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1.
Altered oxidative stress has long been observed in cancer cells, and this biochemical property of cancer cells represents
a specific vulnerability that can be exploited for therapeutic benefit. The major role of an elevated oxidative stress for
the efficacy of molecular targeted drugs is under investigation. Menadione is considered an attractive model for the study
of oxidative stress, which can induce apoptosis in human leukemia HL-60 cell lines. Prostaglandin E2 (PGE2) via its receptors not only promotes cell survival but also reverses apoptosis and promotes cancer progression. Here, we
present evidence for the biological role of PGE2 as a protective agent of oxidative stress-induced apoptosis in monocytic cells. Pretreatment of HL-60 cells with PGE2 markedly ameliorated the menadione-induced apoptosis and inhibited the degradation of PARP and lamin B. The EP2 receptor antagonist AH6809 abrogated the inhibitory effect of PGE2, suggesting the role of the EP2/cAMP system. The PKA inhibitor H89 also reversed apoptosis and decreased the PKA activity that was elevated 10-fold by PGE2. The treatment of HL-60 cells with NAC or zinc chloride showed a similar protective effect as with PGE2 on menadione-treated cells. Furthermore, PGE2 activated the Ras/Raf/MEK pathway, which in turn initiated ERK activation, and ultimately protected menadione-induced apoptosis.
These results imply that PGE2 via cell survival pathways may protect oxidative stress-induced apoptosis in monocytic cells. This study warrants further
pre-clinical investigation as well as application towards leukemia clinics. 相似文献
2.
Sanjeev Kumar Avinash Appukuttan Abdelouahid Maghnouj Stephan Hahn H. Peter Reusch Yury Ladilov 《Apoptosis : an international journal on programmed cell death》2014,19(7):1069-1079
Apoptosis of vascular smooth muscle cells (VSMC) significantly contributes to the instability of advanced atherosclerotic plaques. Oxygen radicals are an important cause for VSMC death. However, the precise mechanism of oxidative stress-induced VSMC apoptosis is still poorly understood. Here, we aimed to analyse the role of soluble adenylyl cylclase (sAC). VSMC derived from rat aorta were treated with either H2O2 (300 µmol/L) or DMNQ (30 µmol/L) for 6 h. Oxidative stress-induced apoptosis was prevented either by treatment with 30 µmol/L KH7 (a specific inhibitor of sAC) or by stable sAC-knockdown (shRNA-transfection). A similar effect was found after inhibition of protein kinase A (PKA). Suppression of the sAC/PKA-axis led to a significant increase in phosphorylation of the p38 mitogen-activated protein kinase under oxidative stress accompanied by a p38-dependent phosphorylation/inactivation of the pro-apoptotic Bcl-2-family protein Bad. Pharmacological inhibition of p38 reversed these effects of sAC knockdown on apoptosis and Bad phosphorylation, suggesting p38 as a link between sAC and apoptosis. Analysis of the protein phosphatases 1 and 2A activities revealed an activation of phosphatase 1, but not phosphatase 2A, under oxidative stress in a sAC/PKA-dependent manner and its role in controlling the p38 phosphorylation. Inhibition of protein phosphatase 1, but not 2A, prevented the pro-apoptotic effect of oxidative stress. In conclusion, sAC/PKA-signaling plays a key role in the oxidative stress-induced apoptosis of VSMC. The cellular mechanism consists of the sAC-promoted and protein phosphatase 1-mediated suppression of p38 phosphorylation resulting to activation of the mitochondrial pathway of apoptosis. 相似文献
3.
C Colussi M C Albertini S Coppola S Rovidati F Galli L Ghibelli 《FASEB journal》2000,14(14):2266-2276
H2O2 treatment on U937 cells leads to the block of glycolytic flux and the inactivation of glyceraldehyde-3-phosphate-dehydrogenase by a posttranslational modification (possibly ADP-ribosylation). Glycolysis spontaneously reactivates after 2 h of recovery from oxidative stress; thereafter cells begin to undergo apoptosis. The specific ADP-ribosylation inhibitor 3-aminobenzamide inhibits the stress-induced inactivation of glyceraldehyde-3-phosphate-dehydrogenase and the block of glycolysis; concomitantly, it anticipates and increases apoptosis. Exogenous block of glycolysis (i.e., by culture in glucose-free medium or with glucose analogs or after NAD depletion), turns the transient block into a stable one: this results in protection from apoptosis, even when downstream cell metabolism is kept active by the addition of pyruvate. All this evidence indicates that the stress-induced block of glycolysis is not the result of a passive oxidative damage, but rather an active cell reaction programmed via ADP-ribosylation for cell self-defense. 相似文献
4.
