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Sample records for cell oxidative stress

  1. Oxidative stress tolerance of early stage diabetic endothelial progenitor cell

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    Dewi Sukmawati

    2015-06-01

    Conclusions: Primitive BM-EPCs showed vasculogenic dysfunction in early diabetes. However the oxidative stress is not denoted as the major initiating factor of its cause. Our results suggest that primitive BM-KSL cell has the ability to compensate oxidative stress levels in early diabetes by increasing the expression of anti-oxidative enzymes.

  2. Effects of Oxidative Stress on Mesenchymal Stem Cell Biology

    Science.gov (United States)

    2016-01-01

    Mesenchymal stromal/stem cells (MSCs) are multipotent stem cells present in most fetal and adult tissues. Ex vivo culture-expanded MSCs are being investigated for tissue repair and immune modulation, but their full clinical potential is far from realization. Here we review the role of oxidative stress in MSC biology, as their longevity and functions are affected by oxidative stress. In general, increased reactive oxygen species (ROS) inhibit MSC proliferation, increase senescence, enhance adipogenic but reduce osteogenic differentiation, and inhibit MSC immunomodulation. Furthermore, aging, senescence, and oxidative stress reduce their ex vivo expansion, which is critical for their clinical applications. Modulation of sirtuin expression and activity may represent a method to reduce oxidative stress in MSCs. These findings have important implications in the clinical utility of MSCs for degenerative and immunological based conditions. Further study of oxidative stress in MSCs is imperative in order to enhance MSC ex vivo expansion and in vivo engraftment, function, and longevity. PMID:27413419

  3. Oxidative stress induces senescence in human mesenchymal stem cells

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    Brandl, Anita [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Meyer, Matthias; Bechmann, Volker [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Nerlich, Michael [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Angele, Peter, E-mail: Peter.Angele@klinik.uni-regensburg.de [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany)

    2011-07-01

    Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated {beta}-galactosidase positivity. Prolonged low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.

  4. N-acetylcysteine reduces oxidative stress in sickle cell patients

    NARCIS (Netherlands)

    Nur, Erfan; Brandjes, Dees P.; Teerlink, Tom; Otten, Hans-Martin; Elferink, Ronald P. J. Oude; Muskiet, Frits; Evers, Ludo M.; ten Cate, Hugo; Biemond, Bart J.; Duits, Ashley J.; Schnog, John-John B.

    2012-01-01

    Oxidative stress is of importance in the pathophysiology of sickle cell disease (SCD). In this open label randomized pilot study the effects of oral N-acetylcysteine (NAC) on phosphatidylserine (PS) expression as marker of cellular oxidative damage (primary end point), and markers of hemolysis, coag

  5. Oxidative stress induces mitochondrial fragmentation in frataxin-deficient cells

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    Lefevre, Sophie [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); ED515 UPMC, 4 place Jussieu 75005 Paris (France); Sliwa, Dominika [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); Rustin, Pierre [Inserm, U676, Physiopathology and Therapy of Mitochondrial Disease Laboratory, 75019 Paris (France); Universite Paris-Diderot, Faculte de Medecine Denis Diderot, IFR02 Paris (France); Camadro, Jean-Michel [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); Santos, Renata, E-mail: santos.renata@ijm.univ-paris-diderot.fr [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer Yeast frataxin-deficiency leads to increased proportion of fragmented mitochondria. Black-Right-Pointing-Pointer Oxidative stress induces complete mitochondrial fragmentation in {Delta}yfh1 cells. Black-Right-Pointing-Pointer Oxidative stress increases mitochondrial fragmentation in patient fibroblasts. Black-Right-Pointing-Pointer Inhibition of mitochondrial fission in {Delta}yfh1 induces oxidative stress resistance. -- Abstract: Friedreich ataxia (FA) is the most common recessive neurodegenerative disease. It is caused by deficiency in mitochondrial frataxin, which participates in iron-sulfur cluster assembly. Yeast cells lacking frataxin ({Delta}yfh1 mutant) showed an increased proportion of fragmented mitochondria compared to wild-type. In addition, oxidative stress induced complete fragmentation of mitochondria in {Delta}yfh1 cells. Genetically controlled inhibition of mitochondrial fission in these cells led to increased resistance to oxidative stress. Here we present evidence that in yeast frataxin-deficiency interferes with mitochondrial dynamics, which might therefore be relevant for the pathophysiology of FA.

  6. Cocoa phenolic extract protects pancreatic beta cells against oxidative stress.

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    Martín, María Angeles; Ramos, Sonia; Cordero-Herrero, Isabel; Bravo, Laura; Goya, Luis

    2013-07-31

    Diabetes mellitus is associated with reductions in glutathione, supporting the critical role of oxidative stress in its pathogenesis. Antioxidant food components such as flavonoids have a protective role against oxidative stress-induced degenerative and age-related diseases. Flavonoids constitute an important part of the human diet; they can be found in most plant foods, including green tea, grapes or cocoa and possess multiple biological activities. This study investigates the chemo-protective effect of a cocoa phenolic extract (CPE) containing mainly flavonoids against oxidative stress induced by tert-butylhydroperoxide (t-BOOH) on Ins-1E pancreatic beta cells. Cell viability and oxidative status were evaluated. Ins-1E cells treatment with 5-20 μg/mL CPE for 20 h evoked no cell damage and did not alter ROS production. Addition of 50 μM t-BOOH for 2 h increased ROS and carbonyl groups content and decreased reduced glutathione level. Pre-treatment of cells with CPE significantly prevented the t-BOOH-induced ROS and carbonyl groups and returned antioxidant defences to adequate levels. Thus, Ins-1E cells treated with CPE showed a remarkable recovery of cell viability damaged by t-BOOH, indicating that integrity of surviving machineries in the CPE-treated cells was notably protected against the oxidative insult.

  7. Cocoa Phenolic Extract Protects Pancreatic Beta Cells against Oxidative Stress

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    Laura Bravo

    2013-07-01

    Full Text Available Diabetes mellitus is associated with reductions in glutathione, supporting the critical role of oxidative stress in its pathogenesis. Antioxidant food components such as flavonoids have a protective role against oxidative stress-induced degenerative and age-related diseases. Flavonoids constitute an important part of the human diet; they can be found in most plant foods, including green tea, grapes or cocoa and possess multiple biological activities. This study investigates the chemo-protective effect of a cocoa phenolic extract (CPE containing mainly flavonoids against oxidative stress induced by tert-butylhydroperoxide (t-BOOH on Ins-1E pancreatic beta cells. Cell viability and oxidative status were evaluated. Ins-1E cells treatment with 5–20 μg/mL CPE for 20 h evoked no cell damage and did not alter ROS production. Addition of 50 μM t-BOOH for 2 h increased ROS and carbonyl groups content and decreased reduced glutathione level. Pre-treatment of cells with CPE significantly prevented the t-BOOH-induced ROS and carbonyl groups and returned antioxidant defences to adequate levels. Thus, Ins-1E cells treated with CPE showed a remarkable recovery of cell viability damaged by t-BOOH, indicating that integrity of surviving machineries in the CPE-treated cells was notably protected against the oxidative insult.

  8. Bridges between mitochondrial oxidative stress, ER stress and mTOR signaling in pancreatic β cells.

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    Wang, Jing; Yang, Xin; Zhang, Jingjing

    2016-08-01

    Pancreatic β cell dysfunction, i.e., failure to provide insulin in concentrations sufficient to control blood sugar, is central to the etiology of all types of diabetes. Current evidence implicates mitochondrial oxidative stress and endoplasmic reticulum (ER) stress in pancreatic β cell loss and impaired insulin secretion. Oxidative and ER stress are interconnected so that misfolded proteins induce reactive oxygen species (ROS) production; likewise, oxidative stress disturbs the ER redox state thereby disrupting correct disulfide bond formation and proper protein folding. mTOR signaling regulates many metabolic processes including protein synthesis, cell growth, survival and proliferation. Oxidative stress inhibits mTORC1, which is considered an important suppressor of mitochondrial oxidative stress in β cells, and ultimately, controls cell survival. The interplay between ER stress and mTORC1 is complicated, since the unfolded protein response (UPR) activation can occur upstream or downstream of mTORC1. Persistent activation of mTORC1 initiates protein synthesis and UPR activation, while in the later phase induces ER stress. Chronic activation of ER stress inhibits Akt/mTORC1 pathway, while under particular settings, acute activation of UPR activates Akt-mTOR signaling. Thus, modulating mitochondrial oxidative stress and ER stress via mTOR signaling may be an approach that will effectively suppress obesity- or glucolipotoxicity-induced metabolic disorders such as insulin resistance and type 2 diabetes mellitus (T2DM). In this review, we focus on the regulations between mTOR signaling and mitochondrial oxidative or ER stress in pancreatic β cells.

  9. Nuclear lamins and oxidative stress in cell proliferation and longevity.

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    Shimi, Takeshi; Goldman, Robert D

    2014-01-01

    In mammalian cells, the nuclear lamina is composed of a complex fibrillar network associated with the inner membrane of the nuclear envelope. The lamina provides mechanical support for the nucleus and functions as the major determinant of its size and shape. At its innermost aspect it associates with peripheral components of chromatin and thereby contributes to the organization of interphase chromosomes. The A- and B-type lamins are the major structural components of the lamina, and numerous mutations in the A-type lamin gene have been shown to cause many types of human diseases collectively known as the laminopathies. These mutations have also been shown to cause a disruption in the normal interactions between the A and B lamin networks. The impact of these mutations on nuclear functions is related to the roles of lamins in regulating various essential processes including DNA synthesis and damage repair, transcription and the regulation of genes involved in the response to oxidative stress. The major cause of oxidative stress is the production of reactive oxygen species (ROS), which is critically important for cell proliferation and longevity. Moderate increases in ROS act to initiate signaling pathways involved in cell proliferation and differentiation, whereas excessive increases in ROS cause oxidative stress, which in turn induces cell death and/or senescence. In this review, we cover current findings about the role of lamins in regulating cell proliferation and longevity through oxidative stress responses and ROS signaling pathways. We also speculate on the involvement of lamins in tumor cell proliferation through the control of ROS metabolism.

  10. Erythrocyte oxidative stress markers in children with sickle cell disease

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    Priscila Bacarin Hermann

    2016-08-01

    Full Text Available Abstract Objective To determine eight parameters of oxidative stress markers in erythrocytes from children with sickle cell disease and compare with the same parameters in erythrocytes from healthy children, since oxidative stress plays an important role in the pathophysiology of sickle cell disease and because this disease is a serious public health problem in many countries. Methods Blood samples were obtained from 45 children with sickle cell disease (21 males and 24 females with a mean age of 9 years; range: 3–13 years and 280 blood samples were obtained from children without hemoglobinopathies (137 males and 143 females with a mean age of 10 years; range: 8–11 years, as a control group. All blood samples were analyzed for methemoglobin, reduced glutathione, thiobarbituric acid reactive substances, percentage of hemolysis, reactive oxygen species, and activity of the enzymes glucose 6-phosphate dehydrogenase, superoxide dismutase, and catalase. Data were analyzed using Student's t-test and were expressed as the mean ± standard deviation. A p-value of <0.05 was considered significant. Results Significant differences were observed between children with sickle cell disease and the control group for the parameters methemoglobin, thiobarbituric acid reactive substances, hemolysis, glucose 6-phosphate dehydrogenase activity, and reactive oxygen species, with higher levels in the patients than in the controls. Conclusions Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients.

  11. Oxidative Stress-Induced Dysfunction of Muller Cells During Starvation

    DEFF Research Database (Denmark)

    Toft-Kehler, Anne Katrine; Gurubaran, Iswariyaraja Sridevi; Madsen, Claus Desler;

    2016-01-01

    PURPOSE. Muller cells support retinal neurons with essential functions. Here, we aim to examine the impact of starvation and oxidative stress on glutamate uptake and mitochondrial function in Muller cells. METHODS. Cultured human retinal Muller cells (MIO-M1) were exposed to H2O2 and additional...... starvation for 24 hours. Effects of starvation and H2O2 on glutamate uptake and mitochondrial function were assessed by kinetic glutamate uptake assays and Seahorse assays, respectively. Cell survival was evaluated by cell viability assays. mRNA and protein expressions were assessed by quantitative PCR...... and Western blot. RESULTS. Starvation of Muller cells increased the glutamate uptake capacity as well as the expression of the most abundant glutamate transporter, EAAT1. Mitochondrial and glycolytic activity were diminished in starved Muller cells despite unaffected cell viability. Simultaneous starvation...

  12. Cell differentiation versus cell death: extracellular glucose is a key determinant of cell fate following oxidative stress exposure

    OpenAIRE

    Poulsen, R C; Knowles, H.J.; Carr, A. J.; HULLEY, P. A.

    2014-01-01

    Cells, particularly mechano-sensitive musculoskeletal cells such as tenocytes, routinely encounter oxidative stress. Oxidative stress can not only stimulate tissue repair, but also cause damage leading to tissue degeneration. As diabetes is associated with increased oxidative damage as well as increased risk of tendon degeneration, the aim of this study was to determine if extracellular glucose levels alter the response of tendon cells to oxidative stress. Primary human tenocytes were culture...

  13. Uranium induces oxidative stress in lung epithelial cells

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    Periyakaruppan, Adaikkappan; Kumar, Felix; Sarkar, Shubhashish; Sharma, Chidananda S.; Ramesh, Govindarajan T. [Texas Southern University, Molecular Neurotoxicology Laboratory/Proteomics Core, Department of Biology, Houston, TX (United States)

    2007-06-15

    Uranium compounds are widely used in the nuclear fuel cycle, antitank weapons, tank armor, and also as a pigment to color ceramics and glass. Effective management of waste uranium compounds is necessary to prevent exposure to avoid adverse health effects on the population. Health risks associated with uranium exposure includes kidney disease and respiratory disorders. In addition, several published results have shown uranium or depleted uranium causes DNA damage, mutagenicity, cancer and neurological defects. In the current study, uranium toxicity was evaluated in rat lung epithelial cells. The study shows uranium induces significant oxidative stress in rat lung epithelial cells followed by concomitant decrease in the antioxidant potential of the cells. Treatment with uranium to rat lung epithelial cells also decreased cell proliferation after 72 h in culture. The decrease in cell proliferation was attributed to loss of total glutathione and superoxide dismutase in the presence of uranium. Thus the results indicate the ineffectiveness of antioxidant system's response to the oxidative stress induced by uranium in the cells. (orig.)

  14. N-acetylcysteine reduces oxidative stress in sickle cell patients.

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    Nur, Erfan; Brandjes, Dees P; Teerlink, Tom; Otten, Hans-Martin; Oude Elferink, Ronald P J; Muskiet, Frits; Evers, Ludo M; ten Cate, Hugo; Biemond, Bart J; Duits, Ashley J; Schnog, John-John B

    2012-07-01

    Oxidative stress is of importance in the pathophysiology of sickle cell disease (SCD). In this open label randomized pilot study the effects of oral N-acetylcysteine (NAC) on phosphatidylserine (PS) expression as marker of cellular oxidative damage (primary end point), and markers of hemolysis, coagulation and endothelial activation and NAC tolerability (secondary end points) were studied. Eleven consecutive patients (ten homozygous [HbSS] sickle cell patients, one HbSβ(0)-thalassemia patient) were randomly assigned to treatment with either 1,200 or 2,400 mg NAC daily during 6 weeks. The data indicate an increment in whole blood glutathione levels and a decrease in erythrocyte outer membrane phosphatidylserine exposure, plasma levels of advanced glycation end-products (AGEs) and cell-free hemoglobin after 6 weeks of NAC treatment in both dose groups. One patient did not tolerate the 2,400 mg dose and continued with the 1,200 mg dose. During the study period, none of the patients experienced painful crises or other significant SCD or NAC related complications. These data indicate that N-acetylcysteine treatment of sickle cell patients may reduce SCD related oxidative stress.

  15. Prune melanoidins protect against oxidative stress and endothelial cell death.

    Science.gov (United States)

    Posadino, Anna Maria; Cossu, Annalisa; Piga, Antonio; Madrau, Monica Assunta; Del Caro, Alessandra; Colombino, Maria; Paglietti, Bianca; Rubino, Salvatore; Iaccarino, Ciro; Crosio, Claudia; Sanna, Bastiano; Pintus, Gianfranco

    2011-06-01

    The health-promoting effects of fruit and vegetable consumption are thought to be due to phytochemicals contained in fresh plant material. Whether processed plant foods provide the same benefits as unprocessed ones is an open question. Melanoidins from heat-processed plums (prunes) were isolated and their presence confirmed by hydroxymethylfurfural content and browning index. Oxidative-induced endothelial cell (EC) damage is the trigger for the development of cardiovascular diseases (CVD); therefore the potential protective effect of prune melanoidins on hydrogen peroxide-induced oxidative cell damage was investigated on human endothelial ECV304 cells. Cytoplasmic and mitochondrial redox status was assessed by using the novel, redox-sensitive, ratiometric fluorescent protein sensor (roGFP), while mitochondrial membrane potential (MMP) was investigated with the fluorescent dye, JC-1. Treatment of ECV304 cells with hydrogen peroxide dose-dependently induced both mitochondrial and cytoplasmic oxidation, in addition to MMP dissipation, with ensuing cell death. Pretreatment of ECV304 with prune melanoidins, significantly counteracted and ultimately abolished hydrogen peroxide elicited phenomena, clearly indicating that these polymers protect human EC against oxidative stress.

  16. Induction of oxidative stress and oxidative damage in rat glial cells by acrylonitrile.

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    Kamendulis, L M; Jiang, J; Xu, Y; Klaunig, J E

    1999-08-01

    Chronic treatment of rats with acrylonitrile (ACN) resulted in a dose-related increase in glial cell tumors (astrocytomas). While the exact mechanism(s) for ACN-induced carcinogenicity remains unresolved, non-genotoxic and possibly tumor promotion modes of action appear to be involved in the induction of glial tumors. Recent studies have shown that ACN induced oxidative stress selectively in rat brain in a dose-responsive manner. The present study examined the ability of ACN to induce oxidative stress in a rat glial cell line, a target tissue, and in cultured rat hepatocytes, a non-target tissue of ACN carcinogenicity. Glial cells and hepatocytes were treated for 1, 4 and 24 h with sublethal concentrations of ACN. ACN induced an increase in oxidative DNA damage, as evidenced by increased production of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in glial cells but not in rat hepatocytes. Hydroxyl radical formation following ACN treatment was also selectively increased in glial cells. Following 1 and 4 h of ACN exposure, the levels of the non-enzymatic antioxidant glutathione, as well as the activities of the enzymatic antioxidants catalase and superoxide dismutase were significantly decreased in the rat glial cells. Lipid peroxidation and the activity of glutathione peroxidase were not affected by ACN treatment in rat glial cells. No changes in any of these biomarkers of oxidative stress were observed in hepatocytes treated with ACN. These data indicate that ACN selectively induced oxidative stress in rat glial cells.

  17. SIRT1 Activating Compounds Reduce Oxidative Stress and Prevent Cell Death in Neuronal Cells

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    Reas S Khan

    2012-12-01

    Full Text Available Activation of SIRT1, an NAD+-dependent deacetylase, prevents retinal ganglion cell (RGC loss in optic neuritis, an inflammatory demyelinating optic nerve disease. While SIRT1 deacetylates numerous protein targets, downstream mechanisms of SIRT1 activation mediating this neuroprotective effect are unknown. SIRT1 increases mitochondrial function and reduces oxidative stress in muscle and other cells, and oxidative stress occurs in neuronal degeneration. We examined whether SIRT1 activators reduce oxidative stress and promote mitochondrial function in neuronal cells. Oxidative stress, marked by reactive oxygen species (ROS accumulation, was induced in RGC-5 cells by serum deprivation, or addition of doxorubicin or hydrogen peroxide, and resulted in significant cell loss. SIRT1 activators resveratrol and SRTAW04 reduced ROS levels, and promoted cell survival in RGC-5 cells as well as primary RGC cultures. Effects were blocked by SIRT1 siRNA. SIRT1 activators also increased expression of succinate dehydrogenase, a mitochondrial enzyme, and promoted deacetylation of PGC-1α, a co-enzyme involved in mitochondrial function. Results show SIRT1 activators prevent cell loss by reducing oxidative stress and promoting mitochondrial function in a neuronal cell line. Results suggest SIRT1 activators can mediate neuroprotective effects during optic neuritis by these mechanisms, and they have the potential to preserve neurons in other neurodegenerative diseases that involve oxidative stress.

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

    Science.gov (United States)

    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.

  19. Induction of necrotic cell death by oxidative stress in retinal pigment epithelial cells.

    Science.gov (United States)

    Hanus, J; Zhang, H; Wang, Z; Liu, Q; Zhou, Q; Wang, S

    2013-12-12

    Age-related macular degeneration (AMD) is a degenerative disease of the retina and the leading cause of blindness in the elderly. Retinal pigment epithelial (RPE) cell death and the resultant photoreceptor apoptosis are characteristic of late-stage dry AMD, especially geographic atrophy (GA). Although oxidative stress and inflammation have been associated with GA, the nature and underlying mechanism for RPE cell death remains controversial, which hinders the development of targeted therapy for dry AMD. The purpose of this study is to systematically dissect the mechanism of RPE cell death induced by oxidative stress. Our results show that characteristic features of apoptosis, including DNA fragmentation, caspase 3 activation, chromatin condensation and apoptotic body formation, were not observed during RPE cell death induced by either hydrogen peroxide or tert-Butyl hydroperoxide. Instead, this kind of cell death can be prevented by RIP kinase inhibitors necrostatins but not caspase inhibitor z-VAD, suggesting necrotic feature of RPE cell death. Moreover, ATP depletion, receptor interacting protein kinase 3 (RIPK3) aggregation, nuclear and plasma membrane leakage and breakdown, which are the cardinal features of necrosis, were observed in RPE cells upon oxidative stress. Silencing of RIPK3, a key protein in necrosis, largely prevented oxidative stress-induced RPE death. The necrotic nature of RPE death is consistent with the release of nuclear protein high mobility group protein B1 into the cytoplasm and cell medium, which induces the expression of inflammatory gene TNFα in healthy RPE and THP-1 cells. Interestingly, features of pyroptosis or autophagy were not observed in oxidative stress-treated RPE cells. Our results unequivocally show that necrosis, but not apoptosis, is a major type of cell death in RPE cells in response to oxidative stress. This suggests that preventing oxidative stress-induced necrotic RPE death may be a viable approach for late-stage dry

  20. High glucose-mediated oxidative stress impairs cell migration.

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    Marcelo L Lamers

    Full Text Available Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we evaluate the hypothesis that high glucose concentrations inhibit cell migration. Using CHO.K1 cells, NIH-3T3 fibroblasts, mouse embryonic fibroblasts and primary skin fibroblasts from control and diabetic rats cultured in 5 mM D-glucose (low glucose, LG, 25 mM D-glucose (high glucose, HG or 25 mM L-glucose medium (osmotic control--OC, we analyzed the migration speed, protrusion stability, cell polarity, adhesion maturation and the activity of the small Rho GTPase Rac1. We also analyzed the effects of reactive oxygen species by incubating cells with the antioxidant N-Acetyl-Cysteine (NAC. We observed that HG conditions inhibited cell migration when compared to LG or OC. This inhibition resulted from impaired cell polarity, protrusion destabilization and inhibition of adhesion maturation. Conversely, Rac1 activity, which promotes protrusion and blocks adhesion maturation, was increased in HG conditions, thus providing a mechanistic basis for the HG phenotype. Most of the HG effects were partially or completely rescued by treatment with NAC. These findings demonstrate that HG impairs cell migration due to an increase in oxidative stress that causes polarity loss, deficient adhesion and protrusion. These alterations arise, in large part, from increased Rac1 activity and may contribute to the poor wound healing observed in diabetic patients.

  1. Acrolein induction of oxidative stress and degranulation in mast cells.

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    Hochman, Daniel J; Collaco, Christopher R; Brooks, Edward G

    2014-08-01

    Increases in asthma worldwide have been associated epidemiologically with expanding urban air pollution. The mechanistic relationship between airway hyper-responsiveness, inflammation, and ambient airborne triggers remains ambiguous. Acrolein, a ubiquitous aldehyde pollutant, is a product of incomplete combustion reactions. Acrolein is abundant in cigarette smoke, effluent from industrial smokestacks, diesel exhaust, and even hot oil cooking vapors. Acrolein is a potent airway irritant and can induce airway hyper-responsiveness and inflammation in the lungs of animal models. In the present study, we utilized the mast cell analog, RBL-2H3, to interrogate the responses of cells relevant to airway inflammation and allergic responses as a model for the induction of asthma-like conditions upon exposure to acrolein. We hypothesized that acrolein would induce oxidative stress and degranulation in airway mast cells. Our results indicate that acrolein at 1 ppm initiated degranulation and promoted the generation of reactive oxygen species (ROS). Introduction of antioxidants to the system significantly reduced both ROS generation and degranulation. At higher levels of exposure (above 100 ppm), RBL-2H3 cells displayed signs of severe toxicity. This experimental data indicates acrolein can induce an allergic inflammation in mast cell lines, and the initiation of degranulation was moderated by the application of antioxidants.

  2. Nivalenol induces oxidative stress and increases deoxynivalenol pro-oxidant effect in intestinal epithelial cells

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    Del Regno, Marisanta; Adesso, Simona; Popolo, Ada [Department of Pharmacy, School of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132–84084 Fisciano, Salerno (Italy); Quaroni, Andrea [Department of Biomedical Sciences, Cornell University, Veterinary Research Tower, Cornell University, Ithaca, NY 14853–6401 (United States); Autore, Giuseppina [Department of Pharmacy, School of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132–84084 Fisciano, Salerno (Italy); Severino, Lorella [Department of Pathology and Animal Health, Division of Toxicology, School of Veterinary Medicine, University of Naples “Federico II”, Via Delpino 1, 80137 Naples (Italy); Marzocco, Stefania, E-mail: smarzocco@unisa.it [Department of Pharmacy, School of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132–84084 Fisciano, Salerno (Italy)

    2015-06-01

    Mycotoxins are secondary fungal metabolites often found as contaminants in almost all agricultural commodities worldwide, and the consumption of food or feed contaminated by mycotoxins represents a major risk for human and animal health. Reactive oxygen species are normal products of cellular metabolism. However, disproportionate generation of reactive oxygen species poses a serious problem to bodily homeostasis and causes oxidative tissue damage. In this study we analyzed the effect of two trichothecenes mycotoxins: nivalenol and deoxynivalenol, alone and in combination, on oxidative stress in the non-tumorigenic intestinal epithelial cell line IEC-6. Our results indicate the pro-oxidant nivalenol effect in IEC-6, the stronger pro-oxidant effect of nivalenol when compared to deoxynivalenol and, interestingly, that nivalenol increases deoxynivalenol pro-oxidative effects. Mechanistic studies indicate that the observed effects were mediated by NADPH oxidase, calcium homeostasis alteration, NF-kB and Nrf2 pathways activation and by iNOS and nitrotyrosine formation. The toxicological interaction by nivalenol and deoxynivalenol reported in this study in IEC-6, points out the importance of the toxic effect of these mycotoxins, mostly in combination, further highlighting the risk assessment process of these toxins that are of growing concern. - Highlights: • Nivalenol induces oxidative stress in intestinal epithelial cells (IECs). • Nivalenol increases deoxynivalenol pro-oxidant effects in IECs. • Nivalenol and deoxynivalenol trigger antioxidant response IECs. • These results indicate the importance of mycotoxins co-contamination.

  3. Oxidized low density lipoprotein increases RANKL level in human vascular cells. Involvement of oxidative stress

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    Mazière, Cécile, E-mail: maziere.cecile@chu-amiens.fr [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France); Salle, Valéry [Internal Medicine, North Hospital University, Place Victor Pauchet, Amiens 80000 (France); INSERM U1088 (EA 4292), SFR CAP-Santé (FED 4231), University of Picardie – Jules Verne (France); Gomila, Cathy; Mazière, Jean-Claude [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France)

    2013-10-18

    Highlights: •Oxidized LDL enhances RANKL level in human smooth muscle cells. •The effect of OxLDL is mediated by the transcription factor NFAT. •UVA, H{sub 2}O{sub 2} and buthionine sulfoximine also increase RANKL level. •All these effects are observed in human fibroblasts and endothelial cells. -- Abstract: Receptor Activator of NFκB Ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) have been shown to play a role not only in bone remodeling but also in inflammation, arterial calcification and atherosclerotic plaque rupture. In human smooth muscle cells, Cu{sup 2+}-oxidized LDL (CuLDL) 10–50 μg/ml increased reactive oxygen species (ROS) and RANKL level in a dose-dependent manner, whereas OPG level was not affected. The lipid extract of CuLDL reproduced the effects of the whole particle. Vivit, an inhibitor of the transcription factor NFAT, reduced the CuLDL-induced increase in RANKL, whereas PKA and NFκB inhibitors were ineffective. LDL oxidized by myeloperoxidase (MPO-LDL), or other pro-oxidant conditions such as ultraviolet A (UVA) irradiation, incubation with H{sub 2}O{sub 2} or with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis{sub ,} also induced an oxidative stress and enhanced RANKL level. The increase in RANKL in pro-oxidant conditions was also observed in fibroblasts and endothelial cells. Since RANKL is involved in myocardial inflammation, vascular calcification and plaque rupture, this study highlights a new mechanism whereby OxLDL might, by generation of an oxidative stress, exert a deleterious effect on different cell types of the arterial wall.

  4. Role of Exercise-Induced Oxidative Stress in Sickle Cell Trait and Disease.

    Science.gov (United States)

    Chirico, Erica N; Faës, Camille; Connes, Philippe; Canet-Soulas, Emmanuelle; Martin, Cyril; Pialoux, Vincent

    2016-05-01

    Sickle cell disease is a class of hemoglobinopathy in humans, which is the most common inherited disease in the world. Although complications of sickle cell disease start from polymerization of red blood cells during its deoxygenating phase, the oxidative stress resulting from the biological processes associated with this disease (ischaemic and hypoxic injuries, hemolysis and inflammation) has been shown to contribute to its pathophysiology. It is widely known that chronic exercise reduces oxidative stress in healthy people, mainly via improvement of antioxidant enzyme efficiency. In addition, recent studies in other diseases, as well as in sickle cell trait carriers and in a mouse model of sickle cell disease, have shown that regular physical activity could decrease oxidative stress. The purpose of this review is to summarize the role of oxidative stress in sickle cell disease and the effects of acute and chronic exercise on the pro-oxidant/antioxidant balance in sickle cell trait and sickle cell disease.

  5. Oxidative stress in NSC-741909-induced apoptosis of cancer cells

    Directory of Open Access Journals (Sweden)

    Huang Peng

    2010-04-01

    Full Text Available Abstract Background NSC-741909 is a novel anticancer agent that can effectively suppress the growth of several cell lines derived from lung, colon, breast, ovarian, and kidney cancers. We recently showed that NSC-741909-induced antitumor activity is associated with sustained Jun N-terminal kinase (JNK activation, resulting from suppression of JNK dephosphorylation associated with decreased protein levels of MAPK phosphatase-1. However, the mechanisms of NSC-741909-induced antitumor activity remain unclear. Because JNK is frequently activated by oxidative stress in cells, we hypothesized that reactive oxygen species (ROS may be involved in the suppression of JNK dephosphorylation and the cytotoxicity of NSC-741909. Methods The generation of ROS was measured by using the cell-permeable nonfluorescent compound H2DCF-DA and flow cytometry analysis. Cell viability was determined by sulforhodamine B assay. Western blot analysis, immunofluorescent staining and flow cytometry assays were used to determine apoptosis and molecular changes induced by NSC-741909. Results Treatment with NSC-741909 induced robust ROS generation and marked MAPK phosphatase-1 and -7 clustering in NSC-741909-sensitive, but not resistant cell lines, in a dose- and time-dependent manner. The generation of ROS was detectable as early as 30 min and ROS levels were as high as 6- to 8-fold above basal levels after treatment. Moreover, the NSC-741909-induced ROS generation could be blocked by pretreatment with antioxidants, such as nordihydroguaiaretic acid, aesculetin, baicalein, and caffeic acid, which in turn, inhibited the NSC-741909-induced JNK activation and apoptosis. Conclusion Our results demonstrate that the increased ROS production was associated with NSC-741909-induced antitumor activity and that ROS generation and subsequent JNK activation is one of the primary mechanisms of NSC-741909-mediated antitumor cell activity.

  6. Furan fatty acids efficiently rescue brain cells from cell death induced by oxidative stress

    NARCIS (Netherlands)

    Teixeira, A.; Cox, R.C.; Egmond, M.R.

    2013-01-01

    Treatment of rat brain C6 astroglioma cells with furan fatty acid F6 prior to exposure to hydrogen peroxide shows a strong protective effect of F6 against cell death resulting from oxidative stress. This protective effect is obtained only for F6 administered as a free fatty acid and with an intact f

  7. Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and Androgen Receptor Antagonism

    Science.gov (United States)

    2015-08-01

    AD_________________ Award Number: W81XWH-12-1-0340 TITLE: Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and Androgen...COVERED 1 Aug 2014 - 21 Jul 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and

  8. Furan fatty acids efficiently rescue brain cells from cell death induced by oxidative stress.

    Science.gov (United States)

    Teixeira, Antoinette; Cox, Ruud C; Egmond, Maarten R

    2013-08-01

    Treatment of rat brain C6 astroglioma cells with furan fatty acid F6 prior to exposure to hydrogen peroxide shows a strong protective effect of F6 against cell death resulting from oxidative stress. This protective effect is obtained only for F6 administered as a free fatty acid and with an intact furan ring. It is proposed that brain cells are rescued by F6 scavenging radicals elicited by lipid peroxidation within the cell membrane. Oxidative processes outside the cell membrane, such as protein carbonylation, are not affected by F6. Furan fatty acids such as those present in fish oils and marine organisms are likely beneficial for consumption in reducing the risk of diseases that have been implicated to arise from oxidative stress, such as Alzheimer's disease.

  9. Preconditioning L6 Muscle Cells with Naringin Ameliorates Oxidative Stress and Increases Glucose Uptake

    OpenAIRE

    R. Dhanya; K B Arun; Nisha, V. M.; H P Syama; Nisha, P.; T R Santhosh Kumar; Jayamurthy, P.

    2015-01-01

    Enhanced oxidative stress contributes to pathological changes in diabetes and its complications. Thus, strategies to reduce oxidative stress may alleviate these pathogenic processes. Herein, we have investigated Naringin mediated regulation of glutathione (GSH) & intracellular free radical levels and modulation of glucose uptake under oxidative stress in L6 cell lines. The results from the study demonstrated a marked decrease in glutathione with a subsequent increase in free radical levels, w...

  10. Oxidative stress

    Directory of Open Access Journals (Sweden)

    Stevanović Jelka

    2012-01-01

    Full Text Available The unceasing need for oxygen is in contradiction to the fact that it is in fact toxic to mammals. Namely, its monovalent reduction can have as a consequence the production of short-living, chemically very active free radicals and certain non-radical agents (nitrogen-oxide, superoxide-anion-radicals, hydroxyl radicals, peroxyl radicals, singlet oxygen, peroxynitrite, hydrogen peroxide, hypochlorous acid, and others. There is no doubt that they have numerous positive roles, but when their production is stepped up to such an extent that the organism cannot eliminate them with its antioxidants (superoxide-dismutase, glutathione-peroxidase, catalase, transferrin, ceruloplasmin, reduced glutathion, and others, a series of disorders is developed that are jointly called „oxidative stress.“ The reactive oxygen species which characterize oxidative stress are capable of attacking all main classes of biological macromolecules, actually proteins, DNA and RNA molecules, and in particular lipids. The free radicals influence lipid peroxidation in cellular membranes, oxidative damage to DNA and RNA molecules, the development of genetic mutations, fragmentation, and the altered function of various protein molecules. All of this results in the following consequences: disrupted permeability of cellular membranes, disrupted cellular signalization and ion homeostasis, reduced or loss of function of damaged proteins, and similar. That is why the free radicals that are released during oxidative stress are considered pathogenic agents of numerous diseases and ageing. The type of damage that will occur, and when it will take place, depends on the nature of the free radicals, their site of action and their source. [Projekat Ministarstva nauke Republike Srbije, br. 173034, br. 175061 i br. 31085

  11. Protection by 6-aminonicotinamide against oxidative stress in cardiac cells

    DEFF Research Database (Denmark)

    Hofgaard, Johannes P; Sigurdardottir, Kristin Sigridur; Treiman, Marek

    2006-01-01

    Oxidative stress at the time of reperfusion is a major aspect of ischemia-reperfusion injury in heart as well as in other organs. There is a continuing interest in development of pharmacological approaches to alleviate this injury. 6-Aminonicotinamide (6AN) has been shown to diminish myocardial n...

  12. Mangiferin induces cell death against rhabdomyosarcoma through sustained oxidative stress

    OpenAIRE

    Vishwanadha Vijaya Padma; Palanisamy Kalaiselvi; Rangasamy Yuvaraj; M. Rabeeth

    2015-01-01

    Background: Embryonic rhabdomyosarcoma (RD) is the most prevalent type of cancer among children. The present study aimed to investigate cell death induced by mangiferin in RD cells. Methods: The Inhibitory concentration (IC50) value of mangiferin was determined by an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Cell death induced by mangiferin against RD cells was determined through lactate dehydrogenase and nitric oxide release, intracellular calcium levels, r...

  13. NRF2 Oxidative Stress Induced by Heavy Metals is Cell Type Dependent

    Science.gov (United States)

    Exposure to metallic environmental toxicants has been demonstrated to induce a variety of oxidative stress responses in mammalian cells. The transcription factor Nrf2 is activated in response to oxidative stress and coordinates the expression of antioxidant gene products. In this...

  14. Erythrocyte oxidative stress is associated with cell deformability in patients with retinal vein occlusion.

    Science.gov (United States)

    Becatti, M; Marcucci, R; Gori, A M; Mannini, L; Grifoni, E; Alessandrello Liotta, A; Sodi, A; Tartaro, R; Taddei, N; Rizzo, S; Prisco, D; Abbate, R; Fiorillo, C

    2016-11-01

    Essentials Retinal vein occlusion (RVO), characterized by blood hyperviscosity, has an unclear pathogenesis. We aimed to find out if hemorheological profile is altered by oxidative stress in RVO patients. Red blood cell (RBC) oxidative stress is associated to whole blood viscosity and RBC deformability. Reactive oxygen species alter RBC membrane rigidity, playing a key role in RVO pathogenesis.

  15. K562 cells display different vulnerability to H₂O₂ induced oxidative stress in differing cell cycle phases.

    Science.gov (United States)

    Akcakaya, Handan; Dal, Fulya; Tok, Sabiha; Cinar, Suzan-Adin; Nurten, Rustem

    2015-02-01

    Oxidative stress can be defined as the increase of oxidizing agents like reactive oxygen and nitrogen species, or the imbalance between the antioxidative defense mechanism and oxidants. Cell cycle checkpoint response can be defined as the arrest of the cell cycle functioning after damaging chemical exposure. This temporary arrest may be a period of time given to the cells to repair the DNA damage before entering the cycle again and completing mitosis. In order to determine the effects of oxidative stress on several cell cycle phases, human erytroleukemia cell line (K562) was synchronized with mimosine and genistein, and cell cycle analysis carried out. Synchronized cells were exposed to oxidative stress with hydrogen peroxide (H2O2) at several concentrations and different times. Changes on mitochondria membrane potential (ΔΨm) of K562 cells were analyzed in G1, S, and G2 /M using Rhodamine 123 (Rho 123). To determine apoptosis and necrosis, stressed cells were stained with Annexin V (AnnV) and propidium iodide (PI) for flow cytometry. Changes were observed in the ΔΨm of synchronized and asynchronized cells that were exposed to oxidative stress. Synchronized cells in S phase proved resistant to the effects of oxidative stress and synchronized cells at G2 /M phase were sensitive to the effects of H2O2 -induced oxidative stress at 500 μM and above.

  16. In vitro investigation of ultrasound-induced oxidative stress on human lens epithelial cells.

    Science.gov (United States)

    Rwei, Patrick; Alex Gong, Cihun-Siyong; Luo, Li-Jyuan; Lin, Meng-Bo; Lai, Jui-Yang; Liu, Hao-Li

    2017-01-22

    The effect of ultrasound exposure on human lens epithelial cells (HLE-B3) was investigated in vitro, specifically on the generation of oxidative stress upon ultrasound application using various clinically-relevant settings. In addition to ultrasound-induced heat effects, oxidative stress has been recently proposed as one of the main mechanisms for ultrasound-induced effects on human cells. In this work, the levels of biocompatibility and generation of oxidative stress by exposure of ultrasound to HLE-B3 were evaluated quantitatively and qualitatively by the MTT assay, Live/Dead assay, reactive oxygen species (ROS) and intracellular calcium level. Oxidative stress induction is traditionally achieved through administrations of H2O2 and thus the administration of H2O2 was used as the positive control group for comparison herein. Concerning the administrations of H2O2 are considered invasive and may potentially have side effects, ultrasound as physical stimulation could be a safer and non-invasive method to induce similar oxidative stress environments. The effect of ultrasound on cell viability and induction of oxidative stress increases with ultrasound intensity. The result reveals that the continuous ultrasound has a positive impact on the oxidative stress levels but does negatively on the cell viability, as compared to the pulsed ultrasound. Furthermore, our work demonstrates that the exposure of 58 kPa continuous ultrasound without microbubbles can maintain acceptable cell viability and produce oxidative stress effects similar to the traditional administrations of H2O2. In summary, exposure of ultrasound can generate oxidative stress comparable to traditional administrations of H2O2. The effect of generating oxidative stress is adjustable through ultrasound parameters, including the pulsed or continuous wave, the intensity of ultrasound and addition of microbubbles.

  17. Salidroside Suppresses HUVECs Cell Injury Induced by Oxidative Stress through Activating the Nrf2 Signaling Pathway.

    Science.gov (United States)

    Zhu, Yao; Zhang, Ya-Jie; Liu, Wei-Wei; Shi, Ai-Wu; Gu, Ning

    2016-08-09

    Oxidative stress plays an important role in the pathogenesis of cardiovascular diseases. Salidroside (SAL), one of the main effective constituents of Rhodiola rosea, has been reported to suppress oxidative stress-induced cardiomyocyte injury and necrosis by promoting transcription of nuclear factor E2-related factor 2 (Nrf2)-regulated genes such as heme oxygenase-1 (HO-1) and NAD(P)H dehydrogenase (quinone1) (NQO1). However, it has not been indicated whether SAL might ameliorate endothelial injury induced by oxidative stress. Here, our study demonstrated that SAL might suppress HUVEC cell injury induced by oxidative stress through activating the Nrf2 signaling pathway. The results of our study indicated that SAL decreased the levels of intercellular reactive oxygen species (ROS) and malondialdehyde (MDA), and improved the activities of superoxide dismutase (SOD) and catalase (CAT), resulting in protective effects against oxidative stress-induced cell damage in HUVECs. It suppressed oxidative stress damage by inducing Nrf2 nuclear translocation and activating the expression of Nrf2-regulated antioxidant enzyme genes such as HO-1 and NQO1 in HUVECs. Knockdown of Nrf2 with siRNA abolished the cytoprotective effects against oxidative stress, decreased the expression of Nrf2, HO-1, and NQO1, and inhibited the nucleus translocation of Nrf2 in HUVECs. This study is the first to demonstrate that SAL suppresses HUVECs cell injury induced by oxidative stress through activating the Nrf2 signaling pathway.

  18. Salidroside Suppresses HUVECs Cell Injury Induced by Oxidative Stress through Activating the Nrf2 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yao Zhu

    2016-08-01

    Full Text Available Oxidative stress plays an important role in the pathogenesis of cardiovascular diseases. Salidroside (SAL, one of the main effective constituents of Rhodiola rosea, has been reported to suppress oxidative stress-induced cardiomyocyte injury and necrosis by promoting transcription of nuclear factor E2-related factor 2 (Nrf2-regulated genes such as heme oxygenase-1 (HO-1 and NAD(PH dehydrogenase (quinone1 (NQO1. However, it has not been indicated whether SAL might ameliorate endothelial injury induced by oxidative stress. Here, our study demonstrated that SAL might suppress HUVEC cell injury induced by oxidative stress through activating the Nrf2 signaling pathway. The results of our study indicated that SAL decreased the levels of intercellular reactive oxygen species (ROS and malondialdehyde (MDA, and improved the activities of superoxide dismutase (SOD and catalase (CAT, resulting in protective effects against oxidative stress-induced cell damage in HUVECs. It suppressed oxidative stress damage by inducing Nrf2 nuclear translocation and activating the expression of Nrf2-regulated antioxidant enzyme genes such as HO-1 and NQO1 in HUVECs. Knockdown of Nrf2 with siRNA abolished the cytoprotective effects against oxidative stress, decreased the expression of Nrf2, HO-1, and NQO1, and inhibited the nucleus translocation of Nrf2 in HUVECs. This study is the first to demonstrate that SAL suppresses HUVECs cell injury induced by oxidative stress through activating the Nrf2 signaling pathway.

  19. Mitochondrial calcium uniporter protein MCU is involved in oxidative stress-induced cell death.

    Science.gov (United States)

    Liao, Yajin; Hao, Yumin; Chen, Hong; He, Qing; Yuan, Zengqiang; Cheng, Jinbo

    2015-06-01

    Mitochondrial calcium uniporter (MCU) is a conserved Ca(2+) transporter at mitochondrial in eukaryotic cells. However, the role of MCU protein in oxidative stress-induced cell death remains unclear. Here, we showed that ectopically expressed MCU is mitochondrial localized in both HeLa and primary cerebellar granule neurons (CGNs). Knockdown of endogenous MCU decreases mitochondrial Ca(2+) uptake following histamine stimulation and attenuates cell death induced by oxidative stress in both HeLa cells and CGNs. We also found MCU interacts with VDAC1 and mediates VDAC1 overexpression-induced cell death in CGNs. This finding demonstrates that MCU-VDAC1 complex regulates mitochondrial Ca(2+) uptake and oxidative stress-induced apoptosis, which might represent therapeutic targets for oxidative stress related diseases.

  20. Romo1 expression contributes to oxidative stress-induced death of lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jung Ar [Department of Internal Medicine, Yonsei University College of Medicine, Yonsei University Health System, Seoul 135-270 (Korea, Republic of); Chung, Jin Sil [Laboratory of Molecular Cell Biology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Cho, Sang-Ho [Department of Pathology, Pochon CHA University, College of Medicine, Gyeonggi-do (Korea, Republic of); Kim, Hyung Jung, E-mail: khj57@yuhs.ac.kr [Department of Internal Medicine, Yonsei University College of Medicine, Yonsei University Health System, Seoul 135-270 (Korea, Republic of); Yoo, Young Do, E-mail: ydy1130@korea.ac.kr [Laboratory of Molecular Cell Biology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of)

    2013-09-20

    Highlights: •Romo1 mediates oxidative stress-induced mitochondrial ROS production. •Romo1 induction by oxidative stress plays an important role in oxidative stress-induced apoptosis. •Romo1 overexpression correlates with epithelial cell death in patients with IPF. -- Abstract: Oxidant-mediated death of lung epithelial cells due to cigarette smoking plays an important role in pathogenesis in lung diseases such as idiopathic pulmonary fibrosis (IPF). However, the exact mechanism by which oxidants induce epithelial cell death is not fully understood. Reactive oxygen species (ROS) modulator 1 (Romo1) is localized in the mitochondria and mediates mitochondrial ROS production through complex III of the mitochondrial electron transport chain. Here, we show that Romo1 mediates mitochondrial ROS production and apoptosis induced by oxidative stress in lung epithelial cells. Hydrogen peroxide (H{sub 2}O{sub 2}) treatment increased Romo1 expression, and Romo1 knockdown suppressed the cellular ROS levels and cell death triggered by H{sub 2}O{sub 2} treatment. In immunohistochemical staining of lung tissues from patients with IPF, Romo1 was mainly localized in hyperplastic alveolar and bronchial epithelial cells. Romo1 overexpression was detected in 14 of 18 patients with IPF. TUNEL-positive alveolar epithelial cells were also detected in most patients with IPF but not in normal controls. These findings suggest that Romo1 mediates apoptosis induced by oxidative stress in lung epithelial cells.

  1. Pseudorabies Virus Induces Viability Changes and Oxidative Stress in Swine Testis Cell-Line

    Directory of Open Access Journals (Sweden)

    Xiao-Zhan Zhang§1, Ye Chen§1, Hong-Liang Huang§2, Dong-Lei Xu1, Chang-Bao Ren2, Bi-Tao Liu1, Shuo Su1 and Zhao-Xin Tang1, 2*

    2013-11-01

    Full Text Available In this study, we evaluated the association between pseudorabies (PRV virus-induced viability changes and oxidative stress in vitro cultivated swine testis (ST cells. The kinetic of 2, 12, 24, 36 and 48 h during the cell culture with PRV by using a multiplicity of infection (MOI of 1 TCID50 per cell were adopted. The results suggested a complex relation between cell viability and oxidative stress during PRV infection. In the early stages of PRV infection, the cell viability was higher than the control group, and the state of cellular oxidative stress remained relatively stable. After 24 h, the cell viability began to decrease, and the amount of the cellular malondialdehyde in ST cells increased significantly, and the activities of superoxide dismutase and catalase decreased significantly (P<0.05. Meanwhile, the rising concentrations of cellular hydrogen peroxide were detected prior to the changes in cell viability and oxidative stress. In conclusion, the PRV infection of ST cells leads to oxidative stress, and this stress could play a crucial role on the cell viability as the PRV infection time progresses.

  2. Tart Cherry Extracts Reduce Inflammatory and Oxidative Stress Signaling in Microglial Cells

    OpenAIRE

    Shukitt-Hale, Barbara; Megan E. Kelly; Donna F. Bielinski; Fisher, Derek R.

    2016-01-01

    Tart cherries contain an array of polyphenols that can decrease inflammation and oxidative stress (OS), which contribute to cognitive declines seen in aging populations. Previous studies have shown that polyphenols from dark-colored fruits can reduce stress-mediated signaling in BV-2 mouse microglial cells, leading to decreases in nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression. Thus, the present study sought to determine if tart cherries—which improved cogn...

  3. Oxidative Stress, Cell Death, and Other Damage to Alveolar Epithelial Cells Induced by Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Nagai A

    2003-09-01

    Full Text Available Abstract Cigarette smoking is a major risk factor in the development of various lung diseases, including pulmonary emphysema, pulmonary fibrosis, and lung cancer. The mechanisms of these diseases include alterations in alveolar epithelial cells, which are essential in the maintenance of normal alveolar architecture and function. Following cigarette smoking, alterations in alveolar epithelial cells induce an increase in epithelial permeability, a decrease in surfactant production, the inappropriate production of inflammatory cytokines and growth factors, and an increased risk of lung cancer. However, the most deleterious effect of cigarette smoke on alveolar epithelial cells is cell death, i.e., either apoptosis or necrosis depending on the magnitude of cigarette smoke exposure. Cell death induced by cigarette smoke exposure can largely be accounted for by an enhancement in oxidative stress. In fact, cigarette smoke contains and generates many reactive oxygen species that damage alveolar epithelial cells. Whether apoptosis and/or necrosis in alveolar epithelial cells is enhanced in healthy cigarette smokers is presently unclear. However, recent evidence indicates that the apoptosis of alveolar epithelial cells and alveolar endothelial cells is involved in the pathogenesis of pulmonary emphysema, an important cigarette smoke-induced lung disease characterized by the loss of alveolar structures. This review will discuss oxidative stress, cell death, and other damage to alveolar epithelial cells induced by cigarette smoke.

  4. Oxidative stress-induced epigenetic changes associated with malignant transformation of human kidney epithelial cells.

    Science.gov (United States)

    Mahalingaiah, Prathap Kumar S; Ponnusamy, Logeswari; Singh, Kamaleshwar P

    2016-09-17

    Renal Cell Carcinoma (RCC) in humans is positively influenced by oxidative stress status in kidneys. We recently reported that adaptive response to low level of chronic oxidative stress induces malignant transformation of immortalized human renal tubular epithelial cells. Epigenetic alterations in human RCC are well documented, but its role in oxidative stress-induced malignant transformation of kidney cells is not known. Therefore, the objective of this study was to evaluate the potential role of epigenetic changes in chronic oxidative stress-induced malignant transformation of HK-2, human renal tubular epithelial cells. The results revealed aberrant expression of epigenetic regulatory genes involved in DNA methylation (DNMT1, DNMT3a and MBD4) and histone modifications (HDAC1, HMT1 and HAT1) in HK-2 cells malignantly transformed by chronic oxidative stress. Additionally, both in vitro soft agar assay and in vivo nude mice study showing decreased tumorigenic potential of malignantly transformed HK-2 cells following treatment with DNA de-methylating agent 5-aza 2' dC further confirmed the crucial role of DNA hypermethyaltion in oxidative stress-induced malignant transformation. Changes observed in global histone H3 acetylation (H3K9, H3K18, H3K27 and H3K14) and decrease in phospho-H2AX (Ser139) also suggest potential role of histone modifications in increased survival and malignant transformation of HK-2 cells by oxidative stress. In summary, the results of this study suggest that epigenetic reprogramming induced by low levels of oxidative stress act as driver for malignant transformation of kidney epithelial cells. Findings of this study are highly relevant in potential clinical application of epigenetic-based therapeutics for treatments of kidney cancers.

  5. The Natural Polyphenol Epigallocatechin Gallate Protects Intervertebral Disc Cells from Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Olga Krupkova

    2016-01-01

    Full Text Available Oxidative stress-related phenotypic changes and a decline in the number of viable cells are crucial contributors to intervertebral disc degeneration. The polyphenol epigallocatechin 3-gallate (EGCG can interfere with painful disc degeneration by reducing inflammation, catabolism, and pain. In this study, we hypothesized that EGCG furthermore protects against senescence and/or cell death, induced by oxidative stress. Sublethal and lethal oxidative stress were induced in primary human intervertebral disc cells with H2O2 (total n=36. Under sublethal conditions, the effects of EGCG on p53-p21 activation, proliferative capacity, and accumulation of senescence-associated β-galactosidase were tested. Further, the effects of EGCG on mitochondria depolarization and cell viability were analyzed in lethal oxidative stress. The inhibitor LY249002 was applied to investigate the PI3K/Akt pathway. EGCG inhibited accumulation of senescence-associated β-galactosidase but did not affect the loss of proliferative capacity, suggesting that EGCG did not fully neutralize exogenous radicals. Furthermore, EGCG increased the survival of IVD cells in lethal oxidative stress via activation of prosurvival PI3K/Akt and protection of mitochondria. We demonstrated that EGCG not only inhibits inflammation but also can enhance the survival of disc cells in oxidative stress, which makes it a suitable candidate for the development of novel therapies targeting disc degeneration.

  6. Accelerated fat cell aging links oxidative stress and insulin resistance in adipocytes

    Indian Academy of Sciences (India)

    Finny Monickaraj; Sankaramoorthy Aravind; Pichamoorthy Nandhini; Paramasivam Prabu; Chandrakumar Sathishkumar; Viswanathan Mohan; Muthuswamy Balasubramanyam

    2013-03-01

    Telomere shortening is emerging as a biological indicator of accelerated aging and aging-related diseases including type 2 diabetes. While telomere length measurements were largely done in white blood cells, there is lack of studies on telomere length in relation to oxidative stress in target tissues affected in diabetes. Therefore, the aim of this study is to induct oxidative stress in adipocytes and to test whether these adipocytes exhibit shortened telomeres, senescence and functional impairment. 3T3-L1 adipocytes were subjected to oxidative stress and senescence induction by a variety of means for 2 weeks (exogenous application of H2O2, glucose oxidase, asymmetric dimethylarginine (ADMA) and glucose oscillations). Cells were probed for reactive oxygen species generation (ROS), DNA damage, mRNA and protein expression of senescent and pro-inflammatory markers, telomere length and glucose uptake. Compared to untreated cells, both ROS generation and DNA damage were significantly higher in cells subjected to oxidative stress and senescence. Adipocytes subjected to oxidative stress also showed shortened telomeres and increased mRNA and protein expression of p53, p21, TNF and IL-6. Senescent cells were also characterized by decreased levels of adiponectin and impaired glucose uptake. Briefly, adipocytes under oxidative stress exhibited increased ROS generation, DNA damage, shortened telomeres and switched to senescent/pro-inflammatory phenotype with impaired glucose uptake.

  7. Amnion-Epithelial-Cell-Derived Exosomes Demonstrate Physiologic State of Cell under Oxidative Stress.

    Directory of Open Access Journals (Sweden)

    Samantha Sheller

    Full Text Available At term, the signals of fetal maturity and feto-placental tissue aging prompt uterine readiness for delivery by transitioning quiescent myometrium to an active stage. It is still unclear how the signals reach the distant myometrium. Exosomes are a specific type of extracellular vesicle (EVs that transport molecular signals between cells, and are released from a wide range of cells, including the maternal and fetal cells. In this study, we hypothesize that i exosomes act as carriers of signals in utero-placental compartments and ii exosomes reflect the physiologic status of the origin cells. The primary aims of this study were to determine exosomal contents in exosomes derived from primary amnion epithelial cells (AEC. We also determined the effect of oxidative stress on AEC derived exosomal cargo contents. AEC were isolated from amniotic membrane obtained from normal, term, not in labor placentae at delivery, and culture under standard conditions. Oxidative stress was induced using cigarette smoke extract for 48 hours. AEC-conditioned media were collected and exosomes isolated by differential centrifugations. Both growth conditions (normal and oxidative stress induced produced cup shaped exosomes of around 50 nm, expressed exosomes enriched markers, such as CD9, CD63, CD81 and HSC70, embryonic stem cell marker Nanog, and contained similar amounts of cell free AEC DNA. Using confocal microscopy, the colocalization of histone (H 3, heat shock protein (HSP 70 and activated form of pro-senescence and term parturition associated marker p38 mitogen activated protein kinase (MAPK (P-p38 MAPK co-localized with exosome enrich marker CD9. HSP70 and P-p38 MAPK were significantly higher in exosomes from AEC grown under oxidative stress conditions than standard conditions (p<0.05. Finally, mass spectrometry and bioinformatics analysis identified 221 different proteins involved in immunomodulatory response and cell-to-cell communication. This study determined

  8. Effects of curcumin on bleomycin‑induced oxidative stress in malignant testicular germ cell tumors.

    Science.gov (United States)

    Cort, Aysegul; Ozdemir, Evrim; Timur, Mujgan; Ozben, Tomris

    2012-10-01

    Bleomycin is commonly used in the treatment of testicular cancer. Bleomycin generates oxygen radicals, induces the oxidative cleavage of DNA strands and induces cancer cell apoptosis. Curcumin (diferuloylmethane) is a potent antioxidant and chief component of the spice turmeric. No study investigating the effects of curcumin on intrinsic and bleomycin-induced oxidative stress in testicular germ cell tumors has been reported in the literature. For this reason, the present study aimed to examine the effects of curcumin on oxidative stress produced in wild-type NTera-2 and p53-mutant NCCIT testicular cancer cells incubated with bleomycin and the results were compared with cells treated with H2O2 which directly produces oxidative stress. The protein carbonyl content, thiobarbituric acid reactive substances (TBARS), glutathione (GSH), 8-isoprostane, lipid hydroperoxide (LPO) levels and total antioxidant capacity in the two testicular cancer cell lines were determined. Results showed that bleomycin and H2O2 significantly increased protein carbonyl, TBARS, 8-isoprostane and LPO levels in the NTera-2 and NCCIT cell lines. Bleomycin and H2O2 significantly decreased the antioxidant capacity and GSH levels in NTera-2 cells. Curcumin significantly decreased LPO, 8-isoprostane and protein carbonyl content, and TBARS levels increased in cells treated with bleomycin and H2O2. Curcumin enhanced GSH levels and the antioxidant capacity of NTera-2 cells. In conclusion, curcumin inhibits bleomycin and H2O2-induced oxidative stress in human testicular cancer cells.

  9. Determining adaptive and adverse oxidative stress responses in human bronical epithelial cells exposed to zinc

    Science.gov (United States)

    Determining adaptive and adverse oxidative stress responses in human bronchial epithelial cells exposed to zincJenna M. Currier1,2, Wan-Yun Cheng1, Rory Conolly1, Brian N. Chorley1Zinc is a ubiquitous contaminant of ambient air that presents an oxidant challenge to the human lung...

  10. Oxidative stress-associated senescence in dermal papilla cells of men with androgenetic alopecia.

    Science.gov (United States)

    Upton, James H; Hannen, Rosalind F; Bahta, Adiam W; Farjo, Nilofer; Farjo, Bessam; Philpott, Michael P

    2015-05-01

    Dermal papilla cells (DPCs) taken from male androgenetic alopecia (AGA) patients undergo premature senescence in vitro in association with the expression of p16(INK4a), suggesting that DPCs from balding scalp are more sensitive to environmental stress than nonbalding cells. As one of the major triggers of senescence in vitro stems from the cell "culture shock" owing to oxidative stress, we have further investigated the effects of oxidative stress on balding and occipital scalp DPCs. Patient-matched DPCs from balding and occipital scalp were cultured at atmospheric (21%) or physiologically normal (2%) O2. At 21% O2, DPCs showed flattened morphology and a significant reduction in mobility, population doubling, increased levels of reactive oxygen species and senescence-associated β-Gal activity, and increased expression of p16(INK4a) and pRB. Balding DPCs secreted higher levels of the negative hair growth regulators transforming growth factor beta 1 and 2 in response to H2O2 but not cell culture-associated oxidative stress. Balding DPCs had higher levels of catalase and total glutathione but appear to be less able to handle oxidative stress compared with occipital DPCs. These in vitro findings suggest that there may be a role for oxidative stress in the pathogenesis of AGA both in relation to cell senescence and migration but also secretion of known hair follicle inhibitory factors.

  11. Matrix metalloproteinase gene expressions might be oxidative stress targets in gastric cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Salih Gencer; Anil Cebeci; Meliha Burcu Irmak-Yazicioglu

    2013-01-01

    Objective:Oxidative stress is linked to increased risk of gastric cancer and matrix metalloproteinases (MMPs) are important in the invasion and metastasis of gastric cancer.We aimed to analyze the effect of the accumulation of oxidative stress in the gastric cancer MKN-45 and 23132/87 cells following hydrogen peroxide (H2O2) exposure on the expression patterns of MMP-1,MMP-3,MMP-7,MMP-9,MMP-10,MMP-11,MMP-12,MMP-14,MMP-15,MMP-17,MMP-23,MMP-28,and β-catenin genes.Methods:The mRNA transcripts in the cells were determined by RT-PCR.Following H2O2 exposure,oxidative stress in the viable cells was analyzed by 2',7'-dichlorofluorescein diacetate (DCFH-DA).Caffeic acid phenethyl ester (CAPE) was used to eliminate oxidative stress and the consequence of H2O2 exposure and its removal on the expressions of the genes were evaluated by quantitative real-time PCR.Results:The expressions of MMP-1,MMP-7,MMP-14,MMP-15,MMP-17 and β-catenin in MKN-45 cells and only the expression of MMP-15 in 23132/87 cells were increased.Removal of the oxidative stress resulted in decrease in the expressions of MMP genes of which the expressions were increased after H2O2 exposure.β-catenin,a transcription factor for many genes including MMPs,also displayed decreased levels of expression in both of the cell lines following CAPE treatment.Conclusions:Our data suggest that there is a remarkable link between the accumulation of oxidative stress and the increased expressions of MMP genes in the gastric cancer cells and MMPs should be considered as potential targets of therapy in gastric cancers due to its continuous exposure to oxidative stress.

  12. The role of DJ-1 in the oxidative stress cell death cascade after stroke

    Institute of Scientific and Technical Information of China (English)

    Paolina Pantcheva; Maya Elias; Kelsey Duncan; Cesar V.Borlongan; Naoki Tajiri; Yuji Kaneko

    2014-01-01

    Oxidative stress is closely associated with secondary cell death in many disorders of the central nervous system including stroke, Parkinson’s disease, Alzheimer’s disease. Among many aber-rant oxidative stress-associated proteins, DJ-1 has been associated with the oxidative stress cell death cascade primarily in Parkinson’s disease. Although principally expressed in the cytoplasm and nucleus, DJ-1 can be secreted into the serum under pathological condition. Recently, a close pathological association between DJ-1 and oxidative stress in stroke has been implicated. To this end, we and others have demonstrated the important role of mitochondria in neuroprotection for stroke by demonstrating that the translocation of DJ-1 in the mitochondria could potentially mitigate mitochondrial injury. Here, we discuss our recent ifndings testing the hypothesis that DJ-1 not only functions as a form of intracellular protection from oxidative stress, but that it also utilizes paracrine and/or autocrine cues in order to accomplish extracellular signaling between neighboring neuronal cells, resulting in neuroprotection. This article highlights recent evidence supporting the status of DJ-1 as key anti-oxidative stress therapeutic target for stroke.

  13. Oxidative Stress Type Influences the Properties of Antioxidants Containing Polyphenols in RINm5F Beta Cells

    Directory of Open Access Journals (Sweden)

    Nathalie Auberval

    2015-01-01

    Full Text Available The in vitro methods currently used to screen bioactive compounds focus on the use of a single model of oxidative stress. However, this simplistic view may lead to conflicting results. The aim of this study was to evaluate the antioxidant properties of two natural extracts (a mix of red wine polyphenols (RWPs and epigallocatechin gallate (EGCG with three models of oxidative stress induced with hydrogen peroxide (H2O2, a mixture of hypoxanthine and xanthine oxidase (HX/XO, or streptozotocin (STZ in RINm5F beta cells. We employed multiple approaches to validate their potential as therapeutic treatment options, including cell viability, reactive oxygen species production, and antioxidant enzymes expression. All three oxidative stresses induced a decrease in cell viability and an increase in apoptosis, whereas the level of ROS production was variable depending on the type of stress. The highest level of ROS was found for the HX/XO-induced stress, an increase that was reflected by higher expression antioxidant enzymes. Further, both antioxidant compounds presented beneficial effects during oxidative stress, but EGCG appeared to be a more efficient antioxidant. These data indicate that the efficiency of natural antioxidants is dependent on both the nature of the compound and the type of oxidative stress generated.

  14. Oxidative Stress Type Influences the Properties of Antioxidants Containing Polyphenols in RINm5F Beta Cells

    Science.gov (United States)

    Auberval, Nathalie; Dal, Stéphanie; Bietiger, William; Seyfritz, Elodie; Peluso, Jean; Muller, Christian; Zhao, Minjie; Marchioni, Eric; Pinget, Michel; Jeandidier, Nathalie; Maillard, Elisa; Schini-Kerth, Valérie; Sigrist, Séverine

    2015-01-01

    The in vitro methods currently used to screen bioactive compounds focus on the use of a single model of oxidative stress. However, this simplistic view may lead to conflicting results. The aim of this study was to evaluate the antioxidant properties of two natural extracts (a mix of red wine polyphenols (RWPs) and epigallocatechin gallate (EGCG)) with three models of oxidative stress induced with hydrogen peroxide (H2O2), a mixture of hypoxanthine and xanthine oxidase (HX/XO), or streptozotocin (STZ) in RINm5F beta cells. We employed multiple approaches to validate their potential as therapeutic treatment options, including cell viability, reactive oxygen species production, and antioxidant enzymes expression. All three oxidative stresses induced a decrease in cell viability and an increase in apoptosis, whereas the level of ROS production was variable depending on the type of stress. The highest level of ROS was found for the HX/XO-induced stress, an increase that was reflected by higher expression antioxidant enzymes. Further, both antioxidant compounds presented beneficial effects during oxidative stress, but EGCG appeared to be a more efficient antioxidant. These data indicate that the efficiency of natural antioxidants is dependent on both the nature of the compound and the type of oxidative stress generated. PMID:26508986

  15. Cerium fluoride nanoparticles protect cells against oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Shcherbakov, Alexander B.; Zholobak, Nadezhda M. [Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, Kyiv D0368 (Ukraine); Baranchikov, Alexander E. [Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); Ryabova, Anastasia V. [Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409 (Russian Federation); Ivanov, Vladimir K., E-mail: van@igic.ras.ru [Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); National Research Tomsk State University, Tomsk 634050 (Russian Federation)

    2015-05-01

    A novel facile method of non-doped and fluorescent terbium-doped cerium fluoride stable aqueous sols synthesis is proposed. Intense green luminescence of CeF{sub 3}:Tb nanoparticles can be used to visualize these nanoparticles' accumulation in cells using confocal laser scanning microscopy. Cerium fluoride nanoparticles are shown for the first time to protect both organic molecules and living cells from the oxidative action of hydrogen peroxide. Both non-doped and terbium-doped CeF{sub 3} nanoparticles are shown to provide noteworthy protection to cells against the vesicular stomatitis virus. - Highlights: • Facile method of CeF{sub 3} and CeF{sub 3}:Tb stable aqueous sols synthesis is proposed. • Naked CeF{sub 3} nanoparticles are shown to be non-toxic and to protect cells from the action of H{sub 2}O{sub 2}. • CeF{sub 3} and CeF{sub 3}:Tb nanoparticles are shown to protect living cells against the vesicular stomatitis virus.

  16. Beta Blockers Suppress Dextrose-Induced Endoplasmic Reticulum Stress, Oxidative Stress, and Apoptosis in Human Coronary Artery Endothelial Cells.

    Science.gov (United States)

    Haas, Michael J; Kurban, William; Shah, Harshit; Onstead-Haas, Luisa; Mooradian, Arshag D

    Beta blockers are known to have favorable effects on endothelial function partly because of their capacity to reduce oxidative stress. To determine whether beta blockers can also prevent dextrose-induced endoplasmic reticulum (ER) stress in addition to their antioxidative effects, human coronary artery endothelial cells and hepatocyte-derived HepG2 cells were treated with 27.5 mM dextrose for 24 hours in the presence of carvedilol (a lipophilic beta blockers with alpha blocking activity), propranolol (a lipophilic nonselective beta blockers), and atenolol (a water-soluble selective beta blockers), and ER stress, oxidative, stress and cell death were measured. ER stress was measured using the placental alkaline phosphatase assay and Western blot analysis of glucose regulated protein 78, c-Jun-N-terminal kinase (JNK), phospho-JNK, eukaryotic initiating factor 2α (eIF2α), and phospho-eIF2α and measurement of X-box binding protein 1 (XBP1) mRNA splicing using reverse transcriptase-polymerase chain reaction. Superoxide (SO) generation was measured using the superoxide-reactive probe 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride (MCLA) chemiluminescence. Cell viability was measured by propidium iodide staining method. The ER stress, SO production, and cell death induced by 27.5 mM dextrose were inhibited by all 3 beta blockers tested. The antioxidative and ER stress reducing effects of beta blockers were also observed in HepG2 cells. The salutary effects of beta blockers on endothelial cells in reducing both ER stress and oxidative stress may contribute to the cardioprotective effects of these agents.

  17. Toxicity and oxidative stress of canine mesenchymal stromal cells from adipose tissue in different culture passages

    Directory of Open Access Journals (Sweden)

    Arícia Gomes Sprada

    2015-12-01

    Full Text Available Abstract: Stem cells in regenerative therapy have received attention from researchers in recent decades. The culture of these cells allows studies about their behavior and metabolism. Thus, cell culture is the basis for cell therapy and tissue engineering researches. A major concern regarding the use of cultivated stem cell in human or veterinary clinical routine is the risk of carcinogenesis. Cellular activities require a balanced redox state. However, when there is an imbalance in this state, oxidative stress occurs. Oxidative stress contributes to cytotoxicity, which may result in cell death or genomic alterations, favoring the development of cancer cells. The aim of this study was to determine whether there are differences in the behavior of cultured mesenchymal stem cells from canine adipose tissue according to its site of collection (omentum and subcutaneous evaluating the rate of proliferation, viability, level of oxidative stress and cytotoxicity over six passages. For this experiment, two samples of adipose tissue from subcutaneous and omentum where taken from a female dog corpse, 13 years old, Pitbull. The results showed greater levels of oxidative stress in the first and last passages of both groups, favoring cytotoxicity and cell death.

