Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.22.36 (caspase-1)
 6,285 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently shown that dithiocarbamate (DC) disulfides inhibit proteolytic processing of the caspase-3 proenzyme in Jurkat T lymphocytes treated with anti-CD95 (Fas/APO-1) antibody. Because the processing can be accomplished by caspase activity, we investigated the effect of DC disulfides, such as disulfiram (DSF), on active caspases. DSF showed a dose-dependent inhibition was prevented by including dithiothreitol (DTT) in the reaction buffer, thiol-disulfide exchange between inhibitor and target is suggested. Direct interaction of DSF with caspases was confirmed by its inhibition of the purified Ac-DEVD-AMC cleaving protease, caspase-3 (CPP32/apopain). An apparent rate constant (K(app)) for this inhibition was estimated to be 0.45 x 10(3)M(-1)s(-1). DSF was also observed to inhibit the purified Ac-YVAD-AMC cleaving enzyme, caspase-1 (interleukin-1 beta-converting enzyme, ICE), with a K(app) of 2.2 x 10(3) M(-1)s(-1). In this case protein mixed disulfide formation between DSF and caspase-1 was directly demonstrated using 35S-labeled DSF. The physiological disulfide GSSG was also observed to influence the activity of caspases. A glutathione buffer (5 mM) with a GSH:GSSG ratio of 9:1 decreased the Ac-DEVD-AMC cleaving activity in S100 cytosolic extracts by 50% as compared to GSH controls without GSSG. In conclusion, our study shows that caspases are quite sensitive to thiol oxidation and that DSF is a very potent oxidant of caspase protein thiol(s), being 700-fold more potent than glutathione disulfide.
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PMID:Disulfiram is a potent inhibitor of proteases of the caspase family. 943 20

Reactive oxygen species (ROS) are thought to be involved in many forms of programmed cell death. The role of ROS in cell death caused by oxidative glutamate toxicity was studied in an immortalized mouse hippocampal cell line (HT22). The causal relationship between ROS production and glutathione (GSH) levels, gene expression, caspase activity, and cytosolic Ca2+ concentration was examined. An initial 5-10-fold increase in ROS after glutamate addition is temporally correlated with GSH depletion. This early increase is followed by an explosive burst of ROS production to 200-400-fold above control values. The source of this burst is the mitochondrial electron transport chain, while only 5-10% of the maximum ROS production is caused by GSH depletion. Macromolecular synthesis inhibitors as well as Ac-YVAD-cmk, an interleukin 1beta-converting enzyme protease inhibitor, block the late burst of ROS production and protect HT22 cells from glutamate toxicity when added early in the death program. Inhibition of intracellular Ca2+ cycling and the influx of extracellular Ca2+ also blocks maximum ROS production and protects the cells. The conclusion is that GSH depletion is not sufficient to cause the maximal mitochondrial ROS production, and that there is an early requirement for protease activation, changes in gene expression, and a late requirement for Ca2+ mobilization.
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PMID:The regulation of reactive oxygen species production during programmed cell death. 962 98

Glutathione-doxorubicin (GSH-DXR) effectively induced apoptosis in rat hepatoma cells (AH66) at a lower concentration than DXR. After 24 h of drug treatment, DNA fragmentation of the cells was observed at the concentration of 1.0 microM DXR or 0.01 microM GSH-DXR. Increase in caspase-3 activity and DNA fragmentation were observed within 12 h and 15 h after treatment with either drug. Intracellular caspase-3 activity was increased in a dose-dependent manner after treatment with DXR or GSH-DXR, and caspase-3 activity correlated well with the ability to induce DNA fragmentation. When the cells were treated with either DXR or GSH-DXR for only 6 h, apoptotic DNA degradation and caspase-3 activation occurred 24 h after treatment. DNA fragmentation caused by these drugs was prevented completely by simultaneous treatment with the caspase-3 inhibitor, acetyl-Asp-Glu-Val-Asp-aldehyde (DEVD-CHO), at 10 microM. By contrast, DNA fragmentation was not prevented by the caspase-1 inhibitor, acetyl-Tyr-Val-Ala-Asp-aldehyde (YVAD-CHO), at the same concentration as DEVD-CHO, and caspase-1 was not activated at all by the treatment of AH66 cells with both DXR and GSH-DXR. These results demonstrate that DXR and GSH-DXR induce apoptotic DNA fragmentation via caspase-3 activation, but not via caspase-1 activation, and that GSH-DXR enhances the activation of caspase-3 approximately 100-fold more than DXR. Moreover, the findings suggested that an upstream apoptotic signal that can activate caspase-3 is induced within 6 h by treating AH66 cells with the drug.
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PMID:Caspase-3 activation during apoptosis caused by glutathione-doxorubicin conjugate. 1036 Jun 48

