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)

We tested the hypothesis that combined use of trophic factors and caspase inhibitors increases brain resistance to ischaemia in mice. Intracerebroventricular administration of bFGF (>10 ng) 30 min after MCA occlusion decreased infarct size and neurological deficit in a dose-dependent manner following 2 h ischemia and reperfusion (20 h). Combined administration of the subthreshold doses of bFGF (3 ng) and caspase inhibitors (z-VAD.FMK, 27 ng or z-DEVD.FMK, 80 mg) reduced infarct volume by 60%, and reduced neurological deficit. Treatment with a subthreshold dose of bFGF (3 ng) extended the therapeutic window for z-DEVD.FMK (480 ng) from 1 to 3 h after reperfusion. Caspase-3 activity in the ischaemic brain was increased 30 min and 2 h after reperfusion but, was significantly reduced in bFGF-treated animals by 29 and 16%, respectively. Caspase-3 activity was not reduced by a direct bFGF effect because addition of bFGF (10 nM - 2 microM) did not decrease recombinant caspase-3 activity, in vitro. Our data show that combining caspase inhibitors and bFGF lengthens the treatment window for the second treatment, plus lowers the dosage requirements for neuroprotection. These findings are important because low doses of caspase inhibitors or bFGF reduce the possibility of side effects plus extend the short treatment window for ischaemic stroke.
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PMID:Synergistic protective effect of caspase inhibitors and bFGF against brain injury induced by transient focal ischaemia. 1137 50

The mitogen-activated protein kinase (MAPK) cascades are thought to be important mediators in the transduction of extracellular signals into cellular responses. The p38 kinase, a member of the MAPK superfamily, is activated by a wide variety of extracellular stimuli and has been implicated in neuronal apoptosis induced by glutamate. In this study we have examined the role of p38 kinase in the potassium deprivation model of apoptosis in rat cerebellar granule neurons (CGN). An increase in p38 kinase activity was observed with a 15-minute potassium deprivation when compared to the basal level. We also found that SB203580 and PD169316, specific p38 kinase inhibitors, significantly attenuated apoptosis in potassium-deprived cells in a dose dependent manner. A decrease in caspase-3 mediated DEVD-MCA, substrate hydrolysis and the appearance of the 120 kDa-spectrin breakdown product in cells treated with SB203580 further suggests that the p38 kinase acts upstream of caspase-3 in the apoptosis cascade. The data provides evidence for an essential role of p38 kinase in mediating apoptotic cell death in CGN and the inhibition of p38 kinase mimics the suppression of apoptosis provided by natural survival signals.
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PMID:Inhibition of p38 kinase mimics survival signal-linked protection against apoptosis in rat cerebellar granule neurons. 1154 39

In contrast to the autoprocessing of caspase-9, little is known about the biological significance of caspase-9 processing by caspase-3 via a feedback loop in vivo. We prepared antisera against mouse caspase-9 cleavage sites so that only the activated form of mouse caspase-9 was recognized. Using these antisera and caspase-9- and caspase-3-deficient mouse embryonic fibroblasts, we demonstrated that mouse caspase-9 is initially autoprocessed at D(353) and D(368) at low levels during staurosporine-induced apoptosis, whereupon the D(368) and D(168) sites are preferentially processed over D(353) by activated caspase-3 as part of a feedback amplification loop. Ac-DEVD-MCA (caspase-3-like) and Ac-LEHD-MCA (caspase-9-like) cleavage activities clearly showed that caspase-9 autoprocessing was necessary for the activation of caspase-3, whereas full activation of caspase-3 and caspase-9 was achieved only through the feedback amplification loop. This feedback amplification loop also played a predominant role during programmed cell death of dorsal root ganglia neurons at mouse embryonic day 11.5.
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PMID:Caspase-9 processing by caspase-3 via a feedback amplification loop in vivo. 1155 85

2-tert-Butyl-4-hydroquinone (TBHQ), a phenolic antioxidant used as a food additive, and its metabolite 2-tert-butyl-1,4-benzoquinone (TBQ) were both cytotoxic in human monocytic leukemia U937 cells, TBQ being the more strongly cytotoxic. Both compounds induced caspase activity towards DEVD-MCA as a substrate and the cleavage of poly(ADP-ribose) polymerase in cells. Enzyme activities of caspase-3,-7,-6 and -9 seemed to be induced, and procaspases-3 and-7 were processed to active forms in cells treated with TBHQ and TBQ. They induced nuclear condensation and fragmentation in some cells. Electron microscopic examination revealed severe disruption of mitochondrial structure and the formation of intracellular vacuoles. Morphological changes were more marked in the cells treated with TBHQ than TBQ. Mitochondrial transmembrane potential was disrupted. Cytochrome c was released from mitochondria to cytosol and ATP level was moderately decreased by the treatment of cells with these chemicals. Cellular glutathione (GSH) appeared to contribute to defense against cell death induced by TBQ, but its contribution was not marked in the case of TBHQ. TBHQ and TBQ exhibited the apoptotic features in various assays, but the mode of cell death may not be defined as a typical apoptosis or necrosis.
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PMID:Cell death induced by the phenolic antioxidant tert-butylhydroquinone and its metabolite tert-butylquinone in human monocytic leukemia U937 cells. 1265 21