Rui-Yao Zhu Di Zhang Han-Dong Zou Xiao-Shu Zuo Qing-Shan Zhou He Huang 《In vitro cellular & developmental biology. Animal》2016,52(10):1020-1025
MicroRNAs play critical roles in regulating cell survival under multiple pathological conditions of heart diseases. Oxidative stress-induced apoptosis contributes greatly to heart ischemia-reperfusion injury. Herein, we describe a novel regulatory role of miR-28 on the survival of cardiomyocytes. We show that miR-28 was upregulated in cardiomyocytes treated with hydrogen peroxide (H2O2). MiR-28 gain of function sensitized cell apoptosis, whereas miR-28 loss of function partially rescued cell apoptosis induced by H2O2. Importantly, we observed a significant reduction in Akt/mammalian target of rapamycin (mTOR) signaling activity after miR-28 treatment. Luciferase activity assay and western blot analysis both revealed that, phosphoinositide-dependent kinase-1 (PDK1), which is critical for Akt activation, was directly and negatively modulated by miR-28. Our results therefore indicate that miR-28 regulates oxidative stress-induced cell apoptosis in heart muscle cells, which possibly involves a PDK1/Akt/mTOR-dependent mechanism. MIR-28 could serve as a critical therapeutic target to diminish oxidative stress-induced cell death in the heart. 相似文献
5.
Background
Oxidative stress is known to be involved in most of the aetiological factors of nasopharyngeal carcinoma (NPC). Cells that are under oxidative stress may undergo apoptosis. We have previously demonstrated that oxidative stress-induced apoptosis could be a potential mechanism mediating chromosome breakages in nasopharyngeal epithelial cells. Additionally, caspase-activated DNase (CAD) may be the vital player in mediating the chromosomal breakages during oxidative stress-induced apoptosis. Chromosomal breakage occurs during apoptosis and chromosome rearrangement. Chromosomal breakages tend to cluster in certain regions, such as matrix association region/scaffold attachment region (MAR/SAR). We hypothesised that oxidative stress-induced apoptosis may result in chromosome breaks preferentially at the MAR/SAR sites. The AF9 gene at 9p22 was targeted in this study because 9p22 is a deletion site commonly found in NPC.Results
By using MAR/SAR recognition signature (MRS), potential MAR/SAR sites were predicted in the AF9 gene. The predicted MAR/SAR sites precisely match to the experimentally determined MAR/SARs. Hydrogen peroxide (H2O2) was used to induce apoptosis in normal nasopharyngeal epithelial cells (NP69) and NPC cells (HK1). Nested inverse polymerase chain reaction was employed to identify the AF9 gene cleavages. In the SAR region, the gene cleavage frequency of H2O2-treated cells was significantly higher than that of the non-treated cells. A few chromosomal breakages were detected within the AF9 region which was previously found to be involved in the mixed lineage leukaemia (MLL)-AF9 translocation in an acute lymphoblastic leukaemia patient. As for the non-SAR region, no significant difference in the gene cleavage frequency was found between the untreated control and H2O2-treated cells. Furthermore, H2O2-induced cleavages within the SAR region were reduced by caspase-3 inhibitor, which indirectly inhibits CAD.Conclusions
These results reaffirm our previous findings that oxidative stress-induced apoptosis could be one of the potential mechanisms underlying chromosome breakages in nasopharyngeal epithelial cells. MAR/SAR may play a vital role in defining the location of chromosomal breakages mediated by oxidative stress-induced apoptosis, where CAD is the major nuclease.6.
