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)

Ca(2+) overload and reactive oxygen species can injure mitochondria during ischemia and reperfusion. We hypothesized that mitochondrial injury occurs during cardiac resuscitation, causing release of cytochrome c to the cytosol and bloodstream while activating apoptotic pathways. Plasma cytochrome c was measured using reverse-phase HPLC and Western immunoblotting in rats subjected to 4 or 8 min of untreated ventricular fibrillation and 8 min of closed-chest resuscitation followed by 240 min of postresuscitation hemodynamic observation. A sham group served as control. Plasma cytochrome c rose progressively to levels 10-fold higher than in sham rats 240 min after resuscitation (P < 0.01), despite reversal of whole body ischemia (decreases in arterial lactate). Cytochrome c levels were inversely correlated with left ventricular stroke work (r = -0.40, P = 0.02). Western immunoblotting of left ventricular tissue demonstrated increased levels of 17-kDa cleaved caspase-3 fragments in the cytosol. Plasma cytochrome c was then serially measured in 12 resuscitated rats until the rat died or cytochrome c returned to baseline. In three survivors, cytochrome c rose slightly to <or=2 microg/ml and returned to baseline within 96 h. In nine nonsurvivors, cytochrome c rose progressively to significantly higher maximal levels [4.6 (SD 2.0) vs. 1.6 (SD 0.3) microg/ml, P = 0.029] and at faster rates [0.7 (SD 0.5) vs. 0.1 (SD 0.1) microg.ml(-1).h(-1), P = 0.046] than in survivors. Plasma cytochrome c may represent a novel in vivo marker of mitochondrial injury after resuscitation from cardiac arrest that relates inversely with survival outcome.
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PMID:Circulating levels of cytochrome c after resuscitation from cardiac arrest: a marker of mitochondrial injury and predictor of survival. 1704 Sep 74

1. Previous experimental studies have shown that dauricine can protect the brain against ischaemic damage, but the underlying mechanisms remain unknown. In the present study, we examined whether dauricine inhibits neuronal apoptosis in the penumbra in a rat model of transient focal cerebral ischaemia. 2. Male Wistar rats underwent a 90 min temporary occlusion of the middle cerebral artery. Dauricine (21, 42 and 84 mg/kg) was administered by intragastric gavage twice a day for 3 days before ischaemia. Rats were killed and brain samples were collected 24 h after ischaemia. Histopathological outcome was evaluated by haematoxylin-eosin staining. Apoptotic changes were evaluated by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) for DNA fragmentation. The mitochondrial pathway was explored using immunohistochemistry for cytochrome c release, caspase 9 and caspase 3 activation, as well as by reverse transcription-polymerase chain reaction for determination of caspase 9 and caspase 3 mRNA expression. 3. Cytochrome c release, activation of caspase 9 and caspase 3 and DNA fragmentation were detected 24 h after ischaemia. Dauricine (42 and 84 mg/kg) pretreatment improved histopathological recovery, diminished DNA fragmentation and reduced cytochrome c release and activation of caspase 9 and caspase 3 in the penumbra at 24 h. 4. These findings suggest that dauricine attenuates apoptosis in the penumbra after transient focal cerebral ischaemia. The infarct-reducing effects of dauricine may be due, in part, to the inhibition of apoptotic cell death via a mitochondrial pathway in the penumbra.
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PMID:Neuroprotective effects of dauricine against apoptosis induced by transient focal cerebral ischaemia in rats via a mitochondrial pathway. 1725 Jun 36

Dequalinium (DQA) has been proposed as a selective antitumoral agent due to its preferential accumulation in mitochondria of cancer cells. Our aim was a better understanding of DQA cytotoxicity. DQA-induced NB4 and K562 cell alterations are initiated within the first 30 min of treatment at a high DQA concentration with a mitochondrial membrane depolarization. Cytochrome c release to cytoplasm, superoxide anion overproduction and ATP depletion in NB4 cells induce, 16 h later, apoptosis by a typical caspase-9/caspase-3-dependent intrinsic pathway. K562 cells were more resistant to the DQA effect than NB4 cells, remaining viable for longer time periods.
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PMID:Dequalinium induces cell death in human leukemia cells by early mitochondrial alterations which enhance ROS production. 1725 Aug 90

