Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Low concentrations of As(2)O(3) (</=1 micromol/L) induce long-lasting remission in patients with acute promyelocytic leukemia (APL) without significant myelosuppressive side effects. Several groups, including ours, have shown that 0.5 to 1 micromol/L As(2)O(3) induces apoptosis in APL-derived NB4 cells, whereas other leukemic cells are resistant to As(2)O(3) or undergo apoptosis only in response to greater than 2 micromol/L As(2)O(3). In this report, we show that the ability of As(2)O(3) to induce apoptosis in leukemic cells is dependent on the activity of the enzymes that regulate cellular H(2)O(2) content. Thus, NB4 cells have relatively low levels of glutathione peroxidase (GPx) and catalase and have a constitutively higher H(2)O(2) content than U937 monocytic leukemia cells. Glutathione-S-transferase pi (GSTpi), which is important for cellular efflux of As(2)O(3), is also low in NB4 cells. Moreover, As(2)O(3) further inhibits GPX activity and increases cellular H(2)O(2) content in NB4 but not in U937 cells. Selenite pretreatment of NB4 cells increases the activity of GPX, lowers cellular H(2)O(2) levels, and renders NB4 cells resistant to 1 micromol/L As(2)O(3). In contrast, concentrations of As(2)O(3) that alone are not capable of inducing apoptosis in NB4 cells induce apoptosis in the presence of the GPx inhibitor mercaptosuccinic acid. Similar effects are observed by modulating the activity of catalase with its inhibitor, aminotriazol. More important from a therapeutic point of view, U937 and HL-60 cells, which require high concentrations of As(2)O(3) to undergo apoptosis, become sensitive to low, clinically acceptable concentrations of As(2)O(3) when cotreated with these GPx and catalase inhibitors. The induction of apoptosis by As(2)O(3) involves an early decrease in cellular mitochondrial membrane potential and increase in H(2)O(2) content, followed by cytochrome c release, caspase 3 activation, DNA fragmentation, and the classic morphologic changes of apoptosis.
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PMID:Arsenic trioxide selectively induces acute promyelocytic leukemia cell apoptosis via a hydrogen peroxide-dependent pathway. 1047 40

Doxorubicin (DOX) is a broad spectrum anthracycline antibiotic used to treat a variety of cancers. Redox activation of DOX to form reactive oxygen species has been implicated in DOX-induced cardiotoxicity. In this work we investigated DOX-induced apoptosis in cultured bovine aortic endothelial cells and cardiomyocytes isolated from adult rat heart. Exposure of bovine aortic endothelial cells or myocytes to submicromolar levels of DOX induced significant apoptosis as measured by DNA fragmentation and terminal deoxynucleotidyltransferase-mediated nick-end labeling assays. Pretreatment of cells with 100 microm nitrone spin traps, N-tert-butyl-alpha-phenylnitrone (PBN) or alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN) dramatically inhibited DOX-induced apoptosis. Ebselen (20-50 microm), a glutathione peroxidase mimetic, also significantly inhibited apoptosis. DOX (0.5-1 microm) inactivated mitochondrial complex I by a superoxide-dependent mechanism. PBN (100 microm), POBN (100 microm), and ebselen (50 microm) restored complex I activity. These compounds also inhibited DOX-induced caspase-3 activation and cytochrome c release. PBN and ebselen also restored glutathione levels in DOX-treated cells. We conclude that nitrone spin traps and ebselen inhibit the DOX-induced apoptotic signaling mechanism and that this antiapoptotic mechanism may be linked in part to the inhibition in formation or scavenging of hydrogen peroxide. Therapeutic strategies to mitigate DOX cardiotoxicity should be reexamined in light of these emerging antiapoptotic mechanisms of antioxidants.
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PMID:Doxorubicin-induced apoptosis in endothelial cells and cardiomyocytes is ameliorated by nitrone spin traps and ebselen. Role of reactive oxygen and nitrogen species. 1089 61