Caspase-3-deficient 129/Sv mice show hyperplasia of the brain at embryonic (E) day 10.5-12.5, but caspase-3-deficient C57L/B6 mice do not. We examined the relationship between activation of caspase-3 and programmed cell death (PCD) during forebrain development of various mouse strains (129/Sv, ICR, C57L/B6, and CBA) using terminal deoxytransferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) and immunostaining with antiserum against the caspase-3 (anti-m3D175) cleavage site. A number of anti-m3D175 positive cells and TUNEL positive cells were detected in the ventral side of the forebrain of 129/Sv and ICR mice at E8.5-9 but not in C57L/B6 and CBA mice. Ac-DEVD-MCA cleavage activity, a caspase-3-like activity, also suggests the preferential activation of caspase-3 in the ventral forebrain of ICR mice but not in C57L/B6 mice. Developmental changes of TUNEL and anti-m3D175 reactivities were essentially similar during brain morphogenesis of ICR and 129/Sv mice. The number of TUNEL/anti-m3D175 positive cells decreased in the neuroepithelium of the ventral forebrain at E9.5 before generation of the medial ganglionic eminence (MGE). TUNEL and/or anti-m3D175 reactivity was slightly detectable in the MGE at E10.5, from which neuroprogenitor cells follow a tangential migratory route to the cortex. Activation of caspase-9 was also immunohistochemically detected in the ventral forebrain at E8.5-9, suggesting that activation of caspase-3 and caspase-9 occurs in the PCD of this region. Thus, it is likely that decreased cell death in the ventral forebrain of caspase-3- and caspase-9-deficient 129/Sv mice increases the number of neuroprogenitor cells in the MGE, leading to hyperplasia of the forebrain.
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PMID:Region of caspase-3 activation and programmed cell death in the early development of the mouse forebrain. 1460 64

The death of a cell via apoptosis is characterized by morphological changes including cell shrinkage and nuclear condensation. Intracellularly, proteases, including caspases, are activated. In the present article we have compared the ability of three different neurotoxic agents to induce caspase activity in cerebellar granule cells (CGC). These compounds are the microtubule-disrupting agent colchicine and the oxidative stress-inducing agents hydrogen peroxide and methylmercury (MeHg). We have previously shown that each of these agents causes nuclear changes that are consistent with apoptosis, i.e., induction of chromatin condensation and DNA cleavage into fragments of regular size (700, 300 and 50 kbp). However, only colchicine causes a large increase in caspase activity, as monitored by the ability of whole cell extracts to cleave the synthetic caspase substrate DEVD-MCA. In contrast, MeHg and hydrogen peroxide do not induce any significant increase of DEVDase activity as compared to control cells. Immunocytochemistry confirms that active caspase-3 is abundant only in colchicine-exposed cells. In agreement with these findings, the pan-caspase inhibitor, z-VAD-fmk, is efficient in protecting CGC against colchicine, but not against hydrogen peroxide or MeHg. These data suggest that in CGC the activation of caspases is not always required to induce morphological changes and pattern of DNA fragmentation consistent with apoptosis.
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PMID:Apoptotic morphology does not always require caspase activity in rat cerebellar granule neurons. 1471 61

Stimulant-induced viability of neutrophils, nuclear-fragmentation, increase in intracellular calcium ([Ca2+]i), expression of annexin V on neutrophils and proteolysis of a fluorogenic peptide substrate Ac-DEVD-MCA (acetyl Asp-Glu-Val-Asp alpha-[4-methyl-coumaryl-7-amide]) by neutrophil lysates from five normal calves and three calves with leucocyte adhesion deficiency were determined to evaluate the apoptosis of normal and CD18-deficient neutrophils. Viability was markedly decreased in control neutrophils stimulated with opsonized zymosan (OPZ), compared to CD18-deficient neutrophils at 37 degrees C after incubation periods of 6 and 24 hours. The rate of apoptosis of control neutrophils stimulated with OPZ increased significantly depending on the incubation time, whereas no apparent increase in apoptosis was found in CD18-deficient neutrophils under the same conditions. Aggregated bovine (Agg) IgG-induced apoptosis of control neutrophils was not significantly different from that of CD18-deficient neutrophils. The expression of annexin V on OPZ-stimulated control neutrophils was greater than that of unstimulated ones 6 h after stimulation. No apparent increase in annexin V expression on CD18-deficient neutrophils was found with OPZ stimulation. A delay in apoptosis was demonstrated in CD18-deficient bovine neutrophils and this appeared to be closely associated with lowered signalling via [Ca2+]i, diminished annexin V expression on the cell surface, and decreased caspase 3 activity in lysates.
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PMID:Decreased apoptosis of beta 2- integrin-deficient bovine neutrophils. 1498 92