  18. Comparative expression profiling of distinct T cell subsets undergoing oxidative stress.

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    Rudolf Lichtenfels

    Full Text Available The clinical outcome of adoptive T cell transfer-based immunotherapies is often limited due to different escape mechanisms established by tumors in order to evade the hosts' immune system. The establishment of an immunosuppressive micromilieu by tumor cells along with distinct subsets of tumor-infiltrating lymphocytes is often associated with oxidative stress that can affect antigen-specific memory/effector cytotoxic T cells thereby substantially reducing their frequency and functional activation. Therefore, protection of tumor-reactive cytotoxic T lymphocytes from oxidative stress may enhance the anti-tumor-directed immune response. In order to better define the key pathways/proteins involved in the response to oxidative stress a comparative 2-DE-based proteome analysis of naïve CD45RA(+ and their memory/effector CD45RO(+ T cell counterparts in the presence and absence of low dose hydrogen peroxide (H(2O(2 was performed in this pilot study. Based on the profiling data of these T cell subpopulations under the various conditions, a series of differentially expressed spots were defined, members thereof identified by mass spectrometry and subsequently classified according to their cellular function and localization. Representative targets responding to oxidative stress including proteins involved in signaling pathways, in regulating the cellular redox status as well as in shaping/maintaining the structural cell integrity were independently verified at the transcript and protein level under the same conditions in both T cell subsets. In conclusion the resulting profiling data describe complex, oxidative stress-induced, but not strictly concordant changes within the respective expression profiles of CD45RA(+ and CD45RO(+ T cells. Some of the differentially expressed genes/proteins might be further exploited as potential targets toward modulating the redox capacity of the distinct lymphocyte subsets thereby providing the basis for further studies

  19. Inflammatory cytokines protect retinal pigment epithelial cells from oxidative stress-induced death

    DEFF Research Database (Denmark)

    Juel, Helene B; Faber, Carsten; Svendsen, Signe Goul

    2013-01-01

    -mediated induction of the anti-oxidative stress response, upregulating protective anti-oxidant pathway(s). These findings suggest caution for the clinical use of anti-inflammatory agents in the management of immune-associated eye diseases such as age-related macular degeneration.......PURPOSE: To investigate the effects of inflammatory factors and oxidative stress on cell survival of the human retinal pigment epithelial (RPE) cell line, ARPE-19. METHODS: Confluent RPE cells were treated with peripheral blood mononuclear cells-conditioned medium (PCM), H2O2, NaIO3, interferon...... (IFN)-γ, tumor necrosis factor (TNF)-α, or combinations of these. Cell viability was determined by viability assays and by light microscopy. Effector molecules of cell death were investigated by immunofluorescence microscopy and flow cytometry. Microarrays were performed to screen for differential...

  20. Natural resistance to ascorbic acid induced oxidative stress is mainly mediated by catalase activity in human cancer cells and catalase-silencing sensitizes to oxidative stress

    Directory of Open Access Journals (Sweden)

    Klingelhoeffer Christoph

    2012-05-01

    Full Text Available Abstract Background Ascorbic acid demonstrates a cytotoxic effect by generating hydrogen peroxide, a reactive oxygen species (ROS involved in oxidative cell stress. A panel of eleven human cancer cell lines, glioblastoma and carcinoma, were exposed to serial dilutions of ascorbic acid (5-100 mmol/L. The purpose of this study was to analyse the impact of catalase, an important hydrogen peroxide-detoxifying enzyme, on the resistance of cancer cells to ascorbic acid mediated oxidative stress. Methods Effective concentration (EC50 values, which indicate the concentration of ascorbic acid that reduced the number of viable cells by 50%, were detected with the crystal violet assay. The level of intracellular catalase protein and enzyme activity was determined. Expression of catalase was silenced by catalase-specific short hairpin RNA (sh-RNA in BT-20 breast carcinoma cells. Oxidative cell stress induced apoptosis was measured by a caspase luminescent assay. Results The tested human cancer cell lines demonstrated obvious differences in their resistance to ascorbic acid mediated oxidative cell stress. Forty-five percent of the cell lines had an EC50 > 20 mmol/L and fifty-five percent had an EC50 50 of 2.6–5.5 mmol/L, glioblastoma cells were the most susceptible cancer cell lines analysed in this study. A correlation between catalase activity and the susceptibility to ascorbic acid was observed. To study the possible protective role of catalase on the resistance of cancer cells to oxidative cell stress, the expression of catalase in the breast carcinoma cell line BT-20, which cells were highly resistant to the exposure to ascorbic acid (EC50: 94,9 mmol/L, was silenced with specific sh-RNA. The effect was that catalase-silenced BT-20 cells (BT-20 KD-CAT became more susceptible to high concentrations of ascorbic acid (50 and 100 mmol/L. Conclusions Fifty-five percent of the human cancer cell lines tested were unable to protect themselves

  1. Endothelial cell activation, oxidative stress and inflammation induced by a panel of metal-based nanomaterials

    DEFF Research Database (Denmark)

    Danielsen, Pernille Høgh; Cao, Yi; Roursgaard, Martin;

    2015-01-01

    The importance of composition, size, crystal structure, charge and coating of metal-based nanomaterials (NMs) were evaluated in human umbilical vein endothelial cells (HUVECs) and/or THP-1 monocytic cells. Biomarkers of oxidative stress and inflammation were assessed because they are important...

  2. Effects of resveratrol on hydrogen peroxide-induced oxidative stress in embryonic neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Sibel Konyalioglu; Guliz Armagan; Ayfer Yalcin; Cigdem Atalayin; Taner Dagci

    2013-01-01

    Resveratrol, a natural phenolic compound, has been shown to prevent cardiovascular diseases and cancer and exhibit neuroprotective effects. In this study, we examined the neuroprotective and antioxidant effects of resveratrol against hydrogen peroxide in embryonic neural stem cells. Hydrogen peroxide treatment alone increased catalase and glutathione peroxidase activities but did not change superoxide dismutase levels compared with hydrogen peroxide + resveratrol treatment. Nitric oxide synthase activity and concomitant nitric oxide levels increased in response to hydrogen peroxide treatment. Conversely, resveratrol treatment decreased nitric oxide synthase activity and nitric oxide levels. Resveratrol also attenuated hydrogen peroxide-induced nuclear or mitochondrial DNA damage. We propose that resveratrol may be a promising agent for protecting embryonic neural stem cells because of its potential to decrease oxidative stress by inducing higher activity of antioxidant enzymes, decreasing nitric oxide production and nitric oxide synthase activity, and alleviating both nuclear and mitochondrial DNA damage.

  3. Mono-2-ethylhexyl phthalate induces oxidative stress responses in human placental cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Tetz, Lauren M., E-mail: ltetz@umich.edu [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (United States); Cheng, Adrienne A.; Korte, Cassandra S. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (United States); Giese, Roger W.; Wang, Poguang [Department of Pharmaceutical Sciences, Northeastern University, 360 Huntingon Ave, Boston, MA 02115 (United States); Harris, Craig; Meeker, John D.; Loch-Caruso, Rita [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (United States)

    2013-04-01

    Di-2-ethylhexyl phthalate (DEHP) is an environmental contaminant commonly used as a plasticizer in polyvinyl chloride products. Exposure to DEHP has been linked to adverse pregnancy outcomes in humans including preterm birth, low birth-weight, and pregnancy loss. Although oxidative stress is linked to the pathology of adverse pregnancy outcomes, effects of DEHP metabolites, including the active metabolite, mono-2-ethylhexyl phthalate (MEHP), on oxidative stress responses in placental cells have not been previously evaluated. The objective of the current study is to identify MEHP-stimulated oxidative stress responses in human placental cells. We treated a human placental cell line, HTR-8/SVneo, with MEHP and then measured reactive oxygen species (ROS) generation using the dichlorofluorescein assay, oxidized thymine with mass-spectrometry, redox-sensitive gene expression with qRT-PCR, and apoptosis using a luminescence assay for caspase 3/7 activity. Treatment of HTR-8 cells with 180 μM MEHP increased ROS generation, oxidative DNA damage, and caspase 3/7 activity, and resulted in differential expression of redox-sensitive genes. Notably, 90 and 180 μM MEHP significantly induced mRNA expression of prostaglandin-endoperoxide synthase 2 (PTGS2), an enzyme important for synthesis of prostaglandins implicated in initiation of labor. The results from the present study are the first to demonstrate that MEHP stimulates oxidative stress responses in placental cells. Furthermore, the MEHP concentrations used were within an order of magnitude of the highest concentrations measured previously in human umbilical cord or maternal serum. The findings from the current study warrant future mechanistic studies of oxidative stress, apoptosis, and prostaglandins as molecular mediators of DEHP/MEHP-associated adverse pregnancy outcomes. - Highlights: ► MEHP increased reactive oxygen species, oxidative DNA damage, and caspase activity. ► MEHP induced expression of PTGS2, a gene

  4. ATM regulation of IL-8 links oxidative stress to cancer cell migration and invasion.

    Science.gov (United States)

    Chen, Wei-Ta; Ebelt, Nancy D; Stracker, Travis H; Xhemalce, Blerta; Van Den Berg, Carla L; Miller, Kyle M

    2015-06-01

    Ataxia-telangiectasia mutated (ATM) protein kinase regulates the DNA damage response (DDR) and is associated with cancer suppression. Here we report a cancer-promoting role for ATM. ATM depletion in metastatic cancer cells reduced cell migration and invasion. Transcription analyses identified a gene network, including the chemokine IL-8, regulated by ATM. IL-8 expression required ATM and was regulated by oxidative stress. IL-8 was validated as an ATM target by its ability to rescue cell migration and invasion defects in ATM-depleted cells. Finally, ATM-depletion in human breast cancer cells reduced lung tumors in a mouse xenograft model and clinical data validated IL-8 in lung metastasis. These findings provide insights into how ATM activation by oxidative stress regulates IL-8 to sustain cell migration and invasion in cancer cells to promote metastatic potential. Thus, in addition to well-established roles in tumor suppression, these findings identify a role for ATM in tumor progression.

  5. Effect of zinc and nitric oxide on monocyte adhesion to endothelial cells under shear stress.

    Science.gov (United States)

    Lee, Sungmun; Eskin, Suzanne G; Shah, Ankit K; Schildmeyer, Lisa A; McIntire, Larry V

    2012-03-01

    This study describes the effect of zinc on monocyte adhesion to endothelial cells under different shear stress regimens, which may trigger atherogenesis. Human umbilical vein endothelial cells were exposed to steady shear stress (15 dynes/cm(2) or 1 dyne/cm(2)) or reversing shear stress (time average 1 dyne/cm(2)) for 24 h. In all shear stress regimes, zinc deficiency enhanced THP-1 cell adhesion, while heparinase III reduced monocyte adhesion following reversing shear stress exposure. Unlike other shear stress regimes, reversing shear stress alone enhanced monocyte adhesion, which may be associated with increased H(2)O(2) and superoxide together with relatively low levels of nitric oxide (NO) production. L-N(G)-Nitroarginine methyl ester (L-NAME) treatment increased monocyte adhesion under 15 dynes/cm(2) and under reversing shear stress. After reversing shear stress, monocyte adhesion dramatically increased with heparinase III treatment followed by a zinc scavenger. Static culture experiments supported the reduction of monocyte adhesion by zinc following endothelial cell cytokine activation. These results suggest that endothelial cell zinc levels are important for the inhibition of monocyte adhesion to endothelial cells, and may be one of the key factors in the early stages of atherogenesis.

  6. Increased Oxidative Stress in Cultured 3T3-L1 Cells was Attenuated by Berberine Treatment.

    Science.gov (United States)

    Dong, Shi-Fen; Yasui, Naomi; Negishb, Hiroko; Kishimoto, Aya; Sun, Jian-Ning; Ikeda, Katsumi

    2015-06-01

    The 3T3-L1 cell line is one of the most well-characterized and reliable models for studying adipocytes. Increased oxidative stress in accumulated fat was found in 3T3-L1 cells. Berberine, an isoquinoline alkaloid, could suppress fat deposition in 3T3-L1 cells; however, whether berberine suppresses increased oxidative stress is not well known. In this study, we observed the effect of berberine on increased oxidative stress in 3T3-L1 cells. 3T3-L1 cells were cultured and treated with berberine (5-20 μM) from day 3 to day 8. We confirmed that berberine markedly inhibited fat accumulation and lipid droplets in 3T3-L1 adipocytes and decreased triglyceride content. Berberine inhibited increased oxidative stress in 3T3-L1 cells by suppressing reactive oxygen species (ROS) production, and increased glutathione peroxidase (GPx) gene expression and GPx activity. Berberine also markedly reduced adipokines secreted by adipocytes, including leptin and resistin.

  7. Decreased cell proliferation and higher oxidative stress in fibroblasts from Down Syndrome fetuses. Preliminary study.

    Science.gov (United States)

    Gimeno, Amparo; García-Giménez, José Luis; Audí, Laura; Toran, Nuria; Andaluz, Pilar; Dasí, Francisco; Viña, José; Pallardó, Federico V

    2014-01-01

    Down Syndrome is the most common chromosomal disease and is also known for its decreased incidence of solid tumors and its progeroid phenotype. Cellular and systemic oxidative stress has been considered as one of the Down Syndrome phenotype causes. We correlated, in a preliminary study, the fibroblast proliferation rate and different cell proliferation key regulators, like Rcan1 and the telomere length from Down Syndrome fetuses, with their oxidative stress profile and the Ribonucleic acid and protein expression of the main antioxidant enzymes together with their activity. Increased oxidized glutathione/glutathione ratio and high peroxide production were found in our cell model. These results correlated with a distorted antioxidant shield. The messenger RNA (SOD1) and protein levels of copper/zinc superoxide dismutase were increased together with a decreased mRNA expression and protein levels of glutathione peroxidase (GPx). As a consequence the [Cu/ZnSOD/(catalase+GPx)] activity ratio increases which explains the oxidative stress generated in the cell model. In addition, the expression of thioredoxin 1 and glutaredoxin 1 is decreased. The results obtained show a decreased antioxidant phenotype that correlates with increased levels of Regulator of calcineurin 1 and attrition of telomeres, both related to oxidative stress and cell cycle impairment. Our preliminary results may explain the proneness to a progeroid phenotype.

  8. Protective effect of wheat peptides against indomethacin-induced oxidative stress in IEC-6 cells.

    Science.gov (United States)

    Yin, Hong; Pan, Xingchang; Song, Zhixiu; Wang, Shaokang; Yang, Ligang; Sun, Guiju

    2014-01-29

    Recent studies have demonstrated that wheat peptides protected rats against non-steroidal anti-inflammatory drugs-induced small intestinal epithelial cells damage, but the mechanism of action is unclear. In the present study, an indomethacin-induced oxidative stress model was used to investigate the effect of wheat peptides on the nuclear factor-κB(NF-κB)-inducible nitric oxide synthase-nitric oxide signal pathway in intestinal epithelial cells-6 cells. IEC-6 cells were treated with wheat peptides (0, 125, 500 and 2000 mg/L) for 24 h, followed by 90 mg/L indomethacin for 12 h. Wheat peptides significantly attenuated the indomethacin-induced decrease in superoxide dismutase and glutathione peroxidase activity. Wheat peptides at 2000 mg/L markedly decreased the expression of the NF-κB in response to indomethacin-induced oxidative stress. This study demonstrated that the addition of wheat peptides to a culture medium significantly inhibited the indomethacin-induced release of malondialdehyde and nitrogen monoxide, and increased antioxidant enzyme activity in IEC-6 cells, thereby providing a possible explanation for the protective effect proposed for wheat peptides in the prevention of indomethacin-induced oxidative stress in small intestinal epithelial cells.

  9. Protective Effect of Wheat Peptides against Indomethacin-Induced Oxidative Stress in IEC-6 Cells

    Directory of Open Access Journals (Sweden)

    Hong Yin

    2014-01-01

    Full Text Available Recent studies have demonstrated that wheat peptides protected rats against non-steroidal anti-inflammatory drugs-induced small intestinal epithelial cells damage, but the mechanism of action is unclear. In the present study, an indomethacin-induced oxidative stress model was used to investigate the effect of wheat peptides on the nuclear factor-κB(NF-κB-inducible nitric oxide synthase-nitric oxide signal pathway in intestinal epithelial cells-6 cells. IEC-6 cells were treated with wheat peptides (0, 125, 500 and 2000 mg/L for 24 h, followed by 90 mg/L indomethacin for 12 h. Wheat peptides significantly attenuated the indomethacin-induced decrease in superoxide dismutase and glutathione peroxidase activity. Wheat peptides at 2000 mg/L markedly decreased the expression of the NF-κB in response to indomethacin-induced oxidative stress. This study demonstrated that the addition of wheat peptides to a culture medium significantly inhibited the indomethacin-induced release of malondialdehyde and nitrogen monoxide, and increased antioxidant enzyme activity in IEC-6 cells, thereby providing a possible explanation for the protective effect proposed for wheat peptides in the prevention of indomethacin-induced oxidative stress in small intestinal epithelial cells.

  10. Lysosome dysfunction enhances oxidative stress-induced apoptosis through ubiquitinated protein accumulation in Hela cells.

    Science.gov (United States)

    Yu, Chunyan; Huang, Xiaowei; Xu, Ye; Li, Hongyan; Su, Jing; Zhong, Jiateng; Kang, Jinsong; Liu, Yuhe; Sun, Liankun

    2013-01-01

    The role of lysosomal system in oxidative stress-induced apoptosis in cancer cells is not fully understood. Menadione is frequently used as oxidative stress model. It is indicated that menadione could induce autophagy in Hela cells. In the present study, we examined whether the lysosomal inhibitor, ammonium chloride (NH(4)Cl) could prevent the autophagy flux by inhibiting the fusion of autophagosomes with lysosomes and enhance apoptosis induced by menadione via mitochondrial pathway. The results demonstrated generation and accumulation of reactive oxygen species and increased levels of ubiquitinated proteins and GRP78 in cells treated with both menadione and NH(4)Cl. Our data indicates that lysosomal system through autophagy plays an important role in preventing menadione-induced apoptosis in Hela cells by clearing misfolded proteins, which alleviates endoplasmic reticulum stress.

  11. Downregulation of miR-205 modulates cell susceptibility to oxidative and endoplasmic reticulum stresses in renal tubular cells.

    Directory of Open Access Journals (Sweden)

    Shiyo Muratsu-Ikeda

    Full Text Available BACKGROUND: Oxidative stress and endoplasmic reticulum (ER stress play a crucial role in tubular damage in both acute kidney injury (AKI and chronic kidney disease (CKD. While the pathophysiological contribution of microRNAs (miRNA to renal damage has also been highlighted, the effect of miRNA on renal damage under oxidative and ER stresses conditions remains elusive. METHODS: We assessed changes in miRNA expression in the cultured renal tubular cell line HK-2 under hypoxia-reoxygenation-induced oxidative stress or ER stress using miRNA microarray assay and real-time RT-PCR. The pathophysiological effect of miRNA was evaluated by cell survival rate, intracellular reactive oxygen species (ROS level, and anti-oxidant enzyme expression in miRNA-inhibited HK-2 or miRNA-overexpressed HK-2 under these stress conditions. The target gene of miRNA was identified by 3'-UTR-luciferase assay. RESULTS: We identified 8 and 10 miRNAs whose expression was significantly altered by oxidative and ER stresses, respectively. Among these, expression of miR-205 was markedly decreased in both stress conditions. Functional analysis revealed that decreased miR-205 led to an increase in cell susceptibility to oxidative and ER stresses, and that this increase was associated with the induction of intracellular ROS and suppression of anti-oxidant enzymes. While increased miR-205 by itself made no change in cell growth or morphology, cell viability under oxidative or ER stress conditions was partially restored. Further, miR-205 bound to the 3'-UTR of the prolyl hydroxylase 1 (PHD1/EGLN2 gene and suppressed the transcription level of EGLN2, which modulates both intracellular ROS level and ER stress state. CONCLUSIONS: miR-205 serves a protective role against both oxidative and ER stresses via the suppression of EGLN2 and subsequent decrease in intracellular ROS. miR-205 may represent a novel therapeutic target in AKI and CKD associated with oxidative or ER stress in tubules.

  12. Oxidative Stress Induces Endothelial Cell Senescence via Downregulation of Sirt6

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    Rong Liu

    2014-01-01

    Full Text Available Accumulating evidence has shown that diabetes accelerates aging and endothelial cell senescence is involved in the pathogenesis of diabetic vascular complications, including diabetic retinopathy. Oxidative stress is recognized as a key factor in the induction of endothelial senescence and diabetic retinopathy. However, specific mechanisms involved in oxidative stress-induced endothelial senescence have not been elucidated. We hypothesized that Sirt6, which is a nuclear, chromatin-bound protein critically involved in many pathophysiologic processes such as aging and inflammation, may have a role in oxidative stress-induced vascular cell senescence. Measurement of Sirt6 expression in human endothelial cells revealed that H2O2 treatment significantly reduced Sirt6 protein. The loss of Sirt6 was associated with an induction of a senescence phenotype in endothelial cells, including decreased cell growth, proliferation and angiogenic ability, and increased expression of senescence-associated β-galactosidase activity. Additionally, H2O2 treatment reduced eNOS expression, enhanced p21 expression, and dephosphorylated (activated retinoblastoma (Rb protein. All of these alternations were attenuated by overexpression of Sirt6, while partial knockdown of Sirt6 expression by siRNA mimicked the effect of H2O2. In conclusion, these results suggest that Sirt6 is a critical regulator of endothelial senescence and oxidative stress-induced downregulation of Sirt6 is likely involved in the pathogenesis of diabetic retinopathy.

  13. Complete relaxation of residual stresses during reduction of solid oxide fuel cells

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

    2015-01-01

    reduce significantly over minutes. In this work the stresses are measured in-situ before and after the reduction by use of XRD. The phenomenon of accelerated creep has to be considered both in the production of stacks and in the analysis of the stress field in a stack based on anode supported SOFCs.......To asses the reliability of solid oxide fuel cell (SOFC) stacks during operation, the stress field in the stack must be known. During operation the stress field will depend on time as creep processes relax stresses. This work reports further details on a newly discovered creep phenomenon......, accelerated creep, taking place during the reduction of the anode. This relaxes stresses at a much higher rate (~×104) than creep during operation. The phenomenon has previously been studied by simultaneous loading and reduction. With the recorded high creep rates, the stresses at the time of reduction should...

  14. Puerarin prevents high glucose-induced apoptosis of Schwann cells by inhibiting oxidative stress

    Institute of Scientific and Technical Information of China (English)

    Yingying Wu; Bing Xue; Xiaojin Li; Hongchen Liu

    2012-01-01

    Oxidative stress may be the unifying factor for the injury caused by hyperglycemia in diabeticperipheral neuropathy.Puerarin is the major isoflavonoid derived from Radix puerariae and has been shown to be effective in increasing superoxide dismutase activity.This study sought to investigate the neuroprotective effect of puerarin on high glucose-induced oxidative stress and Schwann cell apoptosis in vitro.Intracellular reactive oxygen radicals and mitochondrial transmembrane potential were detected by flow cytometry analysis.Apoptosis was confirmed by TUNEL and oxidative stress was monitored using an enzyme-linked immunosorbent assay for the DNA marker 8-hydroxy-2-deoxyguanosine.The expression levels of bax and bcl-2 were analyzed by quantitative real-time reverse transcriptase-PCR,while protein expression of cleaved caspase-3 and-9 were analyzed by means of western blotting.Results suggested that puerarin treatment inhibited high glucose-induced oxidative stress,mitochondrial depolarization and apoptosis in a dose-dependent manner.Furthermore,puerarin treatment downregulated Bax expression,upregulated bcl-2 expression and attenuated the activation of caspase-3 and-9.Overall,our results indicated that puerarin antagonized high glucose-induced oxidative stress and apoptosis in Schwann cells.

  15. Protective effect of hydroxytyrosol and tyrosol against oxidative stress in kidney cells.

    Science.gov (United States)

    Loru, D; Incani, A; Deiana, M; Corona, G; Atzeri, A; Melis, M P; Rosa, A; Dessì, M A

    2009-01-01

    Bioavailability studies in animals and humans fed with extravirgin olive oil demonstrated that hydroxytyrosol and tyrosol, the major simple phenolic compounds in extravirgin olive oil, are dose-dependently absorbed and excreted. Once absorbed, they undergo extensive metabolism; hydroxytyrosol and tyrosol concentrate mainly in the kidney, where they may exert an important role in the prevention of oxidative stress induced renal dysfunction. In this study we monitored the ability of hydroxytyrosol and tyrosol to protect renal cells (LLC-PK1) following oxidative damage induced by H2O2. Oxidative stress was evaluated by monitoring the changes of the membrane lipid fraction. Hydroxytyrosol exerted a significant antioxidant action, inhibiting the production of MDA, fatty acids hydroperoxides and 7-ketocholesterol, major oxidation products of unsaturated fatty acids and cholesterol, and thus protecting the cells from H2O2-induced damage. Tyrosol, instead, in this experimental model, did not exert any protective effect.

  16. Cytotoxicity of citral against melanoma cells: The involvement of oxidative stress generation and cell growth protein reduction.

    Science.gov (United States)

    Sanches, Larissa Juliani; Marinello, Poliana Camila; Panis, Carolina; Fagundes, Tatiane Renata; Morgado-Díaz, José Andrés; de-Freitas-Junior, Julio Cesar Madureira; Cecchini, Rubens; Cecchini, Alessandra Lourenço; Luiz, Rodrigo Cabral

    2017-03-01

    Citral is a natural compound that has shown cytotoxic and antiproliferative effects on breast and hematopoietic cancer cells; however, there are few studies on melanoma cells. Oxidative stress is known to be involved in all stages of melanoma development and is able to modulate intracellular pathways related to cellular proliferation and death. In this study, we hypothesize that citral exerts its cytotoxic effect on melanoma cells by the modulation of cellular oxidative status and/or intracellular signaling. To test this hypothesis, we investigated the antiproliferative and cytotoxic effects of citral on B16F10 murine melanoma cells evaluating its effects on cellular oxidative stress, DNA damage, cell death, and important signaling pathways, as these pathways, namely, extracellular signal-regulated kinases 1/2 (ERK1/2), AKT, and phosphatidylinositol-3 kinase, are involved in cell proliferation and differentiation. The p53 and nuclear factor kappa B were also investigated due to their ability to respond to intracellular stress. We observed that citral exerted antiproliferative and cytotoxic effects in B16F10; induced oxidative stress, DNA lesions, and p53 nuclear translocation; and reduced nitric oxide levels and nuclear factor kappa B, ERK1/2, and AKT. To investigate citral specificity, we used non-neoplastic human and murine cells, HaCaT (human skin keratinocytes) and NIH-3T3 cells (murine fibroblasts), and observed that although citral effects were not specific for cancer cells, non-neoplastic cells were more resistant to citral than B16F10. These findings highlight the potential clinical utility of citral in melanoma, with a mechanism of action involving the oxidative stress generation, nitric oxide depletion, and interference in signaling pathways related to cell proliferation.

  17. Impact of oxidative stress on Acanthamoeba castellanii mitochondrial bioenergetics depends on cell growth stage.

    Science.gov (United States)

    Woyda-Ploszczyca, Andrzej; Koziel, Agnieszka; Antos-Krzeminska, Nina; Jarmuszkiewicz, Wieslawa

    2011-06-01

    Addition of a moderate (1.4 mM) concentration of H(2)O(2) to protozoon Acanthamoeba castellanii cell cultures at different growth phases caused a different response to oxidative stress. H(2)O(2) treatment of exponentially growing cells significantly delayed their growth; however, in mitochondria isolated from these cells, no damage to their bioenergetic function was observed. In contrast, addition of H(2)O(2) to A. castellanii cells approaching the stationary phase did not influence their growth and viability while seriously affecting mitochondrial bioenergetic function. Although mitochondrial integrity was maintained, oxidative damage was revealed in the reduction of cytochrome pathway activity, uncoupling protein activity, and the efficiency of oxidative phosphorylation as well as the membrane potential and the endogenous ubiquinone reduction level of the resting state. An increase in the alternative oxidase protein level and activity as well as an increase in the membranous ubiquinone content were observed in mitochondria isolated from late H(2)O(2)-treated cells. For the first time, the regulation of ubiquinone content in the inner mitochondrial membrane is shown to play a role in the response to oxidative stress. A physiological role for the higher activity of the alternative oxidase in response to oxidative stress in unicellular organisms, such as amoeba A. castellanii, is discussed.

  18. Curcumin targeting the thioredoxin system elevates oxidative stress in HeLa cells.

    Science.gov (United States)

    Cai, Wenqing; Zhang, Baoxin; Duan, Dongzhu; Wu, Jincai; Fang, Jianguo

    2012-08-01

    The thioredoxin system, composed of thioredoxin reductase (TrxR), thioredoxin (Trx), and NADPH, is ubiquitous in all cells and involved in many redox-dependent signaling pathways. Curcumin, a naturally occurring pigment that gives a specific yellow color in curry food, is consumed in normal diet up to 100mg per day. This molecule has also been used in traditional medicine for the treatment of a variety of diseases. Curcumin has numerous biological functions, and many of these functions are related to induction of oxidative stress. However, how curcumin elicits oxidative stress in cells is unclear. Our previous work has demonstrated the way by which curcumin interacts with recombinant TrxR1 and alters the antioxidant enzyme into a reactive oxygen species (ROS) generator in vitro. Herein we reported that curcumin can target the cytosolic/nuclear thioredoxin system to eventually elevate oxidative stress in HeLa cells. Curcumin-modified TrxR1 dose-dependently and quantitatively transfers electrons from NADPH to oxygen with the production of ROS. Also, curcumin can drastically down-regulate Trx1 protein level as well as its enzyme activity in HeLa cells, which in turn remarkably decreases intracellular free thiols, shifting the intracellular redox balance to a more oxidative state, and subsequently induces DNA oxidative damage. Furthermore, curcumin-pretreated HeLa cells are more sensitive to oxidative stress. Knockdown of TrxR1 sensitizes HeLa cells to curcumin cytotoxicity, highlighting the physiological significance of targeting TrxR1 by curcumin. Taken together, our data disclose a previously unrecognized prooxidant mechanism of curcumin in cells, and provide a deep insight in understanding how curcumin works in vivo.

  19. Dichloroacetate Decreases Cell Health and Activates Oxidative Stress Defense Pathways in Rat Alveolar Type II Pneumocytes

    Directory of Open Access Journals (Sweden)

    Alexis Valauri-Orton

    2015-01-01

    Full Text Available Dichloroacetate (DCA is a water purification byproduct that is known to be hepatotoxic and hepatocarcinogenic and to induce peripheral neuropathy and damage macrophages. This study characterizes the effects of the haloacetate on lung cells by exposing rat alveolar type II (L2 cells to 0–24 mM DCA for 6–24 hours. Increasing DCA concentration and the combination of increasing DCA concentration plus longer exposures decrease measures of cellular health. Length of exposure has no effect on oxidative stress biomarkers, glutathione, SOD, or CAT. Increasing DCA concentration alone does not affect total glutathione or its redox ratio but does increase activity in the SOD/CAT oxidative stress defense pathway. These data suggest that alveolar type II cells rely on SOD and CAT more than glutathione to combat DCA-induced stress.

  20. Diffusible Factors Secreted by Glioblastoma and Medulloblastoma Cells Induce Oxidative Stress in Bystander Neural Stem Progenitors.

    Science.gov (United States)

    Sharma, Neha; Colangelo, Nicholas W; de Toledo, Sonia M; Azzam, Edouard I

    2016-08-01

    Harmful effects that alter the homeostasis of neural stem or progenitor cells (NSPs) can affect regenerative processes in the central nervous system. We investigated the effect of soluble factors secreted by control or (137)Cs-γ-irradiated glioblastoma or medulloblastoma cells on redox-modulated endpoints in recipient human NSPs. Growth medium harvested from the nonirradiated brain tumor cells, following 24 h of growth, induced prominent oxidative stress in recipient NSPs as judged by overall increases in mitochondrial superoxide radical levels (p p21(Waf1) and p27(Kip1), and perturbations in cell cycle progression (p cells to radiation only slightly altered the induced oxidative changes in the bystander NSPs, except for medium from irradiated medulloblastoma cells that was more potent at inducing apoptosis in the NSPs than medium from nonirradiated cells (p cells is often used to support the growth of stem cells.

  1. Mechanism of oxidative stress involved in the toxicity of ZnO nanoparticles against eukaryotic cells

    Directory of Open Access Journals (Sweden)

    M. Saliani

    2016-01-01

    Full Text Available ZnO NPs (zinc oxide nanoparticles has generated significant scientific interest as a novel antibacterial and anticancer agent. Since oxidative stress is a critical determinant of ZnO NPs-induced damage, it is necessary to characterize their underlying mode of action. Different structural and physicochemical properties of ZnO NPs such as particle surface, size, shape, crystal structure, chemical position, and presence of metals can lead to changes in biological activities including ROS (reactive oxygen species production. However, there are some inconsistencies in the literature on the relation between the physicochemical features of ZnO NPs and their plausible oxidative stress mechanism. Herein, the possible oxidative stress mechanism of ZnO NPs was reviewed. This is worthy of further detailed evaluations in order to improve our understanding of vital NPs characteristics governing their toxicity. Therefore, this study focuses on the different reported oxidative stress paradigms induced by ZnO NPs including ROS generated by NPs, oxidative stress due to the NPs-cell interaction, and role of the particle dissolution in the oxidative damage. Also, this study tries to characterize and understand the multiple pathways involved in oxidative stress induced by ZnO NPs. Knowledge about different cellular signaling cascades stimulated by ZnO NPs lead to the better interpretation of the toxic influences induced by the cellular and acellular parameters. Regarding the potential benefits of toxic effects of ZnO NPs, in-depth evaluation of their toxicity mechanism and various effects of these nanoparticles would facilitate their implementation for biomedical applications.

  2. Hypothermia enhances bcl-2 expression and protects against oxidative stress-induced cell death in Chinese hamster ovary cells.

    Science.gov (United States)

    Slikker, W; Desai, V G; Duhart, H; Feuers, R; Imam, S Z

    2001-08-01

    Oxidative stress is one of the major causes of cellular injury. Various reactive oxygen (ROS) and nitrogen (RNS) species such as superoxide, hydroxyl radical, peroxynitrite, and nitric oxide are involved in the manifestations of different types of organ toxicity and the resultant syndromes, symptoms, or diseases. Hypothermic conditions have been reported to reduce the oxidative stress in various in vitro and in vivo studies. In the present study, we sought to determine the effect of lowered temperatures on oxidative stress-induced cell death in Chinese hamster ovary (CHO) cells. We also investigated the oxidative stress-induced alterations in the expression of anti-apoptotic protein, bcl-2, in CHO cells at lowered temperatures. CHO cells were incubated at four different temperatures of 30, 32, 35, and 37 degrees C (control temperature) from 1 to 4 d. In another set, the cells were incubated with 100 microM hydrogen peroxide (H(2)O(2)) for 30 min before harvesting at different time points. The cells were harvested at 1, 2, 3, and 4 d. Cell survival was significantly higher at 30 degrees C as compared to 37 degrees C over 4 d of incubation. In cells incubated with H(2)O(2), significantly higher cell viability was observed at lower temperatures as compared to the cells incubated at 37 degrees C. The activity of glutathione peroxidase (GSH-Px) also increased significantly at lower temperatures. Lowered temperature also provided a significant increase in the expression of anti-apoptotic protein, bcl-2 after 4 d of incubation. These data suggest that hypothermic conditions lowers the risk of oxidative stress-induced cellular damage and programmed cell death by increasing the activity of GSH-Px and by the induction in the expression of the anti-apoptotic protein, bcl-2.

  3. A Role of Fluoride on Free Radical Generation and Oxidative Stress in BV-2 Microglia Cells

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    Xi Shuhua

    2012-01-01

    Full Text Available The generation of ROS and lipid peroxidation has been considered to play an important role in the pathogenesis of chronic fluoride toxicity. In the present study, we observed that fluoride activated BV-2 microglia cell line by observing OX-42 expression in immunocytochemistry. Intracellular superoxide dismutase (SOD, glutathione (GSH, malondialdehyde (MDA, reactive oxygen species (ROS, superoxide anions (O2∙-, nitric oxide synthase (NOS, nitrotyrosine (NT and nitric oxide (NO, NOS in cell medium were determined for oxidative stress assessment. Our study found that NaF of concentration from 5 to 20 mg/L can stimuli BV-2 cells to change into activated microglia displaying upregulated OX-42 expression. SOD activities significantly decreased in fluoride-treated BV-2 cells as compared with control, and MDA concentrations and contents of ROS and O2∙- increased in NaF-treated cells. Activities of NOS in cells and medium significantly increased with fluoride concentrations in a dose-dependent manner. NT concentrations also increased significantly in 10 and 50 mg/L NaF-treated cells compared with the control cells. Our present study demonstrated that toxic effects of fluoride on the central nervous system possibly partly ascribed to activiting of microglia, which enhanced oxidative stress induced by ROS and reactive nitrogen species.

  4. A Numerical Investigation of the Thermal Stresses of a Planar Solid Oxide Fuel Cell

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    Paulina Pianko-Oprych

    2016-09-01

    Full Text Available A typical operating temperature of a solid oxide fuel cell (SOFC is quite high above 750 °C and affects the thermomechanical behavior of the cell. Thermal stresses may cause microstructural instability and sub-critical cracking. Therefore, a joint analysis by the computational fluid dynamics (CFD and computational structural mechanics based on the finite element method (FEM was carried out to analyze thermal stresses in a planar SOFC and to predict potential failure locations in the cell. A full numerical model was based on the coupling of thermo-fluid model with the thermo-mechanical model. Based on a temperature distribution from the thermo-fluid model, stress distribution including the von Mises stress, shear stress as well as the operating principal stress were derived in the thermo-mechanical model. The FEM calculations were performed under different working conditions of the planar SOFC. The highest total stress was noticed at the lower operating voltage of 0.3 V, while the lowest total stress was determined at the voltage of 0.7 V. The obtained stress distributions allowed a better understanding of details of internal processes occurring within the SOFC and provided helpful guidance in the optimization of a new SOFC design.

  5. Mitochondrial aldehyde dehydrogenase 2 protects gastric mucosa cells against DNA damage caused by oxidative stress.

    Science.gov (United States)

    Duan, Yantao; Gao, Yaohui; Zhang, Jun; Chen, Yinan; Jiang, Yannan; Ji, Jun; Zhang, Jianian; Chen, Xuehua; Yang, Qiumeng; Su, Liping; Zhang, Jun; Liu, Bingya; Zhu, Zhenggang; Wang, Lishun; Yu, Yingyan

    2016-04-01

    Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a member of the aldehyde dehydrogenase superfamily and is involved with the metabolic processing of aldehydes. ALDH2 plays a cytoprotective role by removing aldehydes produced during normal metabolism. We examined the cytoprotective role of ALDH2 specifically in gastric mucosa cells. Overexpression of ALDH2 increased the viability of gastric mucosa cells treated with H2O2, while knockdown of ALDH2 had an opposite effect. Moreover, overexpression of ALDH2 protected gastric mucosa cells against oxidative stress-induced apoptosis as determined by flow cytometry, Hoechst 33342, and TUNEL assays. Consistently, ALDH2 knockdown had an opposite effect. Additionally, DNA damage was ameliorated in ALDH2-overexpressing gastric mucosa cells treated with H2O2. We further identified that this cytoprotective role of ALDH2 was mediated by metabolism of 4-hydroxynonenal (4-HNE). Consistently, 4-HNE mimicked the oxidative stress induced by H2O2 in gastric mucosa cells. Treatment with 4-HNE increased levels of DNA damage in ALDH2-knockdown GES-1 cells, while overexpression of ALDH2 decreased 4-HNE-induced DNA damage. These findings suggest that ALDH2 can protect gastric mucosa cells against DNA damage caused by oxidative stress by reducing levels of 4-HNE.

  6. Chromatin remodeling regulates catalase expression during cancer cells adaptation to chronic oxidative stress.

    Science.gov (United States)

    Glorieux, Christophe; Sandoval, Juan Marcelo; Fattaccioli, Antoine; Dejeans, Nicolas; Garbe, James C; Dieu, Marc; Verrax, Julien; Renard, Patricia; Huang, Peng; Calderon, Pedro Buc

    2016-10-01

    Regulation of ROS metabolism plays a major role in cellular adaptation to oxidative stress in cancer cells, but the molecular mechanism that regulates catalase, a key antioxidant enzyme responsible for conversion of hydrogen peroxide to water and oxygen, remains to be elucidated. Therefore, we investigated the transcriptional regulatory mechanism controlling catalase expression in three human mammary cell lines: the normal mammary epithelial 250MK primary cells, the breast adenocarcinoma MCF-7 cells and an experimental model of MCF-7 cells resistant against oxidative stress resulting from chronic exposure to H2O2 (Resox), in which catalase was overexpressed. Here we identify a novel promoter region responsible for the regulation of catalase expression at -1518/-1226 locus and the key molecules that interact with this promoter and affect catalase transcription. We show that the AP-1 family member JunB and retinoic acid receptor alpha (RARα) mediate catalase transcriptional activation and repression, respectively, by controlling chromatin remodeling through a histone deacetylases-dependent mechanism. This regulatory mechanism plays an important role in redox adaptation to chronic exposure to H2O2 in breast cancer cells. Our study suggests that cancer adaptation to oxidative stress may be regulated by transcriptional factors through chromatin remodeling, and reveals a potential new mechanism to target cancer cells.

  7. Nanoparticle induced oxidative stress in cancer cells: adding new pieces to an incomplete jigsaw puzzle.

    Science.gov (United States)

    Nogueira, Daniele Rubert; Rolim, Clarice M Bueno; Farooqi, Ammad Ahmad

    2014-01-01

    Nanotechnology is an emerging field with many promising applications in drug delivery systems. Because of outstanding developments in this field, rapidly increasing research is directed to the development of nanocarriers that may enhance the availability of drugs to the target sites. Substantial fraction of information has been added into the existing scientific literature focusing on the fact that nanoparticles usually generate reactive oxygen species to a greater extent than micro-sized particles. It is worth mentioning that oxidative stress regulates an array of cell signaling cascades that resulted in cancer cell damage. Accumulating experimental evidence over the years has shown that wide-ranging biological mechanisms are triggered by these NPs in cultured cells due to the unique properties of engineered nanoparticles. In this review, we have attempted to provide an overview of the signaling cascades that are activated by oxidative stress in cancer cells in response to different kinds of nanomaterials, including quantum dots, metallic and polymeric nanoparticles.

  8. Dexamethasone-Induced Oxidative Stress Enhances Myeloma Cell Radiosensitization While Sparing Normal Bone Marrow Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Soumen Bera

    2010-12-01

    Full Text Available Dexamethasone (Dex and radiation therapy are established modalities in multiple myeloma. In this study, we propose a novel combination of Dex plus radiation that shows superior clonogenic cell killing and apoptosis of myeloma cells and selectively eliminates myeloma cells when cocultured with bone marrow stromal cells (BMSCs. Dex was found to inhibit the release of interleukin-6 from irradiated BMSCs, which is an established myeloma cell proproliferative cytokine. In 5TGM1 model, the combination of Dex with skeletal targeted radiotherapy (153-Sm-EDTMP prolonged median survival time and inhibited radiation-induced myelosuppression. A two-cycle treatment of Dex plus 153-Sm-EDTMP was well tolerated and further improved median survival time. Mechanistically, Dex increased superoxide and hydrogen peroxide production and augmented radiation-induced oxidative stress and cell death of myeloma cells. In contrast, Dex inhibited radiation-induced increase in pro-oxidant levels and enhanced the clonogenic survival in normal hematopoietic stem and progenitor cells. Treatment with either N-acetylcysteine or the combination of polyethylene glycol (PEG-conjugated copper, zinc-superoxide dismutase, and PEG-catalase significantly protected myeloma cells from Dex-induced clonogenic death. Overall, these results demonstrate that Dex in combination with radiotherapy enhances the killing of myeloma cells while protecting normal bone marrow hematopoiesis through a mechanism that involves selective increases in oxidative stress.

  9. Oxidative Stress in BPH

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    Murat Savas

    2009-01-01

    The present study has shown that there were not relationship between potency of oxidative stress and BPH. Further well designed studies should be planned to find out whether the oxidative stress-related parameters play role in BPH as an interesting pathology in regard of the etiopathogenesis. Keywords: benign prostatic hyperplasia, oxidative stress, prostate

  10. Mitochondria are targets for peroxisome-derived oxidative stress in cultured mammalian cells.

    Science.gov (United States)

    Wang, Bo; Van Veldhoven, Paul P; Brees, Chantal; Rubio, Noemí; Nordgren, Marcus; Apanasets, Oksana; Kunze, Markus; Baes, Myriam; Agostinis, Patrizia; Fransen, Marc

    2013-12-01

    Many cellular processes are driven by spatially and temporally regulated redox-dependent signaling events. Although mounting evidence indicates that organelles such as the endoplasmic reticulum and mitochondria can function as signaling platforms for oxidative stress-regulated pathways, little is known about the role of peroxisomes in these processes. In this study, we employ targeted variants of the genetically encoded photosensitizer KillerRed to gain a better insight into the interplay between peroxisomes and cellular oxidative stress. We show that the phototoxic effects of peroxisomal KillerRed induce mitochondria-mediated cell death and that this process can be counteracted by targeted overexpression of a select set of antioxidant enzymes, including peroxisomal glutathione S-transferase kappa 1, superoxide dismutase 1, and mitochondrial catalase. We also present evidence that peroxisomal disease cell lines deficient in plasmalogen biosynthesis or peroxisome assembly are more sensitive to KillerRed-induced oxidative stress than control cells. Collectively, these findings confirm and extend previous observations suggesting that disturbances in peroxisomal redox control and metabolism can sensitize cells to oxidative stress. In addition, they lend strong support to the ideas that peroxisomes and mitochondria share a redox-sensitive relationship and that the redox communication between these organelles is not only mediated by diffusion of reactive oxygen species from one compartment to the other. Finally, these findings indicate that mitochondria may act as dynamic receivers, integrators, and transmitters of peroxisome-derived mediators of oxidative stress, and this may have profound implications for our views on cellular aging and age-related diseases.

  11. The neuroprotective properties of palmitoylethanolamine against oxidative stress in a neuronal cell line

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    Chapman Kent D

    2009-12-01

    Full Text Available Abstract Background N-acylethanolamines (NAEs are lipids upregulated in response to cell and tissue injury and are involved in cytoprotection. Arachidonylethanolamide (AEA is a well characterized NAE that is an endogenous ligand at cannabinoid and vanilloid receptors, but it exists in small quantities relative to other NAE types. The abundance of other NAE species, such as palmitoylethanolamine (PEA, together with their largely unknown function and receptors, has prompted us to examine the neuroprotective properties and mechanism of action of PEA. We hypothesized that PEA protects HT22 cells from oxidative stress and activates neuroprotective kinase signaling pathways. Results Indeed PEA protected HT22 cells from oxidative stress in part by mediating an increase in phosphorylated Akt (pAkt and ERK1/2 immunoreactivity as well as pAkt nuclear translocation. These changes take place within a time frame consistent with neuroprotection. Furthermore, we determined that changes in pAkt immunoreactivity elicited by PEA were not mediated by activation of cannabinoid receptor type 2 (CB2, thus indicating a novel mechanism of action. These results establish a role for PEA as a neuroprotectant against oxidative stress, which occurs in a variety of neurodegenerative diseases. Conclusions The results from this study reveal that PEA protects HT22 cells from oxidative stress and alters the localization and expression levels of kinases known to be involved in neuroprotection by a novel mechanism. Overall, these results identify PEA as a neuroprotectant with potential as a possible therapeutic agent in neurodegenerative diseases involving oxidative stress.

  12. Oxidative Stress in Neurodegeneration

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    Varsha Shukla

    2011-01-01

    Full Text Available It has been demonstrated that oxidative stress has a ubiquitous role in neurodegenerative diseases. Major source of oxidative stress due to reactive oxygen species (ROS is related to mitochondria as an endogenous source. Although there is ample evidence from tissues of patients with neurodegenerative disorders of morphological, biochemical, and molecular abnormalities in mitochondria, it is still not very clear whether the oxidative stress itself contributes to the onset of neurodegeneration or it is part of the neurodegenerative process as secondary manifestation. This paper begins with an overview of how oxidative stress occurs, discussing various oxidants and antioxidants, and role of oxidative stress in diseases in general. It highlights the role of oxidative stress in neurodegenerative diseases like Alzheimer's, Parkinson's, and Huntington's diseases and amyotrophic lateral sclerosis. The last part of the paper describes the role of oxidative stress causing deregulation of cyclin-dependent kinase 5 (Cdk5 hyperactivity associated with neurodegeneration.

  13. The oxysterol 27-hydroxycholesterol increases β-amyloid and oxidative stress in retinal pigment epithelial cells

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    Dasari Bhanu

    2010-09-01

    Full Text Available Abstract Background Alzheimer's disease (AD and age-related macular degeneration (AMD share several pathological features including β-amyloid (Aβ peptide accumulation, oxidative damage, and cell death. The causes of AD and AMD are not known but several studies suggest disturbances in cholesterol metabolism as a culprit of these diseases. We have recently shown that the cholesterol oxidation metabolite 27-hydroxycholesterol (27-OHC causes AD-like pathology in human neuroblastoma SH-SY5Y cells and in organotypic hippocampal slices. However, the extent to which and the mechanisms by which 27-OHC may also cause pathological hallmarks related to AMD are ill-defined. In this study, the effects of 27-OHC on AMD-related pathology were determined in ARPE-19 cells. These cells have structural and functional properties relevant to retinal pigmented epithelial cells, a target in the course of AMD. Methods ARPE-19 cells were treated with 0, 10 or 25 μM 27-OHC for 24 hours. Levels of Aβ peptide, mitochondrial and endoplasmic reticulum (ER stress markers, Ca2+ homeostasis, glutathione depletion, reactive oxygen species (ROS generation, inflammation and cell death were assessed using ELISA, Western blot, immunocytochemistry, and specific assays. Results 27-OHC dose-dependently increased Aβ peptide production, increased levels of ER stress specific markers caspase 12 and gadd153 (also called CHOP, reduced mitochondrial membrane potential, triggered Ca2+ dyshomeostasis, increased levels of the nuclear factor κB (NFκB and heme-oxygenase 1 (HO-1, two proteins activated by oxidative stress. Additionally, 27-OHC caused glutathione depletion, ROS generation, inflammation and apoptotic-mediated cell death. Conclusions The cholesterol metabolite 27-OHC is toxic to RPE cells. The deleterious effects of this oxysterol ranged from Aβ accumulation to oxidative cell damage. Our results suggest that high levels of 27-OHC may represent a common pathogenic factor for

  14. Cadmium induced oxidative stress in kidney epithelia cells

    DEFF Research Database (Denmark)

    Bjerregaard, Henning F.

    2007-01-01

    Cadmium (Cd) is an important industrial and environmental pollutant. In humans exposed to Cd via oral and/or pulmonary routes, the kidney is by far the primary organ affected adversely by Cd. It have been estimated that 7% of the human population may develop renal dysfunction from Cd exposure....... To minimize DCF photo-oxidation, illumination was limited to 100 ms exposures at 30 s intervals. ROS production rate was determined by linear regression analysis of change in the fluorescence intensity (FI) and expressed as increase in fluorescence intensity units (FIU) per min.    In order to evaluate...

  15. Oxidative stress mediated apoptosis induced by nickel ferrite nanoparticles in cultured A549 cells.

    Science.gov (United States)

    Ahamed, Maqusood; Akhtar, Mohd Javed; Siddiqui, Maqsood A; Ahmad, Javed; Musarrat, Javed; Al-Khedhairy, Abdulaziz A; AlSalhi, Mohamad S; Alrokayan, Salman A

    2011-05-10

    Due to the interesting magnetic and electrical properties with good chemical and thermal stabilities, nickel ferrite nanoparticles are being utilized in many applications including magnetic resonance imaging, drug delivery and hyperthermia. Recent studies have shown that nickel ferrite nanoparticles produce cytotoxicity in mammalian cells. However, there is very limited information concerning the toxicity of nickel ferrite nanoparticles at the cellular and molecular level. The aim of this study was to investigate the cytotoxicity, oxidative stress and apoptosis induction by well-characterized nickel ferrite nanoparticles (size 26 nm) in human lung epithelial (A549) cells. Nickel ferrite nanoparticles induced dose-dependent cytotoxicity in A549 cells demonstrated by MTT, NRU and LDH assays. Nickel ferrite nanoparticles were also found to induce oxidative stress evidenced by generation of reactive oxygen species (ROS) and depletion of antioxidant glutathione (GSH). Further, co-treatment with the antioxidant L-ascorbic acid mitigated the ROS generation and GSH depletion due to nickel ferrite nanoparticles suggesting the potential mechanism of oxidative stress. Quantitative real-time PCR analysis demonstrated that following the exposure of A549 cells to nickel ferrite nanoparticles, the level of mRNA expressions of cell cycle checkpoint protein p53 and apoptotic proteins (bax, caspase-3 and caspase-9) were significantly up-regulated, whereas the expression of anti-apoptotic proteins (survivin and bcl-2) were down-regulated. Moreover, activities of caspase-3 and caspase-9 enzymes were also significantly higher in nickel ferrite nanoparticles exposed cells. To the best of our knowledge this is the first report showing that nickel ferrite nanoparticles induced apoptosis in A549 cells through ROS generation and oxidative stress via p53, survivin, bax/bcl-2 and caspase pathways.

  16. Protective effect of alpha-mangostin against oxidative stress induced-retinal cell death

    Science.gov (United States)

    Fang, Yuan; Su, Tu; Qiu, Xiaorong; Mao, Pingan; Xu, Yidan; Hu, Zizhong; Zhang, Yi; Zheng, Xinhua; Xie, Ping; Liu, Qinghuai

    2016-01-01

    It is known that oxidative stress plays a pivotal role in age-related macular degeneration (AMD) pathogenesis. Alpha-mangostin is the main xanthone purified from mangosteen known as anti-oxidative properties. The aim of the study was to test the protective effect of alpha-mangostin against oxidative stress both in retina of light-damaged mice model and in hydrogen peroxide (H2O2)-stressed RPE cells. We observed that alpha-mangostin significantly inhibited light-induced degeneration of photoreceptors and 200 μM H2O2-induced apoptosis of RPE cells. 200 μM H2O2-induced generation of reactive oxygen species (ROS) and light-induced generation of malondialdehyde (MDA) were suppressed by alpha-mangostin. Alpha-mangostin stimulation resulted in an increase of superoxide dismutase (SOD) activity, glutathione peroxidase (GPX) activity and glutathione (GSH) content both in vivo and vitro. Furthermore, the mechanism of retinal protection against oxidative stress by alpha-mangostin involves accumulation and the nuclear translocation of the NF-E2-related factor (Nrf2) along with up-regulation the expression of heme oxygenas-1 (HO-1). Meanwhile, alpha-mangostin can activate the expression of PKC-δ and down-regulate the expression of mitogen-activated protein kinases (MAPKs), including ERK1/2, JNK, P38. The results suggest that alpha-mangostin could be a new approach to suspend the onset and development of AMD. PMID:26888416

  17. Preconditioning L6 Muscle Cells with Naringin Ameliorates Oxidative Stress and Increases Glucose Uptake.

    Directory of Open Access Journals (Sweden)

    R Dhanya

    Full Text Available Enhanced oxidative stress contributes to pathological changes in diabetes and its complications. Thus, strategies to reduce oxidative stress may alleviate these pathogenic processes. Herein, we have investigated Naringin mediated regulation of glutathione (GSH & intracellular free radical levels and modulation of glucose uptake under oxidative stress in L6 cell lines. The results from the study demonstrated a marked decrease in glutathione with a subsequent increase in free radical levels, which was reversed by the pretreatment of Naringin. We also observed that the increased malondialdehyde level, the marker of lipid peroxidation on induction of oxidative stress was retrieved on Naringin pretreatment. Addition of Naringin (100 μM showed approximately 40% reduction in protein glycation in vitro. Furthermore, we observed a twofold increase in uptake of fluorescent labeled glucose namely 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-ylAmino-2-Deoxyglucose (2-NBDG on Naringin treatment in differentiated L6 myoblast. The increased uptake of 2-NBDG by L6 myotubes may be attributed due to the enhanced translocation of GLUT4. Our results demonstrate that Naringin activate GSH synthesis through a novel antioxidant defense mechanism against excessive Reactive Oxygen Species (ROS production, contributing to the prevention of oxidative damage in addition to its effect on glycemic control.

  18. Preconditioning L6 Muscle Cells with Naringin Ameliorates Oxidative Stress and Increases Glucose Uptake.

    Science.gov (United States)

    Dhanya, R; Arun, K B; Nisha, V M; Syama, H P; Nisha, P; Santhosh Kumar, T R; Jayamurthy, P

    2015-01-01

    Enhanced oxidative stress contributes to pathological changes in diabetes and its complications. Thus, strategies to reduce oxidative stress may alleviate these pathogenic processes. Herein, we have investigated Naringin mediated regulation of glutathione (GSH) & intracellular free radical levels and modulation of glucose uptake under oxidative stress in L6 cell lines. The results from the study demonstrated a marked decrease in glutathione with a subsequent increase in free radical levels, which was reversed by the pretreatment of Naringin. We also observed that the increased malondialdehyde level, the marker of lipid peroxidation on induction of oxidative stress was retrieved on Naringin pretreatment. Addition of Naringin (100 μM) showed approximately 40% reduction in protein glycation in vitro. Furthermore, we observed a twofold increase in uptake of fluorescent labeled glucose namely 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)Amino)-2-Deoxyglucose (2-NBDG) on Naringin treatment in differentiated L6 myoblast. The increased uptake of 2-NBDG by L6 myotubes may be attributed due to the enhanced translocation of GLUT4. Our results demonstrate that Naringin activate GSH synthesis through a novel antioxidant defense mechanism against excessive Reactive Oxygen Species (ROS) production, contributing to the prevention of oxidative damage in addition to its effect on glycemic control.

  19. Effect of Nɛ-carboxymethyllysine on oxidative stress and the glutathione system in beta cells

    Directory of Open Access Journals (Sweden)

    Daniëlle M.P.H.J. Boesten

    2014-01-01

    Full Text Available One of the pathways involved in the pathogenesis of diabetic complications is the formation of excessive levels of advanced glycation end (AGE products. Nɛ-carboxymethyllysine (CML is one of the best-characterized AGEs. Because little is known about the effects of AGEs on pancreatic beta cells, we investigated the effect of CML on human pancreatic cells and determined the activity and gene expression of glutathione system components. CML at a concentration of 0.5 mM induced cell death in human pancreatic beta cells, which was accompanied by increased intracellular oxidative stress. No changes in the gene expression of the receptor for AGEs (RAGE were found, although an increase in the level of a target cytokine of RAGE after CML exposure was observed. Additionally we found that CML lowered the levels of GSH and affected the activity and expression of other components of the glutathione system. These changes indicate that the cells are even more vulnerable for oxidative stress after exposure to CML. Since beta cells are low in antioxidant enzymes and repair for oxidized DNA, CML, but most likely also other AGEs, accelerates beta cell dysfunction and increases beta cell death during chronic hyperglycemia.

  20. The Plant Hormone Cytokinin Confers Protection against Oxidative Stress in Mammalian Cells

    Science.gov (United States)

    Awad, Eman; Stopper, Helga

    2016-01-01

    Modulating key dynamics of plant growth and development, the effects of the plant hormone cytokinin on animal cells gained much attention recently. Most previous studies on cytokinin effects on mammalian cells have been conducted with elevated cytokinin concentration (in the μM range). However, to examine physiologically relevant dose effects of cytokinins on animal cells, we systematically analyzed the impact of kinetin in cultured cells at low and high concentrations (1nM-10μM) and examined cytotoxic and genotoxic conditions. We furthermore measured the intrinsic antioxidant activity of kinetin in a cell-free system using the Ferric Reducing Antioxidant Power assay and in cells using the dihydroethidium staining method. Monitoring viability, we looked at kinetin effects in mammalian cells such as HL60 cells, HaCaT human keratinocyte cells, NRK rat epithelial kidney cells and human peripheral lymphocytes. Kinetin manifests no antioxidant activity in the cell free system and high doses of kinetin (500 nM and higher) reduce cell viability and mediate DNA damage in vitro. In contrast, low doses (concentrations up to 100 nM) of kinetin confer protection in cells against oxidative stress. Moreover, our results show that pretreatment of the cells with kinetin significantly reduces 4-nitroquinoline 1-oxide mediated reactive oxygen species production. Also, pretreatment with kinetin retains cellular GSH levels when they are also treated with the GSH-depleting agent patulin. Our results explicitly show that low kinetin doses reduce apoptosis and protect cells from oxidative stress mediated cell death. Future studies on the interaction between cytokinins and human cellular pathway targets will be intriguing. PMID:28005918

  1. Optical studies of oxidative stress in pulmonary artery endothelial cells

    Science.gov (United States)

    Ghanian, Zahra; Sepehr, Reyhaneh; Eis, Annie; Kondouri, Ganesh; Ranji, Mahsa

    2015-03-01

    Reactive oxygen species (ROS) play an essential role in facilitating signal transduction processes within the cell and modulating the injuries. However, the generation of ROS is tightly controlled both spatially and temporally within the cell, making the study of ROS dynamics particularly difficult. This study present a novel protocol to quantify the dynamic of the mitochondrial superoxide as a precursor of reactive oxygen species. To regulate the mitochondrial superoxide level, metabolic perturbation was induced by administration of potassium cyanide (KCN). The presented method was able to monitor and measure the superoxide production rate over time. Our results demonstrated that the metabolic inhibitor, potassium cyanide (KCN) induced a significant increase in the rate of superoxide production in mitochondria of fetal pulmonary artery endothelial cells (FPAEC). Presented method sets the stage to study different ROS mediated injuries in vitro.

  2. Tat-HSP22 inhibits oxidative stress-induced hippocampal neuronal cell death by regulation of the mitochondrial pathway.

    Science.gov (United States)

    Jo, Hyo Sang; Kim, Dae Won; Shin, Min Jea; Cho, Su Bin; Park, Jung Hwan; Lee, Chi Hern; Yeo, Eun Ji; Choi, Yeon Joo; Yeo, Hyeon Ji; Sohn, Eun Jeong; Son, Ora; Cho, Sung-Woo; Kim, Duk-Soo; Yu, Yeon Hee; Lee, Keun Wook; Park, Jinseu; Eum, Won Sik; Choi, Soo Young

    2017-01-04

    Oxidative stress plays an important role in the progression of various neuronal diseases including ischemia. Heat shock protein 22 (HSP22) is known to protect cells against oxidative stress. However, the protective effects and mechanisms of HSP22 in hippocampal neuronal cells under oxidative stress remain unknown. In this study, we determined whether HSP22 protects against hydrogen peroxide (H2O2)-induced oxidative stress in HT-22 using Tat-HSP22 fusion protein. We found that Tat-HSP22 transduced into HT-22 cells and that H2O2-induced cell death, oxidative stress, and DNA damage were significantly reduced by Tat-HSP22. In addition, Tat-HSP22 markedly inhibited H2O2-induced mitochondrial membrane potential, cytochrome c release, cleaved caspase-3, and Bax expression levels, while Bcl-2 expression levels were increased in HT-22 cells. Further, we showed that Tat-HSP22 transduced into animal brain and inhibited cleaved-caspase-3 expression levels as well as significantly inhibited hippocampal neuronal cell death in the CA1 region of animals in the ischemic animal model. In the present study, we demonstrated that transduced Tat-HSP22 attenuates oxidative stress-induced hippocampal neuronal cell death through the mitochondrial signaling pathway and plays a crucial role in inhibiting neuronal cell death, suggesting that Tat-HSP22 protein may be used to prevent oxidative stress-related brain diseases including ischemia.

  3. Gamma-Glutamylcysteine Inhibits Oxidative Stress in Human Endothelial Cells

    Science.gov (United States)

    2012-01-01

    GGC treatment and pooled. Then, cells were suspended and lysed with hypotonic buffer and 10% (w/v) Nonidet P - 40 . After spinning, the cell pellet was...correlation with PPARγ DNA binding levels (pb0.05) and positive correlation trends with NF-κB p65 DNA binding ( p =0.059), 8-epi- PGF2α, ( p =0.080), and...TBARS ( p =0.129) levels through Pearson’s correlations. GSH synthetase (GSS) expression We found statistically lower GSS protein levels (0.93 to 0.85

  4. The influence of calreticulin on oxidative stress i n MCF-7 cells

    Directory of Open Access Journals (Sweden)

    Sree Jaya S

    2014-09-01

    Full Text Available Calreticulin (CRT, a multifunctional protein that regulates varied important cell functions, in addition CRT recently drawn notice that the function of oxidative stress induced apoptosis. At this point, the role of CRT through oxidative stress mediated apoptotic cell death is focused. Herein, we used mammary gland adenocarcinoma cell cells (MCF-7 in vitroto investigate the role CRT overexpression in cell death by promoting ROS induced apoptosis. Human CRT gene was isolated from blood, cDNA was synthesized, CRT was cloned to the XhoI/EcoRI restriction sites of a mammalian expression vector pcDNA 3.1 and plasmid was transfected in to MCF-7 cell line to promote apoptosis. After 24 h and 48 h transfection, cell proliferation, LDH leakage, lipid peroxidation, total protein, and glutathione concentrations were measured. CRT transfected cells expressed higher concentrations of lipid peroxidation and LDHleakage than control MCF -7 cells. There was a significant negative correlation between lipid peroxidation and cell proliferation. Glutathione did not appear to be a significant factor. Therefore, stimulation of CRT may modulate the growth inhibitory effects in human breast cancer cells. One mechanism of growth inhibition may be through increased lipid peroxidation.

  5. Bmi1 confers resistance to oxidative stress on hematopoietic stem cells.

    Directory of Open Access Journals (Sweden)

    Shunsuke Nakamura

    Full Text Available BACKGROUND: The polycomb-group (PcG proteins function as general regulators of stem cells. We previously reported that retrovirus-mediated overexpression of Bmi1, a gene encoding a core component of polycomb repressive complex (PRC 1, maintained self-renewing hematopoietic stem cells (HSCs during long-term culture. However, the effects of overexpression of Bmi1 on HSCs in vivo remained to be precisely addressed. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we generated a mouse line where Bmi1 can be conditionally overexpressed under the control of the endogenous Rosa26 promoter in a hematopoietic cell-specific fashion (Tie2-Cre;R26Stop(FLBmi1. Although overexpression of Bmi1 did not significantly affect steady state hematopoiesis, it promoted expansion of functional HSCs during ex vivo culture and efficiently protected HSCs against loss of self-renewal capacity during serial transplantation. Overexpression of Bmi1 had no effect on DNA damage response triggered by ionizing radiation. In contrast, Tie2-Cre;R26Stop(FLBmi1 HSCs under oxidative stress maintained a multipotent state and generally tolerated oxidative stress better than the control. Unexpectedly, overexpression of Bmi1 had no impact on the level of intracellular reactive oxygen species (ROS. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that overexpression of Bmi1 confers resistance to stresses, particularly oxidative stress, onto HSCs. This thereby enhances their regenerative capacity and suggests that Bmi1 is located downstream of ROS signaling and negatively regulated by it.

  6. Stanniocalcin 2 enhances mesenchymal stem cell survival by suppressing oxidative stress.

    Science.gov (United States)

    Kim, Pyung-Hwan; Na, Sang-Su; Lee, Bomnaerin; Kim, Joo-Hyun; Cho, Je-Yoel

    2015-12-01

    To overcome the disadvantages of stem cell-based cell therapy like low cell survival at the disease site, we used stanniocalcin 2 (STC2), a family of secreted glycoprotein hormones that function to inhibit apoptosis and oxidative damage and to induce proliferation. STC2 gene was transfected into two kinds of stem cells to prolong cell survival and protect the cells from the damage by oxidative stress. The stem cells expressing STC2 exhibited increased cell viability and improved cell survival as well as elevated expression of the pluripotency and self-renewal markers (Oct4 and Nanog) under sub-lethal oxidative conditions. Up-regulation of CDK2 and CDK4 and down-regulation of cell cycle inhibitors p16 and p21 were observed after the delivery of STC2. Furthermore, STC2 transduction activated pAKT and pERK 1/2 signal pathways. Taken together, the STC2 can be used to enhance cell survival and maintain long-term stemness in therapeutic use of stem cells.

  7. BRCA1 and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Yong Weon Yi

    2014-04-01

    Full Text Available The breast cancer susceptibility gene 1 (BRCA1 has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1’s many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.

  8. Oxidative stress in plant cell culture: a role in production of beta-thujaplicin by Cupresssus lusitanica suspension culture.

    Science.gov (United States)

    Zhao, Jian; Fujita, Koki; Sakai, Kokki

    2005-06-05

    Oxidative stress is a common physiological stress that often challenges plants. Reactive oxygen species (ROS) are major factors in oxidative stress that significantly affect plant cell growth and secondary metabolism. Here we used beta-thujaplicin production by Cupressus lusitanica cell culture as an example to demonstrate the common occurrence of oxidative stress in cultivated plant cells and its effect on multiple aspects of cell culture process. C. lusitanica cells cultivated under Fe(2+) stress generate a significant level of ROS, and oxidative stress also occurs at late stages of C. lusitanica cell cultures under normal conditions. ROS production inhibited cell growth, induced lipid peroxidation and cell death, and enhanced ethylene and beta-thujaplicin production. It is demonstrated that Fe(2+) stress enhances ROS production via the Fenton reaction and promotes beta-thujaplicin production via ROS-induced lipid peroxidation that may activate cyclic oxylipin and ethylene pathways. Results further indicate that H(2)O(2) is a positive signal for beta-thujaplicin production, whereas superoxide anion radical (O(2) (- )) negatively affects beta-thujaplicin induction and strongly induces cell death. The study suggests that evaluating the oxidative stress and plant responses in a cell culture process is very necessary and important for understanding biochemical processes and for gaining the maximal productivity of target secondary metabolites.

  9. Mitochondria are required for ATM activation by extranuclear oxidative stress in cultured human hepatoblastoma cell line Hep G2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Akinori, E-mail: morita@tokushima-u.ac.jp [Department of Radiation Medicine, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Department of Radiological Science, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8509 (Japan); Tanimoto, Keiji; Murakami, Tomoki; Morinaga, Takeshi [Department of Radiation Medicine, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Hosoi, Yoshio, E-mail: hosoi@med.tohoku.ac.jp [Department of Radiation Medicine, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Department of Radiation Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575 (Japan)

    2014-01-24

    Highlights: • Oxidative ATM activation can occur in the absence of nuclear DNA damage response. • The oxidized Hep G2 cells were subjected to subcellular fractionation. • The obtained results suggest that the ATM activation occurs in mitochondria. • ATM failed to respond to oxidative stress in mitochondria-depleted Hep G2 cells. • Mitochondria are required for the oxidative activation of ATM. - Abstract: Ataxia–telangiectasia mutated (ATM) is a serine/threonine protein kinase that plays a central role in DNA damage response (DDR). A recent study reported that oxidized ATM can be active in the absence of DDR. However, the issue of where ATM is activated by oxidative stress remains unclear. Regarding the localization of ATM, two possible locations, namely, mitochondria and peroxisomes are possible. We report herein that ATM can be activated when exposed to hydrogen peroxide without inducing nuclear DDR in Hep G2 cells, and the oxidized cells could be subjected to subcellular fractionation. The first detergent-based fractionation experiment revealed that active, phosphorylated ATM was located in the second fraction, which also contained both mitochondria and peroxisomes. An alternative fractionation method involving homogenization and differential centrifugation, which permits the light membrane fraction containing peroxisomes to be produced, but not mitochondria, revealed that the light membrane fraction contained only traces of ATM. In contrast, the heavy membrane fraction, which mainly contained mitochondrial components, was enriched in ATM and active ATM, suggesting that the oxidative activation of ATM occurs in mitochondria and not in peroxisomes. In Rho 0-Hep G2 cells, which lack mitochondrial DNA and functional mitochondria, ATM failed to respond to hydrogen peroxide, indicating that mitochondria are required for the oxidative activation of ATM. These findings strongly suggest that ATM can be activated in response to oxidative stress in mitochondria

  10. Live-cell Imaging Approaches for the Investigation of Xenobiotic-Induced Oxidant Stress

    Science.gov (United States)

    BACKGROUND: Oxidant stress is arguably a universal feature in toxicology. Research studies on the role of oxidant stress induced by xenobiotic exposures have typically relied on the identification of damaged biomolecules using a variety of conventional biochemical and molecular t...

  11. Mitochondrial oxidative stress in aortic stiffening with age: the role of smooth muscle cell function.

    Science.gov (United States)

    OBJECTIVE: Age-related aortic stiffness is an independent risk factor for cardiovascular diseases. Although oxidative stress is implicated in aortic stiffness, the underlying molecular mechanisms remain unelucidated. Here, we examined the source of oxidative stress in aging and i...