Proatherogenic oxidized low-density lipoprotein (oxLDL) induces endothelial apoptosis. We investigated the anti-apoptotic effects of intracellular and extracellular nitric oxide (*NO) donors, iron chelators, cell-permeable superoxide dismutase (SOD), glutathione peroxidase mimetics, and nitrone spin traps. Peroxynitrite (ONOO-)-modified oxLDL induced endothelial apoptosis was measured by DNA fragmentation, TUNEL assay, and caspase-3 activation. Results indicated the following: (i) the lipid fraction of oxLDL was primarily responsible for endothelial apoptosis. (ii) Endothelial apoptosis was potently inhibited by *NO donors and lipophilic phenolic antioxidants. OxLDL severely depleted Bcl-2 levels in endothelial cells and *NO donors restored Bcl-2 protein in oxLDL-treated cells. (iii) The pretreatment of a lipid fraction derived from oxLDL with sodium borohydride or potassium iodide completely abrogated apoptosis in endothelial cells, suggesting that lipid hydroperoxides induce apoptosis. (iv) Metalloporphyrins dramatically inhibited oxLDL-induced apoptosis in endothelial cells. Neither S-nitrosation of caspase-3 nor induction of Hsp70 appeared to play a significant role in the antiapoptotic mechanism of *NO in oxLDL-induced endothelial apoptosis. We propose that cellular lipid peroxyl radicals or lipid hydroperoxides induce an apoptotic signaling cascade in endothelial cells exposed to oxLDL, and that *NO inhibits apoptosis by scavenging cellular lipid peroxyl radicals.
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PMID:Inhibition of oxidized low-density lipoprotein-induced apoptosis in endothelial cells by nitric oxide. Peroxyl radical scavenging as an antiapoptotic mechanism. 1127 75

Oxidative injuries including apoptosis can be induced by reactive oxygen species (ROS) and reactive nitrogen species (RNS) in aerobic metabolism. We determined impacts of a selenium-dependent glutathione peroxidase-1 (GPX1) on apoptosis induced by diquat (DQ), a ROS (superoxide) generator, and peroxynitrite (PN), a potent RNS. Hepatocytes were isolated from GPX1 knockout (GPX1-/-) or wild-type (WT) mice, and treated with 0.5 mm DQ or 0.1-0.8 mm PN for up to 12 h. Loss of cell viability, high levels of apoptotic cells, and severe DNA fragmentation were produced by DQ in only GPX1-/- cells and by PN in only WT cells. These two groups of cells shared similar cytochrome c release, caspase-3 activation, and p21(WAF1/CIP1) cleavage. Higher levels of protein nitration were induced by PN in WT than GPX1-/- cells. Much less and/or slower cellular GSH depletion was caused by DQ or PN in GPX1-/- than in WT cells, and corresponding GSSG accumulation occurred only in the latter. In conclusion, it is most striking that, although GPX1 protects against apoptosis induced by superoxide-generator DQ, the enzyme actually promotes apoptosis induced by PN in murine hepatocytes. Indeed, GSH is a physiological substrate for GPX1 in coping with ROS in these cells.
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PMID:Opposite roles of selenium-dependent glutathione peroxidase-1 in superoxide generator diquat- and peroxynitrite-induced apoptosis and signaling. 1156 67

Glutathione peroxidase is an antioxidant enzyme that is involved in the control of cellular oxidative state. Recently, unregulated oxidative state has been implicated as detrimental to neural cell viability and involved in both acute and chronic neurodegeneration. In this study we have addressed the importance of a functional glutathione peroxidase in a mouse ischemia/reperfusion model. Two hours of focal cerebral ischemia followed by 24 h of reperfusion was induced via the intraluminal suture method. Infarct volume was increased three-fold in the glutathione peroxidase-1 (Gpx-1) -/- mouse compared with the wild-type mouse; this was mirrored by an increase in the level of apoptosis found at 24 h in the Gpx-1 -/- mouse compared with the wild-type mouse. Neuronal deficit scores correlated to the histologic data. We also found that activated caspase-3 expression is present at an earlier time point in the Gpx-1 -/- mice when compared with the wild-type mice, which suggests an enhanced susceptibility to apoptosis in the Gpx-1 -/- mouse. This is the first known report of such a dramatic increase, both temporally and in level of apoptosis in a mouse stroke model. Our results suggest that Gpx-1 plays an important regulatory role in the protection of neural cells in response to the extreme oxidative stress that is released during ischemia/reperfusion injury.
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PMID:Increased infarct size and exacerbated apoptosis in the glutathione peroxidase-1 (Gpx-1) knockout mouse brain in response to ischemia/reperfusion injury. 1157 47

