistent maternal immunologic alteration?

PubMed

Lao, Terence T; Hui, Annie S Y; Sahota, Daljit S

2017-09-01

It is unclear if the immunologic alterations induced by pregnancy could persist. Antenatal rubella sero-negativity was correlated with gravidity, abortions and parity in 112 083 gravidae managed during 1997-2015, with further analysis stratified for factors known to influence rubella serology. The 10.2% sero-negative gravidae had different characteristics, and the incidence showed significant difference and positive trend (P<.001 for both) with gravidity, abortions and parity. The pattern remained consistent when analysis was stratified for advanced age, high body mass index and medical history, but was negated by hepatitis B virus infection except for abortions, and by high body mass index for parity. For gravidity 2-4, no difference in rubella sero-negativity was found between gravidae with all previous pregnancies ended in abortion vs delivery. Prior pregnancies diminished rubella immunity in a dose-dependent manner, which may be a reflection of the cumulative effect of pregnancy-associated maternal immunologic alteration. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Apigenin Attenuates Melanoma Cell Migration by Inducing Anoikis through Integrin and Focal Adhesion Kinase Inhibition.

PubMed

Hasnat, Md Abul; Pervin, Mehnaz; Lim, Ji Hong; Lim, Beong Ou

2015-11-27

Apigenin, a nonmutagenic flavonoid, has been found to have antitumor properties and is therefore particularly relevant for the development of chemotherapeutic agents for cancers. In this study, time- and dose-dependent cell viability and cytotoxicity were assessed to determine the effects of apigenin on A2058 and A375 melanoma cells. Melanoma cells were pretreated with different concentrations of apigenin and analyzed for morphological changes, anoikis induction, cell migration, and levels of proteins associated with apoptosis. Apigenin reduced integrin protein levels and inhibited the phosphorylation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK1/2), which induce anoikis in human cutaneous melanoma cells. Apigenin exhibited dose-dependent inhibition of melanoma cell migration, unlike untreated controls. Furthermore, apigenin treatment increased apoptotic factors such as caspase-3 and cleaved poly(ADP-ribose) polymerase in a dose-dependent manner, demonstrating the metastasis of melanoma cells. Our results provide a new insight into the mechanisms by which apigenin prevents melanoma metastasis by sensitizing anoikis induced by the loss of integrin proteins in the FAK/ERK1/2 signaling pathway. These findings elucidate the related mechanisms and suggest the potential of apigenin in developing clinical treatment strategies against malignant melanoma.

Effect of dexamethasone on expression of glucocorticoid receptor in human monocyte cell line THP-1.

PubMed

Li, Bo; Bai, Xiangjun; Wanh, Haiping

2006-01-01

The effect of dexamethasone with different concentrations and different stimulating periods on the expression of glucocorticoid receptors (GRalpha, GRbeta) protein was investigated in human monocyte cell line THP-1. The cultured human monocyte line THP-1 cells were stimulated by dexamethasone with different concentrations and different periods. The expression of GRalpha and GRbeta protein was detected by Western blotting. The results showed that the expression of GRalpha and GRbeta was detected in the THP-1 cells. The quantity of GRalpha expression was reduced by dexamethasone under the same concentration with the prolongation of the stimulating periods. The quantity of GRbeta expression was increased by dexamethasone treatment in a time- and dose-dependent manner. It was concluded that dexamethasone stimulation time-dependently reduced the GRalpha expression in THP-1 cells. Dexamethasone stimulation time- and dose-dependently increased the GRbeta expression in THP-1 cells. The expression of GRalpha and GRbeta was regulated by glucocorticoid.

Hormonal regulation of phosphatidylcholine synthesis by reversible modulation of cytidylyltransferase.

PubMed Central

Kelly, K L; Gutierrez, G; Martin, A

1988-01-01

The effect of both lipolytic and antilipolytic hormones on the turnover of phosphatidylcholine in freshly isolated rat adipocytes was investigated. Treatment of adipocytes with agonists such as glucagon or isoprenaline that stimulate lipolysis through a cyclic AMP-dependent mechanism caused an increase in the incorporation of [Me-3H]choline into phosphatidylcholine. Pulse-chase studies indicated that the stimulation was due to an increase in the conversion of choline into phosphatidylcholine, which was both time- and dose-dependent. The stimulatory effect of isoprenaline was inhibited in a dose-dependent manner by oxytocin or insulin. Oxytocin inhibited the incorporation of [Me-3H]choline into phosphatidylcholine in both the presence and the absence of isoprenaline, whereas in the absence of isoprenaline insulin increased the incorporation of [Me-3H]choline into phosphatidylcholine. The effects of isoprenaline, oxytocin and insulin on the incorporation of [3H]choline into phosphatidylcholine were paralleled by changes in the activity of CTP:phosphocholine cytidylyltransferase. PMID:2849424

Effect of advanced glycosylation end products (AGEs) on proliferation of human bone marrow mesenchymal stem cells (MSCs) in vitro.

PubMed

Lu, Yi-Qun; Lu, Yan; Li, Hui-Juan; Cheng, Xing-Bo

2012-10-01

This study aims to explore the effect of advanced glycosylation end products (AGEs) on proliferation of human bone marrow mesenchymal stem cells in vitro and the underlying mechanism. Bone marrow cell proliferation was determined by WST-8 assay using Cell Counting Kit-8 under the intervention of AGEs. In addition, the content of maldondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were also measured. The proliferation activity of mesenchymal stem cells (MSCs) was significantly inhibited when AGEs were added to culture medium, and this effect was dose-dependent and time-dependent. As the concentration of AGEs-bovine serum albumin increased, the content of intracellular MDA was significantly increased, but the activity of SOD in cell homogenates was significantly suppressed, which also showed a dose-dependent manner. AGEs could significantly inhibit the proliferation of MSCs in vitro by improving the oxidative stress in MSCs and breaking the homeostasis of intracellular environment.

Analgesic activity of Nelsonia canescens (Lam.) Spreng.root in albino rats

PubMed Central

Mohaddesi, Behzad; Dwivedi, Ravindra; Ashok, B. K.; Aghera, Hetal; Acharya, Rabinarayan; Shukla, V. J.

2013-01-01

Present study was undertaken to evaluate analgesic activity of root of Nelsonia canescens (Lam.) Spreng, a folklore medicinal plant used as the one of the source plant of Rasna. Study was carried out at two dose levels (270 mg/kg and 540 mg/kg) in albino rats. Analgesic activity was evaluated in formalin induced paw licking, and tail flick methods whereas indomethacin and pentazocine were used as standard analgesic drugs, respectively. At both the dose levels, test drug non-significantly decreased paw licking response at both time intervals. In tail flick model, the administration of the test drug increased pain threshold response in a dose dependent manner. In therapeutically equivalent dose level, analgesic activity was observed only after 180 min while in TED ×2 treated group analgesia was observed at 30 min and lasted even up to 240 min. The results suggested that N.canescens root possess moderate analgesic activity. PMID:24250136

Antiviral effects of Stichopus japonicus acid mucopolysaccharide on hepatitis B virus transgenic mice

NASA Astrophysics Data System (ADS)

Xin, Yongning; Li, Wei; Lu, Linlin; Zhou, Li; Victor, David W.; Xuan, Shiying

2016-08-01

Hepatitis B virus (HBV) is a significant global pathogen and efficient cure for HBV patients is still a challenging goal. We previously reported that acidic mucopolysaccharide from stichopus japonicus selenka (SJAMP) could inhibit HBsAg and HBeAg expression in vitro. However, the potential anti-HBV effects of SJAMP in vivo have not yet been explored. In this study, we show that SJAMP exhibits potent anti-HBV activity in HBV transgenic mice in a dose-dependent manner. Specifically, sixty HBV transgenic male BALB/c mice were randomly selected to receive the treatment of PBS, low dose SJAMP (30 mg kg-1), middle dose SJAMP (40 mg kg-1), high dose SJAMP (50 mg kg-1) and IFN (45 IU kg-1) for 30 d. SJAMP treatment suppressed serum HBV-DNA, and liver HBsAg and HBcAg levels in HBV-transgenic mice. The present study highlights the potential application of SJAMP in HBV therapy.

Life-span extension by a metacaspase in the yeast Saccharomyces cerevisiae.

PubMed

Hill, Sandra Malmgren; Hao, Xinxin; Liu, Beidong; Nyström, Thomas

2014-06-20

Single-cell species harbor ancestral structural homologs of caspase proteases, although the evolutionary benefit of such apoptosis-related proteins in unicellular organisms is unclear. Here, we found that the yeast metacaspase Mca1 is recruited to the insoluble protein deposit (IPOD) and juxtanuclear quality-control compartment (JUNQ) during aging and proteostatic stress. Elevating MCA1 expression counteracted accumulation of unfolded proteins and aggregates and extended life span in a heat shock protein Hsp104 disaggregase- and proteasome-dependent manner. Consistent with a role in protein quality control, genetic interaction analysis revealed that MCA1 buffers against deficiencies in the Hsp40 chaperone YDJ1 in a caspase cysteine-dependent manner. Life-span extension and aggregate management by Mca1 was only partly dependent on its conserved catalytic cysteine, which suggests that Mca1 harbors both caspase-dependent and independent functions related to life-span control. Copyright © 2014, American Association for the Advancement of Science.

Novel action and mechanism of auranofin in inhibition of vascular endothelial growth factor receptor-3-dependent lymphangiogenesis.

PubMed

Chen, Xiaodong; Zhou, Huanjiao Jenny; Huang, Qunhua; Lu, Lin; Min, Wang

2014-01-01

Auranofin is a gold compound initially developed for the treatment of rheumatoid arthritis. Recent data suggest that auranofin has promise in the treatment of other inflammatory and proliferative diseases. However, the mechanisms of action of auranofin have not been well defined. In the present study, we identify vascular endothelial growth factor receptor-3 (VEGFR3), an endothelial cell (EC) surface receptor essential for angiogiogenesis and lymphangiogenesis, as a novel target of auranofin. In both primary EC and EC cell lines, auranofin induces downregulation of VEGFR3 in a dose-dependent manner. Auranofin at high doses (≥1 µM) decreases cellular survival protein thioredoxin reductase (TrxR2), TrxR2-dependent Trx2 and transcription factor NF-κB whereas increases stress signaling p38MAPK, leading to EC apoptosis. However, auranofin at low doses (≤0.5 µM) specifically induces downregulation of VEGFR3 and VEGFR3-mediated EC proliferation and migration, two critical steps required for in vivo lymphangiogenesis. Mechanistically, we show that auranofin-induced VEGFR3 downregulation is blocked by antioxidant N-acetyl-L-cysteine (NAC) and lysosome inhibitor chloroquine, but is promoted by proteasomal inhibitor MG132. These results suggest that auranofin induces VEGFR3 degradation through a lysosome-dependent pathway. Auranofin may be a potent therapeutic agent for the treatment of lymphangiogenesis-dependent diseases such as lymphedema and cancer metastasis.

Endothelium-dependent and independent vasorelaxant effects of aqueous extract of Tridax procumbens Lin. leaf in rat aortic rings.

PubMed

Salahdeen, Hussein M; Idowu, Gbolahan O; Murtala, Babatunde A

2012-12-01

Tridax procumbens leaf extract induced aortic relaxation in a concentration-dependent manner, for both phenylephrine (PE) and KCl- induced contractions in isolated rat aortic rings. The relaxation effect of the extract on PE-induced contraction was 57% greater than that on KCl- induced contraction. The extract caused dose-dependent relaxations in precontracted isolated rat aorta with phenylephrine; the relaxation was attenuated by the removal of endothelium. However, the relaxation responses to sodium nitroprusside were not significantly abolished by the removal of endothelium. The vasorelaxatory effect of the extract was completely abolished in presence of L-NAME. The results indicate that the vasorelaxant effect of T. procumbens extract is probably mediated by both endothelium-dependent and-independent mechanisms.

Eradication of melanoma in vitro and in vivo via targeting with a Killer-Red-containing telomerase-dependent adenovirus.

PubMed

Takehara, Kiyoto; Yano, Shuya; Tazawa, Hiroshi; Kishimoto, Hiroyuki; Narii, Nobuhiro; Mizuguchi, Hiroyuki; Urata, Yasuo; Kagawa, Shunsuke; Fujiwara, Toshiyoshi; Hoffman, Robert M

2017-08-18

Melanoma is a highly recalcitrant cancer and transformative therapy is necessary for the cure of this disease. We recently developed a telomerase-dependent adenovirus containing the fluorescent protein Killer-Red. In the present report, we first determined the efficacy of Killer-Red adenovirus combined with laser irradiation on human melanoma cell lines in vitro. Cell viability of human melanoma cells was reduced in a dose-dependent and irradiation-time-dependent manner. We used an intradermal xenografted melanoma model in nude mice to determine efficacy of the Killer-Red adenovirus. Intratumoral injection of Killer-Red adenovirus, combined with laser irradiation, eradicated the melanoma indicating the potential of a new paradigm of cancer therapy.

β-elemene reverses the drug resistance of lung cancer A549/DDP cells via the mitochondrial apoptosis pathway.

PubMed

Yao, Cheng-Cai; Tu, Yuan-Rong; Jiang, Jie; Ye, Sheng-Fang; Du, Hao-Xin; Zhang, Yi

2014-05-01

β-elemene (β-ELE) is a new anticancer drug extracted from Curcuma zedoaria Roscoe and has been widely used to treat malignant tumors. Recent studies have demonstrated that β-ELE reverses the drug resistance of tumor cells. To explore the possible mechanisms of action of β-ELE, we investigated its effects on cisplatin-resistant human lung adenocarcinoma A549/DDP cells. The effects of β-ELE on the growth of A549/DDP cells in vitro were determined by MTT assay. Apoptosis was assessed by fluorescence microscopy with Hoechst 33258 staining and flow cytometry with Annexin V-FITC/PI double staining. Mitochondrial membrane potential was assessed using JC-1 fluorescence probe and laser confocal scanning microscopy, and intracellular reactive oxygen species levels were measured by 2',7'-dichlorofluorescein-diacetate staining and flow cytometry. Cytosolic glutathione content was determined using GSH kits. The expression of cytochrome c, caspase-3, procaspase-3 and the Bcl-2 family proteins was assessed by western blotting. The results demonstrated that β-ELE inhibited the proliferation of A549/DDP cells in a time- and dose-dependent manner. Furthermore, β-ELE enhanced the sensitivity of A549/DDP cells to cisplatin and reversed the drug resistance of A549/DDP cells. Consistent with a role in activating apoptosis, β-ELE decreased mitochondrial membrane potential, increased intracellular reactive oxygen species concentration and decreased the cytoplasmic glutathione levels in a time- and dose-dependent manner. The combination of β-ELE and cisplatin enhanced the protein expression of cytochrome c, caspase-3 and Bad, and reduced protein levels of Bcl-2 and procaspase-3 in the A549/DDP lung cancer cells. These results define a pathway of procaspase‑3-β-ELE function that involves decreased mitochondrial membrane potential, leading to apoptosis triggered by the release of cytochrome c into the cytoplasm and the modulation of apoptosis-related genes. The reversal of drug resistance of the A549/DDP cell line by β-ELE may be derived from its effect in inducing apoptosis.