Nandan K. Mondal Tieluo Li Zengsheng Chen Hegang H. Chen Erik N. Sorensen Si M. Pham Michael A. Sobieski Steven C. Koenig Mark S. Slaughter Bartley P. Griffith Zhongjun J. Wu 《Molecular and cellular biochemistry》2017,425(1-2):125-138
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 oxidative stress. HUVECs were treated with salidroside and exposed to hydrogen peroxide (H2O2). The results indicated that salidroside exerted cytoprotective effects in an H2O2-induced HUVEC injury model and suppressed H2O2-induced apoptosis of HUVECs. Pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, increased oxidative stress-induced HUVEC apoptosis, while the autophagy activator rapamycin induced anti-apoptosis effects in HUVECs. Salidroside increased autophagy and decreased apoptosis of HUVECs in a dose-dependent manner under oxidative stress. Moreover, 3-MA attenuated salidroside-induced HUVEC autophagy and promoted apoptosis, whereas rapamycin had no additional effects compared with salidroside alone. Salidroside upregulated AMPK phosphorylation but downregulated mTOR phosphorylation under oxidative stress; however, administration of compound C, an AMPK inhibitor, abrogated AMPK phosphorylation and increased mTOR phosphorylation and apoptosis compared with salidroside alone. These results suggest that autophagy is a protective mechanism in HUVECs under oxidative stress and that salidroside might promote autophagy through activation of the AMPK pathway and downregulation of mTOR pathway. 相似文献
7.
Summary In previous studies, oxidants such as hydrogen peroxide (H2O2) or hydroperoxy fatty acids were shown to induce apoptosis in the CEM human T cell line as demonstrated by the cleavage of cellular DNA into a 180-base pair ladder. Oxidant-induced DNA fragmentation was detectable within 3 h and inhibitable by various antioxidants. In the present study, apoptosis is shown to also be induced by the addition of low doses (0.1–3 mM) of N-acetyl-L-cysteine (NAC), reduced glutathione (GSH) or cysteine. By contrast, higher concentrations (10 mM) of the same thiols displayed a paradoxical lack of toxicity. Thiol-induced apoptosis was completely prevented by the addition of BAPTA-AM, an intracellular calcium chelator, or by simultaneous treatment with 5 mM pyruvate which forms a thiazolidine complex with sulfhydryl compounds. Catalase or glutathione peroxidase, but not Superoxide dismutase, protected the cells from thiol-induced apoptosis demonstrating a role for H2O2. The ability of thiol compounds to either evoke or prevent oxidative stress implies a unique role for these agents in the control of apoptosis in lymphoid cells. 相似文献
8.
Wei-xiang Tang Li-kui Wang Yi-qiao Wang Zhi-jun Zong Zhi-xin Gao Xue-sheng Liu Yu-jun Shen Yu-xian Shen Yuan-hai Li 《Molecular and cellular biochemistry》2014,385(1-2):179-190
Live ischemia–reperfusion injury is associated with endoplasmic reticulum (ER) stress-induced apoptosis. Activation of peroxisome proliferator-activated receptor-α (PPARα) may inhibit hepatocyte apoptosis induced by oxidative stress and protect against liver injury. This study aimed to investigate the effects of PPARα activation, through a specific agonist, on ER stress-induced apoptosis in human liver hepatocellular carcinoma (HepG2) cells. HepG2 cells were challenged with H2O2 and treated with WY14643, a selective PPARα agonist, in the presence or absence of the PPARα antagonist of MK886. Cell viable assay (MTT) and immunostaining were used to evaluate cell viability. The level of apoptotic cell death was quantified through Annexin V/PI staining. Alanine aminotransferase, asparatate aminotransferase, and malondialdehyde levels were measured to determine the presence of cellular injury and oxidative stress. RT-PCR and Western blot analysis were used to detect mRNA and protein expression of PPARα, BiP, and CHOP. Immunofluorescence was utilized to determine the intracellular localization of CHOP. H2O2 and MK886 both reduced the viability of HepG2 cells, increased oxidative stress and apoptosis, up-regulated the BiP and CHOP expression, and induced CHOP translocation from the cytoplasm to the nucleus. Compared with cells treated with H2O2 alone, pre-administration of WY14643 increased cell viability, attenuated apoptosis, improved cell function, down-regulated BiP and CHOP expression and inhibited CHOP translocation. The effects of WY14643 were completely abolished using the MK886 antagonist. PPARα activation protects against H2O2-induced HepG2 cell apoptosis. The underlying mechanisms may be associated with its activation to suppress excessive ER stress. 相似文献
9.