  12. Airborne Fine Particulate Matter Induces Oxidative Stress and Inflammation in Human Nasal Epithelial Cells.

    Science.gov (United States)

    Hong, Zhicong; Guo, Zhiqiang; Zhang, Ruxin; Xu, Jian; Dong, Weiyang; Zhuang, Guoshun; Deng, Congrui

    2016-01-01

    Airborne fine particulate matter with an aerodynamic diameter equal to or smaller than 2.5 μm is abbreviated as PM2.5, which is one of the main components in air pollution. Exposure to PM2.5 is associated with increased risk of many human diseases, including chronic and allergic rhinitis, but the underlying molecular mechanism for its toxicity has not been fully elucidated. We have hypothesized that PM2.5 may cause oxidative stress and enhance inflammatory responses in nasal epithelial cells. Accordingly, we used human RPMI 2650 cells, derived from squamous cell carcinoma of the nasal septum, as a model of nasal epithelial cells, and exposed them to PM2.5 that was collected at Fudan University (31.3°N, 121.5°E) in Shanghai, China. PM2.5 exposure decreased the viability of RPMI 2650 cells, suggesting that PM2.5 may impair the barrier function of nasal epithelial cells. Moreover, PM2.5 increased the levels of intracellular reactive oxygen species (ROS) and the nuclear translocation of NF-E2-related factor-2 (Nrf2). Importantly, PM2.5 also decreased the activities of superoxide dismutase, catalase and glutathione peroxidase. Pretreatment with N-Acetyl-L-cysteine (an anti-oxidant) reduced the degree of the PM2.5-induced oxidative stress in RPMI 2650 cells. In addition, PM2.5 increased the production of granulocyte-macrophage colony-stimulating factor, tumor necrosis factor-α, interleukin-13 and eotaxin (C-C motif chemokine ligand 11), each of which initiates and/or augments local inflammation. These results suggest that PM2.5 may induce oxidative stress and inflammatory responses in human nasal epithelial cells, thereby leading to nasal inflammatory diseases. The present study provides insights into cellular injury induced by PM2.5.

  13. Protection of human HepG2 cells against oxidative stress by the flavonoid epicatechin.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Izquierdo-Pulido, María; Bravo, Laura; Goya, Luis

    2010-04-01

    Flavanols, such as epicatechin (EC), constitute an important part of the human diet; they can be found in green tea, grapes and cocoa and possess different biological activities such as antioxidant, anti-inflammatory and anticarcinogenic. This study investigated the potential chemo-protective effect of EC against oxidative stress induced by tert-butylhydroperoxide (t-BOOH) on human HepG2 cells. Cell viability by lactate dehydrogenase assay and markers of oxidative status: reduced glutathione (GSH), malondialdehyde (MDA), reactive oxygen species (ROS), glutathione peroxidase (GPx) and glutathione reductase (GR) were evaluated. Pretreatment of cells with EC for 20 h prevented the enhanced cell damage and GPx and GR activities as well as the decrease in GSH induced by t-BOOH. The increased ROS generation induced by t-BOOH was also partly prevented by a pretreatment for 20 h with EC. In addition, pretreatment of cells with EC for 20 h recovered the t-BOOH-induced MDA concentration to control values. A pretreatment for 2 h with EC did not reduce cell damage but partly recovered GSH, reduced ROS levels and muffled the increase of GPx and GR after exposure to t-BOOH. Treatment of HepG2 cells with concentrations of EC in the micromolar range confers a significant protection against oxidative stress.

  14. Telomere dynamics in human mesenchymal stem cells after exposure to acute oxidative stress

    DEFF Research Database (Denmark)

    Harbo, M.; Koelvraa, S.; Serakinci, N.;

    2012-01-01

    A gradual shortening of telomeres due to replication can be measured using the standard telomere restriction fragments (TRF) assay and other methods by measuring the mean length of all the telomeres in a cell. In contrast, stress-induced telomere shortening, which is believed to be just...... as important for causing cellular senescence, cannot be measured properly using these methods. Stress-induced telomere shortening caused by, e.g. oxidative damage happens in a stochastic manner leaving just a few single telomeres critically short. It is now possible to visualize these few ultra-short telomeres...... due to the advantages of the newly developed Universal single telomere length assay (STELA), and we therefore believe that this method should be considered the method of choice when measuring the length of telomeres after exposure to oxidative stress. In order to test our hypothesis, cultured human...

  15. Albumin-bound fatty acids induce mitochondrial oxidant stress and impair antioxidant responses in proximal tubular cells

    NARCIS (Netherlands)

    Ishola, D. A.; Post, J. A.; van Timmeren, M. M.; Bakker, S. J. L.; Goldschmeding, R.; Koomans, H. A.; Braam, B.; Joles, J. A.

    2006-01-01

    Albumin induces oxidative stress and cytokine production in proximal tubular cells (PTECs). Albumin-bound fatty acids (FAs) enhance tubulopathic effects of albumin in vivo. We proposed that FA aggravation of albumin-induced oxidative stress in PTECs might be involved. We hypothesized that mitochondr

  16. Oxidative stress enhances Axl-mediated cell migration through an Akt1/Rac1-dependent mechanism.

    Science.gov (United States)

    Huang, Jhy-Shrian; Cho, Chun-Yu; Hong, Chih-Chen; Yan, Ming-De; Hsieh, Mao-Chih; Lay, Jong-Ding; Lai, Gi-Ming; Cheng, Ann-Lii; Chuang, Shuang-En

    2013-12-01

    Persistent oxidative stress is common in cancer cells because of abnormal generation of reactive oxygen species (ROS) and has been associated with malignant phenotypes, such as chemotherapy resistance and metastasis. Both overexpression of Axl and abnormal ROS elevation have been linked to cell transformation and increased cell migration. However, the relationship between Axl and ROS in malignant cell migration has not been previously evaluated. Using an in vitro human lung cancer model, we examined the redox state of lung adenocarcinoma cell lines of low metastatic (CL1-0) and high metastatic (CL1-5) potentials. Here we report that Axl activation elicits ROS accumulation through the oxidase-coupled small GTPase Rac1. We also observed that oxidative stress could activate Axl phosphorylation to synergistically enhance cell migration. Further, Axl signaling activated by H2O2 treatment results in enhancement of cell migration via a PI3K/Akt-dependent pathway. The kinase activity of Axl is required for the Axl-mediated cell migration and prolongs the half-life of phospho-Akt under oxidative stress. Finally, downregulation of Akt1, but not Akt2, by RNAi in Axl-overexpressing cells inhibits the amount of activated Rac1 and the ability to migrate induced by H2O2 treatment. Together, these results show that a novel Axl-signaling cascade induced by H2O2 treatment triggers cell migration through the PI3K/Akt1/Rac1 pathway. Elucidation of redox regulation in Axl-related malignant migration may provide new molecular insights into the mechanisms underlying tumor progression.

  17. Oxidative stress induces caveolin 1 degradation and impairs caveolae functions in skeletal muscle cells.

    Directory of Open Access Journals (Sweden)

    Alexis Mougeolle

    Full Text Available Increased level of oxidative stress, a major actor of cellular aging, impairs the regenerative capacity of skeletal muscle and leads to the reduction in the number and size of muscle fibers causing sarcopenia. Caveolin 1 is the major component of caveolae, small membrane invaginations involved in signaling and endocytic trafficking. Their role has recently expanded to mechanosensing and to the regulation of oxidative stress-induced pathways. Here, we increased the amount of reactive oxidative species in myoblasts by addition of hydrogen peroxide (H2O2 at non-toxic concentrations. The expression level of caveolin 1 was significantly decreased as early as 10 min after 500 μM H2O2 treatment. This reduction was not observed in the presence of a proteasome inhibitor, suggesting that caveolin 1 was rapidly degraded by the proteasome. In spite of caveolin 1 decrease, caveolae were still able to assemble at the plasma membrane. Their functions however were significantly perturbed by oxidative stress. Endocytosis of a ceramide analog monitored by flow cytometry was significantly diminished after H2O2 treatment, indicating that oxidative stress impaired its selective internalization via caveolae. The contribution of caveolae to the plasma membrane reservoir has been monitored after osmotic cell swelling. H2O2 treatment increased membrane fragility revealing that treated cells were more sensitive to an acute mechanical stress. Altogether, our results indicate that H2O2 decreased caveolin 1 expression and impaired caveolae functions. These data give new insights on age-related deficiencies in skeletal muscle.

  18. JNK and NADPH Oxidase Involved in Fluoride-Induced Oxidative Stress in BV-2 Microglia Cells

    Directory of Open Access Journals (Sweden)

    Ling Yan

    2013-01-01

    Full Text Available Excessive fluoride may cause central nervous system (CNS dysfunction, and oxidative stress is a recognized mode of action of fluoride toxicity. In CNS, activated microglial cells can release more reactive oxygen species (ROS, and NADPH oxidase (NOX is the major enzyme for the production of extracellular superoxide in microglia. ROS have been characterized as an important secondary messenger and modulator for various mammalian intracellular signaling pathways, including the MAPK pathways. In this study we examined ROS production and TNF-α, IL-1β inflammatory cytokines releasing, and the expression of MAPKs in BV-2 microglia cells treated with fluoride. We found that fluoride increased JNK phosphorylation level of BV-2 cells and pretreatment with JNK inhibitor SP600125 markedly reduced the levels of intracellular and NO. NOX inhibitor apocynin and iNOS inhibitor SMT dramatically decreased NaF-induced ROS and NO generations, respectively. Antioxidant melatonin (MEL resulted in a reduction in JNK phosphorylation in fluoride-stimulated BV-2 microglia. The results confirmed that NOX and iNOS played an important role in fluoride inducing oxidative stress and NO production and JNK took part in the oxidative stress induced by fluoride and meanwhile also could be activated by ROS in fluoride-treated BV-2 cells.

  19. Combinations of Ashwagandha leaf extracts protect brain-derived cells against oxidative stress and induce differentiation.

    Directory of Open Access Journals (Sweden)

    Navjot Shah

    Full Text Available Ashwagandha, a traditional Indian herb, has been known for its variety of therapeutic activities. We earlier demonstrated anticancer activities in the alcoholic and water extracts of the leaves that were mediated by activation of tumor suppressor functions and oxidative stress in cancer cells. Low doses of these extracts were shown to possess neuroprotective activities in vitro and in vivo assays.We used cultured glioblastoma and neuroblastoma cells to examine the effect of extracts (alcoholic and water as well as their bioactive components for neuroprotective activities against oxidative stress. Various biochemical and imaging assays on the marker proteins of glial and neuronal cells were performed along with their survival profiles in control, stressed and recovered conditions. We found that the extracts and one of the purified components, withanone, when used at a low dose, protected the glial and neuronal cells from oxidative as well as glutamate insult, and induced their differentiation per se. Furthermore, the combinations of extracts and active component were highly potent endorsing the therapeutic merit of the combinational approach.Ashwagandha leaf derived bioactive compounds have neuroprotective potential and may serve as supplement for brain health.

  20. Oxidative stress and myocarditis.

    Science.gov (United States)

    Tada, Yuko; Suzuki, Jun-Ichi

    2016-01-01

    Reactive oxygen species (ROS) such as superoxide anion and hydrogen peroxide are produced highly in myocarditis. ROS, which not only act as effectors for pathogen killing but also mediate signal transduction in the stress responsive pathways, are closely related with both innate and adaptive immunity. On the other hand, oxidative stress overwhelming the capacity of anti-oxidative system generated in severe inflammation has been suggested to damage tissues and exacerbate inflammation. Oxidative stress worsens the autoimmunological process of myocarditis, and suppression of the anti-oxidative system and long-lasting oxidative stress could be one of the pathological mechanisms of cardiac remodeling leading to inflammatory cardiomyopathy. Oxidative stress is considered to be one of the promising treatment targets of myocarditis. Evidences of anti-oxidative treatments in myocarditis have not been fully established. Basic strategies of anti-oxidative treatments include inhibition of ROS production, activation of anti-oxidative enzymes and elimination of generated free radicals. ROS are produced by mitochondrial respiratory chain reactions and enzymes including NADPH oxidases, cyclooxygenase, and xanthine oxidase. Other systems involved in inflammation and stress response, such as NF-κB, Nrf2/Keap1, and neurohumoral factors also influence oxidative stress in myocarditis. The efficacy of anti-oxidative treatments could also depend on the etiology and the phases of myocarditis. We review in this article the pathological significance of ROS and oxidative stress, and the potential anti-oxidative treatments in myocarditis.

  1. Oxidative stress plays a role in high glucose-induced activation of pancreatic stellate cells

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Gyeong Ryul; Lee, Esder; Chun, Hyun-Ji; Yoon, Kun-Ho; Ko, Seung-Hyun; Ahn, Yu-Bae; Song, Ki-Ho, E-mail: kihos@catholic.ac.kr

    2013-09-20

    Highlights: •High glucose increased production of reactive oxygen species in cultured pancreatic stellate cells. •High glucose facilitated the activation of these cells. •Antioxidant treatment attenuated high glucose-induced activation of these cells. -- Abstract: The activation of pancreatic stellate cells (PSCs) is thought to be a potential mechanism underlying islet fibrosis, which may contribute to progressive β-cell failure in type 2 diabetes. Recently, we demonstrated that antioxidants reduced islet fibrosis in an animal model of type 2 diabetes. However, there is no in vitro study demonstrating that high glucose itself can induce oxidative stress in PSCs. Thus, PSCs were isolated and cultured from Sprague Dawley rats, and treated with high glucose for 72 h. High glucose increased the production of reactive oxygen species. When treated with high glucose, freshly isolated PSCs exhibited myofibroblastic transformation. During early culture (passage 1), PSCs treated with high glucose contained an increased number of α-smooth muscle actin-positive cells. During late culture (passages 2–5), PSCs treated with high glucose exhibited increases in cell proliferation, the expression of fibronectin and connective tissue growth factor, release of interleukin-6, transforming growth factor-β and collagen, and cell migration. Finally, the treatment of PSCs with high glucose and antioxidants attenuated these changes. In conclusion, we demonstrated that high glucose increased oxidative stress in primary rat PSCs, thereby facilitating the activation of these cells, while antioxidant treatment attenuated high glucose-induced PSC activation.

  2. Elevated copper and oxidative stress in cancer cells as a target for cancer treatment.

    Science.gov (United States)

    Gupte, Anshul; Mumper, Russell J

    2009-02-01

    As we gain a better understanding of the factors affecting cancer etiology, we can design improved treatment strategies. Over the past three to four decades, there have been numerous successful efforts in recognizing important cellular proteins essential in cancer growth and therefore these proteins have been targeted for cancer treatment. However, studies have shown that targeting one or two proteins in the complex cancer cascade may not be sufficient in controlling and/or inhibiting cancer growth. Therefore, there is a need to examine features which are potentially involved in multiple facets of cancer development. In this review we discuss the targeting of the elevated copper (both in serum and tumor) and oxidative stress levels in cancer with the aid of a copper chelator d-penicillamine (d-pen) for potential cancer treatment. Numerous studies in the literature have reported that both the serum and tumor copper levels are elevated in a variety of malignancies, including both solid tumor and blood cancer. Further, the elevated copper levels have been shown to be directly correlated to cancer progression. Enhanced levels of intrinsic oxidative stress has been shown in variety of tumors, possibly due to the combination of factors such as elevated active metabolism, mitochondrial mutation, cytokines, and inflammation. The cancer cells under sustained ROS stress tend to heavily utilize adaptation mechanisms and may exhaust cellular ROS-buffering capacity. Therefore, the elevated copper levels and increased oxidative stress in cancer cells provide for a prospect of selective cancer treatment.

  3. Bcl-2 family members inhibit oxidative stress-induced programmed cell death in Saccharomyces cerevisiae.

    Science.gov (United States)

    Chen, Shao-Rong; Dunigan, David D; Dickman, Martin B

    2003-05-15

    Selected antiapoptotic genes were expressed in baker's yeast (Saccharomyces cerevisiae) to evaluate cytoprotective effects during oxidative stress. When exposed to treatments resulting in the generation of reactive oxygen species (ROS), including H(2)O(2), menadione, or heat shock, wild-type yeast died and exhibited apoptotic-like characteristics, consistent with previous studies. Yeast strains were generated expressing nematode ced-9, human bcl-2, or chicken bcl-xl genes. These transformants tolerated a range of oxidative stresses, did not display features associated with apoptosis, and remained viable under conditions that were lethal to wild-type yeast. Yeast strains expressing a mutant antiapoptotic gene (bcl-2 deltaalpha 5-6), known to be nonfunctional in mammalian cells, were unable to tolerate any of the ROS-generating insults. These data are the first report showing CED-9 has cytoprotective effects against oxidative stress, and add CED-9 to the list of Bcl-2 protein family members that modulate ROS-mediated programmed cell death. In addition, these data indicate that Bcl-2 family members protect wild-type yeast from physiological stresses. Taken together, these data support the concept of the broad evolutionary conservation and functional similarity of the apoptotic processes in eukaryotic organisms.

  4. Is Liver Enzyme Release Really Associated with Cell Necrosis Induced by Oxidant Stress?

    Science.gov (United States)

    Contreras-Zentella, Martha Lucinda; Hernández-Muñoz, Rolando

    2016-01-01

    Hepatic diseases are a major concern worldwide. Increased specific plasma enzyme activities are considered diagnostic features for liver diseases, since enzymes are released into the blood compartment following the deterioration of the organ. Release of liver mitochondrial enzymes is considered strong evidence for hepatic necrosis, which is associated with an increased production of ROS, often leading to greater hepatic lipid peroxidation. Lipotoxic mediators and intracellular signals activated Kupffer cells, which provides evidence strongly suggesting the participation of oxidant stress in acute liver damage, inducing the progression of liver injury to chronic liver damage. Elevated transaminase activities are considered as an index marker of hepatotoxicity, linked to oxidant stress. However, a drastic increase of serum activities of liver enzyme markers ought not necessarily to reflect liver cell death. In fact, increased serum levels of cytoplasmic enzymes have readily been observed after partial hepatectomy (PH) in the regenerating liver of rats. In this regard, we are now showing that in vitro modifications of the oxidant status affect differentially the release of liver enzymes, indicating that this release is a strictly controlled event and not directly related to the onset of oxidant stress of the liver.

  5. Is Liver Enzyme Release Really Associated with Cell Necrosis Induced by Oxidant Stress?

    Directory of Open Access Journals (Sweden)

    Martha Lucinda Contreras-Zentella

    2016-01-01

    Full Text Available Hepatic diseases are a major concern worldwide. Increased specific plasma enzyme activities are considered diagnostic features for liver diseases, since enzymes are released into the blood compartment following the deterioration of the organ. Release of liver mitochondrial enzymes is considered strong evidence for hepatic necrosis, which is associated with an increased production of ROS, often leading to greater hepatic lipid peroxidation. Lipotoxic mediators and intracellular signals activated Kupffer cells, which provides evidence strongly suggesting the participation of oxidant stress in acute liver damage, inducing the progression of liver injury to chronic liver damage. Elevated transaminase activities are considered as an index marker of hepatotoxicity, linked to oxidant stress. However, a drastic increase of serum activities of liver enzyme markers ought not necessarily to reflect liver cell death. In fact, increased serum levels of cytoplasmic enzymes have readily been observed after partial hepatectomy (PH in the regenerating liver of rats. In this regard, we are now showing that in vitro modifications of the oxidant status affect differentially the release of liver enzymes, indicating that this release is a strictly controlled event and not directly related to the onset of oxidant stress of the liver.

  6. Thioredoxin Binding Protein-2 Regulates Autophagy of Human Lens Epithelial Cells under Oxidative Stress via Inhibition of Akt Phosphorylation

    Science.gov (United States)

    Yao, Ke; Zhang, Yidong; Chen, Guangdi; Lai, Kairan; Yin, Houfa

    2016-01-01

    Oxidative stress plays an essential role in the development of age-related cataract. Thioredoxin binding protein-2 (TBP-2) is a negative regulator of thioredoxin (Trx), which deteriorates cellular antioxidant system. Our study focused on the autophagy-regulating effect of TBP-2 under oxidative stress in human lens epithelial cells (LECs). Human lens epithelial cells were used for cell culture and treatment. Lentiviral-based transfection system was used for overexpression of TBP-2. Cytotoxicity assay, western blot analysis, GFP/mCherry-fused LC3 plasmid, immunofluorescence, and transmission electronic microscopy were performed. The results showed that autophagic response of LECs with increased LC3-II, p62, and GFP/mCherry-LC3 puncta (P < 0.01) was induced by oxidative stress. Overexpression of TBP-2 further strengthens this response and worsens the cell viability (P < 0.01). Knockdown of TBP-2 attenuates the autophagic response and cell viability loss induced by oxidative stress. TBP-2 mainly regulates autophagy in the initiation stage, which is mTOR-independent and probably caused by the dephosphorylation of Akt under oxidative stress. These findings suggest a novel role of TBP-2 in human LECs under oxidative stress. Oxidative stress can cause cell injury and autophagy in LECs, and TBP-2 regulates this response. Hence, this study provides evidence regarding the role of TBP-2 in lens and the possible mechanism of cataract development. PMID:27656263

  7. Antioxidant effect of mogrosides against oxidative stress induced by palmitic acid in mouse insulinoma NIT-1 cells

    OpenAIRE

    Xu, Q.; Chen, S. Y.; Deng,L.D.; Feng, L.P.; Huang,L.Z.; R. R. Yu

    2013-01-01

    Excessive oxidative stress in pancreatic β cells, caused by glucose and fatty acids, is associated with the pathogenesis of type 2 diabetes. Mogrosides have shown antioxidant and antidiabetic activities in animal models of diabetes, but the underlying mechanisms remain unclear. This study evaluated the antioxidant effect of mogrosides on insulinoma cells under oxidative stress caused by palmitic acid, and investigated the underlying molecular mechanisms. Mouse insulinoma NIT-1 cells were cult...

  8. Antioxidant effect of mogrosides against oxidative stress induced by palmitic acid in mouse insulinoma NIT-1 cells

    OpenAIRE

    Xu, Q.; Chen, S. Y.; Deng,L.D.; Feng, L.P.; Huang,L.Z.; R. R. Yu

    2013-01-01

    Excessive oxidative stress in pancreatic β cells, caused by glucose and fatty acids, is associated with the pathogenesis of type 2 diabetes. Mogrosides have shown antioxidant and antidiabetic activities in animal models of diabetes, but the underlying mechanisms remain unclear. This study evaluated the antioxidant effect of mogrosides on insulinoma cells under oxidative stress caused by palmitic acid, and investigated the underlying molecular mechanisms. Mouse insulinoma NIT-1 cells were...

  9. Astaxanthin from Haematococcus pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity

    Science.gov (United States)

    Régnier, Philippe; Bastias, Jorge; Rodriguez-Ruiz, Violeta; Caballero-Casero, Noelia; Caballo, Carmen; Sicilia, Dolores; Fuentes, Axelle; Maire, Murielle; Crepin, Michel; Letourneur, Didier; Gueguen, Virginie; Rubio, Soledad; Pavon-Djavid, Graciela

    2015-01-01

    Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI)+)/ion trap-MS) characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC) assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 µM). No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 µM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases. PMID:25962124

  10. Astaxanthin from Haematococcus pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity

    Directory of Open Access Journals (Sweden)

    Philippe Régnier

    2015-05-01

    Full Text Available Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI+/ion trap-MS characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 µM. No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 µM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases.

  11. The influence of hydroxyurea on oxidative stress in sickle cell anemia

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    Lidiane de Souza Torres

    2012-01-01

    Full Text Available OBJECTIVE: The oxidative stress in 20 sickle cell anemia patients taking hydroxyurea and 13 sickle cell anemia patients who did not take hydroxyurea was compared with a control group of 96 individuals without any hemoglobinopathy. METHODS: Oxidative stress was assessed by thiobarbituric acid reactive species production, the Trolox-equivalent antioxidant capacity and plasma glutathione levels. RESULTS: Thiobarbituric acid reactive species values were higher in patients without specific medication, followed by patients taking hydroxyurea and the Control Group (p < 0.0001. The antioxidant capacity was higher in patients taking hydroxyurea and lower in the Control Group (p = 0.0002 for Trolox-equivalent antioxidant capacity and p < 0.0292 for plasma glutathione. Thiobarbituric acid reactive species levels were correlated with higher hemoglobin S levels (r = 0.55; p = 0.0040 and lower hemoglobin F concentrations(r = -0.52; p = 0.0067. On the other hand, plasma glutathione levels were negatively correlated with hemoglobin S levels (r = -0.49; p = 0.0111 and positively associated with hemoglobin F values (r = 0.56; p = 0.0031. CONCLUSION: Sickle cell anemia patients have high oxidative stress and, conversely, increased antioxidant activity. The increase in hemoglobin F levels provided by hydroxyurea and its antioxidant action may explain the reduction in lipid peroxidation and increased antioxidant defenses in these individuals.

  12. Astaxanthin from Haematococcus pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity.

    Science.gov (United States)

    Régnier, Philippe; Bastias, Jorge; Rodriguez-Ruiz, Violeta; Caballero-Casero, Noelia; Caballo, Carmen; Sicilia, Dolores; Fuentes, Axelle; Maire, Murielle; Crepin, Michel; Letourneur, Didier; Gueguen, Virginie; Rubio, Soledad; Pavon-Djavid, Graciela

    2015-05-07

    Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI)+)/ion trap-MS) characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC) assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 µM). No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 µM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases.

  13. The influence of hydroxyurea on oxidative stress in sickle cell anemia

    Science.gov (United States)

    Torres, Lidiane de Souza; da Silva, Danilo Grünig Humberto; Belini Junior, Edis; de Almeida, Eduardo Alves; Lobo, Clarisse Lopes de Castro; Cançado, Rodolfo Delfini; Ruiz, Milton Artur; Bonini-Domingos, Claudia Regina

    2012-01-01

    Objective The oxidative stress in 20 sickle cell anemia patients taking hydroxyurea and 13 sickle cell anemia patients who did not take hydroxyurea was compared with a control group of 96 individuals without any hemoglobinopathy. Methods Oxidative stress was assessed by thiobarbituric acid reactive species production, the Trolox-equivalent antioxidant capacity and plasma glutathione levels. Results Thiobarbituric acid reactive species values were higher in patients without specific medication, followed by patients taking hydroxyurea and the Control Group (p < 0.0001). The antioxidant capacity was higher in patients taking hydroxyurea and lower in the Control Group (p = 0.0002 for Trolox-equivalent antioxidant capacity and p < 0.0292 for plasma glutathione). Thiobarbituric acid reactive species levels were correlated with higher hemoglobin S levels (r = 0.55; p = 0.0040) and lower hemoglobin F concentrations(r = -0.52; p = 0.0067). On the other hand, plasma glutathione levels were negatively correlated with hemoglobin S levels (r = -0.49; p = 0.0111) and positively associated with hemoglobin F values (r = 0.56; p = 0.0031). Conclusion Sickle cell anemia patients have high oxidative stress and, conversely, increased antioxidant activity. The increase in hemoglobin F levels provided by hydroxyurea and its antioxidant action may explain the reduction in lipid peroxidation and increased antioxidant defenses in these individuals. PMID:23323065

  14. Low infra red laser light irradiation on cultured neural cells: effects on mitochondria and cell viability after oxidative stress

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    Giardino Luciana

    2009-04-01

    Full Text Available Abstract Background Considerable interest has been aroused in recent years by the well-known notion that biological systems are sensitive to visible light. With clinical applications of visible radiation in the far-red to near-infrared region of the spectrum in mind, we explored the effect of coherent red light irradiation with extremely low energy transfer on a neural cell line derived from rat pheochromocytoma. We focused on the effect of pulsed light laser irradiation vis-à-vis two distinct biological effects: neurite elongation under NGF stimulus on laminin-collagen substrate and cell viability during oxidative stress. Methods We used a 670 nm laser, with extremely low peak power output (3 mW/cm2 and at an extremely low dose (0.45 mJ/cm2. Neurite elongation was measured over three days in culture. The effect of coherent red light irradiation on cell reaction to oxidative stress was evaluated through live-recording of mitochondria membrane potential (MMP using JC1 vital dye and laser-confocal microscopy, in the absence (photo bleaching and in the presence (oxidative stress of H2O2, and by means of the MTT cell viability assay. Results We found that laser irradiation stimulates NGF-induced neurite elongation on a laminin-collagen coated substrate and protects PC12 cells against oxidative stress. Conclusion These data suggest that red light radiation protects the viability of cell culture in case of oxidative stress, as indicated by MMP measurement and MTT assay. It also stimulates neurite outgrowth, and this effect could also have positive implications for axonal protection.

  15. In vitro toxicity of nanosized copper particles in PC12 cells induced by oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Xu Pengjuan; Xu Jing; Liu Shichang [Nankai University, College of Medicine (China); Ren, Guogang [University of Hertfordshire, School of Aerospace Engineering (United Kingdom); Yang Zhuo, E-mail: zhuoyang@nankai.edu.cn [Nankai University, College of Medicine (China)

    2012-06-15

    Recent evidence suggests that some nanomaterials, which are widely used in many fields, have health effects. In order to investigate the cytotoxicity induced by nanosized copper particles (nano-Cu), PC12 cells, which were widely used as an in vitro model for the neuron research, were treated with different concentrations (0, 1, 10, 30, and 100 {mu}g/mL) of nano-Cu. The cell viability was determined by measurement of the reduction product of 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT). The oxidative stress induced by nano-Cu and its possible mechanism were studied in relation to the generation of reactive oxygen species (ROS) and the cellular activity of superoxide dismutase (SOD). Results showed that incubation of PC12 cells with increasing concentrations of nano-Cu induced a decrease of cell viability in a concentration- and time-dependent manner. In addition, flow cytometry assay using Annexin V-FITC/PI staining was used to investigate the mode of nano-Cu-induced cell death and quantified the percentage of apoptotic cells. Results showed that nano-Cu induced the significant apoptosis in PC12 cells. Meanwhile, intracellular accumulation of ROS was increased with the increased concentrations of nano-Cu and it was associated with decreased SOD activity, which was probably due to protect effects against the oxidative stress in PC12 cells. Results suggested that both excessive intracellular ROS and decreased SOD contributed to nano-Cu-induced cytotoxicity. In other words, the increasing of oxidative stress was a key mechanism in PC12 apoptosis induced by nano-Cu.

  16. Constituents of French Marigold (Tagetes patula L. Flowers Protect Jurkat T-Cells against Oxidative Stress

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    Irakli Chkhikvishvili

    2016-01-01

    Full Text Available The flowers of French marigold (Tagetes patula L. are widely used in folk medicine, in particular for treating inflammation-related disorders. However, cellular mechanisms of this activity demand further investigation. In the present work, we studied the potential of T. patula compounds to alleviate the oxidative stress in hydrogen peroxide-challenged human lymphoblastoid Jurkat T-cells. Crude extracts of marigold flowers and purified fractions containing flavonoids patuletin, quercetagetin, and quercetin and their derivatives, as well as the carotenoid lutein, were brought in contact with Jurkat cells challenged with 25 or 50 μM H2O2. Hydrogen peroxide caused oxidative stress in the cells, manifested as generation of superoxide and peroxyl radicals, reduced viability, arrested cell cycle, and enhanced apoptosis. The stress was alleviated by marigold ingredients that demonstrated high radical-scavenging capacity and enhanced the activity of antioxidant enzymes involved in neutralization of reactive oxygen species. Flavonoid fraction rich in quercetin and quercetagetin showed the highest cytoprotective activity, while patuletin in high dose exerted a cytotoxic effect associated with its anticancer potential. T. patula compounds enhanced the production of anti-inflammatory and antioxidant interleukin-10 (IL-10 in Jurkat cells. Both direct radical-scavenging capacity and stimulation of protective cellular mechanisms can underlay the anti-inflammatory properties of marigold flowers.

  17. Selenite induces apoptosis in sarcomatoid malignant mesothelioma cells through oxidative stress.

    Science.gov (United States)

    Nilsonne, Gustav; Sun, Xiaojuan; Nyström, Christina; Rundlöf, Anna-Klara; Potamitou Fernandes, Aristi; Björnstedt, Mikael; Dobra, Katalin

    2006-09-15

    Malignant mesothelioma cells differentiate into sarcomatoid or epithelioid phenotypes. The sarcomatoid cell type is more resistant to chemotherapy and gives a worse prognosis. We have investigated whether selenite alone and in combination with doxorubicin induced apoptosis in variously differentiated mesothelioma cells. Selenite in concentrations that could potentially be administered to patients strongly inhibited the growth of the sarcomatoid mesothelioma cells (IC50 = 7.5 microM), whereas epithelioid cells were more sensitive to doxorubicin. Benign mesothelial cells remained largely unaffected. Selenite potentiated doxorubicin treatment. Apoptosis was the dominating mode of cell death. The toxicity of selenite was mediated by oxidative stress. Furthermore the activity of the thioredoxin system was directly dependent on the concentration of selenite. This offers a possible mechanism of action of selenite treatment. Our findings suggest that selenite is a promising new drug for the treatment of malignant mesothelioma.

  18. Cytotoxicity and oxidative stress induced by different metallic nanoparticles on human kidney cells

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    Ohayon-Courtès Céline

    2011-03-01

    Full Text Available Abstract Background Some manufactured nanoparticles are metal-based and have a wide variety of applications in electronic, engineering and medicine. Until now, many studies have described the potential toxicity of NPs on pulmonary target, while little attention has been paid to kidney which is considered to be a secondary target organ. The objective of this study, on human renal culture cells, was to assess the toxicity profile of metallic nanoparticles (TiO2, ZnO and CdS usable in industrial production. Comparative studies were conducted, to identify whether particle properties impact cytotoxicity by altering the intracellular oxidative status. Results Nanoparticles were first characterized by size, surface charge, dispersion and solubility. Cytotoxicity of NPs was then evaluated in IP15 (glomerular mesangial and HK-2 (epithelial proximal cell lines. ZnO and CdS NPs significantly increased the cell mortality, in a dose-dependent manner. Cytotoxic effects were correlated with the physicochemical properties of NPs tested and the cell type used. Analysis of reactive oxygen species and intracellular levels of reduced and oxidized glutathione revealed that particles induced stress according to their composition, size and solubility. Protein involved in oxidative stress such as NF-κb was activated with ZnO and CdS nanoparticles. Such effects were not observed with TiO2 nanoparticles. Conclusion On glomerular and tubular human renal cells, ZnO and CdS nanoparticles exerted cytotoxic effects that were correlated with metal composition, particle scale and metal solubility. ROS production and oxidative stress induction clearly indicated their nephrotoxic potential.

  19. Oxidative stress modulates the cytokine response of differentiated Th17 and Th1 cells.

    Science.gov (United States)

    Abimannan, Thiruvaimozhi; Peroumal, Doureradjou; Parida, Jyoti R; Barik, Prakash K; Padhan, Prasanta; Devadas, Satish

    2016-10-01

    Reactive oxygen species (ROS) signaling is critical in T helper (Th) cell differentiation; however its role in differentiated Th cell functions is unclear. In this study, we investigated the role of oxidative stress on the effector functions of in vitro differentiated mouse Th17 and Th1 cells or CD4(+) T cells from patients with Rheumatoid Arthritis using pro-oxidants plumbagin (PB) and hydrogen peroxide. We found that in mouse Th cells, non-toxic concentration of pro-oxidants inhibited reactivation induced expression of IL-17A in Th17 and IFN-γ in Th1 cells by reducing the expression of their respective TFs, RORγt and T-bet. Interestingly, in both the subsets, PB increased the expression of IL-4 by enhancing reactivation induced ERK1/2 phosphorylation. We further investigated the cytokine modulatory effect of PB on CD4(+) T cells isolated from PBMCs of patients with Rheumatoid Arthritis, a well-known Th17 and or Th1 mediated disease. In human CD4(+) T cells from Rheumatoid Arthritis patients, PB reduced the frequencies of IL-17A(+) (Th17), IFN(-)γ(+) (Th1) and IL-17A(+)/IFN(-)γ(+) (Th17/1) cells and also inhibited the production of pro-inflammatory cytokines TNF-α and IL-6. N-Acetyl Cysteine (NAC) an antioxidant completely reversed PB mediated cytokine modulatory effects in both mouse and human cells indicating a direct role for ROS. Together our data suggest that oxidative microenvironment can alter cytokine response of terminally differentiated cells and thus altering intracellular ROS could be a potential way to target Th17 and Th1 cells in autoimmune disorders.

  20. Oxidative Stress and Antioxidant Defense

    OpenAIRE

    2012-01-01

    Abstract Reactive oxygen species (ROS) are produced by living organisms as a result of normal cellular metabolism and environmental factors, such as air pollutants or cigarette smoke. ROS are highly reactive molecules and can damage cell structures such as carbohydrates, nucleic acids, lipids, and proteins and alter their functions. The shift in the balance between oxidants and antioxidants in favor of oxidants is termed “oxidative stress.” Regulation of reducing and oxidizing (redox) state i...

  1. Oxidative stress and mitochondrial functions in the intestinal Caco-2/15 cell line.

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    Rame Taha

    Full Text Available BACKGROUND: Although mitochondrial dysfunction and oxidative stress are central mechanisms in various pathological conditions, they have not been extensively studied in the gastrointestinal tract, which is known to be constantly exposed to luminal oxidants from ingested foods. Key among these is the simultaneous consumption of iron salts and ascorbic acid, which can cause oxidative damage to biomolecules. METHODOLOGY/PRINCIPAL FINDINGS: The objective of the present work was to evaluate how iron-ascorbate (FE/ASC-mediated lipid peroxidation affects mitochondrion functioning in Caco-2/15 cells. Our results show that treatment of Caco-2/15 cells with FE/ASC (0.2 mM/2 mM (1 increased malondialdehyde levels assessed by HPLC; (2 reduced ATP production noted by luminescence assay; (3 provoked dysregulation of mitochondrial calcium homeostasis as evidenced by confocal fluorescence microscopy; (4 upregulated the protein expression of cytochrome C and apoptotic inducing factor, indicating exaggerated apoptosis; (5 affected mitochondrial respiratory chain complexes I, II, III and IV; (6 elicited mtDNA lesions as illustrated by the raised levels of 8-OHdG; (7 lowered DNA glycosylase, one of the first lines of defense against 8-OHdG mutagenicity; and (8 altered the gene expression and protein mass of mitochondrial transcription factors (mtTFA, mtTFB1, mtTFB2 without any effects on RNA Polymerase. The presence of the powerful antioxidant BHT (50 microM prevented the occurrence of oxidative stress and most of the mitochondrial abnormalities. CONCLUSIONS/SIGNIFICANCE: Collectively, our findings indicate that acute exposure of Caco-2/15 cells to FE/ASC-catalyzed peroxidation produces harmful effects on mitochondrial functions and DNA integrity, which are abrogated by the powerful exogenous BHT antioxidant. Functional derangements of mitochondria may have implications in oxidative stress-related disorders such as inflammatory bowel diseases.

  2. Autophagy prevents autophagic cell death in Tetrahymena in response to oxidative stress.

    Science.gov (United States)

    Zhang, Si-Wei; Feng, Jiang-Nan; Cao, Yi; Meng, Li-Ping; Wang, Shu-Lin

    2015-05-18

    Autophagy is a major cellular pathway used to degrade long-lived proteins or organelles that may be damaged due to increased reactive oxygen species (ROS) generated by cellular stress. Autophagy typically enhances cell survival, but it may also act to promote cell death under certain conditions. The mechanism underlying this paradox, however, remains unclear. We showed that Tetrahymena cells exerted increased membrane-bound vacuoles characteristic of autophagy followed by autophagic cell death (referred to as cell death with autophagy) after exposure to hydrogen peroxide. Inhibition of autophagy by chloroquine or 3-methyladenine significantly augmented autophagic cell death induced by hydrogen peroxide. Blockage of the mitochondrial electron transport chain or starvation triggered activation of autophagy followed by cell death by inducing the production of ROS due to the loss of mitochondrial membrane potential. This indicated a regulatory role of mitochondrial ROS in programming autophagy and autophagic cell death in Tetrahymena. Importantly, suppression of autophagy enhanced autophagic cell death in Tetrahymena in response to elevated ROS production from starvation, and this was reversed by antioxidants. Therefore, our results suggest that autophagy was activated upon oxidative stress to prevent the initiation of autophagic cell death in Tetrahymena until the accumulation of ROS passed the point of no return, leading to delayed cell death in Tetrahymena.

  3. Parkin elimination of mitochondria is important for maintenance of lens epithelial cell ROS levels and survival upon oxidative stress exposure.

    Science.gov (United States)

    Brennan, Lisa; Khoury, Josef; Kantorow, Marc

    2017-01-01

    Age-related cataract is associated with oxidative stress and death of lens epithelial cells (LECs) whose survival is dependent on functional mitochondrial populations. Oxidative stress-induced depolarization/damage of LEC mitochondria results in increased reactive oxygen species (ROS) levels and cell death suggesting the need for a LEC mechanism to remove mitochondria depolarized/damaged upon oxidative stress exposure to prevent ROS release and LEC death. To date, a mechanism(s) for removal of depolarized/damaged LEC mitochondria has yet to be identified and the importance of eliminating oxidative stress-damaged mitochondria to prevent LEC ROS release and death has not been established. Here, we demonstrate that Parkin levels increase in LECs exposed to H2O2-oxidative stress. We establish that Parkin translocates to LEC mitochondria depolarized upon oxidative stress exposure and that Parkin recruits p62/SQSTM1 to depolarized LEC mitochondria. We demonstrate that translocation of Parkin results in the elimination of depolarized/damaged mitochondria and that Parkin clearance of LEC mitochondria is dependent on its ubiquitin ligase activity. Importantly, we demonstrate that Parkin elimination of damaged LEC mitochondria results in reduced ROS levels and increased survival upon oxidative stress exposure. These results establish that Parkin functions to eliminate LEC mitochondria depolarized/damaged upon oxidative stress exposure and that elimination of damaged mitochondria by Parkin is important for LEC homeostasis and survival. The data also suggest that mitochondrial quality control by Parkin could play a role in lens transparency.

  4. Tart Cherry Extracts Reduce Inflammatory and Oxidative Stress Signaling in Microglial Cells.

    Science.gov (United States)

    Shukitt-Hale, Barbara; Kelly, Megan E; Bielinski, Donna F; Fisher, Derek R

    2016-09-22

    Tart cherries contain an array of polyphenols that can decrease inflammation and oxidative stress (OS), which contribute to cognitive declines seen in aging populations. Previous studies have shown that polyphenols from dark-colored fruits can reduce stress-mediated signaling in BV-2 mouse microglial cells, leading to decreases in nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression. Thus, the present study sought to determine if tart cherries-which improved cognitive behavior in aged rats-would be efficacious in reducing inflammatory and OS signaling in HAPI rat microglial cells. Cells were pretreated with different concentrations (0-1.0 mg/mL) of Montmorency tart cherry powder for 1-4 h, then treated with 0 or 100 ng/mL lipopolysaccharide (LPS) overnight. LPS application increased extracellular levels of NO and tumor necrosis factor-alpha (TNF-α), and intracellular levels of iNOS and cyclooxygenase-2 (COX-2). Pretreatment with tart cherry decreased levels of NO, TNF-α, and COX-2 in a dose- and time-dependent manner versus those without pretreatment; the optimal combination was between 0.125 and 0.25 mg/mL tart cherry for 2 h. Higher concentrations of tart cherry powder and longer exposure times negatively affected cell viability. Therefore, tart cherries (like other dark-colored fruits), may be effective in reducing inflammatory and OS-mediated signals.

  5. Tart Cherry Extracts Reduce Inflammatory and Oxidative Stress Signaling in Microglial Cells

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    Barbara Shukitt-Hale

    2016-09-01

    Full Text Available Tart cherries contain an array of polyphenols that can decrease inflammation and oxidative stress (OS, which contribute to cognitive declines seen in aging populations. Previous studies have shown that polyphenols from dark-colored fruits can reduce stress-mediated signaling in BV-2 mouse microglial cells, leading to decreases in nitric oxide (NO production and inducible nitric oxide synthase (iNOS expression. Thus, the present study sought to determine if tart cherries—which improved cognitive behavior in aged rats—would be efficacious in reducing inflammatory and OS signaling in HAPI rat microglial cells. Cells were pretreated with different concentrations (0–1.0 mg/mL of Montmorency tart cherry powder for 1–4 h, then treated with 0 or 100 ng/mL lipopolysaccharide (LPS overnight. LPS application increased extracellular levels of NO and tumor necrosis factor-alpha (TNF-α, and intracellular levels of iNOS and cyclooxygenase-2 (COX-2. Pretreatment with tart cherry decreased levels of NO, TNF-α, and COX-2 in a dose- and time-dependent manner versus those without pretreatment; the optimal combination was between 0.125 and 0.25 mg/mL tart cherry for 2 h. Higher concentrations of tart cherry powder and longer exposure times negatively affected cell viability. Therefore, tart cherries (like other dark-colored fruits, may be effective in reducing inflammatory and OS-mediated signals.

  6. Early single cell bifurcation of pro- and antiapoptotic states during oxidative stress.

    Science.gov (United States)

    Nair, Venugopalan D; Yuen, Tony; Olanow, C Warren; Sealfon, Stuart C

    2004-06-25

    In a population of cells undergoing oxidative stress, an individual cell either succumbs to apoptotic cell death or maintains homeostasis and survives. Exposure of PC-12-D(2)R cells to 200 microm hydrogen peroxide (H(2)O(2)) induces apoptosis in about half of cells after 24 h. After 1-h exposure to 200 microm H(2)O(2), both antiapoptotic extracellular regulated kinase (ERK) phosphorylation and pro-apoptotic Ser-15-p53 phosphorylation are observed. Microarray and real-time PCR assays of gene expression after H(2)O(2) exposure identified several transcripts, including egr1, that are rapidly induced downstream of ERK. Single cell analysis of egr1 induction and of phospho-ERK and phospho-p53 formation revealed the presence of two distinct cellular programs. Whereas the proportion of cells activating ERK versus p53 at 1 h depended on H(2)O(2) concentration, individual cells showed exclusively either phospho-p53 formation or activation of ERK and egr1 induction. Exposure to H(2)O(2) for 1 h also elicited these two non-overlapping cellular responses in both dopaminergic SN4741 cells and differentiated postmitotic PC-12-D(2)R cells. Repressing p53 with pifithrin-alpha or small interfering RNA increased ERK phosphorylation by H(2)O(2), indicating that p53-dependent suppression of ERK activity may contribute to the bi-stable single cell responses observed. By 24 h, the subset of cells in which ERK activity was suppressed exhibit caspase 3 activation and the nuclear condensation characteristic of apoptosis. These studies suggest that the individual cell rapidly and stochastically processes the oxidative stress stimulus, leading to an all-or-none cytoprotective or pro-apoptotic signaling response.

  7. Epoetin Delta Reduces Oxidative Stress in Primary Human Renal Tubular Cells

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    Annelies De Beuf

    2010-01-01

    Full Text Available Erythropoietin (EPO exerts (renal tissue protective effects. Since it is unclear whether this is a direct effect of EPO on the kidney or not, we investigated whether EPO is able to protect human renal tubular epithelial cells (hTECs from oxidative stress and if so which pathways are involved. EPO (epoetin delta could protect hTECs against oxidative stress by a dose-dependent inhibition of reactive oxygen species formation. This protective effect is possibly related to the membranous expression of the EPO receptor (EPOR since our data point to the membranous EPOR expression as a prerequisite for this protective effect. Oxidative stress reduction went along with the upregulation of renoprotective genes. Whilst three of these, heme oxygenase-1 (HO-1, aquaporin-1 (AQP-1, and B-cell CLL/lymphoma 2 (Bcl-2 have already been associated with EPO-induced renoprotection, this study for the first time suggests carboxypeptidase M (CPM, dipeptidyl peptidase IV (DPPIV, and cytoglobin (Cygb to play a role in this process.

  8. Antioxidative and neuroprotective activities of peanut sprout extracts against oxidative stress in SK-N-SH cells

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    Pranee Lertkaeo

    2017-01-01

    Conclusions: PSE has neuroprotective activities against oxidative stress in SK-N-SH cells induced by PQ, suggesting that PSE is a highly promising agent in the prevention of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease.

  9. Cadmium Chloride Induces DNA Damage and Apoptosis of Human Liver Carcinoma Cells via Oxidative Stress

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    Anthony Skipper

    2016-01-01

    Full Text Available Cadmium is a heavy metal that has been shown to cause its toxicity in humans and animals. Many documented studies have shown that cadmium produces various genotoxic effects such as DNA damage and chromosomal aberrations. Ailments such as bone disease, renal damage, and several forms of cancer are attributed to overexposure to cadmium.  Although there have been numerous studies examining the effects of cadmium in animal models and a few case studies involving communities where cadmium contamination has occurred, its molecular mechanisms of action are not fully elucidated. In this research, we hypothesized that oxidative stress plays a key role in cadmium chloride-induced toxicity, DNA damage, and apoptosis of human liver carcinoma (HepG2 cells. To test our hypothesis, cell viability was determined by MTT assay. Lipid hydroperoxide content stress was estimated by lipid peroxidation assay. Genotoxic damage was tested by the means of alkaline single cell gel electrophoresis (Comet assay. Cell apoptosis was measured by flow cytometry assessment (Annexin-V/PI assay. The result of MTT assay indicated that cadmium chloride induces toxicity to HepG2 cells in a concentration-dependent manner, showing a 48 hr-LD50 of 3.6 µg/mL. Data generated from lipid peroxidation assay resulted in a significant (p < 0.05 increase of hydroperoxide production, specifically at the highest concentration tested. Data obtained from the Comet assay indicated that cadmium chloride causes DNA damage in HepG2 cells in a concentration-dependent manner. A strong concentration-response relationship (p < 0.05 was recorded between annexin V positive cells and cadmium chloride exposure. In summary, these in vitro studies provide clear evidence that cadmium chloride induces oxidative stress, DNA damage, and programmed cell death in human liver carcinoma (HepG2 cells.

  10. Protection of human HepG2 cells against oxidative stress by cocoa phenolic extract.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Granado Serrano, Ana Belén; Izquierdo-Pulido, María; Bravo, Laura; Goya, Luis

    2008-09-10

    Cocoa is a rich source of flavanols and procyanidin oligomers with antioxidative properties, providing protection against oxidation and nitration. The present study investigated the potential protective effect of a polyphenolic extract from cocoa on cell viability and antioxidant defenses of cultured human HepG2 cells submitted to oxidative stress induced by tert-butylhydroperoxide (t-BOOH). Pretreatment of cells with 0.05-50 microg/mL of cocoa polyphenolic extract (CPE) for 2 or 20 h completely prevented cell damage and enhanced activity of antioxidant enzymes induced by a treatment with t-BOOH. Moreover, lower levels of GSH caused by t-BOOH in HepG2 cells were partly recovered by a pretreatment with CPE. Increased reactive oxygen species (ROS) induced by t-BOOH was dose-dependently prevented when cells were pretreated for 2 or 20 h with CPE. These results show that treatment of HepG2 in culture with CPE (within the physiological range of concentrations) confers a significant protection against oxidation to the cells.

  11. Oxidative damage and cell-programmed death induced in Zea mays L. by allelochemical stress.

    Science.gov (United States)

    Ciniglia, Claudia; Mastrobuoni, Francesco; Scortichini, Marco; Petriccione, Milena

    2015-05-01

    The allelochemical stress on Zea mays was analyzed by using walnut husk washing waters (WHWW), a by-product of Juglans regia post-harvest process, which possesses strong allelopathic potential and phytotoxic effects. Oxidative damage and cell-programmed death were induced by WHWW in roots of maize seedlings. Treatment induced ROS burst, with excess of H2O2 content. Enzymatic activities of catalase were strongly increased during the first hours of exposure. The excess in malonildialdehyde following exposure to WHWW confirmed that oxidative stress severely damaged maize roots. Membrane alteration caused a decrease in NADPH oxidase activity along with DNA damage as confirmed by DNA laddering. The DNA instability was also assessed through sequence-related amplified polymorphism assay, thus suggesting the danger of walnut processing by-product and focusing the attention on the necessity of an efficient treatment of WHWW.

  12. Natural Products Mediated Regulation of Oxidative Stress and DNA Damage in Ultraviolet Exposed Skin Cells.

    Science.gov (United States)

    Farooqi, Ammad A; Li, Ruei-Nian; Huang, Hurng-Wern; Ismail, Muhammad; Yuan, Shyng-Shiou F; Wang, Hui-Min D; Liu, Jing-Ru; Tang, Jen-Yang; Chang, Hsueh-Wei

    2015-01-01

    Data obtained through high-throughput technologies have gradually revealed that a unique stratified epithelial architecture of human skin along with the antioxidant-response pathways provided vital defensive mechanisms against UV radiation. However, it is noteworthy that skin is a major target for toxic insult by UV radiations that can alter its structure and function. Substantial fraction of information has been added into the existing pool of knowledge related to natural products mediated biological effects in UV exposed skin cells. Accumulating evidence has started to shed light on the potential of these bioactive ingredients as protective natural products in cosmetics against UV photodamage by exerting biological effects mainly through wide ranging intracellular signalling cascades of oxidative stress and modulation of miRNAs. In this review, we have summarized recently emerging scientific evidences addressing underlying mechanisms of UV induced oxidative stress and deregulation of signalling cascades and how natural products can be used tactfully to protect against UV induced harmful effects.

  13. Urate Oxidase Knockdown Decreases Oxidative Stress in a Murine Hepatic Cell Line

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    Beth M. Cleveland

    2009-01-01

    Full Text Available Humans, birds, and some primates do not express the uric acid degrading enzyme urate oxidase (UOX and, as a result, have plasma uric acid concentrations higher than UOX expressing animals. Although high uric acid concentrations are suggested to increase the antioxidant defense system and provide a health advantage to animals without UOX, knockout mice lacking UOX develop pathological complications including gout and kidney failure. As an alternative to the knockout model, RNA interference was used to decrease UOX expression using stable transfection in a mouse hepatic cell line (ATCC, FL83B. Urate oxidase mRNA was reduced 66% (p < 0.05 compared to wild type, as measured by real time RT-PCR. To determine if UOX knockdown resulted in enhanced protection against oxidative stress, cells were challenged with hexavalent chromium (Cr(VI or 3-morpholinosydnonimine hydrochloride (SIN-1. Compared to wild type, cells with UOX knockdown exhibited a 37.2 ± 3.5% reduction (p < 0.05 in the electron spin resonance (ESR signal after being exposed to Cr(VI and displayed less DNA fragmentation (p < 0.05 following SIN-1 treatment. Cell viability decreased in wild type cells (p < 0.05, but not cells with UOX knockdown, after treatment with SIN-1. These results are consistent with an increased intracellular uric acid concentration and an increased defense against oxidative stress.

  14. Toxin release in response to oxidative stress and programmed cell death in the cyanobacterium Microcystis aeruginosa

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Cliff [Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Ft. Pierce, FL 34949 (United States)]. E-mail: Ross@sms.si.edu; Santiago-Vazquez, Lory [Department of Chemistry and Biochemistry, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431 (United States); Paul, Valerie [Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Ft. Pierce, FL 34949 (United States)

    2006-06-10

    An unprecedented bloom of the cyanobacterium Microcystis aeruginosa Kuetz. occurred in the St. Lucie Estuary, FL in the summer of 2005. Samples were analyzed for toxicity by ELISA and by use of the polymerase chain reaction (PCR) with specific oligonucleotide primers for the mcyB gene that has previously been correlated with the biosynthesis of toxic microcystins. Despite the fact that secreted toxin levels were relatively low in dense natural assemblages (3.5 {mu}g l{sup -1}), detectable toxin levels increased by 90% when M. aeruginosa was stressed by an increase in salinity, physical injury, application of the chemical herbicide paraquat, or UV irradiation. The application of the same stressors caused a three-fold increase in the production of H{sub 2}O{sub 2} when compared to non-stressed cells. The application of micromolar concentrations of H{sub 2}O{sub 2} induced programmed cell death (PCD) as measured by a caspase protease assay. Catalase was capable of inhibiting PCD, implicating H{sub 2}O{sub 2} as the inducing oxidative species. Our results indicate that physical stressors induce oxidative stress, which results in PCD and a concomitant release of toxin into the surrounding media. Remediation strategies that induce cellular stress should be approached with caution since these protocols are capable of releasing elevated levels of microcystins into the environment.

  15. Immunomodulatory Properties of Mesenchymal Stem Cells Can Mitigate Oxidative Stress and Inflammation Process in Human Mustard Lung.

    Science.gov (United States)

    Nejad-Moghaddam, Amir; Ajdary, Sohiela; Tahmasbpour, Eisa; Rad, Farhad Riazi; Panahi, Yunes; Ghanei, Mostafa

    2016-12-01

    Oxidative stress and inflammation are one of the main pathological consequences of sulfur mustard on human lungs. Unfortunately, there is no effective treatment to mitigate pathological effects of sulfur mustard in mustard lungs. Here, we aimed to evaluate potential efficacy of systemic mesenchymal stem cells administration on expression of oxidative stress- and inflammation-related genes in sulfur mustard-exposed patients. Our patient received 100 million cells per injection, which was continued for four injections within 2 months. Sputum samples were provided after each injection. Oxidative stress was evaluated by determining sputum levels of malondialdehyde and glutathione. Furthermore, changes in expression of several oxidative stress- (metallothionein 3, glutathione reductase, oxidative stress responsive 1, glutathione peroxidase 2, lacto peroxidase, forkhead box M1) and inflammation-related genes (matrix metallopeptidase 2, matrix metallopeptidase 9, transforming growth factor-β1, vascular endothelial growth factor, metallopeptidase inhibitor 1, metallopeptidase inhibitor 2) were also evaluated using real-time PCR after treatments. Two-lung epithelial-specific proteins including Clara cell protein 16 and Mucin-1 protein levels were measured using enzyme immunoassay method. No significant differences were found between serum levels of Clara cell protein 16 and serum Mucin-1 protein in patient before and after cell therapy. Most of the oxidative stress responsive genes, particularly oxidative stress responsive 1, were overexpressed after treatments. Expressions of antioxidants genes such as metallothionein 3, glutathione reductase and glutathione peroxidase 2 were increased after cell therapy. Upon comparison of inflammation-related genes, we observed upregulation of vascular endothelial growth factor and matrix metallopeptidase 9 after mesenchymal stem cells therapy. Additionally, a trend for increased value of glutathione and decreased levels of

  16. Benzothiazole Amphiphiles Ameliorate Amyloid β-Related Cell Toxicity and Oxidative Stress.

    Science.gov (United States)

    Cifelli, Jessica L; Chung, Tim S; Liu, Haiyan; Prangkio, Panchika; Mayer, Michael; Yang, Jerry

    2016-06-15

    Oxidative stress from the increase of reactive oxygen species in cells is a common part of the normal aging process and is accelerated in patients with Alzheimer's disease (AD). Herein, we report the evaluation of three benzothiazole amphiphiles (BAMs) that exhibit improved biocompatibility without loss of biological activity against amyloid-β induced cell damage compared to a previously reported hexa(ethylene glycol) derivative of benzothiazole aniline (BTA-EG6). The reduced toxicity of these BAM agents compared to BTA-EG6 corresponded with their reduced propensity to induce membrane lysis. In addition, all of the new BAMs were capable of protecting differentiated SH-SY5Y neuroblastoma cells from toxicity and concomitant oxidative stress induced by AD-related aggregated Aβ (1-42) peptides. Binding and microscopy studies support that these BAM agents target Aβ and inhibit the interactions of catalase with Aβ in cells, which, in turn, can account for an observed inhibition of Aβ-induced increases in hydrogen peroxide in cells treated with these compounds. These results support that this family of benzothiazole amphiphiles may have therapeutic potential for treating cellular damage associated with AD and other Aβ-related neurologic diseases.

  17. Protective mechanism of agmatine pretreatment on RGC-5 cells injured by oxidative stress

    Directory of Open Access Journals (Sweden)

    Y. Iizuka

    2010-04-01

    Full Text Available Agmatine has neuroprotective effects on retinal ganglion cells (RGCs as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line. Differentiated RGC-5 cells were pretreated with 100 μM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2. Cell viability was determined by measuring lactate dehydrogenase (LDH, and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM and N-methyl-D-aspartic acid (NMDA receptor agonist NMDA (0-100 µM were evaluated. Agmatine’s protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50%, which was reduced to about 30% when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatine’s protective effect, but NMDA did not. In addition, MK-801 (0-100 µM did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.

  18. Safety of Desmodium adscendens extract on hepatocytes and renal cells. Protective effect against oxidative stress.

    Directory of Open Access Journals (Sweden)

    C. Francois

    2015-03-01

    RESULTS: A viability test (MTS, a cytotoxicity assay (LDH release and a study of the cell morphology revealed that pretreatment with 1 mg/ml or 10 mg/ml DA did not alter viability or LDH release in HEPG2 or LLCPK1 cells. However, DA at the dose of 100 mg/ml significantly decreased cell viability, by about 40% (P <0.05. Further, MTS studies revealed that DA 1 mg/ml or 10 mg/ml protected LLC-PK1 cells against a glucose-induced oxidative stress of 24 hours (P<0.05. CONCLUSION: Hence, the lowest concentrations of DA (1mg/ml and 10mg/ml were safe for HEPG2 and LLCPK1 and protective against an oxidative stress in LLC-PK1 cells. These data suggest that DA extracts used as a traditional herbal as food health supplements should be used at the lowest dosage. [J Intercult Ethnopharmacol 2015; 4(1.000: 1-5

  19. Oxidative stress and apoptosis in intrinsic renal cell populations - an in vitro study

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    Gobe, G.C.; Hogg, N.; Schoch, E.; James, M.; Willgoss, D.; Endre, Z. [University of Queensland, Brisbane, QLD (Australia)

    1996-12-31

    The authors have been studying the interaction between incidence of apoptosis and expression of selected oncogenes and cytokines in an in vivo rat model of ischaemia-reperfusion injury. The ischaemia itself, and the reperfusion, induce oxidative damage to the tissues, including damage from oxygen-derived free radicals. The scenario is therefore similar to radiation-induced injury. The proximal nephron segments, especially the pars recta, are usually acutely sensitive to ischaemia-reperfusion injury, undergoing necrosis in preference to apoptosis. A hypothesis was formed that Bcl-2 protection of the distal nephron, a segment of the nephron known as a reservoir for many growth factors or cytokines, allows increased production of growth factors during oxidative stress, which then act in a paracrine manner to protect the nearby proximal tubule. To test this hypothesis, an in vitro model of oxidative stress was used on either distal (Madin Derby Canine Kidney, MDCK) or proximal (human kidney-2, HK-2) established renal cell lines. We grow the cells as `coverslip cultures` in 12-well plates in Dulbecco`s Modified Eagle`s Medium or serum free medium. The treatments used are either hydrogen peroxide (a gradation of concentrations from 1mM to 50 mM), tumour necrosis factor-alpha (TNF-alpha) or hypoxia, as inducers of oxidative stress. The parameters analysed in the present study were (i) cell death (apoptosis or necrosis, using histology, in situ end labelling, and electron microscopy) (ii) cell proliferation and (iii) Bcl-2 expression (immunohistochemistry). It was found that all treatments increase levels of apoptosis in both cell lines, and TNF-alpha also causes increased cell proliferation. At the higher concentrations of hydrogen peroxide however, the HK-2 (proximal) cells have more of a tendency to undergo necrosis than do the MDCK (distal) cells, mimicking the in vivo situation. Bcl-2 expression is low in both cell lines, and does not appear to be affected by the

  20. Multi wall carbon nanotubes induce oxidative stress and cytotoxicity in human embryonic kidney (HEK293) cells.

    Science.gov (United States)

    Reddy, Anreddy Rama Narsimha; Reddy, Yellu Narsimha; Krishna, Devarakonda Rama; Himabindu, Vurimindi

    2010-06-04

    The present study was aimed at evaluating the potential toxicity and the general mechanism involved in multi wall carbon nanotubes (MWCNT)-induced cytotoxicity using human embryonic kidney cell line (HEK293) cells. Two multi wall carbon nanotubes (coded as MWCNT1, size: 90-150nm and MWCNT2, size: 60-80nm) used in this study are MWCNT1 (produced by the electric arc method and size of the nanotubes was 90-150nm) and MWCNT2 (produced by the chemical vapor deposition method with size of 60-80nm). To elucidate the possible mechanisms of MWCNT induced cytotoxicity, cell viability, mitochondrial function (MTT assay), cell membrane damage (LDH assay), reduced glutathione (GSH), interleukin-8 (IL-8) and lipid peroxidation levels were quantitatively assessed under carbon nanotubes exposed (48h) conditions. Exposure of different sizes of two carbon nanotubes at dosage levels between 3 and 300mug/ml decreased cell viability in a concentration dependent manner. The IC(50) values (concentration of nanoparticles to induce 50% cell mortality) of two (MWCNT1, MWCNT2) nanoparticles were found as 42.10 and 36.95mug/ml. Exposure of MWCNT (10-100mug/ml) to HEK cells resulted in concentration dependent cell membrane damage (as indicated by the increased levels of LDH), increased production of IL-8, increased TBARS and decreased intracellular glutathione levels. The cytotoxicity and oxidative stress was significantly more in MWCNT2 exposed cells than MWCNT1. In summary, exposure of carbon nanotubes resulted in a concentration dependent cytotoxicity in cultured HEK293 cells that was associated with increased oxidative stress.

  1. Modulation of Apoptosis Pathways by Oxidative Stress and Autophagy in β Cells

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    Maorong Wang

    2012-01-01

    Full Text Available Human islets isolated for transplantation are exposed to multiple stresses including oxidative stress and hypoxia resulting in significant loss of functional β cell mass. In this study we examined the modulation of apoptosis pathway genes in islets exposed to hydrogen peroxide, peroxynitrite, hypoxia, and cytokines. We observed parallel induction of pro- and antiapoptotic pathways and identified several novel genes including BFAR, CARD8, BNIP3, and CIDE-A. As BNIP3 is an inducer of autophagy, we examined this pathway in MIN6 cells, a mouse beta cell line and in human islets. Culture of MIN6 cells under low serum conditions increased the levels of several proteins in autophagy pathway, including ATG4, Beclin 1, LAMP-2, and UVRAG. Amino acid deprivation led to induction of autophagy in human islets. Preconditioning of islets with inducers of autophagy protected them from hypoxia-induced apoptosis. However, induction of autophagy during hypoxia exacerbated apoptotic cell death. ER stress led to induction of autophagy and apoptosis in β cells. Overexpression of MnSOD, an enzyme that scavenges free radicals, resulted in protection of MIN6 cells from cytokine-induced apoptosis. Ceramide, a mediator of cytokine-induced injury, reduced the active phosphorylated form of Akt and downregulated the promoter activity of the antiapoptotic gene bcl-2. Furthermore, cytokine-stimulated JNK pathway downregulated the bcl-2 promoter activity which was reversed by preincubation with SP600125, a JNK inhibitor. Our findings suggest that β cell apoptosis by multiple stresses in islets isolated for transplantation is the result of orchestrated gene expression in apoptosis pathway.

  2. Dexamethasone acts as a radiosensitizer in three astrocytoma cell lines via oxidative stress.

    Science.gov (United States)

    Ortega-Martínez, Sylvia

    2015-08-01

    Glucocorticoids (GCs), which act on stress pathways, are well-established in the co-treatment of different kinds of tumors; however, the underlying mechanisms by which GCs act are not yet well elucidated. As such, this work investigates the role of glucocorticoids, specifically dexamethasone (DEXA), in the processes referred to as DNA damage and DNA damage response (DDR), establishing a new approach in three astrocytomas cell lines (CT2A, APP.PS1 L.1 and APP.PS1 L.3). The results show that DEXA administration increased the basal levels of gamma-H2AX foci, keeping them higher 4h after irradiation (IR) of the cells, compared to untreated cells. This means that DEXA might cause increased radiosensitivity in these cell lines. On the other hand, DEXA did not have an apparent effect on the formation and disappearance of the 53BP1 foci. Furthermore, it was found that DEXA administered 2h before IR led to a radical change in DNA repair kinetics, even DEXA does not affect cell cycle. It is important to highlight that DEXA produced cell death in these cell lines compared to untreated cells. Finally and most important, the high levels of gamma-H2AX could be reversed by administration of ascorbic acid, a potent blocker of reactive oxygen species, suggesting that DEXA acts by causing DNA damage via oxidative stress. These exiting findings suggest that DEXA might promote radiosensitivity in brain tumors, specifically in astrocytoma-like tumors.

  3. PUFA and oxidative stress. Differential modulation of the cell response by DHA.

    Science.gov (United States)

    Di Nunzio, Mattia; Valli, Veronica; Bordoni, Alessandra

    2016-11-01

    Although an increased dietary intake of long-chain n-3 PUFA is considered an effective preventive strategy, a theoretical concern related to the possible increase of lipid peroxidation induced by a PUFA-rich diet still remains a problem. In this study, the effects of different PUFA (linoleic, α-linolenic, arachidonic, eicosapentaenoic and docosahexaenoic acid) on cytotoxicity, lipid oxidation, and modulation of antioxidant defenses were evaluated in HepG2 cells submitted to an oxidative stress (H2O2). Results clearly evidenced that all supplemented PUFA, but DHA, enhanced cell susceptibility to H2O2. Overall, our results underline that PUFA cannot be considered as a single category but as individual compounds, and research on mechanisms of action and preventive effects should deal with the individual fatty acids, particularly in the case of DHA.

  4. Biscuit melanoidins of different molecular masses protect human HepG2 cells against oxidative stress.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Rufián-Henares, José Angel; Morales, Francisco José; Bravo, Laura; Goya, Luis

    2009-08-26

    Soluble melanoidins from biscuits were enzymatically solubilized and isolated by sequential ultrafiltration and separated by molecular mass in three different fractions, below 3 kDa, between 3 and 10 kDa, and over 10 kDa; the latter was subsequently digested by simulating gastric plus pancreatic digestive conditions. The four fractions were investigated for their protective effect against an oxidative challenge in HepG2 cells. Pretreatment of cells for 20 h with 0.5-10 microg/mL of any of the four fractions prevented the increased cell damage evoked by the challenge but, except for the intermediate size fraction, did not suppress the increased reactive oxygen species. Antioxidant defenses were rapidly restored after the challenge, and the increase of the oxidative stress biomarker malondialdehyde was prevented by the pretreatment with all but the undigested high molecular mass fraction. The results show that treatment of HepG2 cells with concentrations of biscuit melanoidins within the expected physiological range confers on the cells a significant protection against an oxidative challenge.

  5. Sulindac enhances the killing of cancer cells exposed to oxidative stress.

    Directory of Open Access Journals (Sweden)

    Maria Marchetti

    Full Text Available BACKGROUND: Sulindac is an FDA-approved non-steroidal anti-inflammatory drug (NSAID that affects prostaglandin production by inhibiting cyclooxygenases (COX 1 and 2. Sulindac has also been of interest for more than decade as a chemopreventive for adenomatous colorectal polyps and colon cancer. PRINCIPAL FINDINGS: Pretreatment of human colon and lung cancer cells with sulindac enhances killing by an oxidizing agent such as tert-butyl hydroperoxide (TBHP or hydrogen peroxide. This effect does not involve cyclooxygenase (COX inhibition. However, under the conditions used, there is a significant increase in reactive oxygen species (ROS within the cancer cells and a loss of mitochondrial membrane potential, suggesting that cell death is due to apoptosis, which was confirmed by Tunel assay. In contrast, this enhanced killing was not observed with normal lung or colon cells. SIGNIFICANCE: These results indicate that normal and cancer cells handle oxidative stress in different ways and sulindac can enhance this difference. The combination of sulindac and an oxidizing agent could have therapeutic value.

  6. Effects of Selenium Yeast on Oxidative Stress, Growth Inhibition, and Apoptosis in Human Breast Cancer Cells.

    Science.gov (United States)

    Guo, Chih-Hung; Hsia, Simon; Shih, Min-Yi; Hsieh, Fang-Chin; Chen, Pei-Chung

    2015-01-01

    Recent evidence suggests that selenium (Se) yeast may exhibit potential anti-cancer properties; whereas the precise mechanisms remain unknown. The present study was aimed at evaluating the effects of Se yeast on oxidative stress, growth inhibition, and apoptosis in human breast cancer cells. Treatments of ER-positive MCF-7 and triple-negative MDA-MB-231 cells with Se yeast (100, 750, and 1500 ng Se/mL), methylseleninic acid (MSA, 1500 ng Se/mL), or methylselenocysteine (MSC, 1500 ng Se/mL) at a time course experiment (at 24, 48, 72, and 96 h) were analyzed. Se yeast inhibited the growth of these cancer cells in a dose- and time-dependent manner. Compared with the same level of MSA, cancer cells exposure to Se yeast exhibited a lower growth-inhibitory response. The latter has also lower superoxide production and reduced antioxidant enzyme activities. Furthermore, MSA (1500 ng Se/mL)-exposed non-tumorigenic human mammary epithelial cells (HMEC) have a significant growth inhibitory effect, but not Se yeast and MSC. Compared with MSA, Se yeast resulted in a greater increase in the early apoptosis in MCF-7 cells as well as a lower proportion of early and late apoptosis in MDA-MB-231 cells. In addition, nuclear morphological changes and loss of mitochondrial membrane potential were observed. In conclusion, a dose of 100 to 1500 ng Se/mL of Se yeast can increase oxidative stress, and stimulate growth inhibitory effects and apoptosis induction in breast cancer cell lines, but does not affect non-tumorigenic cells.