There is a loss of myocytes in the aging heart due to necrosis and apoptosis. Oxidative stress, an apoptosis-inducing signal, may also increase in the aging heart. Cytosol and mitochondria isolated from the left and right ventricle of the hearts of 6-, 16-, and 24-mo-old male Fischer 344 rats were used to measure key markers of apoptosis and to assess oxidative stress. Cytosolic cytochrome c content was significantly elevated in the 16- and 24-mo-old animals compared with the 6-mo-old animals. Furthermore, Bcl-2, an antiapoptotic protein, showed a strong tendency to decrease with age, whereas Bax, a proapoptotic protein, remained unchanged. Apoptotic protease-activating factor 1 levels and caspase-3 activities were not different among the three age groups. Indicative of the chronic oxidative stress with age, heart mitochondria from old animals showed increases in manganese superoxide dismutase and glutathione peroxidase activity and increases in lipid peroxidation. This is the first study to report cytochrome c release from the mitochondria and alterations in Bcl-2 with age in vivo, providing a potential mechanism for the increase in apoptosis seen in the aging heart.
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PMID:Cytochrome c release from mitochondria in the aging heart: a possible mechanism for apoptosis with age. 1179 51

Necrosis and apoptosis coexist in the thyroid during goitre development and involution, but little is known about their respective causes. To test the possible role of free radicals, we analysed separately necrosis and apoptosis in male Wistar rats with depressed or normal antioxidant protection. Vitamin E-deficient and -sufficient rats were made goitrous with perchlorate in drinking water; involution was induced by repeated injection of NaI, without or with methimazole. Increase of thyroid malondialdehyde concentration and decrease of glutathione peroxidase activity confirmed the depressed antioxidant protection in vitamin E-deficient rats. Plasma thyroxine and TSH levels were not modified. Necrosis (swollen cells) and apoptosis (pyknotic cells) were quantified on histological sections. In vitamin E-sufficient rats, dead cells were very rare in control thyroids, increased 3-fold in goitre and still further during involution. Necrotic epithelial cells predominated in the goitre and their number declined after iodide supplementation, without or with methimazole. In contrast, the number of apoptotic cells and the caspase-3 activity were increased in goitre and further increased after involution, with two-thirds of pyknotic cells being observed in the interstitium. Apoptosis was prevented by methimazole. Vitamin E deficiency significantly increased total cell death and epithelial cell necrosis and induced the occurrence of much cell debris in the follicular lumen during involution, with no modification of the apoptotic reaction. These results show that the type of cell death is differentially regulated during goitre development and involution: necrosis is related to the oxidative status of the cells, while apoptosis comes with iodine-induced involution.
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PMID:Cell necrosis and apoptosis are differentially regulated during goitre development and iodine-induced involution. 1183 55

Oxidative stress induces apoptosis in liver parenchymal cells. The present study demonstrates that the substitution of fructose for glucose as sole carbon source in the incubation medium reduced apoptosis due to reoxygenation up to 50% in cultured rat hepatocytes. This anti-apoptotic action of fructose cannot be explained by the effects of this sugar on the intracellular ATP concentration and the ATP/ADP ratio. Rather, the suppression of apoptosis by fructose seems to be a consequence of remarkably higher intracellular levels of glutathione observed during reoxygenation in fructose-fed hepatocytes in contrast to glucose-fed ones. With fructose as substrate, the generation of excess reactive oxygen species (ROS) during the initial phase of reoxygenation was strongly reduced. With respect to ROS reduction and stabilization of the cellular glutathione pool fructose was found as efficient as a pretreatment of glucose fed cells with N-acetyl-L-cysteine. The enhanced metabolization of ROS by the glutathione/glutathione peroxidase system in fructose-cultured hepatocytes under reoxygenation was expected to improve their mitochondrial status so that late events in the apoptotic pathway are suppressed. This could be confirmed by the reduced release of cytochrome c from mitochondria into the cytosol as well as by the observed decrease of caspase-3 activity during reoxygenation.
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PMID:Fructose inhibits apoptosis induced by reoxygenation in rat hepatocytes by decreasing reactive oxygen species via stabilization of the glutathione pool. 1185 82