The regulation of CO2 production from [U-14C]glutamine and C2 of [2-14C]pyruvate was investigated in cultured bovine adrenocortical cells, and the effect of alterations in the relative rates of oxidation of these substrates on cell proliferation, particularly in the presence of an inhibitor of transamination reactions, was examined. 14CO2 production from 2 mM [U-14C]glutamine and 2 mM [2-14C]pyruvate was measured in the presence of 100 μM 2,4-dinitrophenol, an uncoupler of oxidative phosphorylation. Treatment of primary cultures for 24 h with 50 μM cortisol increased the oxidation of [14C]glutamine relative to that of [14C]pyruvate, an effect dependent on prior low cell density. Cortisol treatment also resulted in a prolonged delay in the onset of proliferation from low density, and completely inhibited growth in the presence of 2 mM aminooxyacetate, which reduces mitochondrial utilization of glutamine. The effects on glutamine and pyruvate metabolism and on cell growth, with or without aminooxyacetate, were prevented by simultaneous treatment with the antioxidants dimethyl sulfoxide (10 mM) and butylated hydroxyanisole (100 μM), suggesting the involvement of lipid peroxidation in the action of cortisol, as previously demonstrated for its action on 11β-hydroxylase. During continued proliferation of adrenocortical cells in the absence of cortisol there was also a slower increase in the oxidation of [14C]glutamine relative to that of [14C]pyruvate as a function of population doubling level. The rate of this increase was slowed by growth of cells in 2% O2 rather than the standard 19% O2, and accelerated by continued growth of cells in the presence of cortisol. The rate of increase in the oxidation of [14C]glutamine relative to that of [14C]pyruvate under these three conditions correlated with inhibition of cell growth by aminooxyacetate. In contrast to the complete inhibition of growth in aminooxyacetate demonstrated by cortisol-treated cells, control cells (19% O2) did proliferate, although growth was limited, whereas cells at 2% O2 proliferated to a much greater extent. In the absence of aminooxyacetate the rate of growth in primary adrenocortical cell cultures under these three conditions was similar. Lipid peroxidation appears to make cultured adrenocortical cells dependent on glutamine for mitochondrial function and proliferation by inhibiting the utilization of the normal substrate, pyruvate. 相似文献
10.
Aerobic organisms experience oxidative stress due to generation of reactive oxygen species during normal aerobic metabolism.
In addition, several chemicals also generate reactive oxygen species which induce oxidative stress. Thus oxidative stress
constitutes a major threat to organisms living in aerobic environments. Programmed cell death or apoptosis is a physiological
mechanism of cell death, that probably evolved with multicellularity, and is indispensable for normal growth and development.Dictyostelium discoideum, an eukaryotic developmental model, shows both unicellular and multicellular forms in its life cycle and exhibits apparent
caspase-independent programmed cell death, and also shows high resistance to oxidative stress. An attempt has been made to
investigate the biochemical basis for high resistance ofD. discoideum cell death induced by different oxidants. Dose-dependent induction of cell death by exogenous addition of hydrogen peroxide
(H2O2),in situ generation of H2O2 by hydroxylamine, and nitric oxide (NO) generation by sodium nitroprusside treatment inD. discoideum were studied. The AD50 doses (concentration of the oxidants cusing 50% of the cells to die) after 24 h of treatment were found to be 0.45 mM, 4
mM and 1 mM, respectively. Studies on enzymatic antioxidant status ofD. discoideum when subjected to oxidative stress, NO and nutrient stress reveal that superoxide dismutase and catalase were unchanged;
a significant induction of glutathione peroxidase was observed. Interestingly, oxidative stress-induced lipid membrane peroxidative
damage could not be detected. The results shed light on the biochemical basis for the observed high resistance to oxidative
stress inD. discoideum. 相似文献
11.