  7. Effects of Nebivolol on Endothelial Gene Expression during Oxidative Stress in Human Umbilical Vein Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ulisse Garbin

    2008-01-01

    Full Text Available The endothelium plays a key role in the development of atherogenesis and its inflammatory and proliferative status influences the progression of atherosclerosis. The aim of this study is to compare the effects of two beta blockers such as nebivolol and atenolol on gene expression in human umbilical vein endothelial cells (HUVECs following an oxidant stimulus. HUVECs were incubated with nebivolol or atenolol (10 micromol/L for 24 hours and oxidative stress was induced by the addition of oxidized (ox-LDL. Ox-LDL upregulated adhesion molecules (ICAM-1, ICAM-2, ICAM-3, E-selectin, and P-selectin; proteins linked to inflammation (IL-6 and TNFalpha, thrombotic state (tissue factor, PAI-1 and uPA, hypertension such as endothelin-1 (ET-1, and vascular remodeling such as metalloproteinases (MMP-2, MMP-9 and protease inhibitor (TIMP-1. The exposure of HUVECs to nebivolol, but not to atenolol, reduced these genes upregulated by oxidative stress both in terms of protein and RNA expression. The known antioxidant properties of the third generation beta blocker nebivolol seem to account to the observed differences seen when compared to atenolol and support the specific potential protective role of this beta blocker on the expression of a number of genes involved in the initiation and progression of atherosclerosis.

  8. Red blood cells sensitivity to oxidative stress in the presence of low concentrations of uranium compound

    Energy Technology Data Exchange (ETDEWEB)

    Shevchenko, O.G. [Institute of Biology, Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 167982, Syktyvkar (Russian Federation)

    2014-07-01

    Uranium is a natural radioactive element widespread in biosphere. There are a few works that examined cellular and molecular mechanisms of uranium toxicity. Red blood cells are classical model to investigate toxicity mechanisms on cell membrane system. The aim of present work is to study the effect of uranyl ion in nano-molar concentrations on erythrocytes sensitivity (in vitro) to factors provoking acute oxidative stress. Uranyl ions were added to suspension of mice red blood cells in PBS as UO{sub 2}Cl{sub 2} solution. Samples were incubated in a thermostatic shaker at 37 deg. C during 3-5 hours. Than acute oxidative stress was induced by H{sub 2}O{sub 2} (0.9 mM) or AAPH (5 mM) solutions. Destabilization of the membrane was induced by nonionic detergent Triton X-100. The hemolysis degree and the content of LPO secondary products reacting with 2-thiobarbituric acid in the incubation mixture were determined spectrophotometrically. The ratio of hemoglobin various forms (oxyHb, metHb and ferrylHb) was calculated taking into account extinction coefficients. It was shown that uranyl chloride enhances cell sensitivity to nonionic detergent Triton X-100 effects, indicating alterations of membrane acyl chain order due to contact with the radionuclide ions. Uranium exposure also caused an increase in the cell sensitivity to the AAPH effects, resulted in a decrease in red cell survival rate, a sharp increase in accumulation of hemoglobin oxidation products and a slight increase in the concentration of LPO secondary products. Thus, uranyl ions change physicochemical properties of the erythrocyte membranes that resulted in increased sensitivity to effects of peroxyl radicals formed by thermal decomposition of AAPH. On the contrary, use of another source of free radicals - H{sub 2}O{sub 2} - after uranyl ions exposure resulted in marked decrease of oxidative hemolysis, inhibition of LPO and hemoglobin oxidation. Since the uranium chemical properties similar to properties of

  9. Methylglyoxal induces oxidative stress and mitochondrial dysfunction in osteoblastic MC3T3-E1 cells.

    Science.gov (United States)

    Suh, K S; Choi, E M; Rhee, S Y; Kim, Y S

    2014-02-01

    Methylglyoxal is a reactive dicarbonyl compound produced by glycolytic processing and identified as a precursor of advanced glycation end products. The elevated methylglyoxal levels in patients with diabetes are believed to contribute to diabetic complications, including bone defects. The objective of this study was to evaluate the effect of methylglyoxal on the function of osteoblastic MC3T3-E1 cells. The data indicated that methylglyoxal decreased osteoblast differentiation and induced osteoblast cytotoxicity. Pretreatment of MC3T3-E1 cells with aminoguanidine (a carbonyl scavenger), Trolox (an antioxidant), and cyclosporin A (a blocker of the mitochondrial permeability transition pore) prevented methylglyoxal-induced cytotoxicity in MC3T3-E1 cells. However, BAPTA/AM (an intracellular Ca(2+) chelator) and dantrolene (an inhibitor of endoplasmic reticulum Ca(2+) release) did not reverse the cytotoxic effect of methylglyoxal. Methylglyoxal increased the formation of intracellular reactive oxygen species, mitochondrial superoxide, and cardiolipin peroxidation in osteoblastic MC3T3-E1 cells. Methylglyoxal also decreased the mitochondrial membrane potential and intracellular ATP and nitric oxide levels, suggesting that carbonyl stress-induced loss of mitochondrial integrity contributes to the cytotoxicity of methylglyoxal. Furthermore, the results demonstrated that methylglyoxal induced protein adduct formation, inactivation of glyoxalase I, and activation of glyoxalase II. Aminoguanidine reversed all aforementioned effects of methylglyoxal. Taken together, these data support the notion that high methylglyoxal concentrations have detrimental effects on osteoblasts through a mechanism involving oxidative stress and mitochondrial dysfunction.

  10. The red-vine-leaf extract AS195 increases nitric oxide synthase-dependent nitric oxide generation and decreases oxidative stress in endothelial and red blood cells.

    Science.gov (United States)

    Grau, Marijke; Bölck, Birgit; Bizjak, Daniel Alexander; Stabenow, Christina Julia Annika; Bloch, Wilhelm

    2016-02-01

    The red-vine-leaf extract AS195 improves cutaneous oxygen supply and the microcirculation in patients suffering from chronic venous insufficiency. Regulation of blood flow was associated to nitric oxide synthase (NOS)-dependent NO (nitric oxide) production, and endothelial and red blood cells (RBC) have been shown to possess respective NOS isoforms. It was hypothesized that AS195 positively affects NOS activation in human umbilical vein endothelial cells (HUVECs) and RBC. Because patients with microvascular disorders show increased oxidative stress which limits NO bioavailability, it was further hypothesized that AS195 increases NO bioavailability by decreasing the content of reactive oxygen species (ROS) and increasing antioxidant capacity. Cultured HUVECs and RBCs from healthy volunteers were incubated with AS195 (100 μmol/L), tert-butylhydroperoxide (TBHP, 1 mmol/L) to induce oxidative stress and with both AS195 and TBHP. Endothelial and red blood cell-nitric oxide synthase (RBC-NOS) activation significantly increased after AS195 incubation. Nitrite concentration, a marker for NO production, increased in HUVEC but decreased in RBC after AS195 application possibly due to nitrite scavenging potential of flavonoids. S-nitrosylation of RBC cytoskeletal spectrins and RBC deformability were increased after AS195 incubation. TBHP-induced ROS were decreased by AS195, and antioxidative capacity was significantly increased in AS195-treated cells. TBHP also reduced RBC deformability, but reduction was attenuated by parallel incubation with AS195. Adhesion of HUVEC was also reduced after AS195 treatment. Red-vine-leaf extract AS195 increases NOS activation and decreases oxidative stress. Both mechanisms increase NO bioavailability, improve cell function, and may thus account for enhanced microcirculation in both health and disease.

  11. A review of adaptive mechanisms in cell responses towards oxidative stress caused by dental resin monomers.

    Science.gov (United States)

    Krifka, Stephanie; Spagnuolo, Gianrico; Schmalz, Gottfried; Schweikl, Helmut

    2013-06-01

    Dental composite resins are biomaterials commonly used to aesthetically restore the structure and function of teeth impaired by caries, erosion, or fracture. Residual monomers released from resin restorations as a result of incomplete polymerization processes interact with living oral tissues. Monomers like triethylene glycol dimethacrylate (TEGDMA) or 2-hydroxylethyl methacrylate (HEMA) are cytotoxic via apoptosis, induce genotoxic effects, and delay the cell cycle. Monomers also influence the response of cells of the innate immune system, inhibit specific odontoblast cell functions, or delay the odontogenic differentiation and mineralization processes in pulp-derived cells including stem cells. These observations indicate that resin monomers act as environmental stressors which inevitably disturb regulatory cellular networks through interference with signal transduction pathways. We hypothesize that an understanding of the cellular mechanisms underlying these phenomena will provide a better estimation of the consequences associated with dental therapy using composite materials, and lead to innovative therapeutic strategies and improved materials being used at tissue interfaces within the oral cavity. Current findings strongly suggest that monomers enhance the formation of reactive oxygen species (ROS), which is most likely the cause of biological reactions activated by dental composites and resin monomers. The aim of the present review manuscript is to discuss adaptive cell responses to oxidative stress caused by monomers. The particular significance of a tightly controlled network of non-enzymatic as well as enzymatic antioxidants for the regulation of cellular redox homeostasis and antioxidant defense in monomer-exposed cells will be addressed. The expression of ROS-metabolizing antioxidant enzymes like superoxide dismutase (SOD1), glutathione peroxidase (GPx1/2), and catalase in cells exposed to monomers will be discussed with particular emphasis on the role

  12. Auranofin induces apoptosis and necrosis in HeLa cells via oxidative stress and glutathione depletion.

    Science.gov (United States)

    You, Bo Ra; Shin, Hye Rim; Han, Bo Ram; Kim, Suhn Hee; Park, Woo Hyun

    2015-02-01

    Auranofin (Au), an inhibitor of thioredoxin reductase, is a known anti‑cancer drug. In the present study, the anti‑growth effect of Au on HeLa cervical cancer cells was examined in association with levels of reactive oxygen species (ROS) and glutathione (GSH). Au inhibited the growth of HeLa cells with an IC50 of ~2 µM at 24 h. This agent induced apoptosis and necrosis, accompanied by the cleavage of poly (ADP‑ribose) polymerase and loss of mitochondrial membrane potential. The pan‑caspase inhibitor, benzyloxycarbonyl‑Val‑Ala‑Asp‑fluoromethylketone, prevented apoptotic cell death and each of the assessed caspase inhibitors inhibited necrotic cell death induced by Au. With respect to the levels of ROS and GSH, Au increased intracellular O2•- in the HeLa cells and induced GSH depletion. The pan‑caspase inhibitor reduced the levels of O2•- and GSH depletion in Au‑treated HeLa cells. The antioxidant, N‑acetyl cysteine, not only attenuated apoptosis and necrosis in the Au‑treated HeLa cells, but also decreased the levels of O2•- and GSH depletion in the cells. By contrast, L‑buthionine sulfoximine, a GSH synthesis inhibitor, intensified cell death O2•- and GSH depletion in the Au‑treated HeLa cells. In conclusion, Au induced apoptosis and necrosis in HeLa cells via the induction of oxidative stress and the depletion of GSH.

  13. Copper ferrite nanoparticle-induced cytotoxicity and oxidative stress in human breast cancer MCF-7 cells.

    Science.gov (United States)

    Ahamed, Maqusood; Akhtar, Mohd Javed; Alhadlaq, Hisham A; Alshamsan, Aws

    2016-06-01

    Copper ferrite (CuFe2O4) nanoparticles (NPs) are important magnetic materials currently under research due to their applicability in nanomedicine. However, information concerning the biological interaction of copper ferrite NPs is largely lacking. In this study, we investigated the cellular response of copper ferrite NPs in human breast cancer (MCF-7) cells. Copper ferrite NPs were prepared by co-precipitation technique with the thermal effect. Prepared NPs were characterized by X-ray diffraction (XRD), field emission transmission electron microscopy (FETEM) and dynamic light scattering (DLS). Characterization data showed that copper ferrite NPs were crystalline, spherical with smooth surfaces and average diameter of 15nm. Biochemical studies showed that copper ferrite NPs induce cell viability reduction and membrane damage in MCF-7 cells and degree of induction was dose- and time-dependent. High SubG1 cell population during cell cycle progression and MMP loss with a concomitant up-regulation of caspase-3 and caspase-9 genes suggested that copper ferrite NP-induced cell death through mitochondrial pathway. Copper ferrite NP was also found to induce oxidative stress in MCF-7 cells as indicated by reactive oxygen species (ROS) generation and glutathione depletion. Cytotoxicity due to copper ferrite NPs exposure was effectively abrogated by N-acetyl-cysteine (ROS scavenger) suggesting that oxidative stress could be the plausible mechanism of copper ferrite NPs toxicity. Further studies are underway to explore the toxicity mechanisms of copper ferrite NPs in different types of human cells. This study warrants further generation of extensive biointeraction data before their application in nanomedicine.

  14. Persistent oxidative stress in human neural stem cells exposed to low fluences of charged particles.

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    Baulch, Janet E; Craver, Brianna M; Tran, Katherine K; Yu, Liping; Chmielewski, Nicole; Allen, Barrett D; Limoli, Charles L

    2015-08-01

    Exposure to the space radiation environment poses risks for a range of deleterious health effects due to the unique types of radiation encountered. Galactic cosmic rays are comprised of a spectrum of highly energetic nuclei that deposit densely ionizing tracks of damage along the particle trajectory. These tracks are distinct from those generated by the more sparsely ionizing terrestrial radiations, and define the geometric distribution of the complex cellular damage that results when charged particles traverse the tissues of the body. The exquisite radiosensitivity of multipotent neural stem and progenitor cells found within the neurogenic regions of the brain predispose the central nervous system to elevated risks for radiation induced sequelae. Here we show that human neural stem cells (hNSC) exposed to different charged particles at space relevant fluences exhibit significant and persistent oxidative stress. Radiation induced oxidative stress was found to be most dependent on total dose rather than on the linear energy transfer of the incident particle. The use of redox sensitive fluorogenic dyes possessing relative specificity for hydroxyl radicals, peroxynitrite, nitric oxide (NO) and mitochondrial superoxide confirmed that most irradiation paradigms elevated reactive oxygen and nitrogen species (ROS and RNS, respectively) in hNSC over a 1 week interval following exposure. Nitric oxide synthase (NOS) was not the major source of elevated nitric oxides, as the use of NOS inhibitors had little effect on NO dependent fluorescence. Our data provide extensive evidence for the capability of low doses of charged particles to elicit marked changes in the metabolic profile of irradiated hNSC. Radiation induced changes in redox state may render the brain more susceptible to the development of neurocognitive deficits that could affect an astronaut's ability to perform complex tasks during extended missions in deep space.

  15. Persistent oxidative stress in human neural stem cells exposed to low fluences of charged particles

    Directory of Open Access Journals (Sweden)

    Janet E. Baulch

    2015-08-01

    Full Text Available Exposure to the space radiation environment poses risks for a range of deleterious health effects due to the unique types of radiation encountered. Galactic cosmic rays are comprised of a spectrum of highly energetic nuclei that deposit densely ionizing tracks of damage along the particle trajectory. These tracks are distinct from those generated by the more sparsely ionizing terrestrial radiations, and define the geometric distribution of the complex cellular damage that results when charged particles traverse the tissues of the body. The exquisite radiosensitivity of multipotent neural stem and progenitor cells found within the neurogenic regions of the brain predispose the central nervous system to elevated risks for radiation induced sequelae. Here we show that human neural stem cells (hNSC exposed to different charged particles at space relevant fluences exhibit significant and persistent oxidative stress. Radiation induced oxidative stress was found to be most dependent on total dose rather than on the linear energy transfer of the incident particle. The use of redox sensitive fluorogenic dyes possessing relative specificity for hydroxyl radicals, peroxynitrite, nitric oxide (NO and mitochondrial superoxide confirmed that most irradiation paradigms elevated reactive oxygen and nitrogen species (ROS and RNS, respectively in hNSC over a 1 week interval following exposure. Nitric oxide synthase (NOS was not the major source of elevated nitric oxides, as the use of NOS inhibitors had little effect on NO dependent fluorescence. Our data provide extensive evidence for the capability of low doses of charged particles to elicit marked changes in the metabolic profile of irradiated hNSC. Radiation induced changes in redox state may render the brain more susceptible to the development of neurocognitive deficits that could affect an astronaut’s ability to perform complex tasks during extended missions in deep space.

  16. Oxidative stress induced Interleukin-32 mRNA expression in human bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Kudo Megumi

    2012-03-01

    Full Text Available Abstract Background Chronic obstructive pulmonary disease (COPD is characterized by airflow obstruction and persistent inflammation in the airways and lung parenchyma. Oxidative stress contributes to the pathogenesis of COPD. Interleukin (IL-32 expression has been reported to increase in the lung tissue of patients with COPD. Here, we show that IFNγ upregulated IL-32 expression and that oxidative stress augmented IFNγ-induced-IL-32 expression in airway epithelial cells. We further investigated transcriptional regulation responsible for IFNγ induced IL-32 expression in human airway epithelial cells. Methods Human bronchial epithelial (HBE cells were stimulated with H2O2 and IFNγ, and IL-32 expression was evaluated. The cell viability was confirmed by MTT assay. The intracellular signaling pathways regulating IL-32 expression were investigated by examining the regulatory effects of MAPK inhibitors and JAK inhibitor after treatment with H2O2 and IFNγ, and by using a ChIP assay to identify transcription factors (i.e. c-Jun, CREB binding to the IL-32 promoter. Promoter activity assays were conducted after mutations were introduced into binding sites of c-Jun and CREB in the IL-32 promoter. IL-32 expression was also examined in HBE cells in which the expression of either c-Jun or CREB was knocked out by siRNA of indicated transcription factors. Results There were no significant differences of cell viability among groups. After stimulation with H2O2 or IFNγ for 48 hours, IL-32 expression in HBE cells was increased by IFNγ and synergistically upregulated by the addition of H2O2. The H2O2 augmented IFNγ induced IL-32 mRNA expression was suppressed by a JNK inhibitor, but not by MEK inhibitor, p38 inhibitor, and JAK inhibitor I. Significant binding of c-Jun and CREB to the IL-32 promoter was observed in the IFNγ + H2O2 stimulated HBE cells. Introducing mutations into the c-Jun/CREB binding sites in the IL-32 promoter prominently suppressed its

  17. Regulation of mitochondrial function and endoplasmic reticulum stress by nitric oxide in pluripotent stem cells

    Science.gov (United States)

    Caballano-Infantes, Estefania; Terron-Bautista, José; Beltrán-Povea, Amparo; Cahuana, Gladys M; Soria, Bernat; Nabil, Hajji; Bedoya, Francisco J; Tejedo, Juan R

    2017-01-01

    Mitochondrial dysfunction and endoplasmic reticulum stress (ERS) are global processes that are interrelated and regulated by several stress factors. Nitric oxide (NO) is a multifunctional biomolecule with many varieties of physiological and pathological functions, such as the regulation of cytochrome c inhibition and activation of the immune response, ERS and DNA damage; these actions are dose-dependent. It has been reported that in embryonic stem cells, NO has a dual role, controlling differentiation, survival and pluripotency, but the molecular mechanisms by which it modulates these functions are not yet known. Low levels of NO maintain pluripotency and induce mitochondrial biogenesis. It is well established that NO disrupts the mitochondrial respiratory chain and causes changes in mitochondrial Ca2+ flux that induce ERS. Thus, at high concentrations, NO becomes a potential differentiation agent due to the relationship between ERS and the unfolded protein response in many differentiated cell lines. Nevertheless, many studies have demonstrated the need for physiological levels of NO for a proper ERS response. In this review, we stress the importance of the relationships between NO levels, ERS and mitochondrial dysfunction that control stem cell fate as a new approach to possible cell therapy strategies. PMID:28289506

  18. Induction of Inducible Nitric Oxide Synthase by Lipopolysaccharide and the Influences of Cell Volume Changes, Stress Hormones and Oxidative Stress on Nitric Oxide Efflux from the Perfused Liver of Air-Breathing Catfish, Heteropneustes fossilis.

    Science.gov (United States)

    Choudhury, Mahua G; Saha, Nirmalendu

    2016-01-01

    The air-breathing singhi catfish (Heteropneustes fossilis) is frequently being challenged by bacterial contaminants, and different environmental insults like osmotic, hyper-ammonia, dehydration and oxidative stresses in its natural habitats throughout the year. The main objectives of the present investigation were to determine (a) the possible induction of inducible nitric oxide synthase (iNOS) gene with enhanced production of nitric oxide (NO) by intra-peritoneal injection of lipopolysaccharide (LPS) (a bacterial endotoxin), and (b) to determine the effects of hepatic cell volume changes due to anisotonicity or by infusion of certain metabolites, stress hormones and by induction of oxidative stress on production of NO from the iNOS-induced perfused liver of singhi catfish. Intra-peritoneal injection of LPS led to induction of iNOS gene and localized tissue specific expression of iNOS enzyme with more production and accumulation of NO in different tissues of singhi catfish. Further, changes of hydration status/cell volume, caused either by anisotonicity or by infusion of certain metabolites such as glutamine plus glycine and adenosine, affected the NO production from the perfused liver of iNOS-induced singhi catfish. In general, increase of hydration status/cell swelling due to hypotonicity caused decrease, and decrease of hydration status/cell shrinkage due to hypertonicity caused increase of NO efflux from the perfused liver, thus suggesting that changes in hydration status/cell volume of hepatic cells serve as a potent modulator for regulating the NO production. Significant increase of NO efflux from the perfused liver was also observed while infusing the liver with stress hormones like epinephrine and norepinephrine, accompanied with decrease of hydration status/cell volume of hepatic cells. Further, oxidative stress, caused due to infusion of t-butyl hydroperoxide and hydrogen peroxide separately, in the perfused liver of singhi catfish, resulted in

  19. Relationships between oxidative stress markers and red blood cell characteristics in renal azotemic dogs.

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    Buranakarl, C; Trisiriroj, M; Pondeenana, S; Tungjitpeanpong, T; Jarutakanon, P; Penchome, R

    2009-04-01

    Oxidative stress parameters and erythrocyte characteristics were studied in 15 normal healthy dogs and 33 renal azotaemic dogs from Small Animal Hospital, Faculty of Veterinary Science, Chulalongkorn University. Dogs with renal azotaemia had reduced mean corpuscular volume (MCV) (PDogs with severe renal azotaemia had higher intraerythrocytic sodium contents (RBC-Na) (Pred blood cell catalase activity and glutathione and plasma malondialdehyde were unaltered while urinary malondialdehyde-creatinine ratio (U-MDA/Cr) increased significantly (Pdogs. Moreover, the U-MDA/Cr is a sensitive biochemical parameter which increased along with degree of renal dysfunction.

  20. Detection of oxidative stress biomarker-induced assembly of gold nanoparticles in retinal pigment epithelial cells

    Science.gov (United States)

    Yasmin, Z.; Lee, Y.; Maswadi, S.; Glickman, R.; Nash, K. L.

    2013-02-01

    Oxidative stress (OS) is increasingly implicated as an underlying pathogenic mechanism in a wide range of diseases, resulting from an imbalance between the production of reactive oxygen species (ROS) and the system's ability to detoxify the reactive intermediates or repair the resulting damage. ROS can be difficult to detect directly; however, they can be detected indirectly from the effects on oxidative stress biomarkers (OSB), such as glutathione (GSH), 3-nitrotyrosine, homocysteine, and cysteine. Moreover the reaction of transition metals with thiol-containing amino acids (for example GSH) oxidized by ROS can yield reactive products that accumulate with time and contribute to aging and diseases. The study of the interaction between OSB using functionalized nanoparticles (fNPs) has attracted interest because of potential applications in bio-sensors and biomedical diagnostics. A goal of the present work is to use fNPs to detect and ultimately quantitate OS in retinal pigment epithelial (RPE) cells subjected to external stressors, e.g. nonionizing (light) and ionizing (gamma) radiation. Specifically, we are investigating the assembly of gold fNPs mediated by the oxidation of GSH in irradiated RPE cells. The dynamic interparticle interactions had been characterized in previously reported work by monitoring the evolution of the surface plasmon resonance band using spectroscopic analysis (UV-VIS absorption). Here we are comparing the dynamic evolution of fNP assembly using photoacoustic spectroscopy (PAS). We expect that PAS will provide a more sensitive measure allowing these fNP sensors to measure OS in cell-based models without the artifacts limiting the use of current methods, such as fluorescent indicators.

  1. Oxidative stress activates the TRPM2-Ca(2+)-CaMKII-ROS signaling loop to induce cell death in cancer cells.

    Science.gov (United States)

    Wang, Qian; Huang, Lihong; Yue, Jianbo

    2016-12-20

    High intracellular levels of reactive oxygen species (ROS) cause oxidative stress that results in numerous pathologies, including cell death. Transient potential receptor melastatin-2 (TRPM2), a Ca(2+)-permeable cation channel, is mainly activated by intracellular adenosine diphosphate ribose (ADPR) in response to oxidative stress. Here we studied the role and mechanisms of TRPM2-mediated Ca(2+) influx on oxidative stress-induced cell death in cancer cells. We found that oxidative stress activated the TRPM2-Ca(2+)-CaMKII cascade to inhibit early autophagy induction, which ultimately led to cell death in TRPM2 expressing cancer cells. On the other hand, TRPM2 knockdown switched cells from cell death to autophagy for survival in response to oxidative stress. Moreover, we found that oxidative stress activated the TRPM2-CaMKII cascade to further induce intracellular ROS production, which led to mitochondria fragmentation and loss of mitochondrial membrane potential. In summary, our data demonstrated that oxidative stress activates the TRPM2-Ca(2+)-CaMKII-ROS signal loop to inhibit autophagy and induce cell death.

  2. Oxidative stress and age-related changes in T cells: is thalassemia a model of accelerated immune system aging?

    Science.gov (United States)

    Ghatreh-Samani, Mahdi; Esmaeili, Nafiseh; Soleimani, Masoud; Asadi-Samani, Majid; Ghatreh-Samani, Keihan; Shirzad, Hedayatolah

    2016-01-01

    Iron overload in β-thalassemia major occurs mainly due to blood transfusion, an essential treatment for β-thalassemia major patients, which results in oxidative stress. It has been thought that oxidative stress causes elevation of immune system senescent cells. Under this condition, cells normally enhance in aging, which is referred to as premature immunosenescence. Because there is no animal model for immunosenescence, most knowledge on the immunosenescence pattern is based on induction of immunosenescence. In this review, we describe iron overload and oxidative stress in β-thalassemia major patients and how they make these patients a suitable human model for immunosenescence. We also consider oxidative stress in some kinds of chronic virus infections, which induce changes in the immune system similar to β-thalassemia major. In conclusion, a therapeutic approach used to improve the immune system in such chronic virus diseases, may change the immunosenescence state and make life conditions better for β-thalassemia major patients.

  3. Hispidin derived from Phellinus linteus affords protection against acrylamide-induced oxidative stress in Caco-2 cells.

    Science.gov (United States)

    Chen, Wei; Shen, Yang; Su, Hongming; Zheng, Xiaodong

    2014-08-05

    Acrylamide (AA), a well-known toxicant, has attracted numerous attentions for its presumably carcinogenesis, neurotoxicity and cytotoxicity. Oxidative stress was considered to be associated with acrylamide cytotoxicity, but the link between oxidative stress and acrylamide cytotoxicity is still unclear. In the present study, hispidin produced from the edible fungus Phellinus linteus displayed dramatically antioxidant activities against DPPH radicals, ABTS radicals, ferric reducing and hydroxyl radicals, as well as superoxide anion radicals. Moreover, the cytoprotective effect of hispidin against AA-induced oxidative stress was verified upon Caco-2 cells according to evaluate the cell viability, intracellular ROS, mitochondrial membrane potential (MMP) and glutathione (GSH) in the presence or absence of AA (5 mM) in a dose-dependent manner. Collectively, our results demonstrated for the first time that hispidin was able to inhibit AA-induced oxidative stress, which might have implication for the dietary preventive application.

  4. Chokeberry Anthocyanin Extract as Pancreatic β-Cell Protectors in Two Models of Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Dumitriţa Rugină

    2015-01-01

    Full Text Available The aim of this study was to investigate the protective effects of a chokeberry anthocyanin extract (CAE on pancreatic β-cells (βTC3 exposed to hydrogen peroxide- (H2O2- and high glucose- (HG- induced oxidative stress conditions. In order to quantify individual anthocyanins high performance liquid chromatography (HPLC coupled to photodiode array (PDA was used. The identification of the fragment ion pattern of anthocyanins was carried out by electrospray ionization mass spectrometry (LC-ESI-MS. The results showed that physiologically achievable concentrations of CAE (1, 5, and 10 μM protect βTC3 against H2O2- and HG-induced cytotoxicity. Antioxidant enzymes such as superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPx were increased in pancreatic β-cells pretreated with CAE compared to cells exposed to the prooxidant agents. GSH levels initially reduced after exposure to H2O2 and HG were restored by pretreatment with CAE. Insulin secretion in βTC3 cells was enhanced by CAE pretreatment. CAE restored the insulin pool and diminished the intracellular reactive oxygen species level in glucose-induced stress condition in βTC3 cells. These results demonstrate that anthocyanins from CAE were biologically active, showing a secretagogue potential and an antioxidative protection of enzymatic systems, conferring protection against H2O2 and glucose toxicity in βTC3 cells.

  5. Oxidative stress induces hypomethylation of LINE-1 and hypermethylation of the RUNX3 promoter in a bladder cancer cell line.

    Science.gov (United States)

    Wongpaiboonwattana, Wikrom; Tosukhowong, Piyaratana; Dissayabutra, Thasinas; Mutirangura, Apiwat; Boonla, Chanchai

    2013-01-01

    Increased oxidative stress and changes in DNA methylation are frequently detected in bladder cancer patients. We previously demonstrated a relationship between increased oxidative stress and hypomethylation of the transposable long-interspersed nuclear element-1 (LINE-1). Promoter hypermethylation of a tumor suppressor gene, runt-related transcription factor 3 (RUNX3), may also be associated with bladder cancer genesis. In this study, we investigated changes of DNA methylation in LINE-1 and RUNX3 promoter in a bladder cancer cell (UM-UC-3) under oxidative stress conditions, stimulated by challenge with H2O2 for 72 h. Cells were pretreated with an antioxidant, tocopheryl acetate for 1 h to attenuate oxidative stress. Methylation levels of LINE-1 and RUNX3 promoter were measured by combined bisulfite restriction analysis PCR and methylation-specific PCR, respectively. Levels of LINE-1 methylation were significantly decreased in H2O2-treated cells, and reestablished after pretreated with tocopheryl acetate. Methylation of RUNX3 promoter was significantly increased in cells exposed to H2O2. In tocopheryl acetate pretreated cells, it was markedly decreased. In conclusion, hypomethylation of LINE-1 and hypermethylation of RUNX3 promoter in bladder cancer cell line was experimentally induced by reactive oxygen species (ROS). The present findings support the hypothesis that oxidative stress promotes urothelial cell carcinogenesis through modulation of DNA methylation. Our data also imply that mechanistic pathways of ROS-induced alteration of DNA methylation in a repetitive DNA element and a gene promoter might differ.

  6. Reticular dysgenesis–associated AK2 protects hematopoietic stem and progenitor cell development from oxidative stress

    Science.gov (United States)

    Rissone, Alberto; Weinacht, Katja Gabriele; la Marca, Giancarlo; Bishop, Kevin; Giocaliere, Elisa; Jagadeesh, Jayashree; Felgentreff, Kerstin; Dobbs, Kerry; Al-Herz, Waleed; Jones, Marypat; Chandrasekharappa, Settara; Kirby, Martha; Wincovitch, Stephen; Simon, Karen Lyn; Itan, Yuval; DeVine, Alex; Schlaeger, Thorsten; Schambach, Axel; Sood, Raman

    2015-01-01

    Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD. PMID:26150473

  7. Oxidative Stress Impairs Cell Death by Repressing the Nuclease Activity of Mitochondrial Endonuclease G

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    Jason L.J. Lin

    2016-07-01

    Full Text Available Endonuclease G (EndoG is a mitochondrial protein that is released from mitochondria and relocated into the nucleus to promote chromosomal DNA fragmentation during apoptosis. Here, we show that oxidative stress causes cell-death defects in C. elegans through an EndoG-mediated cell-death pathway. In response to high reactive oxygen species (ROS levels, homodimeric CPS-6—the C. elegans homolog of EndoG—is dissociated into monomers with diminished nuclease activity. Conversely, the nuclease activity of CPS-6 is enhanced, and its dimeric structure is stabilized by its interaction with the worm AIF homolog, WAH-1, which shifts to disulfide cross-linked dimers under high ROS levels. CPS-6 thus acts as a ROS sensor to regulate the life and death of cells. Modulation of the EndoG dimer conformation could present an avenue for prevention and treatment of diseases resulting from oxidative stress.

  8. Role of ALADIN in human adrenocortical cells for oxidative stress response and steroidogenesis.

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    Ramona Jühlen

    Full Text Available Triple A syndrome is caused by mutations in AAAS encoding the protein ALADIN. We investigated the role of ALADIN in the human adrenocortical cell line NCI-H295R1 by either over-expression or down-regulation of ALADIN. Our findings indicate that AAAS knock-down induces a down-regulation of genes coding for type II microsomal cytochrome P450 hydroxylases CYP17A1 and CYP21A2 and their electron donor enzyme cytochrome P450 oxidoreductase, thereby decreasing biosynthesis of precursor metabolites required for glucocorticoid and androgen production. Furthermore we demonstrate that ALADIN deficiency leads to increased susceptibility to oxidative stress and alteration in redox homeostasis after paraquat treatment. Finally, we show significantly impaired nuclear import of DNA ligase 1, aprataxin and ferritin heavy chain 1 in ALADIN knock-down cells. We conclude that down-regulating ALADIN results in decreased oxidative stress response leading to alteration in steroidogenesis, highlighting our knock-down cell model as an important in-vitro tool for studying the adrenal phenotype in triple A syndrome.

  9. Proteasome inhibitor MG-132 induces C6 glioma cell apoptosis via oxidative stress

    Institute of Scientific and Technical Information of China (English)

    Wen-hai FAN; Yi HOU; Fan-kai MENG; Xiao-fei WANG; Yi-nan LUO; Peng-fei GE

    2011-01-01

    Aim: Proteasome inhibitors have been found to suppress gtioma cell proliferation and induce apoptosis, but the mechanisms are not fully elucidated. In this study we investigated the mechanisms underlying the apoptosis induced by the proteasome inhibitor MG-132 in glioma cells.Methods: C6 glioma cells were used. MTF assay was used to analyze cell proliferation. Proteasome activity was assayed using Succi-nyI-LLVY-AMC, and intracellular ROS level was evaluated with the redox-sensitive dye DCFH-DA. Apoptosis was detected using fluores-cence and transmission electron microscopy as well as flow cytometry. The expression of apoptosis-related proteins was investigated using Western blot analysis.Results: MG-132 inhibited C6 glioma cell proliferation in a time- and dose-dependent manner (the IC value at 24 h was 18.5 μmol/L). MG-132 (18.5 μmol/L) suppressed the proteasome activity by about 70% at 3 h. It induced apoptosis via down-regulation of antiapop-totic proteins Bcl-2 and XlAP0 up-regulation of pro-apoptotic protein Bax and caspase-3, and production of cleaved C-terminal 85 kDa PARP). It also caused a more than 5-fold increase of reactive oxygen species. Tiron (1 mmol/L) effectively blocked oxidative stress induced by MG-132 (18.5 pmol/L), attenuated proliferation inhibition and apoptosis in C6 glioma cells, and reversed the expression pattern of apoptosis-related proteins.Conclusion: MG-132 induced apoptosis of C6 glioma cells via the oxidative stress.

  10. The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.

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    Frank Maus

    Full Text Available The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG2 has been downregulated by siRNA, or OPC from the NG2-knockout mouse show an increased sensitivity to oxidative stress evidenced by increased cell death. The proapoptotic protease activity of OMI/HtrA2 in the cytosol can be reduced by the interaction with NG2. Human glioma expressing high levels of NG2 are less sensitive to oxidative stress than those with lower NG2 expression and reducing NG2 expression by siRNA increases cell death in response to oxidative stress. Binding of NG2 to OMI/HtrA2 may thus help protect cells against oxidative stress-induced cell death. This interaction is likely to contribute to the high chemo- and radioresistance of glioma.

  11. Yeast NDI1 Improve Oxidative Phosphorylation Capacity and Increases Protection Against Oxidative Stress and Cell Death in Cells Carrying a Leber’s Hereditary Optic Neuropathy Mutation

    Science.gov (United States)

    Park, Jeong Soon; Li, You-fen; Bai, Yidong

    2007-01-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber’s hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH -quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast ND11 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death. PMID:17320357

  12. Yeast NDI1 improves oxidative phosphorylation capacity and increases protection against oxidative stress and cell death in cells carrying a Leber's hereditary optic neuropathy mutation.

    Science.gov (United States)

    Park, Jeong Soon; Li, You-Fen; Bai, Yidong

    2007-05-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber's hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH-quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast NDI1 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death.

  13. Effects of N-acetyl-L-cysteine on bleomycin induced oxidative stress in malignant testicular germ cell tumors.

    Science.gov (United States)

    Cort, Aysegul; Ozdemir, Evrim; Timur, Mujgan; Ozben, Tomris

    2012-12-01

    Testicular cancer is a very common cancer in males aged 15-44 years. Bleomycin is used in chemotherapy regimens in the treatment of patients having testicular germ-cell tumor. Bleomycin generates oxygen radicals, induces oxidative cleavage of DNA strand and induces apoptosis in cancer cells. There is no study in the literature investigating effects of N-Acetyl-L-Cysteine (NAC) on bleomycin-induced oxidative stress in testicular germ cell tumors. For this reason, we studied effects of NAC on oxidative stress produced in wild-type NTera-2 and p53-mutant NCCIT testis cancer cells incubated with bleomycin and compared the results with H(2)O(2) which directly produces oxidative stress. We determined protein carbonyl content, thiobarbituric acid reactive substances (TBARS), glutathione (GSH), 8-isoprostane, lipid hydroperoxide levels and total antioxidant capacity in both testicular cancer cells. Bleomycin and H(2)O(2) significantly increased 8-isoprostane, TBARS, protein carbonyl and lipid hydroperoxide levels in NTera-2 and NCCIT cells. Bleomycin and H(2)O(2) significantly decreased antioxidant capacity and GSH levels in both cell lines. Co-incubation with NAC significantly decreased lipid hydroperoxide, 8-isoprostane, protein carbonyl content and TBARS levels increased by bleomycin and H(2)O(2). NAC enhanced GSH levels and antioxidant capacity in the NTera-2 and NCCIT cells. It can be concluded that NAC diminishes oxidative stress in human testicular cancer cells induced by bleomycin and H(2)O(2).

  14. Role of CFTR in oxidative stress and suicidal death of renal cells during cisplatin-induced nephrotoxicity

    OpenAIRE

    Rubera, I.; Duranton, C; Melis, N; Cougnon, M; Mograbi, B.; Tauc, M

    2013-01-01

    The clinical use of the antineoplastic drug cisplatin is limited by its deleterious nephrotoxic side effect. Cisplatin-induced nephrotoxicity is associated with an increase in oxidative stress, leading ultimately to renal cell death and irreversible kidney dysfunction. Oxidative stress could be modified by the cystic fibrosis transmembrane conductance regulator protein (CFTR), a Cl− channel not only involved in chloride secretion but as well in glutathione (GSH) transport. Thus, we tested whe...

  15. Oxidative stress in Parkinson's disease.

    Science.gov (United States)

    Nikam, Shashikant; Nikam, Padmaja; Ahaley, S K; Sontakke, Ajit V

    2009-01-01

    Oxidative stress contributes to the cascade, leading to dopamine cell degeneration in Parkinson's disease. However, oxidative stress is intimately linked to other components of the degenerative process, such as mitochondrial dysfunction, excitotoxicity, nitric oxide toxicity and inflammation. It is therefore difficult to determine whether oxidative stress leads to or is a consequence of, these events. Oxidative stress was assessed by estimating lipid peroxidation product in the form of thiobarbituric acid reactive substances, nitric oxide in the form of nitrite & nitrate. Enzymatic antioxidants in the form of superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin and non enzymatic antioxidant vitamins e.g. vitamin E and C in either serum or plasma or erythrocyte in 40 patients of Parkinson's disease in the age group 40-80 years. Trace elements e.g. copper, zinc and selenium were also estimated. Plasma thiobarbituric acid reactive substances and nitric oxide levels were Significantly high but superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin, vitamin-E, vitamin-C, copper, zinc and selenium levels were significantly low in Parkinson's disease when compared with control subjects. Present study showed that elevated oxidative stress may be playing a role in dopaminergic neuronal loss in substentia nigra pars compacta and involved in pathogenesis of the Parkinson's disease.

  16. A Sensitive Sensor Cell Line for the Detection of Oxidative Stress Responses in Cultured Human Keratinocytes

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    Ute Hofmann

    2014-06-01

    Full Text Available In the progress of allergic and irritant contact dermatitis, chemicals that cause the generation of reactive oxygen species trigger a heat shock response in keratinocytes. In this study, an optical sensor cell line based on cultured human keratinocytes (HaCaT cells expressing green fluorescent protein (GFP under the control of the stress-inducible HSP70B’ promoter were constructed. Exposure of HaCaT sensor cells to 25 µM cadmium, a model substance for oxidative stress induction, provoked a 1.7-fold increase in total glutathione and a ~300-fold induction of transcript level of the gene coding for heat shock protein HSP70B’. An extract of Arnica montana flowers resulted in a strong induction of the HSP70B’ gene and a pronounced decrease of total glutathione in keratinocytes. The HSP70B’ promoter-based sensor cells conveniently detected cadmium-induced stress using GFP fluorescence as read-out with a limit of detection of 6 µM cadmium. In addition the sensor cells responded to exposure of cells to A. montana extract with induction of GFP fluorescence. Thus, the HaCaT sensor cells provide a means for the automated detection of the compromised redox status of keratinocytes as an early indicator of the development of human skin disorders and could be applied for the prediction of skin irritation in more complex in vitro 3D human skin models and in the development of micro-total analysis systems (µTAS that may be utilized in dermatology, toxicology, pharmacology and drug screenings.

  17. A sensitive sensor cell line for the detection of oxidative stress responses in cultured human keratinocytes.

    Science.gov (United States)

    Hofmann, Ute; Priem, Melanie; Bartzsch, Christine; Winckler, Thomas; Feller, Karl-Heinz

    2014-06-25

    In the progress of allergic and irritant contact dermatitis, chemicals that cause the generation of reactive oxygen species trigger a heat shock response in keratinocytes. In this study, an optical sensor cell line based on cultured human keratinocytes (HaCaT cells) expressing green fluorescent protein (GFP) under the control of the stress-inducible HSP70B' promoter were constructed. Exposure of HaCaT sensor cells to 25 µM cadmium, a model substance for oxidative stress induction, provoked a 1.7-fold increase in total glutathione and a ~300-fold induction of transcript level of the gene coding for heat shock protein HSP70B'. An extract of Arnica montana flowers resulted in a strong induction of the HSP70B' gene and a pronounced decrease of total glutathione in keratinocytes. The HSP70B' promoter-based sensor cells conveniently detected cadmium-induced stress using GFP fluorescence as read-out with a limit of detection of 6 µM cadmium. In addition the sensor cells responded to exposure of cells to A. montana extract with induction of GFP fluorescence. Thus, the HaCaT sensor cells provide a means for the automated detection of the compromised redox status of keratinocytes as an early indicator of the development of human skin disorders and could be applied for the prediction of skin irritation in more complex in vitro 3D human skin models and in the development of micro-total analysis systems (µTAS) that may be utilized in dermatology, toxicology, pharmacology and drug screenings.

  18. β-carotene treatment alters the cellular death process in oxidative stress-induced K562 cells.

    Science.gov (United States)

    Akçakaya, Handan; Tok, Sabiha; Dal, Fulya; Cinar, Suzan Adin; Nurten, Rustem

    2017-03-01

    Oxidizing agents (e.g., H2 O2 ) cause structural and functional disruptions of molecules by affecting lipids, proteins, and nucleic acids. As a result, cellular mechanisms related to disrupted macro molecules are affected and cell death is induced. Oxidative damage can be prevented at a certain point by antioxidants or the damage can be reversed. In this work, we studied the cellular response against oxidative stress induced by H2 O2 and antioxidant-oxidant (β-carotene-H2 O2 ) interactions in terms of time, concentration, and treatment method (pre-, co-, and post) in K562 cells. We showed that co- or post-treatment with β-carotene did not protect cells from the damage of oxidative stress furthermore co- and post-β-carotene-treated oxidative stress induced cells showed similar results with only H2 O2 treated cells. However, β-carotene pre-treatment prevented oxidative damage induced by H2 O2 at concentrations lower than 1,000 μM compared with only H2 O2 -treated and co- and post-β-carotene-treated oxidative stress-induced cells in terms of studied cellular parameters (mitochondrial membrane potential [Δψm ], cell cycle and apoptosis). Prevention effect of β-carotene pre-treatment was lost at concentrations higher than 1,000 μM H2 O2 (2-10 mM). These findings suggest that β-carotene pre-treatment alters the effects of oxidative damage induced by H2 O2 and cell death processes in K562 cells.

  19. Low oxygen alters mitochondrial function and response to oxidative stress in human neural progenitor cells

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    Yury M. Lages

    2015-12-01

    Full Text Available Oxygen concentration should be carefully regulated in all living tissues, beginning at the early embryonic stages. Unbalances in oxygen regulation can lead to cell death and disease. However, to date, few studies have investigated the consequences of variations in oxygen levels for fetal-like cells. Therefore, in the present work, human neural progenitor cells (NPCs derived from pluripotent stem cells grown in 3% oxygen (v/v were compared with NPCs cultured in 21% (v/v oxygen. Low oxygen concentrations altered the mitochondrial content and oxidative functions of the cells, which led to improved ATP production, while reducing generation of reactive oxygen species (ROS. NPCs cultured in both conditions showed no differences in proliferation and glucose metabolism. Furthermore, antioxidant enzymatic activity was not altered in NPCs cultured in 3% oxygen under normal conditions, however, when exposed to external agents known to induce oxidative stress, greater susceptibility to DNA damage was observed. Our findings indicate that the management of oxygen levels should be considered for in vitro models of neuronal development and drug screening.

  20. Oxidative stress and hypertension.

    Science.gov (United States)

    Harrison, David G; Gongora, Maria Carolina

    2009-05-01

    This review has summarized some of the data supporting a role of ROS and oxidant stress in the genesis of hypertension. There is evidence that hypertensive stimuli, such as high salt and angiotensin II, promote the production of ROS in the brain, the kidney, and the vasculature and that each of these sites contributes either to hypertension or to the untoward sequelae of this disease. Although the NADPH oxidase in these various organs is a predominant source, other enzymes likely contribute to ROS production and signaling in these tissues. A major clinical challenge is that the routinely used antioxidants are ineffective in preventing or treating cardiovascular disease and hypertension. This is likely because these drugs are either ineffective or act in a non-targeted fashion, such that they remove not only injurious ROS Fig. 5. Proposed role of T cells in the genesis of hypertension and the role of the NADPH oxidase in multiple cells/organs in modulating this effect. In this scenario, angiotensin II stimulates an NADPH oxidase in the CVOs of the brain, increasing sympathetic outflow. Sympathetic nerve terminals in lymph nodes activate T cells, and angiotensin II also directly activates T cells. These stimuli also activate expression of homing signals in the vessel and likely the kidney, which attract T cells to these organs. T cells release cytokines that stimulate the vessel and kidney NADPH oxidases, promoting vasoconstriction and sodium retention. SFO, subfornical organ. 630 Harrison & Gongora but also those involved in normal cell signaling. A potentially important and relatively new direction is the concept that inflammatory cells such as T cells contribute to hypertension. Future studies are needed to understand the interaction of T cells with the CNS, the kidney, and the vasculature and how this might be interrupted to provide therapeutic benefit.

  1. Dexmedetomidine Attenuates Oxidative Stress Induced Lung Alveolar Epithelial Cell Apoptosis In Vitro

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    Jian Cui

    2015-01-01

    Full Text Available Background. Oxidative stress plays a pivotal role in the lung injuries of critical ill patients. This study investigates the protection conferred by α2 adrenoceptor agonist dexmedetomidine (Dex from lung alveolar epithelial cell injury induced by hydrogen peroxide (H2O2 and the underlying mechanisms. Methods. The lung alveolar epithelial cell line, A549, was cultured and then treated with 500 μM H2O2 with or without Dex (1 nM or Dex in combination with atipamezole (10 nM, an antagonist of α2 receptors. Their effect on mitochondrial membrane potential (Δψm, reactive oxygen species (ROS, and the cell cycle was assessed by flow cytometry. Cleaved-caspases 3 and 9, BAX, Bcl-2, phospho-mTOR (p-mTOR, ERK1/2, and E-cadherin expression were also determined with immunocytochemistry. Results. Upregulation of cleaved-caspases 3 and 9 and BAX and downregulation of Bcl-2, p-mTOR, and E-cadherin were found following H2O2 treatment, and all of these were reversed by Dex. Dex also prevented the ROS generation, cytochrome C release, and cell cycle arrest induced by H2O2. The effects of Dex were partially reversed by atipamezole. Conclusion. Our study demonstrated that Dex protected lung alveolar epithelial cells from apoptotic injury, cell cycle arrest, and loss of cell adhesion induced by H2O2 through enhancing the cell survival and proliferation.

  2. Severity of oxidative stress generates different mechanisms of endothelial cell death.

    Science.gov (United States)

    Burlacu, A; Jinga, V; Gafencu, A V; Simionescu, M

    2001-12-01

    The role of reactive oxygen species (ROS) in the pathogenesis of vascular diseases is well established, but few data exist on the mechanisms by which ROS induce endothelial cell (EC) death. We examined the conditions and the mechanisms by which oxidative stress induces EC death, using cultured confluent bovine aortic ECs exposed for 30 min to different concentrations of hydroxyl radicals (HO*) generated by hydrogen peroxide (H(2)O(2)) in the presence of 100 microM ferrous sulfate (FeSO(4)). Cell viability assays, Hoechst DNA staining, TUNEL (TDT-mediated dUTP-biotin nick end-labeling) analysis, agarose gel electrophoresis and annexin V assay were used to determine the effect of HO* on the viability of ECs, and to distinguish between apoptosis and necrosis. The results showed that at concentrations of up to 0.1 mM H(2)O(2)/FeSO(4), the large majority of cells are viable, except for approximately 12.5% death, which occurs by apoptosis. At a concentration of 0.2 mM H(2)O(2), the cell viability is reduced to 66%, while EC apoptosis remained at comparable values (14%). At high oxidative stress (0.5 mM H(2)O(2)), the cell viability was drastically reduced (approximately 39%), and the prevalent form of death was necrosis; apoptosis accounted for only approximately 17%. Together, these data indicate that: (1) HO* induce EC death either by apoptosis or necrosis and (2) the mechanisms of EC death differ as a function of the concentration of HO. Thus, the same insult can cause apoptosis and/or necrosis, as a function of the intensity rather than the nature of the insult.

  3. Protective effect of polyphenols from Glycyrrhiza glabra against oxidative stress in Caco-2 cells.

    Science.gov (United States)

    D'Angelo, Stefania; Morana, Alessandra; Salvatore, Anna; Zappia, Vincenzo; Galletti, Patrizia

    2009-12-01

    In the present article, we have investigated the antioxidant properties of methanolic liquorice polyphenol extracts (LPE(s)). Polyphenol extraction was performed with 60% and 100% methanol. Analysis of LPE(s) by thin-layer chromatography revealed that a higher amount of polyphenols was recovered by extraction with 60% methanol. Antioxidant activity measurement of the reducing power, scavenging effect on 2,2'-diphenyl-1-picrylhydrazyl free radical, and hydrogen peroxide scavenging capability have been taken as the parameters for assessment of antioxidant potential of LPE(s). Results have been compared with both natural and synthetic antioxidants. All experimental data have indicated that LPE(s) possess strong antioxidant power proportional to their o-diphenolic and total polyphenolic content, independently from the assay used. Therefore, the LPE(s) antioxidant property was examined against the cytotoxic effects of reactive oxygen species in human colon carcinoma cells. Pretreatment of Caco-2 cells with liquorice polyphenolic extracts provided a remarkable protection against oxidative damage induced by H(2)O(2). The highest oxidative stress protection (72% of cell vitality) was measured in cells pretreated with 0.54 mM polyphenols. This effect seems to be associated to the antioxidant activity of liquorice polyphenolic compounds. Our data suggest that polyphenols from Glycyrrhiza glabra could exert a beneficial action in the prevention of intestinal pathologies related to production of reactive oxygen species.

  4. Silica Nanoparticles Induce Oxidative Stress and Autophagy but Not Apoptosis in the MRC-5 Cell Line

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    Sorina Nicoleta Petrache Voicu

    2015-12-01

    Full Text Available This study evaluated the in vitro effects of 62.5 µg/mL silica nanoparticles (SiO2 NPs on MRC-5 human lung fibroblast cells for 24, 48 and 72 h. The nanoparticles’ morphology, composition, and structure were investigated using high resolution transmission electron microscopy, selected area electron diffraction and X-ray diffraction. Our study showed a decreased cell viability and the induction of cellular oxidative stress as evidenced by an increased level of reactive oxygen species (ROS, carbonyl groups, and advanced oxidation protein products after 24, 48, and 72 h, as well as a decreased concentration of glutathione (GSH and protein sulfhydryl groups. The protein expression of Hsp27, Hsp60, and Hsp90 decreased at all time intervals, while the level of protein Hsp70 remained unchanged during the exposure. Similarly, the expression of p53, MDM2 and Bcl-2 was significantly decreased for all time intervals, while the expression of Bax, a marker for apoptosis, was insignificantly downregulated. These results correlated with the increase of pro-caspase 3 expression. The role of autophagy in cellular response to SiO2 NPs was demonstrated by a fluorescence-labeled method and by an increased level of LC3-II/LC3-I ratio. Taken together, our data suggested that SiO2 NPs induced ROS-mediated autophagy in MRC-5 cells as a possible mechanism of cell survival.

  5. Emulsions Made of Oils from Seeds of GM Flax Protect V79 Cells against Oxidative Stress

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    Katarzyna Skorkowska-Telichowska

    2016-01-01

    Full Text Available Polyunsaturated fatty acids, sterols, and hydrophilic phenolic compounds are components of flax oil that act as antioxidants. We investigated the impact of flax oil from transgenic flax in the form of emulsions on stressed Chinese hamster pulmonary fibroblasts. We found that the emulsions protect V79 cells against the H2O2 and the effect is dose dependent. They reduced the level of intracellular reactive oxygen species and protected genomic DNA against damage. The rate of cell proliferation increased upon treatment with the emulsions at a low concentration, while at a high concentration it decreased significantly, accompanied by increased frequency of apoptotic cell death. Expression analysis of selected genes revealed the upregulatory impact of the emulsions on the histones, acetylases, and deacetylases. Expression of apoptotic, proinflammatory, and anti-inflammatory genes was also altered. It is thus suggested that flax oil emulsions might be useful as a basis for biomedical products that actively protect cells against inflammation and degeneration. The beneficial effect on fibroblast resistance to oxidative damage was superior in the emulsion made of oil from transgenic plants which was correlated with the quantity of antioxidants and squalene. The emulsions from transgenic flax are promising candidates for skin protection against oxidative damage.

  6. Expression of estrogen receptor α in human breast cancer cells regulates mitochondrial oxidative stress under simulated microgravity

    Science.gov (United States)

    Zheng, Hong-xia; Tian, Wei-ming; Yan, Hong-ji; Jiang, Hua-dong; Liu, Shan-shan; Yue, Lei; Han, Fang; Wei, Li-jun; Chen, Xiong-biao; Li, Yu

    2012-05-01

    This study investigated intracellular oxidative stress and its underlying mechanisms in a rotary cell culture system used to achieve a simulated microgravity (SMG) environment. Experiments were conducted with human breast cancer cell lines MCF-7 (an estrogen receptor (ER) α positive cell line) and MDA-MB-231 (an ERα negative cell line) encapsulated in alginate/collagen carriers. After 48 h, SMG led to oxidative stress and DNA damage in the MDA-MB-231 cells but a significant increase in mitochondrial activity and minimal DNA damage in the MCF-7 cells. The activity of superoxide dismutase (SOD) significantly increased in the MCF-7 cells and decreased in MDA-MB-231 cells in the SMG environment compared with a standard gravity control. Moreover, SMG promoted expression of ERα and protein kinase C (PKC) epsilon in MCF-7 cells treated with PKC inhibitor Gö6983. Overall, exposure to SMG increased mitochondrial activity in ERα positive cells but induced cellular oxidative damage in ERα negative cells. Thus, ERα may play an important role in protecting cells from oxidative stress damage under simulated microgravity.

  7. Dexamethasone acts as a radiosensitizer in three astrocytoma cell lines via oxidative stress

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    Sylvia Ortega-Martínez

    2015-08-01

    Full Text Available Glucocorticoids (GCs, which act on stress pathways, are well-established in the co-treatment of different kinds of tumors; however, the underlying mechanisms by which GCs act are not yet well elucidated. As such, this work investigates the role of glucocorticoids, specifically dexamethasone (DEXA, in the processes referred to as DNA damage and DNA damage response (DDR, establishing a new approach in three astrocytomas cell lines (CT2A, APP.PS1 L.1 and APP.PS1 L.3. The results show that DEXA administration increased the basal levels of gamma-H2AX foci, keeping them higher 4 h after irradiation (IR of the cells, compared to untreated cells. This means that DEXA might cause increased radiosensitivity in these cell lines. On the other hand, DEXA did not have an apparent effect on the formation and disappearance of the 53BP1 foci. Furthermore, it was found that DEXA administered 2 h before IR led to a radical change in DNA repair kinetics, even DEXA does not affect cell cycle. It is important to highlight that DEXA produced cell death in these cell lines compared to untreated cells. Finally and most important, the high levels of gamma-H2AX could be reversed by administration of ascorbic acid, a potent blocker of reactive oxygen species, suggesting that DEXA acts by causing DNA damage via oxidative stress. These exiting findings suggest that DEXA might promote radiosensitivity in brain tumors, specifically in astrocytoma-like tumors.

  8. Relief of delayed oxidative stress by ascorbic acid can suppress radiation-induced cellular senescence in mammalian fibroblast cells.

    Science.gov (United States)

    Kobashigawa, Shinko; Kashino, Genro; Mori, Hiromu; Watanabe, Masami

    2015-03-01

    Ionizing radiation-induced cellular senescence is thought to be caused by nuclear DNA damage that cannot be repaired. However, here we found that radiation induces delayed increase of intracellular oxidative stress after irradiation. We investigated whether the relief of delayed oxidative stress by ascorbic acid would suppress the radiation-induced cellular senescence in Syrian golden hamster embryo (SHE) cells. We observed that the level of oxidative stress was drastically increased soon after irradiation, then declined to the level in non-irradiated cells, and increased again with a peak on day 3 after irradiation. We found that the inductions of cellular senescence after X-irradiation were reduced along with suppression of the delayed induction of oxidative stress by treatment with ascorbic acid, but not when oxidative stress occurred immediately after irradiation. Moreover, treatment of ascorbic acid inhibited p53 accumulation at 3 days after irradiation. Our data suggested a delayed increase of intracellular oxidative stress levels plays an important role in the process of radiation-induced cellular senescence by p53 accumulation.

  9. Mercury induces proliferation and reduces cell size in vascular smooth muscle cells through MAPK, oxidative stress and cyclooxygenase-2 pathways

    Energy Technology Data Exchange (ETDEWEB)

    Aguado, Andrea; Galán, María; Zhenyukh, Olha; Wiggers, Giulia A.; Roque, Fernanda R. [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); Redondo, Santiago [Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Peçanha, Franck [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); Martín, Angela [Departamento de Bioquímica, Fisiología y Genética Molecular, Universidad Rey Juan Carlos, 28922, Alcorcón (Spain); Fortuño, Ana [Área de Ciencias Cardiovasculares, Centro de Investigación Médica Aplicada, Universidad de Navarra, 31008, Pamplona (Spain); Cachofeiro, Victoria [Departamento de Fisiología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Tejerina, Teresa [Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); and others

    2013-04-15

    Mercury exposure is known to increase cardiovascular risk but the underlying cellular mechanisms remain undetermined. We analyzed whether chronic exposure to HgCl{sub 2} affects vascular structure and the functional properties of vascular smooth muscle cells (VSMC) through oxidative stress/cyclooxygenase-2 dependent pathways. Mesenteric resistance arteries and aortas from Wistar rats treated with HgCl{sub 2} (first dose 4.6 mg kg{sup −1}, subsequent doses 0.07 mg kg{sup −1} day{sup −1}, 30 days) and cultured aortic VSMC stimulated with HgCl{sub 2} (0.05–5 μg/ml) were used. Treatment of rats with HgCl{sub 2} decreased wall thickness of the resistance and conductance vasculature, increased the number of SMC within the media and decreased SMC nucleus size. In VSMCs, exposure to HgCl{sub 2}: 1) induced a proliferative response and a reduction in cell size; 2) increased superoxide anion production, NADPH oxidase activity, gene and/or protein levels of the NADPH oxidase subunit NOX-1, the EC- and Mn-superoxide dismutases and cyclooxygenase-2 (COX-2); 3) induced activation of ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized the proliferative response and the altered cell size induced by HgCl{sub 2}. Blockade of ERK1/2 and p38 signaling pathways abolished the HgCl{sub 2}-induced Nox1 and COX-2 expression and normalized the alterations induced by mercury in cell proliferation and size. In conclusion, long exposure of VSMC to low doses of mercury activates MAPK signaling pathways that result in activation of inflammatory proteins such as NADPH oxidase and COX-2 that in turn induce proliferation of VSMC and changes in cell size. These findings offer further evidence that mercury might be considered an environmental risk factor for cardiovascular disease. - Highlights: ► Chronic HgCl{sub 2} exposure induces vascular remodeling. ► HgCl{sub 2} induces proliferation and decreased cell size in vascular smooth muscle cells. ► HgCl{sub 2} induces

  10. Rapamycin Inhibits ALDH Activity, Resistance to Oxidative Stress, and Metastatic Potential in Murine Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Xiaodong Mu

    2013-01-01

    Full Text Available Osteosarcoma (OS is the most common primary malignancy of bone. Mortality is determined by the presence of metastatic disease, but little is known regarding the biochemical events that drive metastases. Two murine OS cell lines, K7M2 and K12, are related but differ significantly in their metastatic potentials: K7M2 is highly metastatic whereas K12 displays much less metastatic potential. Using this experimental system, the mammalian target of rapamycin (mTOR pathway has been implicated in OS metastasis. We also discovered that aldehyde dehydrogenase (ALDH, a stem cell marker activity is higher in K7M2 cells than K12 cells. Rapamycin treatment reduces the expression and enzymatic activity of ALDH in K7M2 cells. ALDH inhibition renders these cells more susceptible to apoptotic death when exposed to oxidative stress. Furthermore, rapamycin treatment reduces bone morphogenetic protein-2 (BMP2 and vascular endothelial growth factor (VEGF gene expression and inhibits K7M2 proliferation, migration, and invasion in vitro. Inhibition of ALDH with disulfiram correlated with decreased mTOR expression and activity. In conclusion, we provide evidence for interaction between mTOR activity, ALDH activity, and metastatic potential in murine OS cells. Our work suggests that mTOR and ALDH are therapeutic targets for the treatment and prevention of OS metastasis.

  11. Oxidative Stress, Bone Marrow Failure, and Genome Instability in Hematopoietic Stem Cells

    Directory of Open Access Journals (Sweden)

    Christine Richardson

    2015-01-01

    Full Text Available Reactive oxygen species (ROS can be generated by defective endogenous reduction of oxygen by cellular enzymes or in the mitochondrial respiratory pathway, as well as by exogenous exposure to UV or environmental damaging agents. Regulation of intracellular ROS levels is critical since increases above normal concentrations lead to oxidative stress and DNA damage. A growing body of evidence indicates that the inability to regulate high levels of ROS leading to alteration of cellular homeostasis or defective repair of ROS-induced damage lies at the root of diseases characterized by both neurodegeneration and bone marrow failure as well as cancer. That these diseases may be reflective of the dynamic ability of cells to respond to ROS through developmental stages and aging lies in the similarities between phenotypes at the cellular level. This review summarizes work linking the ability to regulate intracellular ROS to the hematopoietic stem cell phenotype, aging, and disease.

  12. Stem cell factor (SCF) protects osteoblasts from oxidative stress through activating c-Kit-Akt signaling

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lei [Department of Orthopedics, Changzhou Wujin People’s Hospital-South Division, Affiliated Hospital of Jiangsu University, Changzhou (China); Wu, Zhong [Department of Orthopedics, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Yin, Gang; Liu, Haifeng; Guan, Xiaojun; Zhao, Xiaoqiang [Department of Orthopedics, Changzhou Wujin People’s Hospital-South Division, Affiliated Hospital of Jiangsu University, Changzhou (China); Wang, Jianguang, E-mail: jianguangwang@163.com [Department of Orthopedics, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Jianguo, E-mail: gehujianguo68@163.com [Department of Orthopedics, Changzhou Wujin People’s Hospital-South Division, Affiliated Hospital of Jiangsu University, Changzhou (China)

    2014-12-12

    Highlights: • SCF receptor c-Kit is functionally expressed in primary and transformed osteoblasts. • SCF protects primary and transformed osteoblasts from H{sub 2}O{sub 2}. • SCF activation of c-Kit in osteoblasts, required for its cyto-protective effects. • c-Kit mediates SCF-induced Akt activation in cultured osteoblasts. • Akt activation is required for SCF-regulated cyto-protective effects in osteoblasts. - Abstract: Osteoblasts regulate bone formation and remodeling, and are main target cells of oxidative stress in the progression of osteonecrosis. The stem cell factor (SCF)-c-Kit pathway plays important roles in the proliferation, differentiation and survival in a range of cell types, but little is known about its functions in osteoblasts. In this study, we found that c-Kit is functionally expressed in both osteoblastic-like MC3T3-E1 cells and primary murine osteoblasts. Its ligand SCF exerted significant cyto-protective effects against hydrogen peroxide (H{sub 2}O{sub 2}). SCF activated its receptor c-Kit in osteoblasts, which was required for its cyto-protective effects against H{sub 2}O{sub 2}. Pharmacological inhibition (by Imatinib and Dasatinib) or shRNA-mediated knockdown of c-Kit thus inhibited SCF-mediated osteoblast protection. Further investigations showed that protection by SCF against H{sub 2}O{sub 2} was mediated via activation of c-Kit-dependent Akt pathway. Inhibition of Akt activation, through pharmacological or genetic means, suppressed SCF-mediated anti-H{sub 2}O{sub 2} activity in osteoblasts. In summary, we have identified a new SCF-c-Kit-Akt physiologic pathway that protects osteoblasts from H{sub 2}O{sub 2}-induced damages, and might minimize the risk of osteonecrosis caused by oxidative stress.

  13. Control of Oxidative Stress and Generation of Induced Pluripotent Stem Cell-like Cells by Jun Dimerization Protein 2

    Energy Technology Data Exchange (ETDEWEB)

    Chiou, Shyh-Shin, E-mail: chiouss@kmu.edu.tw [Division of Hematology-Oncology, Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan (China); Department of Pediatrics, Faculty of Medicine, School of Medicine, Kaohsiung Medical University, 807 Kaohsiung 807, Taiwan (China); Wang, Sophie Sheng-Wen; Wu, Deng-Chyang [Department of Gastroenterology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan (China); Lin, Ying-Chu [School of Dentistry, College of Dentistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Kao, Li-Pin [Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 807 Kaohsiung 807, Taiwan (China)

    2013-07-26

    We report here that the Jun dimerization protein 2 (JDP2) plays a critical role as a cofactor for the transcription factors nuclear factor-erythroid 2-related factor 2 (Nrf2) and MafK in the regulation of the antioxidants and production of reactive oxygen species (ROS). JDP2 associates with Nrf2 and MafK (Nrf2-MafK) to increase the transcription of antioxidant response element-dependent genes. Oxidative-stress-inducing reagent led to an increase in the intracellular accumulation of ROS and cell proliferation in Jdp2 knock-out mouse embryonic fibroblasts. In Jdp2-Cre mice mated with reporter mice, the expression of JDP2 was restricted to granule cells in the brain cerebellum. The induced pluripotent stem cells (iPSC)-like cells were generated from DAOY medulloblastoma cell by introduction of JDP2, and the defined factor OCT4. iPSC-like cells expressed stem cell-like characteristics including alkaline phosphatase activity and some stem cell markers. However, such iPSC-like cells also proliferated rapidly, became neoplastic, and potentiated cell malignancy at a later stage in SCID mice. This study suggests that medulloblastoma cells can be reprogrammed successfully by JDP2 and OCT4 to become iPSC-like cells. These cells will be helpful for studying the generation of cancer stem cells and ROS homeostasis.

  14. Control of Oxidative Stress and Generation of Induced Pluripotent Stem Cell-like Cells by Jun Dimerization Protein 2

    Directory of Open Access Journals (Sweden)

    Naoto Yamaguchi

    2013-07-01

    Full Text Available We report here that the Jun dimerization protein 2 (JDP2 plays a critical role as a cofactor for the transcription factors nuclear factor-erythroid 2-related factor 2 (Nrf2 and MafK in the regulation of the antioxidants and production of reactive oxygen species (ROS. JDP2 associates with Nrf2 and MafK (Nrf2-MafK to increase the transcription of antioxidant response element-dependent genes. Oxidative-stress-inducing reagent led to an increase in the intracellular accumulation of ROS and cell proliferation in Jdp2 knock-out mouse embryonic fibroblasts. In Jdp2-Cre mice mated with reporter mice, the expression of JDP2 was restricted to granule cells in the brain cerebellum. The induced pluripotent stem cells (iPSC-like cells were generated from DAOY medulloblastoma cell by introduction of JDP2, and the defined factor OCT4. iPSC-like cells expressed stem cell-like characteristics including alkaline phosphatase activity and some stem cell markers. However, such iPSC-like cells also proliferated rapidly, became neoplastic, and potentiated cell malignancy at a later stage in SCID mice. This study suggests that medulloblastoma cells can be reprogrammed successfully by JDP2 and OCT4 to become iPSC-like cells. These cells will be helpful for studying the generation of cancer stem cells and ROS homeostasis.

  15. Carbamylated low-density lipoprotein induces oxidative stress and accelerated senescence in human endothelial progenitor cells.

    Science.gov (United States)

    Carracedo, Julia; Merino, Ana; Briceño, Carolina; Soriano, Sagrario; Buendía, Paula; Calleros, Laura; Rodriguez, Mariano; Martín-Malo, Alejandro; Aljama, Pedro; Ramírez, Rafael

    2011-04-01

    Carbamylated low-density lipoprotein (cLDL) plays a role in atherosclerosis. In this study we evaluate the effect of uremia on LDL carbamylation and the effect of cLDL and oxidized LDL (oxLDL; 200 μg/ml) on number, function, and genomic stability of endothelial progenitor cells (EPCs) obtained from healthy volunteers. cLDL was generated after incubation of native LDL (nLDL) with uremic serum from patients with chronic kidney disease (CKD) stages 2-4. Oxidative stress was measured by flow cytometry and fluorescent microscopy, mitochondrial depolarization by flow cytometry, senescence by β-galactosidase activity and telomere length, and DNA damage by phosphorylated histone H2AX (γH2AX). The percentage of cLDL by uremic serum was related to the severity of CKD. Compared with nLDL, cLDL induced an increase in oxidative stress (62±5 vs. 8±3%, P<0.001) and cells with mitochondrial depolarization (73±7 vs. 9±5%, P<0.001), and a decrease in EPC proliferation and angiogenesis. cLDL also induced accelerated senescence (73±16 vs. 12±9%, P<0.001), which was associated with a decrease in the expression of γH2AX (62±9 vs. 5±3%, P<0.001). The degree of injury induced by cLDL was comparable to that observed with oxLDL. This study supports the hypothesis that cLDL triggers genomic damage in EPCs, resulting in premature senescence. We can, therefore, hypothesize that EPCs injury by cLDL contributes to an increase in atherosclerotic disease in CKD.