Effect of antiretroviral therapy use and adherence on the risk of hyperlipidemia among HIV-infected patients, in the highly active antiretroviral therapy era

PubMed Central

Tsai, Fuu-Jen; Cheng, Chi-Fung; Lai, Chih-Ho; Wu, Yang-Chang; Ho, Mao-Wang; Wang, Jen-Hsien; Tien, Ni; Liu, Xiang; Tsang, Hsinyi; Lin, Ting-Hsu; Liao, Chiu-Chu; Huang, Shao-Mei; Li, Ju-Pi; Lin, Jung-Chun; Lin, Chih-Chien; Chen, Jin-Hua; Liang, Wen-Miin; Lin, Ying-Ju

2017-01-01

HIV-infected patients exposed to antiretroviral therapy (ART) have an increased risk for hyperlipidemia and cardiovascular disease. We performed a longitudinal, comprehensive, and population-based study to investigate the cumulative effect of different types of ART regimens on hyperlipidemia risk in the Taiwanese HIV/ART cohort. A total of 13,370 HIV-infected patients (2,674 hyperlipidemia and 10,696 non-hyperlipidemia patients) were recruited after matching for age, gender, and the first diagnosis date of HIV infection by using the National Health Insurance Research Database in Taiwan. Hyperlipidemia risk associated with cumulative ART use, ART adherence, and their combination was assessed. The matched hyperlipidemia group had a larger number of patients using ART and a higher incidence of comorbidities, specifically, respiratory disease and diabetes. Patients with high ART dosage and dose-dependent manner adherence, respectively, demonstrated an increased risk of hyperlipidemia. For single ART regimens, patients receiving nucleoside reverse-transcriptase inhibitors (NRTI/NRTI)- containing regimen had the highest hyperlipidemia risk, followed by protease inhibitor (PI)- containing and non-NRTI- containing regimens. For combination ART regimens, patients receiving a NRTI/NRTI + PI regimen had the highest hyperlipidemia risk. An increased cumulative drug dose was observed in patients who received the PI, NRTI/NRTI, NRTI, and NNRTI regimens in the hyperlipidemia group, when compared to the non-hyperlipidemia group. In conclusion, ART cumulative use, adherence, and regimen may affect hyperlipidemia risk among HIV-infected patients in a dose-dependent manner. PMID:29290955

Lactobacillus salivarius REN inhibits rat oral cancer induced by 4-nitroquioline 1-oxide.

PubMed

Zhang, Ming; Wang, Fang; Jiang, Lu; Liu, Ruihai; Zhang, Lian; Lei, Xingen; Li, Jiyou; Jiang, Jingli; Guo, Huiyuan; Fang, Bing; Zhao, Liang; Ren, Fazheng

2013-07-01

Despite significant advances in cancer therapy, cancer-related mobility and mortality are still rising. Alternative strategies such as cancer prevention thus become essential. Probiotics represent an emerging option for cancer prevention, but studies are limited to colon cancers. The efficiency of probiotics in the prevention of other cancers and the correlative mechanism remains to be explored. A novel probiotics Lactobacillus salivarius REN (L. salivarius REN) was isolated from centenarians at Bama of China, which showed highly potent antigenotoxicity in an initial assay. 4-nitroquioline 1-oxide (4NQO)-induced oral cancer model was introduced to study the anticancer activity of L. salivarius REN in vivo. The results indicated that oral administration of probiotic L. salivarius REN or its secretions could effectively suppress 4NQO-induced oral carcinogenesis in the initial and postinitial stage, and the inhibition was in a dose-dependent manner. A significant decrease of neoplasm incidence (65%-0%) was detected in rats fed with the high dose of L. salivarius REN [5 × 10(10) CFU/kg body weight (bw)/d]. In vivo evidences indicated that the probiotics inhibited 4NQO-induced oral cancer by protecting DNA against oxidative damage and downregulating COX-2 expression. L. salivarius REN treatment significantly decreased the expression of proliferating cell nuclear antigen (PCNA) and induced apoptosis in a dose-dependent manner. Our findings suggest that probiotics may act as potential agents for oral cancer prevention. This is the first report showing the inhibitory effect of the probiotics on oral carcinogenesis. ©2013 AACR.

Effects of glucose, insulin and triiodothyroxine on leptin and leptin receptor expression and the effects of leptin on activities of enzymes related to glucose metabolism in grass carp (Ctenopharyngodon idella) hepatocytes.

PubMed

Lu, Rong-Hua; Zhou, Yi; Yuan, Xiao-Chen; Liang, Xu-Fang; Fang, Liu; Bai, Xiao-Li; Wang, Min; Zhao, Yu-Hua

2015-08-01

Leptin is an important regulator of appetite and energy expenditure in mammals, but its role in fish metabolism control is poorly understood. Our previous studies demonstrated that leptin has an effect on the regulation of food intake and energy expenditure as well as lipid metabolism (stimulation of lipolysis and inhibition of adipogenesis) in the grass carp Ctenopharyngodon idella. To further investigate the role of leptin in fish, the effects of glucose, insulin and triiodothyroxine (T3) on the expression levels of leptin and leptin receptor (Lepr) and the effects of leptin on the activities of critical glucose metabolism enzymes in grass carp hepatocytes were evaluated in the present study. Our data indicated that leptin gene expression was induced by glucose in a dose-dependent manner, while Lepr gene expression exhibited a biphasic change. A high dose of insulin (100 ng/mL) significantly up-regulated the expression of leptin and Lepr. Leptin expression was markedly up-regulated by a low concentration of T3 but inhibited by a high concentration of T3. T3 up-regulated Lepr expression in a dose-dependent manner. Together, these data suggest that leptin had a close relationship with three factors (glucose, insulin and T3) and might participate in the regulation of glucose metabolism in grass carp. In addition, we also found that leptin affected the activities of key enzymes that are involved in glucose metabolism, which might be mediated by insulin receptor substrate-phosphoinositol 3-kinase signaling.

Ultrastructural and DNA damaging effects of lead nitrate in the liver.

PubMed

Narayana, K; Al-Bader, Maie

2011-01-01

A ubiquitous environmental toxicant - lead is known to affect several organ systems. This study was designed to investigate the effects of lead nitrate exposure on liver structure and DNA fragmentation. Adult male Wistar rats were treated orally with lead nitrate at the dose levels of 0%, 0.5% and 1% for 60 days and sacrificed on the next day. The liver was processed for thick sections and evaluated after toludine blue staining and by electron microscopy after staining with uranyl acetate and lead citrate. The DNA damage was assessed by DNA fragmentation assay. The liver weight was not significantly affected in the experimental groups. Hepatocyte nuclei were not shrunk, instead lead was mitogenic to hepatocytes as indicated by an increase in the number of binucleated hepatocytes (P<0.05). The number of mitochondria per hepatocyte decreased in a dose-dependent manner (P<0.05). Qualitatively, the necrotic changes such as small to large-sized cytoplasmic vacuoles often displacing the organelles, decrease in hepatocyte microvilli, degeneration of mitochondria, and vacuolar encroachment of nuclei and dilatation of sinusoids were observed. The qualitative changes were induced in a dose-dependent manner. Kupffer cells or Ito cells did not present any notable structural changes. Although the electrophoretic flow of DNA fragments was observed in lead-treated groups, these changes were not significantly different from that in control as evaluated by optical density. In conclusion, lead induces necrotic changes with simultaneous mitogenic activity; however, it does not induce significant DNA damage in the liver. Copyright © 2009 Elsevier GmbH. All rights reserved.

A Comparison of the Effects of Benzalkonium Chloride on Ocular Surfaces between C57BL/6 and BALB/c Mice

PubMed Central

Yang, Qian; Zhang, Yafang; Liu, Xiuping; Wang, Nan; Song, Zhenyu; Wu, Kaili

2017-01-01

Models of benzalkonium chloride (BAC)-induced ocular disruption have been created and are widely used in various animals. This study aimed to compare the effects of BAC on the ocular surfaces of C57BL/6 and BALB/c mice. C57BL/6 and BALB/c mice were treated separately with BAC eye-drops at different concentrations. Eyes were evaluated by scoring epithelial disruption, corneal opacity and neovascularization in vivo, and by histological assays with hematoxylin/eosin (H/E) and periodic acid-Schiff stainings and by determining the expression of inflammatory factors in vitro on Days 7 and 14. The in vivo corneal epithelial disruption, corneal edema/opacity and neovascularization, which were in accordance with the results of the H/E staining and peaked at Day 7, were observed in a dose-dependent manner in the BAC-treated mice, with more severe signs in the C57BL/6 mice than the BALB/c mice. The loss of conjunctival goblet cells in the conjunctivas and the increasing expression of monocyte chemoattractant protein 1 (MCP-1), growth-regulated protein alpha (GROa) and macrophage inflammatory protein-1 alpha (MIP-1a) in the corneas were found in a dose-dependent manner in both strains of mice. Topical application of BAC can dramatically disrupt the ocular surfaces of C57BL/6 and BALB/c mice, and the disruptions were much more severe in the C57BL/6 mice that received high doses of BAC. PMID:28245636

Ortho-aminoazotoluene activates mouse constitutive androstane receptor (mCAR) and increases expression of mCAR target genes

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

Smetanina, Mariya A., E-mail: maria.smetanina@gmail.com; Laboratory of Gene Expression Control, Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 10, Novosibirsk 630090; Group of Pharmacogenomics, Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, prospekt Lavrentyeva 8, Novosibirsk 630090

2'-3-dimethyl-4-aminoazobenzene (ortho-aminoazotoluene, OAT) is an azo dye and a rodent carcinogen that has been evaluated by the International Agency for Research on Cancer (IARC) as a possible (class 2B) human carcinogen. Its mechanism of action remains unclear. We examined the role of the xenobiotic receptor Constitutive Androstane Receptor (CAR, NR1I3) as a mediator of the effects of OAT. We found that OAT increases mouse CAR (mCAR) transactivation in a dose-dependent manner. This effect is specific because another closely related azo dye, 3'-methyl-4-dimethyl-aminoazobenzene (3'MeDAB), did not activate mCAR. Real-time Q-PCR analysis in wild-type C57BL/6 mice revealed that OAT induces the hepaticmore » mRNA expression of the following CAR target genes: Cyp2b10, Cyp2c29, Cyp3a11, Ugt1a1, Mrp4, Mrp2 and c-Myc. CAR-null (Car{sup -/-}) mice showed no increased expression of these genes following OAT treatment, demonstrating that CAR is required for their OAT dependent induction. The OAT-induced CAR-dependent increase of Cyp2b10 and c-Myc expression was confirmed by Western blotting. Immunohistochemistry analysis of wild-type and Car{sup -/-} livers showed that OAT did not acutely induce hepatocyte proliferation, but at much later time points showed an unexpected CAR-dependent proliferative response. These studies demonstrate that mCAR is an OAT xenosensor, and indicate that at least some of the biological effects of this compound are mediated by this nuclear receptor. - Highlights: > The azo dye and mouse carcinogen OAT is a very effective mCAR activator. > OAT increases mCAR transactivation in a dose-dependent manner. > OAT CAR-dependently increases the expression of a specific subset of CAR target genes. > OAT induces an unexpectedly deferred, but CAR-dependent hepatocyte proliferation.« less

Platelet-derived growth factor regulates K-Cl cotransport in vascular smooth muscle cells.

PubMed

Zhang, Jing; Lauf, Peter K; Adragna, Norma C

2003-03-01

Platelet-derived growth factor (PDGF), a potent serum mitogen for vascular smooth muscle cells (VSMCs), plays an important role in membrane transport regulation and in atherosclerosis. K-Cl cotransport (K-Cl COT/KCC), the coupled-movement of K and Cl, is involved in ion homeostasis. VSMCs possess K-Cl COT activity and the KCC1 and KCC3 isoforms. Here, we report on the effect of PDGF on K-Cl COT activity and mRNA expression in primary cultures of rat VSMCs. K-Cl COT was determined as the Cl-dependent Rb influx and mRNA expression by semiquantitative RT-PCR. Twenty four-hour serum deprivation inhibited basal K-Cl COT activity. Addition of PDGF increased total protein content and K-Cl COT activity in a time-dependent manner. PDGF activated K-Cl COT in a dose-dependent manner, both acutely (10 min) and chronically (12 h). AG-1296, a selective inhibitor of the PDGF receptor tyrosine kinase, abolished these effects. Actinomycin D and cycloheximide had no effect on the acute PDGF activation of K-Cl COT, suggesting posttranslational regulation by the drug. Furthermore, PDGF increased KCC1 and decreased KCC3 mRNA expression in a time-dependent manner. These results indicate that chronic activation of K-Cl COT activity by PDGF may involve regulation of the two KCC mRNA isoforms, with KCC1 playing a dominant role in the mechanism of PDGF-mediated activation.

Synthetic detergents induced-biochemical and histological changes in skin of guinea pigs.

PubMed

Agarwal, C; Mathur, A K; Gupta, B N; Singh, A; Shanker, R

1990-06-01

The linear alkylbenzene sulphonate (LAS) based synthetic detergents-induced decrease in lipid peroxydation and increase in histamine content in exposed skin of guinea pigs in a dose-dependent manner. Histopathological alterations of exposed skin included moderate degree of hyperkeratinization at lower concentration but necrosis, scarring, sloughing as well as discontinuity of epidermis at higher concentrations. The results shows that the contact of skin with detergents causes dermal toxicity.