Hereditary tyrosinemia type I is the most severe metabolic disease of the tyrosine catabolic pathway mainly affecting the liver. It is caused by deficiency of fumarylacetoacetate hydrolase, which prevents degradation of the toxic metabolite fumarylacetoacetate (FAA). We report here that FAA induces common effects (i.e., cell cycle arrest and apoptosis) in both human (HepG2) and rodent (Chinese hamster V79) cells, effects that seem to be temporally related. Both the antiproliferative and apoptosis-inducing activities of FAA are dose dependent and enhanced by glutathione (GSH) depletion with L-buthionine-(S,R)-sulfoximine (BSO). Short treatment (2 h) with 35 microM FAA/+BSO or 100 microM FAA/-BSO induced a transient cell cycle arrest at the G2/M transition (20% and 37%, respectively) 24 h post-treatment. In cells treated with 100 microM FAA/-BSO, an inactivation, followed by a rapid over-induction of cyclin B-dependent kinase occurred, which peaked 24 h post-treatment. Maximum levels of caspase-1 and caspase-3 activation were detected at 3 h and 32 h, respectively, whereas release of mitochondrial cytochrome c was maximal at 24-32 h post-treatment. The G2/M peak declined 24 h later, concomitantly with the appearance of a sub-G1, apoptotic population showing typical nucleosomal-sized DNA fragmentation and reduced mitochondrial transmembrane potential (Deltapsi(m)). These events were prevented by the general caspase inhibitor z-VAD-fmk, whereas G2/M arrest and subsequent apoptosis were abolished by GSH-monoethylester or N-acetylcysteine. Other tyrosine metabolites, maleylacetoacetate and succinylacetone, had no antiproliferative effects and induced only very low levels of apoptosis. These results suggest a modulator role of GSH in FAA-induced cell cycle disturbance and apoptosis where activation of cyclin B-dependent kinase and caspase-1 are early events preceding mitochondrial cytochrome c release, caspase-3 activation, and Deltapsi(m) loss. -Jorquera, R., Tanguay, R. M. Cyclin B-dependent kinase and caspase-1 activation precedes mitochondrial dysfunction in fumarylacetoacetate-induced apoptosis.
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PMID:Cyclin B-dependent kinase and caspase-1 activation precedes mitochondrial dysfunction in fumarylacetoacetate-induced apoptosis. 1059 76

Chemical-induced oxidative stress to a cell can signal many cellular responses which include proliferation, differentiation, hemeostasis, apoptosis or necrosis. To better understand the underlying molecular mechanisms after exposure to chemicals, we investigated the signal transduction pathways, in particular the mitogen-activated protein kinase (MAPK) pathway and the ICE/Ced-3 protease (caspase) pathway, activated by different agents. Butylated hydroxyanisol (BHA) and its metabolite, t-butyl-hydroquinone (tBHQ), both are well known phenolic antioxidants used in food preservatives, strongly activated c-Jun N-terminal kinase 1 (JNK1) and/or extracellular signal-regulated protein kinase 2 (ERK2) in a dose- and time-dependent fashion. Pretreatment with free radical scavengers N-acetyl-L-cysteine (NAC), glutathione (GSH), or vitamin E, inhibited ERK2 activation and, to a much lesser extent, JNK 1 activation by BHA and tBHQ, implicating the role of oxidative stress. Under conditions where JNK1 and ERK2 were activated, BHA also activated transcription factors nuclear factor kappa B (NF-kappaB), activated-protein-1 (AP-1), and anti-oxidant response element (ARE), leading to induction of genes such as c-jun, and c-fos. At relatively high concentrations, BHA and tBHQ stimulated proteolytic activity of ICE/Ced3 cysteine proteases, and caused apoptosis, which was blocked by pretreatment with NAC. Further increase in concentrations lead to rapid cell death predominantly occurred via necrosis. Some naturally occurring phytochemicals, such as phenylethyl isothiocyanate (PEITC), green tea polyphenols (GTP), and sulfarophane, which have been shown to be potent inducers of Phase II enzymes, also differentially regulated the activities of JNK, ERK, or CPP-32, in a time- and dose-dependent manner. Our data, together with the work of others, enable us to propose a model in which low concentrations of these chemicals (e.g., BHA, PEITC) activate MAPKs leading to induction of gene expression (e.g., c-jun, c-fos, GSI) which may protect the cells against toxic insults and enhance cell survival. At relatively high concentrations, these agents activated both MAPKS, and the ICE/Ced-3 caspase pathway, leading to apoptosis. The exact mechanisms by which MAPK and caspases are activated by these agents are currently unknown, but may involve oxidative modification of glutathione (GSH) and/or protein thiols, and/or generation of secondary messengers, ceramide and calcium, which further activate downstream events. Taken together, our results suggest that chemicals including phenolic antioxidants activate MAPK pathways which may lead to the induction of genes producing protection and survival mechanisms, as well as the ICE/Ced-3 protease pathway, leading to apoptosis. The balancing amongst these pathways may dictate the fate of the cells upon exposure to chemicals.
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PMID:Differential activation of MAPK and ICE/Ced-3 protease in chemical-induced apoptosis. The role of oxidative stress in the regulation of mitogen-activated protein kinases (MAPKs) leading to gene expression and survival or activation of caspases leading to apoptosis. 1267 Dec 99