In the hydrogen peroxide (H2O2) apoptosis model of the murine thymocyte, redox reactant and antioxidant pyruvate prevents programmed cell death. We tested the hypothesis that such protection was mediated, at least in part, via pyruvate handling by mitochondrial metabolism. Cultured bovine pulmonary artery endothelial cells were incubated for 30 min with 0.5 mM H2O2 in the absence and presence of 0.5 mM -cyano-3-hydroxycinnamate, as a selective inhibitor of the mitochondrial pyruvate transporter. In controls H2O2 decreased cell viability by 30% within 24 h; this was associated with apoptosis-like bodies, nuclear condensation, and biochemical DNA damage consistent with programmed cell death. Pyruvate (0.1–20 mM) enhanced cell viability in a dose-dependent manner, with 85% viable cells at 3 mM and no DNA laddering, no positive nick-end labeling (TUNEL), and no detectable Annexin V or propidium iodide staining. In contrast, using 5 mM L-lactate as a cytosolic reductant or acetate as a redox-neutral substrate, cell death increased to 40%, which was associated with intense DNA laddering, positive TUNEL and Hoechst 33258 assays. -Cyano-3-hydroxycinnamate alone did not significantly decrease endothelial viability but reduced viability from 85 ± 3 to 71 ± 4% (p = 0.023) in presence of 3 mM pyruvate plus H2O2; pathological cell morphology and DNA laddering under the same conditions suggested loss of pyruvate protection against apoptosis. Since -cyano-3-hydroxycinnamate re-distributed medium pyruvate and L-lactate consistent with selective blockade of pyruvate uptake into the mitochondria, the findings support the hypothesis that pyruvate protection against H2O2 apoptosis is mediated in part via the mitochondrial matrix compartment. Possible mediators include anti-apoptotic bcl-2 and/or products of mitochondrial pyruvate metabolism such as citrate that affect metabolic regulation and anti-oxidant status in the cytoplasm. 相似文献
12.
Song J Li J Mourot JM Evers BM Chung DH 《Biochemical and biophysical research communications》2008,375(2):200-204
We recently demonstrated that protein kinase D (PKD) exerts a protective function during oxidative stress-induced intestinal epithelial cell injury; however, the exact role of DAG kinase (DGK)ζ, an isoform expressed in intestine, during this process is unknown. We sought to determine the role of DGK during oxidative stress-induced intestinal cell injury and whether DGK acts as an upstream regulator of PKD. Inhibition of DGK with R59022 compound or DGKζ siRNA transfection decreased H2O2-induced RIE-1 cell apoptosis as measured by DNA fragmentation and increased PKD phosphorylation. Overexpression of kinase-dead DGKζ also significantly increased PKD phosphorylation. Additionally, endogenous nuclear DGKζ rapidly translocated to the cytoplasm following H2O2 treatment. Our findings demonstrate that DGK is involved in the regulation of oxidative stress-induced intestinal cell injury. PKD activation is induced by DGKζ, suggesting DGK is an upstream regulator of oxidative stress-induced activation of the PKD signaling pathway in intestinal epithelial cells. 相似文献
13.