Human serum provided additional values in growth factors supplemented medium for human chondrocytes monolayer expansion and engineered cartilage construction.

PubMed

Chua, K H; Aminuddin, B S; Fuzina, N H; Ruszymah, B H I

2004-05-01

We have previously formulated an optimized human chondrocytes growth medium based on 2% fetal bovine serum supplementation. For clinical usage, the animal serum must be replaced by patient own serum. We investigated the effects of human serum concentration for human nasal septum chondrocytes monolayer culture and cartilage reconstruction. Human serum demonstrated a dose dependent manner in promoting chondrocytes growth and cartilage engineering.

Secondary metabolites from Marchantia paleacea calluses and their allelopathic effects on Arabidopsis seed growth.

PubMed

Wang, Lei; Wang, Li-Ning; Zhao, Yu; Lou, Hong-Xiang; Cheng, Ai-Xia

2013-01-01

Rapid-growth Marchantia paleacea calluses were induced on MSK2 medium through surface sterilisation of the capsula. Ten known compounds including two steroids (1-2), six bibenzyls (3, 5-9), a flavonoid (10), and a terpenoid (4) were isolated from these calluses. The allelopathic effect of the six bibenzyls was assessed in Arabidopsis thaliana. Results revealed that bibenzyls could inhibit seedling growth in a dose-dependent manner.

Differential regulation of smooth muscle contraction in rabbit internal anal sphincter by substance P and bombesin.

PubMed

Bitar, K N; Hillemeier, C; Biancani, P

1990-01-01

Substance P and bombesin induce contraction of isolated IAS smooth muscle cells by different intracellular mechanisms. The cells contracted in a dose dependent manner to both peptides. The kinetics of contraction were different. Substance P induced contraction peaked at 30 seconds and declined in a time dependent manner while bombesin induced contraction peaked at 30 seconds and was maintained for up to 8 minutes. The absence of extracellular calcium in the medium (0 calcium and 2 mM EGTA) had no affect on substance P induced contraction while it blocked bombesin induced contraction. Substance P induced contraction was blocked by the calmodulin antagonist W7 (10(-9)M) and was not affected by the PKC antagonist H7 (10(-6)M). Bombesin induced contraction was blocked by the PKC antagonist H7 and was not affected by the calmodulin antagonist W7. Our data indicate that substance P induces a transient contraction utilizing intracellular calcium and a calmodulin dependent pathway, while bombesin induces a sustained contraction utilizing calcium from extracellular sources and a calmodulin independent pathway.

Prevotella intermedia induces prostaglandin E2 via multiple signaling pathways.

PubMed

Guan, S-M; Fu, S-M; He, J-J; Zhang, M

2011-01-01

Prostaglandin E(2) (PGE(2)) plays important roles in the bone resorption of inflammatory diseases such as rheumatoid arthritis and periodontitis via specific prostaglandin receptors (i.e., EP1-EP4). In this study, the authors examined whether Prevotella intermedia regulates PGE(2) production and EP expression in human periodontal ligament fibroblasts (hPDLs); they also explored the potential signaling pathways involved in PGE(2) production. P. intermedia induced PGE(2) production and cyclooxygenase-2 (COX-2) expression in a dose- and time-dependent manner. Indomethacin and NS-398 completely abrogated the P. intermedia-induced PGE(2) production without modulating COX-2 expression. Specific inhibitors of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, phosphatidylinositol 3-kinase, and protein kinase C--but not c-AMP and protein kinase A--significantly attenuated the P. intermedia-induced COX-2 and PGE(2) expression. P. intermedia reduced EP1 expression in a concentration- and time-dependent manner. The results indicate that the COX-2-dependent induction of PGE(2) by P. intermedia in hPDLs is mediated by multiple signaling pathways.

[Valsartan inhibits angiotensin II-Notch signaling of mesangial cells induced by high glucose].

PubMed

Yuan, Qin; Lyu, Chuan; Wu, Can; Lei, Sha; Shao, Ying; Wang, Qiuyue

2016-01-01

To explore the role of angiotensin II (Ang II)-Notch signaling in high glucose-induced secretion of extracellular matrix of rat mesangial cells (RMCs) and to further investigate the protective effect of valsartan (one of Ang II receptor blockers) on kidney. Subcultured RMCs were divided into groups as follows: normal glucose group (5.5 mmol/L glucose); high glucose group (30 mmol/L glucose); high concentration of mannitol as osmotic control group (5.5 mmol/L glucose and 24.5 mmol/L mannitol); normal glucose plus 1 μmol/L N-[N-(3, 5-difluorophenacetyl)-L-alanyl ]-S-phenylglycine t-butyl ester (DAPT) group; normal glucose plus (1, 5, 10) μmol/L valsartan group; high glucose plus 1 μmol/L DAPT group; high glucose plus (1, 5, 10) μmol/L valsartan group. Cells and supernatants were harvested after 12, 24 and 48 hours. Notch1 expression was examined by Western blotting. Secretion of transforming growth factor (TGF-β) and fibronectin (FN) were detected by ELISA. Compared to the normal glucose group, Notch1 expression was elevated in the high glucose group after 12 hours, and peaked at 24 hours. Besides, secretion of TGF-β and FN were much higher in the high glucose group than in the normal glucose group in a time-dependent manner. Compared to the untreated group, Notch1 expression decreased in a dose-dependent manner in the valsartan or DAPT treated group under high glucose after 24 hours. After pre-treatment by either valsartan or DAPT in the high glucose group, secretion of TGF-β and FN obviously decreased as compared to the untreated group. Hyperglycemia could stimulate activation of Notch signaling in cultured RMCs, which may increase secretion of downstream fibrotic factors such as TGF-β and FN. Valsartan may decrease the secretion of downstream FN in a dose-dependent manner via inhibiting AngII-Notch signaling.

Curcumin induces autophagic cell death in Spodoptera frugiperda cells.

PubMed

Veeran, Sethuraman; Shu, Benshui; Cui, Gaofeng; Fu, Shengjiao; Zhong, Guohua

2017-06-01

The increasing interest in the role of autophagy (type II cell death) in the regulation of insect toxicology has propelled study of investigating autophagic cell death pathways. Turmeric, the rhizome of the herb Curcuma longa (Mañjaḷ in Tamil, India and Jiānghuáng in Chinese) have been traditionally used for the pest control either alone or combination with other botanical pesticides. However, the mechanisms by which Curcuma longa or curcumin exerts cytotoxicity in pests are not well understood. In this study, we investigated the potency of Curcuma longa (curcumin) as a natural pesticide employing Sf9 insect line. Autophagy induction effect of curcumin on Spodoptera frugiperda (Sf9) cells was investigated using various techniques including cell proliferation assay, morphology analysis with inverted phase contrast microscope and Transmission Electron Microscope (TEM) analysis. Autophagy was evaluated using the fluorescent dye monodansylcadaverine (MDC). Cell death measurement was examined using 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) within the concentrations of 5-15μg/mL. Curcumin inhibited the growth of the Sf9 cells and induced autophagic cell death in a time and dose dependent manner. Staining the cells with MDC showed the presence of autophagic vacuoles while increased in a dose and time dependent manner. At the ultrastructural level transmission electron microscopy, cells revealed massive autophagy vacuole accumulation and absence of chromatin condensation. Protein expression levels of ATG8-I and ATG8-II, well-established markers of autophagy related protein were elevated in a time dependent manner after curcumin treatment. The present study proves that curcumin induces autophagic cell death in Sf9 insect cell line and this is the first report of cytotoxic effect of curcumin in insect cells and that will be utilized as natural pesticides in future. Copyright © 2017. Published by Elsevier Inc.

Single- and Repeat-dose Oral Toxicity Studies of Lithospermum erythrorhizon Extract in Dogs

PubMed Central

Hwang, Jae-Sik; Kim, Myoung-Jun; Choi, Young Whan; Han, Kyoung-Goo; Kang, Jong-Koo

2015-01-01

Lithospermum erythrorhizon has long been used in traditional Asian medicine for the treatment of diseases, including skin cancer. The oral toxicity of a hexane extract of Lithospermum erythrorhizon root (LEH) was investigated in Beagle dogs by using single escalating doses, two-week dose range-finding, and 4-week oral repeat dosing. In the single dose-escalating oral toxicity study, no animal died, showed adverse clinical signs, or changes in body weight gain at LEH doses of up to 2,000 mg/kg. In a 2 week dose range-finding study, no treatment-related adverse effects were detected by urinalysis, hematology, blood biochemistry, organ weights, or gross and histopathological examinations at doses of up to 500 mg LEH/kg/day. In the 4 week repeat-dose toxicity study, a weight loss or decreased weight gain was observed at 300 mg/kg/day. Although levels of serum triglyceride and total bilirubin were increased in a dose dependent manner, there were no related morphological changes. Based on these findings, the sub-acute no observable adverse effect level for 4-week oral administration of LEH in Beagles was 100 mg/kg/day. PMID:25874036

Single- and Repeat-dose Oral Toxicity Studies of Lithospermum erythrorhizon Extract in Dogs.

PubMed

Nam, Chunja; Hwang, Jae-Sik; Kim, Myoung-Jun; Choi, Young Whan; Han, Kyoung-Goo; Kang, Jong-Koo

2015-03-01

Lithospermum erythrorhizon has long been used in traditional Asian medicine for the treatment of diseases, including skin cancer. The oral toxicity of a hexane extract of Lithospermum erythrorhizon root (LEH) was investigated in Beagle dogs by using single escalating doses, two-week dose range-finding, and 4-week oral repeat dosing. In the single dose-escalating oral toxicity study, no animal died, showed adverse clinical signs, or changes in body weight gain at LEH doses of up to 2,000 mg/kg. In a 2 week dose range-finding study, no treatment-related adverse effects were detected by urinalysis, hematology, blood biochemistry, organ weights, or gross and histopathological examinations at doses of up to 500 mg LEH/kg/day. In the 4 week repeat-dose toxicity study, a weight loss or decreased weight gain was observed at 300 mg/kg/day. Although levels of serum triglyceride and total bilirubin were increased in a dose dependent manner, there were no related morphological changes. Based on these findings, the sub-acute no observable adverse effect level for 4-week oral administration of LEH in Beagles was 100 mg/kg/day.

Methylene Blue Facilitates Memory Retention in Zebrafish in a Dose-Dependent Manner.

PubMed

Echevarria, David J; Caramillo, Erika M; Gonzalez-Lima, Francisco

2016-12-01

Methylene blue (MB) is an FDA-grandfathered drug with memory-enhancing effects at low doses, but opposite effects at high doses. We investigated the effects of four MB doses (0.1, 0.5, 5.0, or 10.0 μM) on zebrafish memory retention in the T-maze task. After training fish to swim into a certain arm of the T-maze, the fish were placed into a tank containing one of the four MB doses or a control tank containing blue food dye. Subsequently, fish were placed into the T-maze for memory retention testing. Results indicated that MB produced hormetic dose-response effects on memory. Fish that received the 0.5 μM dose performed significantly better at the T-maze than those that received higher doses. Fish who received 5.0 μM did not exhibit a significant difference in performance from control fish, and the fish that received the 10.0 μM dose performed significantly worse than lower doses. These findings support the utility of zebrafish in comparative research and their potential value for testing of MB and other neuropsychopharmacological treatments in animal models of memory disorders.

Mechanisms of carcinogensis: dose response

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

Gehring, P.J.; Blau, G.E.

There is great controversy whether the carcinogenicity of chemicals is dose-dependent and whether a threshold dose exists below which cancer will not be induced by exposure. Evidence for dose-dependency exists and is believed to be accepted generally if extricated as it should be from the threshold concept. The threshold concept conflict is not likely to be resolved in the foreseeable future; proponents and opponents argue their case in a manner similar to those arguing religion. In this paper the various arguments are reviewed. Subsequently, a chemical process model for carcinogenesis is developed based on the generally accepted evidence that themore » carcinogenic activity of many chemicals can be related to electrophilic alkylation of DNA. Using this model, some incidence of cancer, albeit negligible, will be predicted regardless how low the dose. However, the model revelas that the incidence of cancer induced by real-life exposures is likely to be greatly overestimated by currently used stochastic statistical extrapolations. Even more important, modeling of the chemical processes involved in the fate of a carcinogenic chemical in the body reveals experimental approaches to elucidating the mechanism(s) of carcinogenesis and ultimately a more scientifically sound basis for assessing the hazard of low-level exposure to a chemical carcinogen.« less

Evaluation of the Anxiolytic Activity of NR-ANX-C (a Polyherbal Formulation) in Ethanol Withdrawal-Induced Anxiety Behavior in Rats.

PubMed

Mohan, L; Rao, U S C; Gopalakrishna, H N; Nair, V

2011-01-01

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety.

Evaluation of the Anxiolytic Activity of NR-ANX-C (a Polyherbal Formulation) in Ethanol Withdrawal-Induced Anxiety Behavior in Rats

PubMed Central

Mohan, L.; Rao, U. S. C.; Gopalakrishna, H. N.; Nair, V.

2011-01-01

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety. PMID:20953426

Effect of dietary α-lipoic acid on the mRNA expression of genes involved in drug metabolism and antioxidation system in rat liver.

PubMed

Ide, Takashi

2014-08-14

In the present study, the mRNA levels of hepatic proteins involved in the drug metabolism of rats fed α-lipoic acid were evaluated by DNA microarray and real-time PCR analyses. Experimental diets containing 0, 0·1, 0·25 and 0·5 % (w/w) α-lipoic acid were fed to four groups of rats consisting of seven animals each for 21 d. DNA microarray analysis revealed that the diet containing 0·5 % α-lipoic acid significantly (P< 0·05) increased the mRNA levels of various phase I drug-metabolising enzymes up to 15-fold and phase II enzymes up to 52-fold in an isoenzyme-specific manner. α-Lipoic acid also up-regulated the mRNA levels of some members of the ATP-binding cassette transporter superfamily, presumed to be involved in the exportation of xenobiotics, up to 6·6-fold. In addition, we observed that α-lipoic acid increased the mRNA levels of many proteins involved in antioxidation, such as members of the thiol redox system (up to 5·5-fold), metallothioneins (up to 12-fold) and haeme oxygenase 1 (1·5-fold). These results were confirmed using real-time PCR analysis, and α-lipoic acid dose dependently increased the mRNA levels of various proteins involved in drug metabolism and antioxidation. Consistent with these observations, α-lipoic acid dose dependently increased the hepatic concentration of glutathione and the activities of glutathione reductase and glutathione transferase measured using 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene as substrates, but decreased the hepatic and serum concentrations of malondialdehyde. In conclusion, the present study unequivocally demonstrated that α-lipoic acid increases the mRNA expression of proteins involved in drug metabolism and antioxidation in the liver.