C-PC (C-phycocyanin) is a water-soluble biliprotein from the filamentous cyanobacterium Spirulina platensis with potent antioxidant, anti-inflammatory and anticancerous properties. In the present study, the effect of C-PC was tested on the proliferation of doxorubicin-sensitive (S-HepG2) and -resistant (R-HepG2) HCC (hepatocellular carcinoma) cell lines. These studies indicate a 50% decrease in the proliferation of S- and R-HepG2 cells treated with 40 and 50 microM C-PC for 24 h respectively. C-PC also enhanced the sensitivity of R-HepG2 cells to doxorubicin. R-HepG2 cells treated with C-PC showed typical apoptotic features such as membrane blebbing and DNA fragmentation. Flow-cytometric analysis of R-HepG2 cells treated with 10, 25 and 50 microM C-PC for 24 h showed 18.8, 39.72 and 65.64% cells in sub-G(0)/G(1)-phase respectively. Cytochrome c release, decrease in membrane potential, caspase 3 activation and PARP [poly(ADP-ribose) polymerase] cleavage were observed in C-PC-treated R-HepG2 cells. These studies also showed down-regulation of the anti-apoptotic protein Bcl-2 and up-regulation of the pro-apoptotic Bax (Bcl2-associated X-protein) protein in the R-HepG2 cells treated with C-PC. The present study thus demonstrates that C-PC induces apoptosis in R-HepG2 cells and its potential as an anti-HCC agent.
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PMID:Alteration of mitochondrial membrane potential by Spirulina platensis C-phycocyanin induces apoptosis in the doxorubicinresistant human hepatocellular-carcinoma cell line HepG2. 1727 61

Protein oxidation within cells exposed to oxidative free radicals has been reported to occur in an uninhibited manner with both hydroxyl and peroxyl radicals. In contrast, THP-1 cells exposed to peroxyl radicals (ROO(*)) generated by thermo decomposition of the azo compound AAPH showed a distinct lag phase of at least 6 h, during which time no protein oxidation or cell death was observed. Glutathione appears to be the source of the lag phase as cellular levels were observed to rapidly decrease during this period. Removal of glutathione with buthionine sulfoxamine eliminated the lag phase. At the end of the lag phase there was a rapid loss of cellular MTT reducing activity and the appearance of large numbers of propidium iodide/annexin-V staining necrotic cells with only 10% of the cells appearing apoptotic (annexin-V staining only). Cytochrome c was released into the cytoplasm after 12 h of incubation but no increase in caspase-3 activity was found at any time points. We propose that the rapid loss of glutathione caused by the AAPH peroxyl radicals resulted in the loss of caspase activity and the initiation of protein oxidation. The lack of caspase-3 activity appears to have caused the cells to undergo necrosis in response to protein oxidation and other cellular damage.
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PMID:Aqueous peroxyl radical exposure to THP-1 cells causes glutathione loss followed by protein oxidation and cell death without increased caspase-3 activity. 1750 99

We examined whether low dose radiation (LDR) exposure (75 mGy) could increase the therapeutic efficacy of cyclophosphamide (CTX) by comparing the effects of tumor suppression, tumor cell apoptosis, cell cycle and proliferation of bone marrow in vivo. Kunming mice implanted with S(180) sarcoma cells were given 75 mGy whole body gamma-ray radiation exposure and CTX (300 mg/kg) by intraperitoneal injection 36 hours after LDR. Proliferation of bone marrow and tumor cells was analyzed by flow cytometry. Cytochrome c leakage from the tumor was measured by Western-blot. We discovered that tumor growth was significantly reduced in the group exposed to CTX add to LDR. The apoptosis of tumor cells increased significantly after LDR. The tumor cells were arrested in G(1) phase in the groups treated with CTX and CTX + LDR, but cell cycle was more significantly arrested in mice exposed to LDR followed by CTX than in mice exposed only to LDR or CTX chemotherapy. Concentration of bone marrow cells and proliferation index in CTX + LDR mice were higher than those in the untreated mice. LDR or CTX + LDR could induce greater cytochrome c levels and caspase-3 activity in tumors. These results suggest that low dose radiation can enhance the anti-tumor effect of the chemotherapy agent CTX markedly. Furthermore, LDR significantly protects hematopoetic function of the bone marrow, which is of practical significance on adjuvant chemotherapy.
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PMID:Low dose radiation increased the therapeutic efficacy of cyclophosphamide on S(180) sarcoma bearing mice. 1754 41

Acute intoxication with large ammonia doses leads to activation of NMDA receptors in the brain, resulting in oxidative stress and disturbance of mitochondrial function. Altered mitochondrial function is a crucial step in some mechanisms of cellular apoptosis. This study assesses whether ammonia intoxication in vivo leads to induction of apoptotic markers such as permeability transition pore (PTP) formation, caspase-3, and caspase-9 activation, changes in p53 protein, or cytochrome c release. Acute ammonia intoxication did not affect caspase-9 or caspase-3 activities. The mitochondrial membrane potential also remained unaltered in non-synaptic brain mitochondria after injection of ammonia, indicating that ammonia did not induce PTP formation in brain in vivo. The nuclear level of p53 did not change, whereas its cytoplasmic level increased approximately two-fold. In agreement with the theory that translocation of the p53 from cytosol to nuclei is an essential step for induction of apoptosis we did not find apoptotic nuclei in brain of rats injected with ammonia. This supports the idea that ammonia neurotoxicity does not involve apoptosis and points to impaired p53 transfer from cytoplasm to nuclei as a possible preventer of apoptosis. We did not find any release of cytochrome c from mitochondria to cytosol after ammonia injection. Cytochrome c content was significantly reduced (30%) in brain mitochondria from rats injected with ammonia. This decrease may contribute to the reduced state 3 respiration, decreased respiratory control index, and disturbances in the mitochondrial electron transport chain in brain mitochondria from rats injected with ammonia.
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PMID:Acute ammonia neurotoxicity in vivo involves increase in cytoplasmic protein P53 without alterations in other markers of apoptosis. 1755 80