Rudo F. Mapanga Uthra Rajamani Nonkululeko Dlamini Makhosazane Zungu-Edmondson Roisin Kelly-Laubscher Mohammed Shafiullah Athiq Wahab Mohamed Y. Hasan Mohamed A. Fahim Philippe Rondeau Emmanuel Bourdon M. Faadiel Essop 《PloS one》2012,7(10)
Diabetes constitutes a major health challenge. Since cardiovascular complications are common in diabetic patients this will further increase the overall burden of disease. Furthermore, stress-induced hyperglycemia in non-diabetic patients with acute myocardial infarction is associated with higher in-hospital mortality. Previous studies implicate oxidative stress, excessive flux through the hexosamine biosynthetic pathway (HBP) and a dysfunctional ubiquitin-proteasome system (UPS) as potential mediators of this process. Since oleanolic acid (OA; a clove extract) possesses antioxidant properties, we hypothesized that it attenuates acute and chronic hyperglycemia-mediated pathophysiologic molecular events (oxidative stress, apoptosis, HBP, UPS) and thereby improves contractile function in response to ischemia-reperfusion. We employed several experimental systems: 1) H9c2 cardiac myoblasts were exposed to 33 mM glucose for 48 hr vs. controls (5 mM glucose); and subsequently treated with two OA doses (20 and 50 µM) for 6 and 24 hr, respectively; 2) Isolated rat hearts were perfused ex vivo with Krebs-Henseleit buffer containing 33 mM glucose vs. controls (11 mM glucose) for 60 min, followed by 20 min global ischemia and 60 min reperfusion ± OA treatment; 3) In vivo coronary ligations were performed on streptozotocin treated rats ± OA administration during reperfusion; and 4) Effects of long-term OA treatment (2 weeks) on heart function was assessed in streptozotocin-treated rats. Our data demonstrate that OA treatment blunted high glucose-induced oxidative stress and apoptosis in heart cells. OA therapy also resulted in cardioprotection, i.e. for ex vivo and in vivo rat hearts exposed to ischemia-reperfusion under hyperglycemic conditions. In parallel, we found decreased oxidative stress, apoptosis, HBP flux and proteasomal activity following ischemia-reperfusion. Long-term OA treatment also improved heart function in streptozotocin-diabetic rats. These findings are promising since it may eventually result in novel therapeutic interventions to treat acute hyperglycemia (in non-diabetic patients) and diabetic patients with associated cardiovascular complications. 相似文献
14.
Liu X Ren Z Zhan R Wang X Wang X Zhang Z Leng X Yang Z Qian L 《Cell stress & chaperones》2009,14(3):311-319
Oxidative stress is one of the main causes of myocardial injury, which is associated with cardiomyocyte death. Mitochondria
play a key role in triggering the necrosis and apoptosis pathway of cardiomyocytes under oxidative stress. Although prohibitin
(PHB) has been acknowledged as a mitochondrial chaperone, its functions in cardiomyocytes are poorly characterized. The present
research was designed to investigate the cardioprotective role of PHB in mitochondria. Oxidative stress can increase the PHB
content in mitochondria in a time-dependent manner. Overexpression of PHB in cultured cardiomyocytes by transfection of recombinant
adenovirus vector containing PHB sense cDNA resulted in an increase of PHB in mitochondria. Compared with the non-transfection
cardiomyocytes, PHB overexpression could protect the mitochondria from oxidative stress-induced injury. The mitochondria-mediated
apoptosis pathway was consistently suppressed in PHB-overexpressed cardiomyocytes after hydrogen peroxide (H2O2) treatment, including a reduced change in mitochondrial membrane permeability transition and an inhibited release of cytochrome
c from mitochondria to cytoplasma. As a result, the oxidative stress-induced cardiomyocyte apoptosis was suppressed. These
data indicated that PHB protected the cardiomyocytes from oxidative stress-induced damage, and that increasing PHB content
in mitochondria constituted a new therapeutic target for myocardium injury.
XiaoHua Liu and Zhe Ren contributed equally to this work.
● Prohibitin is an evolutionarily conserved and ubiquitously expressed protein involved in mitochondrial structure, function,
and inheritance whose function in cardiomyocyte is not known. In this study, we found oxidative stress could induce increased
expression in cardiomyocytes and mitochondrial translocation of PHB, and PHB can protect against oxidative stress in cultured
neonatal cardiomyocyte. 相似文献
15.
The physiology and biochemistry of Sarcina ventriculi was studied in order to determine adaptations made by the organism to changes in environmental pH. The organism altered carbon and electron flow from acetate, formate and ethanol production at neutral pH, to predominantly ethanol production at pH 3.0. Increased levels of pyruvate dehydrogenase (relative to pyruvate decarboxylase) and acetaldehyde dehydrogenase occurred when the organism was grown at neutral pH, indicating the predominance of carbon flux through the oxidative branch of the pathway for pyruvate metabolism. When the organism was grown at acid pH, there was a significant increase in pyruvate decarboxylase levels and a decrease in acetaldehyde dehydrogenase, causing flux through the non-oxidative branch of the pathway. CO2 reductase and formate dehydrogenase were not regulated as a function of growth pH. Pyruvate dehydrogenase possessed Michaelis-Menten kinetics for pyruvate with an apparent K
m of 2.5 mM, whereas pyruvate decarboxylase exhibited sigmoidal kinetics, with a S0.5 of 12.0 mM. Differences in total protein banding patterns from cells grown at pH extremes suggested that synthesis of pyruvate decarboxylase and other enzymes was in part responsible for metabolic regulation of the fermentation products formed. 相似文献
16.