Intracellular Networks of the PI3K/AKT and MAPK Pathways for Regulating Toxoplasma gondii-Induced IL-23 and IL-12 Production in Human THP-1 Cells

PubMed Central

Choi, In-Wook; Ismail, Hassan Ahmed Hassan Ahmed; Zhou, Wei; Cha, Guang-Ho; Zhou, Yu; Yuk, Jae-Min; Jo, Eun-Kyeong; Lee, Young-Ha

2015-01-01

Interleukin (IL)-23 and IL-12 are closely related in structure, and these cytokines regulate both innate and adaptive immunity. However, the precise signaling networks that regulate the production of each in Toxoplasma gondii-infected THP-1 monocytic cells, particularly the PI3K/AKT and MAPK signaling pathways, remain unknown. In the present study, T. gondii infection upregulated the expression of IL-23 and IL-12 in THP-1 cells, and both cytokines increased with parasite dose. IL-23 secretion was strongly inhibited by TLR2 monoclonal antibody (mAb) treatment in a dose-dependent manner and by TLR2 siRNA transfection, whereas IL-12 secretion was strongly inhibited by TLR4 mAb treatment dose-dependently and by TLR4 siRNA transfection. IL-23 production was dose-dependently inhibited by the PI3K inhibitors LY294002 and wortmannin, whereas IL-12 production increased dose-dependently. THP-1 cells exposed to live T. gondii tachyzoites underwent rapid p38 MAPK, ERK1/2 and JNK activation. IL-23 production was significantly upregulated by the p38 MAPK inhibitor SB203580 dose-dependently, whereas pretreatment with 10 μM SB203580 significantly downregulated IL-12 production. ERK1/2 inhibition by PD98059 was significantly downregulated IL-23 production but upregulated IL-12 production. JNK inhibition by SP600125 upregulated IL-23 production, but IL-12 production was significantly downregulated dose-dependently. T. gondii infection resulted in AKT activation, and AKT phosphorylation was inhibited dose-dependently after pretreatment with PI3K inhibitors. In T. gondii-infected THP-1 cells, ERK1/2 activation was regulated by PI3K; however, the phosphorylation of p38 MAPK and JNK was negatively modulated by the PI3K signaling pathway. Collectively, these results indicate that IL-23 production in T. gondii-infected THP-1 cells was regulated mainly by TLR2 and then by PI3K and ERK1/2; however, IL-12 production was mainly regulated by TLR4 and then by p38 MAPK and JNK. Our findings provide new insight concerning the intracellular networks of the PI3K/AKT and MAPK signaling cascades for regulating T. gondii-induced IL-23 and IL-12 secretion in human monocytic cells. PMID:26528819

Oral administration of leaf extracts of Momordica charantia affect reproductive hormones of adult female Wistar rats

PubMed Central

Adewale, Osonuga Odusoga; Oduyemi, Osonuga Ifabunmi; Ayokunle, Osonuga

2014-01-01

Objective To determine the effect of graded doses of aqueous leaf extracts of Momordica charantia on fertility hormones of female albino rats. Methods Twenty adult, healthy, female Wistar rats were divided into four groups: low dose (LD), moderate dose (MD) and high dose (HD) groups which received 12.5 g, 25.0 g, 50.0 g of the leaf extract respectively and control group that was given with water ad libatum. Result Estrogen levels reduced by 6.40 nmol/L, 10.80 nmol/L and 28.00 nmol/L in the LD, MD and HD groups respectively while plasma progesterone of rats in the LD, MD and HD groups reduced by 24.20 nmol/L, 40.8 nmol/L and 59.20 nmol/L respectively. Conclusion Our study has shown that the antifertility effect of Momordica charantia is achieved in a dose dependent manner. Hence, cautious use of such medication should be advocated especially when managing couples for infertility. PMID:25183143

Sodium Iodate Selectively Injuries the Posterior Pole of the Retina in a Dose-Dependent Manner: Morphological and Electrophysiological Study

PubMed Central

Machalińska, Anna; Lubiński, Wojciech; Kłos, Patrycja; Kawa, Miłosz; Baumert, Bartłomiej; Penkala, Krzysztof; Grzegrzółka, Ryszard; Karczewicz, Danuta; Wiszniewska, Barbara

2010-01-01

Sequential morphological and functional features of retinal damage in mice exposed to different doses (40 vs. 20 mg/kg) of sodium iodate (NaIO3) were analyzed. Retinal morphology, apoptosis (TUNEL assay), and function (electroretinography; ERG) were examined at several time points after NaIO3 administration. The higher dose of NaIO3 caused progressive degeneration of the whole retinal area and total suppression of scotopic and photopic ERG. In contrast, the lower dose induced much less severe degeneration in peripheral part of retina along with a moderate decline of b- and a-wave amplitudes in ERG, corroborating the presence of regions within retina that retain their function. The peak of photoreceptor apoptosis was found on the 3rd day, but the lower dose induced more intense reaction within the central retina than in its peripheral region. In conclusion, these results indicate that peripheral area of the retina reveals better resistance to NaIO3 injury than its central part. PMID:20725778

Angiotensin I- and II- and norepinephrine-mediated pressor responses in an ancient holostean fish, the bowfin (Amia calva).

PubMed

Butler, D G; Oudit, G Y; Cadinouche, M Z

1995-06-01

Dorsal aortic blood pressure (PSYS, systolic; PDIAS, diastolic; and PDA, mean) and heart rate (HR) were measured in resting freshwater bowfins (n = 6), Amia calva L., before and after i.v. injections of 50, 100, 200, 500, and 1000 ng.kg-1 of synthetic [Asn1, Val5]-angiotensin II (ANG II). Baseline PSYS, PDIAS, and PDA were 27.7 +/- 2.8, 22.4 +/- 1.8, and 24.5 +/- 2 mm Hg, respectively. Bowfins were only moderately responsive to ANG II in a stepwise manner and the increase in blood pressure became significant only at the two highest doses; lower doses tended only to increase arterial pressure. Pressor responses due to 200 and 500 ng.kg-1 decayed over a greater time period compared with other doses. alpha-Adrenergic blockade abolished 70% of the ANG II-mediated pressor responses. Eel, salmon, and goosefish angiotensin I (ANG I; 500 ng.kg-1) elicited similar vasopressor responses (magnitude and time course) which were eliminated by prior angiotensin converting enzyme inhibition (captopril; 2-10 mg.kg-1). Bullfrog ANG I evoked a pressor effect, only at a higher dose (5000 ng.kg-1). Consecutive norepinephrine (NE) injections (100, 200, 500, and 1000 ng.kg-1) increased PSYS, PDIAS, and PDA in a dose-dependent manner which was dependent on alpha-adrenoceptors since phentolamine (1-3 mg.kg-1) abolished 80% of the pressor action of NE. PSYS was elevated by 100 ng.kg-1 of NE but PDIAS and PDA were significantly increased only at 200 ng.kg-1 ANG II and NE had no measurable chronotropic effect and resting HR (27.2 +/- 0.8 beats.min-1) was unchanged. Captopril and phentolamine treatments produced rapid hypotension and bradycardia (25-30%) which lasted from 15 to 30 and 20 to 40 min, respectively. The rising and decreasing phases of the NE-mediated pressor responses had shorter durations than ANG II effects. Tachyphylaxis occurred with the high doses of ANG II and NE. The data show that in the ancient bowfin, which evidently lacks renal juxtaglomerular cells, the cardiovascular system can be regulated by the renin-angiotensin system and NE.

Intervention effect and dose-dependent response of tanreqing injection on airway inflammation in lipopolysaccharide-induced rats.

PubMed

Dong, Shoujin; Zhong, Yunqing; Yang, Kun; Xiong, Xiaoling; Mao, Bing

2013-08-01

To assess the effect of Tanreqing injection on airway inflammation in rats. A rat model of airway inflammation was generated with lipopolysaccharide (LPS). Tanreqing injection was given by intratracheal instillation, and bronchoalveolar lavage fluid (BALF) from the right lung was collected. BALF total cell and neutrophil counts were then determined. In addition, BALF levels of inflammatory cytokines interleukin-13, cytokine-induced neutrophil chemoat-tractant-1, and tumor necrosis factor-alpha were measured using enzyme linked immunosorbent assay. The middle lobe of the right lung was stained with hematoxylin-eosin and histological changes examined. LPS increased airway inflammation, decreased BALF inflammatory cell count, inflammatory cytokine levels, and suppressed leukocyte influx of the lung. The LPS-induced airway inflammation peaked at 24 h, decreased beginning at 48 h, and had decreased markedly by 96 h. Tanreqing injection contains anti-inflammatory properties, and inhibits airway inflammation in a dose-dependent manner.

Ethanol inhibits human bone cell proliferation and function in vitro

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

Friday, K.E.; Howard, G.A.

1991-06-01

The direct effects of ethanol on human bone cell proliferation and function were studied in vitro. Normal human osteoblasts from trabecular bone chips were prepared by collagenase digestion. Exposure of these osteoblasts to ethanol in concentrations of 0.05% to 1% for 22 hours induced a dose-dependent reduction in bone cell DNA synthesis as assessed by incorporation of 3H-thymidine. After 72 hours of ethanol exposure in concentrations of 0.01% to 1%, protein synthesis as measured by 3H-proline incorporation into trichbroacetic acid (TCA)-precipitable material was reduced in a dose-dependent manner. Human bone cell protein concentrations and alkaline phosphatase total activity were significantlymore » reduced after exposure to 1% ethanol for 72 hours, but not with lower concentrations of ethanol. This reduction in osteoblast proliferation and activity may partially explain the development of osteopenia in humans consuming excessive amounts of ethanol.« less

Discovery and evaluation of novel anti-inflammatory derivatives of natural bioactive curcumin

PubMed Central

Zhang, Yali; Jiang, Xin; Peng, Kesong; Chen, Chengwei; Fu, Lili; Wang, Zhe; Feng, Jianpeng; Liu, Zhiguo; Zhang, Huajie; Liang, Guang; Pan, Zheer

2014-01-01

Curcumin is a natural active product that has various pharmacological activities such as anti-inflammatory effects. Here, we report the synthesis and evaluation of 34 monocarbonyl curcumin analogs as novel anti-inflammatory agents. Among the analogs, the symmetrical heterocyclic type displayed the strongest inhibition of lipopolysaccharide (LPS)-stimulated expression of pro-inflammatory cytokines in macrophages. Analogs S1–S5 and AS29 reduced tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production in a dose-dependent manner and also displayed excellent stability and low cytotoxicity in vitro. In addition, analog S1 dose-dependently inhibited LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation. Furthermore, analogs S1 and S4 displayed a significant protective effect on LPS-induced septic death in mouse models, with 40% and 50% survival rates, respectively. These data demonstrate that the heterocyclic monocarbonyl curcumin analogs have potential therapeutic effects in acute inflammatory diseases. PMID:25395833

Flavonoids from Theobroma cacao down-regulate inflammatory mediators.

PubMed

Ramiro, Emma; Franch, Angels; Castellote, Cristina; Pérez-Cano, Francisco; Permanyer, Joan; Izquierdo-Pulido, Maria; Castell, Margarida

2005-11-02

In the present study, we report the effects of a cocoa extract on the secretion and RNA expression of various proinflammatory mediators by macrophages. Monocyte chemoattractant protein 1 and tumor necrosis factor alpha (TNFalpha) were significantly and dose-dependently diminished by cocoa extract, and this effect was higher than that produced by equivalent concentrations of epicatechin but was lower than that produced by isoquercitrin. Interestingly, cocoa extract added prior to cell activation resulted in a significantly greater inhibition of TNFalpha secretion. Both cocoa extract and epicatechin decreased TNFalpha, interleukin (IL) 1alpha, and IL-6 mRNA expression, suggesting that their inhibitory effect on cytokine secretion is produced, in part, at the transcriptional level. Cocoa extract also significantly decreased NO secretion in a dose-dependent manner and with a greater effect than that produced by epicatechin. In conclusion, our study shows that cocoa flavonoids not only inhibit NO release from macrophages but also down-regulate inflammatory cytokines and chemokines.

Influence of hyaluronic acid on bacterial and fungal species, including clinically relevant opportunistic pathogens.

PubMed

Ardizzoni, Andrea; Neglia, Rachele G; Baschieri, Maria C; Cermelli, Claudio; Caratozzolo, Manuela; Righi, Elena; Palmieri, Beniamino; Blasi, Elisabetta

2011-10-01

Hyaluronic acid (HA) has several clinical applications (aesthetic surgery, dermatology, orthopaedics and ophtalmology). Following recent evidence, suggesting antimicrobial and antiviral properties for HA, we investigated its effects on 15 ATCC strains, representative of clinically relevant bacterial and fungal species. The in vitro system employed allowed to assess optical density of broth cultures as a measure of microbial load in a time-dependent manner. The results showed that different microbial species and, sometimes, different strains belonging to the same species, are differently affected by HA. In particular, staphylococci, enterococci, Streptococcus mutans, two Escherichia coli strains, Pseudomonas aeruginosa, Candida glabrata and C. parapsilosis displayed a HA dose-dependent growth inhibition; no HA effects were detected in E. coli ATCC 13768 and C. albicans; S. sanguinis was favoured by the highest HA dose. Therefore, the influence of HA on bacteria and fungi warrants further studies aimed at better establishing its relevance in clinical applications.

Erufosine simultaneously induces apoptosis and autophagy by modulating the Akt-mTOR signaling pathway in oral squamous cell carcinoma.