  16. Chemically-induced oxidative stress increases the vulnerability of PC12 cells to rotenone-induced toxicity

    NARCIS (Netherlands)

    de Groot, Martje W G D M; Westerink, Remco H S

    2014-01-01

    In vitro models, including the widely used PC12 cell line, can increase insight into cellular and molecular mechanisms underlying neurodegenerative processes. An important determinant for the vulnerability of cells for chemical insults may be the endogenous level of oxidative stress. To test this hy

  17. Oxidative stress and hepatitis C virus

    OpenAIRE

    2013-01-01

    The disproportionate imbalance between the systemic manifestation of reactive oxygen species and body’s ability to detoxify the reactive intermediates is referred to as oxidative stress. Several biological processes as well as infectious agents, physiological or environmental stress, and perturbed antioxidant response can promote oxidative stress. Oxidative stress usually happens when cells are exposed to more electrically charged reactive oxygen species (ROS) such as H2O2 or O2-. The cells’ ...

  18. Dichloromethane extracts of propolis protect cell from oxygen-glucose deprivation-induced oxidative stress via reducing apoptosis

    Directory of Open Access Journals (Sweden)

    Li-Ping Sun

    2016-06-01

    Full Text Available Background: Bee propolis, a mixture of the secretion from bee tongue gland and wax gland, was collected from the tree bud and barked by bees. The components were rich in terpenes, phenolics, and flavonoids, and had anti-cancer, anti-bacterial, anti-inflammatory, hepatoprotective, and neuroprotection abilities. However, the potential anti-oxidative stress of propolis was not well documented. This study aimed to study the protective effect of propolis on high-incident nonfatal diseases, such as stroke and cerebral infarction caused by ischemia. Objective: Oxidative stress caused by acute stroke results in inflammation and injury followed by cell damage and apoptosis. Clarification of the anti-oxidative stress effect of propolis may contribute to stroke prevention and damage reduction. Design: Propolis was separated and purified into 70% ethanol and dichloromethane extracts systematically. The fraction three (Fr.3 of dichloromethane was further separated into pinocembrin, pinobanksin, pinobanksin-3-acetate, chrysin, and galangin by chromatography. Compounds extracted from propolis were tested for cell-protection effects in an oxygen-glucose deprivation (OGD N2a cell model. MTT assay, oxidative stress markers measurement, flow cytometry, and QPCR were used to evaluate cell viability and apoptosis. Results: All compounds, especially pinocembrin and galangin, enhanced cell viability in OGD-treated N2a cells. In addition, anti-oxidative enzymes were elevated and cellular Ca2+ was reduced. They also had extreme anti-apoptosis effects by up-regulating the expression of Bcl-2 mRNA and down-regulating caspase-3 and Bax expression. Taken together, propolis had anti-oxidative effects on stress and protected cells from damage. Conclusion: The anti-oxidative effect of propolis can be applied to daily food supplements and may benefit stroke patients.

  19. Cytotoxicity, oxidative stress and genotoxicity induced by glass fibers on human alveolar epithelial cell line A549.

    Science.gov (United States)

    Rapisarda, Venerando; Loreto, Carla; Ledda, Caterina; Musumeci, Giuseppe; Bracci, Massimo; Santarelli, Lory; Renis, Marcella; Ferrante, Margherita; Cardile, Venera

    2015-04-01

    Man-made vitreous fibers have been widely used as insulation material as asbestos substitutes; however their morphology and composition raises concerns. In 1988 the International Agency for Research on Cancer classified fiberglass, rock wool, slag wool, and ceramic fibers as Group 2B, i.e. possibly carcinogenic to humans. In 2002 it reassigned fiberglass, rock and slag wool, and continuous glass filaments to Group 3, not classifiable as carcinogenic to humans. The aim of this study was to verify the cytotoxic and genotoxic effects and oxidative stress production induced by in vitro exposure of human alveolar epithelial cells A549 to glass fibers with a predominant diameter 5 μm (93%). A549 cells were incubated with 5, 50, or 100 μg/ml (2.1, 21, and 42 μg/cm(2), respectively) of glass fibers for 72 h. Cytotoxicity and DNA damage were tested by the MTT and the Comet assay, respectively. Oxidative stress was determined by measuring inducible nitric oxide synthase (iNOS) expression by Western blotting, production of nitric oxide (NO) with Griess reagent, and concentration of reactive oxygen species by fluorescent quantitative analysis with 2',7'-dichlorofluorescein-diacetate (DCFH-DA). The results showed that glass fiber exposure significantly reduced cell viability and increased DNA damage and oxidative stress production in a concentration-dependent manner, demonstrating that glass fibers exert cytotoxic and genotoxic effects related to increased oxidative stress on the human alveolar cell line A549.

  20. SIRT1 sensitizes hepatocellular carcinoma cells expressing hepatitis B virus X protein to oxidative stress-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Srisuttee, Ratakorn [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Koh, Sang Seok [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Malilas, Waraporn; Moon, Jeong; Cho, Il-Rae [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Jhun, Byung Hak [Department of Applied Nanoscience, Pusan National University, Busan 609-735 (Korea, Republic of); Horio, Yoshiyuki [Department of Pharmacology, Sapporo Medical University, Sapporo 060-8556 (Japan); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer Up-regulation of SIRT1 protein and activity sensitizes Hep3B-HBX cells to oxidative stress-induced apoptosis. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for oxidation-induced apoptosis. Black-Right-Pointing-Pointer Ectopic expression and enhanced activity of SIRT1 attenuate JNK phosphorylation. Black-Right-Pointing-Pointer Inhibition of SIRT1 activity restores resistance to oxidation-induced apoptosis through JNK activation. -- Abstract: We previously showed that SIRT1 deacetylase inhibits proliferation of hepatocellular carcinoma cells expressing hepatitis B virus (HBV) X protein (HBX), by destabilization of {beta}-catenin. Here, we report another role for SIRT1 in HBX-mediated resistance to oxidative stress. Ectopic expression and enhanced activity of SIRT1 sensitize Hep3B cells stably expressing HBX to oxidative stress-induced apoptosis. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for sensitization of oxidation-mediated apoptosis. Furthermore, ectopic expression of SIRT1 and treatment with resveratrol (a SIRT1 activator) attenuated JNK phosphorylation, which is a prerequisite for resistance to oxidative stress-induced apoptosis. Conversely, suppression of SIRT1 activity with nicotinamide inhibited the effect of resveratrol on JNK phosphorylation, leading to restoration of resistance to oxidation-induced apoptosis. Taken together, these results suggest that up-regulation of SIRT1 under oxidative stress may be a therapeutic strategy for treatment of hepatocellular carcinoma cells related to HBV through inhibition of JNK activation.

  1. Oxidative stress is involved in Patulin induced apoptosis in HEK293 cells.

    Science.gov (United States)

    Zhang, Baigang; Peng, Xiaoli; Li, Guanghui; Xu, Yunfeng; Xia, Xiaodong; Wang, Qian

    2015-02-01

    Patulin (PAT) is one of the most widely disseminated mycotoxins found in agricultural products and could cause renal damage. However, the mechanism of cell damage remains obscure. In this study, the human embryonic kidney cells (HEK293) were treated with PAT (2.5-15 μM). The cytotoxicity was assessed with MTT assay and apoptotic cells were detected by flow cytometry, and further identified by chromatin condensation and nuclear fragmentation with Hoechst 33342 under fluorescence microscope. Reactive oxygen species (ROS) with DCFH-DA was analyzed by fluorometry. The activities of superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT) and malondialdehyde (MDA) content were determined to reveal the potential mechanism of PAT induced apoptosis. The mitochondrial membrane potential was measured by JC-1 probe. The results showed that PAT dose-dependently inhibited the growth of HEK293 cells and resulted in apoptosis in HEK293 cells. Treatment with PAT could induce ROS and MDA accumulation, accompanied by the losses of SOD, CAT, GSH and disruption of the mitochondrial membrane potential. These data suggest that PAT may induce apoptosis in HEK293 cells, in which oxidative stress is involved.

  2. DNA damage in Nijmegen Breakage Syndrome cells leads to PARP hyperactivation and increased oxidative stress.

    Directory of Open Access Journals (Sweden)

    Harald Krenzlin

    Full Text Available Nijmegen Breakage Syndrome (NBS, an autosomal recessive genetic instability syndrome, is caused by hypomorphic mutation of the NBN gene, which codes for the protein nibrin. Nibrin is an integral member of the MRE11/RAD50/NBN (MRN complex essential for processing DNA double-strand breaks. Cardinal features of NBS are immunodeficiency and an extremely high incidence of hematological malignancies. Recent studies in conditional null mutant mice have indicated disturbances in redox homeostasis due to impaired DSB processing. Clearly this could contribute to DNA damage, chromosomal instability, and cancer occurrence. Here we show, in the complete absence of nibrin in null mutant mouse cells, high levels of reactive oxygen species several hours after exposure to a mutagen. We show further that NBS patient cells, which unlike mouse null mutant cells have a truncated nibrin protein, also have high levels of reactive oxygen after DNA damage and that this increased oxidative stress is caused by depletion of NAD+ due to hyperactivation of the strand-break sensor, Poly(ADP-ribose polymerase. Both hyperactivation of Poly(ADP-ribose polymerase and increased ROS levels were reversed by use of a specific Poly(ADP-ribose polymerase inhibitor. The extremely high incidence of malignancy among NBS patients is the result of the combination of a primary DSB repair deficiency with secondary oxidative DNA damage.

  3. Staphylococcal response to oxidative stress

    Directory of Open Access Journals (Sweden)

    Rosmarie eGaupp

    2012-03-01

    Full Text Available Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria’s interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host.

  4. The effect of oxidative stress on human red cells glutathione peroxidase, glutathione reductase level, and prevalence of anemia among diabetics

    Directory of Open Access Journals (Sweden)

    Hisham Waggiallah

    2011-01-01

    Full Text Available Background: The oxidative stress is considered as major consequence of diabetes mellitus affecting red cell antioxidant enzymes. Aim: The present study was conducted to assess the impact of oxidative stress (reduced glutathione on glutathione peroxidase, and glutathione reductse and prevalence of anemia among diabetic patients. Materials and Methods: The study involved 100 adult patients attending Buraidah Central Hospital and 30 healthy controls. Blood samples were collected and analyzed for glutathione (GSH concentration, glutathione peroxidase (GPO, glutathione reductase (GR, fasting blood sugar (RBS, hemoglobin (HGB, red cell count (RBCs hematocrit (HCT mean cell volume (MCV mean cell hemoglobin (MCH and mean cell hemoglobin concentration (MCHC and hemoglobin A1c. Blood urea, serum creatinine, and microalbuminuria were measured to exclude diabetes mellitus nephropathy. Results : were obtained showed significant correlation between deficiency of glutathione peroxidase, glutathione reductase and deficient of glutathione among diabetics, which has significant correlation between low hemoglobin concentration (females <120 g/L, males <130 g/L, also there is low concentration of red cell count and red cell indices (MCV, MCH and MCHC. The prevalence of anemia was 22% in diabetes patients. Conclusion: It can be concluded that there is strong significant effect of oxidative stress (reduced glutathione on glutathione peroxidase, glutathione reductase level these may reduce hemoglobin concentration in diabetic patients. This means oxidative stress of diabetes mellitus is the possible cause of anemia in diabetics without nephropathy.

  5. Methacryloxylethyl Cetyl Ammonium Chloride Induces DNA Damage and Apoptosis in Human Dental Pulp Cells via Generation of Oxidative Stress.

    Science.gov (United States)

    Jiao, Yang; Ma, Sai; Wang, Yirong; Li, Jing; Shan, Lequn; Sun, Jinlong; Chen, Jihua

    2016-01-01

    The polymerizable antibacterial monomer methacryloxylethyl cetyl ammonium chloride (DMAE-CB) has provided an effective strategy to combat dental caries. However, the application of such material raises the question about the biological safety and the question remains open. The mechanism of this toxic action, however, is not yet clearly understood. The present study aims at providing novel insight into the possible causal link between cellular oxidative stress and DNA damage, as well as apoptosis in human dental pulp cells exposed to DMAE-CB. The enhanced formation of reactive oxygen species and depletion of glutathione, as well as differential changes in activities of superoxide dismutase, glutathione peroxidase, and catalase in DMAE-CB-treated cells indicated oxidative stress. By using substances that can alter GSH synthesis, we found that GSH was the key component in the regulation of cell response towards oxidative stress induced by DMAE-CB. The increase in oxidative stress-sensitive 8-Oxo-2'-deoxyguanosine (8-OHdG) content, formation of γ-H2AX and cell cycle G1 phase arrest indicated that DNA damage occurred as a result of the interaction between DNA base and ROS beyond the capacities of antioxidant mechanisms in cells exposed to DMAE-CB. Such oxidative DNA damage thus triggers the activation of ataxia telangiectasia-mutated (ATM) signaling, the intrinsic apoptotic pathway, and destruction of mitochondrial morphology and function.

  6. Asymmetric dimethylarginine exacerbates Aβ-induced toxicity and oxidative stress in human cell and Caenorhabditis elegans models of Alzheimer disease.

    Science.gov (United States)

    Luo, Yunfeng; Yue, Wenhui; Quan, Xin; Wang, Yue; Zhao, Baolu; Lu, Zhongbing

    2015-02-01

    Growing evidence suggests a strong association between cardiovascular risk factors and incidence of Alzheimer disease (AD). Asymmetric dimethylarginine (ADMA), the endogenous nitric oxide synthase inhibitor, has been identified as an independent cardiovascular risk factor and is also increased in plasma of patients with AD. However, whether ADMA is involved in the pathogenesis of AD is unknown. In this study, we found that ADMA content was increased in a transgenic Caenorhabditis elegans β-amyloid (Aβ) overexpression model, strain CL2006, and in human SH-SY5Y cells overexpressing the Swedish mutant form of human Aβ precursor protein (APPsw). Moreover, ADMA treatment exacerbated Aβ-induced paralysis and oxidative stress in CL2006 worms and further elevated oxidative stress and Aβ secretion in APPsw cells. Knockdown of type 1 protein arginine N-methyltransferase to reduce ADMA production failed to show a protective effect against Aβ toxicity, but resulted in more paralysis in CL2006 worms as well as increased oxidative stress and Aβ secretion in APPsw cells. However, overexpression of dimethylarginine dimethylaminohydrolase 1 (DDAH1) to promote ADMA degradation significantly attenuated oxidative stress and Aβ secretion in APPsw cells. Collectively, our data support the hypothesis that elevated ADMA contributes to the pathogenesis of AD. Our findings suggest that strategies to increase DDAH1 activity in neuronal cells may be a novel approach to attenuating AD development.

  7. Fenofibrate suppressed proliferation and migration of human neuroblastoma cells via oxidative stress dependent of TXNIP upregulation

    Energy Technology Data Exchange (ETDEWEB)

    Su, Cunjin; Shi, Aiming; Cao, Guowen [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Tao, Tao [Department of Urology, Zhongda Hospital, Medical School of Southeast University, Nanjing, 210009 (China); Chen, Ruidong [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Zhanhong; Shen, Zhu; Tao, Hong; Cao, Bin [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Duanmin, E-mail: hudmsdfey@sina.com [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Bao, Junjie, E-mail: baojjsdfey@sina.com [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China)

    2015-05-15

    There are no appropriate drugs for metastatic neuroblastoma (NB), which is the most common extra-cranial solid tumor for childhood. Thioredoxin binding protein (TXNIP), the endogenous inhibitor of ROS elimination, has been identified as a tumor suppressor in various solid tumors. It reported that fenofibrate exerts anti-tumor effects in several human cancer cell lines. However, its detail mechanisms remain unclear. The present study assessed the effects of fenofibrate on NB cells and investigated TXNIP role in its anti-tumor mechanisms. We used MTT assay to detect cells proliferation, starch wound test to investigate cells migration, H{sub 2}DCF-DA to detect intracellular ROS, siRNA to interfere TXNIP and peroxisome proliferator-androgen receptor-alpha (PPAR-α) expression, western blot to determine protein levels, flow cytometry to analyze apoptosis. Fenofibrate suppressed proliferation and migration of NB cells, remarkably increased intracellular ROS, upregulated TXNIP expression, promoted cell apoptosis. Furthermore, inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. Our results indicated the anti-tumor role of fenofibrate on NB cells by exacerbating oxidative stress and inducing apoptosis was dependent on the upregulation of TXNIP. - Highlights: • We found that fenofibrate suppressed proliferation and migration of NB cells. • We found that fenofibrate remarkably increased intracellular ROS, upregulated TXNIP expression, and promoted cell apoptosis. • Inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. • Our results indicated the anti-tumor role of fenofibrate on NB cells was dependent on the upregulation of TXNIP.

  8. SIRT1 positively regulates autophagy and mitochondria function in embryonic stem cells under oxidative stress.

    Science.gov (United States)

    Ou, Xuan; Lee, Man Ryul; Huang, Xinxin; Messina-Graham, Steven; Broxmeyer, Hal E

    2014-05-01

    SIRT1, an NAD-dependent deacetylase, plays a role in regulation of autophagy. SIRT1 increases mitochondrial function and reduces oxidative stress, and has been linked to age-related reactive oxygen species (ROS) generation, which is highly dependent on mitochondrial metabolism. H2O2 induces oxidative stress and autophagic cell death through interference with Beclin 1 and the mTOR signaling pathways. We evaluated connections between SIRT1 activity and induction of autophagy in murine (m) and human (h) embryonic stem cells (ESCs) upon ROS challenge. Exogenous H2 O2 (1 mM) induced apoptosis and autophagy in wild-type (WT) and Sirt1-/- mESCs. High concentrations of H2O2 (1 mM) induced more apoptosis in Sirt1-/-, than in WT mESCs. However, addition of 3-methyladenine, a widely used autophagy inhibitor, in combination with H2O2 induced more cell death in WT than in Sirt1-/- mESCs. Decreased induction of autophagy in Sirt1-/- mESCs was demonstrated by decreased conversion of LC3-I to LC3-II, lowered expression of Beclin-1, and decreased LC3 punctae and LysoTracker staining. H2O2 induced autophagy with loss of mitochondrial membrane potential and disruption of mitochondrial dynamics in Sirt1-/- mESCs. Increased phosphorylation of P70/85-S6 kinase and ribosomal S6 was noted in Sirt1-/- mESCs, suggesting that SIRT1 regulates the mTOR pathway. Consistent with effects in mESCs, inhibition of SIRT1 using Lentivirus-mediated SIRT1 shRNA in hESCs demonstrated that knockdown of SIRT1 decreased H2O2-induced autophagy. This suggests a role for SIRT1 in regulating autophagy and mitochondria function in ESCs upon oxidative stress, effects mediated at least in part by the class III PI3K/Beclin 1 and mTOR pathways.

  9. Erythropoietin and oxidative stress.

    Science.gov (United States)

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2008-05-01

    Unmitigated oxidative stress can lead to diminished cellular longevity, accelerated aging, and accumulated toxic effects for an organism. Current investigations further suggest the significant disadvantages that can occur with cellular oxidative stress that can lead to clinical disability in a number of disorders, such as myocardial infarction, dementia, stroke, and diabetes. New therapeutic strategies are therefore sought that can be directed toward ameliorating the toxic effects of oxidative stress. Here we discuss the exciting potential of the growth factor and cytokine erythropoietin for the treatment of diseases such as cardiac ischemia, vascular injury, neurodegeneration, and diabetes through the modulation of cellular oxidative stress. Erythropoietin controls a variety of signal transduction pathways during oxidative stress that can involve Janus-tyrosine kinase 2, protein kinase B, signal transducer and activator of transcription pathways, Wnt proteins, mammalian forkhead transcription factors, caspases, and nuclear factor kappaB. Yet, the biological effects of erythropoietin may not always be beneficial and may be poor tolerated in a number of clinical scenarios, necessitating further basic and clinical investigations that emphasize the elucidation of the signal transduction pathways controlled by erythropoietin to direct both successful and safe clinical care.

  10. Imipramine protects retinal ganglion cells from oxidative stress through the tyrosine kinase receptor B signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Ming-lei Han; Guo-hua Liu; Jin Guo; Shu-juan Yu; Jing Huang

    2016-01-01

    Retinal ganglion cell (RGC) degeneration is irreversible in glaucoma and tyrosine kinase receptor B (TrkB)-associated signaling pathways have been implicated in the process. In this study, we attempted to examine whether imipramine, a tricyclic antidepressant, may protect hydrogen peroxide (H2O2)-induced RGC degeneration through the activation of the TrkB pathway in RGC-5 cell lines. RGC-5 cell lines were pre-treated with imipramine 30 minutes before exposure to H2O2. Western blot assay showed that in H2O2-damaged RGC-5 cells, imipramine activated TrkB pathways through extracellular signal-regulated protein kinase/TrkB phosphorylation. TUNEL staining assay also demonstrated that imipramine ameliorated H2O2-induced apoptosis in RGC-5 cells. Finally, TrkB-IgG intervention was able to reverse the protective effect of imipramine on H2O2-induced RGC-5 apoptosis. Imipramine therefore protects RGCs from oxidative stress-induced apoptosis through the TrkB signaling pathway.

  11. Imipramine protects retinal ganglion cells from oxidative stress through the tyrosine kinase receptor B signaling pathway

    Directory of Open Access Journals (Sweden)

    Ming-lei Han

    2016-01-01

    Full Text Available Retinal ganglion cell (RGC degeneration is irreversible in glaucoma and tyrosine kinase receptor B (TrkB-associated signaling pathways have been implicated in the process. In this study, we attempted to examine whether imipramine, a tricyclic antidepressant, may protect hydrogen peroxide (H 2 O 2 -induced RGC degeneration through the activation of the TrkB pathway in RGC-5 cell lines. RGC-5 cell lines were pre-treated with imipramine 30 minutes before exposure to H 2 O 2 . Western blot assay showed that in H 2 O 2 -damaged RGC-5 cells, imipramine activated TrkB pathways through extracellular signal-regulated protein kinase/TrkB phosphorylation. TUNEL staining assay also demonstrated that imipramine ameliorated H 2 O 2 -induced apoptosis in RGC-5 cells. Finally, TrkB-IgG intervention was able to reverse the protective effect of imipramine on H 2 O 2 -induced RGC-5 apoptosis. Imipramine therefore protects RGCs from oxidative stress-induced apoptosis through the TrkB signaling pathway.

  12. Effects of Cigarette Smoke Condensate on Oxidative Stress, Apoptotic Cell Death, and HIV Replication in Human Monocytic Cells.

    Directory of Open Access Journals (Sweden)

    Pss Rao

    Full Text Available While cigarette smoking is prevalent amongst HIV-infected patients, the effects of cigarette smoke constituents in cells of myeloid lineage are poorly known. Recently, we have shown that nicotine induces oxidative stress through cytochrome P450 (CYP 2A6-mediated pathway in U937 monocytic cells. The present study was designed to examine the effect of cigarette smoke condensate (CSC, which contains majority of tobacco constituents, on oxidative stress, cytotoxicity, expression of CYP1A1, and/or HIV-1 replication in HIV-infected (U1 and uninfected U937 cells. The effects of CSC on induction of CYP1 enzymes in HIV-infected primary macrophages were also analyzed. The results showed that the CSC-mediated increase in production of reactive oxygen species (ROS in U937 cells is dose- and time-dependent. Moreover, CSC treatment was found to induce cytotoxicity in U937 cells through the apoptotic pathway via activation of caspase-3. Importantly, pretreatment with vitamin C blocked the CSC-mediated production of ROS and induction of caspase-3 activity. In U1 cells, acute treatment of CSC increased ROS production at 6H (>2-fold and both ROS (>2 fold and HIV-1 replication (>3-fold after chronic treatment. The CSC mediated effects were associated with robust induction in the expression of CYP1A1 mRNA upon acute CSC treatment of U937 and U1 cells (>20-fold, and upon chronic CSC treatment to U1 cells (>30-fold. In addition, the CYP1A1 induction in U937 cells was mediated through the aromatic hydrocarbon receptor pathway. Lastly, CSC, which is known to increase viral replication in primary macrophages, was also found to induce CYP1 enzymes in HIV-infected primary macrophages. While mRNA levels of both CYP1A1 and CYP1B1 were elevated following CSC treatment, only CYP1B1 protein levels were increased in HIV-infected primary macrophages. In conclusion, these results suggest a possible association between oxidative stress, CYP1 expression, and viral replication in

  13. Oxidative stress induces transient O-GlcNAc elevation and tau dephosphorylation in SH-SY5Y cells.

    Science.gov (United States)

    Kátai, Emese; Pál, József; Poór, Viktor Soma; Purewal, Rupeena; Miseta, Attila; Nagy, Tamás

    2016-12-01

    O-linked β-N-acetlyglucosamine or O-GlcNAc modification is a dynamic post-translational modification occurring on the Ser/Thr residues of many intracellular proteins. The chronic imbalance between phosphorylation and O-GlcNAc on tau protein is considered as one of the main hallmarks of Alzheimer's disease. In recent years, many studies also showed that O-GlcNAc levels can elevate upon acute stress and suggested that this might facilitate cell survival. However, many consider chronic stress, including oxidative damage as a major risk factor in the development of the disease. In this study, using the neuronal cell line SH-SY5Y we investigated the dynamic nature of O-GlcNAc after treatment with 0.5 mM H2 O2 for 30 min. to induce oxidative stress. We found that overall O-GlcNAc quickly increased and reached peak level at around 2 hrs post-stress, then returned to baseline levels after about 24 hrs. Interestingly, we also found that tau protein phosphorylation at site S262 showed parallel, whereas at S199 and PHF1 sites showed inverse dynamic to O-Glycosylation. In conclusion, our results show that temporary elevation in O-GlcNAc modification after H2 O2 -induced oxidative stress is detectable in cells of neuronal origin. Furthermore, oxidative stress changes the dynamic balance between O-GlcNAc and phosphorylation on tau proteins.

  14. JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival under oxidative stress.

    Science.gov (United States)

    Jia, Xin; Zhao, Chen; Chen, Qishan; Du, Yuxiang; Huang, Lijuan; Ye, Zhimin; Ren, Xiangrong; Wang, Shasha; Lee, Chunsik; Tang, Zhongshu; Li, Xuri; Ju, Rong

    2017-04-03

    Junctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.

  15. Neonates with sickle cell disease are vulnerable to blue light phototherapy-induced oxidative stress and proinflammatory cytokine elevations.

    Science.gov (United States)

    Chaudhari, Hemakshi; Goyal, Sameer; Patil, Chandragouda

    2016-11-01

    Sickle cell disease is a frequent genetic anomaly characterized by altered molecular structure of hemoglobin resulting into crescent-like deformation of the red blood corpuscles. Neonatal jaundice is a frequent co-morbidity in sickle cell disease. Phototherapy induces isomerization of bilirubin rendering it extractable through urine and hence it is used as a routine treatment of neonatal jaundice. An exposure to light phototherapy as a treatment of neonatal jaundice induces oxidative stress. It is hypothesized that such exposure of neonates with sickle cell disease to the blue light phototherapy as a treatment of neonatal jaundice induces severe oxidative stress and increases the levels of proinflammatory cytokines. This hypothesis is supported with two case studies of sickle cell disease suffering neonates who were exposed to blue light phototherapy to treat jaundice. In both these cases, exposure to phototherapy induced oxidative stress (increased lipid peroxidation and superoxide dismutase, slight change in activity of catalase and GSH) and elevated the levels of proinflammatory cytokine (TNFα, IL-1, and IL-6) in the sickle cell disease suffering neonates. These observations warrant further investigations to determine the consequences and clinical significance of the blue phototherapy-induced oxidative and proinflammatory stress in Sickle cell disease suffering neonates exposed to phototherapy as a treatment of jaundice.

  16. Tart cherry extracts reduce inflammatory and oxidative stress signaling in microglial cells

    Science.gov (United States)

    Tart cherries contain an array of polyphenols that can decrease inflammation and oxidative stress (OS), which contribute to cognitive declines seen in aging populations. Previous studies have shown that polyphenols from dark-colored fruits can reduce stress-mediated signaling in BV-2 mouse microglia...

  17. Tumor-associated macrophages favor C26 murine colon carcinoma cell proliferation in an oxidative stress-dependent manner.

    Science.gov (United States)

    Luput, Lavinia; Licarete, Emilia; Sesarman, Alina; Laura, Patras; Alupei, Marius Costel; Banciu, Manuela

    2017-02-17

    The role of tumor-associated macrophages (TAMs) in the development of colon carcinoma is still controversial. Therefore, the present study aimed to investigate the TAM‑driven processes that may affect colon cancer cell proliferation. To achieve this purpose, murine macrophages were co-cultured with C26 murine colon carcinoma cells at a cell density ratio that approximates physiological conditions for colon carcinoma development in vivo. In this respect, the effects of TAM-mediated angiogenesis, inflammation and oxidative stress on the proliferative capacity of C26 murine colon carcinoma cells were studied. To gain insight into the TAM-driven oxidative stress, NADPH oxidase, the main pro-oxidant enzyme in macrophages, was inhibited. Our data revealed that the stimulatory effects of TAMs on C26 cell proliferation may be related mainly to their pro-oxidant actions exerted by NADPH oxidase activity, which maintains the redox status and the angiogenic capacity of the tumor microenvironment. Additionally, the anti-inflammatory and pro-angiogenic effects of TAMs on tumor cells were found to create a favorable microenvironment for C26 colon carcinoma development and progression. In conclusion, our data confirmed the protumor role of TAMs in the development of colon carcinoma in an oxidative stress-dependent manner that potentiates the angiogenic capacity of the tumor microenvironment. These data may offer valuable information for future tumor-targeted therapies based on TAM 're-education' strategies.

  18. Selenium reduces mobile phone (900 MHz)-induced oxidative stress, mitochondrial function, and apoptosis in breast cancer cells.

    Science.gov (United States)

    Kahya, Mehmet Cemal; Nazıroğlu, Mustafa; Çiğ, Bilal

    2014-08-01

    Exposure to mobile phone-induced electromagnetic radiation (EMR) may affect biological systems by increasing free oxygen radicals, apoptosis, and mitochondrial depolarization levels although selenium may modulate the values in cancer. The present study was designed to investigate the effects of 900 MHz radiation on the antioxidant redox system, apoptosis, and mitochondrial depolarization levels in MDA-MB-231 breast cancer cell line. Cultures of the cancer cells were divided into four main groups as controls, selenium, EMR, and EMR + selenium. In EMR groups, the cells were exposed to 900 MHz EMR for 1 h (SAR value of the EMR was 0.36 ± 0.02 W/kg). In selenium groups, the cells were also incubated with sodium selenite for 1 h before EMR exposure. Then, the following values were analyzed: (a) cell viability, (b) intracellular ROS production, (c) mitochondrial membrane depolarization, (d) cell apoptosis, and (e) caspase-3 and caspase-9 values. Selenium suppressed EMR-induced oxidative cell damage and cell viability (MTT) through a reduction of oxidative stress and restoring mitochondrial membrane potential. Additionally, selenium indicated anti-apoptotic effects, as demonstrated by plate reader analyses of apoptosis levels and caspase-3 and caspase-9 values. In conclusion, 900 MHz EMR appears to induce apoptosis effects through oxidative stress and mitochondrial depolarization although incubation of selenium seems to counteract the effects on apoptosis and oxidative stress.

  19. Upon oxidative stress, the antiapoptotic Hsp60/procaspase-3 complex persists in mucoepidermoid carcinoma cells

    Directory of Open Access Journals (Sweden)

    C Campanella

    2009-08-01

    Full Text Available Hsp60, a mitochondrial chaperonin highly conserved during evolution, has been found elevated in the cytosol of cancer cells, both in vivo and in vitro, but its role in determining apoptosis during oxidative stress (OS has not yet been fully elucidated. The aim of the present work was to study the effects of OS on Hsp60 levels and its interactions with procaspase- 3 (p-C3 and p53 in tumor cells. NCI-H292 (mucoepidermoid carcinoma cells were exposed to various concentrations of hydrogen peroxide (H2O2 for 24 hours. Cell viability was determined by Trypan blue and MTT assays. DNA damage was assessed by the Comet assay, and apoptosis was measured by the AnnexinV cytofluorimetric test. Exposure to increasing concentrations of H2O2 resulted in a reduction of cell viability, DNA damage, and early apoptotic phenomena. Hsp60, p-C3, p53, and p21 were assessed by Western blotting and immunocytochemistry before and after OS. Hsp60 and p-C3 were present before and after OS induction. Immunoprecipitation experiments showed an Hsp60/p-C3 complex before OS that persisted after it, while an Hsp60/p53 complex was not detected in either condition. The presence of wild type (wt p53 was confirmed by RT-PCR, and p21 detection suggested p53 activation after OS. We postulate that, although OS may induce early apoptosis in NCI-H292 cells, Hsp60 exerts an anti-apoptotic effect in these cells and, by extension, it may do so in other cancer cells.

  20. Substance P promotes the recovery of oxidative stress-damaged retinal pigmented epithelial cells by modulating Akt/GSK-3β signaling

    Science.gov (United States)

    Baek, Sang-Min; Yu, Seung-Young; Son, Youngsook

    2016-01-01

    Purpose Senescence of the retina causes an accumulation of reactive oxygen species (ROS). Oxidative stress associated with ROS can damage RPE cells, leading to neovascularization and severe ocular disorders, including age-related macular degeneration (AMD). Thus, the early treatment of the damage caused by oxidative stress is critical for preventing the development of ocular diseases such as AMD. In this study, we examined the role of substance P (SP) in the recovery of RPE cells damaged by oxidative stress. Methods To induce oxidative stress, RPE cells were treated with H2O2 at various doses. Recovery from oxidative stress was studied following treatment with SP by analyzing cell viability, cell proliferation, cell apoptosis, and Akt/glycogen synthase kinase (GSK)-3β activation in RPE cells in vitro. Results H2O2 treatment reduced cellular viability in a dose-dependent manner. SP inhibited the reduction of cell viability due to H2O2 and caused increased cell proliferation and decreased cell apoptosis. Cell survival under oxidative stress requires the activation of Akt signaling that enables cells to resist oxidative stress-induced damage. SP treatment activated Akt/GSK-3β signaling in RPE cells, which were damaged due to oxidative stress, and the inhibition of Akt signaling in SP-treated RPE cells prevented SP-induced recovery. Pretreatment with the neurokinin 1 receptor (NK1R) antagonist reduced the recovery effect of SP on damaged RPE cells. Conclusions SP can protect RPE cells from oxidant-induced cell death by activating Akt/GSK-3β signaling via NK1R. This study suggests the possibility of SP as a treatment for oxidative stress-related diseases. PMID:27582624

  1. Physico-chemical properties based differential toxicity of graphene oxide/reduced graphene oxide in human lung cells mediated through oxidative stress

    Science.gov (United States)

    Mittal, Sandeep; Kumar, Veeresh; Dhiman, Nitesh; Chauhan, Lalit Kumar Singh; Pasricha, Renu; Pandey, Alok Kumar

    2016-12-01

    Goraphene derivatives (GD) are currently being evaluated for technological and biomedical applications owing to their unique physico-chemical properties over other carbon allotrope such as carbon nanotubes (CNTs). But, the possible association of their properties with underlying in vitro effects have not fully examined. Here, we assessed the comparative interaction of three GD - graphene oxide (GO), thermally reduced GO (TRGO) and chemically reduced GO (CRGO), which significantly differ in their lateral size and functional groups density, with phenotypically different human lung cells; bronchial epithelial cells (BEAS-2B) and alveolar epithelial cells (A549). The cellular studies demonstrate that GD significantly ineternalize and induce oxidative stress mediated cytotoxicity in both cells. The toxicity intensity was in line with the reduced lateral size and increased functional groups revealed more toxicity potential of TRGO and GO respectively. Further, A549 cells showed more susceptibility than BEAS-2B which reflected cell type dependent differential cellular response. Molecular studies revealed that GD induced differential cell death mechanism which was efficiently prevented by their respective inhibitors. This is prior study to the best of our knowledge involving TRGO for its safety evaluation which provided invaluable information and new opportunities for GD based biomedical applications.

  2. Diallyl Trisulfide Suppresses Oxidative Stress-Induced Activation of Hepatic Stellate Cells through Production of Hydrogen Sulfide.

    Science.gov (United States)

    Zhang, Feng; Jin, Huanhuan; Wu, Li; Shao, Jiangjuan; Zhu, Xiaojing; Chen, Anping; Zheng, Shizhong

    2017-01-01

    Accumulating data reveal that garlic has beneficial effects against chronic liver disease. We previously reported that diallyl trisulfide (DATS), the primary organosulfur compound in garlic, reduced fibrosis and attenuated oxidative stress in rat fibrotic liver. The present study was aimed at elucidating the underlying mechanisms. The primary rat hepatic stellate cells (HSCs) were cultured and stimulated with hydrogen peroxide (H2O2) for inducing HSC activation under oxidative stress. We examined the effects of DATS on the profibrogenic properties and oxidative stress in H2O2-treated HSCs. The results showed that DATS suppressed and reduced fibrotic marker expression in HSCs. DATS arrested cell cycle at G2/M checkpoint associated with downregulating cyclin B1 and cyclin-dependent kinase 1, induced caspase-dependent apoptosis, and reduced migration in HSCs. Moreover, intracellular levels of reactive oxygen species and lipid peroxide were decreased by DATS, but intracellular levels of glutathione were increased in HSCs. Furthermore, DATS significantly elevated hydrogen sulfide (H2S) levels within HSCs, but iodoacetamide (IAM) reduced H2S levels and significantly abrogated DATS production of H2S within HSCs. IAM also abolished all the inhibitory effects of DATS on the profibrogenic properties and oxidative stress in HSCs. Altogether, we demonstrated an H2S-associated mechanism underlying DATS inhibition of profibrogenic properties and alleviation of oxidative stress in HSCs. Modulation of H2S production may represent a therapeutic remedy for liver fibrosis.

  3. Oxidative stress-dependent changes in immune responses and cell death in the substantia nigra after ozone exposure in rat

    Science.gov (United States)

    Rivas-Arancibia, Selva; Zimbrón, Luis Fernando Hernández; Rodríguez-Martínez, Erika; Maldonado, Perla D.; Borgonio Pérez, Gabino; Sepúlveda-Parada, María

    2015-01-01

    Parkinson's disease has been associated with the selective loss of neurons in the substantia nigra pars compacta. Increasing evidence suggests that oxidative stress plays a major role. The resulting increase in reactive oxygen species triggers a sequence of events that leads to cell damage, activation of microglia cells and neuroinflammatory responses. Our objective was to study whether chronic exposure to low doses of ozone, which produces oxidative stress itself, induces progressive cell death in conjunction with glial alterations in the substantia nigra. Animals were exposed to an ozone-free air stream (control) or to low doses of ozone for 7, 15, 30, 60, or 90 days. Each group underwent (1) spectrophotometric analysis for protein oxidation; (2) western blot testing for microglia reactivity and nuclear factor kappa B expression levels; and (3) immunohistochemistry for cytochrome c, GFAP, Iba-1, NFkB, and COX-2. Our results indicate that ozone induces an increase in protein oxidation levels, changes in activated astrocytes and microglia, and cell death. NFkB and cytochrome c showed an increase until 30 days of exposure, while cyclooxygenase 2 in the substantia nigra increased from 7 days up to 90 days of repetitive ozone exposure. These results suggest that oxidative stress caused by ozone exposure induces changes in inflammatory responses and progressive cell death in the substantia nigra in rats, which could also be occurring in Parkinson's disease. PMID:25999851

  4. Salicylic acid antagonism of EDS1-driven cell death is important for immune and oxidative stress responses in Arabidopsis.

    Science.gov (United States)

    Straus, Marco R; Rietz, Steffen; Ver Loren van Themaat, Emiel; Bartsch, Michael; Parker, Jane E

    2010-05-01

    Reactive oxygen species (ROS) have emerged as signals in the responses of plants to stress. Arabidopsis Enhanced Disease Susceptibility1 (EDS1) regulates defense and cell death against biotrophic pathogens and controls cell death propagation in response to chloroplast-derived ROS. Arabidopsis Nudix hydrolase7 (nudt7) mutants are sensitized to photo-oxidative stress and display EDS1-dependent enhanced resistance, salicylic acid (SA) accumulation and initiation of cell death. Here we explored the relationship between EDS1, EDS1-regulated SA and ROS by examining gene expression profiles, photo-oxidative stress and resistance phenotypes of nudt7 mutants in combination with eds1 and the SA-biosynthetic mutant, sid2. We establish that EDS1 controls steps downstream of chloroplast-derived O(2)(*-) that lead to SA-assisted H(2)O(2) accumulation as part of a mechanism limiting cell death. A combination of EDS1-regulated SA-antagonized and SA-promoted processes is necessary for resistance to host-adapted pathogens and for a balanced response to photo-oxidative stress. In contrast to SA, the apoplastic ROS-producing enzyme NADPH oxidase RbohD promotes initiation of cell death during photo-oxidative stress. Thus, chloroplastic O(2)(*-) signals are processed by EDS1 to produce counter-balancing activities of SA and RbohD in the control of cell death. Our data strengthen the idea that EDS1 responds to the status of O(2)(*-) or O(2)(*-)-generated molecules to coordinate cell death and defense outputs. This activity may enable the plant to respond flexibly to different biotic and abiotic stresses in the environment.

  5. Influence of glutathione-S-transferase (GST) inhibition on lung epithelial cell injury: role of oxidative stress and metabolism.

    Science.gov (United States)

    Fletcher, Marianne E; Boshier, Piers R; Wakabayashi, Kenji; Keun, Hector C; Smolenski, Ryszard T; Kirkham, Paul A; Adcock, Ian M; Barton, Paul J; Takata, Masao; Marczin, Nandor

    2015-06-15

    Oxidant-mediated tissue injury is key to the pathogenesis of acute lung injury. Glutathione-S-transferases (GSTs) are important detoxifying enzymes that catalyze the conjugation of glutathione with toxic oxidant compounds and are associated with acute and chronic inflammatory lung diseases. We hypothesized that attenuation of cellular GST enzymes would augment intracellular oxidative and metabolic stress and induce lung cell injury. Treatment of murine lung epithelial cells with GST inhibitors, ethacrynic acid (EA), and caffeic acid compromised lung epithelial cell viability in a concentration-dependent manner. These inhibitors also potentiated cell injury induced by hydrogen peroxide (H2O2), tert-butyl-hydroperoxide, and hypoxia and reoxygenation (HR). SiRNA-mediated attenuation of GST-π but not GST-μ expression reduced cell viability and significantly enhanced stress (H2O2/HR)-induced injury. GST inhibitors also induced intracellular oxidative stress (measured by dihydrorhodamine 123 and dichlorofluorescein fluorescence), caused alterations in overall intracellular redox status (as evidenced by NAD(+)/NADH ratios), and increased protein carbonyl formation. Furthermore, the antioxidant N-acetylcysteine completely prevented EA-induced oxidative stress and cytotoxicity. Whereas EA had no effect on mitochondrial energetics, it significantly altered cellular metabolic profile. To explore the physiological impact of these cellular events, we used an ex vivo mouse-isolated perfused lung model. Supplementation of perfusate with EA markedly affected lung mechanics and significantly increased lung permeability. The results of our combined genetic, pharmacological, and metabolic studies on multiple platforms suggest the importance of GST enzymes, specifically GST-π, in the cellular and whole lung response to acute oxidative and metabolic stress. These may have important clinical implications.

  6. Pathophysiology of cell phone radiation: oxidative stress and carcinogenesis with focus on male reproductive system

    Directory of Open Access Journals (Sweden)

    Kesari Kavindra K

    2009-10-01

    Full Text Available Abstract Hazardous health effects stemming from exposure to radiofrequency electromagnetic waves (RF-EMW emitted from cell phones have been reported in the literature. However, the cellular target of RF-EMW is still controversial. This review identifies the plasma membrane as a target of RF-EMW. In addition, the effects of RF-EMW on plasma membrane structures (i.e. NADH oxidase, phosphatidylserine, ornithine decarboxylase and voltage-gated calcium channels are discussed. We explore the disturbance in reactive oxygen species (ROS metabolism caused by RF-EMW and delineate NADH oxidase mediated ROS formation as playing a central role in oxidative stress (OS due to cell phone radiation (with a focus on the male reproductive system. This review also addresses: 1 the controversial effects of RF-EMW on mammalian cells and sperm DNA as well as its effect on apoptosis, 2 epidemiological, in vivo animal and in vitro studies on the effect of RF-EMW on male reproductive system, and 3 finally, exposure assessment and dosimetry by computational biomodeling.

  7. Pathophysiology of cell phone radiation: oxidative stress and carcinogenesis with focus on male reproductive system.

    Science.gov (United States)

    Desai, Nisarg R; Kesari, Kavindra K; Agarwal, Ashok

    2009-10-22

    Hazardous health effects stemming from exposure to radiofrequency electromagnetic waves (RF-EMW) emitted from cell phones have been reported in the literature. However, the cellular target of RF-EMW is still controversial. This review identifies the plasma membrane as a target of RF-EMW. In addition, the effects of RF-EMW on plasma membrane structures (i.e. NADH oxidase, phosphatidylserine, ornithine decarboxylase) and voltage-gated calcium channels are discussed. We explore the disturbance in reactive oxygen species (ROS) metabolism caused by RF-EMW and delineate NADH oxidase mediated ROS formation as playing a central role in oxidative stress (OS) due to cell phone radiation (with a focus on the male reproductive system). This review also addresses: 1) the controversial effects of RF-EMW on mammalian cells and sperm DNA as well as its effect on apoptosis, 2) epidemiological, in vivo animal and in vitro studies on the effect of RF-EMW on male reproductive system, and 3) finally, exposure assessment and dosimetry by computational biomodeling.

  8. Bisphenol S Interacts with Catalase and Induces Oxidative Stress in Mouse Liver and Renal Cells.

    Science.gov (United States)

    Zhang, Rui; Liu, Rutao; Zong, Wansong

    2016-08-31

    Bisphenol S (BPS) is present in multitudinous consumer products and detected in both food and water. It also has been a main substitute for bisphenol A (BPA) in the food-packaging industry. Yet, the toxicity of BPS is not fully understood. The present study of the toxicity of BPS was divided into two parts. First, oxidative stress, cell viability, apoptosis level, and catalase (CAT) activity in mouse hepatocytes and renal cells were investigated after BPS exposure. After 12 h of incubation with BPS, all of these parameters of hepatocytes and renal cells changed by >15% as the concentration of BPS ranged from 0.1 to 1 mM. Second, the direct interaction between BPS and CAT on the molecule level was investigated by multiple spectral methods and molecular docking investigations. BPS changed the structure and the activity of CAT through binding to the Gly 117 residue on the substrate channel of the enzyme. The main binding forces were hydrogen bond and hydrophobic force.

  9. Management of oxidative stress by microalgae.

    Science.gov (United States)

    Cirulis, Judith T; Scott, J Ashley; Ross, Gregory M

    2013-01-01

    The aim of this review is to provide an overview of the current research on oxidative stress in eukaryotic microalgae and the antioxidant compounds microalgae utilize to control oxidative stress. With the potential to exploit microalgae for the large-scale production of antioxidants, interest in how microalgae manage oxidative stress is growing. Microalgae can experience increased levels of oxidative stress and toxicity as a result of environmental conditions, metals, and chemicals. The defence mechanisms for microalgae include antioxidant enzymes such as superoxide dismutase, catalase, peroxidases, and glutathione reductase, as well as non-enzymatic antioxidant molecules such as phytochelatins, pigments, polysaccharides, and polyphenols. Discussed herein are the 3 areas the literature has focused on, including how conditions stress microalgae and how microalgae respond to oxidative stress by managing reactive oxygen species. The third area is how beneficial microalgae antioxidants are when administered to cancerous mammalian cells or to rodents experiencing oxidative stress.

  10. Heme Oxygenase-1 Protects Retinal Endothelial Cells against High Glucose- and Oxidative/Nitrosative Stress-Induced Toxicity

    Science.gov (United States)

    Castilho, Áurea F.; Aveleira, Célia A.; Leal, Ermelindo C.; Simões, Núria F.; Fernandes, Carolina R.; Meirinhos, Rita I.; Baptista, Filipa I.; Ambrósio, António F.

    2012-01-01

    Diabetic retinopathy is a leading cause of visual loss and blindness, characterized by microvascular dysfunction. Hyperglycemia is considered the major pathogenic factor for the development of diabetic retinopathy and is associated with increased oxidative/nitrosative stress in the retina. Since heme oxygenase-1 (HO-1) is an enzyme with antioxidant and protective properties, we investigated the potential protective role of HO-1 in retinal endothelial cells exposed to high glucose and oxidative/nitrosative stress conditions. Retinal endothelial cells were exposed to elevated glucose, nitric oxide (NO) and hydrogen peroxide (H2O2). Cell viability and apoptosis were assessed by MTT assay, Hoechst staining, TUNEL assay and Annexin V labeling. The production of reactive oxygen species (ROS) was detected by the oxidation of 2′,7′-dichlorodihydrofluorescein diacetate. The content of HO-1 was assessed by immunobloting and immunofluorescence. HO activity was determined by bilirubin production. Long-term exposure (7 days) of retinal endothelial cells to elevated glucose decreased cell viability and had no effect on HO-1 content. However, a short-time exposure (24 h) to elevated glucose did not alter cell viability, but increased both the levels of intracellular ROS and HO-1 content. Moreover, the inhibition of HO with SnPPIX unmasked the toxic effect of high glucose and revealed the protection conferred by HO-1. Oxidative/nitrosative stress conditions increased cell death and HO-1 protein levels. These effects of elevated glucose and HO inhibition on cell death were confirmed in primary endothelial cells (HUVECs). When cells were exposed to oxidative/nitrosative stress conditions there was also an increase in retinal endothelial cell death and HO-1 content. The inhibition of HO enhanced ROS production and the toxic effect induced by exposure to H2O2 and NOC-18 (NO donor). Overexpression of HO-1 prevented the toxic effect induced by H2O2 and NOC-18. In conclusion, HO-1

  11. Differential effects of nebivolol and metoprolol on arterial stiffness, circulating progenitor cells, and oxidative stress.

    Science.gov (United States)

    Hayek, Salim S; Poole, Joseph C; Neuman, Robert; Morris, Alanna A; Khayata, Mohamed; Kavtaradze, Nino; Topel, Matthew L; Binongo, Jose G; Li, Qunna; Jones, Dean P; Waller, Edmund K; Quyyumi, Arshed A

    2015-03-01

    Unlike traditional beta receptor antagonists, nebivolol activates nitric oxide. We hypothesized that therapy with nebivolol compared with metoprolol would improve arterial stiffness, increase levels of circulating progenitor cells (PC), and decrease oxidative stress (OS). In a randomized, double-blind, cross-over study, 30 hypertensive subjects received either once daily nebivolol or metoprolol succinate for 3 months each. Pulse wave velocity and augmentation index were measured using tonometry. Flow cytometry was used to measure circulating PC. OS was measured as plasma aminothiols. Measurements were performed at baseline, and repeated at 3 and 6 months. No significant differences were present between the levels of OS, arterial stiffness, and PC numbers during treatment with metoprolol compared with nebivolol. In subgroup analyses of beta-blocker naïve subjects (n = 19), nebivolol reduced pulse wave velocity significantly compared with metoprolol (-1.4 ± 1.9 vs. -0.1 ± 2.2; P = .005). Both nebivolol and metoprolol increased circulating levels of CD34+/CD133 + PC similarly (P = .05), suggesting improved regenerative capacity.

  12. Betaine treatment decreased oxidative stress, inflammation, and stellate cell activation in rats with alcoholic liver fibrosis.

    Science.gov (United States)

    Bingül, İlknur; Başaran-Küçükgergin, Canan; Aydın, A Fatih; Çoban, Jale; Doğan-Ekici, Işın; Doğru-Abbasoğlu, Semra; Uysal, Müjdat

    2016-07-01

    The aim of this study was to investigate the effect of betaine (BET) on alcoholic liver fibrosis in rats. Fibrosis was experimentally generated with ethanol plus carbon tetrachloride (ETH+CCl4) treatment. Rats were treated with ETH (5% v/v in drinking water) for 14 weeks. CCl4 was administered intraperitoneally (i.p.) 0.2mL/kg twice a week to rats in the last 6 weeks with/without commercial food containing BET (2% w/w). Serum hepatic damage markers, tumor necrosis factor-α, hepatic triglyceride (TG) and hydroxyproline (HYP) levels, and oxidative stress parameters were measured together with histopathologic observations. In addition, α-smooth muscle-actin (α-SMA), transforming growth factor-β1 (TGF-β1) and type I collagen (COL1A1) protein expressions were assayed immunohistochemically to evaluate stellate cell (HSC) activation. mRNA expressions of matrix metalloproteinase-2 (MMP-2) and its inhibitors (TIMP-1 and TIMP-2) were also determined. BET treatment diminished TG and HYP levels; prooxidant status and fibrotic changes; α-SMA, COL1A1 and TGF-β protein expressions; MMP-2, TIMP-1 and TIMP-2 mRNA expressions in the liver of fibrotic rats. In conclusion, these results indicate that the antifibrotic effect of BET may be related to its suppressive effects on oxidant and inflammatory processes together with HSC activation in alcoholic liver fibrosis.

  13. Autophagy of metallothioneins prevents TNF-induced oxidative stress and toxicity in hepatoma cells.

    Science.gov (United States)

    Ullio, Chiara; Brunk, Ulf T; Urani, Chiara; Melchioretto, Pasquale; Bonelli, Gabriella; Baccino, Francesco M; Autelli, Riccardo

    2015-01-01

    Lysosomal membrane permeabilization (LMP) induced by oxidative stress has recently emerged as a prominent mechanism behind TNF cytotoxicity. This pathway relies on diffusion of hydrogen peroxide into lysosomes containing redox-active iron, accumulated by breakdown of iron-containing proteins and subcellular organelles. Upon oxidative lysosomal damage, LMP allows relocation to the cytoplasm of low mass iron and acidic hydrolases that contribute to DNA and mitochondrial damage, resulting in death by apoptosis or necrosis. Here we investigate the role of lysosomes and free iron in death of HTC cells, a rat hepatoma line, exposed to TNF following metallothionein (MT) upregulation. Iron-binding MT does not normally occur in HTC cells in significant amounts. Intracellular iron chelation attenuates TNF and cycloheximide (CHX)-induced LMP and cell death, demonstrating the critical role of this transition metal in mediating cytokine lethality. MT upregulation, combined with starvation-activated MT autophagy almost completely suppresses TNF and CHX toxicity, while impairment of both autophagy and MT upregulation by silencing of Atg7, and Mt1a and/or Mt2a, respectively, abrogates protection. Interestingly, MT upregulation by itself has little effect, while stimulated autophagy alone depresses cytokine toxicity to some degree. These results provide evidence that intralysosomal iron-catalyzed redox reactions play a key role in TNF and CHX-induced LMP and toxicity. The finding that chelation of intralysosomal iron achieved by autophagic delivery of MT, and to some degree probably of other iron-binding proteins as well, into the lysosomal compartment is highly protective provides a putative mechanism to explain autophagy-related suppression of death by TNF and CHX.

  14. Crocetin protects ultraviolet A-induced oxidative stress and cell death in skin in vitro and in vivo.

    Science.gov (United States)

    Ohba, Takuya; Ishisaka, Mitsue; Tsujii, Saori; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Kubo, Koya; Umigai, Naofumi; Iwawaki, Takao; Hara, Hideaki

    2016-10-15

    Crocetin, the aglycone of crocin, is a carotenoid found in fruits of gardenia (Gardeina jasminoides Ellis) and saffron (Crocus sativus L.). We investigated the protective effects of crocetin against ultraviolet-A (UV-A)-induced skin damage and explored the underlying mechanism. Human skin-derived fibroblasts cells (NB1-RGB) were damaged by exposure to UV-A irradiation (10J/cm(2)). Crocetin protected these cells against cell death and reduced the production of reactive oxygen species induced by UV-A irradiation. Crocetin treatment also suppressed induction of caspase-3 activation by UV-A irradiation. The effects of crocetin against oxidative stress were also examined by imaging of Keap1-dependent oxidative stress detector (OKD) mice. UV-A irradiation upregulated oxidative stress in the OKD mice skin, while crocetin administration (100mg/kg, p.o.) ameliorated this oxidative stress. Crocetin administration also decreased lipid peroxidation in the skin. These findings suggest that crocetin its observed protective effects against UV-A induced skin damage by reducing reactive oxygen species production and cell apoptosis.

  15. Early activation of lipoxygenase in lentil (Lens culinaris) root protoplasts by oxidative stress induces programmed cell death

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Maccarrone, M.; Zadelhoff, G. van; Veldink, G.A.; Finazzi Agrò, A.

    2000-01-01

    Oxidative stress caused by hydrogen peroxide (H2O2) triggers the hypersensitive response of plants to pathogens. Here, short pulses of H2O2 are shown to cause death of lentil (Lens culinaris) root protoplasts. Dead cells showed DNA fragmentation and ladder formation, typical hallmarks of apoptosis (

  16. Changes and significances of islet β-cell function, oxidative stress and adipocyte factor in gestational diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Guang-Yu Sun

    2016-01-01

    Objective:To investigate the changes and significances of islet β-cell function, oxidative stress and adipocyte factor in gestational diabetes mellitusthe. Methods:A total of 60 cases of gestational diabetes mellitus (GDM) patients were regarded as GDM group, a total of 60 cases of normal pregnant women were regarded as pregnant group, and a total of 60 cases of healthy women were regarded as control group. Isletβ-cell function, oxidative stress and adipocyte factor were measured and compared in the three groups. Results:For isletβ-cell function, the levels of FBG, FINS and HOMA-IR in GDM group significantly increased and the levels of HOMA-β and ISI in GDM group significantly decreased compared with control group and pregnant group. For oxidative stress, the level of MDA in GDM group significantly increased and the levels of SOD, GSH and TAOC in GDM group significantly decreased compared with control group and pregnant group. For adipocyte factor, the levels of adiponectin and visfatin in GDM group significantly decreased and the levels of leptin and resistin in GDM group significantly increased compared with control group and pregnant group. Conclusion:Gestational diabetes mellitus could result in impairment of islet β-cell function, decrease of insulin, oxidative stress and abnormality of adipocyte factor .

  17. Streptozotocin-Induced Cytotoxicity, Oxidative Stress and Mitochondrial Dysfunction in Human Hepatoma HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Haider Raza

    2012-05-01

    Full Text Available Streptozotocin (STZ is an antibiotic often used in the treatment of different types of cancers. It is also highly cytotoxic to the pancreatic beta-cells and therefore is commonly used to induce experimental type 1 diabetes in rodents. Resistance towards STZ-induced cytotoxicity in cancer cells has also been reported. Our previous studies have reported organ-specific toxicity and metabolic alterations in STZ-induced diabetic rats. STZ induces oxidative stress and metabolic complications. The precise molecular mechanism of STZ-induced toxicity in different tissues and carcinomas is, however, unclear. We have, therefore, investigated the mechanism of cytotoxicity of STZ in HepG2 hepatoma cells in culture. Cells were treated with different doses of STZ for various time intervals and the cytotoxicity was studied by observing the alterations in oxidative stress, mitochondrial redox and metabolic functions. STZ induced ROS and RNS formation and oxidative stress as measured by an increase in the lipid peroxidation as well as alterations in the GSH-dependent antioxidant metabolism. The mitochondria appear to be a highly sensitive target for STZ toxicity. The mitochondrial membrane potential and enzyme activities were altered in STZ treated cells resulting in the inhibition of ATP synthesis. ROS-sensitive mitochondrial aconitase activity was markedly inhibited suggesting increased oxidative stress in STZ-induced mitochondrial toxicity. These results suggest that STZ-induced cytotoxicity in HepG2 cells is mediated, at least in part, by the increase in ROS/RNS production, oxidative stress and mitochondrial dysfunction. Our study may be significant for better understanding the mechanisms of STZ action in chemotherapy and drug induced toxicity.

  18. Cytotoxic effects of incense particles in relation to oxidative stress, the cell cycle and F-actin assembly.

    Science.gov (United States)

    Chuang, Hsiao-Chi; Jones, Tim; Chen, Tzu-Tao; BéruBé, Kelly

    2013-07-18

    Epidemiological studies have suggested that combustion-derived smoke, such as that produced during incense burning, is a deleterious air pollutant. It is capable of initiating oxidative stress and mutation; however, the related apoptotic processes remain unclear. In order to elucidate the biological mechanisms of reactive oxygen species (ROS)-induced respiratory toxicology, alveolar epithelial A549 cells were exposed to incense particulate matter (PM), with and without antioxidant N-acetyl-l-cysteine (NAC). The cross-linking associations between oxidative capacity, cell cycle events, actin cytoskeletal dynamics and intracellular calcium signals were investigated. An incense PM suspension caused significant oxidative stress in A549 cells, as shown by inhibition of the cell cycle at G1 and G2/M check-points, and the induction of apoptosis at Sub-G1. At the same time, alterations in the F-actin filamentous assemblies were observed. The levels of intracellular Ca(2+) were increased after incense PM exposure. Antioxidant NAC treatment revealed that oxidative stress and F-actin remodelling was significantly mitigated. This suggests that ROS accumulation could alter cell cycle regulation and anomalous remodelling of the cortical cytoskeleton that allowed impaired cells to enter into apoptosis. This study has elucidated the integral patho-physiological interactions of incense PM and the potential mechanisms for the development of ROS-driven respiratory impairment.

  19. Isocitrate dehydrogenase 1 mutant R132H sensitizes glioma cells to BCNU-induced oxidative stress and cell death.

    Science.gov (United States)

    Mohrenz, Isabelle Vanessa; Antonietti, Patrick; Pusch, Stefan; Capper, David; Balss, Jörg; Voigt, Sophia; Weissert, Susanne; Mukrowsky, Alicia; Frank, Jan; Senft, Christian; Seifert, Volker; von Deimling, Andreas; Kögel, Donat

    2013-11-01

    Isocitrate dehydrogenase 1 (IDH1) decarboxylates isocitrate to α-ketoglutarate (α-KG) leading to generation of NADPH, which is required to regenerate reduced glutathione (GSH), the major cellular ROS scavenger. Mutation of R132 of IDH1 abrogates generation of α-KG and leads to conversion of α-KG to 2-hydroxyglutarate. We hypothesized that glioma cells expressing mutant IDH1 have a diminished antioxidative capacity and therefore may encounter an ensuing loss of cytoprotection under conditions of oxidative stress. Our study was performed with LN229 cells stably overexpressing IDH1 R132H and wild type IDH1 or with a lentiviral IDH1 knockdown. Quantification of GSH under basal conditions and following treatment with the glutathione reductase inhibitor BCNU revealed significantly lower GSH levels in IDH1 R132H expressing cells and IDH1 KD cells compared to their respective controls. FACS analysis of cell death and ROS production also demonstrated an increased sensitivity of IDH1-R132H-expressing cells and IDH1 KD cells to BCNU, but not to temozolomide. The sensitivity of IDH1-R132H-expressing cells and IDH1 KD cells to ROS induction and cell death was further enhanced with the transaminase inhibitor aminooxyacetic acid and under glutamine free conditions, indicating that these cells were more addicted to glutaminolysis. Increased sensitivity to BCNU-induced ROS production and cell death was confirmed in HEK293 cells inducibly expressing the IDH1 mutants R132H, R132C and R132L. Based on these findings we propose that in addition to its established pro-tumorigenic effects, mutant IDH1 may also limit the resistance of gliomas to specific death stimuli, therefore opening new perspectives for therapy.

  20. HDAC2 selectively regulates FOXO3a-mediated gene transcription during oxidative stress-induced neuronal cell death.

    Science.gov (United States)

    Peng, Shengyi; Zhao, Siqi; Yan, Feng; Cheng, Jinbo; Huang, Li; Chen, Hong; Liu, Qingsong; Ji, Xunming; Yuan, Zengqiang

    2015-01-21

    All neurodegenerative diseases are associated with oxidative stress-induced neuronal death. Forkhead box O3a (FOXO3a) is a key transcription factor involved in neuronal apoptosis. However, how FOXO3a forms complexes and functions in oxidative stress processing remains largely unknown. In the present study, we show that histone deacetylase 2 (HDAC2) forms a physical complex with FOXO3a, which plays an important role in FOXO3a-dependent gene transcription and oxidative stress-induced mouse cerebellar granule neuron (CGN) apoptosis. Interestingly, we also found that HDAC2 became selectively enriched in the promoter region of the p21 gene, but not those of other target genes, and inhibited FOXO3a-mediated p21 transcription. Furthermore, we found that oxidative stress reduced the interaction between FOXO3a and HDAC2, leading to an increased histone H4K16 acetylation level in the p21 promoter region and upregulated p21 expression in a manner independent of p53 or E2F1. Phosphorylation of HDAC2 at Ser 394 is important for the HDAC2-FOXO3a interaction, and we found that cerebral ischemia/reperfusion reduced phosphorylation of HDAC2 at Ser 394 and mitigated the HDAC2-FOXO3a interaction in mouse brain tissue. Our study reveals the novel regulation of FOXO3a-mediated selective gene transcription via epigenetic modification in the process of oxidative stress-induced cell death, which could be exploited therapeutically.

  1. Expression of PUMA in Follicular Granulosa Cells Regulated by FoxO1 Activation During Oxidative Stress.

    Science.gov (United States)

    Liu, Ze-Qun; Shen, Ming; Wu, Wang-Jun; Li, Bo-Jiang; Weng, Qian-Nan; Li, Mei; Liu, Hong-Lin

    2015-06-01

    Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced granulosa cell (GC) apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. In this study, we found expression of the p53-upregulated modulator of apoptosis (PUMA), a BH3-only Bcl-2 subfamily protein, in ovarian GCs during oxidative stress. By overexpression and knockdown of Forkhead box O1 (FoxO1), we found that FoxO1 regulates PUMA at the protein level. Moreover, as c-Jun N-terminal kinase (JNK) has been shown to activate FoxO1 by promoting its nuclear import, we used a JNK inhibitor to reduce FoxO1 activation and detected decreased PUMA messenger RNA expression and protein levels during oxidative stress. In addition, in vivo oxidative stress-induced upregulation of PUMA was found following injection of 3 nitropropionic acid in mice. In conclusion, oxidative stress increases PUMA expression regulated by FoxO1 in follicular GCs.

  2. Effect of patchouli alcohol on the regulation of heat shock-induced oxidative stress in IEC-6 cells.

    Science.gov (United States)

    Liu, Xiaoxi; Jiang, Linshu; Liu, Fenghua; Chen, Yuping; Xu, Lei; Li, Deyin; Ma, Yunfei; Li, Huanrong; Xu, Jianqin

    2016-08-01

    Purpose Patchouli alcohol (PA) is used to treat gastrointestinal dysfunction. The purpose of this study was to ascertain the function of PA in the regulated process of oxidative stress in rat intestinal epithelial cells (IEC-6). Materials and methods Oxidative stress was stimulated by exposing IEC-6 cells to heat shock (42 °C for 3 h). IEC-6 cells in treatment groups were pretreated with various concentrations of PA (10, 40, and 80 ng/mL) for 3 h before heat shock. Results Heat shock caused damage to the morphology of IEC-6 cells, and increased reactive oxygen species (ROS) level and malondialdehyde (MDA) content. Moreover, mRNA and protein expression by target genes related to oxidative stress in heat shock were also altered. Specifically, the mRNA expression by HSP70, HSP90, GSH-px, NRF2 nd HO-1were all increased, and Nrf2 and Keap1 protein expression were increased after heat shock. However, pretreatment with PA weakened the level of damage to the cellular morphology, and decreased the MDA content caused by heat shock, indicating PA had cytoprotective activities. Pretreatment with PA at high dose significantly increased generation of intracellular ROS. Compared with the heat shock group alone, PA pretreatment significantly decreased the mRNA expression by HSP70, HSP90, SOD, CAT, GSH-px, KEAP1 and HO-1. Furthermore, the high dose of PA significantly increased Nrf2 protein expression, while both the intermediate and high dose of PA significantly increased HO-1 protein expression. Conclusion Heat-shock-induced oxidative stress in IEC-6 cells, and PA could alleviate the Nrf2-Keap1 cellular oxidative stress responses.

  3. Acute Activation of Oxidative Pentose Phosphate Pathway as First-Line Response to Oxidative Stress in Human Skin Cells.

    Science.gov (United States)

    Kuehne, Andreas; Emmert, Hila; Soehle, Joern; Winnefeld, Marc; Fischer, Frank; Wenck, Horst; Gallinat, Stefan; Terstegen, Lara; Lucius, Ralph; Hildebrand, Janosch; Zamboni, Nicola

    2015-08-01

    Integrity of human skin is endangered by exposure to UV irradiation and chemical stressors, which can provoke a toxic production of reactive oxygen species (ROS) and oxidative damage. Since oxidation of proteins and metabolites occurs virtually instantaneously, immediate cellular countermeasures are pivotal to mitigate the negative implications of acute oxidative stress. We investigated the short-term metabolic response in human skin fibroblasts and keratinocytes to H2O2 and UV exposure. In time-resolved metabolomics experiments, we observed that within seconds after stress induction, glucose catabolism is routed to the oxidative pentose phosphate pathway (PPP) and nucleotide synthesis independent of previously postulated blocks in glycolysis (i.e., of GAPDH or PKM2). Through ultra-short (13)C labeling experiments, we provide evidence for multiple cycling of carbon backbones in the oxidative PPP, potentially maximizing NADPH reduction. The identified metabolic rerouting in oxidative and non-oxidative PPP has important physiological roles in stabilization of the redox balance and ROS clearance.

  4. Pycnogenol modulates apoptosis by suppressing oxidative stress and inflammation in high glucose-treated renal tubular cells.

    Science.gov (United States)

    Kim, You Jung; Kim, Young Ae; Yokozawa, Takako

    2011-09-01

    Compelling evidence indicates that polyphenolic antioxidants protect against diabetic nephropathy. Pycnogenol is made up of flavonoids, mainly procyanidins and phenolic compounds, and is a known powerful antioxidant. Hyperglycemia is characteristic of diabetic nephropathy and induces renal tubular cell apoptosis. Thus, in this study, we used high glucose-treated renal tubular cells to investigate the protective action of pycnogenol against high glucose-induced apoptosis and diabetic nephropathy. We also sought to further delineate the underlying mechanisms elicited by oxidative stress and inflammation and suppressed by pycnogenol. Results show that pycnogenol significantly suppressed the high glucose-induced morphological changes and the reduction in cell viability associated with cytotoxicity. Bcl2/Bax protein levels indicated pycnogenol's anti-apoptotic effect against high glucose-induced apoptotic cell death. In addition, several key markers of oxidative stress and inflammation were measured for pycnogenol's beneficial effects. Results indicate pycnogenol's anti-oxidative and anti-inflammatory efficacy in suppressing lipid peroxidation, total reactive species (RS), superoxide ((·)O(2)), nitric oxide (NO(·)), peroxynitrite (ONOO(-)), pro-inflammatory inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) nuclear translocation. Based on these results, we conclude that pycnogenol's anti-oxidative and anti-inflammatory properties underlie its anti-apoptotic effects, suggesting further investigation of pycnogenol as a promising treatment against diabetic nephropathy.

  5. Erythropoietin employs cell longevity pathways of SIRT1 to foster endothelial vascular integrity during oxidant stress.

    Science.gov (United States)

    Hou, Jinling; Wang, Shaohui; Shang, Yan Chen; Chong, Zhao Zhong; Maiese, Kenneth

    2011-08-01

    Given the cytoprotective ability of erythropoietin (EPO) in cerebral microvascular endothelial cells (ECs) and the invaluable role of ECs in the central nervous system, it is imperative to elucidate the cellular pathways for EPO to protect ECs against brain injury. Here we illustrate that EPO relies upon the modulation of SIRT1 (silent mating type information regulator 2 homolog 1) in cerebral microvascular ECs to foster cytoprotection during oxygen-glucose deprivation (OGD). SIRT1 activation which results in the inhibition of apoptotic early membrane phosphatidylserine (PS) externalization and subsequent DNA degradation during OGD becomes a necessary component for EPO protection in ECs, since inhibition of SIRT1 activity or diminishing its expression by gene silencing abrogates cell survival supported by EPO during OGD. Furthermore, EPO promotes the subcellular trafficking of SIRT1 to the nucleus which is necessary for EPO to foster vascular protection. EPO through SIRT1 averts apoptosis through activation of protein kinase B (Akt1) and the phosphorylation and cytoplasmic retention of the forkhead transcription factor FoxO3a. SIRT1 through EPO activation also utilizes mitochondrial pathways to prevent mitochondrial depolarization, cytochrome c release, and Bad, caspase 1, and caspase 3 activation. Our work identifies novel pathways for EPO in the vascular system that can govern the activity of SIRT1 to prevent apoptotic injury through Akt1, FoxO3a phosphorylation and trafficking, mitochondrial membrane permeability, Bad activation, and caspase 1 and 3 activities in ECs during oxidant stress.