Seyed E. Hasnain Tarvinder K. Taneja Nand K. Sah Manjari Mohan Niteen Pathak Sudhir Sahdev Mohammad Athar Satish M. Totey Rasheedunnisa Begum 《Journal of biosciences》1999,24(1):13-19
Cellular imbalance in the levels of antioxidants and reactive oxygen species (ROS) is directly associated with a number of
pathological states and results in programmed cell death or apoptosis. We demonstrate the use ofin vitro culturedSpodoptera frugiperda (sf9) insect cells as a model to study oxidative stress induced programmed cell death. Apoptosis ofin vitro cultured sf9 cells was induced by the exogenous treatment of H2O2 to cells growing in culture. The AD50 (concentration of H2O2 inducing about 50% apoptotic response) varied with the duration of treatment, batch to batch variation of H2O2 and the physiological state of cells. At 24 h post-treatment with H2O2 AD50 was about 475 Μm. Apoptosis could also be induced byin situ generation of H2O2 by the inhibition of catalase activity upon hydroxylamine treatment. Hydroxylamine acted synergistically with H2O2 with an AD50 of 2.2 mM. DMSO, a free radical scavenger, inhibited H2O2-induced apoptosis thereby confirming the involvement of reactive oxygen species. Exposure of cells to UV radiation (312 nm)
resulted in a dose-dependent induction of apoptosis. These results provide evidence on the novel use of insect cells as a
model for oxidative stress-induced apoptosis. 相似文献
17.
The role of pyruvate and autocrine polypeptide factors (APF) secreted by cytotoxic IL-2-dependent CTLL-2 cells in cell defense from oxidative stress was investigated. The addition of a conditioned medium (CM) containing pyruvate and APF into CTLL-2 cell cultures significantly increased the cell survival under oxidative stress conditions induced by hydrogen peroxide (H2O2). The kinetics of (H2O2) removal from cell cultures with added CM has been registered. It has been shown that, at the beginning of oxidative stress (less than 15 min), H2O2 was mostly removed by means of its reaction with pyruvate contained in CM. Pyruvate content in CM was estimated as 138 ± 7 μM. Gel filtration on a column with Bio-Gel P-10 was used to eliminate pyruvate from CM. Gel filtration resulted in three CM fractions (A, B, and C) corresponding to three chromatogram peaks. Pyruvate was not detected in any fraction. The fraction A was the first to be eluted from the column and contained the largest molecules. In the cell survival test, fraction B had the highest protective ability for CTLL-2 cells under oxidative stress. Fraction A supported cell survival to a lesser degree and fraction C did not show any protective abilities. Fraction B added to cells under oxidative stress kept intracellular ATP content at a significantly higher level then in control cells. Moreover, it was found that APF from fraction B was able to react with H2O2 directly and inactivate it in the absence of cells. APF from fraction A did not have such properties. 相似文献
18.