PubMed

Kapoor, Vaishali; Zaharieva, Maya M; Das, Satya N; Berger, Martin R

2012-06-01

We investigated the anticancer activity of erufosine in oral squamous carcinoma cell lines in terms of cell proliferation, colony formation, induction of autophagy/apoptosis, cell cycle and mTOR signaling pathway. Erufosine showed dose-dependent cytotoxicity in all cell lines, it induced autophagy as well as apoptosis, G2 cell cycle arrest and modulation of cyclin D1 expression. Further erufosine downregulated the phosphorylation of major components of mTOR pathway, like p-Akt at Ser473 and Thr308 residues, p-Raptor, p-mTOR, p-PRAS40 and its downstream substrates p-p70S6K and p-4EBP1 in a dose-dependent manner. The pre-treatment of tumor cells with p-mTOR siRNA increased cytotoxic effects of erufosine comparable to cisplatin but higher than rapamycin. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Dexamethasone Enhances 1α,25-Dihydroxyvitamin D3 Effects by Increasing Vitamin D Receptor Transcription*

PubMed Central

Hidalgo, Alejandro A.; Deeb, Kristin K.; Pike, J. Wesley; Johnson, Candace S.; Trump, Donald L.

2011-01-01

Calcitriol, the active form of vitamin D, in combination with the glucocorticoid dexamethasone (Dex) has been shown to increase the antitumor effects of calcitriol in squamous cell carcinoma. In this study we found that pretreatment with Dex potentiates calcitriol effects by inhibiting cell growth and increasing vitamin D receptor (VDR) and VDR-mediated transcription. Treatment with actinomycin D inhibits Vdr mRNA synthesis, indicating that Dex regulates VDR expression at transcriptional level. Real time PCR shows that treatment with Dex increases Vdr transcripts in a time- and a dose-dependent manner, indicating that Dex directly regulates expression of Vdr. RU486, an inhibitor of glucocorticoids, inhibits Dex-induced Vdr expression. In addition, the silencing of glucocorticoid receptor (GR) abolishes the induction of Vdr by Dex, indicating that Dex increases Vdr transcripts in a GR-dependent manner. A fragment located 5.2 kb upstream of Vdr transcription start site containing two putative glucocorticoid response elements (GREs) was evaluated using a luciferase-based reporter assay. Treatment with 100 nm Dex induces transcription of luciferase driven by the fragment. Deletion of the GRE distal to transcription start site was sufficient to abolish Dex induction of luciferase. Also, chromatin immunoprecipitation reveals recruitment of GR to distal GRE with Dex treatment. We conclude that Dex increases VDR and vitamin D effects by increasing Vdr de novo transcription in a GR-dependent manner. PMID:21868377

Analgesic activity of ZC88, a novel N-type voltage-dependent calcium channel blocker, and its modulation of morphine analgesia, tolerance and dependence.

PubMed

Meng, Ge; Wu, Ning; Zhang, Cheng; Su, Rui-Bin; Lu, Xin-Qiang; Liu, Yin; Yun, Liu-Hong; Zheng, Jian-Quan; Li, Jin

2008-05-31

ZC88 is a novel non-peptide N-type voltage-sensitive calcium channel blocker synthesized by our institute. In the present study, the oral analgesic activity of ZC88 in animal models of acute and neuropathic pain, and functional interactions between ZC88 and morphine in terms of analgesia, tolerance and dependence were investigated. In mice acetic acid writhing tests, ZC88 (10-80 mg/kg) administered by oral route showed significant antinociceptive effects in a dose-dependent manner. The ED50 values of ZC88 were 14.5 and 14.3 mg/kg in male and female mice, respectively. In sciatic nerve chronic constriction injury rats, mechanical allodynia was ameliorated by oral administration of ZC88 at doses of 14, 28 and 56 mg/kg, suggesting ZC88 relieved allodynic response of neuropathic pain. When concurrently administered with morphine, ZC88 (20-80 mg/kg) dose-dependently potentiated morphine analgesia and attenuated morphine analgesic tolerance in hot-plate tests. ZC88 also prevented chronic exposure to morphine-induced physical dependence and withdrawal, but not morphine-induced psychological dependence in conditioned place preference model. These results suggested that ZC88, a new non-peptide N-type calcium channel blocker, had notable oral analgesia and anti-allodynia for acute and neuropathic pain. ZC88 might be used in pain relief by either application alone or in combination with opioids because it enhanced morphine analgesia while prevented morphine-induced tolerance and physical dependence.

MAP30 promotes apoptosis of U251 and U87 cells by suppressing the LGR5 and Wnt/β-catenin signaling pathway, and enhancing Smac expression

PubMed Central

Jiang, Yilin; Miao, Junjie; Wang, Dongliang; Zhou, Jingru; Liu, Bo; Jiao, Feng; Liang, Jiangfeng; Wang, Yangshuo; Fan, Cungang; Zhang, Qingjun

2018-01-01

Significant antitumor activity of Momordica anti-human immunodeficiency virus protein of 30 kDa (MAP30) purified from Momordica charantia has been the subject of previous research. However, the effective mechanism of MAP30 on malignant glioma cells has not yet been clarified. The aim of the present study was to investigate the effects and mechanism of MAP30 on U87 and U251 cell lines. A Cell Counting Kit-8 assay, wound healing assay and Transwell assay were used to detect the effects on U87 and U251 cells treated with different concentrations of MAP30 (0.5, 1, 2, 4, 8 and 16 µM) over different periods of time. Proliferation, migration and invasion of each cell line were markedly inhibited by MAP30 in a dose- and time-dependent manner. Flow cytometry and fluorescence staining demonstrated that apoptosis increased and the cell cycle was arrested in S-phase in the two investigated cell lines following MAP30 treatment. Western blot analysis demonstrated that leucine-rich-repeat-containing G-protein-coupled receptor 5 (LGR5) expression and key proteins in the Wnt/β-catenin signaling pathway were apparently decreased, whereas second mitochondria-derived activator of caspase (Smac) protein expression significantly increased with MAP30 treatment in the same manner. These results suggest that MAP30 markedly induces apoptosis in U87 and U251 cell lines by suppressing LGR5 and the Wnt/β-catenin signaling pathway, and enhancing Smac expression in a dose- and time-dependent manner. PMID:29556310

Redox Signaling and Bioenergetics Influence Lung Cancer Cell Line Sensitivity to the Isoflavone ME-344.

PubMed

Manevich, Yefim; Reyes, Leticia; Britten, Carolyn D; Townsend, Danyelle M; Tew, Kenneth D

2016-08-01

ME-344 [(3R,4S)-3,4-bis(4-hydroxyphenyl)-8-methyl-3,4-dihydro-2H-chromen-7-ol] is a second-generation derivative natural product isoflavone presently under clinical development. ME-344 effects were compared in lung cancer cell lines that are either intrinsically sensitive or resistant to the drug and in primary immortalized human lung embryonic fibroblasts (IHLEF). Cytotoxicity at low micromolar concentrations occurred only in sensitive cell lines, causing redox stress, decreased mitochondrial ATP production, and subsequent disruption of mitochondrial function. In a dose-dependent manner the drug caused instantaneous and pronounced inhibition of oxygen consumption rates (OCR) in drug-sensitive cells (quantitatively significantly less in drug-resistant cells). This was consistent with targeting of mitochondria by ME-344, with specific effects on the respiratory chain (resistance correlated with higher glycolytic indexes). OCR inhibition did not occur in primary IHLEF. ME-344 increased extracellular acidification rates in drug-resistant cells (significantly less in drug-sensitive cells), implying that ME-344 targets mitochondrial proton pumps. Only in drug-sensitive cells did ME-344 dose-dependently increase the intracellular generation of reactive oxygen species and cause oxidation of total (mainly glutathione) and protein thiols and the concomitant immediate increases in NADPH levels. We conclude that ME-344 causes complex, redox-specific, and mitochondria-targeted effects in lung cancer cells, which differ in extent from normal cells, correlate with drug sensitivity, and provide indications of a beneficial in vitro therapeutic index. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Effects of naringin on the proliferation and osteogenic differentiation of human amniotic fluid-derived stem cells.

PubMed

Liu, Meimei; Li, Yan; Yang, Shang-Tian

2017-01-01

Human amniotic fluid-derived stem cells (hAFSCs) are a novel cell source for generating osteogenic cells to treat bone diseases. Effective induction of osteogenic differentiation from hAFSCs is critical to fulfil their therapeutic potential. In this study, naringin, the main active compound of Rhizoma drynariae (a Chinese herbal medicine), was used to stimulate the proliferation and osteogenic differentiation of hAFSCs. The results showed that naringin enhanced the proliferation and alkaline phosphatase activity (ALP) of hAFSCs in a dose-dependent manner in the range 1-100 µg/ml, while an inhibition effect was observed at 200 µg/ml. Consistently, the calcium content also increased with naringin concentration up to 100 µg/ml. The enhanced osteogenic differentiation of hAFSCs by naringin was further confirmed by the dose-dependent upregulation of marker genes, including osteopontin (OPN) and Collagen I from RT-PCR analysis. The increased osteoprotegerin (OPG) expression and minimal expression of receptor activator of nuclear factor-κB ligand (RANKL) suggested that naringin also inhibited osteoclastogenesis of hAFSCs. In addition, the gene expressions of bone morphogenetic protein 4 (BMP4), runt-related transcription factor 2 (RUNX2), β-catenin and Cyclin D1 also increased significantly, indicating that naringin promotes the osteogenesis of hAFSCs via the BMP and Wnt-β-catenin signalling pathways. These results suggested that naringin can be used to upregulate the osteogenic differentiation of hAFSCs, which could provide an attractive and promising treatment for bone disorders. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Randomised clinical trial: study of escalating doses of NRL001 given in rectal suppositories of different weights.

PubMed

Bell, D; Pediconi, C; Jacobs, A

2014-03-01

The application of α-adrenoceptor agonists can improve faecal incontinence symptoms. The aim of this study was to investigate the pharmacokinetic and systemic effects of NRL001 administered as different strengths in 1 or 2 g suppositories. This randomised, double-blind, placebo controlled study included 48 healthy subjects. Group 1 consisted of two cohorts of 12 subjects administered either four single doses of 1 or 2 g rectal suppository with either 5, 7.5 or 10 mg NRL001, or matching placebo. Group 2 consisted of two cohorts of 12 subjects administered either four single doses of 1 or 2 g rectal suppository with either 10, 12.5 or 15 mg NRL001, or matching placebo. Doses were given in an escalating manner with placebo at a random position within the sequence. Tmax was at ~4.5 h post-dose for all NRL001 doses. Median AUC0-tz , AUC0-∞ and Cmax increased with increasing dose for both suppository sizes. The estimate of ratios of geometric means comparing 2 g with 1 g suppository, and regression analysis for dose proportionality, was close to 1 for the variables AUC0-tz , AUC0-∞ and Cmax (P > 0.05). For both suppository sizes, 20-min mean pulse rate was significantly decreased compared with placebo with all doses (P < 0.05). Blood pressure decreased overall. There were 144 adverse events (AEs) and no serious AEs reported during the study. All AEs were mild in severity. The regression analysis concluded that the doses were dose proportional. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

Bombesin stimulates invasion and migration of Isreco1 colon carcinoma cells in a Rho-dependent manner.

PubMed

Saurin, Jean-Christophe; Fallavier, Marjorie; Sordat, Bernard; Gevrey, Jean-Claude; Chayvialle, Jean-Alain; Abello, Jacques

2002-08-15

The membrane receptor for the neuropeptide bombesin/gastrin-releasing peptide (GRP) is expressed by a large fraction of human colorectal carcinoma cells. We reported previously a stimulation of cell adhesion and lamellipodia formation by the neuropeptide bombesin in the human, bombesin/GRP receptor-expressing, Isreco1 colorectal cancer cell line (J. C. Saurin et al., Cancer Res., 59: 962-967, 1999). Using invasion and motility assays, we demonstrate in this report that bombesin can both enhance the invasive capacity of Isreco1 cells in a dose-dependent manner (maximal effect at 1 nM) and stimulate the closure of wounds performed on confluent Isreco1 cells. These effects were reversed fully by the specific bombesin/GRP receptor antagonist D-Phe(6)-Bn(6-13)OMe used at 1 micro M. MMP-9 and urokinase-type plasminogen activator were expressed by Isreco1 cells, and bombesin did not significantly alter their level of secretion. Interestingly, exoenzyme C3 (10 micro g/ml) decreased cell invasiveness induced by bombesin by 70% and completely inhibited the migration of Isreco1 cells. Similarly, the Rho-kinase inhibitor Y-27632 dose-dependently reduced the effect of bombesin on cell invasion. Moreover, pull-down assays for GTP-bound RhoA demonstrated that bombesin was able to activate the small G-protein in Isreco1 cells. These results show that the neuropeptide bombesin is able to modulate invasiveness of Isreco1 colorectal carcinoma cells in vitro through a Rho-dependent pathway, leading to an increase in cell locomotion without a significant effect on tumor-cell associated proteolytic activity. These findings indicate that bombesin/GRP receptor expression may contribute to the cellular events that are critical for invasion/migration of colorectal carcinoma cells.

A consistent two-mutation model of bone cancer for two data sets of radium-injected beagles.

PubMed

Bijwaard, H; Brugmans, M J P; Leenhouts, H P

2002-09-01

A two-mutation carcinogenesis model has been applied to model osteosarcoma incidence in two data sets of beagles injected with 226Ra. Taking age-specific retention into account, the following results have been obtained: (1) a consistent and well-fitting solution for all age and dose groups, (2) mutation rates that are linearly dependent on dose rate, with an exponential decrease for the second mutation at high dose rates, (3) a linear-quadratic dose-effect relationship, which indicates that care should be taken when extrapolating linearly, (4) highest cumulative incidences for injection at young adult age, and highest risks for injection doses of a few kBq kg(-1) at these ages, and (5) when scaled appropriately, the beagle model compares fairly well with a description for radium dial painters, suggesting that a consistent model description of bone cancer induction in beagles and humans may be possible.

Transferring mixtures of chemicals from sediment to a bioassay using silicone-based passive sampling and dosing.