  6. Oxidative stress-induced DNA damage in the synovial cells of the temporomandibular joint in the rat.

    Science.gov (United States)

    Yamaza, T; Masuda, K F; Atsuta, I; Nishijima, K; Kido, M A; Tanaka, T

    2004-08-01

    Synovial hyperplasia is a feature of degenerative temporomandibular joint (TMJ) disease. However, the mechanism by which hyperplasia progresses in the TMJ is unknown. Based on the hypothesis that the oxidative stress generated by mechanical loading causes degenerative changes in the TMJ synovium, we investigated the generation of the highly reactive species, peroxynitrite, and the occurrence of DNA damage in the synovium. After condylar hypermobility of rat TMJs, a marker of peroxynitrite, nitrotyrosine, was localized to the nuclei and cytoplasm of the synovial lining cells and fibroblasts in synovitis-induced TMJ. DNA single-strand breaks were found in the nuclei of the synovial cells only after enzyme treatment, whereas DNA double-strand breaks were not detected. These findings indicate that condylar hypermovement induces the proliferation of synovial cells, and suggest that oxidative stress leads to the progression of synovial hyperplasia via DNA damage of the synovial cells in TMJs after mechanical loading.

  7. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells.

    Science.gov (United States)

    Sawa, Kenta; Uematsu, Takumi; Korenaga, Yusuke; Hirasawa, Ryuya; Kikuchi, Masatoshi; Murata, Kyohei; Zhang, Jian; Gai, Xiaoqing; Sakamoto, Kazuichi; Koyama, Tomoyuki; Satoh, Takumi

    2017-03-16

    Krebs cycle intermediates (KCIs) are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2',7'-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs-used at 1 mM-protected against cell death induced by high concentrations of glutamate-another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM), they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  8. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells

    Directory of Open Access Journals (Sweden)

    Kenta Sawa

    2017-03-01

    Full Text Available Krebs cycle intermediates (KCIs are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2′,7′-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs—used at 1 mM—protected against cell death induced by high concentrations of glutamate—another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM, they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  9. NKT cell modulates NAFLD potentiation of metabolic oxidative stress-induced mesangial cell activation and proximal tubular toxicity

    Science.gov (United States)

    Alhasson, Firas; Dattaroy, Diptadip; Das, Suvarthi; Chandrashekaran, Varun; Seth, Ratanesh Kumar; Schnellmann, Rick G.

    2015-01-01

    Obesity and nonalcoholic fatty liver disease (NAFLD) are associated with the development and progression of chronic kidney disease. We recently showed that NAFLD induces liver-specific cytochrome P-450 (CYP)2E1-mediated metabolic oxidative stress after administration of the CYP2E1 substrate bromodichloromethane (BDCM) (Seth RK, Das S, Kumar A, Chanda A, Kadiiska MB, Michelotti G, Manautou J, Diehl AM, Chatterjee S. Toxicol Appl Pharmacol 274: 42–54, 2014; Seth RK, Kumar A, Das S, Kadiiska MB, Michelotti G, Diehl AM, Chatterjee S. Toxicol Sci 134:291–303, 2013). The present study examined the effects of CYP2E1-mediated oxidative stress in NAFLD leading to kidney toxicity. Mice were fed a high-fat diet for 12 wk to induce NAFLD. NAFLD mice were exposed to BDCM, a CYP2E1 substrate, for 4 wk. NAFLD + BDCM increased CYP2E1-mediated lipid peroxidation in proximal tubular cells compared with mice with NAFLD alone or BDCM-treated lean mice, thus ruling out the exclusive role of BDCM. Lipid peroxidation increased IL-1β, TNF-α, and interferon-γ. In parallel, mesangial cell activation was observed by increased α-smooth muscle actin and transforming growth factor-β, which was blocked by the CYP2E1 inhibitor diallyl sulphide both in vivo and in vitro. Mice lacking natural killer T cells (CD1d knockout mice) showed elevated (>4-fold) proinflammatory mediator release, increased Toll-like receptor (TLR)4 and PDGF2 mRNA, and mesangial cell activation in the kidney. Finally, NAFLD CD1D knockout mice treated with BDCM exhibited increased high mobility group box 1 and Fas ligand levels and TUNEL-positive nuclei, indicating that higher cell death was attenuated in TLR4 knockout mice. Tubular cells showed increased cell death and cytokine release when incubated with activated mesangial cells. In summary, an underlying condition of progressive NAFLD causes renal immunotoxicity and aberrant glomerular function possibly through high mobility group box 1-dependent TLR4 signaling

  10. 3',4',7-Trihydroxyflavone prevents apoptotic cell death in neuronal cells from hydrogen peroxide-induced oxidative stress.

    Science.gov (United States)

    Kwon, Seung-Hwan; Hong, Sa-Ik; Ma, Shi-Xun; Lee, Seok-Yong; Jang, Choon-Gon

    2015-06-01

    In this study, we investigated the mechanisms of 3',4',7-trihydroxyflavone (THF) protection of neuronal cells from neuronal cell death induced by the oxidative stress-related neurotoxin hydrogen peroxide (H2O2). Pretreatment with THF significantly elevated cell viability, reduced H2O2-induced lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) production, glutathione (GSH) content, superoxide dismutase (SOD) activity, catalase (CAT) activity, and mitochondria membrane potential (MMP) loss. Western blot data demonstrated that THF inhibited the H2O2-induced up- or down-regulation of cleaved caspase-3, cleaved caspase-9, cleaved poly-ADP-ribose polymerase (PARP), Bax, Bcl-2, and Bcl-xL, and attenuated the H2O2-induced release of cytochrome c from the mitochondria to the cytosol. In addition, pretreatment with THF attenuated H2O2-induced rapid and significant phosphorylation of c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinases (PI3K)/Akt. THF also inhibited nuclear factor-κB (NF-κB) translocation to the nucleus induced by H2O2, down-stream of H2O2-induced phosphorylation of MAPKs and PI3K/Akt. These data provide the first evidence that THF protects neuronal cells against H2O2-induced oxidative stress, possibly through ROS reduction, mitochondria protection, and NF-κB modulation via MAPKs and PI3K/Akt pathways. The neuroprotective effects of THF make it a promising candidate as a therapeutic agent for neurodegenerative diseases.

  11. Cytotoxicity, oxidative stress, and genotoxicity in human hepatocyte and embryonic kidney cells exposed to ZnO nanoparticles

    Science.gov (United States)

    Guan, Rongfa; Kang, Tianshu; Lu, Fei; Zhang, Zhiguo; Shen, Haitao; Liu, Mingqi

    2012-10-01

    Traces of zinc oxide nanoparticles (ZnO NPs) used may be found in the liver and kidney. The aim of this study is to determine the optimal viability assay for using with ZnO NPs and to assess their toxicity to human hepatocyte (L02) and human embryonic kidney (HEK293) cells. Cellular morphology, mitochondrial function (MTT assay), and oxidative stress markers (malondialdehyde, glutathione (GSH) and superoxide dismutase (SOD)) were assessed under control and exposed to ZnO NPs conditions for 24 h. The results demonstrated that ZnO NPs lead to cellular morphological modifications, mitochondrial dysfunction, and cause reduction of SOD, depletion of GSH, and oxidative DNA damage. The exact mechanism behind ZnO NPs toxicity suggested that oxidative stress and lipid peroxidation played an important role in ZnO NPs-elicited cell membrane disruption, DNA damage, and subsequent cell death. Our preliminary data suggested that oxidative stress might contribute to ZnO NPs cytotoxicity.

  12. A newly identified essential complex, Dre2-Tah18, controls mitochondria integrity and cell death after oxidative stress in yeast.

    Directory of Open Access Journals (Sweden)

    Laurence Vernis

    Full Text Available A mutated allele of the essential gene TAH18 was previously identified in our laboratory in a genetic screen for new proteins interacting with the DNA polymerase delta in yeast [1]. The present work shows that Tah18 plays a role in response to oxidative stress. After exposure to lethal doses of H(2O(2, GFP-Tah18 relocalizes to the mitochondria and controls mitochondria integrity and cell death. Dre2, an essential Fe/S cluster protein and homologue of human anti-apoptotic Ciapin1, was identified as a molecular partner of Tah18 in the absence of stress. Moreover, Ciapin1 is able to replace yeast Dre2 in vivo and physically interacts with Tah18. Our results are in favour of an oxidative stress-induced cell death in yeast that involves mitochondria and is controlled by the newly identified Dre2-Tah18 complex.

  13. Inhibition of DNA methyltransferase or histone deacetylase protects retinal pigment epithelial cells from DNA damage induced by oxidative stress by the stimulation of antioxidant enzymes.

    Science.gov (United States)

    Tokarz, Paulina; Kaarniranta, Kai; Blasiak, Janusz

    2016-04-05

    Epigenetic modifications influence DNA damage response (DDR). In this study we explored the role of DNA methylation and histone acetylation in DDR in cells challenged with acute or chronic oxidative stress. We used retinal pigment epithelial cells (ARPE-19), which natively are exposed to oxidative stress due to permanent exposure to light and high blood flow. We employed a DNA methyltransferase inhibitor - RG108 (RG), or a histone deacetylase inhibitor - valproic acid (VA). ARPE-19 cells were exposed to tert-butyl hydroperoxide, an acute oxidative stress inducer, or glucose oxidase, which slowly liberates low-doses of hydrogen peroxide in the presence of glucose, creating chronic conditions. VA and RG reduced level of intracellular reactive oxygen species and DNA damage in ARPE-19 cells in normal condition and in oxidative stress. This protective effect of VA and RG was associated with the up-regulated expression of antioxidant enzyme genes: CAT, GPx1, GPx4, SOD1 and SOD2. RG decreased the number of cells in G2/M checkpoint in response to chronic oxidative stress. Neither RG nor VA changed the DNA repair or apoptosis induced by oxidative stress. Therefore, certain epigenetic manipulations may protect ARPE-19 cells from detrimental effects of oxidative stress by modulation of antioxidative enzyme gene expression, which may be further explored in pharmacological studies on oxidative stress-related eye diseases.

  14. Dietary oxidized n-3 PUFA induce oxidative stress and inflammation: role of intestinal absorption of 4-HHE and reactivity in intestinal cells.

    Science.gov (United States)

    Awada, Manar; Soulage, Christophe O; Meynier, Anne; Debard, Cyrille; Plaisancié, Pascale; Benoit, Bérengère; Picard, Grégory; Loizon, Emmanuelle; Chauvin, Marie-Agnès; Estienne, Monique; Peretti, Noël; Guichardant, Michel; Lagarde, Michel; Genot, Claude; Michalski, Marie-Caroline

    2012-10-01

    Dietary intake of long-chain n-3 PUFA is now widely advised for public health and in medical practice. However, PUFA are highly prone to oxidation, producing potentially deleterious 4-hydroxy-2-alkenals. Even so, the impact of consuming oxidized n-3 PUFA on metabolic oxidative stress and inflammation is poorly described. We therefore studied such effects and hypothesized the involvement of the intestinal absorption of 4-hydroxy-2-hexenal (4-HHE), an oxidized n-3 PUFA end-product. In vivo, four groups of mice were fed for 8 weeks high-fat diets containing moderately oxidized or unoxidized n-3 PUFA. Other mice were orally administered 4-HHE and euthanized postprandially versus baseline mice. In vitro, human intestinal Caco-2/TC7 cells were incubated with 4-hydroxy-2-alkenals. Oxidized diets increased 4-HHE plasma levels in mice (up to 5-fold, P intestine along with decreasing Paneth cell number (up to -19% in the duodenum). Both in vivo and in vitro, intestinal absorption of 4-HHE was associated with formation of 4-HHE-protein adducts and increased expression of glutathione peroxidase 2 (GPx2) and glucose-regulated protein 78 (GRP78). Consumption of oxidized n-3 PUFA results in 4-HHE accumulation in blood after its intestinal absorption and triggers oxidative stress and inflammation in the upper intestine.

  15. Oxidative Stress and Neurodegenerative Disorders

    Directory of Open Access Journals (Sweden)

    Jie Li

    2013-12-01

    Full Text Available Living cells continually generate reactive oxygen species (ROS through the respiratory chain during energetic metabolism. ROS at low or moderate concentration can play important physiological roles. However, an excessive amount of ROS under oxidative stress would be extremely deleterious. The central nervous system (CNS is particularly vulnerable to oxidative stress due to its high oxygen consumption, weakly antioxidative systems and the terminal-differentiation characteristic of neurons. Thus, oxidative stress elicits various neurodegenerative diseases. In addition, chemotherapy could result in severe side effects on the CNS and peripheral nervous system (PNS of cancer patients, and a growing body of evidence demonstrates the involvement of ROS in drug-induced neurotoxicities as well. Therefore, development of antioxidants as neuroprotective drugs is a potentially beneficial strategy for clinical therapy. In this review, we summarize the source, balance maintenance and physiologic functions of ROS, oxidative stress and its toxic mechanisms underlying a number of neurodegenerative diseases, and the possible involvement of ROS in chemotherapy-induced toxicity to the CNS and PNS. We ultimately assess the value for antioxidants as neuroprotective drugs and provide our comments on the unmet needs.

  16. Oxidative stress & male infertility.

    Science.gov (United States)

    Makker, Kartikeya; Agarwal, Ashok; Sharma, Rakesh

    2009-04-01

    The male factor is considered a major contributory factor to infertility. Apart from the conventional causes for male infertility such as varicocoele, cryptorchidism, infections, obstructive lesions, cystic fibrosis, trauma, and tumours, a new and important cause has been identified: oxidative stress. Oxidative stress is a result of the imbalance between reactive oxygen species (ROS) and antioxidants in the body. It is a powerful mechanism that can lead to sperm damage, deformity and eventually, male infertility. This review discusses the physiological need for ROS and their role in normal sperm function. It also highlights the mechanism of production and the pathophysiology of ROS in relation to the male reproductive system and enumerate the benefits of incorporating antioxidants in clinical and experimental settings.

  17. Flavonoid Fraction of Orange and Bergamot Juices Protect Human Lung Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Stress

    OpenAIRE

    Nadia Ferlazzo; Giuseppa Visalli; Antonella Smeriglio; Santa Cirmi; Giovanni Enrico Lombardo; Pietro Campiglia; Angela Di Pietro; Michele Navarra

    2015-01-01

    It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of bo...

  18. Oxidative stress in HEp-2 human laryngeal carcinoma cells induced by combination of vitamins B12b and C.

    Science.gov (United States)

    Akatov, V S; Solov'eva, M E; Leshchenko, V V; Teplova, V V

    2003-09-01

    Incubation of human laryngeal epidermoid carcinoma HEp-2 cells with hydroxocobalamin (vitamin B12b) and ascorbic acid (vitamin C) for 1 h initiated oxidative stress accompanied by damage to mitochondria and increase in intracellular oxidative activity. Studies of the kinetics of these processes showed that the increase in intracellular H2O2 activity and mitochondrial damage are more likely a result, but not the cause of cell apoptosis during the first hour of their incubation with vitamins B12b and C.

  19. Protective Effects of Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) Against Oxidative Stress in Zebrafish Hair Cells.

    Science.gov (United States)

    Kasica, Natalia; Podlasz, Piotr; Sundvik, Maria; Tamas, Andrea; Reglodi, Dora; Kaleczyc, Jerzy

    2016-11-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic neuropeptide, with known antiapoptotic functions. Our previous in vitro study has demonstrated the ameliorative role of PACAP-38 in chicken hair cells under oxidative stress conditions, but its effects on living hair cells is now yet known. Therefore, the aim of the present study was to investigate in vivo the protective role of PACAP-38 in hair cells found in zebrafish (Danio rerio) sense organs-neuromasts. To induce oxidative stress the 5-day postfertilization (dpf) zebrafish larvae were exposed to 1.5 mM H2O2 for 15 min or 1 h. This resulted in an increase in caspase-3 and p-38 MAPK level in the hair cells as well as in an impairment of the larvae basic behavior. To investigate the ameliorative role of PACAP-38, the larvae were incubated with a mixture of 1.5 mM H2O2 and 100 nM PACAP-38 following 1 h preincubation with 100 nM PACAP-38 only. PACAP-38 abilities to prevent hair cells from apoptosis were investigated. Whole-mount immunohistochemistry and confocal microscopy analyses revealed that PACAP-38 treatment decreased the cleaved caspase-3 level in the hair cells, but had no influence on p-38 MAPK. The analyses of basic locomotor activity supported the protective role of PACAP-38 by demonstrating the improvement of the fish behavior after PACAP-38 treatment. In summary, our in vivo findings demonstrate that PACAP-38 protects zebrafish hair cells from oxidative stress by attenuating oxidative stress-induced apoptosis.

  20. Hemoglobin oxidative stress in cancer.

    Science.gov (United States)

    Della Rovere, F; Granata, A; Broccio, M; Zirilli, A; Broccio, G

    1995-01-01

    The role played by free radicals in carcinogenesis and their relationships with antioxidant pool and cancer have already been shown. Free radicals induce increased membrane permeability through membrane lipid peroxidation, protein oxidation and histamine release from mast cells. Free radicals also cause oxyhemoglobin oxidative stress which increases methemoglobin and hemichromes. For this reason, we studied the in vitro formation of methemoglobin at 0' and 90', dosed following the HPLC method, after oxidative stress of blood by means of acetylphenylhydrazine in 40 subjects with cancer and 40 healthy donors. The results showed that methemoglobin formation was highly significant in tumors as compared to controls (P < 0.0001). The statistical analyses we carried out showed that metHb formation is not affected by age, sex, smoking habit, red blood cell number, Hb, Ht or tumor staging. This makes us believe that free radicals alter erythrocyte membrane permeability and predenaturate oxyhemoglobin so that erythrocyte membrane becomes more susceptible to new oxidative stress. This caused the abnormal response we found. Our results clearly underline the role played by free radicals in tumorous disease and provide a successful and easy method to detect early, even in a pre-clinical stage, the presence of tumorous alterations in the human body.

  1. Isothiocyanates induce oxidative stress and suppress the metastasis potential of human non-small cell lung cancer cells

    Directory of Open Access Journals (Sweden)

    Zhou Qinghua

    2010-06-01

    Full Text Available Abstract Background Isothiocyanates are natural compounds found in consumable cruciferous vegetables. They have been shown to inhibit chemical carcinogenesis by a wide variety of chemical carcinogens in animal models. Recent studies have also shown that isothiocyanates have antitumor activity, inhibiting the growth of several types of cultured human cancer cells. Our previous study showed that PEITC inhibited human leukemia cells growth by inducing apoptosis. However, the effect of isothiocyanates on lung cancer cell metastasis has not been studied. In the present study, we investigated the inhibitory effects of BITC and PEITC on metastatic potential of highly metastatic human lung cancer L9981 cells. Methods Cell migration and invasion were measured by wound healing assay and transwell chemotaxis assay. Expression of metastasis-related genes was assessed by quantitative RT-PCR and Western blotting. The mechanisms of action were evaluated by flow cytometry, reporter assay and Western blotting. Results Our data showed that both BITC and PEITC inhibited L9981 cell growth in a dose-dependent manner, the IC50 values were 5.0 and 9.7 μM, respectively. Cell migrations were reduced to 8.1% and 16.5% of control, respectively; and cell invasions were reduced to 2.7% and 7.3% of control, respectively. Metastasis-related genes MMP-2, Twist and β-catenin were also modulated. BITC and PEITC inhibited cell survival signaling molecules Akt and NFκB activation. Moreover, BITC and PEITC increased ROS generation and caused GSH depletion. Pretreatment with NAC blocked BITC and PEITC induced ROS elevation and NFκB inhibition. Conclusion Our results indicated that BITC and PEITC suppress lung cancer cell metastasis potential by modulation of metastasis-related gene expression, inhibition of Akt/NFκB pathway. Induction of oxidative stress may play an important role.

  2. Unique role of NADPH oxidase 5 in oxidative stress in human renal proximal tubule cells

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    Peiying Yu

    2014-01-01

    Full Text Available NADPH oxidases are the major sources of reactive oxygen species in cardiovascular, neural, and kidney cells. The NADPH oxidase 5 (NOX5 gene is present in humans but not rodents. Because Nox isoforms in renal proximal tubules (RPTs are involved in the pathogenesis of hypertension, we tested the hypothesis that NOX5 is differentially expressed in RPT cells from normotensive (NT and hypertensive subjects (HT. We found that NOX5 mRNA, total NOX5 protein, and apical membrane NOX5 protein were 4.2±0.7-fold, 5.2±0.7-fold, and 2.8±0.5-fold greater in HT than NT. Basal total NADPH oxidase activity was 4.5±0.2-fold and basal NOX5 activity in NOX5 immunoprecipitates was 6.2±0.2-fold greater in HT than NT (P=<0.001, n=6–14/group. Ionomycin increased total NOX and NOX5 activities in RPT cells from HT (P<0.01, n=4, ANOVA, effects that were abrogated by pre-treatment of the RPT cells with diphenylene-iodonium or superoxide dismutase. Silencing NOX5 using NOX5-siRNA decreased NADPH oxidase activity (−45.1±3.2% vs. mock-siRNA, n=6–8 in HT. D1-like receptor stimulation decreased NADPH oxidase activity to a greater extent in NT (−32.5±1.8% than HT (−14.8±1.8. In contrast to the marked increase in expression and activity of NOX5 in HT, NOX1 mRNA and protein were minimally increased in HT, relative to NT; total NOX2 and NOX4 proteins were not different between HT and NT, while the increase in apical RPT cell membrane NOX1, NOX2, and NOX4 proteins in HT, relative to NT, was much less than those observed with NOX5. Thus, we demonstrate, for the first time, that NOX5 is expressed in human RPT cells and to greater extent than the other Nox isoforms in HT than NT. We suggest that the increased expression of NOX5, which may be responsible for the increased oxidative stress in RPT cells in human essential hypertension, is caused, in part, by a defective renal dopaminergic system.

  3. Overexpression of DNA ligase III in mitochondria protects cells against oxidative stress and improves mitochondrial DNA base excision repair

    DEFF Research Database (Denmark)

    Akbari, Mansour; Keijzers, Guido; Maynard, Scott;

    2014-01-01

    by rotenone. Our results suggest that the amount of DNA ligase III in mitochondria may be critical for cell survival following prolonged oxidative stress, and demonstrate a functional link between mitochondrial DNA damage and repair, cell survival upon oxidative stress, and removal of dysfunctional......Base excision repair (BER) is the most prominent DNA repair pathway in human mitochondria. BER also results in a temporary generation of AP-sites, single-strand breaks and nucleotide gaps. Thus, incomplete BER can result in the generation of DNA repair intermediates that can disrupt mitochondrial...... DNA replication and transcription and generate mutations. We carried out BER analysis in highly purified mitochondrial extracts from human cell lines U2OS and HeLa, and mouse brain using a circular DNA substrate containing a lesion at a specific position. We found that DNA ligation is significantly...

  4. Oxidative stress in myopia.

    Science.gov (United States)

    Francisco, Bosch-Morell; Salvador, Mérida; Amparo, Navea

    2015-01-01

    Myopia affected approximately 1.6 billion people worldwide in 2000, and it is expected to increase to 2.5 billion by 2020. Although optical problems can be corrected by optics or surgical procedures, normal myopia and high myopia are still an unsolved medical problem. They frequently predispose people who have them to suffer from other eye pathologies: retinal detachment, glaucoma, macular hemorrhage, cataracts, and so on being one of the main causes of visual deterioration and blindness. Genetic and environmental factors have been associated with myopia. Nevertheless, lack of knowledge in the underlying physiopathological molecular mechanisms has not permitted an adequate diagnosis, prevention, or treatment to be found. Nowadays several pieces of evidence indicate that oxidative stress may help explain the altered regulatory pathways in myopia and the appearance of associated eye diseases. On the one hand, oxidative damage associated with hypoxia myopic can alter the neuromodulation that nitric oxide and dopamine have in eye growth. On the other hand, radical superoxide or peroxynitrite production damage retina, vitreous, lens, and so on contributing to the appearance of retinopathies, retinal detachment, cataracts and so on. The objective of this review is to suggest that oxidative stress is one of the key pieces that can help solve this complex eye problem.

  5. Oxidative Stress in Myopia

    Directory of Open Access Journals (Sweden)

    Bosch-Morell Francisco

    2015-01-01

    Full Text Available Myopia affected approximately 1.6 billion people worldwide in 2000, and it is expected to increase to 2.5 billion by 2020. Although optical problems can be corrected by optics or surgical procedures, normal myopia and high myopia are still an unsolved medical problem. They frequently predispose people who have them to suffer from other eye pathologies: retinal detachment, glaucoma, macular hemorrhage, cataracts, and so on being one of the main causes of visual deterioration and blindness. Genetic and environmental factors have been associated with myopia. Nevertheless, lack of knowledge in the underlying physiopathological molecular mechanisms has not permitted an adequate diagnosis, prevention, or treatment to be found. Nowadays several pieces of evidence indicate that oxidative stress may help explain the altered regulatory pathways in myopia and the appearance of associated eye diseases. On the one hand, oxidative damage associated with hypoxia myopic can alter the neuromodulation that nitric oxide and dopamine have in eye growth. On the other hand, radical superoxide or peroxynitrite production damage retina, vitreous, lens, and so on contributing to the appearance of retinopathies, retinal detachment, cataracts and so on. The objective of this review is to suggest that oxidative stress is one of the key pieces that can help solve this complex eye problem.

  6. Olive oil hydroxytyrosol reduces toxicity evoked by acrylamide in human Caco-2 cells by preventing oxidative stress.

    Science.gov (United States)

    Rodríguez-Ramiro, Ildefonso; Martín, María Ángeles; Ramos, Sonia; Bravo, Laura; Goya, Luis

    2011-10-09

    Humans are exposed to dietary acrylamide (AA) during their lifetime, it is therefore necessary to investigate the mechanisms associated with AA-induced toxic effects. Accumulating evidence indicates that oxidative stress contributes to AA cytotoxicity, thus, dietary antioxidants might have a protective role in colonic cells against AA toxicity. We have recently reported that hydroxytyrosol (HTy), a natural antioxidant abundant in olive oil, is able to enhance the cellular antioxidant defence capacity, thereby protecting cells from oxidative stress. In this study, we evaluate the protective role of HTy on alterations of the redox balance induced by AA in Caco-2 intestinal cells. AA cytotoxicity was counteracted by HTy by powerfully reducing ROS generation, recovering the excited enzyme antioxidant defences and decreasing phospho-Jun kinase concentration and caspase-3 activity induced by AA. Therefore, AA-induced cytotoxicity and apoptosis are closely related to oxidative stress in Caco-2 cells and the olive oil natural dietary antioxidant HTy was able to contain AA toxicity by improving the redox status of Caco-2 cells and by partly restraining the apoptotic pathway activated by AA.

  7. Antioxidant effect of mogrosides against oxidative stress induced by palmitic acid in mouse insulinoma NIT-1 cells.

    Science.gov (United States)

    Xu, Q; Chen, S Y; Deng, L D; Feng, L P; Huang, L Z; Yu, R R

    2013-11-18

    Excessive oxidative stress in pancreatic β cells, caused by glucose and fatty acids, is associated with the pathogenesis of type 2 diabetes. Mogrosides have shown antioxidant and antidiabetic activities in animal models of diabetes, but the underlying mechanisms remain unclear. This study evaluated the antioxidant effect of mogrosides on insulinoma cells under oxidative stress caused by palmitic acid, and investigated the underlying molecular mechanisms. Mouse insulinoma NIT-1 cells were cultured in medium containing 0.75 mM palmitic acid, mimicking oxidative stress. The effects of 1 mM mogrosides were determined with the dichlorodihydrofluorescein diacetate assay for intracellular reactive oxygen species (ROS) and FITC-Annexin V/PI assay for cell apoptosis. Expression of glucose transporter-2 (GLUT2) and pyruvate kinase was determined by semi-quantitative reverse-transcription polymerase chain reaction. Palmitic acid significantly increased intracellular ROS concentration 2-fold (Ppalmitic acid, co-treatment with 1 mM mogrosides for 48 h significantly reduced intracellular ROS concentration and restored mRNA expression levels of GLUT2 and pyruvate kinase. However, mogrosides did not reverse palmitic acid-induced apoptosis in NIT-1 cells. Our results indicate that mogrosides might exert their antioxidant effect by reducing intracellular ROS and regulating expression of genes involved in glucose metabolism. Further research is needed to achieve a better understanding of the signaling pathway involved in the antioxidant effect of mogrosides.

  8. Eplerenone-Mediated Aldosterone Blockade Prevents Renal Fibrosis by Reducing Renal Inflammation, Interstitial Cell Proliferation and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Hui Chen

    2013-11-01

    Full Text Available Background/Aims: Prolonged elevation of serum aldosterone leads to renal fibrosis. Inflammation also plays a role in the pathogenesis of renal disease. We used a rat model of interstitial renal fibrosis to test the hypothesis that eplerenone-mediated aldosterone blockade prevents renal fibrosis due to its anti-inflammatory and anti-proliferative effects. Methods: Eplerenone (a selective aldosterone blocker or vehicle (control, was given to male Wistar rats (50 mg/kg, twice daily for 7 days before unilateral ureteral obstruction (UUO and for an additional 28 days after surgery. Body weight, blood pressure, renal histo-morphology, immune-staining for macrophages, monocyte chemotactic protein-1, proliferating cell nuclear antigen, α-smooth muscle actin, and serum and urine markers of renal function and oxidative stress were determined for both groups on 7, 14, and 28 days after surgery. Results: Epleronone had no effect on body weight or blood pressure. However, eplerenone inhibited the development of renal fibrosis, inflammation (macrophage and monocyte infiltration, interstitial cell proliferation, and activation of interstitial cells (α-SMA expression. Epleronone also reduced oxidative stress. Conclusion: The anti-fibrotic effect of eplerenone appears to be unrelated to its effect on blood pressure. Eplerenone inhibits renal inflammation, interstitial cell proliferation, phenotypic changes of interstitial cells, and reduces oxidative stress.

  9. The potential mechanism of tiliroside-dependent inhibition of t-butylhydroperoxide-induced oxidative stress in endometrial carcinoma cells.

    Science.gov (United States)

    Tomczyk, Michal; Tumanov, Aleksander; Zaniewska, Agnieszka; Surazynski, Arkadiusz

    2010-07-01

    The effects of oxidative stress on collagen and DNA biosynthesis, beta-galactosidase activity, the expression of the beta-integrin receptor, FAK, the insulin-like growth factor-I receptor (IGF-IR), the hypoxia-inducible factor-1 (HIF-1), and the mitogen-activated protein kinases (MAP/ERK(1), ERK(2)) were evaluated in human endometrial carcinoma cells. Subconfluent cells were subjected to oxidative stress with 30 microM t-butylhydroperoxide (t-BHP) for 1 h per day over the course of 5 days. It was found that oxidative stress contributed to an increase in the beta-galactosidase activity as well as to the inhibition of collagen and DNA biosynthesis. The mechanism of the process was found at the level of IGF-IR and HIF-1 alpha. An increase in the expression of HIF-1 alpha and a decrease in the expression of IGF-IR were observed in the cells subjected to oxidative stress. The role of IGF-IR signalling in the process was confirmed by an experiment showing downregulation of MAP kinases ERK(1) and ERK(2) expression in the studied cells. This phenomenon is probably responsible for the drastic inhibition of protein (up to 40 % of control) and DNA biosynthesis (up to 65 % of control) in the cells. An addition of tiliroside to the cells medium restored all parameters to the control level, including IGF-IR and HIF-1 alpha expressions. The data suggest that the antioxidative activity of tiliroside isolated from Potentilla argentea may originate at the level of IGF-IR and HIF-1 alpha signalling.

  10. Oxidative stress triggered by naturally occurring flavone apigenin results in senescence and chemotherapeutic effect in human colorectal cancer cells.

    Science.gov (United States)

    Banerjee, Kacoli; Mandal, Mahitosh

    2015-08-01

    Recent studies involving phytochemical polyphenolic compounds have suggested flavones often exert pro-oxidative effect in vitro against wide array of cancer cell lines. The aim of this study was to evaluate the in-vitro pro-oxidative activity of apigenin, a plant based flavone against colorectal cancer cell lines and investigate cumulative effect on long term exposure. In the present study, treatment of colorectal cell lines HT-29 and HCT-15 with apigenin resulted in anti-proliferative and apoptotic effects characterized by biochemical and morphological changes, including loss of mitochondrial membrane potential which aided in reversing the impaired apoptotic machinery leading to negative implications in cancer pathogenesis. Apigenin induces rapid free radical species production and the level of oxidative damage was assessed by qualitative and quantitative estimation of biochemical markers of oxidative stress. Increased level of mitochondrial superoxide suggested dose dependent mitochondrial oxidative damage which was generated by disruption in anti-apoptotic and pro-apoptotic protein balance. Continuous and persistent oxidative stress induced by apigenin at growth suppressive doses over extended treatment time period was observed to induce senescence which is a natural cellular mechanism to attenuate tumor formation. Senescence phenotype inducted by apigenin was attributed to changes in key molecules involved in p16-Rb and p53 independent p21 signaling pathways. Phosphorylation of retinoblastoma was inhibited and significant up-regulation of p21 led to simultaneous suppression of cyclins D1 and E which indicated the onset of senescence. Pro-oxidative stress induced premature senescence mediated by apigenin makes this treatment regimen a potential chemopreventive strategy and an in vitro model for aging research.

  11. Oxidative stress triggered by naturally occurring flavone apigenin results in senescence and chemotherapeutic effect in human colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Kacoli Banerjee

    2015-08-01

    Full Text Available Recent studies involving phytochemical polyphenolic compounds have suggested flavones often exert pro-oxidative effect in vitro against wide array of cancer cell lines. The aim of this study was to evaluate the in-vitro pro-oxidative activity of apigenin, a plant based flavone against colorectal cancer cell lines and investigate cumulative effect on long term exposure. In the present study, treatment of colorectal cell lines HT-29 and HCT-15 with apigenin resulted in anti-proliferative and apoptotic effects characterized by biochemical and morphological changes, including loss of mitochondrial membrane potential which aided in reversing the impaired apoptotic machinery leading to negative implications in cancer pathogenesis. Apigenin induces rapid free radical species production and the level of oxidative damage was assessed by qualitative and quantitative estimation of biochemical markers of oxidative stress. Increased level of mitochondrial superoxide suggested dose dependent mitochondrial oxidative damage which was generated by disruption in anti-apoptotic and pro-apoptotic protein balance. Continuous and persistent oxidative stress induced by apigenin at growth suppressive doses over extended treatment time period was observed to induce senescence which is a natural cellular mechanism to attenuate tumor formation. Senescence phenotype inducted by apigenin was attributed to changes in key molecules involved in p16-Rb and p53 independent p21 signaling pathways. Phosphorylation of retinoblastoma was inhibited and significant up-regulation of p21 led to simultaneous suppression of cyclins D1 and E which indicated the onset of senescence. Pro-oxidative stress induced premature senescence mediated by apigenin makes this treatment regimen a potential chemopreventive strategy and an in vitro model for aging research.

  12. Oxidative stress in neurodegenerative diseases

    Institute of Scientific and Technical Information of China (English)

    Xueping Chen; Chunyan Guo; Jiming Kong

    2012-01-01

    Reactive oxygen species are constantly produced in aerobic organisms as by-products of normal oxygen metabolism and include free radicals such as superoxide anion (O2-) and hydroxyl radical (OH-), and non-radical hydrogen peroxide (H2O2). The mitochondrial respiratory chain and enzymatic reactions by various enzymes are endogenous sources of reactive oxygen species. Exogenous reactive oxygen species -inducing stressors include ionizing radiation, ultraviolet light, and divergent oxidizing chemicals. At low concentrations, reactive oxygen species serve as an important second messenger in cell signaling; however, at higher concentrations and long-term exposure, reactive oxygen species can damage cellular macromolecules such as DNA, proteins, and lipids, which leads to necrotic and apoptotic cell death. Oxidative stress is a condition of imbalance between reactive oxygen species formation and cellular antioxidant capacity due to enhanced ROS generation and/or dysfunction of the antioxidant system. Biochemical alterations in these macromolecular components can lead to various pathological conditions and human diseases, especially neurodegenerative diseases. Neurodegenerative diseases are morphologically featured by progressive cell loss in specific vulnerable neuronal cells, often associated with cytoskeletal protein aggregates forming inclusions in neurons and/or glial cells. Deposition of abnormal aggregated proteins and disruption of metal ions homeostasis are highly associated with oxidative stress. The main aim of this review is to present as much detailed information as possible that is available on various neurodegenerative disorders and their connection with oxidative stress. A variety of therapeutic strategies designed to address these pathological processes are also described. For the future therapeutic direction, one specific pathway that involves the transcription factor nuclear factor erythroid 2-related factor 2 is receiving considerable attention.

  13. Cytoprotective effects of Morinda officinalis against hydrogen peroxide-induced oxidative stress in Leydig TM3 cells

    Institute of Scientific and Technical Information of China (English)

    Mun-Seog Chang; Won-Nam Kim; Woong-Mo Yang; Hyu-Young Kim; Ji-Hoon Oh; Seong-Kyu Park

    2008-01-01

    Aim: To investigate the antioxidant effects of Morinda officinalis (Morindae radix, MR) on H202-induced oxidative stress in cultured mouse TM3 Leydig cells. Methods: We carded out 2,2-diphenyl-l-picrylhydrazyl free radical scavenging, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lipid peroxidation, testosterone enzyme immunoassay, superoxide dismutase (SOD), and catalase (CAT) assays in Leydig TM3 cells. Results: MR showed a 47.8% 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect in TM3 cells with no significant cytotoxicity. Oxi- dative stress was induced in TM3 cells with 100 μmol H2O2, and treatment of the cells with 250 μg/mL MR showed the most significant protective effect (64%, P < 0.001) in the cell viability assay with a decreased lipid peroxidation level (1.75 nmol/mg protein, P < 0.05), increased testosterone production (43.5 pg/mL), and improvements in SOD activity (7.49 units of SOD/mg protein, P < 0.001) and CAT activity (74.6 units of CAT/mg protein, P < 0.001). Conclusion: These findings indicate that MR, as an antioxidant, protects functions of cultured mouse TM3 Leydig cells from H2O2-induced oxidative stress. (Asian J Androl 2008 Jul; 10: 667-674)

  14. Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells

    Directory of Open Access Journals (Sweden)

    Hyunyun Kim

    2016-01-01

    Full Text Available Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS causes cardiovascular diseases (CVDs, atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs, for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair.

  15. Overexpression of DNA ligase III in mitochondria protects cells against oxidative stress and improves mitochondrial DNA base excision repair.

    Science.gov (United States)

    Akbari, Mansour; Keijzers, Guido; Maynard, Scott; Scheibye-Knudsen, Morten; Desler, Claus; Hickson, Ian D; Bohr, Vilhelm A

    2014-04-01

    Base excision repair (BER) is the most prominent DNA repair pathway in human mitochondria. BER also results in a temporary generation of AP-sites, single-strand breaks and nucleotide gaps. Thus, incomplete BER can result in the generation of DNA repair intermediates that can disrupt mitochondrial DNA replication and transcription and generate mutations. We carried out BER analysis in highly purified mitochondrial extracts from human cell lines U2OS and HeLa, and mouse brain using a circular DNA substrate containing a lesion at a specific position. We found that DNA ligation is significantly slower than the preceding mitochondrial BER steps. Overexpression of DNA ligase III in mitochondria improved the rate of overall BER, increased cell survival after menadione induced oxidative stress and reduced autophagy following the inhibition of the mitochondrial electron transport chain complex I by rotenone. Our results suggest that the amount of DNA ligase III in mitochondria may be critical for cell survival following prolonged oxidative stress, and demonstrate a functional link between mitochondrial DNA damage and repair, cell survival upon oxidative stress, and removal of dysfunctional mitochondria by autophagy.

  16. Protective effect of Melissa officinalis extract against H2O2-induced oxidative stress in human vascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Leila Safaeian

    2016-01-01

    Full Text Available Melissa officinalis L. is a medicinal plant with a large variety of pharmacological effects and traditional applications. This study aimed to evaluate the protective and antioxidant activities of the extract of M. officinalis aerial parts on human umbilical vein endothelial cells (HUVECs under oxidative stress induced by H 2 O 2 . Cells were incubated with H 2 O 2 (0.5 mM, 2 h after pretreatment with M. officinalis extract (25-500 µg/mL. Cell viability was evaluated by 3-(4, 5- Dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay. The concentration of hydroperoxides and ferric reducing antioxidant power (FRAP were measured in intra- and extra-cellular fluids. Pretreatment of HUVECs with M. officinalis extract at the concentrations of 100-500 µg/mL improved the cell viability after exposure to H 2 O 2 significantly. It also decreased hydroperoxides concentration and increased FRAP value in both intra- and extra-cellular fluids. The results revealed antioxidant and cytoprotective effects of M. officinalis against H 2 O 2 -induced oxidative stress in HUVECs. Due to the valuable antioxidant activity , this plant extract may have potential benefits for the prevention of cardiovascular diseases associated with oxidative stress.

  17. Oxidative stress regulated heme-oxygenase-1 and glutathione S-transferase-m1 gene expression changes in cell lines exposed to melanins

    Institute of Scientific and Technical Information of China (English)

    Jie Li; Peng Zhao; Junfeng Yang; Renyun Zhang; Shen Li; Dan Liu

    2011-01-01

    To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson's disease, we treated neuroblastoma cells (SK-N-SH) and glioma cells with Fenton's reagent, iron chelating agent, neuromelanin and dopamine melanin. We investigated the changes in expression of nine oxidative stress-related genes and proteins. The levels of mRNAs for heme-oxygenase-1 and glutathione S-transferase-m1 were significantly reduced in SK-N-SH cells exposed to oxidative stress, and increased in glial cells treated with deferoxamine. These results revealed that SK-N-SH neurons react sensitively to oxidative stress, which implies different outcomes between these two types of cells in the substantia nigra. Moreover, the influences of neuromelanin and dopamine melanin on cell function are varied, and dopamine melanin is not a good model for neuromelanin.

  18. Residual stresses and strength of multilayer tape cast solid oxide fuel and electrolysis half-cells

    DEFF Research Database (Denmark)

    Charlas, Benoit; Frandsen, Henrik Lund; Brodersen, Karen;

    2015-01-01

    The cost-effectiveness of Solid Oxide Cells production can be improved by introducing "multilayer-tape-casting" (MTC: sequential casting of the layers) and co-sintering of the half-cells. MTC additionally results in more homogeneous layers with strong interfaces. However, the thermal expansion...

  19. Implications of altered glutathione metabolism in aspirin-induced oxidative stress and mitochondrial dysfunction in HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Haider Raza

    Full Text Available We have previously reported that acetylsalicylic acid (aspirin, ASA induces cell cycle arrest, oxidative stress and mitochondrial dysfunction in HepG2 cells. In the present study, we have further elucidated that altered glutathione (GSH-redox metabolism in HepG2 cells play a critical role in ASA-induced cytotoxicity. Using selected doses and time point for ASA toxicity, we have demonstrated that when GSH synthesis is inhibited in HepG2 cells by buthionine sulfoximine (BSO, prior to ASA treatment, cytotoxicity of the drug is augmented. On the other hand, when GSH-depleted cells were treated with N-acetyl cysteine (NAC, cytotoxicity/apoptosis caused by ASA was attenuated with a significant recovery in oxidative stress, GSH homeostasis, DNA fragmentation and some of the mitochondrial functions. NAC treatment, however, had no significant effects on the drug-induced inhibition of mitochondrial aconitase activity and ATP synthesis in GSH-depleted cells. Our results have confirmed that aspirin increases apoptosis by increased reactive oxygen species production, loss of mitochondrial membrane potential and inhibition of mitochondrial respiratory functions. These effects were further amplified when GSH-depleted cells were treated with ASA. We have also shown that some of the effects of aspirin might be associated with reduced GSH homeostasis, as treatment of cells with NAC attenuated the effects of BSO and aspirin. Our results strongly suggest that GSH dependent redox homeostasis in HepG2 cells is critical in preserving mitochondrial functions and preventing oxidative stress associated complications caused by aspirin treatment.

  20. Oxidative stress-induced cell cycle blockage and a protease-independent programmed cell death in  microaerophilic Giardia lamblia

    Directory of Open Access Journals (Sweden)

    Esha Ghosh

    2009-03-01

    Full Text Available Esha Ghosh1, Arjun Ghosh1, Amar Nath Ghosh2, Tomoyoshi Nozaki3, Sandipan Ganguly11Division of Parasitology; 2Division of Electron Microscopy, National Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata, West Bengal, India; 3Division of Parasitology, National Institute of Infectious Diseases, Tokyo, JapanAbstract: Giardia lamblia is a microaerophilic human gastrointestinal parasite and considered as an early-diverged eukaryote. In vitro oxidative stress generation plays a significant role in cell cycle progression and cell death of this parasite. In the present study hydrogen peroxide, metronidazole, and a modified growth medium without cysteine and ascorbic acid have been chosen as oxidative stress-inducing agents. Cell cycle progression has been found to be regulated by different types of oxidative stresses. Apoptosis is not an established pathway in Giardia, which is devoid of ideal mitochondria, but in the present investigation, apoptosis-like programmed cell death has been found by the experiments like AnnexinV-FITC assay, DNA fragmentation pattern, etc. On the contrary, Caspase-9 assay, which confirms the caspase-mediated apoptotic pathway, has been found to be negative in all the stress conditions. Protease inhibitor assay confirmed that, even in absence of any proteases, programmed cell death does occur in this primitive eukaryote. All these results signify a novel pathway of programmed suicidal death in Giardia lamblia under oxidative stress. This is the first demonstration of protease-independent programmed cell death regulation in Giardia exclusive for its own specialties.Keywords: Giardia lamblia, oxidative stress, reactive oxygen species, programmed cell death, apoptosis, early branching eukaryotes

  1. Tat-biliverdin reductase A protects INS-1 cells from human islet amyloid polypeptide-induced cytotoxicity by alleviating oxidative stress and ER stress.

    Science.gov (United States)

    Lee, Su Jin; Kang, Hyung Kyung; Eum, Won Sik; Park, Jinseu; Choi, Soo Young; Kwon, Hyeok Yil

    2017-02-15

    Human islet amyloid polypeptide (hIAPP), a major constituent of islet amyloid deposits, induces pancreatic β-cell apoptosis and eventually contributes to β-cell deficit in patients with type 2 diabetes mellitus (T2DM). In this study, Tat-mediated transduction of biliverdin reductase A (BLVRA) was investigated in INS-1 cells to examine whether exogenous supplementation of BLVRA prevented hIAPP-induced apoptosis and dysfunction in insulin secretion in β-cells. Tat-BLVRA fusion protein was efficiently delivered into INS-1 cells in a time- and dose-dependent manner. Exposure of cells to hIAPP induced apoptotic cell death, which was dose-dependently inhibited by pre-treatment with Tat-BLVRA for 1 h. Transduced Tat-BLVRA reduced hIAPP-evoked generation of reactive oxygen species, a crucial mediator of β-cell destruction. Immunoblot analysis showed that Tat-BLVRA suppressed hIAPP-induced increase in the levels of proteins involved in endoplasmic reticulum (ER) stress and apoptosis signaling. Transduced Tat-BLVRA also recovered hIAPP-induced dysfunction in basal and glucose-stimulated insulin secretions. These results suggested that transduced Tat-BLVRA enhanced the tolerance of β-cells against IAPP-induced cytotoxicity by alleviating oxidative stress and ER stress. Therefore, Tat-mediated transduction of BLVRA may provide a potential tool to ameliorate β-cell deficit in pancreas with T2DM.

  2. Heparan sulfate proteoglycans mediate Aβ-induced oxidative stress and hypercontractility in cultured vascular smooth muscle cells

    OpenAIRE

    2016-01-01

    Background Substantial evidence suggests that amyloid-β (Aβ) species induce oxidative stress and cerebrovascular (CV) dysfunction in Alzheimer’s disease (AD), potentially contributing to the progressive dementia of this disease. The upstream molecular pathways governing this process, however, are poorly understood. In this report, we examine the role of heparan sulfate proteoglycans (HSPG) in Aβ-induced vascular smooth muscle cell (VSMC) dysfunction in vitro. Results Our results demonstrate t...

  3. Proteases and oxidant stress control organic dust induction of inflammatory gene expression in lung epithelial cells

    OpenAIRE

    Natarajan, Kartiga; Gottipati, Koteswara R.; Berhane, Kiflu; Samten, Buka; Pendurthi, Usha; Boggaram, Vijay

    2016-01-01

    Background Persistant inflammatory responses to infectious agents and other components in organic dust underlie lung injury and development of respiratory diseases. Organic dust components responsible for eliciting inflammation and the mechanisms by which they cause lung inflammation are not fully understood. We studied the mechanisms by which protease activities in poultry dust extracts and intracellular oxidant stress induce inflammatory gene expression in A549 and Beas2B lung epithelial ce...

  4. Loss of Kitlow progenitors, reduced stem cell factor and high oxidative stress underlie gastric dysfunction in progeric mice.

    Science.gov (United States)

    Izbeki, Ferenc; Asuzu, David T; Lorincz, Andrea; Bardsley, Michael R; Popko, Laura N; Choi, Kyoung Moo; Young, David L; Hayashi, Yujiro; Linden, David R; Kuro-o, Makoto; Farrugia, Gianrico; Ordog, Tamas

    2010-08-15

    Gastrointestinal functions decline with ageing leading to impaired quality of life, and increased morbidity and mortality. Neurodegeneration is believed to underlie ageing-associated dysmotilities but the mechanisms have not been fully elucidated. We used progeric mice deficient in the anti-ageing peptide Klotho to investigate the contribution of key cell types of the gastric musculature to ageing-associated changes in stomach function and the underlying mechanisms. Klotho expression, enteric neurons, interstitial cells of Cajal (ICC), smooth muscle cells and electrical activity were assessed by immunofluorescence, confocal microscopy, 3-dimensional reconstruction, flow cytometry, quantitative RT-PCR, Western immunoblotting and intracellular recordings. Gastric emptying of solids was analysed by the [13C]octanoic acid breath test. Circulating and tissue trophic factors were measured by enzyme immunoassays and quantitative RT-PCR. The role of oxidative stress was investigated in organotypic cultures. Klotho expression was detected in gastric glands, myenteric neurons and smooth muscle cells. Progeric Klotho-deficient mice had profound loss of ICC and ICC stem cells without a significant decrease in neuron counts, expression of neuronal nitric oxide synthase or smooth muscle myosin. Slow wave amplitude and nitrergic inhibitory junction potentials were reduced while solid emptying was unchanged. Klotho-deficient mice were marantic and had low insulin, insulin-like growth factor-I and membrane-bound stem cell factor. Klotho deficiency accentuated oxidative stress and ICC loss. We conclude that Klotho-deficient, progeric mice display a gastric phenotype resembling human ageing and involving profound ICC loss. Klotho protects ICC by preserving their precursors, limiting oxidative stress, and maintaining nutritional status and normal levels of trophic factors important for ICC differentiation.

  5. Oxidative Stress in Retinal Muller Cells contributes to Dysfunction of Retinal Glutamate Uptake and Altered Protein Expression

    DEFF Research Database (Denmark)

    Toft-Kehler, Anne Katrine; Skytt, Dorte Marie; Kolko, Miriam

    2015-01-01

    Purpose: The viability of retinal ganglion cells (RGC) is essential to maintain the neuronal function of the retina. Müller cells (MC) are assumed to be vital in neuroprotection of the RGC. In this study, we evaluate the ability of oxidative stressed and energy restricted MC to remove glutamate f...... from the extracellular space and evaluate related changes in gene and protein expressions. Methods: The human Müller glial cell line, MIO-M1, kindly provided by Astrid Limb, was used in all experiments. Changes in glutamate uptake were evaluated by kinetic uptake studies using 3H...

  6. Functional adaptation to oxidative stress by memory T cells: an analysis of the role in the cardiovascular disease process.

    Science.gov (United States)

    Elahi, Maqsood M; Matata, Bashir M

    2008-11-21

    T cells participate in combating infection and critically determine the outcomes in any given disease process. Impaired immune response occurs in a number disease processes such as in cancer and atherosclerosis although the underlying mechanisms are still not fully understood. This article gives an up-to-date review of T cells development and functional adaptation to pathophysiological stimuli and participation in the cardiovascular disease process. In addition, we have discussed the signaling pathways controlled by the microenvironment that determine T cells function and resultant type of immune response. We have also discussed in detail how oxidative stress is a key component of the micro environmental interaction.

  7. Piper sarmentosum increases nitric oxide production in oxidative stress: a study on human umbilical vein endothelial cells

    Directory of Open Access Journals (Sweden)

    Azizah Ugusman

    2010-01-01

    Full Text Available OBJECTIVE: Nitric oxide produced by endothelial nitric oxide synthase (eNOS possesses multiple anti-atherosclerotic properties. Hence, enhanced expression of eNOS and increased Nitric oxide levels may protect against the development of atherosclerosis. Piper sarmentosum is a tropical plant with antioxidant and anti-inflammatory activities. This study aimed to investigate the effects of Piper sarmentosum on the eNOS and Nitric oxide pathway in cultured human umbilical vein endothelial cells (HUVECs. METHODS: HUVECs were divided into four groups: control, treatment with 180 μM hydrogen peroxide (H2O2, treatment with 150 μg/mL aqueous extract of Piper sarmentosum, and concomitant treatment with aqueous extract of PS and H2O2 for 24 hours. Subsequently, HUVECs were harvested and eNOS mRNA expression was determined using qPCR. The eNOS protein level was measured using ELISA, and the eNOS activity and Nitric oxide level were determined by the Griess reaction. RESULTS: Human umbilical vein endothelial cells treated with aqueous extract of Piper sarmentosum showed a marked induction of Nitric oxide. Treatment with PS also resulted in increased eNOS mRNA expression, eNOS protein level and eNOS activity in HUVECs. CONCLUSION: Aqueous extract of Piper sarmentosum may improve endothelial function by promoting NO production in HUVECs.

  8. Quercetin protects human peripheral blood mononuclear cells from OTA-induced oxidative stress, genotoxicity, and inflammation.

    Science.gov (United States)

    Periasamy, Ramyaa; Kalal, Iravathy Goud; Krishnaswamy, Rajashree; Viswanadha, VijayaPadma

    2016-07-01

    Ochratoxin A (OTA) is one of the most abundant food-contaminating mycotoxins world wide, and is detrimental to human and animal health. This study evaluated the protective effect of quercetin against OTA-induced cytotoxicity, genotoxicity, and inflammatory response in lymphocytes. Cytotoxicity determined by MTT assay revealed IC20 value of OTA to be 20 µM, which was restored to near control values by pretreatment with quercetin. Oxidative stress parameters such as antioxidant enzymes, LPO and PCC levels indicated that quercetin exerted a protective effect on OTA-induced oxidative stress. Quercetin exerted an antigenotoxic effect on OTA-induced genotoxicity, by significantly reducing the number of structural aberrations in chromosomes and comet parameters like, % olive tail moment from 2.76 ± 0.02 to 0.56 ± 0.02 and % tail DNA from 56.23 ± 2.56 to 12.36 ± 0.56 as determined by comet assay. OTA-induced NO, TNF-α, IL-6, and IL-8 were significantly reduced in the quercetin pretreated samples indicating its anti-inflammatory role. Our results demonstrate for the first time that quercetin exerts a cytoprotective effect against OTA-induced oxidative stress, genotoxicity, and inflammation in lymphocytes. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 855-865, 2016.

  9. Studying the cytotoxicity and oxidative stress induced by two kinds of bentonite particles on human B lymphoblast cells in vitro.

    Science.gov (United States)

    Zhang, Meibian; Lu, Yezhen; Li, Xiaoxue; Chen, Qing; Lu, Longxi; Xing, Mingluan; Zou, Hua; He, Jiliang

    2010-02-12

    The aim of the present study was to evaluate the cytotoxicity and oxidative stress induced by native and active bentonite particles (BPs) on human B lymphoblast cells using seven assays. Our results showed that the order of cytotoxicity was: active BPs>native BPs>quartz particles (DQ-12)>gypsum, according to the IC50 values in CCK-8 assay and neutral red uptake (NRU) assay. The lactate dehydrogenase (LDH) leakage, the proportions of early apoptotic cells, the reactive oxygen species (ROS) generation, the superoxide dismutase (SOD) inhibition and the malondialdehyde (MDA) release in the native and active BPs groups were significantly higher than those in the gypsum and DQ-12 groups (Pstress induced by active BPs was significantly higher than that induced by native BPs (Pstress on human B lymphoblast cells in vitro. The cytotoxic difference between active BPs and native BPs may be associated with the adsorption capacity of BPs and oxidative stress induced by BPs to a certain extent. The insoluble particle fractions may play a main role in the cytotoxic effects and oxidative stress induced by BPs.

  10. Neuroglobin in Breast Cancer Cells: Effect of Hypoxia and Oxidative Stress on Protein Level, Localization, and Anti-Apoptotic Function

    Science.gov (United States)

    Fiocchetti, Marco; Cipolletti, Manuela; Leone, Stefano; Naldini, Antonella; Carraro, Fabio; Giordano, Daniela; Verde, Cinzia; Ascenzi, Paolo; Marino, Maria

    2016-01-01

    The over-expression of human neuroglobin (NGB), a heme-protein preferentially expressed in the brain, displays anti-apoptotic effects against hypoxic/ischemic and oxidative stresses enhancing neuron survival. As hypoxic and oxidative stress injury frequently occurs in fast proliferating neoplastic tissues, here, the effect of these stressors on the level, localization, and anti-apoptotic function of NGB in wild type and NGB-stable-silenced MCF-7 breast cancer cells has been assessed. The well-known endogenous NGB inducer 17β-estradiol (E2) has been used as positive control. The median pO2 present in tumor microenvironment of breast cancer patients (i.e., 2% O2) does not affect the NGB level in breast cancer cells, whereas hydrogen peroxide and lead(IV) acetate, which increase intracellular reactive oxygen species (ROS) level, enhance the NGB levels outside the mitochondria and still activate apoptosis. However, E2-induced NGB up-regulation in mitochondria completely reverse lead(IV) acetate-induced PARP cleavage. These results indicate that the NGB level could represent a marker of oxidative-stress in MCF-7 breast cancer cells; however, the NGB ability to respond to injuring stimuli by preventing apoptosis requires its re-allocation into the mitochondria. As a whole, present data might lead to a new direction in understanding NGB function in cancer opening new avenues for the therapeutic intervention. PMID:27149623

  11. Linoleic acid suppresses colorectal cancer cell growth by inducing oxidant stress and mitochondrial dysfunction

    Directory of Open Access Journals (Sweden)

    Shen Shengrong

    2010-09-01

    Full Text Available Abstract Some polyunsaturated fatty acids (PUFAs, if not all, have been shown to have tumoricidal action, but their exact mechanism(s of action is not clear. In the present study, we observed that n-6 PUFA linoleic acid (LA inhibited tumor cell growth at high concentrations (above 300 μM; while low concentrations (100-200 μM promoted proliferation. Analysis of cell mitochondrial membrane potential, reactive oxygen species (ROS formation, malondialdehyde (MDA accumulation and superoxide dismutase (SOD activity suggested that anti-cancer action of LA is due to enhanced ROS generation and decreased cell anti-oxidant capacity that resulted in mitochondrial damage. Of the three cell lines tested, semi-differentiated colorectal cancer cells RKO were most sensitive to the cytotoxic action of LA, followed by undifferentiated colorectal cancer cell line (LOVO while the normal human umbilical vein endothelial cells (HUVEC were the most resistant (the degree of sensitivity to LA is as follows: RKO > LOVO > HUVEC. LA induced cell death was primed by mitochondrial apoptotic pathway. Pre-incubation of cancer cells with 100 μM LA for 24 hr enhanced sensitivity of differentiated and semi-differentiated cells to the subsequent exposure to LA. The relative resistance of LOVO cells to the cytotoxic action of LA is due to a reduction in the activation of caspase-3. Thus, LA induced cancer cell apoptosis by enhancing cellular oxidant status and inducing mitochondrial dysfunction.

  12. Thioredoxin reductase deficiency potentiates oxidative stress, mitochondrial dysfunction and cell death in dopaminergic cells.

    Directory of Open Access Journals (Sweden)

    Pamela Lopert

    Full Text Available Mitochondria are considered major generators of cellular reactive oxygen species (ROS which are implicated in the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD. We have recently shown that isolated mitochondria consume hydrogen peroxide (H₂O₂ in a substrate- and respiration-dependent manner predominantly via the thioredoxin/peroxiredoxin (Trx/Prx system. The goal of this study was to determine the role of Trx/Prx system in dopaminergic cell death. We asked if pharmacological and lentiviral inhibition of the Trx/Prx system sensitized dopaminergic cells to mitochondrial dysfunction, increased steady-state H₂O₂ levels and death in response to toxicants implicated in PD. Incubation of N27 dopaminergic cells or primary rat mesencephalic cultures with the Trx reductase (TrxR inhibitor auranofin in the presence of sub-toxic concentrations of parkinsonian toxicants paraquat; PQ or 6-hydroxydopamine; 6OHDA (for N27 cells resulted in a synergistic increase in H₂O₂ levels and subsequent cell death. shRNA targeting the mitochondrial thioredoxin reductase (TrxR2 in N27 cells confirmed the effects of pharmacological inhibition. A synergistic decrease in maximal and reserve respiratory capacity was observed in auranofin treated cells and TrxR2 deficient cells following incubation with PQ or 6OHDA. Additionally, TrxR2 deficient cells showed decreased basal mitochondrial oxygen consumption rates. These data demonstrate that inhibition of the mitochondrial Trx/Prx system sensitizes dopaminergic cells to mitochondrial dysfunction, increased steady-state H₂O₂, and cell death. Therefore, in addition to their role in the production of cellular H₂O₂ the mitochondrial Trx/Prx system serve as a major sink for cellular H₂O₂ and its disruption may contribute to dopaminergic pathology associated with PD.

  13. The Possible Role of Nitric Oxide and Oxidative Stress in the Enhanced Apoptosis of Cardiac Cells in Cirrhotic Rats

    Directory of Open Access Journals (Sweden)

    Hamed Shafaroodi

    2017-02-01

    Full Text Available  Cirrhosis has been related with hyperdynamic circulation, manifesting as increased cardiac output and decreased systemic vascular resistance. In the present study we examined the cirrhosis outcome on apoptosis of rat hearts. We also tried to explore the role of nitric oxide (NO and oxidative stress in the probable changed apoptosis of cirrhotic hearts. Twenty eight days after ligation of bile duct, heart tissues were tested for apoptosis. The extent of malondialdehyde (MDA, and the activities of catalase (CAT, glutathione peroxidase (GSHPx and superoxide dismutase (SOD have been calculated in heart tissues. The cirrhotic hearts exhibited structural defects and greater apoptosis. Chronic treatment of cirrhotic rats with L-NAME, a non-selective inhibitor of NO synthase, inhibited heart structural defects and reduced apoptosis of hearts. We also showed that cirrhotic rat hearts had an enhanced level of MDA and reduced activities of CAT, GSHPx and SOD. When the animals were treated by L-NAME chronically, the MDA level reduced and activities of CAT, GSHPx and SOD augmented in cirrhotic heart. In conclusion, increased apoptosis of cirrhotic hearts probably happen due to NO overproduction and increased oxidative stress in hearts of cirrhotic rats.

  14. Hydrostatic pressure and shear stress affect endothelin-1 and nitric oxide release by endothelial cells in bioreactors.

    Science.gov (United States)

    Vozzi, Federico; Bianchi, Francesca; Ahluwalia, Arti; Domenici, Claudio

    2014-01-01

    Abundant experimental evidence demonstrates that endothelial cells are sensitive to flow; however, the effect of fluid pressure or pressure gradients that are used to drive viscous flow is not well understood. There are two principal physical forces exerted on the blood vessel wall by the passage of intra-luminal blood: pressure and shear. To analyze the effects of pressure and shear independently, these two stresses were applied to cultured cells in two different types of bioreactors: a pressure-controlled bioreactor and a laminar flow bioreactor, in which controlled levels of pressure or shear stress, respectively, can be generated. Using these bioreactor systems, endothelin-1 (ET-1) and nitric oxide (NO) release from human umbilical vein endothelial cells were measured under various shear stress and pressure conditions. Compared to the controls, a decrease of ET-1 production by the cells cultured in both bioreactors was observed, whereas NO synthesis was up-regulated in cells under shear stress, but was not modulated by hydrostatic pressure. These results show that the two hemodynamic forces acting on blood vessels affect endothelial cell function in different ways, and that both should be considered when planning in vitro experiments in the presence of flow. Understanding the individual and synergic effects of the two forces could provide important insights into physiological and pathological processes involved in vascular remodeling and adaptation.

  15. Inhibition of HSP90 Promotes Neural Stem Cell Survival from Oxidative Stress through Attenuating NF-κB/p65 Activation

    Directory of Open Access Journals (Sweden)

    Qian Liu

    2016-01-01

    Full Text Available Stem cell survival after transplantation determines the efficiency of stem cell treatment, which develops as a novel potential therapy for several central nervous system (CNS diseases in recent decades. The engrafted stem cells face the damage of oxidative stress, inflammation, and immune response at the lesion point in host. Among the damaging pathologies, oxidative stress directs stem cells to apoptosis and even death through several signalling pathways and DNA damage. However, the in-detail mechanism of stem cell survival from oxidative stress has not been revealed clearly. Here, in this study, we used hydrogen peroxide (H2O2 to induce the oxidative damage on neural stem cells (NSCs. The damage was in consequence demonstrated involving the activation of heat shock protein 90 (HSP90 and NF-κB/p65 signalling pathways. Further application of the pharmacological inhibitors, respectively, targeting at each signalling indicated an upper-stream role of HSP90 upon NF-κB/p65 on NSCs survival. Preinhibition of HSP90 with the specific inhibitor displayed a significant protection on NSCs against oxidative stress. In conclusion, inhibition of HSP90 would attenuate NF-κB/p65 activation by oxidative induction and promote NSCs survival from oxidative damage. The HSP90/NF-κB mechanism provides a new evidence on rescuing NSCs from oxidative stress and also promotes the stem cell application on CNS pathologies.

  16. Inhibition of HSP90 Promotes Neural Stem Cell Survival from Oxidative Stress through Attenuating NF-κB/p65 Activation

    Science.gov (United States)

    Jiang, Wenkai; Zhou, Lin

    2016-01-01

    Stem cell survival after transplantation determines the efficiency of stem cell treatment, which develops as a novel potential therapy for several central nervous system (CNS) diseases in recent decades. The engrafted stem cells face the damage of oxidative stress, inflammation, and immune response at the lesion point in host. Among the damaging pathologies, oxidative stress directs stem cells to apoptosis and even death through several signalling pathways and DNA damage. However, the in-detail mechanism of stem cell survival from oxidative stress has not been revealed clearly. Here, in this study, we used hydrogen peroxide (H2O2) to induce the oxidative damage on neural stem cells (NSCs). The damage was in consequence demonstrated involving the activation of heat shock protein 90 (HSP90) and NF-κB/p65 signalling pathways. Further application of the pharmacological inhibitors, respectively, targeting at each signalling indicated an upper-stream role of HSP90 upon NF-κB/p65 on NSCs survival. Preinhibition of HSP90 with the specific inhibitor displayed a significant protection on NSCs against oxidative stress. In conclusion, inhibition of HSP90 would attenuate NF-κB/p65 activation by oxidative induction and promote NSCs survival from oxidative damage. The HSP90/NF-κB mechanism provides a new evidence on rescuing NSCs from oxidative stress and also promotes the stem cell application on CNS pathologies.

  17. Response of Salmonella Typhi to bile-generated oxidative stress: implication of quorum sensing and persister cell populations.

    Science.gov (United States)

    Walawalkar, Yogesh D; Vaidya, Yatindra; Nayak, Vijayashree

    2016-11-01

    Salmonella Typhi can chronically persist within the gallbladder of patients suffering from gallbladder diseases. This study, intended to improve our understanding of bacterial mechanisms underlying bile adaptation, revealed that bile, which is a bactericidal agent, led to the generation of reactive oxygen species in S Typhi. Salmonella Typhi in response showed a significant increase in the production of anti-oxidative enzymes, namely superoxide dismutase and catalase. The work reports that the quorum-sensing (QS) system of S Typhi regulates the level of these enzymes during oxidative stress. In support of these observations, the quorum-sensing mutant of S Typhi was found to be sensitive to bile with significantly lower levels of anti-oxidant enzymes compared to other clinical isolates. Furthermore the addition of exogenous cell-free extracts (CFEs) of S Typhi containing the quorum-sensing signalling molecule significantly increased the levels of these enzymes within the mutant. Interestingly the CFE addition did not significantly restore the biofilm-forming ability of the mutant strain when compared with the wild-type. In the presence of ciprofloxacin and ampicillin, S Typhi formed persister cells which increased >3-fold in the presence of bile. Thus the QS-system of S Typhi aids in oxidative stress management, and enhanced persister cell populations could assist chronic bacterial persistence within the gallbladder.

  18. Involvement of PPARgamma in oxidative stress-mediated prostaglandin E(2) production in SZ95 human sebaceous gland cells.

    Science.gov (United States)

    Zhang, Qiwei; Seltmann, Holger; Zouboulis, Christos C; Konger, Raymond L

    2006-01-01

    Peroxisome proliferator-activated receptor gamma (PPARgamma) is thought to play a role in sebaceous gland cell function. We previously demonstrated in human epidermoid carcinoma KB cells that UVB irradiation activates PPARgamma via the generation of multiple oxidized glycerophosphocholine species with PPARgamma ligand activity. UVB-induced cyclooxygenase 2 (COX-2) expression was also shown to be PPARgamma-dependent. We therefore reasoned that PPARgamma activation and PPARgamma-dependent COX-2 expression may occur as a general consequence of oxidative stress. The present studies were designed to examine the effects of the oxidant tert-butylhydroperoxide (TBH) on PPARgamma activation and COX-2 expression in SZ95 sebocytes. We first verified that functional PPARgamma is expressed and activated by UVB irradiation in these cells. We next demonstrated that TBH increased PPARgamma reporter activity in SZ95 sebocytes. Increased COX-2 protein, mRNA expression, and prostaglandin E(2) (PGE(2)) production was observed after TBH or PPARgamma agonist treatment. The ability of PPARgamma agonists and TBH to induce COX-2 expression and PGE(2) production was blocked by pretreatment with the specific PPARgamma antagonist GW9662. Finally, TBH and PPARgamma agonists failed to elicit a PGE(2) response in SZ95 sebocytes stably expressing a dominant-negative PPARgamma. This study illustrates the importance of the PPARgamma system in regulating cellular responses to oxidative stress.

  19. Hemoglobin oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Croci, S.; Ortalli, I.; Pedrazzi, G. [University of Parma, Istituto di Scienze Fisiche, INFM-Udr Parma (Italy); Passeri, G. [University of Parma, Dipartimento di Medicina Interna e Scienze Biomediche (Italy); Piccolo, P. [University of Parma, Istituto di Clinica chirurgica Generale, Toracica e Vascolare (Italy)

    2000-07-15

    Venous blood obtained from healthy donors and from patients suffering from breast cancer have been treated with acetylphenylhydrazine (APH) for different time. Moessbauer spectra of the packed red cells have been recorded and compared. The largest difference occurs after 50 min of treatment with APH where the patient samples show a broad spectral pattern indicating an advanced hemoglobin oxidation. These results may have some relevance in early cancer diagnosis.

  20. Increased oxidative stress and toxicity in ADH and CYP2E1 overexpressing human hepatoma VL-17A cells exposed to high glucose.