Oxidative stress has been shown to be associated with apoptosis (programmed cell death) in a number of cell systems. We earlier reported in vitro cultured Spodoptera frugiperda (Sf9) cells as a model system to study oxidative stress induced apoptosis (J Biosciences 24 (1999) 13) and the inhibition of UV-induced apoptosis by the baculovirus antiapoptotic p35 protein that acts as a sink to sequester reactive oxygen species (Proc Natl Acad Sci USA 96 (1999) 4838). We now show that UV-induced apoptosis in Sf9 cells, is preceded by the release of mitochondrial cytochrome c into the cytosol and consequent activation of Sf-caspase-1. The inhibitory effect of different antioxidants including scavengers of oxygen radicals such as butylated hydroxyanisole (BHA), alpha tocopherol acetate, benzoate and reduced-glutathione (GSH) on ultra violet B (UVB)-induced apoptosis in cultured Sf9 cells was assessed. Both, cytochrome c release as well as Sf-caspase-1 activation was inhibited by pre-treatment with antioxidants such as BHA and alpha tocopherol acetate, suggesting that these antioxidants inhibit apoptosis by acting quite upstream in the apoptosis cascade at the mitochondrial level, as well as downstream at the caspase level.
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PMID:Antioxidants prevent UV-induced apoptosis by inhibiting mitochondrial cytochrome c release and caspase activation in Spodoptera frugiperda (Sf9) cells. 1279 76

The parasites of the order kinetoplastidae including Leishmania spp. emerge from most ancient phylogenic branches of unicellular eukaryotic lineages. In their life cycle, topoisomerase I plays a significant role in carrying out vital cellular processes. Camptothecin (CPT), an inhibitor of DNA topoisomerase I, induces programmed cell death (PCD) both in the amastigotes and promastigotes form of L. donovani parasites. CPT-induced cellular dysfunction in L. donovani promastigotes is characterized by several cytoplasmic and nuclear features of apoptosis. CPT inhibits cellular respiration that results in mitochondrial hyperpolarization taking place by oligomycin-sensitive F0-F1 ATPase-like protein in leishmanial cells. During the early phase of activation, there is an increase in reactive oxygen species (ROS) inside cells, which causes subsequent elevation in the level of lipid peroxidation and decrease in reducing equivalents like GSH. Endogenous ROS formation and lipid peroxidation cause eventual loss of mitochondrial membrane potential. Furthermore, cytochrome c is released into the cytosol in a manner independent of involvement of CED3/CPP32 group of proteases and unlike mammalian cells it is insensitive to cyclosporin A. These events are followed by activation of both CED3/CPP32 and ICE group of proteases in PCD of Leishmania. Taken together, our study indicates that different biochemical events leading to apoptosis in leishmanial cells provide information that could be exploited to develop newer potential therapeutic targets.
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PMID:Camptothecin induced mitochondrial dysfunction leading to programmed cell death in unicellular hemoflagellate Leishmania donovani. 1511 64