PubMed

Mustajärvi, Lukas; Eriksson-Wiklund, Ann-Kristin; Gorokhova, Elena; Jahnke, Annika; Sobek, Anna

2017-11-15

Environmental mixtures of chemicals consist of a countless number of compounds with unknown identity and quantity. Yet, chemical regulation is mainly built around the assessment of single chemicals. Existing frameworks for assessing the toxicity of mixtures require that both the chemical composition and quantity are known. Quantitative analyses of the chemical composition of environmental mixtures are however extremely challenging and resource-demanding. Bioassays may therefore serve as a useful approach for investigating the combined toxicity of environmental mixtures of chemicals in a cost-efficient and holistic manner. In this study, an unknown environmental mixture of bioavailable semi-hydrophobic to hydrophobic chemicals was sampled from a contaminated sediment in a coastal Baltic Sea area using silicone polydimethylsiloxane (PDMS) as an equilibrium passive sampler. The chemical mixture was transferred to a PDMS-based passive dosing system, and its applicability was demonstrated using green algae Tetraselmis suecica in a cell viability assay. The proportion of dead cells increased significantly with increasing exposure level and in a dose-response manner. At an ambient concentration, the proportion of dead cells in the population was nearly doubled compared to the control; however, the difference was non-significant due to high inter-replicate variability and a low number of replicates. The validation of the test system regarding equilibrium sampling, loading efficiency into the passive dosing polymer, stability of the mixture composition, and low algal mortality in control treatments demonstrates that combining equilibrium passive sampling and passive dosing is a promising tool for investigating the toxicity of bioavailable semi-hydrophobic and hydrophobic chemicals in complex environmental mixtures.

The Inhibitory Effect of Ciprofloxacin on the β-Glucuronidase-mediated Deconjugation of the Irinotecan Metabolite SN-38-G.

PubMed

Kodawara, Takaaki; Higashi, Takashi; Negoro, Yutaka; Kamitani, Yukio; Igarashi, Toshiaki; Watanabe, Kyohei; Tsukamoto, Hitoshi; Yano, Ryoichi; Masada, Mikio; Iwasaki, Hiromichi; Nakamura, Toshiaki

2016-05-01

The enterohepatic recycling of a drug consists of its biliary excretion and intestinal reabsorption, which is sometimes accompanied by hepatic conjugation and intestinal deconjugation reactions. β-Glucuronidase, an intestinal bacteria-produced enzyme, can break the bond between a biliary excreted drug and glucuronic acid. Antibiotics such as ciprofloxacin can reduce the enterohepatic recycling of glucuronide-conjugated drugs. In this study, we established an in vitro system to evaluate the β-glucuronidase-mediated deconjugation of the irinotecan metabolite SN-38-G to its active SN-38 form and the effect of ciprofloxacin thereon. SN-38 formation increased in a time-dependent manner from 5 to 30 min. in the presence of β-glucuronidase. Ciprofloxacin and phenolphthalein-β-D-glucuronide (PhePG), a typical β-glucuronidase substrate, significantly decreased SN-38-G deconjugation and, hence SN-38 formation. Similarly, the antibiotics enoxacin and gatifloxacin significantly inhibited the conversion of SN-38-G to SN-38, which was not observed for levofloxacin, streptomycin, ampicillin and amoxicillin/clavulanate. Ciprofloxacin showed a dose-dependent inhibitory effect on the β-glucuronidase-mediated conversion of SN-38-G to SN-38 with a half-maximal inhibitory concentration (IC50 ) value of 83.8 μM. PhePG and ciprofloxacin afforded the inhibition in a competitive and non-competitive manner, respectively. These findings suggest that the reduction in the serum SN-38 concentration following co-administration of ciprofloxacin during irinotecan treatment is due, at least partly, to the decreased enterohepatic circulation of SN-38 through the non-competitive inhibition of intestinal β-glucuronidase-mediated SN-38-G deconjugation. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Efficiency of photodynamic therapy using indocyanine green and infrared light on MCF-7 breast cancer cells in vitro

NASA Astrophysics Data System (ADS)

Ruhi, Mustafa K.; Ak, Ayşe.; Gülsoy, Murat

2016-03-01

Cancer is one of the main reasons of death in all around the world. The main treatments of cancer include surgical intervention, radiation therapy and chemotherapy. These treatments can be applied separately or in a combined manner. Another therapeutic method that is still being researched and recently has started to be used in clinical applications is Photodynamic Therapy (PDT). Most photosensitizers currently being investigated are sensitive to red light. However, it is known that infrared light has a better penetration into the skin or tissue. Indocyanine Green (ICG), which is used in this study, is sensitive to infrared light. The aim of this in vitro study is to investigate the effect of PDT on breast cancer cells by using different doses of ICG and infrared light irradiation. 25, 50 and 100 μM ICG concentrations and 25 and 50 J/cm2 laser energy doses were applied to MCF-7 cell lines. MTT analyses were performed on 24, 48 and 72 hours following the treatments. As a result, inhibition of cell viability was observed in a time and dose dependent manner. It can be concluded that ICG-PDT application is a good alternative to conventional radiation therapy and chemotherapy for breast cancer treatment.

Leucine facilitates insulin signaling through a Gαi protein-dependent signaling pathway in hepatocytes.

PubMed

Yang, Xuefeng; Mei, Shuang; Wang, Xiaolei; Li, Xiang; Liu, Rui; Ma, Yan; Hao, Liping; Yao, Ping; Liu, Liegang; Sun, Xiufa; Gu, Haihua; Liu, Zhenqi; Cao, Wenhong

2013-03-29

In this study, we addressed the direct effect of leucine on insulin signaling. In investigating the associated mechanisms, we found that leucine itself does not activate the classical Akt- or ERK1/2 MAP kinase-dependent signaling pathways but can facilitate the insulin-induced phosphorylations of Akt(473) and ERK1/2 in a time- and dose-dependent manner in cultured hepatocytes. The leucine-facilitated insulin-induced phosphorylation of Akt at residue 473 was not affected by knocking down the key component of mTORC1 or -2 complexes but was blocked by inhibition of c-Src (PP2), PI3K (LY294002), Gαi protein (pertussis toxin or siRNA against Gαi1 gene, or β-arrestin 2 (siRNA)). Similarly, the leucine-facilitated insulin activation of ERK1/2 was also blunted by pertussis toxin. We further show that leucine facilitated the insulin-mediated suppression of glucose production and expression of key gluconeogenic genes in a Gαi1 protein-dependent manner in cultured primary hepatocytes. Together, these results show that leucine can directly facilitate insulin signaling through a Gαi protein-dependent intracellular signaling pathway. This is the first evidence showing that macronutrients like amino acid leucine can facilitate insulin signaling through G proteins directly.

Leucine Facilitates Insulin Signaling through a Gαi Protein-dependent Signaling Pathway in Hepatocytes*

PubMed Central

Yang, Xuefeng; Mei, Shuang; Wang, Xiaolei; Li, Xiang; Liu, Rui; Ma, Yan; Hao, Liping; Yao, Ping; Liu, Liegang; Sun, Xiufa; Gu, Haihua; Liu, Zhenqi; Cao, Wenhong

2013-01-01

In this study, we addressed the direct effect of leucine on insulin signaling. In investigating the associated mechanisms, we found that leucine itself does not activate the classical Akt- or ERK1/2 MAP kinase-dependent signaling pathways but can facilitate the insulin-induced phosphorylations of Akt473 and ERK1/2 in a time- and dose-dependent manner in cultured hepatocytes. The leucine-facilitated insulin-induced phosphorylation of Akt at residue 473 was not affected by knocking down the key component of mTORC1 or -2 complexes but was blocked by inhibition of c-Src (PP2), PI3K (LY294002), Gαi protein (pertussis toxin or siRNA against Gαi1 gene, or β-arrestin 2 (siRNA)). Similarly, the leucine-facilitated insulin activation of ERK1/2 was also blunted by pertussis toxin. We further show that leucine facilitated the insulin-mediated suppression of glucose production and expression of key gluconeogenic genes in a Gαi1 protein-dependent manner in cultured primary hepatocytes. Together, these results show that leucine can directly facilitate insulin signaling through a Gαi protein-dependent intracellular signaling pathway. This is the first evidence showing that macronutrients like amino acid leucine can facilitate insulin signaling through G proteins directly. PMID:23404499

Psilocybin dose-dependently causes delayed, transient headaches in healthy volunteers

PubMed Central

Johnson, Matthew W.; Sewell, R. Andrew; Griffiths, Roland R.

2011-01-01

Background Psilocybin is a well-characterized classic hallucinogen (psychedelic) with a long history of religious use by indigenous cultures, and nonmedical use in modern societies. Although psilocybin is structurally related to migraine medications, and case studies suggest that psilocybin may be efficacious in treatment of cluster headache, little is known about the relationship between psilocybin and headache. Methods This double-blind study examined a broad range of psilocybin doses (0, 5, 10, 20, and 30 mg/70 kg) on headache in 18 healthy participants. Results Psilocybin frequently caused headache, the incidence, duration, and severity of which increased in a dose-dependent manner. All headaches had delayed onset, were transient, and lasted no more than a day after psilocybin administration. Conclusions Possible mechanisms for these observations are discussed, and include induction of delayed headache through nitric oxide release. These data suggest that headache is an adverse event to be expected with the nonmedical use of psilocybin-containing mushrooms as well as the administration of psilocybin in human research. Headaches were neither severe nor disabling, and should not present a barrier to future psilocybin research. PMID:22129843

Psilocybin dose-dependently causes delayed, transient headaches in healthy volunteers.

PubMed

Johnson, Matthew W; Sewell, R Andrew; Griffiths, Roland R

2012-06-01

Psilocybin is a well-characterized classic hallucinogen (psychedelic) with a long history of religious use by indigenous cultures, and nonmedical use in modern societies. Although psilocybin is structurally related to migraine medications, and case studies suggest that psilocybin may be efficacious in treatment of cluster headache, little is known about the relationship between psilocybin and headache. This double-blind study examined a broad range of psilocybin doses (0, 5, 10, 20, and 30 mg/70 kg) on headache in 18 healthy participants. Psilocybin frequently caused headache, the incidence, duration, and severity of which increased in a dose-dependent manner. All headaches had delayed onset, were transient, and lasted no more than a day after psilocybin administration. Possible mechanisms for these observations are discussed, and include induction of delayed headache through nitric oxide release. These data suggest that headache is an adverse event to be expected with the nonmedical use of psilocybin-containing mushrooms as well as the administration of psilocybin in human research. Headaches were neither severe nor disabling, and should not present a barrier to future psilocybin research. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Drosophila melanogaster Natural Variation Affects Growth Dynamics of Infecting Listeria monocytogenes

PubMed Central

Hotson, Alejandra Guzmán; Schneider, David S.

2015-01-01

We find that in a Listeria monocytogenes/Drosophila melanogaster infection model, L. monocytogenes grows according to logistic kinetics, which means we can measure both a maximal growth rate and growth plateau for the microbe. Genetic variation of the host affects both of the pathogen growth parameters, and they can vary independently. Because growth rates and ceilings both correlate with host survival, both properties could drive evolution of the host. We find that growth rates and ceilings are sensitive to the initial infectious dose in a host genotype–dependent manner, implying that experimental results differ as we change the original challenge dose within a single strain of host. PMID:26438294

Benzodiazepine sensitivity in normal human subjects.

PubMed

Hommer, D W; Matsuo, V; Wolkowitz, O; Chrousos, G; Greenblatt, D J; Weingartner, H; Paul, S M

1986-06-01

Increasing intravenous doses of diazepam or placebo were administered to ten healthy normal volunteers, and the changes in saccadic eye velocity, self-rated sedation and anxiety, and plasma cortisol and growth hormone concentrations were measured. Diazepam administration (4.4 to 140 micrograms/kg, cumulative dose) resulted in a dose-dependent decrease in saccadic eye velocity and plasma cortisol level as well as a dose-dependent increase in self-rated sedation and plasma growth hormone level. Self-rated anxiety was unaffected in these relatively nonanxious subjects. The diazepam-induced changes in saccadic eye velocity, sedation, and growth hormone and cortisol levels were highly correlated with each other and with increasing plasma diazepam concentration. These results are consistent with a benzodiazepine receptor-mediated action of diazepam. The highly quantifiable and dose-dependent decrease in saccadic eye velocity by benzodiazepines should make this a useful measure of benzodiazepine receptor sensitivity in humans.

A pharmacokinetic/viral kinetic model to evaluate the treatment effectiveness of danoprevir against chronic HCV

PubMed Central

Canini, Laetitia; Chatterjee, Anushree; Guedj, Jeremie; Lemenuel-Diot, Annabelle; Brennan, Barbara; Smith, Patrick F; Perelson, Alan S

2014-01-01

Background Viral kinetic models have proven useful to characterize treatment effectiveness during HCV therapy with interferon (IFN) or with direct acting antivirals (DAAs). Methods We use a pharmacokinetic/viral kinetic (PK/VK) model to describe HCV RNA kinetics during treatment with danoprevir, a protease inhibitor. In a phase 1 study, danoprevir monotherapy was administered for 14 days in ascending doses ranging from 200 to 600 mg per day to 40 patients of whom 32 were treatment-naïve and 8 were non-responders to prior PEG-IFN-α/ribavirin treatment. Results In most patients, a biphasic decline of HCV RNA during therapy was observed. A two-compartment PK model and a VK model that considered treatment effectiveness to vary with the predicted danoprevir concentration inside the second compartment provided a good fit to the viral load data. A time-varying effectiveness model was also used to fit the viral load data. The antiviral effectiveness increased in a dose-dependent manner, with a 14-day time-averaged effectiveness of 0.95 at the lowest dose (100 mg bid) and 0.99 at the highest dose (200 mg tid). Prior IFN non-responders exhibited a 14-day time-averaged effectiveness of 0.98 (300 mg bid). The second phase decline showed two different behaviors, with 30% of patients exhibiting a rapid decline of HCV RNA, comparable to that seen with other protease inhibitors (>0.3 d−1), whereas the viral decline was slower in the other patients. Conclusions Our results are consistent with the modest SVR rates from the INFORM-SVR study where patients were treated with a combination of mericitabine and ritonavir-boosted danoprevir. PMID:25321394

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

Canini, Laetitia; Chatterjee, Anushree; Guedj, Jeremie

Background—Viral kinetic models have proven useful to characterize treatment effectiveness during HCV therapy with interferon (IFN) or with direct acting antivirals (DAAs). Methods—We use a pharmacokinetic/viral kinetic (PK/VK) model to describe HCV RNA kinetics during treatment with danoprevir, a protease inhibitor. In a phase 1 study, danoprevir monotherapy was administered for 14 days in ascending doses ranging from 200 to 600 mg per day to 40 patients of whom 32 were treatment-naïve and 8 were non-responders to prior PEG-IFN-α/ribavirin treatment. Results—In most patients, a biphasic decline of HCV RNA during therapy was observed. A two-compartment PK model and a VKmore » model that considered treatment effectiveness to vary with the predicted danoprevir concentration inside the second compartment provided a good fit to the viral load data. A time-varying effectiveness model was also used to fit the viral load data. We found the antiviral effectiveness increased in a dose-dependent manner, with a 14-day time-averaged effectiveness of 0.95 at the lowest dose (100 mg bid) and 0.99 at the highest dose (200 mg tid). Prior IFN non-responders exhibited a 14-day time-averaged effectiveness of 0.98 (300 mg bid). Finally, the second phase decline showed two different behaviors, with 30% of patients exhibiting a rapid decline of HCV RNA, comparable to that seen with other protease inhibitors (>0.3 d-1), whereas the viral decline was slower in the other patients. Conclusions—Our results are consistent with the modest SVR rates from the INFORM-SVR study where patients were treated with a combination of mericitabine and ritonavir-boosted danoprevir.« less

A pharmacokinetic/viral kinetic model to evaluate the treatment effectiveness of danoprevir against chronic HCV

DOE PAGES

Canini, Laetitia; Chatterjee, Anushree; Guedj, Jeremie; ...