Potential of sanguiin H-6, a component of Sanguisorbae Radix, to protect against oxidative damage in renal mitochondria and apoptosis mediated by peroxynitrite (ONOO(-)) was examined using a model in which rats were injected with lipopolysaccharide (LPS) and then subjected to renal ischemia followed reperfusion (LPS plus ischemia-reperfusion). Ischemia-reperfusion was achieved by occluding bilateral renal artery for 60 min and then releasing for 350 min. At 50 min after ischemia started, LPS was injected intravenously. LPS plus ischemia-reperfusion induced a large amount of 3-nitrotyrosine, an oxidative product of protein that is produced via ONOO(-) nitration, which was not detectable in normal group. Oxidative damage of mitochondria was indicated by an accumulated thiobarbituric acid (TBA)-reactive substance, glutathione (GSH) depletion and glutathione peroxidase (GSH-Px) inactivation in the mitochondria. Treatment of rats with sanguiin H-6 (10 mg/kg body weight/day) for 30 days prior to LPS plus ischemia-reperfusion attenuated the oxidative damage in the mitochondria. The amount of TBA-reactive substance was decreased and the GSH levels significantly increased as compared with that in control group. However, its effect on GSH-Px activity was much weaker. Apoptosis induced by LPS plus ischemia-reperfusion was detected by fluorescence staining, TdT-mediated dUTP-biotin nick end labeling and electrophoretic analysis. Sanguiin H-6 appeared to inhibit apoptosis, and this was associated with the suppression of caspase-3 activity. These beneficial effects of sanguiin H-6 against oxidative damage in mitochondria and apoptosis contributed to the improvement in renal function by reversing the elevated levels of blood urea nitrogen and creatinine caused by ONOO(-).
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PMID:Potential of sanguiin H-6 against oxidative damage in renal mitochondria and apoptosis mediated by peroxynitrite in vivo. 1218 96

Reactive oxygen species (ROS) can directly induce or enhance tumor necrosis factor (TNF)-mediated apoptosis in a number of different cell lines. To test the relevance of intracellular ROS in modulating apoptotic signaling in vivo, we evaluated hepatocellular apoptosis mediated by the TNF or Fas receptor in wild-type and glutathione peroxidase-1 (Gpx1-/-)-deficient mice (129SV/B6 background). Apoptosis developed in livers of wild-type animals 4-6 h after intraperitoneal administration of 700 mg/kg galactosamine/100 micro g/kg endotoxin. Apoptosis was indicated by processing of procaspases-3 (assessed by western blotting), a fivefold increase in caspase-3 activity (DEVD-AMC as substrate), and a 44-fold increase in DNA fragmentation (ELISA). The time course and magnitude of apoptosis were the same in Gpx1-/- mice. In contrast, Gpx1-/- mice had higher plasma alanine aminotransferase (ALT) levels and more severe hemorrhage compared to wild-type animals at 6 h. Treatment of wild-type mice with the anti-Fas antibody Jo-2 (0.6 mg/kg i.v.) resulted in processing of procaspase-3 and a sevenfold increase in caspase-3 activity in both wild-type and Gpx1-/- mice. However, higher plasma ALT values in Gpx1-/- mice at 3 h may reflect a trend to develop more rapidly secondary necrosis. These data suggest that, under our experimental conditions, intracellular ROS did not modulate the death receptor-initiated apoptotic signaling cascade in hepatocytes. As Gpx1 is located in the cytosol and in mitochondria, which are the main cellular compartments involved in apoptotic signaling, our findings indicate that the oxidant stress in vivo was insufficient to modulate these signaling pathways. However, Gpx1 deficiency enhances the susceptibility for secondary necrosis or neutrophil-induced cell injury.
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PMID:Reactive oxygen as modulator of TNF and fas receptor-mediated apoptosis in vivo: studies with glutathione peroxidase-deficient mice. 1247 May


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