Glutathione (GSH) and GSH-related enzymes play a great role in protecting organisms from oxidative damage. The GSH level and GSH-related enzymes activities were investigated as well as the growth yield and malonyldialdehyde (MDA) content in the Antarctic ice microalga Chlamydomonas sp. ICE-L exposure to the different cadmium concentration in this paper. The results showed that the higher concentration Cd inhibited the growth of ICE-L significantly and Cd would induce formation of MDA. At the same time, it is clear that GSH level, glutathione peroxidases (GPx) activity and glutathione S-transferases (GST), activity were higher in ICE-L exposed to Cd than the control. But GR activity dropped notably when ICE-L were cultured in the medium containing Cd. Increase of GSH level, GPx and GST activities acclimate to oxidative stress induced by Cd and protect Antarctic ice microalga Chlamydomonas sp. ICE-L from toxicity caused by Cd exposure. These parameters may be used to assess the biological impact of Cd in the Antarctic pole region environment.
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PMID:Effect of Cd on GSH and GSH-related enzymes of Chlamydomonas sp. ICE-L existing in Antarctic ice. 1615 2

The anti-cancer effects and possible mechanisms of the freshwater clam (Corbicula fluminea Muller) and its active compounds (FME) on cell viability in human leukemia HL-60 cells were investigated. This study demonstrated that FME was able to inhibit cell proliferation in a concentration- and time-dependent manner. Treatment with FME caused induction of caspase-2, caspase-3, caspase-6, caspase-8, and caspase-9 activity in a time-dependent manner, but not affect caspase-1 activity; it induced the proteolysis of DNA fragmentation factor (DFF-45) and poly(ADP-ribose) polymerase (PARP). Induction of cell death by FME was completely prevented by a pan-caspase inhibitor, Z-Val-Ala-Asp-fluoromethyl ketone (Z-VAD-FMK) and a caspase-2 inhibitor, Z-Val-Asp-Val-Ala-Asp-FMK (Z-VDVAD-FMK). Furthermore, treatment with FME caused a rapid loss of mitochondrial transmembrane potential, stimulation of generation of reactive oxygen species (ROS), release of mitochondrial cytochrome c into cytosol, and GSH depletion. Anti-oxidants such as N-acetylcysteine, catalase, superoxide dismutase, allopurinol, and pyrrolidine dithiocarbamate, but not diphenylene iodonium, significantly inhibited FME-induced cell death. In addition, the results showed that FME-induced apoptosis was accompanied by up-regulation of Bax and Bad, and down-regulation of Bcl-2 and Bcl-XL. Taken together, induction of apoptosis on HL-60 cells by FME was mainly associated with ROS production, GSH depletion, mitochondrial dysfunction, and caspase activation.
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PMID:Apoptosis-inducing active components from Corbicula fluminea through activation of caspase-2 and production of reactive oxygen species in human leukemia HL-60 cells. 1654 98

Cellular adaptation to different stresses related to survival and function has been demonstrated in several cell types. Anthrax lethal toxin (LeTx) induces rapid cell death, termed "pyroptosis," by activating NLRP1b/caspase-1 in murine macrophages. We and others (S. D. Ha et al., J. Biol. Chem. 282:26275-26283, 2007; I. I. Salles et al., Proc. Natl. Acad. Sci. U. S. A. 100:12426 -12431, 2003) have shown that RAW264.7 cells preexposed to sublethal doses of LeTx become resistant to subsequent high cytolytic doses of LeTx, termed toxin-induced resistance (TIR). To date, the cellular mechanisms of pyroptosis and TIR are largely unknown. We found that LeTx caused NLRP1b/caspase-1-dependent mitochondrial dysfunction, including hyperpolarization and generation of reactive oxygen species, which was distinct from that induced by stimuli such as NLRP3-activating ATP. In TIR cells, these mitochondrial events were not detected, although caspase-1 was activated, in response to LeTx. We identified that downregulation of the late endosomal cholesterol-transferring protein MLN64 in TIR cells was involved in TIR. The downregulation of MLN64 in TIR cells was at least in part due to DNA methyltransferase 1-mediated DNA methylation. In wild-type RAW264.7 cells and primary bone marrow-derived macrophages, LeTx caused NLRP1b/caspase-1-dependent mitochondrial translocation of MLN64, resulting in cholesterol enrichment, membrane hyperpolarization, reactive oxygen species (ROS) generation, and depletion of free glutathione (GSH). This study demonstrates for the first time that MLN64 plays a key role in LeTx/caspase-1-induced mitochondrial dysfunction.
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PMID:Cellular adaptation to anthrax lethal toxin-induced mitochondrial cholesterol enrichment, hyperpolarization, and reactive oxygen species generation through downregulating MLN64 in macrophages. 2302 46


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