    Science.gov (United States)

    Chandrasekaran, Karthikeyan; Swaminathan, Kavitha; Kumar, S Mathan; Clemens, Dahn L; Dey, Aparajita

    2012-05-01

    High glucose mediated oxidative stress and cell death is a well documented phenomenon. Using VL-17A cells which are HepG2 cells over-expressing alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1) and control HepG2 cells, the association of ADH and CYP2E1 with high glucose mediated oxidative stress and toxicity in liver cells was investigated. Cell viability was measured and apoptosis or necrosis was determined through caspase-3 activity, Annexin V-propidium iodide staining and detecting decreases in mitochondrial membrane potential. Reactive oxygen species, lipid peroxidation and the formation of advanced glycated-end products were assessed. The levels of several antioxidants which included glutathione, glutathione peroxidase, catalase and superoxide dismutase were altered in high glucose treated VL-17A cells. Greater toxicity was observed in VL-17A cells exposed to high glucose when compared to HepG2 cells. Oxidative stress parameters were greatly increased in high glucose exposed VL-17A cells and apoptotic cell death was observed. Inhibition of CYP2E1 or caspase 3 or addition of the antioxidant trolox led to significant decreases in high glucose mediated oxidative stress and toxicity. Thus, the over-expression of ADH and CYP2E1 in liver cells is associated with increased high glucose mediated oxidative stress and toxicity.

  1. Synthesis of novel curcuminoids accommodating a central β-enaminone motif and their impact on cell growth and oxidative stress.

    Science.gov (United States)

    De Vreese, Rob; Grootaert, Charlotte; D'hoore, Sander; Theppawong, Atiruj; Van Damme, Sam; Van Bogaert, Maarten; Van Camp, John; D'hooghe, Matthias

    2016-11-10

    Curcuminoids are high-potential drugs targeting multiple components of vital signaling pathways without being toxic, and are therefore considered to be valuable lead structures in medicinal chemistry. Unfortunately, most curcuminoids poorly reach their site of action because of low bioavailability issues, (partly) associated with the labile β-diketo structure. In that respect, curcumin derivatives bearing a central β-enaminone fragment may have improved solubility and intestinal stability, and therefore may represent a new class of analogs with higher bioactivity. In that mindset, thirteen N-alkyl enaminones were efficiently synthesized via a novel approach, using montmorillonite K10 clay and microwave irradiation. These compounds were then characterized in terms of solubility and chemical anti-oxidant properties, and were applied in screening assays for cell toxicity, growth and oxidative stress using CHO-K1, EA.hy926, HT-29 and Caco-2 cell lines. Compared to native curcumin, many nitrogen derivatives showed a stronger antiproliferative effect, which was highly structure and cell type dependent. In addition, the correlation between cell viability and reactive oxygen species production was limited. Therefore, this set of novel curcumin derivatives may be useful to unravel other mechanisms of oxidative stress-related diseases, and eventually be used as more bioavailable and bioactive alternatives for native curcumin.

  2. Pummelo Protects Doxorubicin-Induced Cardiac Cell Death by Reducing Oxidative Stress, Modifying Glutathione Transferase Expression, and Preventing Cellular Senescence

    Directory of Open Access Journals (Sweden)

    L. Chularojmontri

    2013-01-01

    Full Text Available Citrus flavonoids have been shown to reduce cardiovascular disease (CVD risks prominently due to their antioxidant effects. Here we investigated the protective effect of pummelo (Citrus maxima, CM fruit juice in rat cardiac H9c2 cells against doxorubicin (DOX- induced cytotoxicity. Four antioxidant compositions (ascorbic acid, hesperidin, naringin, and gallic acid were determined by HPLC. CM significantly increased cardiac cell survival from DOX toxicity as evaluated by MTT assay. Reduction of cellular oxidative stress was monitored by the formation of DCF fluorescent product and total glutathione (GSH levels. The changes in glutathione-S-transferase (GST activity and expression were determined by enzyme activity assay and Western blot analysis, respectively. Influence of CM on senescence-associated β-galactosidase activity (SA-β-gal was also determined. The mechanisms of cytoprotection involved reduction of intracellular oxidative stress, maintaining GSH availability, and enhanced GST enzyme activity and expression. DOX-induced cellular senescence was also attenuated by long-term CM treatment. Thus, CM fruit juice can be promoted as functional fruit to protect cells from oxidative cell death, enhance the phase II GSTP enzyme activity, and decrease senescence phenotype population induced by cardiotoxic agent such as DOX.

  3. Flavonoid Fraction of Orange and Bergamot Juices Protect Human Lung Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Stress.

    Science.gov (United States)

    Ferlazzo, Nadia; Visalli, Giuseppa; Smeriglio, Antonella; Cirmi, Santa; Lombardo, Giovanni Enrico; Campiglia, Pietro; Di Pietro, Angela; Navarra, Michele

    2015-01-01

    It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of both extracts in cell-free experimental models and then we assayed their capability to prevent the cytotoxic effects induced by H2O2. Our results demonstrated that both Citrus juice extracts reduce the generation of reactive oxygen species and membrane lipid peroxidation, improve mitochondrial functionality, and prevent DNA-oxidative damage in A549 cells incubated with H2O2. Our data indicate that the mix of flavonoids present in both bergamot and orange juices may be of use in preventing oxidative cell injury and pave the way for further research into a novel healthy approach to avoid lung disorders.

  4. Flavonoid Fraction of Orange and Bergamot Juices Protect Human Lung Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Nadia Ferlazzo

    2015-01-01

    Full Text Available It has been reported that oxidant/antioxidant imbalance triggers cell damage that in turn causes a number of lung diseases. Flavonoids are known for their health benefits, and Citrus fruits juices are one of the main food sources of these secondary plant metabolites. The present study was designed to evaluate the effect of the flavonoid fraction of bergamot and orange juices, on H2O2-induced oxidative stress in human lung epithelial A549 cells. First we tested the antioxidant properties of both extracts in cell-free experimental models and then we assayed their capability to prevent the cytotoxic effects induced by H2O2. Our results demonstrated that both Citrus juice extracts reduce the generation of reactive oxygen species and membrane lipid peroxidation, improve mitochondrial functionality, and prevent DNA-oxidative damage in A549 cells incubated with H2O2. Our data indicate that the mix of flavonoids present in both bergamot and orange juices may be of use in preventing oxidative cell injury and pave the way for further research into a novel healthy approach to avoid lung disorders.

  5. High susceptibility of activated lymphocytes to oxidative stress-induced cell death

    Directory of Open Access Journals (Sweden)

    Giovanna R. Degasperi

    2008-03-01

    Full Text Available The present study provides evidence that activated spleen lymphocytes from Walker 256 tumor bearing rats are more susceptible than controls to tert-butyl hydroperoxide (t-BOOH-induced necrotic cell death in vitro. The iron chelator and antioxidant deferoxamine, the intracellular Ca2+ chelator BAPTA, the L-type Ca2+ channel antagonist nifedipine or the mitochondrial permeability transition inhibitor cyclosporin A, but not the calcineurin inhibitor FK-506, render control and activated lymphocytes equally resistant to the toxic effects of t-BOOH. Incubation of activated lymphocytes in the presence of t-BOOH resulted in a cyclosporin A-sensitive decrease in mitochondrial membrane potential. These results indicate that the higher cytosolic Ca2+ level in activated lymphocytes increases their susceptibility to oxidative stress-induced cell death in a mechanism involving the participation of mitochondrial permeability transition.O presente estudo demonstra que linfócitos ativados de baço de ratos portadores do tumor de Walker 256 são mais susceptíveis à morte celular necrótica induzida por tert-butil hidroperóxido (t-BOOH in vitro quando comparados aos controles. O quelante de ferro e antioxidante deferoxamina, o quelante intracelular de Ca2+ BAPTA, o antagonista de canal de Ca2+ nifedipina ou o inibidor da transição de permeabilidade mitocondrial ciclosporina-A, mas não o inibidor de calcineurina FK-506, inibiram de maneira similar a morte celular induzida por t-BOOH em linfócitos ativados e controles. Os linfócitos ativados apresentaram redução do potencial de membrana mitocondrial induzida por t-BOOH num mecanismo sensível a ciclosporina-A. Nossos resultados indicam que o aumento da concentração de Ca2+ citosólico em linfócitos ativados aumenta a susceptibilidade dos mesmos à morte celular induzida por estresse oxidativo, num mecanismo envolvendo a participação do poro de transição de permeabilidade mitocondrial.

  6. Antioxidant effect of mogrosides against oxidative stress induced by palmitic acid in mouse insulinoma NIT-1 cells

    Directory of Open Access Journals (Sweden)

    Q. Xu

    2013-11-01

    Full Text Available Excessive oxidative stress in pancreatic β cells, caused by glucose and fatty acids, is associated with the pathogenesis of type 2 diabetes. Mogrosides have shown antioxidant and antidiabetic activities in animal models of diabetes, but the underlying mechanisms remain unclear. This study evaluated the antioxidant effect of mogrosides on insulinoma cells under oxidative stress caused by palmitic acid, and investigated the underlying molecular mechanisms. Mouse insulinoma NIT-1 cells were cultured in medium containing 0.75 mM palmitic acid, mimicking oxidative stress. The effects of 1 mM mogrosides were determined with the dichlorodihydrofluorescein diacetate assay for intracellular reactive oxygen species (ROS and FITC-Annexin V/PI assay for cell apoptosis. Expression of glucose transporter-2 (GLUT2 and pyruvate kinase was determined by semi-quantitative reverse-transcription polymerase chain reaction. Palmitic acid significantly increased intracellular ROS concentration 2-fold (P<0.05, and decreased expression of GLUT2 (by 60%, P<0.05 and pyruvate kinase (by 80%, P<0.05 mRNAs in NIT-1 cells. Compared with palmitic acid, co-treatment with 1 mM mogrosides for 48 h significantly reduced intracellular ROS concentration and restored mRNA expression levels of GLUT2 and pyruvate kinase. However, mogrosides did not reverse palmitic acid-induced apoptosis in NIT-1 cells. Our results indicate that mogrosides might exert their antioxidant effect by reducing intracellular ROS and regulating expression of genes involved in glucose metabolism. Further research is needed to achieve a better understanding of the signaling pathway involved in the antioxidant effect of mogrosides.

  7. Antioxidant effect of mogrosides against oxidative stress induced by palmitic acid in mouse insulinoma NIT-1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Q.; Chen, S.Y.; Deng, L.D.; Feng, L.P.; Huang, L.Z.; Yu, R.R. [Department of Pharmacy, Guilin Medical University, Guilin (China)

    2013-11-18

    Excessive oxidative stress in pancreatic β cells, caused by glucose and fatty acids, is associated with the pathogenesis of type 2 diabetes. Mogrosides have shown antioxidant and antidiabetic activities in animal models of diabetes, but the underlying mechanisms remain unclear. This study evaluated the antioxidant effect of mogrosides on insulinoma cells under oxidative stress caused by palmitic acid, and investigated the underlying molecular mechanisms. Mouse insulinoma NIT-1 cells were cultured in medium containing 0.75 mM palmitic acid, mimicking oxidative stress. The effects of 1 mM mogrosides were determined with the dichlorodihydrofluorescein diacetate assay for intracellular reactive oxygen species (ROS) and FITC-Annexin V/PI assay for cell apoptosis. Expression of glucose transporter-2 (GLUT2) and pyruvate kinase was determined by semi-quantitative reverse-transcription polymerase chain reaction. Palmitic acid significantly increased intracellular ROS concentration 2-fold (P<0.05), and decreased expression of GLUT2 (by 60%, P<0.05) and pyruvate kinase (by 80%, P<0.05) mRNAs in NIT-1 cells. Compared with palmitic acid, co-treatment with 1 mM mogrosides for 48 h significantly reduced intracellular ROS concentration and restored mRNA expression levels of GLUT2 and pyruvate kinase. However, mogrosides did not reverse palmitic acid-induced apoptosis in NIT-1 cells. Our results indicate that mogrosides might exert their antioxidant effect by reducing intracellular ROS and regulating expression of genes involved in glucose metabolism. Further research is needed to achieve a better understanding of the signaling pathway involved in the antioxidant effect of mogrosides.

  8. Adipose-Derived Mesenchymal Stem Cell Protects Kidneys against Ischemia-Reperfusion Injury through Suppressing Oxidative Stress and Inflammatory Reaction

    Directory of Open Access Journals (Sweden)

    Chua Sarah

    2011-05-01

    Full Text Available Abstract Background Reactive oxygen species are important mediators exerting toxic effects on various organs during ischemia-reperfusion (IR injury. We hypothesized that adipose-derived mesenchymal stem cells (ADMSCs protect the kidney against oxidative stress and inflammatory stimuli in rat during renal IR injury. Methods Adult male Sprague-Dawley (SD rats (n = 24 were equally randomized into group 1 (sham control, group 2 (IR plus culture medium only, and group 3 (IR plus immediate intra-renal administration of 1.0 × 106 autologous ADMSCs, followed by intravenous ADMSCs at 6 h and 24 h after IR. The duration of ischemia was 1 h, followed by 72 hours of reperfusion before the animals were sacrificed. Results Serum creatinine and blood urea nitrogen levels and the degree of histological abnormalities were markedly lower in group 3 than in group 2 (all p Conclusion ADMSC therapy minimized kidney damage after IR injury through suppressing oxidative stress and inflammatory response.

  9. Coexpressed Catalase Protects Chimeric Antigen Receptor-Redirected T Cells as well as Bystander Cells from Oxidative Stress-Induced Loss of Antitumor Activity.

    Science.gov (United States)

    Ligtenberg, Maarten A; Mougiakakos, Dimitrios; Mukhopadhyay, Madhura; Witt, Kristina; Lladser, Alvaro; Chmielewski, Markus; Riet, Tobias; Abken, Hinrich; Kiessling, Rolf

    2016-01-15

    Treatment of cancer patients by adoptive T cell therapy has yielded promising results. In solid tumors, however, T cells encounter a hostile environment, in particular with increased inflammatory activity as a hallmark of the tumor milieu that goes along with abundant reactive oxygen species (ROS) that substantially impair antitumor activity. We present a strategy to render antitumor T cells more resilient toward ROS by coexpressing catalase along with a tumor specific chimeric Ag receptor (CAR) to increase their antioxidative capacity by metabolizing H2O2. In fact, T cells engineered with a bicistronic vector that concurrently expresses catalase, along with the CAR coexpressing catalase (CAR-CAT), performed superior over CAR T cells as they showed increased levels of intracellular catalase and had a reduced oxidative state with less ROS accumulation in both the basal state and upon activation while maintaining their antitumor activity despite high H2O2 levels. Moreover, CAR-CAT T cells exerted a substantial bystander protection of nontransfected immune effector cells as measured by CD3ζ chain expression in bystander T cells even in the presence of high H2O2 concentrations. Bystander NK cells, otherwise ROS sensitive, efficiently eliminate their K562 target cells under H2O2-induced oxidative stress when admixed with CAR-CAT T cells. This approach represents a novel means for protecting tumor-infiltrating cells from tumor-associated oxidative stress-mediated repression.

  10. Differential concentration-specific effects of caffeine on cell viability, oxidative stress, and cell cycle in pulmonary oxygen toxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Kirti Kumar; Chu, Chun; Couroucli, Xanthi; Moorthy, Bhagavatula; Lingappan, Krithika, E-mail: lingappa@bcm.edu

    2014-08-08

    Highlights: • Caffeine at 0.05 mM decreases oxidative stress in hyperoxia. • Caffeine at 1 mM decreases cell viability, increases oxidative stress in hyperoxia. • Caffeine at 1 but not 0.05 mM, abrogates hyperoxia-induced G2/M arrest. - Abstract: Caffeine is used to prevent bronchopulmonary dysplasia (BPD) in premature neonates. Hyperoxia contributes to the development of BPD, inhibits cell proliferation and decreases cell survival. The mechanisms responsible for the protective effect of caffeine in pulmonary oxygen toxicity remain largely unknown. A549 and MLE 12 pulmonary epithelial cells were exposed to hyperoxia or maintained in room air, in the presence of different concentrations (0, 0.05, 0.1 and 1 mM) of caffeine. Caffeine had a differential concentration-specific effect on cell cycle progression, oxidative stress and viability, with 1 mM concentration being deleterious and 0.05 mM being protective. Reactive oxygen species (ROS) generation during hyperoxia was modulated by caffeine in a similar concentration-specific manner. Caffeine at 1 mM, but not at the 0.05 mM concentration decreased the G2 arrest in these cells. Taken together this study shows the novel funding that caffeine has a concentration-specific effect on cell cycle regulation, ROS generation, and cell survival in hyperoxic conditions.

  11. Neuronal cells but not muscle cells are resistant to oxidative stress mediated protein misfolding and cell death: role of molecular chaperones.

    Science.gov (United States)

    Bhattacharya, Arunabh; Wei, Rochelle; Hamilton, Ryan T; Chaudhuri, Asish R

    2014-04-18

    Our recent study in a mouse model of familial-Amyotrophic Lateral Sclerosis (f-ALS) revealed that muscle proteins are equally sensitive to misfolding as spinal cord proteins despite the presence of low mutant CuZn-superoxide dismutase, which is considered to be the key toxic element for initiation and progression of f-ALS. More importantly, we observed differential level of heat shock proteins (Hsp's) between skeletal muscle and spinal cord tissues prior to the onset and during disease progression; spinal cord maintains significantly higher level of Hsp's compared to skeletal muscle. In this study, we report two important observations; (i) muscle cells (but not neuronal cells) are extremely vulnerable to protein misfolding and cell death during challenge with oxidative stress and (ii) muscle cells fail to mount Hsp's during challenge unlike neuronal cells. These two findings can possibly explain why muscle atrophy precedes the death of motor neurons in f-ALS mice.

  12. Role of oxidative stress in ethanol induced germ cell apoptosis — An experimental study in rats

    OpenAIRE

    Maneesh, M.; Jayalekshmi, H; Dutta, Sanjiba; Chakrabarti, Amit; Vasudevan, D. M.

    2005-01-01

    The study was undertaken to evaluate the possible involvement of oxidative stress in the pathogenesis of ethanol induced testicular atrophy in rats. Adult male rats were orally administered ethanol at a dose of 1.6 g/kg body weight/day for four weeks. Twenty-four hours after the last treatment the rats were sacrificed using anesthetic ether. Testes were removed and weighed. Apoptosis was studied by using the Feulgen reaction on 5 μ thin paraffin sections of testis. Testicular homogenate was p...

  13. Quercetin and sesamin protect neuronal PC12 cells from high-glucose-induced oxidation, nitrosative stress, and apoptosis.

    Science.gov (United States)

    Bournival, Julie; Francoeur, Marc-André; Renaud, Justine; Martinoli, Maria-Grazia

    2012-06-01

    Complications of diabetes are now well-known to affect sensory, motor, and autonomic nerves. Diabetes is also thought to be involved in neurodegenerative processes characteristic of several neurodegenerative diseases. Indeed, it has been acknowledged recently that hyperglycemia-induced oxidative stress contributes to numerous cellular reactions typical of central nervous system deterioration. The goal of the present study was to evaluate the effects of the polyphenol quercetin and the lignan sesamin on high-glucose (HG)-induced oxidative damage in an in vitro model of dopaminergic neurons, neuronal PC12 cells. When incubated with HG (13.5 mg/mL), neuronal PC12 cells showed a significant increase of cellular death. Our results revealed that quercetin and sesamin defend neuronal PC12 cells from HG-induced cellular demise. An elevated level of reactive oxygen and nitrogen species is a consequence of improved oxidative stress after HG administration, and we demonstrated that this production diminishes with quercetin and sesamin treatment. We also found that quercetin and sesamin elicited an increment of superoxide dismutase activity. DNA fragmentation, Bax/Bcl-2 ratio, nuclear translocation of apoptosis-inducing factor, as well as poly(adenosine diphosphate [ADP]-ribose) polymerase cleavage were significantly reduced by quercetin and sesamin administration, affirming their antiapoptotic features. Also, HG treatment impacted caspase-3 cleavage, supporting caspase-3-dependent pathways as mechanisms of apoptotic death. Our results indicate a powerful role for these natural dietary compounds and emphasize preventive or complementary nutritional strategies for diabetes control.

  14. Selenium methylselenocysteine protects human hepatoma HepG2 cells against oxidative stress induced by tert-butyl hydroperoxide.

    Science.gov (United States)

    Cuello, Susana; Ramos, Sonia; Mateos, Raquel; Martín, M Angeles; Madrid, Yolanda; Cámara, Carmen; Bravo, Laura; Goya, Luis

    2007-12-01

    Selenium methylselenocysteine (Se-MeSeCys) is a common selenocompound in the diet with a tested chemopreventive effect. This study investigated the potential protective effect of Se-MeSeCys against a chemical oxidative stress induced by tert-butyl hydroperoxide (t-BOOH) on human hepatoma HepG2 cells. Speciation of selenium derivatives by liquid chromatography-inductively coupled plasma mass spectrometry depicts Se-MeSeCys as the only selenocompound in the cell culture. Cell viability (lactate dehydrogenase) and markers of oxidative status--concentration of reduced glutathione (GSH) and malondialdehyde (MDA), generation of reactive oxygen species (ROS) and activity of the antioxidant enzymes glutathione peroxidase (GPx) and glutathione reductase (GR)--were evaluated. Pretreatment of cells with Se-MeSeCys for 20 h completely prevented the enhanced cell damage, MDA concentration and GR and GPx activity and the decreased GSH induced by t-BOOH but did not prevent increased ROS generation. The results show that treatment of HepG2 cells with concentrations of Se-MeSeCys in the nanomolar to micromolar range confers a significant protection against an oxidative insult.

  15. Endothelial and smooth muscle cells from abdominal aortic aneurysm have increased oxidative stress and telomere attrition.

    Directory of Open Access Journals (Sweden)

    Giuseppe Cafueri

    Full Text Available BACKGROUND: Abdominal aortic aneurysm (AAA is a complex multi-factorial disease with life-threatening complications. AAA is typically asymptomatic and its rupture is associated with high mortality rate. Both environmental and genetic risk factors are involved in AAA pathogenesis. Aim of this study was to investigate telomere length (TL and oxidative DNA damage in paired blood lymphocytes, aortic endothelial cells (EC, vascular smooth muscle cells (VSMC, and epidermal cells from patients with AAA in comparison with matched controls. METHODS: TL was assessed using a modification of quantitative (Q-FISH in combination with immunofluorescence for CD31 or α-smooth muscle actin to detect EC and VSMC, respectively. Oxidative DNA damage was investigated by immunofluorescence staining for 7, 8-dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dG. RESULTS AND CONCLUSIONS: Telomeres were found to be significantly shortened in EC, VSMC, keratinocytes and blood lymphocytes from AAA patients compared to matched controls. 8-oxo-dG immunoreactivity, indicative of oxidative DNA damage, was detected at higher levels in all of the above cell types from AAA patients compared to matched controls. Increased DNA double strand breaks were detected in AAA patients vs controls by nuclear staining for γ-H2AX histone. There was statistically significant inverse correlation between TL and accumulation of oxidative DNA damage in blood lymphocytes from AAA patients. This study shows for the first time that EC and VSMC from AAA have shortened telomeres and oxidative DNA damage. Similar findings were obtained with circulating lymphocytes and keratinocytes, indicating the systemic nature of the disease. Potential translational implications of these findings are discussed.

  16. Data concerning the proteolytic resistance and oxidative stress in LAN5 cells after treatment with BSA hydrogels

    Directory of Open Access Journals (Sweden)

    Pasquale Picone

    2016-12-01

    Full Text Available Proteolytic resistance is a relevant aspect to be tested in the formulation of new nanoscale biomaterials. The action of proteolytic enzymes is a very fast process occurring in the range of few minutes. Here, we report data concerning the proteolytic resistance of a heat-set BSA hydrogel obtained after 20-hour incubation at 60 °C prepared at the pH value of 3.9, pH at which the hydrogel presents the highest elastic character with respect to gel formed at pH 5.9 and 7.4 “Heat-and pH-induced BSA conformational changes, hydrogel formation and application as 3D cell scaffold” (G. Navarra, C. Peres, M. Contardi, P. Picone, P.L. San Biagio, M. Di Carlo, D. Giacomazza, V. Militello, 2016 [1]. We show that the BSA hydrogel produced by heating treatment is protected by the action of proteinase K enzyme. Moreover, we show that LAN5 cells cultured in presence of BSA hydrogels formed at pH 3.9, 5.9 and 7.4 did not exhibit any oxidative stress, one of the first and crucial events causing cell death “Are oxidative stress and mitochondrial dysfunction the key players in the neurodegenerative diseases?” (M. Di Carlo, D. Giacomazza, P. Picone, D. Nuzzo, P.L. San Biagio, 2012 [2] “Effect of zinc oxide nanomaterials induced oxidative stress on the p53 pathway” (M.I. Setyawati, C.Y. Tay, D.T. Leaong, 2013 [3].

  17. Acetaldehyde Induces Cytotoxicity of SH-SY5Y Cells via Inhibition of Akt Activation and Induction of Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Tingting Yan

    2016-01-01

    Full Text Available Excessive alcohol consumption can lead to brain tissue damage and cognitive dysfunction. It has been shown that heavy drinking is associated with an earlier onset of neurodegenerative diseases such as Alzheimer’s disease. Acetaldehyde, the most toxic metabolite of ethanol, is speculated to mediate the brain tissue damage and cognitive dysfunction induced by the chronic excessive consumption of alcohol. However, the exact mechanisms by which acetaldehyde induces neurotoxicity are not totally understood. In this study, we investigated the cytotoxic effects of acetaldehyde in SH-SY5Y cells and found that acetaldehyde induced apoptosis of SH-SY5Y cells by downregulating the expression of antiapoptotic Bcl-2 and Bcl-xL and upregulating the expression of proapoptotic Bax. Acetaldehyde treatment led to a significant decrease in the levels of activated Akt and cyclic AMP-responsive element binding protein (CREB. In addition, acetaldehyde induced the activation of p38 mitogen-activated protein kinase (MAPK while inhibiting the activation of extracellular signal-regulated kinases (ERKs, p44/p42MAPK. Meanwhile, acetaldehyde treatment caused an increase in the production of reactive oxygen species and elevated the oxidative stress in SH-SY5Y cells. Therefore, acetaldehyde induces cytotoxicity of SH-SY5Y cells via promotion of apoptotic signaling, inhibition of cell survival pathway, and induction of oxidative stress.

  18. Chaperones, but not oxidized proteins, are ubiquitinated after oxidative stress

    DEFF Research Database (Denmark)

    Kästle, Marc; Reeg, Sandra; Rogowska-Wrzesinska, Adelina;

    2012-01-01

    After oxidative stress proteins which are oxidatively modified are degraded by the 20S proteasome. However, several studies documented an enhanced ubiquitination of yet unknown proteins. Since ubiqutination is a prerequisite for degradation by the 26S proteasome in an ATP-dependent manner......, we were able to confirm an increase of ubiquitinated proteins 16h upon oxidative stress. Therefore, we isolated ubiquitinated proteins from hydrogen peroxide treated cells, as well as from control and lactacystin, an irreversible proteasome inhibitor, treated cells, and identified some......, ubiquitinated proteins confirm the thesis that ubiquitination upon oxidative stress is no random process to degrade the mass of oxidized proteins, but concerns a special group of functional proteins....

  19. The effect of aging on the DNA damage and repair capacity in 2BS cells undergoing oxidative stress.

    Science.gov (United States)

    Wang, Jin-Ling; Wang, Pei-Chang

    2012-01-01

    Aging is associated with a reduction in the DNA repair capacity under oxidative stress. However, whether the DNA damage and repair capacity can be a biomarker of aging remains controversial. In this study, we demonstrated two cause-and-effect relationships, the one is between the DNA damage and repair capacity and the cellular age, another is between DNA damage and repair capacity and the level of oxidative stress in human embryonic lung fibroblasts (2BS) exposed to different doses of hydrogen peroxide (H2O2). To clarify the mechanisms of the age-related reduction in DNA damage and repair capacity, we preliminarily evaluated the expressions of six kinds of pivotal enzymes involved in the two classical DNA repair pathways. The DNA repair capacity was observed in human fibroblasts cells using the comet assay; the age-related DNA repair enzymes were selected by RT-PCR and then verified by Western blot in vitro. Results showed that the DNA repair capacity was negatively and linearly correlated with (i) cumulative population doubling (PD) levels only in the group of low concentration of hydrogen peroxide treatment, (ii) with the level of oxidative stress only in the group of young PD cells. The mRNA expression of DNA polymerase δ1 decreased substantially in senescent cells and showed negative linear-correlation with PD levels; the protein expression level was well consistent with the mRNA level. Taken together, DNA damage and repair capacity can be a biomarker of aging. Reduced expression of DNA polymerase δ1 may be responsible for the decrease of DNA repair capacity in senescent cells.

  20. Myocardial dysfunction in patients with type 2 diabetes mellitus: role of endothelial progenitor cells and oxidative stress

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    Zhao Chun

    2012-12-01

    Full Text Available Abstract Background Endothelial progenitor cells (EPCs are responsible for angiogenesis and maintenance of microvascular integrity, the number of EPCs is correlated with oxidative stress. Their relation to myocardial dysfunction in patients with type 2 diabetes mellitus (T2DM is nonetheless unknown. Methods Eighty-seven patients with T2DM and no history of coronary artery disease were recruited. Transthoracic echocardiography and detailed evaluation of left ventricular (LV systolic function by 2-dimensional (2D speckle tracking derived strain analysis in 3 orthogonal directions was performed. Four subpopulations of EPCs, including CD34+, CD133+, CD34+/kinase insert domain-containing receptor (KDR + and CD133+/KDR + EPCs, were measured by flow cytometry. Oxidative stress was assessed by superoxide dismutase (SOD. Results The mean age of the patients was 62 ± 9 years and 39.6% were male. Those with an impaired longitudinal strain had a lower number of CD34+ EPCs (2.82 ± 1.87% vs. 3.74 ± 2.12%, P  Conclusions LV global circumferential strain was independently associated with number of CD34+ EPCs and SOD. These findings suggest that myocardial dysfunction in patients with T2DM is related to depletion of EPCs and increased oxidative stress.

  1. Molecular basis for vulnerability to mitochondrial and oxidative stress in a neuroendocrine CRI-G1 cell line.

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    Natasha Chandiramani

    Full Text Available BACKGROUND: Many age-associated disorders (including diabetes, cancer, and neurodegenerative diseases are linked to mitochondrial dysfunction, which leads to impaired cellular bioenergetics and increased oxidative stress. However, it is not known what genetic and molecular pathways underlie differential vulnerability to mitochondrial dysfunction observed among different cell types. METHODOLOGY/PRINCIPAL FINDINGS: Starting with an insulinoma cell line as a model for a neuronal/endocrine cell type, we isolated a novel subclonal line (named CRI-G1-RS that was more susceptible to cell death induced by mitochondrial respiratory chain inhibitors than the parental CRI-G1 line (renamed CRI-G1-RR for clarity. Compared to parental RR cells, RS cells were also more vulnerable to direct oxidative stress, but equally vulnerable to mitochondrial uncoupling and less vulnerable to protein kinase inhibition-induced apoptosis. Thus, differential vulnerability to mitochondrial toxins between these two cell types likely reflects differences in their ability to handle metabolically generated reactive oxygen species rather than differences in ATP production/utilization or in downstream apoptotic machinery. Genome-wide gene expression analysis and follow-up biochemical studies revealed that, in this experimental system, increased vulnerability to mitochondrial and oxidative stress was associated with (1 inhibition of ARE/Nrf2/Keap1 antioxidant pathway; (2 decreased expression of antioxidant and phase I/II conjugation enzymes, most of which are Nrf2 transcriptional targets; (3 increased expression of molecular chaperones, many of which are also considered Nrf2 transcriptional targets; (4 increased expression of β cell-specific genes and transcription factors that specify/maintain β cell fate; and (5 reconstitution of glucose-stimulated insulin secretion. CONCLUSIONS/SIGNIFICANCE: The molecular profile presented here will enable identification of individual genes or

  2. Heat and oxidative stress alter the expression of orexin and its related receptors in avian liver cells.

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    Greene, Elizabeth; Khaldi, Stephanie; Ishola, Peter; Bottje, Walter; Ohkubo, Takeshi; Anthony, Nicholas; Dridi, Sami

    2016-01-01

    Orexins (A and B) or hypocretins (1 and 2) are hypothalamic orexigenic neuropeptides that are involved in the regulation of several physiological processes in mammals. Recently, orexin has been shown to activate the hypothalamic-pituitary-adrenal (HPA) stress axis and emerging evidences identify it as a stress modulator in mammals. However, the regulation of orexin system by stress itself remains unclear. Here, we investigate the effects of heat, 4-Hydroxynonenal (4-HNE) and hydrogen peroxide (H2O2) stress on the hepatic expression of orexin (ORX) and its related receptors (ORXR1/2) in avian species. Using in vivo and in vitro models, we found that heat stress significantly down-regulated ORX and ORXR1/2 mRNA and protein abundances in quail liver and LMH cells. H2O2, however, decreased ORX protein and increased ORX mRNA levels in a dose dependent manner (Porexin mRNA and protein levels suggests that H2O2 treatment modulates post-transcriptional mechanisms. 4-HNE had a biphasic effect on orexin system expression, with a significant up-regulation at low doses (10 and 20μM) and a significant down-regulation at a high dose (30μM). Taken together, our data indicated that hepatic orexin system could be a molecular signature in the heat and oxidative stress response.

  3. Nitro-oxidative Stress Is Involved in Anticancer Activity of 17β-Estradiol Derivative in Neuroblastoma Cells.

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    Gorska, Magdalena; Kuban-Jankowska, Alicja; Milczarek, Ryszard; Wozniak, Michal

    2016-04-01

    Neuroblastoma is one of the most common childhood malignancies and the primary cause of death from pediatric cancer. Derivatives of 17β-estradiol, 2-methoxyestradiol, as well as selective estrogen receptor modulators, such as fulvestrant, are novel potentially active anticancer agents. In particular, 2-methoxyestradiol is effective in treatment of numerous malignancies, including breast and prostate cancer, Ewing sarcoma, and osteosarcoma. Herein, we treated neuroblastoma SH-SY5Y cells with physiologically and pharmacologically relevant concentrations of 2-methoxyestradiol. We used flow cytometry in order to determine cell viability, cell death, level of nitric oxide and mitochondrial membrane potential. We demonstrated that at pharmacologically relevant concentrations, 2-methoxyestradiol results in induction of apoptosis of neuroblastoma SH-SY5Y cells via nitric oxide generation and reduction of mitochondrial membrane potential. Based on the obtained data, we propose that 2-methoxyestradiol may be a natural modulator of cancer cell death and survival through nitro-oxidative stress-dependent mechanisms. Moreover, the results confirm the efficiency of 2-methoxyestradiol in treatment of neuroblastoma.

  4. Development and characterization of a hydrogen peroxide-resistant cholangiocyte cell line: A novel model of oxidative stress-related cholangiocarcinoma genesis

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    Thanan, Raynoo [Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Techasen, Anchalee [Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Faculty of Associated Medical Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Hou, Bo [Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Tsu, Mie 514-8507 (Japan); Jamnongkan, Wassana; Armartmuntree, Napat [Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Yongvanit, Puangrat, E-mail: puangrat@kku.ac.th [Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002 (Thailand); Murata, Mariko, E-mail: mmurata@doc.medic.mie-u.ac.jp [Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Tsu, Mie 514-8507 (Japan)

    2015-08-14

    Oxidative stress is a cause of inflammation–related diseases, including cancers. Cholangiocarcinoma is a liver cancer with bile duct epithelial cell phenotypes. Our previous studies in animal and human models indicated that oxidative stress is a major cause of cholangiocarcinoma development. Hydrogen peroxide (H{sub 2}O{sub 2}) can generate hydroxyl radicals, which damage lipids, proteins, and nucleic acids, leading to cell death. However, some cells can survive by adapting to oxidative stress conditions, and selective clonal expansion of these resistant cells would be involved in oxidative stress-related carcinogenesis. The present study aimed to establish H{sub 2}O{sub 2}-resistant cell line from an immortal cholangiocyte cell line (MMNK1) by chronic treatment with low-concentration H{sub 2}O{sub 2} (25 μM). After 72 days of induction, H{sub 2}O{sub 2}-resistant cell lines (ox-MMNK1-L) were obtained. The ox-MMNK1-L cell line showed H{sub 2}O{sub 2}-resistant properties, increasing the expression of the anti-oxidant genes catalase (CAT), superoxide dismutase-1 (SOD1), superoxide dismutase-2 (SOD2), and superoxide dismutase-3 (SOD3) and the enzyme activities of CAT and intracellular SODs. Furthermore, the resistant cells showed increased expression levels of an epigenetics-related gene, DNA methyltransferase-1 (DNMT1), when compared to the parental cells. Interestingly, the ox-MMNK1-L cell line had a significantly higher cell proliferation rate than the MMNK1 normal cell line. Moreover, ox-MMNK1-L cells showed pseudopodia formation and the loss of cell-to-cell adhesion (multi-layers) under additional oxidative stress (100 μM H{sub 2}O{sub 2}). These findings suggest that H{sub 2}O{sub 2}-resistant cells can be used as a model of oxidative stress-related cholangiocarcinoma genesis through molecular changes such as alteration of gene expression and epigenetic changes. - Highlights: • An H{sub 2}O{sub 2}-resistant ox-MMNK1-L cells was established from

  5. [Cyclosporin A causes oxidative stress and mitochondrial dysfunction in renal tubular cells].

    Science.gov (United States)

    Pérez de Hornedo, J; de Arriba, G; Calvino, M; Benito, S; Parra, T

    2007-01-01

    Reactive oxygen species (ROS) have been implicated in cyclosporin A (CsA) nephrotoxicity. As mitochondria are one of the main sources of ROS in cells, we evaluated the role of CsA in mitochondrial structure and function in LLC-PK1 cells. We incubated cells with CsA 1 microM for 24 hours and studies were performed with flow citometry and confocal microscopy. We studied mitochondrial NAD(P)H content, superoxide anion (O2.-) production (MitoSOX Red), oxidation of cardiolipin of inner mitochondrial membrane (NAO) and mitochondrial membrane potential (DIOC2(3)). Also we analyzed the intracellular ROS synthesis (H2DCF-DA) and reduced glutation (GSH) of cells. Our results showed that CsA decreased NAD(P)H and membrane potential, and increased O2.- in mitochondria. CsA also provoked oxidation of cardiolipin. Furthermore, CsA increased intracellular ROS production and decreased GSH content. These results suggest that CsA has crucial effects in mitochondria. CsA modified mitochondrial physiology through the decrease of antioxidant mitochondrial compounds as NAD(P)H and the dissipation of mitochondrial membrane potential and increase of oxidants as O2.-. Also, CsA alters lipidic structure of inner mitochondrial membrane through the oxidation of cardiolipin. These effects trigger a chain of events that favour intracellular synthesis of ROS and depletion of GSH that can compromise cellular viability. Nephrotoxic cellular effects of CsA can be explained, at least in part, through its influence on mitochondrial functionalism.

  6. Functionalized Mesoporous Silica Nanoparticle with Antioxidants as a New Carrier That Generates Lower Oxidative Stress Impact on Cells.

    Science.gov (United States)

    Ebabe Elle, Raymond; Rahmani, Saher; Lauret, Céline; Morena, Marion; Bidel, Luc Philippe Régis; Boulahtouf, Abdelhay; Balaguer, Patrick; Cristol, Jean-Paul; Durand, Jean-Olivier; Charnay, Clarence; Badia, Eric

    2016-08-01

    Mesoporous silica nanoparticles (MSNs) were covalently coated with antioxidant molecules, namely, caffeic acid (MSN-CAF) or rutin (MSN-RUT), in order to diminish the impact of oxidative stress induced after transfection into cells, thus generating safer carriers used for either drug delivery or other applications. Two cellular models involved in the entry of NPs in the body were used for this purpose: the intestinal Caco-2 and the epidermal HaCaT cell lines. Rutin gave the best results in terms of antioxidant capacities preservation during coupling procedures, cellular toxicity alleviation, and decrease of ROS level after 24 h incubation of cells with grafted nanoparticles. These protective effects of rutin were found more pronounced in HaCaT than in Caco-2 cells, indicating some cellular specificity toward defense against oxidative stress. In order to gain more insight about the Nrf2 response, a stable transfected HaCaT cell line bearing repeats of the antioxidant response element (ARE) in front of a luciferase reporter gene was generated. In this cell line, both tBHQ and quercetin (Nrf2 agonists), but not rutin, were able to induce, in a dose-dependent fashion, the luciferase response. Interestingly, at high concentration, MSN-RUT was able to induce a strong Nrf2 protective response in HaCaT cells, accompanied by a comparable induction of HO-1 mRNA. The level of these responses was again less important in Caco-2 cells. To conclude, in keratinocyte cell line, the coupling of rutin to silica nanoparticles was beneficial in term of ROS reduction, cellular viability, and protective effects mediated through the activation of the Nrf2 antioxidant pathway.

  7. Cystine accumulation attenuates insulin release from the pancreatic β-cell due to elevated oxidative stress and decreased ATP levels.

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    McEvoy, Bernadette; Sumayao, Rodolfo; Slattery, Craig; McMorrow, Tara; Newsholme, Philip

    2015-12-01

    The pancreatic β-cell has reduced antioxidant defences making it more susceptible to oxidative stress. In cystinosis, a lysosomal storage disorder, an altered redox state may contribute to cellular dysfunction. This rare disease is caused by an abnormal lysosomal cystine transporter, cystinosin, which causes excessive accumulation of cystine in the lysosome. Cystinosis associated kidney damage and dysfunction leads to the Fanconi syndrome and ultimately end-stage renal disease. Following kidney transplant, cystine accumulation in other organs including the pancreas leads to multi-organ dysfunction. In this study, a Ctns gene knockdown model of cystinosis was developed in the BRIN-BD11 rat clonal pancreatic β-cell line using Ctns-targeting siRNA. Additionally there was reduced cystinosin expression, while cell cystine levels were similarly elevated to the cystinotic state. Decreased levels of chronic (24 h) and acute (20 min) nutrient-stimulated insulin secretion were observed. This decrease may be due to depressed ATP generation particularly from glycolysis. Increased ATP production and the ATP/ADP ratio are essential for insulin secretion. Oxidised glutathione levels were augmented, resulting in a lower [glutathione/oxidised glutathione] redox potential. Additionally, the mitochondrial membrane potential was reduced, apoptosis levels were elevated, as were markers of oxidative stress, including reactive oxygen species, superoxide and hydrogen peroxide. Furthermore, the basal and activated phosphorylated forms of the redox-sensitive transcription factor NF-κB were increased in cells with silenced Ctns. From this study, the cystinotic-like pancreatic β-cell model demonstrated that the altered oxidative status of the cell, resulted in depressed mitochondrial function and pathways of ATP production, causing reduced nutrient-stimulated insulin secretion.

  8. Melatonin prevents dexamethasone-induced testicular oxidative stress and germ cell apoptosis in golden hamster, Mesocricetus auratus.

    Science.gov (United States)

    Mukherjee, Arun; Haldar, Chandana; Vishwas, Dipanshu Kumar

    2015-10-01

    This study investigated the protective effect of melatonin on dexamethasone (Dex), an extensively used anti-inflammatory and immunosuppressive synthetic glucocorticoid, induced testicular oxidative stress and germ cell apoptosis in golden hamster. Hamsters were randomly divided into four groups (n = 7): group I - control; group II - melatonin treated (10 mg kg(-1)  day(-1) ); group III - Dex treated (7 mg kg(-1)  day(-1) ) and group IV - combination of Dex and melatonin. All the injections were administered intraperitoneally for seven consecutive days. The histopathological changes, specific biochemical markers, including antioxidative enzymes, plasma melatonin level and the markers for germ cell apoptosis were evaluated. Dex administration decreased antioxidant enzyme activities (SOD, CAT, GSH-PX ), plasma melatonin level and melatonin receptor (MT1) expression with a concomitant increase in lipid peroxidation (TBARS) and altered testicular histopathology which might culminate into increased germ cell apoptosis as evident from increased Bax/Bcl-2 ratio and caspase-3 expression. However, melatonin pre-treatment enhanced enzyme activities for SOD, CAT, GSH-PX with a simultaneous decrease in Bax/Bcl-2 ratio and caspase-3 expression. Our findings clearly suggest that melatonin improved defence against Dex-induced testicular oxidative stress and prevented germ cell apoptosis, suggesting a novel combination therapeutic approach for management of male reproductive health.

  9. The oxidative stress response in yeast cells involves changes in the stability of Aft1 regulon mRNAs.

    Science.gov (United States)

    Castells-Roca, Laia; Mühlenhoff, Ulrich; Lill, Roland; Herrero, Enrique; Bellí, Gemma

    2011-07-01

    Saccharomyces cerevisiae can import iron through a high-affinity system consisting of the Ftr1/Fet3-mediated reductive pathway and the siderophore-mediated non-reductive one. Expression of components of the high-affinity system is controlled by the Aft1 transcriptional factor. In this study we show that, upon oxidative stress, Aft1 is transitorily internalized into the nucleus, followed by transcription activation of components of its regulon. In these conditions, the mRNA levels of the genes of the non-reductive pathway become increased, while those of FTR1 and FET3 remain low because of destabilization of the mRNAs. Consequently, the respective protein levels also remain low. Such mRNA destabilization is mediated by the general 5'-3' mRNA decay pathway and is independent of the RNA binding protein Cth2. Yeast cells are hypersensitive to peroxides in growth conditions where only the high-affinity reductive pathway is functional for iron assimilation. On the contrary, peroxide does not affect growth when iron uptake occurs exclusively through the non-reductive pathway. This reinforces the idea that upon oxidative stress S. cerevisiae cells redirect iron assimilation through the non-reductive pathway to minimize oxidative damage by the ferrous ions, which are formed during iron import through the Ftr1/Fet3 complexes.

  10. PI-PLCβ1b affects Akt activation, cyclin E expression, and caspase cleavage, promoting cell survival in pro-B-lymphoblastic cells exposed to oxidative stress.

    Science.gov (United States)

    Piazzi, Manuela; Blalock, William L; Bavelloni, Alberto; Faenza, Irene; Raffini, Mirco; Tagliavini, Francesca; Manzoli, Lucia; Cocco, Lucio

    2015-04-01

    The phosphoinositide-dependent signal transduction pathway has been implicated in the control of a variety of biologic processes, such as the regulation of cellular metabolism and homeostasis, cell proliferation and differentiation, and apoptosis. One of the key players in the regulation of inositol lipid signaling is the phospholipase Cβ1 (PI-PLCβ1), that hydrolyzes phosphatidylinositol 4,5-bisphosphate [PtIns(4,5)P2], giving rise to the second messengers inositol triphosphate and diacylglicerol. PI-PLCβ1 has been associated with the regulation of several cellular functions, some of which have not yet been fully understood. In particular, it has been reported that PI-PLCβ1 protects murine fibroblasts from oxidative stress-induced cell death. The mediators of oxidative stress, reactive oxygen species (ROS), have been shown to regulate major epigenetic processes, causing the silencing of tumor suppressors and enhancing the proliferation of leukemic cells under oxidative stress. Investigation of the interplay between ROS, PI-PLCβ1, and their signaling mediators in leukemia might therefore reveal innovative targets of pharmacological therapy in the treatment for leukemia. In this work, we demonstrate that in pro-B-lymphoblastic cells (Ba/F3), treated with H2O2, PI-PLCβ1b conferred resistance to cell death, promoting cell cycle progression and cell proliferation and influencing the expression of cyclin A and E. Interestingly, we found that, expression of PI-PLCβ1b affects the activity of caspase-3, caspase-7, and of several protein kinases induced by oxidative stress. In particular, PI-PLCβ1b expression completely abolished the phosphorylation of Erk1/2 MAP kinases, down-regulated phosphatase and tensin homolog (PTEN), and up-regulated the phosphorylation of Akt, thereby sustaining cellular proliferation.

  11. Genotoxicity of ferric oxide nanoparticles in Raphanus sativus: Deciphering the role of signaling factors, oxidative stress and cell death.

    Science.gov (United States)

    Saquib, Quaiser; Faisal, Mohammad; Alatar, Abdulrahman A; Al-Khedhairy, Abdulaziz A; Ahmed, Mukhtar; Ansari, Sabiha M; Alwathnani, Hend A; Okla, Mohammad K; Dwivedi, Sourabh; Musarrat, Javed; Praveen, Shelly; Khan, Shams T; Wahab, Rizwan; Siddiqui, Maqsood A; Ahmad, Javed

    2016-09-01

    We have studied the genotoxic and apoptotic potential of ferric oxide nanoparticles (Fe2O3-NPs) in Raphanus sativus (radish). Fe2O3-NPs retarded the root length and seed germination in radish. Ultrathin sections of treated roots showed subcellular localization of Fe2O3-NPs, along with the appearance of damaged mitochondria and excessive vacuolization. Flow cytometric analysis of Fe2O3-NPs (1.0mg/mL) treated groups exhibited 219.5%, 161%, 120.4% and 161.4% increase in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), nitric oxide (NO) and Ca(2+) influx in radish protoplasts. A concentration dependent increase in the antioxidative enzymes glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (LPO) has been recorded. Comet assay showed a concentration dependent increase in deoxyribonucleic acid (DNA) strand breaks in Fe2O3-NPs treated groups. Cell cycle analysis revealed 88.4% of cells in sub-G1 apoptotic phase, suggesting cell death in Fe2O3-NPs (2.0mg/mL) treated group. Taking together, the genotoxicity induced by Fe2O3-NPs highlights the importance of environmental risk associated with improper disposal of nanoparticles (NPs) and radish can serve as a good indicator for measuring the phytotoxicity of NPs grown in NP-polluted environment.

  12. Can Melatonin Act as an Antioxidant in Hydrogen Peroxide-Induced Oxidative Stress Model in Human Peripheral Blood Mononuclear Cells?

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    Solaleh Emamgholipour

    2016-01-01

    Full Text Available Purpose. We aimed to investigate the possible effects of melatonin on gene expressions and activities of MnSOD and catalase under conditions of oxidative stress induced by hydrogen peroxide (H2O2 in peripheral blood mononuclear cells (PBMCs. Materials and Methods. PBMCs were isolated from healthy subjects and treated as follows: (1 control (only with 0.1% DMSO for 12 h; (2 melatonin (1 mM for 12 h; (3 H2O2 (250 μM for 2 h; (4 H2O2 (250 μM for 2 h following 10 h pretreatment with melatonin (1 mM. The gene expression was evaluated by real-time PCR. MnSOD and catalase activities in PBMCs were determined by colorimetric assays. Results. Pretreatment of PBMCs with melatonin significantly augmented expression and activity of MnSOD which were diminished by H2O2. Melatonin treatment of PBMCs caused a significant upregulation of catalase by almost 2-fold in comparison with untreated cells. However, activity and expression of catalase increased by 1.5-fold in PBMCs under H2O2-induced oxidative stress compared with untreated cell. Moreover, pretreatment of PBMCs with melatonin resulted in a significant 1.8-fold increase in catalase expression compared to PBMCs treated only with H2O2. Conclusion. It seems that melatonin could prevent from undesirable impacts of H2O2-induced oxidative stress on MnSOD downregulation. Moreover, melatonin could promote inductive effect of H2O2 on catalase mRNA expression.

  13. Aluminium oxide nanoparticles induce mitochondrial-mediated oxidative stress and alter the expression of antioxidant enzymes in human mesenchymal stem cells.

    Science.gov (United States)

    Alshatwi, Ali A; Subbarayan, Periasamy Vaiyapuri; Ramesh, E; Al-Hazzani, Amal A; Alsaif, Mohammed A; Alwarthan, Abdulrahman A

    2013-01-01

    An urgent need for toxicological studies on aluminium oxide nanoparticles (Al(2) [Formula: see text]NPs) has arisen from their rapidly emerging range of applications in the food and agricultural sectors. Despite the widespread use of nanoscale aluminium and its composites in the food industry, there is a serious lack of information concerning the biological activities of Al(2) [Formula: see text]NPs (ANPs) and their impact on human health. In this preliminary study, the effects of ANPs on metabolic stress in human mesenchymal stem cells (hMSCs) were analysed. The results showed dose-dependent effects, including cellular toxicity. The mitochondrial membrane potential in the hMSCs decreased with increasing ANP concentrations after 24 h of exposure. The expression levels of oxidative stress-responsive enzymes were monitored by RT-PCR. The expression levels of CYP1A and POR were up-regulated in response to ANPs, and a significant down-regulation in the expression of the antioxidant enzyme SOD was observed. Further, dose-dependent changes in the mRNA levels of GSTM3, GPX and GSR were noted. These findings suggest that the toxicity of ANPs in hMSCs may be mediated through an increase in oxidative stress. The results of this study clearly demonstrate the nanotoxicological effects of ANPs on hMSCs, which will be useful for nanotoxicological indexing.

  14. Ganoderma Lucidum polysaccharides protect against MPP+ and rotenone-induced apoptosis in primary dopaminergic cell cultures through inhibiting oxidative stress

    Science.gov (United States)

    Guo, Shan-Shan; Cui, Xiao-Lan; Rausch, Wolf-Dieter

    2016-01-01

    Oxidative stress plays a pivotal role in the progressive neurodegeneration in Parkinson’s disease (PD) which is responsible for disabling motor abnormalities in more than 6.5 million people worldwide. Polysaccharides are the main active constituents from Ganoderma lucidum which is characterized with anti-oxidant, antitumor and immunostimulant properties. In the present study, primary dopaminergic cell cultures prepared from embryonic mouse mesencephala were used to investigate the neuroprotective effects and the potential mechanisms of Ganoderma lucidum polysaccharides (GLP) on the degeneration of dopaminergic neurons induced by the neurotoxins methyl-4-phenylpyridine (MPP+) and rotenone. Results revealed that GLP can protect dopamine neurons against MPP+ and rotenone at the concentrations of 100, 50 and 25 μg/ml in primary mesencephalic cultures in a dose-dependent manner. Interestingly, either with or without neurotoxin treatment, GLP treatment elevated the survival of THir neurons, and increased the length of neurites of dopaminergic neurons. The Trolox equivalent anti-oxidant capacity (TEAC) of GLP was determined to be 199.53 μmol Trolox/g extract, and the decrease of mitochondrial complex I activity induced by MPP+ and rotenone was elevated by GLP treatment (100, 50, 25 and 12.5 μg/ml) in a dose dependent manner. Furthermore, GLP dramatically decreased the relative number of apoptotic cells and increased the declining mitochondrial membrane potential (ΔΨm) induced by MPP+ and rotenone in a dose-dependent manner. In addition, GLP treatment reduced the ROS formation induced by MPP+ and rotenone at the concentrations of 100, 50 and 25 μg/ml in a dose-dependent manner. Our study indicates that GLP possesses neuroprotective properties against MPP+ and rotenone neurotoxicity through suppressing oxidative stress in primary mesencephalic dopaminergic cell culture owning to its antioxidant activities. PMID:27335703

  15. Ganoderma Lucidum polysaccharides protect against MPP(+) and rotenone-induced apoptosis in primary dopaminergic cell cultures through inhibiting oxidative stress.

    Science.gov (United States)

    Guo, Shan-Shan; Cui, Xiao-Lan; Rausch, Wolf-Dieter

    2016-01-01

    Oxidative stress plays a pivotal role in the progressive neurodegeneration in Parkinson's disease (PD) which is responsible for disabling motor abnormalities in more than 6.5 million people worldwide. Polysaccharides are the main active constituents from Ganoderma lucidum which is characterized with anti-oxidant, antitumor and immunostimulant properties. In the present study, primary dopaminergic cell cultures prepared from embryonic mouse mesencephala were used to investigate the neuroprotective effects and the potential mechanisms of Ganoderma lucidum polysaccharides (GLP) on the degeneration of dopaminergic neurons induced by the neurotoxins methyl-4-phenylpyridine (MPP(+)) and rotenone. Results revealed that GLP can protect dopamine neurons against MPP(+) and rotenone at the concentrations of 100, 50 and 25 μg/ml in primary mesencephalic cultures in a dose-dependent manner. Interestingly, either with or without neurotoxin treatment, GLP treatment elevated the survival of THir neurons, and increased the length of neurites of dopaminergic neurons. The Trolox equivalent anti-oxidant capacity (TEAC) of GLP was determined to be 199.53 μmol Trolox/g extract, and the decrease of mitochondrial complex I activity induced by MPP(+) and rotenone was elevated by GLP treatment (100, 50, 25 and 12.5 μg/ml) in a dose dependent manner. Furthermore, GLP dramatically decreased the relative number of apoptotic cells and increased the declining mitochondrial membrane potential (ΔΨm) induced by MPP(+) and rotenone in a dose-dependent manner. In addition, GLP treatment reduced the ROS formation induced by MPP(+) and rotenone at the concentrations of 100, 50 and 25 μg/ml in a dose-dependent manner. Our study indicates that GLP possesses neuroprotective properties against MPP(+) and rotenone neurotoxicity through suppressing oxidative stress in primary mesencephalic dopaminergic cell culture owning to its antioxidant activities.

  16. Nitro-Oxidative Stress after Neuronal Ischemia Induces Protein Nitrotyrosination and Cell Death

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    Marta Tajes

    2013-01-01

    Full Text Available Ischemic stroke is an acute vascular event that obstructs blood supply to the brain, producing irreversible damage that affects neurons but also glial and brain vessel cells. Immediately after the stroke, the ischemic tissue produces nitric oxide (NO to recover blood perfusion but also produces superoxide anion. These compounds interact, producing peroxynitrite, which irreversibly nitrates protein tyrosines. The present study measured NO production in a human neuroblastoma (SH-SY5Y, a murine glial (BV2, a human endothelial cell line (HUVEC, and in primary cultures of human cerebral myocytes (HC-VSMCs after experimental ischemia in vitro. Neuronal, endothelial, and inducible NO synthase (NOS expression was also studied up to 24 h after ischemia, showing a different time course depending on the NOS type and the cells studied. Finally, we carried out cell viability experiments on SH-SY5Y cells with H2O2, a prooxidant agent, and with a NO donor to mimic ischemic conditions. We found that both compounds were highly toxic when they interacted, producing peroxynitrite. We obtained similar results when all cells were challenged with peroxynitrite. Our data suggest that peroxynitrite induces cell death and is a very harmful agent in brain ischemia.

  17. Intermittent hypoxia hypobaric exposure minimized oxidative stress and antioxidants in brain cells of Sprague Dawleymice

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    Wardaya Wardaya

    2013-05-01

    Full Text Available AbstrakLatar belakang: Hipoksia hypobaric meningkatkan produksi radikal bebas, terutama spesies oksigen reaktif (ROS. Peningkatan ROS akan menyebabkan stres oksidatif bila tidak disertai dengan peningkatan enzim antioksidan. Kondisi ini dapat dikurangi dengan hipoksia hipobarik intermiten (HHI. Tujuan penelitian ini mengidentifikasi frekuensi IHH yang dapat meminimalkan efek hipoksia hipobarik terhadap stres oksidatif dan aktivitas antioksidan spesifik pada tikus Sprague Dawley.Metode: Penelitian eksperimental pada bulan Februari-April 2010, Subjek terdiri dari satu kelompok kontrol dan empat kelompok paparan pada mencit jantan Sprague Dawley. Setiap kelompok terdiri dari 5 tikus. Kelompok kontrol tidak terpapar IHH. Kelompok terpapar (dengan selang waktu satu minggu terpapar sekali, dua kali, tiga kali, atau empat kali IHH. Semua kelompok paparan dipaparkan hipobarik setara dengan ketinggian: 35.000 ft (1 menit, 25.000 ft (5 menit, dan 18.000 ft (25 menit. Jaringan otak diperiksa untuk 8-OHdG dan SOD.Hasil:Setelah tiga paparan IHH tingkat 8-OHdG sudah kembali ke nilai kontrol (P = 0,843. Tingkat SOD meningkat secara progresif pada dua, tiga, dan empat kali paparan IHH. Bahkan setelah paparan kedua, tingkat SOD sudah sama dengan nilai kontrol, 0,231 ± 0,042 (P = 0,191.Kesimpulan: Tiga kali IHH sudah dapat meminimalkan pengaruh hipoksia hipobarik terhadap stres oksidatif dan aktivitas spesifik antioksidan pada tikus Sprague Dawley.Kata kunci: hipoksia hipobarik intermiten, stres oksidatif, antioksidanAbstractBackground: Hypoxia hypobaric increase the production of free radicals, especially reactive oxygen species (ROS. The increase in ROS would cause oxidative stress when not accompanied by an increase in antioxidant enzymes. This condition may minimize by intermittent hypobaric hypoxia (IHH. This study aimed to identify the number of IHH which may minimize the effect of hypoxia hypobaric on oxidative stress and the specific activity of

  18. Aspirin and pravastatin reduce lectin-like oxidized low density lipoprotein receptor-1 expression, adhesion molecules and oxidative stress in human coronary artery endothelial cells

    Institute of Scientific and Technical Information of China (English)

    CHEN Jia-wei; ZHOU Shi-bei; TAN Zhi-ming

    2010-01-01

    Background Oxidative stress and inflammation are important steps in the pathogenesis of atherosclerosis. We postulated that therapeutic concentrations of aspirin and pravastatin, especially in combination, may suppress oxidative stress and inflammation in endothelial cells, and this concept was examined in human coronary artery endothelial cells (HCAECs).Methods Human coronary artery endothelial cells were cultured and treated with oxidized-low density iipoprotein (ox-LDL, 60 μg/ml for 24 hours) alone, or pre-treated with aspirin (1, 2 or 5 mmol/L), pravastatin (1, 5 or 10 μmol/L) or their combination (1 mmol/L aspirin and 5 μmol/L pravastatin), followed by ox-LDL treatment. After respective treatment,superoxide anion production, p38 mitogen activated protein kinase and transcription factor NF-κB activation, protein expression of lectin-like ox-LDL receptor-1 (LOX-1) and adhesion molecules, and monocyte adhesion were measured.Results Ox-LDL treatment greatly elicited its receptor LOX-1 expression, superoxide anion production and inflammatory response, which were minimally affected by low concentration of aspidn (1 mmol/L) or pravastatin (5 μmol/L), but were markedly decreased by their combination. Activation of p38 mitogen activated protein kinase and NF-κB, the expression of intercellular adhesion molecule-1 and monocyte chemotactic protein-1, which were only mildly affected by aspirin or pravastatin alone, were significantly attenuated by their combination. As a consequence, monocyte adhesion to endothelial cells was markedly attenuated by the combination of the two agents. Well-known anti-oxidants α-tocopherol and γ-tocopherol had similar inhibitory effects on ox-LDL-mediated oxidative stress and LOX-1 expression as well as monocyte adhesion as did the combination of aspirin and pravastatin.Conclusions These studies point to a positive interaction between aspidn and pravastatin with regard to endothelial biology. Anti-oxidant and subsequent anti

  19. The effect of oxidative stress in myocardial cell injury in mice exposed to chronic intermittent hypoxia

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-nan; ZHANG Jie-xin; LIU gan; QIU Yan; YANG Di; YIN Guo-yong; ZHANG Xi-long

    2010-01-01

    Background Obstructive sleep apnea syndrome (OSAS) is an important risk factor for cardiovascular diseases. Chronic intermittent hypoxia (CIH) is considered to be one of the most important causes of cardiovascular diseases in OSA patients. This repeated hypoxia and reoxygenation cycle is similar to hypoxia-reperfusion injury, which initiates oxidative stress. In this study, we observed cardiocytes injury induced by CIH and the effect of N-acetylcysteine (NAC). Methods Thirty ICR mice were randomly assigned to 3 groups: control, CIH and NAC (CIH+NAC) groups. Malondialdehyde (MDA) and superoxide dismutase (SOD) of cardiocyte homogenates were measured. Serum lipids were measured by an instrument method. Serum cardiac troponin I (cTnl) was detected by enzyme-linked immunosorbent assays (ELISA). Myocardium pathological sections were observed.Results (1) The SOD activity and MDA concentration of cardiocyte homogenates in the CIH group were significantly higher than in other groups (P <0.005). The MDA concentration of the NAC group was lower than that of the control group (P <0.01). (2) The serum cTnl concentration of the CIH and NAC groups was significantly higher than that of the control group (P<0.01). (3) Serum triglyceride levels in the NAC group were lower than in the other groups (P<0.01), while there were no significant differences in low density lipoprotein and high density lipoprotein among the three groups. (4) The degeneration of myocardium, transverse striation blurred, and fabric effusion were observed in tissue sections in the CIH and NAC groups. However, normal tissue was found in the control group.Conclusion The oxidative stress induced by CIH can injure cardiocytes and the injury effect can be partially inhibited by NAC.

  20. The pro-oxidant gene p66shc increases nicotine exposure-induced lipotoxic oxidative stress in renal proximal tubule cells.

    Science.gov (United States)

    Arany, Istvan; Hall, Samuel; Reed, Dustin K; Dixit, Mehul

    2016-09-01

    Nicotine (NIC) exposure augments free fatty acid (FFA) deposition and oxidative stress, with a concomitant increase in the expression of the pro-oxidant p66shc. In addition, a decrease in the antioxidant manganese superoxide dismutase (MnSOD) has been observed in the kidneys of mice fed a high‑fat diet. The present study aimed to determine whether the pro‑oxidant p66shc mediates NIC‑dependent increases in renal oxidative stress by augmenting the production of reactive oxygen species (ROS) and suppressing the FFA‑induced antioxidant response in cultured NRK52E renal proximal tubule cells. Briefly, NRK52E renal proximal tubule cells were treated with 200 µM NIC, 100 µM oleic acid (OA), or a combination of NIC and OA. The expression levels of p66shc and MnSOD were modulated according to genetic methods. ROS production and cell injury, in the form of lactate dehydrogenase release, were subsequently detected. Promoter activity of p66shc and MnSOD, as well as forkhead box (FOXO)‑dependent transcription, was investigated using reporter luciferase assays. The results demonstrated that NIC exacerbated OA‑mediated intracellular ROS production and cell injury through the transcriptional activation of p66shc. NIC also suppressed OA‑mediated induction of the antioxidant MnSOD promoter activity through p66shc‑dependent inactivation of FOXO activity. Overexpression of p66shc and knockdown of MnSOD had the same effect as treatment with NIC on OA‑mediated lipotoxicity. These data may be used to generate a therapeutic means to ameliorate renal lipotoxicity in obese smokers.

  1. Effect of stress on NiO reduction in solid oxide fuel cells: A new application of energy-resolved neutron imaging

    DEFF Research Database (Denmark)

    Makowska, Malgorzata; Strobl, Markus; Lauridsen, Erik Mejdal

    2015-01-01

    Recently, two new phenomena linking stress field and reduction rates in anode-supported solid oxide fuel cells (SOFCs) have been demonstrated, so-called accelerated creep during reduction and reduction rate enhancement and nucleation due to stress (Frandsen et al., 2014). These complex phenomena ...

  2. Schwann Cell-Mediated Preservation of Vision in Retinal Degenerative Diseases via the Reduction of Oxidative Stress: A Possible Mechanism

    Science.gov (United States)

    MAHMOUDZADEH, Raziyeh; HEIDARI-KESHEL, Saeed; LASHAY, Alireza

    2016-01-01

    After injury to the central nervous system (CNS), regeneration is often inadequate, except in the case of remyelination. This remyelination capacity of the CNS is a good example of a stem/precursor cell-mediated renewal process. Schwann cells have been found to act as remyelinating agents in the peripheral nervous system (PNS), but several studies have highlighted their potential role in remyelination in the CNS too. Schwann cells are able to protect and support retinal cells by secreting growth factors such as brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and basic fibroblast growth factor. Retinal degenerative diseases can be highly debilitating, and they are a major concern in countries with an ageing populations. One of the leading causes of permanent loss of vision in the West is a retinal degenerative disease known as age-related macular degeneration (AMD). In the United States, nearly 1.75 million people over the age of 40 have advanced AMD, and it is estimated that this number will increase to approximately 3 million people by 2020. One of the most common pathways involved in the initiation and development of retinal diseases is the oxidative stress pathway. In patients with diabetes, Schwann cells have been shown to be able to secrete large amounts of antioxidant enzymes that protect the PNS from the oxidative stress that results from fluctuations in blood glucose levels. This antioxidant ability may be involved in the mechanism by which Schwann cells are able to promote reconstruction in the CNS, especially in individuals with retinal injuries and degenerative diseases. PMID:28293647

  3. Organophosphorus insecticides chlorpyrifos and diazinon and oxidative stress in neuronal cells in a genetic model of glutathione deficiency.

    Science.gov (United States)

    Giordano, Gennaro; Afsharinejad, Zhara; Guizzetti, Marina; Vitalone, Annabella; Kavanagh, Terrance J; Costa, Lucio G

    2007-03-01

    Over the past several years evidence has been accumulating from in vivo animal studies, observations in humans, and in vitro studies, that organophosphorus (OP) insecticides may induce oxidative stress. Such effects may contribute to some of the toxic manifestations of OPs, particularly upon chronic or developmental exposures. The aim of this study was to investigate the role of oxidative stress in the neurotoxicity of two commonly used OPs, chlorpyrifos (CPF) and diazinon (DZ), their oxygen analogs (CPO and DZO), and their "inactive" metabolites (TCP and IMP), in neuronal cells from a genetic model of glutathione deficiency. Cerebellar granule neurons from wild type mice (Gclm +/+) and mice lacking the modifier subunit of glutamate cysteine ligase (Gclm -/-), the first and limiting step in the synthesis of glutathione (GSH), were utilized. The latter display very low levels of GSH and are more susceptible to the toxicity of agents that increase oxidative stress. CPO and DZO were the most cytotoxic compounds, followed by CPF and DZ, while TCP and IMP displayed lower toxicity. Toxicity was significantly higher (10- to 25-fold) in neurons from Gclm (-/-) mice, and was antagonized by various antioxidants. Depletion of GSH from Gclm (+/+) neurons significantly increased their sensitivity to OP toxicity. OPs increased intracellular levels of reactive oxygen species and lipid peroxidation and in both cases the effects were greater in neurons from Gclm (-/-) mice. OPs did not alter intracellular levels of GSH, but significantly increased those of oxidized glutathione (GSSG). Cytotoxicity was not antagonized by cholinergic antagonists, but was decreased by the calcium chelator BAPTA-AM. These studies indicate that cytotoxicity of OPs involves generation of reactive oxygen species and is modulated by intracellular GSH, and suggest that it may involve disturbances in intracellular homeostasis of calcium.

  4. Oxidative Stress in Cystinosis Patients

    Directory of Open Access Journals (Sweden)

    Maria Helena Vaisbich

    2011-09-01

    Full Text Available Background/Aims: Nephropathic cystinosis (NC is a severe systemic disease and cysteamine improves its prognosis. Lysosomal cystine accumulation is the hallmark of cystinosis and is regarded as the primary defect due to mutations in the CTNS gene. However, there is great evidence that cystine accumulation itself is not responsible for all abnormalities observed in NC. Studies have demonstrated altered ATP metabolism, increased apoptosis, and cell oxidation. An increased number of autophagosomes and autophagic vacuoles have been observed in cystinotic fibroblasts and renal epithelial cells, suggesting that altered autophagy plays a role in NC, leading to increased production of reactive oxygen species. Therefore, cystinosis patients can be more susceptible to oxidative stress (OS and it can contribute to the progression of the renal disease. Our goal was to evaluate a marker of OS (serum TBARS in NC children, and to compare the results with those observed in healthy controls and correlated with renal function parameters. Methods: The study included patients aged under 18 years, with good adherence to the treatment and out of renal replacement therapy. The following parameters were evaluated: serum creatinine, BUN, creatinine clearance estimated by stature and serum TBARS levels. Results: We selected 20 patients aged 8.0 ±3.6 years and observed serum TBARS levels of 4.03 ±1.02 nmol/ml. Serum TBARS levels in the 43 healthy controls, aged 7.4 ±1.1 years, were 1.60 ±0.04 nmol/ml. There was a significant difference between the plasma TBARS levels among the 2 groups (p Conclusion: An increased level of serum TBARS in patients with NC was observed and this abnormality was not correlated with the renal function status degree. This is the first report that shows increased oxidative stress in serum of NC patients.

  5. Mechanisms of Multi-walled Carbon Nanotubes-Induced Oxidative Stress and Genotoxicity in Mouse Fibroblast Cells.

    Science.gov (United States)

    Alarifi, Saud; Ali, Daoud

    2015-01-01

    The extensive production and wide application of carbon nanotubes have made investigations of its toxic potentials necessary. In the present study, we explored the underlying mechanism through which multi-walled carbon nanotubes (MWCNTs) induce toxicity in mouse fibroblast cells (L929). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and neutral red uptake viability assays were used to examine mechanisms of cytotoxicity. Dose and time-dependent cytotoxicity was observed in L929 cells. The MWCNTs significantly increased the generation of reactive oxygen species, lipid peroxidation, superoxide dismutase, and decreased glutathione. It was observed that the MWCNTs induced caspase 3 activity. The highest DNA strand breakage was detected by comet assay at 300 µg/mL of MWCNTs. Thus, the data indicate that MWCNTs induced cytotoxicity and apoptosis in L929 cells via oxidative stress.