2014-10-16

Background—Viral kinetic models have proven useful to characterize treatment effectiveness during HCV therapy with interferon (IFN) or with direct acting antivirals (DAAs). Methods—We use a pharmacokinetic/viral kinetic (PK/VK) model to describe HCV RNA kinetics during treatment with danoprevir, a protease inhibitor. In a phase 1 study, danoprevir monotherapy was administered for 14 days in ascending doses ranging from 200 to 600 mg per day to 40 patients of whom 32 were treatment-naïve and 8 were non-responders to prior PEG-IFN-α/ribavirin treatment. Results—In most patients, a biphasic decline of HCV RNA during therapy was observed. A two-compartment PK model and a VKmore » model that considered treatment effectiveness to vary with the predicted danoprevir concentration inside the second compartment provided a good fit to the viral load data. A time-varying effectiveness model was also used to fit the viral load data. We found the antiviral effectiveness increased in a dose-dependent manner, with a 14-day time-averaged effectiveness of 0.95 at the lowest dose (100 mg bid) and 0.99 at the highest dose (200 mg tid). Prior IFN non-responders exhibited a 14-day time-averaged effectiveness of 0.98 (300 mg bid). Finally, the second phase decline showed two different behaviors, with 30% of patients exhibiting a rapid decline of HCV RNA, comparable to that seen with other protease inhibitors (>0.3 d-1), whereas the viral decline was slower in the other patients. Conclusions—Our results are consistent with the modest SVR rates from the INFORM-SVR study where patients were treated with a combination of mericitabine and ritonavir-boosted danoprevir.« less

Local delivery of rapamycin: a toxicity and efficacy study in an experimental malignant glioma model in rats

PubMed Central

Tyler, Betty; Wadsworth, Scott; Recinos, Violette; Mehta, Vivek; Vellimana, Ananth; Li, Khan; Rosenblatt, Joel; Do, Hiep; Gallia, Gary L.; Siu, I-Mei; Wicks, Robert T.; Rudek, Michelle A.; Zhao, Ming; Brem, Henry

2011-01-01

Rapamycin, an anti-proliferative agent, is effective in the treatment of renal cell carcinoma and recurrent breast cancers. We proposed that this potent mammalian target of rapamycin inhibitor may be useful for the treatment of gliomas as well. We examined the cytotoxicity of rapamycin against a rodent glioma cell line, determined the toxicity of rapamycin when delivered intracranially, and investigated the efficacy of local delivery of rapamycin for the treatment of experimental malignant glioma in vivo. We also examined the dose-dependent efficacy of rapamycin and the effect when locally delivered rapamycin was combined with radiation therapy. Rapamycin was cytotoxic to 9L cells, causing 34% growth inhibition at a concentration of 0.01 µg/mL. No in vivo toxicity was observed when rapamycin was incorporated into biodegradable caprolactone-glycolide (35:65) polymer beads at 0.3%, 3%, and 30% loading doses and implanted intracranially. Three separate efficacy studies were performed to test the reproducibility of the effect of the rapamycin beads as well as the validity of this treatment approach. Animals treated with the highest dose of rapamycin beads tested (30%) consistently demonstrated significantly longer survival durations than the control and placebo groups. All dose-escalating rapamycin bead treatment groups (0.3%, 3% and 30%), treated both concurrently with tumor and in a delayed manner after tumor placement, experienced a significant increase in survival, compared with controls. Radiation therapy in addition to the simultaneous treatment with 30% rapamycin beads led to significantly longer survival duration than either therapy alone. These results suggest that the local delivery of rapamycin for the treatment of gliomas should be further investigated. PMID:21727209

Chlordecone, a mixed pregnane X receptor (PXR) and estrogen receptor alpha (ERα) agonist, alters cholesterol homeostasis and lipoprotein metabolism in C57BL/6 mice

PubMed Central

Lee, Junga; Scheri, Richard C.; Zhang, Yuan; Curtis, Lawrence R.

2008-01-01

Chlordecone (CD) is one of many banned organochlorine (OC) insecticides that are widespread persistent organic pollutants. OC insecticides alter lipid homeostasis in rodents at doses that are not neurotoxic or carcinogenic. Pretreatment of mice or rats with CD altered tissue distribution of a subsequent dose of [14C]CD or [14C]cholesterol (CH). Nuclear receptors regulate expression of genes important in the homeostasis of CH and other lipids. In this study, we report that CD suppresses in vitro reporter systems for human liver X receptors (LXRs) and activates those for human farnesoid X receptor (FXR), pregnane X receptor (PXR) and estrogen receptor α (ERα) in a concentration-dependent manner (0–50 μM). Consistent with human PXR activation in vitro, three days after a single dose of CD (15 mg/kg) hepatic microsomal CYP3A11 protein increases in C57BL/6 mice. CD decreases hepatic CH ester content without altering total CH concentration. Apolipoprotein A-I (apoA-I) contents of hepatic lipoprotein-rich and microsomal fractions of CD-treated mice are higher than controls. There is a significant reduction in non-high density lipoprotein CH but not apolipoprotein B-48/100 (apoB-48/100) in plasma from CD-treated mice after a 4 h fast. At 14 days after 15 mg CD/kg apoA-I and apoB-100 proteins but not CYP3A11 protein in hepatic microsomes are similar to controls. This work indicates that altered CH homeostasis is a mode of OC insecticide action of relevance after a single dose. This at least partially explains altered CH tissue distribution in CD-pretreated mice. PMID:18789348

Lemna minor plants chronically exposed to ionising radiation: RNA-seq analysis indicates a dose rate dependent shift from acclimation to survival strategies.

PubMed

Van Hoeck, Arne; Horemans, Nele; Nauts, Robin; Van Hees, May; Vandenhove, Hildegarde; Blust, Ronny

2017-04-01

Ecotoxicological research provides knowledge on ionising radiation-induced responses in different plant species. However, the sparse data currently available are mainly extracted from acute exposure treatments. To provide a better understanding of environmental exposure scenarios, the response to stress in plants must be followed in more natural relevant chronic conditions. We previously showed morphological and biochemical responses in Lemna minor plants continuously exposed for 7days in a dose-rate dependent manner. In this study responses on molecular (gene expression) and physiological (photosynthetic) level are evaluated in L. minor plants exposed to ionising radiation. To enable this, we examined the gene expression profiles of irradiated L. minor plants by using an RNA-seq approach. The gene expression data reveal indications that L. minor plants exposed at lower dose rates, can tolerate the exposure by triggering acclimation responses. In contrast, at the highest dose rate tested, a high number of genes related to antioxidative defense systems, DNA repair and cell cycle were differentially expressed suggesting that only high dose rates of ionising radiation drive L. minor plants into survival strategies. Notably, the photosynthetic process seems to be unaffected in L. minor plants among the tested dose rates. This study, supported by our earlier work, clearly indicates that plants shift from acclimation responses towards survival responses at increasing dose rates of ionising radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

Metabolites and JAK/STAT pathway were involved in the liver and spleen damage in male Wistar rats fed with mequindox.

PubMed

Wang, Xu; Huang, Xian-Ju; Ihsan, Awais; Liu, Zhao-Ying; Huang, Ling-Li; Zhang, Hua-Hai; Zhang, Hong-Fei; Zhou, Wen; Liu, Qin; Xue, Xi-Juan; Yuan, Zong-Hui

2011-02-27

Mequindox (MEQ) is a novel synthetic quinoxaline 1,4-dioxides antibacterial agent and growth promoter in animal husbandry. This study was to investigate whether reactive oxygen species (ROS), the Janus kinase-signal transducer and activator of transcription (JAK/STAT) pathway, suppressors of cytokine signaling (SOCS) and inflammatory cytokines were involved in toxicities of MEQ. Our data demonstrated that high dose of MEQ (275 mg/kg) apparently led to tissue impairment combined with imbalance of redox in liver. In liver and spleen samples, hydroxylation metabolites and desoxymequindox were detected, directly confirming the potential link of N→O group reduction metabolism with its organ toxicity. Moreover, up-regulation of JAK/STAT, SOCS family, tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) were also observed in the high-dose group. Meanwhile, significant changes of oxidative stress indices in liver were observed in the high-dose group. As for NADPH subunit, the mRNA levels of many subunits were significantly up-regulated at low doses but down-regulated in a dose-dependent manner in liver and spleen, suggesting an involvement of NADPH in MEQ metabolism and ROS generation. In conclusion, we reported the dose-dependent long-term toxicity as well as the discussion of the potential mechanism and pathways of MEQ, which raised further awareness of its toxicity following with the dose change. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Involvement of opioid peptides in the regulation of reproduction in the prawn Penaeus indicus

NASA Astrophysics Data System (ADS)

Sreenivasula Reddy, P.

The possible involvement of an endogenous opioid system in the regulation of ovarian development in the prawn Penaeus indicus was investigated. Injection of leucine-enkephalin significantly increased the ovarian index and oocyte diameter in a dose-dependent manner. In contrast, injection of methionine-enkephalin significantly decreased the ovarian index and oocyte diameters. These results provide evidence to support the hypothesis that an opioid system is involved in the regulation of reproduction in crustaceans.

Inhibition by sodium nitroprusside of the expression of inducible nitric oxide synthase in rat neutrophils.

PubMed Central

Mariotto, S; Cuzzolin, L; Adami, A; Del Soldato, P; Suzuki, H; Benoni, G

1995-01-01

A well-known nitric oxide (NO)-releasing compound, sodium nitroprusside (SNP), decreases in a dose-dependent manner NO synthase (NOS) activity induced in rat neutrophils by treatment with lipopolysaccharide (LPS). This inhibitory action of SNP seems not to be due to its direct effect on the enzyme activity. The strong nitrosonium ion (NO+) character of SNP could be responsible for its inhibition of NOS induction in neutrophils. PMID:7542530

A cytotoxic serine proteinase isolated from mouse submandibular gland.

PubMed

Shimamura, T; Nagumo, N; Ikigai, H; Murakami, K; Okubo, S; Toda, M; Ohnishi, R; Tomita, M

1989-08-01

We have isolated a novel cytotoxic factor from the submandibular glands of male BALB/c mice by Sephadex G-50 gel filtration chromatography and reverse-phase HPLC. The cytotoxic factor is a serine proteinase, which belongs to the mouse glandular kallikrein (mGK) family, with an Mr of approximately 27,000. The purified serine proteinase showed cytotoxic activity against mouse thymocytes in a dose-dependent manner, and a serine proteinase inhibitor, diisopropyl fluorophosphate, blocked its cytotoxic activity.

Somatostatin, prostaglandin E2 and atropine inhibition of the gastric actions of bombesin in the dog.

PubMed

Hirschowitz, B I; Molina, E

1984-01-01

Bombesin, acetylcholine, prostaglandins and somatostatin are all thought to be involved in the regulation of gastrin release and gastric secretion. We have studied the effects of low doses of atropine, 16-16(Me)2-prostaglandin E2 (PGE2) and somatostatin-14 on bombesin-stimulated gastrin release and gastric acid and pepsin secretion in conscious fistula dogs. For reference, synthetic gastrin G-17 was studied with and without somatostatin. Bombesin, in a dose-related manner, increased serum gastrin, which in turn stimulated gastric acid and pepsin secretion in a serum gastrin, concentration-dependent manner. Somatostatin inhibited gastrin release by bombesin as well as the secretory stimulation by G-17; the combination of sequential effects resulted in a marked inhibition of bombesin-stimulated gastric acid and pepsin secretion. PGE2 also strongly inhibited gastrin release and acid and pepsin secretion. Atropine had no significant effect on gastrin release, but greatly inhibited gastric secretion. Thus somatostatin and PGE2 inhibited at two sites, gastrin release and gastrin effects, while atropine affected only the latter.

Intravesical application of rebamipide suppresses bladder inflammation in a rat cystitis model.

PubMed

Funahashi, Yasuhito; Yoshida, Masaki; Yamamoto, Tokunori; Majima, Tsuyoshi; Takai, Shun; Gotoh, Momokazu

2014-04-01

We examined the effects of intravesical application of rebamipide (Otsuka Pharmaceutical, Tokyo, Japan) on bladder inflammation and overactivity in a chemically induced cystitis model. Female Sprague Dawley® rats under isoflurane anesthesia were injected with 150 mg/kg cyclophosphamide in the peritoneum, and 1 mM or 10 mM rebamipide or vehicle was administered in the bladder and remained for 1 hour. Control rats were injected with saline in the peritoneum and vehicle was administered in the bladder. The bladder was harvested at 48 hours. Hematoxylin and eosin staining was performed and the inflammation grade was assessed. The amount of myeloperoxidase was measured using enzyme-linked immunosorbent assay. Proinflammatory cytokines were quantified using reverse transcriptase-polymerase chain reaction. Cystometrogram was done in awake rats 48 hours after cyclophosphamide treatment to measure voiding reflex parameters. Histological evaluation revealed that bladder inflammation in cyclophosphamide treated rats was suppressed by rebamipide in a dose dependent manner. Up-regulated myeloperoxidase, IL-1β, IL-6 and TNF-α expression in cyclophosphamide treated rats was also suppressed in rebamipide treated rats. Cystometrogram demonstrated that the intercontraction interval decreased in cyclophosphamide treated rats but was prolonged by rebamipide. Intravesical application of rebamipide suppressed bladder inflammation and overactivity in a dose dependent manner. This may provide a new treatment strategy for chemotherapy associated cystitis. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Transgenic expression of an unedited mitochondrial orfB gene product from wild abortive (WA) cytoplasm of rice (Oryza sativa L.) generates male sterility in fertile rice lines.