A phenolic antioxidant 3-tert-butyl-4-hydroxyanisole (BHA) is a widely used food additive. BHA had cytotoxicity in human monocytic leukemia U937 cells. BHA at 0.75 mM caused nuclear condensation and fragmentation, structural damage in mitochondria, decrease in mitochondrial transmembrane potential, and internucleosomal DNA cleavage. It induced the activities of caspase-3 and/or -7, -6, -8 and -9, especially high when DEVD-MCA was the substrate (caspase-3 and/or -7). DEVDase activity increased in time- and dose-dependent manner and high activity was observed in lysates of cells treated for 3 h at 0.75 mM. Addition of GSH (reduced glutathione) during the treatment of cells with BHA inhibited the induction of DEVDase activity, and the intracellular GSH level decreased as the concentration of BHA was raised. Intracellular ATP levels decreased in time- and dose-dependent manner when the cells were treated with BHA in the presence or absence of glucose. Enzyme activities involved in the respiratory chain were assayed with the mitochondrial fraction prepared from U937 cells. BHA distinctly inhibited NADH-ubiquinone oxidoreductase (complex I) and cytochrome c oxidase (complex IV) at low concentrations. Succinate-ubiquinone oxidoreductase (complex II) was also inhibited, but to somewhat less extent. Without mitochondrial enzymes, BHA stimulated the ubiquinol-dependent reduction of cytochrome c (complex III), but it might have some detrimental effects on the mitochondrial enzyme reaction of complex III. The inhibition of mitochondrial oxidative phosphorylation might corroborate the mechanistic evidence for apoptosis of leukemia cells by BHA. Cell death induced by BHA is primarily ascribable to apoptosis.
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PMID:Molecular mechanism of cell death induced by the antioxidant tert-butylhydroxyanisole in human monocytic leukemia U937 cells. 1499 91

The chlorohydroxyfuranones (CHFs) MX [3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone], MCA [3,4-dichloro-5-hydroxy-2(5H)-furanone], CMCF [3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone], and MCF [3-chloro-4-methyl-5-hydroxy-2(5H)-furanone] are genotoxic disinfection by-products of drinking water chlorination. MX, MCA, and MCF also promote foci formation in the two-stage cell transformation assay. The cellular mechanisms underlying this apparent promotional effect are not known. In the present study, the effects of MX, MCA, CMCF, and MCF on gap junctional intercellular communication (GJIC) were measured in BALB/c 3T3 cells using the scrape loading dye technique. The effect of MX on apoptosis in the same cell line was explored by assaying caspase-3-like protease activity. All the four CHFs inhibited GJIC after 30 min exposure in a dose-dependent fashion but there was a marked difference in the ranges of their active concentrations. MX was almost as potent an inhibitor of GJIC (inhibition at nanomolar concentrations) as 12-O-tetradecanoylphorbol-13-acetate (TPA) (positive control), while MCA was 10 times weaker, CMCF 10,000 times weaker, and MCF 20,000 times weaker than MX. After prolonged exposure periods (up to 6 h), GJIC recovered somewhat upon MX and MCA exposures, the inhibition of GJIC by MCF remained constant but CMCF showed an irreversible increasing inhibitory effect. MX caused apoptosis as a "window" effect at concentrations 2000-4000-fold higher than those needed to inhibit GJIC. The results indicate that MX is a potent inhibitor of GJIC in BALB/c 3T3 cells and this inhibition might be one mechanism by which MX can promote malignant foci formation. MCA also has a specific potential to inhibit GJIC whereas MCF and CMCF affected GJIC at concentrations, similar to those evoking genotoxicity in vitro.
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PMID:Potent inhibition of gap junctional intercellular communication by 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) in BALB/c 3T3 cells. 1526 88

Many human proteins have homopolymeric amino acid (HPAA) tracts, although the physiological significance or cellular effects of their presence is poorly understood. We previously reported that 20 kinds of HPAAs show characteristic intracellular localization and that among those, hydrophobic HPAAs aggregate strongly and form high molecular weight proteins when expressed in cultured cells. In this study, we investigated the cytotoxicity of 20 kinds of HPAAs. HPAA tracts of approximately 30 residues fused to the C-terminus of YFP were expressed in COS-7 cells. Cells expressing homopolymeric-Cys, -Ile, -Leu, and -Val showed low viability in Trypan Blue assay. Caspase-3 activity, which is usually upregulated in dying cells, was determined by measuring the cleavage of the peptide substrate Ac-DEVD-MCA and by detecting the cleaved active form of the caspase-3 by Western blotting. The activity of caspase-3 was drastically elevated in cells expressing those HPAAs which showed low viability in Trypan Blue assay. Interestingly, it was found that there is a correlation between the hydrophobicity of a single amino acid and the cytotoxicity of the corresponding HPAA as a homopolymer. These results indicate that the hydrophobicity of HPAAs may cause cytotoxicity.
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PMID:Comparative analysis of the cytotoxicity of homopolymeric amino acids. 1576 94


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