  6. Oxidative stress and the ageing endocrine system.

    Science.gov (United States)

    Vitale, Giovanni; Salvioli, Stefano; Franceschi, Claudio

    2013-04-01

    Ageing is a process characterized by a progressive decline in cellular function, organismal fitness and increased risk of age-related diseases and death. Several hundred theories have attempted to explain this phenomenon. One of the most popular is the 'oxidative stress theory', originally termed the 'free radical theory'. The endocrine system seems to have a role in the modulation of oxidative stress; however, much less is known about the role that oxidative stress might have in the ageing of the endocrine system and the induction of age-related endocrine diseases. This Review outlines the interactions between hormones and oxidative metabolism and the potential effects of oxidative stress on ageing of endocrine organs. Many different mechanisms that link oxidative stress and ageing are discussed, all of which converge on the induction or regulation of inflammation. All these mechanisms, including cell senescence, mitochondrial dysfunction and microRNA dysregulation, as well as inflammation itself, could be targets of future studies aimed at clarifying the effects of oxidative stress on ageing of endocrine glands.

  7. Cell signaling and receptors in toxicity of advanced glycation end products (AGEs): α-dicarbonyls, radicals, oxidative stress and antioxidants.

    Science.gov (United States)

    Kovacic, Peter; Somanathan, Ratnasamy

    2011-10-01

    Considerable attention has been paid to the toxicity of advanced glycation end products (AGEs), including relation to various illnesses. AGEs, generated nonenzymatically from carbohydrates and proteins, comprises large numbers of simple and more complicated compounds. Many reports deal with a role for receptors (RAGE) and cell signaling, including illnesses and aging. Reactive oxygen species appear to participate in signaling. RAGE include angiotensin II type 1 receptors. Many signaling pathways are involved, such as kinases, p38, p21, TGF-β, NF-κβ, TNF-α, JNK and STAT. A recent review puts focus on α-dicarbonyl metabolites, formed by carbohydrate oxidation, and imine derivatives from protein condensation, as a source via electron transfer (ET) of ROS and oxidative stress (OS). The toxic species have been related to illnesses and aging. Antioxidants alleviate the adverse effects.

  8. Protective Effects of PGC-1α Against Lead-Induced Oxidative Stress and Energy Metabolism Dysfunction in Testis Sertoli Cells.

    Science.gov (United States)

    Liu, Xi; Ye, Jingping; Wang, Lu; Li, Zhen; Zhang, Yucheng; Sun, Jiantao; Du, Chuang; Wang, Chunhong; Xu, Siyuan

    2017-02-01

    The reproductive system is sensitive to lead (Pb) toxicity, which has long been an area of research interest, but the underlying mechanisms remain to be illustrated. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is pivotal in mitochondrial function. In this study, mouse testis Sertoli cells (TM4 cells), PGC-1α lower-expression (PGC-1α(-)) TM4 cells and PGC-1α overexpression (PGC-1α(+)) TM4 cells were used to explore the protective roles of PGC-1α against lead toxicity on the mouse reproductive system. Lead acetate (PbAc) exposure decreased the expression level of PGC-1α, increased the intracellular level of reactive oxygen species (ROS), and reduced the level of ATP in the three TM4 cell lines. The effects of PbAc on intracellular ATP level and on ROS content were significantly weakened in PGC-1α(+)TM4 cells versus TM4 cells and were significantly amplified in PGC-1α(-)TM4 cells versus TM4 cells. These results suggest that PGC-1α is a protective factor against PbAc-induced oxidative stress and energy metabolism dysfunction in the mouse reproductive system, thereby holding the potential of being developed as a preventive or therapeutic strategy against disorders induced by lead exposure.

  9. Oxidative stress induces monocyte necrosis with enrichment of cell-bound albumin and overexpression of endoplasmic reticulum and mitochondrial chaperones.

    Directory of Open Access Journals (Sweden)

    Haiping Tang

    Full Text Available In the present study, monocytes were treated with 5-azacytidine (azacytidine, gossypol or hydrogen peroxide to induce cell death through oxidative stress. A shift from apoptotic to necrotic cell death occurred when monocytes were treated with 100 µM azacytidine for more than 12 hours. Necrotic monocytes exhibited characteristics, including enrichment of cell-bound albumin and up-regulation of endoplasmic reticulum (ER- and mitochondrial-specific chaperones to protect mitochondrial integrity, which were not observed in other necrotic cells, including HUH-7, A2780, A549 and HOC1a. Our results show that the cell-bound albumin originates in the culture medium rather than from monocyte-derived hepatocytes, and that HSP60 is a potential binding partner of the cell-bound albumin. Proteomic analysis shows that HSP60 and protein disulfide isomerase are the most abundant up-regulated mitochondrial and ER-chaperones, and that both HSP60 and calreticulin are ubiquitinated in necrotic monocytes. In contrast, expression levels of the cytosolic chaperones HSP90 and HSP71 were down-regulated in the azacytidine-treated monocytes, concomitant with an increase in the levels of these chaperones in the cell culture medium. Collectively, our results demonstrates that chaperones from different organelles behave differently in necrotic monocytes, ER- and mitochondrial chaperones being retained and cytosolic and nuclear chaperones being released into the cell culture medium through the ruptured cell membrane. HSP60 may serve as a new target for development of myeloid leukemia treatment.

  10. Hydrodynamic stress induces monoterpenoid oxindole alkaloid accumulation by Uncaria tomentosa (Willd) D. C. cell suspension cultures via oxidative burst.

    Science.gov (United States)

    Trejo-Tapia, Gabriela; Sepúlveda-Jiménez, Gabriela; Trejo-Espino, José Luis; Cerda-García-Rojas, Carlos M; de la Torre, Mayra; Rodríguez-Monroy, Mario; Ramos-Valdivia, Ana C

    2007-09-01

    Uncaria tomentosa cell suspension cultures were grown in a 2-L stirred tank bioreactor operating at a shear rate gamma(.)(avg)=86 s(-1). The cultures showed an early monophasic oxidative burst measured as H2O2 production (2.15 micromol H2O2 g(-1) dw). This response was followed by a transient production of monoterpenoid oxindole alkaloids (178 +/- 40 microg L(-1) at 24 h). At the stationary phase (144 h), the increase of the shear rate gamma(.)(avg) up to 150 s(-1) and/or oxygen tension up to 85% generated H2O2, restoring oxindole alkaloid production. U. tomentosa cells cultured in Erlenmeyer flasks also exhibited the monophasic oxidative burst but the H2O2 production was 16-fold lower and the alkaloids were not detected. These cells exposed to H2O2 generated in situ produced oxindole alkaloids reaching a maximum of 234 +/- 40 microg L(-1). A positive correlation was observed between the oxindole alkaloid production and the endogenous H2O2 level. On the other hand, addition of 1 microM diphenyleneiodonium (NAD(P)H oxidase inhibitor) or 10 microM sodium azide (peroxidases inhibitor) reduced both H2O2 production and oxindole alkaloids build up, suggesting that these enzymes might play a role in the oxidative burst induced by the hydrodynamic stress.

  11. Macrophage Interaction with Paracoccidioides brasiliensis Yeast Cells Modulates Fungal Metabolism and Generates a Response to Oxidative Stress

    Science.gov (United States)

    Parente-Rocha, Juliana Alves; Parente, Ana Flávia Alves; Baeza, Lilian Cristiane; Bonfim, Sheyla Maria Rondon Caixeta; Hernandez, Orville; McEwen, Juan G.; Bailão, Alexandre Melo; Taborda, Carlos Pelleschi; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

    2015-01-01

    Macrophages are key players during Paracoccidioides brasiliensis infection. However, the relative contribution of the fungal response to counteracting macrophage activity remains poorly understood. In this work, we evaluated the P. brasiliensis proteomic response to macrophage internalization. A total of 308 differentially expressed proteins were detected in P. brasiliensis during infection. The positively regulated proteins included those involved in alternative carbon metabolism, such as enzymes involved in gluconeogenesis, beta-oxidation of fatty acids and amino acids catabolism. The down-regulated proteins during P. brasiliensis internalization in macrophages included those related to glycolysis and protein synthesis. Proteins involved in the oxidative stress response in P. brasiliensis yeast cells were also up-regulated during macrophage infection, including superoxide dismutases (SOD), thioredoxins (THX) and cytochrome c peroxidase (CCP). Antisense knockdown mutants evaluated the importance of CCP during macrophage infection. The results suggested that CCP is involved in a complex system of protection against oxidative stress and that gene silencing of this component of the antioxidant system diminished the survival of P. brasiliensis in macrophages and in a murine model of infection. PMID:26360774

  12. Eriodictyol Protects Endothelial Cells against Oxidative Stress-Induced Cell Death through Modulating ERK/Nrf2/ARE-Dependent Heme Oxygenase-1 Expression

    Directory of Open Access Journals (Sweden)

    Seung Eun Lee

    2015-06-01

    Full Text Available The pathophysiology of cardiovascular diseases is complex and may involve oxidative stress-related pathways. Eriodictyol is a flavonoid present in citrus fruits that demonstrates anti-inflammatory, anti-cancer, neurotrophic, and antioxidant effects in a range of pathophysiological conditions including vascular diseases. Because oxidative stress plays a key role in the pathogenesis of cardiovascular disease, the present study was designed to verify whether eriodictyol has therapeutic potential. Upregulation of heme oxygenase-1 (HO-1, a phase II detoxifying enzyme, in endothelial cells is considered to be helpful in cardiovascular disease. In this study, human umbilical vein endothelial cells (HUVECs treated with eriodictyol showed the upregulation of HO-1 through extracellular-regulated kinase (ERK/nuclear factor erythroid 2-related factor 2 (Nrf2/antioxidant response element (ARE signaling pathways. Further, eriodictyol treatment provided protection against hydrogen peroxide-provoked cell death. This protective effect was eliminated by treatment with a specific inhibitor of HO-1 and RNA interference-mediated knockdown of HO-1 expression. These data demonstrate that eriodictyol induces ERK/Nrf2/ARE-mediated HO-1 upregulation in human endothelial cells, which is directly associated with its vascular protection against oxidative stress-related endothelial injury, and propose that targeting the upregulation of HO-1 is a promising approach for therapeutic intervention in cardiovascular disease.

  13. Oxidative Stress and Nano-Toxicity Induced by TiO2 and ZnO on WAG Cell Line.

    Directory of Open Access Journals (Sweden)

    Akhilesh Dubey

    Full Text Available Metallic nanoparticles are widely used in cosmetics, food products and textile industry. These particles are known to cause respiratory toxicity and epithelial inflammation. They are eventually released to aquatic environment necessitating toxicity studies in cells from respiratory organs of aquatic organisms. Hence, we have developed and characterized a new cell line, WAG, from gill tissue of Wallago attu for toxicity assessment of TiO2 and ZnO nanoparticles. The efficacy of the cell line as an in vitro system for nanoparticles toxicity studies was established using electron microscopy, cytotoxicity assays, genotoxicity assays and oxidative stress biomarkers. Results obtained with MTT assay, neutral red uptake assay and lactate dehydrogenase assay showed acute toxicity to WAG cells with IC50 values of 25.29 ± 0.12, 34.99 ± 0.09 and 35.06 ± 0.09 mg/l for TiO2 and 5.716 ± 0.1, 3.160 ± 0.1 and 5.57 ± 0.12 mg/l for ZnO treatment respectively. The physicochemical properties and size distribution of nanoparticles were characterized using electron microscopy with integrated energy dispersive X-ray spectroscopy and Zetasizer. Dose dependent increase in DNA damage, lipid peroxidation and protein carbonylation along with a significant decrease in activity of Superoxide Dismutase, Catalase, total Glutathione levels and total antioxidant capacity with increasing concentration of exposed nanoparticles indicated that the cells were under oxidative stress. The study established WAG cell line as an in vitro system to study toxicity mechanisms of nanoparticles on aquatic organisms.

  14. The oxidative stress responsive transcription factor Pap1 confers DNA damage resistance on checkpoint-deficient fission yeast cells.

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    Carrie Belfield

    Full Text Available Eukaryotic cells invoke mechanisms to promote survival when confronted with cellular stress or damage to the genome. The protein kinase Chk1 is an integral and conserved component of the DNA damage response pathway. Mutation or inhibition of Chk1 results in mitotic death when cells are exposed to DNA damage. Oxidative stress activates a pathway that results in nuclear accumulation of the bZIP transcription factor Pap1. We report the novel finding that fission yeast Pap1 confers resistance to drug- and non-drug-induced DNA damage even when the DNA damage checkpoint is compromised. Multi-copy expression of Pap1 restores growth to chk1-deficient cells exposed to camptothecin or hydroxyurea. Unexpectedly, increased Pap1 expression also promotes survival of chk1-deficient cells with mutations in genes encoding DNA ligase (cdc17 or DNA polymerase δ (cdc6, but not DNA replication initiation mutants. The ability of Pap1 to confer resistance to DNA damage was not specific to chk1 mutants, as it also improved survival of rad1- and rad9-deficient cells in the presence of CPT. To confer resistance to DNA damage Pap1 must localize to the nucleus and be transcriptionally active.

  15. Interdependence of tetrapyrrole metabolism, the generation of oxidative stress and the mitigative oxidative stress response

    Directory of Open Access Journals (Sweden)

    Andrea W.U. Busch

    2015-04-01

    Full Text Available Tetrapyrroles are involved in light harvesting and light perception, electron-transfer reactions, and as co-factors for key enzymes and sensory proteins. Under conditions in which cells exhibit stress-induced imbalances of photosynthetic reactions, or light absorption exceeds the ability of the cell to use photoexcitation energy in synthesis reactions, redox imbalance can occur in photosynthetic cells. Such conditions can lead to the generation of reactive oxygen species (ROS associated with alterations in tetrapyrrole homeostasis. ROS accumulation can result in cellular damage and detrimental effects on organismal fitness, or ROS molecules can serve as signals to induce a protective or damage-mitigating oxidative stress signaling response in cells. Induced oxidative stress responses include tetrapyrrole-dependent and -independent mechanisms for mitigating ROS generation and/or accumulation. Thus, tetrapyrroles can be contributors to oxidative stress, but are also essential in the oxidative stress response to protect cells by contributing to detoxification of ROS. In this review, we highlight the interconnection and interdependence of tetrapyrrole metabolism with the occurrence of oxidative stress and protective oxidative stress signaling responses in photosynthetic organisms.

  16. Inhibition of cell proliferation and migration by oxidative stress from ascorbate-driven juglone redox cycling in human bladder-derived T24 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kviecinski, M.R., E-mail: mrkviecinski@hotmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Pedrosa, R.C., E-mail: rozangelapedrosa@gmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Felipe, K.B., E-mail: kakabettega@yahoo.com.br [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Farias, M.S., E-mail: mirellesfarias@hotmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Glorieux, C., E-mail: christophe.glorieux@uclouvain.be [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); Valenzuela, M., E-mail: mavalenzuela@med.uchile.cl [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); Sid, B., E-mail: brice.sid@uclouvain.be [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); and others

    2012-05-04

    Highlights: Black-Right-Pointing-Pointer The cytotoxicity of juglone is markedly increased by ascorbate. Black-Right-Pointing-Pointer T24 cell death by oxidative stress is necrosis-like. Black-Right-Pointing-Pointer Redox cycling by juglone/ascorbate inhibits cell proliferation. Black-Right-Pointing-Pointer Cellular migration is impaired by juglone/ascorbate. -- Abstract: The effects of juglone on T24 cells were assessed in the presence and absence of ascorbate. The EC{sub 50} value for juglone at 24 h decreased from 28.5 {mu}M to 6.3 {mu}M in the presence of ascorbate. In juglone-treated cells, ascorbate increased ROS formation (4-fold) and depleted GSH (65%). N-acetylcysteine or catalase restricted the juglone/ascorbate-mediated effects, highlighting the role of oxidative stress in juglone cytotoxicity. Juglone alone or associated with ascorbate did not cause caspase-3 activation or PARP cleavage, suggesting necrosis-like cell death. DNA damage and the mild ER stress caused by juglone were both enhanced by ascorbate. In cells treated with juglone (1-5 {mu}M), a concentration-dependent decrease in cell proliferation was observed. Ascorbate did not impair cell proliferation but its association with juglone led to a clonogenic death state. The motility of ascorbate-treated cells was not affected. Juglone slightly restricted motility, but cells lost their ability to migrate most noticeably when treated with juglone plus ascorbate. We postulate that juglone kills cells by a necrosis-like mechanism inhibiting cell proliferation and the motility of T24 cells. These effects are enhanced in the presence of ascorbate.

  17. Extracts from Calendula officinalis offer in vitro protection against H2 O2 induced oxidative stress cell killing of human skin cells.

    Science.gov (United States)

    Alnuqaydan, Abdullah M; Lenehan, Claire E; Hughes, Rachel R; Sanderson, Barbara J

    2015-01-01

    The in vitro safety and antioxidant potential of Calendula officinalis flower head extracts was investigated. The effect of different concentrations (0.125, 0.5, 1.0, 2.0 and 5.0% (v/v)) of Calendula extracts on human skin cells HaCaT in vitro was explored. Doses of 1.0% (v/v) (0.88 mg dry weight/mL) or less showed no toxicity. Cells were also exposed to the Calendula extracts for either 4, 24 or 48 h before being exposed to an oxidative insult (hydrogen peroxide H2 O2 ) for 1 h. Using the MTT cytotoxicity assay, it was observed that two independent extracts of C. officinalis gave time-dependent and concentration-dependent H2 O2 protection against induced oxidative stress in vitro using human skin cells. Pre-incubation with the Calendula extracts for 24 and 48 h increased survival relative to the population without extract by 20% and 40% respectively following oxidative challenge. The antioxidant potential of the Calendula extracts was confirmed using a complimentary chemical technique, the DPPH(●) assay. Calendula extracts exhibited free radical scavenging abilities. This study demonstrates that Calendula flower extracts contain bioactive and free radical scavenging compounds that significantly protect against oxidative stress in a human skin cell culture model.

  18. Kallikrein transduced mesenchymal stem cells protect against anti-GBM disease and lupus nephritis by ameliorating inflammation and oxidative stress.

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    Yajuan Li

    Full Text Available Previously we have shown that kallikreins (klks play a renoprotective role in nephrotoxic serum induced nephritis. In this study, we have used mesenchymal stem cells (MSCs as vehicles to deliver klks into the injured kidneys and have measured their therapeutic effect on experimental antibody induced nephritis and lupus nephritis. Human KLK-1 (hKLK1 gene was transduced into murine MSCs using a retroviral vector to generate a stable cell line, hKLK1-MSC, expressing high levels of hKLK1. 129/svj mice subjected to anti-GBM induced nephritis were transplanted with 10(6 hKLK1-MSCs and hKLK1 expression was confirmed in the kidneys. Compared with vector-MSCs injected mice, the hKLK1-MSCs treated mice showed significantly reduced proteinuria, blood urea nitrogen (BUN and ameliorated renal pathology. Using the same strategy, we treated lupus-prone B6.Sle1.Sle3 bicongenic mice with hKLK1-MSCs and demonstrated that hKLK1-MSCs delivery also attenuated lupus nephritis. Mechanistically, hKLK1-MSCs reduced macrophage and T-lymphocyte infiltration into the kidney by suppressing the expression of inflammation cytokines. Moreover, hKLK1 transduced MSCs were more resistant to oxidative stress-induced apoptosis. These findings advance genetically modified MSCs as potential gene delivery tools for targeting therapeutic agents to the kidneys in order to modulate inflammation and oxidative stress in lupus nephritis.

  19. MitoTEMPO Prevents Oxalate Induced Injury in NRK-52E Cells via Inhibiting Mitochondrial Dysfunction and Modulating Oxidative Stress

    Science.gov (United States)

    Yu, Xiao; Liu, Jihong

    2017-01-01

    As one of the major risks for urolithiasis, hyperoxaluria can be caused by genetic defect or dietary intake. And high oxalate induced renal epithelial cells injury is related to oxidative stress and mitochondrial dysfunction. Here, we investigated whether MitoTEMPO, a mitochondria-targeted antioxidant, could protect against oxalate mediated injury in NRK-52E cells via inhibiting mitochondrial dysfunction and modulating oxidative stress. MitoSOX Red was used to determine mitochondrial ROS (mtROS) production. Mitochondrial membrane potential (Δψm) and quantification of ATP synthesis were measured to evaluate mitochondrial function. The protein expression of Nox4, Nox2, and p22 was also detected to explore the effect of oxalate and MitoTEMPO on NADPH oxidase. Our results revealed that pretreatment with MitoTEMPO significantly inhibited oxalate induced lactate dehydrogenase (LDH) and malondialdehyde (MDA) release and decreased oxalate induced mtROS generation. Further, MitoTEMPO pretreatment restored disruption of Δψm and decreased ATP synthesis mediated by oxalate. In addition, MitoTEMPO altered the protein expression of Nox4 and p22 and decreased the protein expression of IL-6 and osteopontin (OPN) induced by oxalate. We concluded that MitoTEMPO may be a new candidate to protect against oxalate induced kidney injury as well as urolithiasis.

  20. Blood-Brain Barrier Disruption and Oxidative Stress in Guinea Pig after Systemic Exposure to Modified Cell-Free Hemoglobin

    Science.gov (United States)

    Butt, Omer I.; Buehler, Paul W.; D'Agnillo, Felice

    2011-01-01

    Systemic exposure to cell-free hemoglobin (Hb) or its breakdown products after hemolysis or with the use of Hb-based oxygen therapeutics may alter the function and integrity of the blood-brain barrier. Using a guinea pig exchange transfusion model, we investigated the effect of a polymerized cell-free Hb (HbG) on the expression of endothelial tight junction proteins (zonula occludens 1, claudin-5, and occludin), astrocyte activation, IgG extravasation, heme oxygenase (HO), iron deposition, oxidative end products (4-hydroxynonenal adducts and 8-hydroxydeoxyguanosine), and apoptosis (cleaved caspase 3). Reduced zonula occludens 1 expression was observed after HbG transfusion as evidenced by Western blot and confocal microscopy. Claudin-5 distribution was altered in small- to medium-sized vessels. However, total expression of claudin-5 and occludin remained unchanged except for a notable increase in occludin 72 hours after HbG transfusion. HbG-transfused animals also showed increased astrocytic glial fibrillary acidic protein expression and IgG extravasation after 72 hours. Increased HO activity and HO-1 expression with prominent enhancement of HO-1 immunoreactivity in CD163-expressing perivascular cells and infiltrating monocytes/macrophages were also observed. Consistent with oxidative stress, HbG increased iron deposition, 4-hydroxynonenal and 8-hydroxydeoxyguanosine immunoreactivity, and cleaved caspase-3 expression. Systemic exposure to an extracellular Hb triggers blood-brain barrier disruption and oxidative stress, which may have important implications for the use of Hb-based therapeutics and may provide indirect insight on the central nervous system vasculopathies associated with excessive hemolysis. PMID:21356382

  1. Increased oxidative stress and cytotoxicity by hydrogen sulfide in HepG2 cells overexpressing cytochrome P450 2E1.

    Science.gov (United States)

    Caro, Andres A; Thompson, Sarah; Tackett, Jonathan

    2011-12-01

    The main objectives of this work were to evaluate the effects of hydrogen sulfide on oxidative stress and cytotoxicity parameters in HepG2 cells and to assess the extent to which cytochrome P450 2E1 (CYP2E1) activity modulates the effects of hydrogen sulfide on oxidative stress and cytotoxicity. Sodium hydrosulfide (NaHS) caused time- and concentration-dependent cytotoxicity in both non-P450-expressing HepG2 cells (C34 cells) and CYP2E1-overexpressing HepG2 cells (E47 cells); however, NaHS-dependent cytotoxicity was higher in E47 than C34 cells. Cytotoxicity by NaHS in C34 and E47 cells was mainly necrotic in nature and associated with an early decrease in mitochondrial membrane potential. NaHS caused increased oxidation of lipophilic (C11-BODIPY(581/591)) and hydrophilic (DCFH-DA) probes only in E47 cells, at a time point prior to overt cytotoxicity. Trolox, an amphipathic antioxidant, partially inhibited both the cytotoxicity and the increased oxidative stress detected in E47 cells exposed to NaHS. Cell-permeable iron chelators and CYP2E1 inhibitors significantly inhibited the oxidation of C11-BODIPY(581/591) in E47 cells in the presence of NaHS. NaHS produced lipid peroxidation and cytotoxicity in E47 cells supplemented with a representative polyunsaturated fatty acid (docosahexaenoic acid) but not in C34 cells; these effects were inhibited by α-tocopherol, a lipophilic antioxidant. These data suggest that CYP2E1 enhances H(2)S-dependent cytotoxicity in HepG2 cells through the generation of iron-dependent oxidative stress and lipid peroxidation.

  2. Role of CFTR in oxidative stress and suicidal death of renal cells during cisplatin-induced nephrotoxicity.

    Science.gov (United States)

    Rubera, I; Duranton, C; Melis, N; Cougnon, M; Mograbi, B; Tauc, M

    2013-10-03

    The clinical use of the antineoplastic drug cisplatin is limited by its deleterious nephrotoxic side effect. Cisplatin-induced nephrotoxicity is associated with an increase in oxidative stress, leading ultimately to renal cell death and irreversible kidney dysfunction. Oxidative stress could be modified by the cystic fibrosis transmembrane conductance regulator protein (CFTR), a Cl(-) channel not only involved in chloride secretion but as well in glutathione (GSH) transport. Thus, we tested whether the inhibition of CFTR could protect against cisplatin-induced nephrotoxicity. Using a renal proximal cell line, we show that the specific inhibitor of CFTR, CFTR(inh)-172, prevents cisplatin-induced cell death and apoptosis by modulating the intracellular reactive oxygen species balance and the intracellular GSH concentration. This CFTR(inh)-172-mediated protective effect occurs without affecting cellular cisplatin uptake or the formation of platinum-DNA adducts. The protective effect of CFTR(inh)-172 in cisplatin-induced nephrotoxicity was also investigated in a rat model. Five days after receiving a single cisplatin injection (5 mg/kg), rats exhibited renal failure, as evidenced by the alteration of biochemical and functional parameters. Pretreatment of rats with CFTR(inh)-172 (1 mg/kg) prior to cisplatin injection significantly prevented these deleterious cisplatin-induced nephrotoxic effects. Finally, we demonstrate that CFTR(inh)-172 does not impair cisplatin-induced cell death in the cisplatin-sensitive A549 cancer cell line. In conclusion, the use of a specific inhibitor of CFTR may represent a novel therapeutic approach in the prevention of nephrotoxic side effects during cisplatin treatment without affecting its antitumor efficacy.

  3. Effects of Lead and Cadmium on Brain Endothelial Cell Survival, Monolayer Permeability, and Crucial Oxidative Stress Markers in an in Vitro Model of the Blood-Brain Barrier

    Directory of Open Access Journals (Sweden)

    Shakila Tobwala

    2014-06-01

    Full Text Available Oxidative stress, which is the loss of balance between antioxidant defense and oxidant production in the cells, is implicated in the molecular mechanism of heavy metal-induced neurotoxicity. Given the key role of lead (Pb and cadmium (Cd in inducing oxidative stress, we investigated their role in disrupting the integrity and function of immortalized human brain microvascular endothelial cells (hCMEC/D3. To study this, hCMEC/D3 cells were exposed to control media or to media containing different concentrations of Pb or Cd. Those exposed to Pb or Cd showed significantly higher oxidative stress than the untreated group, as indicated by cell viability, reactive oxygen species (ROS, glutathione (GSH levels, and catalase enzyme activity. Pb also induced oxidative stress-related disruption of the hCMEC/D3 cell monolayer, as measured by trans-endothelial electrical resistance (TEER, the dextran permeability assay, and the level of tight junction protein, zona occluden protein (ZO-2. However, no significant disruption in the integrity of the endothelial monolayer was seen with cadmium at the concentrations used. Taken together, these results show that Pb and Cd induce cell death and dysfunction in hCMEC/D3 cells and, in the case of Pb, barrier disruption. This suggests blood brain barrier (BBB dysfunction as a contributing mechanism in Pb and Cd neurotoxicities.

  4. Biodecolorization of azo dye Remazol orange by Pseudomonas aeruginosa BCH and toxicity (oxidative stress) reduction in Allium cepa root cells.

    Science.gov (United States)

    Jadhav, Shekhar B; Surwase, Shripad N; Kalyani, Dayanand C; Gurav, Ranjit G; Jadhav, Jyoti P

    2012-11-01

    In this report a textile azo dye Remazol orange was degraded and detoxified by bacterium Pseudomonas aeruginosa BCH in plain distilled water. This bacterial decolorization performance was found to be pH and temperature dependent with maximum decolorization observed at pH 8 and temperature 30 °C. Bacterium tolerated higher dye concentrations up to 400 mg l(-1). Effect of initial cell mass showed that higher cell mass concentration can accelerate decolorization process with maximum of 92 % decolorization observed at 2.5 g l(-1) cell mass within 6.5 h. Effect of various metal ions showed Mn has inducing effect whereas Zn strongly inhibited the decolorization process at 5 mM concentration. Analysis of biodegradation products carried out with UV-vis spectroscopy, HPTLC and FTIR confirmed the decolorization and degradation of Remazol orange. Possible route for the degradation of dye was proposed based on GC-MS analysis. During toxicological scrutiny in Allium cepa root cells, induction in the activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX) and inhibition of catalase (CAT) along with raised levels of lipid peroxidation and protein oxidation in dye treated samples were detected which conclusively indicated the generation of oxidative stress. Less toxic nature of the dye degraded products was observed after bacterial treatment.

  5. Mouse hepatic oval cells require Met-dependent PI3K to impair TGF-β-induced oxidative stress and apoptosis.

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    Adoración Martínez-Palacián

    Full Text Available We have previously shown that oval cells harboring a genetically inactivated Met tyrosine kinase (Met(-/- oval cells are more sensitive to TGF-β-induced apoptosis than cells expressing a functional Met (Met(flx/flx, demonstrating that the HGF/Met axis plays a pivotal role in oval cell survival. Here, we have examined the mechanism behind this effect and have found that TGF-β induced a mitochondria-dependent apoptotic cell death in Met(flx/flx and Met(-/- oval cells, associated with a marked increase in levels of the BH3-only proteins Bim and Bmf. Bmf plays a key role during TGF-β-mediated apoptosis since knocking down of BMF significantly diminished the apoptotic response in Met(-/- oval cells. TGF-β also induced oxidative stress accompanied by NADPH oxidase 4 (Nox4 mRNA up-regulation and decreased protein levels of antioxidant enzymes. Antioxidants inhibit both TGF-β-induced caspase 3 activity and Bmf up-regulation, revealing an oxidative stress-dependent Bmf regulation by TGF-β. Notably, oxidative stress-related events were strongly amplified in Met(-/- oval cells, emphasizing the critical role of Met in promoting survival. Pharmacological inhibition of PI3K did impair HGF-driven protection from TGF-β-induced apoptosis and increased sensitivity of Met(flx/flx oval cells to TGF-ß by enhancing oxidative stress, reaching apoptotic indices similar to those obtained in Met(-/- oval cells. Interestingly, both PI3K inhibition and/or knockdown itself resulted in caspase-3 activation and loss of viability in Met(flx/flx oval cells, whereas no effect was observed in Met(-/- oval cells. Altogether, results presented here provide solid evidences that both paracrine and autocrine HGF/Met signaling requires PI3K to promote mouse hepatic oval cell survival against TGF-β-induced oxidative stress and apoptosis.

  6. The Forkhead box transcription factor FOXM1 is required for the maintenance of cell proliferation and protection against oxidative stress in human embryonic stem cells

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    C.T.D. Kwok

    2016-05-01

    Full Text Available Human embryonic stem cells (hESCs exhibit unique cell cycle structure, self-renewal and pluripotency. The Forkhead box transcription factor M1 (FOXM1 is critically required for the maintenance of pluripotency in mouse embryonic stem cells and mouse embryonal carcinoma cells, but its role in hESCs remains unclear. Here, we show that FOXM1 expression was enriched in undifferentiated hESCs and was regulated in a cell cycle-dependent manner with peak levels detected at the G2/M phase. Expression of FOXM1 did not correlate with OCT4 and NANOG during in vitro differentiation of hESCs. Importantly, knockdown of FOXM1 expression led to aberrant cell cycle distribution with impairment in mitotic progression but showed no profound effect on the undifferentiated state. Interestingly, FOXM1 depletion sensitized hESCs to oxidative stress. Moreover, genome-wide analysis of FOXM1 targets by ChIP-seq identified genes important for M phase including CCNB1 and CDK1, which were subsequently confirmed by ChIP and RNA interference analyses. Further peak set comparison against a differentiating hESC line and a cancer cell line revealed a substantial difference in the genomic binding profile of FOXM1 in hESCs. Taken together, our findings provide the first evidence to support FOXM1 as an important regulator of cell cycle progression and defense against oxidative stress in hESCs.

  7. Tamarind seed coat ameliorates fluoride induced cytotoxicity, oxidative stress, mitochondrial dysfunction and apoptosis in A549 cells.

    Science.gov (United States)

    Ameeramja, Jaishabanu; Panneerselvam, Lakshmikanthan; Govindarajan, Vimal; Jeyachandran, Sivakamavalli; Baskaralingam, Vaseeharan; Perumal, Ekambaram

    2016-01-15

    Fluoride (F) is an environmental contaminant and industrial pollutant. Molecular mechanisms remain unclear in F induced pulmonary toxicity even after numerous studies. Tamarind fruits act as defluoridating agents, but no study was conducted in in vitro systems. Hence, we aimed to assess the ameliorative impact of the tamarind seed coat extract (TSCE) against F toxicity utilizing lung epithelial cells, A549. Cells were exposed to sodium fluoride (NaF-5 mM) alone and in combination with TSCE (750 ng/ml) or Vitamin C (positive control) for 24 h and analyzed for F content, intracellular calcium ([Ca(2+)]i) level, oxidative stress, mitochondrial integrity and apoptotic markers. TSCE treatment prevented the F induced alterations in [Ca(2+)]i overload, F content, oxidant (reactive oxygen species generation, lipid peroxidation, protein carbonyl content and nitric oxide) and antioxidant (superoxide dismutase, catalase, glutathione peroxidase and glutathione) parameters. Further, TSCE modulates F activated changes in mitochondrial membrane potential, permeability transition pore opening, cytochrome-C release, Bax/Bcl-2 ratio, caspase-3 and PARP-1 expressions. In conclusion, our study demonstrated that TSCE as a potential protective agent against F toxicity, which can be utilized as a neutraceutical.

  8. Inhibition of Autophagy Enhances Curcumin United light irradiation-induced Oxidative Stress and Tumor Growth Suppression in Human Melanoma Cells

    Science.gov (United States)

    Niu, Tianhui; Tian, Yan; Mei, Zhusong; Guo, Guangjin

    2016-01-01

    Malignant melanoma is the most aggressive form of skin carcinoma, which possesses fast propagating and highly invasive characteristics. Curcumin is a natural phenol compound that has various biological activities, such as anti-proliferative and apoptosis-accelerating impacts on tumor cells. Unfortunately, the therapeutical activities of Cur are severely hindered due to its extremely low bioavailability. In this study, a cooperative therapy of low concentration Cur combined with red united blue light irradiation was performed to inspect the synergistic effects on the apoptosis, proliferation and autophagy in human melanoma A375 cell. The results showed that red united blue light irradiation efficaciously synergized with Cur to trigger oxidative stress-mediated cell death, induce apoptosis and inhibit cell proliferation. Meanwhile, Western blotting revealed that combined disposure induced the formation of autophagosomes. Conversely, inhibition of the autophagy enhanced apoptosis, obstructed cell cycle arrest and induced reversible proliferation arrest to senescence. These findings suggest that Cur combined with red united blue light irradiation could generate photochemo-preventive effects via enhancing apoptosis and triggering autophagy, and pharmacological inhibition of autophagy convert reversible arrested cells to senescence, therefore reducing the possibility that damaged cells might escape programmed death. PMID:27502897

  9. The Nrf1 and Nrf2 Balance in Oxidative Stress Regulation and Androgen Signaling in Prostate Cancer Cells

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    Michelle A. Schultz

    2010-06-01

    Full Text Available Reactive oxygen species (ROS signaling has recently sparked a surge of interest as being the molecular underpinning for cancer cell survival, but the precise mechanisms involved have not been completely elucidated. This review covers the possible roles of two ROS-induced transcription factors, Nrf1 and Nrf2, and the antioxidant proteins peroxiredoxin-1 (Prx-1 and Thioredoxin-1 (Txn-1 in modulating AR expression and signaling in aggressive prostate cancer (PCa cells. In androgen independent (AI C4-2B cells, in comparison to the parental androgen dependent (AD LNCaP cells, we present evidence of high Nrf1 and Prx-1 expression and low Nrf2 expression in these aggressive PCa cells. Furthermore, in DHT treated C4-2B cells, increased expression of the p65 (active isoform of Nrf1 correlated with enhanced AR transactivation. Our findings implicate a crucial balance of Nrf1 and Nrf2 signaling in regulating AR activity in AI-PCa cells. Here we will discuss how understanding the mechanisms by which oxidative stress may affect AR signaling may aid in developing novel therapies for AI-PCa.

  10. Water-soluble fractions from defatted sesame seeds protect human neuroblast cells against peroxyl radicals and hydrogen peroxide-induced oxidative stress.

    Science.gov (United States)

    Ben Othman, Sana; Katsuno, Nakako; Kitayama, Akemi; Fujimura, Makoto; Kitaguchi, Kohji; Yabe, Tomio

    2016-09-01

    Oxidative stress is involved in the development of aging-related diseases, such as neurodegenerative diseases. Dietary antioxidants that can protect neuronal cells from oxidative damage play an important role in preventing such diseases. Previously, we reported that water-soluble fractions purified from defatted sesame seed flour exhibit good antioxidant activity in vitro. In the present study, we investigated the protective effects of white and gold sesame seed water-soluble fractions (WS-wsf and GS-wsf, respectively) against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) induced oxidative stress in human neuroblast SH-SY5Y cells. Pretreatment with WS-wsf and GS-wsf did not protect cells against AAPH-induced cytotoxicity, while simultaneous co-treatment with AAPH significantly improved cell viability and inhibited membrane lipid peroxidation. These results suggest that WS-wsf and GS-wsf protect cells from AAPH-induced extracellular oxidative damage via direct scavenging of peroxyl radicals. When oxidative stress was induced by H2O2, pretreatment WS-wsf and GS-wsf significantly enhanced cell viability. These results suggest that in addition to radical scavenging, WS-wsf and GS-wsf enhance cellular resistance to intracellular oxidative stress by activation of the Nrf-2/ARE pathway as confirmed by the increased Nrf2 protein level in the nucleus and increased heme oxygenase 1 (HO-1) mRNA expression. The roles of ferulic and vanillic acids as bioactive antioxidants in these fractions were also confirmed. In conclusion, our results indicated that WS-wsf and GS-wsf, which showed antioxidant activity in vitro, are also efficient antioxidants in a cell system protecting SH-SY5Y cells against both extracellular and intracellular oxidative stress.

  11. Bioaccessible (poly)phenol metabolites from raspberry protect neural cells from oxidative stress and attenuate microglia activation.

    Science.gov (United States)

    Garcia, Gonçalo; Nanni, Sara; Figueira, Inês; Ivanov, Ines; McDougall, Gordon J; Stewart, Derek; Ferreira, Ricardo B; Pinto, Paula; Silva, Rui F M; Brites, Dora; Santos, Cláudia N

    2017-01-15

    Neuroinflammation is an integral part of the neurodegeneration process inherent to several aging dysfunctions. Within the central nervous system, microglia are the effective immune cells, responsible for neuroinflammatory responses. In this study, raspberries were subjected to in vitro digestion simulation to obtain the components that result from the gastrointestinal (GI) conditions, which would be bioaccessible and available for blood uptake. Both the original raspberry extract and the gastrointestinal bioaccessible (GIB) fraction protected neuronal and microglia cells against H2O2-induced oxidative stress and lipopolysaccharide (LPS)-induced inflammation, at low concentrations. Furthermore, this neuroprotective capacity was independent of intracellular ROS scavenging mechanisms. We show for the first time that raspberry metabolites present in the GIB fraction significantly inhibited microglial pro-inflammatory activation by LPS, through the inhibition of Iba1 expression, TNF-α release and NO production. Altogether, this study reveals that raspberry polyphenols may present a dietary route to the retardation or amelioration of neurodegenerative-related dysfunctions.

  12. Astaxanthin treatment confers protection against oxidative stress in U937 cells stimulated with lipopolysaccharide reducing O2- production.

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    Sara Franceschelli

    Full Text Available Recently, astaxanthin (ASTA studies have focused on several biological functions such as radical scavenging, singlet oxygen quenching, anti-carcinogenesis, anti-diabetic, anti-obesity, anti-inflammatory, anti-melanogenesis, and immune enhancement activities. In this study, we investigated the potential role protective of ASTA, an antioxidant marine carotenoid, in restoring physiological conditions in U937 cells stimulated with LPS (10 µg/ml. Our results show that pre-treatment with ASTA (10 µM for 1 h attenuates the LPS-induced toxicity and ROS production. The beneficial effect of ASTA is associated with a reduction intracellular O2 (- production by restoring the antioxidant network activity of superoxide dismutase (SOD and catalase (CAT, which influence HO-1 expression and activity by inhibiting nuclear translocation of Nrf2. We accordingly hypothesize that ASTA has therapeutic properties protecting U937 cells from LPS-induced inflammatory and oxidative stress.

  13. (Pro)renin receptor mediates both angiotensin II-dependent and -independent oxidative stress in neuronal cells.

    Science.gov (United States)

    Peng, Hua; Li, Wencheng; Seth, Dale M; Nair, Anand R; Francis, Joseph; Feng, Yumei

    2013-01-01

    The binding of renin or prorenin to the (pro)renin receptor (PRR) promotes angiotensin (Ang) II formation and mediates Ang II-independent signaling pathways. In the central nervous system (CNS), Ang II regulates blood pressure via inducing oxidative stress; however, the role of PRR-mediated Ang II-independent signaling pathways in oxidative stress in the CNS remains undefined. To address this question, Neuro-2A cells were infected with control virus or an adeno-associated virus encoding the human PRR. Human PRR over-expression alone increased ROS levels, NADPH oxidase activity, as well as NADPH oxidase (NOX) isoforms 2 and 4 mRNA expression levels and these effects were not blocked by losartan. Moreover, the increase in NOX 2 and NOX 4 mRNA levels, NADPH oxidase activity, and ROS levels induced by PRR over-expression was prevented by mitogen activated protein kinase/extracellular signal-regulated kinase 1 and 2 (MAPK/ERK1/2) inhibition, and phosphoinositide 3 kinase/Akt (IP3/Akt) inhibition, indicating that PRR regulates NOX activity and ROS formation in neuro-2A cells through Ang II-independent ERK1/2 and IP3/Akt activation. Interestingly, at a concentration of 2 nM or higher, prorenin promoted Ang II formation, and thus further increased the ROS levels in cultured Neuro-2A cells via PRR. In conclusion, human PRR over-expression induced ROS production through both angiotensin II-dependent and -independent mechanisms. We showed that PRR-mediated angiotensin II-independent ROS formation is associated with activation of the MAPK/ERK1/2 and PI3/Akt signaling pathways and up-regulation of mRNA level of NOX 2 and NOX4 isoforms in neuronal cells.

  14. Red blood cells in Rett syndrome: oxidative stress, morphological changes and altered membrane organization.

    Science.gov (United States)

    Ciccoli, Lucia; De Felice, Claudio; Leoncini, Silvia; Signorini, Cinzia; Cortelazzo, Alessio; Zollo, Gloria; Pecorelli, Alessandra; Rossi, Marcello; Hayek, Joussef

    2015-11-01

    In this review, we summarize the current evidence on the erythrocyte as a previously unrecognized target cell in Rett syndrome, a rare (1:10 000 females) and devastating neurodevelopmental disorder caused by loss-of-function mutations in a single gene (i.e. MeCP2, CDKL5, or rarely FOXG1). In particular, we focus on morphological changes, membrane oxidative damage, altered membrane fatty acid profile, and aberrant skeletal organization in erythrocytes from patients with typical Rett syndrome and MeCP2 gene mutations. The beneficial effects of ω-3 polyunsaturated fatty acids (PUFAs) are also summarized for this condition to be considered as a 'model' condition for autism spectrum disorders.

  15. Protective effects of ginkgo biloba leaves extract on peroxide-induced oxidative stress damage in PC12 cells

    Institute of Scientific and Technical Information of China (English)

    Weiqiang Chen; Taiping Hu; Ying Liu

    2007-01-01

    BACKGROUND: Extracts of ginkgo biloba leaves (EGB) and its metabolites have been reported to enhance brain function and nerve behavior. It has also been hypothesized that they can protect neurons from oxidative stress.OBJECTIVE: To investigate protective effects of EGB on peroxide (H2O2)-induced oxidative stress damage in PC12 cells.DESIGN: Observational contrast study.SETTING: Department of Pathophysiology, Guangdong Pharmacological College.MATERIALS: EGB was provided by Xi'an Fujie Biotechnological Development Company; 1640 culture medium, methylthiazolyl tetrazolium (MTT), trypsin and dimathyl sulfoxide (DMSO) by Sigma Company;PC 12 cell strain by Cell Center of Medical College of Zhongshan University; calf serum by Hangzhou Sijiqing Bioengineering Company; lactate dehydrogenase (LDH) kit by Nanjing Jiancheng Bioengineering Research Institute.METHODS: The experiment was carried out in Department of Cell Biology of Guangdong Pharmacological College from June to December 2005.①Cell culture: PC 12 cells were cultured in 1640 medium containing 200 g/L fetal calf serum. The cells were diluted to 1×107 L-1 and washed every two days. Those cells were used to experiment until they grew in logarithm on solid wall.②Grouping and intervention: PC 12 cells(1×108L-1) were plated in 96-well plates with the density of 200 μL/hole and divided into three groups:normal control group (routinely adding media), H2O2 group (treating with media and H2O2 for 20 hours) and EGB group (adding media, 100 μ mol/L EGB and 100 μmol/L H2O2).③MTT assay: PC12 cells (1×108L-1) were plated in 96-well plates and divided into three groups with 8 holes for each group. Under sterile condition, cells were added with 5 g/L MTT (100 μ L) and cultured for 4 hours. And then, 200 μL DMSO fluid was added and shaken for 30 minutes until blue crystal products formed were dissolved soundly.④Experimental evaluation: Absorbance (A) at 630 nm was measured and LDH activity was measured at the same

  16. Melatonin alleviates hyperthyroidism induced oxidative stress and neuronal cell death in hippocampus of aged female golden hamster, Mesocricetus auratus.

    Science.gov (United States)

    Rao, Geeta; Verma, Rakesh; Mukherjee, Arun; Haldar, Chandana; Agrawal, Neeraj Kumar

    2016-09-01

    Oxidative stress is a well known phenomenon under hyperthyroid condition that induces various physiological and neural problems with a higher prevalence in females. We, therefore investigated the antioxidant potential of melatonin (Mel) on hyperthyroidism-induced oxidative stress and neuronal cell death in the hippocampus region of brain (cognition and memory centre) of aged female golden hamster, Mesocricetus auratus. Aged female hamsters were randomly divided into four experimental groups (n=7); group-I: control, group-II: Melatonin (5mgkg(-1)day(-1), i.p., for one week), group-III: Hyperthyroid (100μg kg(-1)day(-1), i.p., for two weeks) and group-IV- Hyper+Mel. Hormonal profiles (thyroid and melatonin), activity of antioxidant enzymes (SOD, CAT and GPX), lipid peroxidation level (TBARS) and the specific apoptotic markers (Bax/Bcl-2 ratio and Caspase-3) expression were evaluated. A significant increase in the profile of total thyroid hormone (tT3 and tT4) in hyperthyroidic group as compared to control while tT3 significantly decreased in melatonin treated hyperthyroidic group. However, Mel level significantly decreased in hyperthyroidic group but increased in melatonin treated hyperthyroidic group. Further, the number of immune-positive cells for thyroid hormone receptor-alpha (TR-α) decreased in the hippocampus of hyperthyroidic group and increased in melatonin treated hyperthyroidic group. Profiles of antioxidant enzymes showed a significant decrease in hyperthyroidic group with a simultaneous increase in lipid peroxidation (TBARS). Melatonin treatment to hyperthyroidic group lead to decreased TBARS level with a concomitant increase in antioxidant enzyme activity. Moreover, increased expression of Bax/Bcl-2 ratio and Caspase-3, in hyperthyroidic group had elevated neuronal cell death in hippocampal area and melatonin treatment reduced its expression in hyperthyroidic group. Our findings thus indicate that melatonin reduced the hyperthyroidism

  17. Salvianolic Acid B (Sal B Protects Retinal Pigment Epithelial Cells from Oxidative Stress-Induced Cell Death by Activating Glutaredoxin 1 (Grx1

    Directory of Open Access Journals (Sweden)

    Xiaobin Liu

    2016-11-01

    Full Text Available Protein glutathionylation, defined as the formation of protein mixed disulfides (PSSG between cysteine residues and glutathione (GSH, can lead to cell death. Glutaredoxin 1 (Grx1 is a thiol repair enzyme which catalyzes the reduction of PSSG. Therefore, Grx1 exerts strong anti-apoptotic effects by improving the redox state, especially in times of oxidative stress. However, there is currently no compound that is identified as a Grx1 activator. In this study, we identified and characterized Salvianolic acid B (Sal B, a natural compound, as a Grx1 inducer, which potently protected retinal pigment epithelial (RPE cells from oxidative injury. Our results showed that treatment with Sal B protected primary human RPE cells from H2O2-induced cell damage. Interestingly, we found Sal B pretreatment upregulated Grx1 expression in RPE cells in a time- and dose-dependent manner. Furthermore, NF-E2-related factor 2 (Nrf2, the key transcription factor that regulates the expression of Grx1, was activated in Sal B treated RPE cells. Further investigation showed that knockdown of Grx1 by small interfering RNA (siRNA significantly reduced the protective effects of Sal B. We conclude that Sal B protects RPE cells against H2O2-induced cell injury through Grx1 induction by activating Nrf2 pathway, thus preventing lethal accumulation of PSSG and reversing oxidative damage.

  18. Salvianolic Acid B (Sal B) Protects Retinal Pigment Epithelial Cells from Oxidative Stress-Induced Cell Death by Activating Glutaredoxin 1 (Grx1).

    Science.gov (United States)

    Liu, Xiaobin; Xavier, Christy; Jann, Jamieson; Wu, Hongli

    2016-11-03

    Protein glutathionylation, defined as the formation of protein mixed disulfides (PSSG) between cysteine residues and glutathione (GSH), can lead to cell death. Glutaredoxin 1 (Grx1) is a thiol repair enzyme which catalyzes the reduction of PSSG. Therefore, Grx1 exerts strong anti-apoptotic effects by improving the redox state, especially in times of oxidative stress. However, there is currently no compound that is identified as a Grx1 activator. In this study, we identified and characterized Salvianolic acid B (Sal B), a natural compound, as a Grx1 inducer, which potently protected retinal pigment epithelial (RPE) cells from oxidative injury. Our results showed that treatment with Sal B protected primary human RPE cells from H₂O₂-induced cell damage. Interestingly, we found Sal B pretreatment upregulated Grx1 expression in RPE cells in a time- and dose-dependent manner. Furthermore, NF-E2-related factor 2 (Nrf2), the key transcription factor that regulates the expression of Grx1, was activated in Sal B treated RPE cells. Further investigation showed that knockdown of Grx1 by small interfering RNA (siRNA) significantly reduced the protective effects of Sal B. We conclude that Sal B protects RPE cells against H₂O₂-induced cell injury through Grx1 induction by activating Nrf2 pathway, thus preventing lethal accumulation of PSSG and reversing oxidative damage.

  19. Meloxicam inhibits fipronil-induced apoptosis via modulation of the oxidative stress and inflammatory response in SH-SY5Y cells.

    Science.gov (United States)

    Park, Jae Hyeon; Park, Youn Sun; Lee, Je-Bong; Park, Kyung-Hun; Paik, Min-kyoung; Jeong, Mihye; Koh, Hyun Chul

    2016-01-01

    Oxidative stress and inflammatory responses have been identified as key elements of neuronal cell apoptosis. In this study, we investigated the mechanisms by which inflammatory responses contribute to apoptosis in human neuroblastoma SH-SY5Y cells treated with fipronil (FPN). Based on the cytotoxic mechanism of FPN, we examined the neuroprotective effects of meloxicam against FPN-induced neuronal cell death. Treatment of SH-SY5Y cells with FPN induced apoptosis via activation of caspase-9 and -3, leading to nuclear condensation. In addition, FPN induced oxidative stress and increased expression of cyclooxygenase-2 (COX-2) and tumor necrosis factor-α (TNF-α) via inflammatory stimulation. Pretreatment of cells with meloxicam enhanced the viability of FPN-exposed cells through attenuation of oxidative stress and inflammatory response. FPN activated mitogen activated protein kinase (MAPK) and inhibitors of MAPK abolished FPN-induced COX-2 expression. Meloxicam also attenuated FPN-induced cell death by reducing MAPK-mediated pro-inflammatory factors. Furthermore, we observed both nuclear accumulation of p53 and enhanced levels of cytosolic p53 in a concentration-dependent manner after FPN treatment. Pretreatment of cells with meloxicam blocked the translocation of p53 from the cytosol to the nucleus. Together, these data suggest that meloxicam may exert anti-apoptotic effects against FPN-induced cytotoxicity by both attenuating oxidative stress and inhibiting the inflammatory cascade via inactivation of MAPK and p53 signaling.

  20. Neuroprotective effect of Amaranthus lividus and Amaranthus tricolor and their effects on gene expression of RAGE during oxidative stress in SH-SY5Y cells.

    Science.gov (United States)

    Amornrit, W; Santiyanont, R

    2016-04-26

    Amaranthus plants, or spinach, are used as food sources worldwide. Amaranthus leaves are rich in antioxidant compounds, which act as free radical scavengers. Oxidative stress caused by the aberrant production of reactive oxygen species (ROS) represents an important mechanism for neuronal dysfunction and cell loss in different neurodegenerative disorders. The neuroprotective effects of antioxidant-containing plants have been extensively demonstrated in different models of neurotoxicity. However, few studies have investigated the antioxidant properties of Amaranthus extracts and their effect on the nervous system. In the present study, the leaves of Amaranthus lividus and Amaranthus tricolor were extracted using petroleum ether, dichloromethane, and methanol. Results indicated that antioxidant activities were the highest in methanol extracts from both kinds of Amaranthus leaves. In addition, oxidative stress was induced in human neuroblastoma cell lines (SH-SY5Y) by using H2O2. Intracellular oxidative stress, cytotoxicity, and gene expression of RAGE were then determined. In vitro results demonstrated that pretreatment with A. lividus and A. tricolor extracts can significantly decrease cell toxicity and intracellular ROS production in SH-SY5Y cells. Interestingly, the extracts also significantly downregulated the expression of oxidative stress genes such as HMOX-1, RAGE, and RelA/ NF-κB. Our results suggested that Amaranthus leaves may be useful for reducing oxidative stress and may be beneficial for age-related diseases and neurodegenerative disorders.

  1. Lasting effect of preceding culture conditions on the susceptibility of C6 cells to peroxide-induced oxidative stress.

    Science.gov (United States)

    Brenner, Sibylle; Gülden, Michael; Maser, Edmund; Seibert, Hasso

    2010-12-01

    The aim of the present study was to investigate the influence of the maintenance culture conditions on the competence of C6 rat glioma cells to cope with peroxide-induced oxidative stress. C6 cells were maintained either in Ham's nutrient mixture F-10 supplemented with 15% horse serum and 2.5% foetal bovine serum (FBS) or in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 5% FBS. The differently cultured cells were exposed under identical conditions to hydrogen peroxide (H₂O₂) and cumene hydroperoxide (CHP) in serum-free DMEM. The cells maintained in high serum Ham's F-10 medium (1) were less sensitive towards the cytotoxic action of both peroxides (EC₅₀-values: H₂O₂: 193 ± 23 μM; CHP: 94 ± 16 μM) than the cells maintained in low serum DMEM (EC₅₀-values: H₂O₂: 51 ± 10 μM; CHP: 27 ± 11 μM), (2) eliminated the peroxides (initial concentration: 100 μM) with higher rates (H₂O₂: 56 ± 5.5 vs. 32 ± 2.7, CHP: 32 ± 6 vs. 3.4 ± 0.6 nmol/min mg protein), (3) contained more glutathione (30 ± 2.5 vs. 14 ± 1.1 nmol/mg protein) and (4) owned a higher glutathione peroxidase activity (28 ± 3.4 vs. 9.5 ± 0.8 mU/mg protein). Glutathione reductase and catalase activities were not affected. These results demonstrate that the preceding culture conditions have a lasting effect on the susceptibility of cultured cells to oxidative stressors like peroxides. As cause for these differences a dissimilar supply of the cells with serum born antioxidants like selenium and α-tocopherol is discussed.

  2. Acetaminophen and NAPQI are toxic to auditory cells via oxidative and endoplasmic reticulum stress-dependent pathways.

    Science.gov (United States)

    Kalinec, Gilda M; Thein, Pru; Parsa, Arya; Yorgason, Joshua; Luxford, William; Urrutia, Raul; Kalinec, Federico

    2014-07-01

    Pain relievers containing N-acetyl-para-aminophenol, also called APAP, acetaminophen or paracetamol, in combination with opioid narcotics are top-selling pharmaceuticals in the U.S. Individuals who abuse these drugs for as little as sixty days can develop tinnitus and progressive bilateral sensorineural hearing loss. Recently published studies indicate that APAP and its metabolic product N-acetyl-p-benzoquinoneimine (NAPQI) are the primary ototoxic agents in this type of pain relievers. However, the mechanisms underlying the deleterious effects of these drugs on auditory cells remain to be fully characterized. In this study, we report cellular, genomic, and proteomic experiments revealing that cytotoxicity by APAP and NAPQI involves two different pathways in Immortomouse-derived HEI-OC1 cells, implicating ROS overproduction, alterations in ER morphology, redistribution of intra-cisternal chaperones, activation of the eIF2α-CHOP pathway, as well as changes in ER stress and protein folding response markers. Thus, both oxidative and ER stress are part of the cellular and molecular mechanisms that contribute to the cytotoxic effects of APAP and NAPQI in these cells. We suggest that these in vitro findings should be taken into consideration when designing pharmacological strategies aimed at preventing the toxic effects of these drugs on the auditory system.

  3. Neuroprotective biflavonoids of Chamaecyparis obtusa leaves against glutamate-induced oxidative stress in HT22 hippocampal cells.

    Science.gov (United States)

    Jeong, Eun Ju; Hwang, Lim; Lee, Mina; Lee, Ki Yong; Ahn, Mi-Jeong; Sung, Sang Hyun

    2014-02-01

    Four biflavonoids (1-4), five flavonoids glycosides (5-9), two catechins (10, 11), two lignans (12-13), neolignan glycoside (14) and phenylpropanoid glycoside (15) were isolated from the leaves of Chamaecyparis obtusa (Cupressaceae). Neuroprotective effects of the isolated compounds were evaluated employing HT22 mouse hippocampal cells, a model system to study glutamate-induced oxidative stress. The glutamate injured HT22 cells were protected significantly by amentoflavone (3), ginkgetin (4) and (-)-epitaxifolin 3-O-β-D-xylopyranoside (9). The reduced activities of antioxidant enzymes, superoxide dismutase (SOD), glutathione reductase (GR) in response to high concentration of glutamate were preserved by pre-treatment of 3, 4 or 9, while the activities of glutathione peroxidase (Gpx) and catalase (CAT) were little affected. The reduced content of GSH induced by glutamate was also recovered by 3, 4 or 9 in accommodation with the decrease in ROS production. In addition, the phosphorylation of ERK1/2 induced by glutamate insult was clearly prevented by 3, while little changed by 4. Taken together, amentoflavone (3), ginkgetin (4) and (-)-epitaxifolin 3-O-β-D-xylopyranoside (9) derived from C. obtusa could protect HT22 neuronal cells against glutamate-induced oxidative damage through preserving antioxidant enzymes activities and/or inhibiting ERK1/2 activation.

  4. Dietary Saccharomyces cerevisiae Cell Wall Extract Supplementation Alleviates Oxidative Stress and Modulates Serum Amino Acids Profiles in Weaned Piglets

    Science.gov (United States)

    Yu, Lei; Martínez, Yordan

    2017-01-01

    This research aims to evaluate the effects of dietary supplementation with Saccharomyces cerevisiae cell wall extract (SCCWE) on growth performance, oxidative stress, intestinal morphology, and serum amino acid concentration in weaned piglets. Utilizing a completely randomized design, 40 healthy piglets weaned at 21 d were grouped into 4 experimental treatments with 10 pigs per treatment group. Treatments consisted of a basal diet (T0), a basal diet with a 0.05% SCCWE (T1), a basal diet with a 0.10% SCCWE (T2), and a basal diet with a 0.15% SCCWE (T3). SCCWE supplementation increased the average daily gain and final body weight compared with T0 (P < 0.05). SCCWE in T2 and T3 improved the average daily feed intake and decreased the feed/gain ratio compared with T1 and T2 (P < 0.05). SCCWE decreased serum malondialdehyde (MDA) and increased activities of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) significantly compared to T0 (P < 0.05). SCCWE increased the concentration of Ile compared to T0 (P < 0.05). Moreover, the concentrations of Leu, Phe, and Arg were higher in T2 and T3 (P < 0.05). These findings indicate beneficial effects of SCCWE supplementation on growth performance, the concentration of some essential amino acids, and alleviation of oxidative stress in weaned piglets.

  5. P2X7 Receptor as a Key Player in Oxidative Stress-Driven Cell Fate in Nonalcoholic Steatohepatitis

    Directory of Open Access Journals (Sweden)

    Saurabh Chatterjee

    2015-01-01

    Full Text Available Incidences of nonalcoholic fatty liver disease parallels increase in the global obesity epidemic. NAFLD has been shown to be associated with risks of cardiometabolic disorders and kidney disturbances. It is accompanied by insulin and leptin resistance that complicate the diagnosis and treatment of this public health menace. Though significant research is underway for understanding the molecular mechanisms of NAFLD and its subsequent inflammatory and fibrotic manifestations like nonalcoholic steatohepatitis, the role of purinergic receptors has been unclear. It is increasingly being recognized that damage associated molecular patterns like NAD and ATP that are released from injured cells via hepatocellular injury either by oxidative stress or lipotoxicity from steatosis activate the purinergic receptor. Based on evidence from inflammatory responses in the airways and vasculature and autoimmune complications in humans and rodents, it is beyond doubt that hepatocellular inflammation such as that seen in NASH can result from the activation of purinergic receptors. This event can result in the formation of inflammasomes and can be an important pathway for the progression of NASH. The present review evaluates the current knowledge of the role of oxidative stress and its signaling via P2X7 receptors in hepatocellular injury that might contribute to the NASH pathophysiology.

  6. Alteration of oxidative stress parameters in red blood cells of rats after chronic in vivo treatment with cisplatin and selenium

    Directory of Open Access Journals (Sweden)

    Marković Snežana D.

    2011-01-01

    Full Text Available In this study we evaluated the possible protective effects of selenium (Se on hematological and oxidative stress parameters in rats chronically treated with cisplatin (cisPt. Four groups of Wistar albino rats were examined: a control, untreated rats (I, rats treated with Se (II, rats treated with cisPt (III, and rats treated with Se and cisPt (IV. All animals were treated for 5 days successively and killed 24 h after the last treatment. Hematological and oxidative stress parameters were followed in whole blood and red blood cells (RBC. Results showed that the chronic application of Se was followed by a higher number of reticulocytes and platelets, increased lipid peroxidation and GSH content in the RBC. Cisplatin treatment induced depletion of RBC and platelet numbers and an elevation of the superoxide anion, nitrites and glutathione levels. Se and cisPt co-treatment was followed by an elevation of the hematological parameters and the recovery of the glutathione status when compared to the control and cisPt-treated rats.

  7. Peroxisomes,oxidative stress,and inflammation

    Institute of Scientific and Technical Information of China (English)

    Stanley; R; Terlecky; Laura; J; Terlecky; Courtney; R; Giordano

    2012-01-01

    Peroxisomes are intracellular organelles mediating a wide variety of biosynthetic and biodegradative reactions.Included among these are the metabolism of hydrogen peroxide and other reactive species,molecules whose levels help define the oxidative state of cells.Loss of oxidative equilibrium in cells of tissues and organs potentiates inflammatory responses which can ultimately trigger human disease.The goal of this article is to review evidence for connections between peroxisome function,oxidative stress,and inflammation in the context of human health and degenerative disease.Dysregulated points in this nexus are identified and potential remedial approaches are presented.

  8. Pathway of programmed cell death and oxidative stress induced by β-hydroxybutyrate in dairy cow abomasum smooth muscle cells and in mouse gastric smooth muscle.

    Directory of Open Access Journals (Sweden)

    Wulin Tian

    Full Text Available The administration of exogenous β-hydroxybutyrate (β-HB, as well as fasting and caloric restriction, is a condition associated with β-HB abundance and decreased appetite in animals. Increased β-HB and decreased appetite exist simultaneously in some diseases, such as bovine left displaced abomasums (LDA and human chronic gastritis. However, the effects of β-HB on stomach injuries have not been explored. To elucidate the possible effects of exogenous β-HB on the stomach, mice were injected intraperitoneally with β-HB, and bovine abomasum smooth muscle cells (BSMCs were treated with different concentrations of β-HB. We found that β-HB induced BSMCs endoplasmic reticulum- and mitochondria-mediated apoptotic cell death. β-HB promoted Bax expression and caspase-12, -9, and -3 activation while blocking Bcl-2 expression. β-HB also promoted AIF, EndoG release and p53 expression. β-HB acted on key molecules in the apoptotic cell death pathway and increased p38 and c-June NH2-terminal kinase phosphorylation while inhibiting ERK phosphorylation and PCNA expression. β-HB upregulated P27 and P21 mRNA levels while downregulating cyclin and CDK mRNA levels, arresting the cell cycle. These results suggest that BSMCs treated with β-HB can induce oxidative stress, which can be prevented by intracellular calcium chelators BAPTA/AM but not antioxidant NAC. Additionally, these results suggest that β-HB causes ROS generation through a Ca2+-dependent mechanism and that intracellular Ca2+ levels play a critical role in β-HB -induced apoptotic cell death. The impact of β-HB on programmed cell death and oxidative stress in vivo was confirmed in murine experiments. For the first time, we show oxidative stress effects of β-HB on smooth muscle. We propose that β-HB is a possible cause of some stomach diseases, including bovine LDA.

  9. Perinatal Oxidative Stress May Affect Fetal Ghrelin Levels in Humans

    OpenAIRE

    Zhong-Cheng Luo; Jean-François Bilodeau; Anne Monique Nuyt; Fraser, William D; Pierre Julien; Francois Audibert; Lin Xiao; Carole Garofalo; Emile Levy

    2015-01-01

    In vitro cell model studies have shown that oxidative stress may affect beta-cell function. It is unknown whether oxidative stress may affect metabolic health in human fetuses/newborns. In a singleton pregnancy cohort (n = 248), we studied maternal (24–28 weeks gestation) and cord plasma biomarkers of oxidative stress [malondialdehyde (MDA), F2-isoprostanes] in relation to fetal metabolic health biomarkers including cord plasma glucose-to-insulin ratio (an indicator of insulin sensitivity), p...

  10. Mechanisms of oxidative stress-induced cell death in hepatocytes : targets for protective intervention

    NARCIS (Netherlands)

    Conde de la Rosa, Laura

    2006-01-01

    Oxidatieve stress is de schadelijke blootstelling aan reactieve zuurstofverbindingen zoals waterstof peroxide, superoxide anionen en hydroxyl radicalen. Oxidatieve stress treedt op bij veel leverziekten, onder ander bij een ernstige complicatie van insuline-ongevoeligheid bij diabetes type II. Hepat

  11. 1,4-benzoquinone-induced STAT-3 hypomethylation in AHH-1 cells: Role of oxidative stress

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2015-01-01

    Full Text Available Benzene, a known occupational and environmental contaminant, is associated with increased risk of leukemia. The objectives of this study were to elucidate the regulatory mechanism of the hypomethylated STAT3 involved in benzene toxicity in vitro. As 1,4-benzoquinone (1,4-BQ is one of benzene’s major toxic metabolites, AHH-1 cells were treated by 1,4-BQ for 24 h with or without pretreatment of the antioxidant a-LA or the methyltransferase inhibitor, 5-aza-2′ deoxycytidine (5-aza. The cell viability was investigated using the 3-(4, 5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. ROS was determined via 2′,7′-dichlorodihydrofluorescein diacetate (DCFDA flow cytometric assays. The level of oxidative stress marker 8-OHdG was measured by enzyme-linked immunosorbent assay. Methylation-specific PCR was used to detect the methylation status of STAT3. Results indicated the significantly increasing expression of ROS and 8-OHdG which accompanied with STAT3 hypomethylation in 1,4-BQ-treated AHH-1 cells. α-LA suppressed the expression of both ROS and 8-OHdG, simultaneously reversed 1,4-BQ-induced STAT3 hypomethylation. However, although the methylation inhibitor, 5-aza reduced the expression level of ROS and 8-OHdG, but had no obvious inhibiting effect on STAT3 methylation level. Taken together, oxidative stress are involved 1,4-BQ-induced STAT3 methylation expression.

  12. Protective effect of liquiritin on oxidative stress injury of SH-EP1 cell lines caused by hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    Ning Shi; Hong-ju Guo; Huan Wang; Yu-Xin Fan; Yu-Min Zhang; Li-Rong Chang

    2017-01-01

    Objective:To study the protective effect of liquiritin on the oxidative stress injury of SH-EP1 cell lines caused by hydrogen peroxide.Methods: SH-EP1 cell lines were cultured and randomly divided into control group, H2O2 group and liquiritin group that were treated with the culture medium without serum, 200 μmol/L H2O2 as well as 100 μmol/L, 200 μmol/L and 400 μmol/L liquiritin combined with 200 μmol/L H2O2 respectively. After treatment, cell viability values as well as the content of mitochondrial apoptosis molecules and antioxidant molecules in cells were determined.Results:After 12 h, 24 h, 36 h and 48 h of treatment, the cell viability values of H2O2 group were significantly lower than those of control group, the cell viability values of 100 μmol/L, 200 μmol/L and 400 μmol/L liquiritin group were significantly higher than those of H2O2 group and the larger the liquiritin dosage, the higher the cell viability value; after 24 h of treatment, Bax, Caspase-3, Nrf2 and ARE content of H2O2 group were significantly higher than those of control group while Bcl-2, XIAP, SOD, GHS-Px and HO-1 content were significantly lower than those of control group; Bax and Caspase-3 content of 100 μmol/L, 200 μmol/L and 400 μmol/L liquiritin group were significantly lower than those of H2O2 group while Bcl-2, XIAP, Nrf2, ARE, SOD, GHS-Px and HO-1 content were significantly higher than those of H2O2group, and the larger the liquiritin dosage, the lower the Bax and Caspase-3 content while the higher the Bcl-2, XIAP, Nrf2, ARE, SOD, GHS-Px and HO-1 content.Conclusions:Liquiritin can inhibit the mitochondrial apoptosis and enhance the antioxidant system function to relieve the oxidative stress injury of SH-EP1 cell lines caused by hydrogen peroxide.

  13. Induction of autophagy by salidroside through the AMPK-mTOR pathway protects vascular endothelial cells from oxidative stress-induced apoptosis.

    Science.gov (United States)

    Zheng, Xiang-Tao; Wu, Zi-Heng; Wei, Ye; Dai, Ju-Ji; Yu, Guan-Feng; Yuan, FengLai; Ye, Le-Chi

    2017-01-01

    Vascular endothelial cells are highly sensitive to oxidative stress, and this is one of the mechanisms by which widespread endothelial dysfunction is induced in most cardiovascular diseases and disorders. However, how these cells can survive in oxidative stress environments remains unclear. Salidroside, a traditional Chinese medicine, has been shown to confer vascular protective effects. We aimed to understand the role of autophagy and its regulatory mechanisms by treating human umbilical vein endothelial cells (HUVECs) with salidroside under