Cheuk-Yiu Law Chung-Wah Siu Katherine Fan Wing-Hon Lai Ka-Wing Au Yee-Man Lau Lai-Yung Wong Jenny C.Y. Ho Yee-ki Lee Hung-Fat Tse Kwong-Man Ng 《Biochemistry and Biophysics Reports》2016
Patients with Danon disease may suffer from severe cardiomyopathy, skeletal muscle dysfunction as well as varying degrees of mental retardation, in which the primary deficiency of lysosomal membrane-associated protein-2 (LAMP2) is considerably associated. Owing to the scarcity of human neurons, the pathological role of LAMP2 deficiency in neural injury of humans remains largely elusive. However, the application of induced pluripotent stem cells (iPSCs) may shed light on overcoming such scarcity.In this study, we obtained iPSCs derived from a patient carrying a mutated LAMP2 gene that is associated with Danon disease. By differentiating such LAMP2-deficient iPSCs into cerebral cortical neurons and with the aid of various biochemical assays, we demonstrated that the LAMP2-deficient neurons are more susceptible to mild oxidative stress-induced injury.The data from MTT assay and apoptotic analysis demonstrated that there was no notable difference in cellular viability between the normal and LAMP2-deficient neurons under non-stressed condition. When exposed to mild oxidative stress (10 μM H2O2), the LAMP2-deficient neurons exhibited a significant increase in apoptosis. Surprisingly, we did not observe any aberrant accumulation of autophagic materials in the LAMP2-deficient neurons under such stress condition.Our results from cellular fractionation and inhibitor blockade experiments further revealed that oxidative stress-induced apoptosis in the LAMP2-deficient cortical neurons was caused by increased abundance of cytosolic cathepsin L. These results suggest the involvement of lysosomal membrane permeabilization in the LAMP2 deficiency associated neural injury. 相似文献
19.
Jungas T Motta I Duffieux F Fanen P Stoven V Ojcius DM 《The Journal of biological chemistry》2002,277(31):27912-27918
Cystic fibrosis is characterized by chronic inflammation and an imbalance in the concentrations of alveolar and lung oxidants and antioxidants, which result in cell damage. Modifications in lung glutathione concentrations are recognized as a salient feature of inflammatory lung diseases such as cystic fibrosis, and glutathione plays a major role in protection against oxidative stress and is important in modulation of apoptosis. The cystic fibrosis transmembrane conductance regulator (CFTR) is permeable to Cl(-), larger organic ions, and reduced and oxidized forms of glutathione, and the DeltaF508 CFTR mutation found in cystic fibrosis patients has been correlated with impaired glutathione transport in cystic fibrosis airway epithelia. Because intracellular glutathione protects against oxidative stress-induced apoptosis, we studied the susceptibility of epithelial cells (HeLa and IB3-1) expressing normal and mutant CFTR to apoptosis triggered by H(2)O(2). We find that cells with normal CFTR are more sensitive to oxidative stress-induced apoptosis than cells expressing defective CFTR. In addition, sensitivity to apoptosis could be correlated with glutathione levels, because depletion of intracellular glutathione results in higher levels of apoptosis, and glutathione levels decreased faster in cells expressing normal CFTR than in cells with defective CFTR during incubation with H(2)O(2). The pro-apoptotic BCL-2 family member, BAX, is also activated faster in cells expressing normal CFTR than in those with mutant CFTR under these conditions, and artificial glutathione depletion increases the extent of BAX activation. These results suggest that glutathione-dependent BAX activation in cells with normal CFTR represents an early step in oxidative stress-induced apoptosis of these cells. 相似文献
20.
The apoptosis of lens epithehal cells has been proposed as the common basis of cataract formation, with oxidative stress as the major cause. This study was performed to investigate the protective effect of the herbal constituent parthenolide against oxidative stress-induced apoptosis of human lens epithelial (HLE) cells and the possible molecular mechanisms involved. HLE cells (SRA01-04) were incubated with 50 μM H2O2 in the absence or presence of different doses of parthenolide (10, 20 and 50 μM). To study apoptosis, the cells were assessed by morphologic examination and Annexin V-propidium iodide double staining flow cytometry; to investigate the underlying molecular mechanisms, the expression of caspase-3 and caspase-9 were assayed by Western blot and quantitative RT-PCR, and the activities of caspase-3 and caspase-9 were measured by a Chemicon caspase colorimetric activity assay kit. Stimulated with H202 for 18 h, a high fraction of riLE cells underwent apoptosis, while in the presence ofparthenolide of different concentrations, dose-dependent blocking of HLE cell apoptosis was observed. The expression of caspase-3 and caspase-9 induced by H202 in HLE cells was significantly reduced by parthenolide both at the protein and mRNA levels, and the activation ofcaspase-3 and caspase-9 was also suppressed by parthenolide in a dose-dependent manner. In conclusion, parthenolide prevents HLE cells from oxidative stress-induced apoptosis through inhibition of the activation ofcaspase-3 and caspase-9, suggesting a potential protective effect against cataract formation. 相似文献