Changes in oxidative stress and apoptotic process were studied during the progression of a compensated hypertrophy to a decompensated heart failure in guinea pigs. Banding of the ascending aorta resulted in heart hypertrophy. At 10 wk, ventricle-to-body weight ratio and thickness of the interventricular septum as well as the left ventricular wall were increased significantly. Although fractional shortening and ejection fraction were decreased, there were no signs of heart failure. Furthermore, there was no increase in wet-to-dry weight ratios for the lungs and liver at this stage. However, at 20 wk, heart failure was characterized by a significant depression in heart function as indicated by a decrease in fractional shortening, and ejection fraction and a lesser increase in wall thickness from diastole to systole. Animals also showed clinical signs of heart failure, and the wet-to-dry weight ratios of the lungs and liver were significantly higher. Cardiomyocyte oxidative stress was significantly higher in the 20-wk aortic-banded group. The ratio of Bax to Bcl-xl showed an increase at 10 wk, and there was a further increase at 20 wk. Mitochondrial membrane potential in the aortic-banded animals was significantly decreased at 10 and 20 wk. Cytochrome c levels were higher in the cytosol compared with the mitochondria, leading to a considerable increase in the expression of p17 subunit of caspase-3. At 20 wk, both early and late stages of apoptosis were observed in isolated cardiomyocytes. It is suggested that an increase in oxidative stress initiates mitochondrial death pathway during the hypertrophic stage, leading to apoptosis and heart failure at a later stage.
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PMID:Activation of apoptotic processes during transition from hypertrophy to heart failure in guinea pigs. 1763 Mar 43

Diepoxybutane (DEB) is the most potent metabolite of the environmental chemical 1,3-butadiene (BD), which is prevalent in petrochemical industrial areas. BD is a known mutagen and human carcinogen, and possesses multi-systems organ toxicity. We recently reported that DEB-induced cell death in TK6 lymphoblasts was due to the occurrence of apoptosis, and not necrosis. In this study, we investigated the molecular mechanisms responsible for DEB-induced apoptosis in these cells. Bax and Bak were found to be over-expressed and activated, and the mitochondrial trans-membrane potential was attenuated in cells undergoing DEB-induced apoptosis. Cytochrome c was depleted from the mitochondria of TK6 cells undergoing apoptosis, and was released into the cytosol in Jurkat T-lymphoblasts exposed to the same concentrations of DEB. Executioner caspase 3 was deduced to be activated by initiator caspase 9. DEB-induced reactive oxygen species (ROS) formation, and the ROS scavenger N-acetyl-L-cysteine effectively blocked DEB-induced apoptosis in TK6 cells. Collectively, these results demonstrate that the mitochondrial apoptotic pathway is activated to mediate DEB-induced apoptosis in human TK6 lymphoblasts. These results further demonstrate that DEB-induced apoptosis is also mediated by the DEB-induced generation of ROS. This is the first report to examine the mechanism of DEB-induced apoptosis in human lymphoblasts.
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PMID:Diepoxybutane activates the mitochondrial apoptotic pathway and mediates apoptosis in human lymphoblasts through oxidative stress. 1769 53

Apoptosis is a physiological mechanism for eliminating malignant cells, including cancer cells, without eliciting damage to normal cells or surrounding tissues. Here, we report that rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid), a major constituent in the rhizome of rhubarb, induced apoptosis of human nasopharyngeal carcinoma (NPC) cells. Rhein induced apoptosis in NPC cells as demonstrated by increased nuclear condensation and DNA fragmentation. Moreover, for the first time in NPC cells it was demonstrated that the pathway involved in rhein-induced apoptosis is caspase-dependent, presumably through the endoplasmic reticulum (ER) stress pathway, as shown by an increase in the levels of glucose-regulated protein 78 (GRP 78), PKR-like ER kinase (PERK), activating transcription factor 6 (A TF6) and CCAA TIenhancer-binding protein homologous protein (CHOP) as well as the activation of caspase-3, -8, -9 and -12. This increased susceptibility to ER stress-induced apoptosis may be due to an increased accumulation of reactive oxygen species (ROS). Rapid accumulation of calcium (Ca2+) and a decrease in the mitochondrial membrane potential (MMP) were also observed. Cytochrome c and apoptosis-inducing factor (AIF) were released upon treatment with rhein. Taken together, these results suggest that ER stress and Ca2+-dependent mitochondrial death pathway may be involved in rhein-induced apoptosis in NPC cells.
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PMID:Rhein induces apoptosis through induction of endoplasmic reticulum stress and Ca2+-dependent mitochondrial death pathway in human nasopharyngeal carcinoma cells. 1797 76


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