PubMed

Chakraborty, Anirban; Mitra, Joy; Bhattacharyya, Jagannath; Pradhan, Subrata; Sikdar, Narattam; Das, Srirupa; Chakraborty, Saikat; Kumar, Sachin; Lakhanpaul, Suman; Sen, Soumitra K

2015-06-01

Over-expression of the unedited mitochondrial orfB gene product generates male sterility in fertile indica rice lines in a dose-dependent manner. Cytoplasmic male sterility (CMS) and nuclear-controlled fertility restoration are widespread developmental features in plant reproductive systems. In self-pollinated crop plants, these processes often provide useful tools to exploit hybrid vigour. The wild abortive CMS has been employed in the majority of the "three-line" hybrid rice production since 1970s. In the present study, we provide experimental evidence for a positive functional relationship between the 1.1-kb unedited orfB gene transcript, and its translated product in the mitochondria with male sterility. The generation of the 1.1-kb unedited orfB gene transcripts increased during flowering, resulting in low ATP synthase activity in sterile plants. Following insertion of the unedited orfB gene into the genome of male-fertile plants, the plants became male sterile in a dose-dependent manner with concomitant reduction of ATPase activity of F1F0-ATP synthase (complex V). Fertility of the transgenic lines and normal activity of ATP synthase were restored by down-regulation of the unedited orfB gene expression through RNAi-mediated silencing. The genetic elements deciphered in this study could further be tested for their use in hybrid rice development.

Fisetin up-regulates the expression of adiponectin in 3T3-L1 adipocytes via the activation of silent mating type information regulation 2 homologue 1 (SIRT1)-deacetylase and peroxisome proliferator-activated receptors (PPARs).

PubMed

Jin, Taewon; Kim, Oh Yoen; Shin, Min-Jeong; Choi, Eun Young; Lee, Sung Sook; Han, Ye Sun; Chung, Ji Hyung

2014-10-29

Adiponectin, an adipokine, has been described as showing physiological benefits against obesity-related malfunctions and vascular dysfunction. Several natural compounds that promote the expression and secretion of adipokines in adipocytes could be useful for treating metabolic disorders. This study investigated the effect of fisetin, a dietary flavonoid, on the regulation of adiponectin in adipocytes using 3T3-L1 preadipocytes. The expression and secretion of adiponectin increased in 3T3-L1 cells upon treatment with fisetin in a dose-dependent manner. Fisetin-induced adiponectin secretion was inhibited by peroxisome proliferator-activated receptor (PPAR) antagonists. It was also revealed that fisetin increased the activities of PPARs and silent mating type information regulation 2 homologue 1 (SIRT1) in a dose-dependent manner. Furthermore, the up-regulation of adiponectin and the activation of PPARs induced by fisetin were prevented by a SIRT1 inhibitor. Fisetin also promoted deacetylation of PPAR γ coactivator 1 (PGC-1) and its interaction with PPARs. SIRT knockdown by siRNA significantly decreased both adiponectin production and PPARs-PGC-1 interaction. These results provide evidence that fisetin promotes the gene expression of adiponectin through the activation of SIRT1 and PPARs in adipocytes.

Catechol, a major component of smoke, influences primary root growth and root hair elongation through reactive oxygen species-mediated redox signaling.

PubMed

Wang, Ming; Schoettner, Matthias; Xu, Shuqing; Paetz, Christian; Wilde, Julia; Baldwin, Ian T; Groten, Karin

2017-03-01

Nicotiana attenuata germinates from long-lived seedbanks in native soils after fires. Although smoke signals have been known to break seed dormancy, whether they also affect seedling establishment and root development remains unclear. In order to test this, seedlings were treated with smoke solutions. Seedlings responded in a dose-dependent manner with significantly increased primary root lengths, due mainly to longitudinal cell elongation, increased numbers of lateral roots and impaired root hair development. Bioassay-driven fractionations and NMR were used to identify catechol as the main active compound for the smoke-induced root phenotype. The transcriptome analysis revealed that mainly genes related to auxin biosynthesis and redox homeostasis were altered after catechol treatment. However, histochemical analyses of reactive oxygen species (ROS) and the inability of auxin applications to rescue the phenotype clearly indicated that highly localized changes in the root's redox-status, rather than in levels of auxin, are the primary effector. Moreover, H 2 O 2 application rescued the phenotype in a dose-dependent manner. Chemical cues in smoke not only initiate seed germination, but also influence seedling root growth; understanding how these cues work provides new insights into the molecular mechanisms by which plants adapt to post-fire environments. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Anti-Alzheimer activity of isolated karanjin from Pongamia pinnata (L.) pierre and embelin from Embelia ribes Burm.f.

PubMed

Saini, Prachi; Lakshmayya, L; Bisht, Vinod Singh

2017-01-01

The aim of this study is to find out the anti-Alzheimer's activity of isolated karanjin and embelin. Karanjin isolated from Pongamia pinnata (L.) pierre and embelin from Embelia ribes Burm.f. and their purity was confirmed by ultraviolet spectrophotometric and Thin layer chromatography based study. Anti-Alzheimer's activity of isolated compounds were evaluated through elevated plus maze and Morris water maze model on Swiss albino mice. Diazepam (1 mg/kg body weight, intraperitoneally) was used for the induction of Alzheimer's like effects (amnesia) on Swiss albino mice and piracetam (200 mg/kg body weight, oral) used as a standard treatment. In EPM, embelin and karanjin decrease the transfer latency time in dose dependent manner and escape latency time in MWM method. A significant ( P < 0.01) reduction in amnesia with an anti-Alzheimer's effect found when results of isolated compounds were compared with standard and vehicle control. Diazepam (1 mg/kg) treated group showed significant increase in escape latency and transfer latency when compared with vehicle control; which indicates impairment in learning and memory. Both isolated compounds and standard significantly reversed the amnesia induced by diazepam and improved learning and memory of mice in dose and time dependent manner. This study supports the ethnobotanical use of these two plants in India for the management of nerve or brain related problems.

Effect of azelastine on sulphur dioxide induced impairment of ciliary motility in airway epithelium.

PubMed Central

Tamaoki, J; Chiyotani, A; Sakai, N; Takeyama, K; Konno, K

1993-01-01

OBJECTIVE--The effect of azelastine on airway mucociliary transport function was studied by measuring ciliary motility of human bronchial epithelium in vitro with a photoelectric method. METHOD--Bronchial epithelial cells were obtained by fibreoptic bronchoscopy, mounted in a Rose chamber, and perfused with Krebs-Henseleit solution. The preparations were placed on a microscope stage equipped with an illuminator, and the variations of light intensity caused by ciliary beating were detected by a photometer. RESULTS--The addition of azelastine to the perfusate increased ciliary beat frequency (CBF) in a dose dependent manner without ciliary discoordination. The mean (SE) maximal increase from the baseline value and the concentration required to produce a half maximal effect were 27.0 (4.2)% and 9.2 x 10(-6) mol/l, respectively. Exposure of the cells to the perfusate containing 3 ppm sulphur dioxide rapidly decreased CBF by 59.2 (5.0)%, and was accompanied by a reduction in intracellular cyclic AMP levels from 38.1 (4.3) to 10.1 (2.4) pmol/mg protein. This effect was prevented by pretreatment of cells with azelastine in a dose dependent manner. CONCLUSIONS--Azelastine not only stimulates ciliary motility of airway epithelium and hence mucociliary transport function, but may also protect against sulphur dioxide induced ciliary dysfunction, probably by inhibiting intracellular cyclic AMP loss. PMID:8322244

Anti-cancer activity of trans-chalcone in osteosarcoma: Involvement of Sp1 and p53.

PubMed

Silva, Gabriel; Marins, Mozart; Fachin, Ana Lúcia; Lee, Seong-Ho; Baek, Seung Joon

2016-10-01

Osteosarcoma is the most common bone cancer. Although the emergence of multidrug therapies has improved available treatments for osteosarcoma, approximately 30% of patients will still develop metastasis. Currently, much anticancer therapy uses drugs that affect oncogenes/tumor suppressor genes, such as p53 (up-regulation) and Sp1 (down-regulation). Chalcones are secondary metabolites of plants and have been demonstrated to induce apoptosis in human cancer cells. Building on this knowledge, we evaluated the ability of trans-chalcone to reduce viability, to induce apoptosis, and to alter gene expression of p53 and Sp1 in human osteosarcoma cell lines. We found that treatment of trans-chalcone inhibited growth of osteosarcoma cells in a dose- and time-dependent manner, with significant inhibition at 10 μM after 48 h; apoptosis was also induced in a dose-dependent manner, with 1.9- and 3.6-fold induction at 10 μM and 50 μM, respectively, compared to non-treated cells. Further experiments suggest that trans-chalcone affected Sp1 down-regulation at the transcriptional level, whereas trans-chalcone up-regulated p53 expression at the post-translational level. trans-chalcone and its derivatives could be important in the development of future clinical trials in osteosarcoma. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Protective effect of tea polyphenols against paracetamol-induced hepatotoxicity in mice is significantly correlated with cytochrome P450 suppression.

PubMed

Chen, Xia; Sun, Chang-Kai; Han, Guo-Zhu; Peng, Jin-Yong; Li, Ying; Liu, Yan-Xia; Lv, Yuan-Yuan; Liu, Ke-Xin; Zhou, Qin; Sun, Hui-Jun

2009-04-21

To investigate the hepatoprotective activity of tea polyphenols (TP) and its relation with cytochrome P450 (CYP450) expression in mice. Hepatic CYP450 and CYPb(5) levels were measured by UV-spectrophotometry in mice 2 d after intraperitoneal TP (25, 50 and 100 mg/kg per day). Then the mice were intragastricly pre-treated with TP (100, 200 and 400 mg/kg per day) for six days before paracetamol (1000 mg/kg) was given. Their acute mortality was compared with that of control mice. The mice were pre-treated with TP (100, 200, and 400 mg/kg per day) for five days before paracetamol (500 mg/kg) was given. Hepatic CYP2E1 and CYP1A2 protein and mRNA expression levels were evaluated by Western blotting, immunohistochemical staining and transcriptase-polymerase chain reaction. The hepatic CYP450 and CYPb(5) levels in mice of TP-treated groups (100, 200 and 400 mg/kg per day) were decreased in a dose-dependent manner compared with those in the negative control mice. TP significantly attenuated the paracetamol-induced hepatic injury and dramatically reduced the mortality of paracetamol-treated mice. Furthermore, TP reduced CYP2E1 and CYP1A2 expression at both protein and mRNA levels in a dose-dependent manner. TP possess potential hepatoprotective properties and can suppress CYP450 expression.

Mitomycin C induces apoptosis in human epidural scar fibroblasts after surgical decompression for spinal cord injury.

PubMed

Sui, Tao; Ge, Da-Wei; Yang, Lei; Tang, Jian; Cao, Xiao-Jian; Ge, Ying-Bin

2017-04-01

Numerous studies have shown that topical application of mitomycin C after surgical decompression effectively reduces scar adhesion. However, the underlying mechanisms remain unclear. In this study, we investigated the effect of mitomycin C on the proliferation and apoptosis of human epidural scar fibroblasts. Human epidural scar fibroblasts were treated with various concentrations of mitomycin C (1, 5, 10, 20, 40 μg/mL) for 12, 24 and 48 hours. Mitomycin C suppressed the growth of these cells in a dose- and time-dependent manner. Mitomycin C upregulated the expression levels of Fas, DR4, DR5, cleaved caspase-8/9, Bax, Bim and cleaved caspase-3 proteins, and it downregulated Bcl-2 and Bcl-xL expression. In addition, inhibitors of caspase-8 and caspase-9 (Z-IETD-FMK and Z-LEHD-FMK, respectively) did not fully inhibit mitomycin C-induced apoptosis. Furthermore, mitomycin C induced endoplasmic reticulum stress by increasing the expression of glucose-regulated protein 78, CAAT/enhancer-binding protein homologous protein (CHOP) and caspase-4 in a dose-dependent manner. Salubrinal significantly inhibited the mitomycin C-induced cell viability loss and apoptosis, and these effects were accompanied by a reduction in CHOP expression. Our results support the hypothesis that mitomycin C induces human epidural scar fibroblast apoptosis, at least in part, via the endoplasmic reticulum stress pathway.

Amitriptyline Activates TrkA to Aid Neuronal Growth and Attenuate Anesthesia-Induced Neurodegeneration in Rat Dorsal Root Ganglion Neurons.

PubMed

Zheng, Xiaochun; Chen, Feng; Zheng, Ting; Huang, Fengyi; Chen, Jianghu; Tu, Wenshao

2016-05-01

Tricyclic antidepressant amitriptyline (AM) has been shown to exert neurotrophic activity on neurons. We thus explored whether AM may aid the neuronal development and protect anesthesia-induced neuro-injury in young spinal cord dorsal root ganglion (DRG) neurons.The DRG explants were prepared from 1-day-old rats. The effect of AM on aiding DRG neural development was examined by immunohistochemistry at dose-dependent manner. AM-induced changes in gene and protein expressions, and also phosphorylation states of tyrosine kinases receptor A (TrkA) and B (TrkB) in DRG, were examined by quantitative real-time polymerase chain reaction and western blot. The effect of AM on attenuating lidocaine-induced DRG neurodegeneration was examined by immunohistochemistry, and small interfering RNA (siRNA)-mediated TrkA/B down-regulation.Amitriptyline stimulated DRG neuronal development in dose-dependent manner, but exerted toxic effect at concentrations higher than 10 M. AM activated TrkA in DRG through phosphorylation, whereas it had little effect on TrkB-signaling pathway. AM reduced lidocaine-induced DRG neurodegeneration by regenerating neurites and growth cones. Moreover, the neuroprotection of AM on lidocaine-injured neurodegeneration was blocked by siRNA-mediated TrkA down-regulation, but not by TrkB down-regulation.Amitriptyline facilitated neuronal development and had protective effect on lidocaine-induced neurodegeneration, very likely through the activation of TrkA-signaling pathway in DRG.