Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Oxidative stress induces a variety of cellular responses, including apoptosis, and caspase family proteases are known to be involved in apoptosis.
Caspase-3
(-like) protease activity was examined in Jurkat T cells to investigate the mechanism of apoptosis induced by a thioloxidant, diamide.
Caspase-3
was activated when cells were cultured with 200 microM diamide that induced apoptosis, whereas no
caspase-3
activation was detected with 500 microM diamide that induced necrosis. When apoptosis was induced in cells with exposure to 200 microM diamide, the intracellular
thioredoxin
(
TRX
) levels were maintained and the intracellular generation of reactive oxygen intermediates was marginal. The cytosolic fractions of cytochrome c were increased earlier than the activation of
caspase-3
. In contrast, when cells were exposed to 500 microM diamide, intracellular reactive oxygen intermediate generation was increased and processing of
caspase-3
was not detected despite cytochrome c release, resulting in necrosis.
Caspase-3
activity in cell lysate precultured with anti-Fas Ab was suppressed dose dependently by diamide and restored by thiol-reducing agents, DTT or
TRX
. When cells were precultured with 5 mM of buthionine sulfoximine, an inhibitor of glutathione synthesis, intracellular
TRX
levels were maintained, and as low as 20 microM diamide could induce apoptosis associated with the increase of cytosolic cytochrome c and the activation of
caspase-3
. These results indicate that the activation of
caspase-3
in diamide-induced apoptosis is mediated, at least partly, by cytochrome c release from mitochondria, and the cellular reducing environment maintained by
TRX
, as well as glutathione, is required for
caspase-3
activity to induce apoptosis.
...
PMID:Redox regulation of caspase-3(-like) protease activity: regulatory roles of thioredoxin and cytochrome c. 986 98
Caspases are cysteine proteinases that play a critical role in the execution phase of apoptosis. The active site cysteine residue must be reduced for caspase activity. Thioredoxins are redox proteins that catalyze the reduction of cysteine residues. We have examined the ability of various recombinant human thioredoxins to activate
caspase-3
. The EC(50) for
caspase-3
activation by reduced
thioredoxin
-1 was 2.5 microM, by reduced glutathione 1.0 mM and by dithiothreitol 3.5 mM. A catalytic site redox-inactive mutant
thioredoxin
-1 was almost as active as
thioredoxin
-1 in activating
caspase-3
. Caspase activation was shown to correlate with the number of reduced cysteine residues in the thioredoxins. Reduced insulin and serum albumin were as effective on a molar basis as
thioredoxin
-1 in activating
caspase-3
. Thus,
caspase-3
activation is not a specific effect of thioredoxins but is a property shared by other reduced proteins.
...
PMID:Redox control of caspase-3 activity by thioredoxin and other reduced proteins. 1065 16
Interferons (IFNs) and retinoids are potent tumor growth suppressors. We have shown earlier that the IFN-beta and all-trans retinoic acid combination, but not the single agents, induces death in several tumor cell lines. Employing a genetic approach we have recently identified several Genes associated with Retinoid-IFN induced Mortality (GRIM) that mediate the cell death effect of IFN/RA combination. One of the GRIMs, GRIM-12, was identical to human thioredoxin reductase (TR), an enzyme that controls intracellular redox state. To define the participants of TR mediated death pathway we have examined the role of
thioredoxin
(
Trx
), its downstream substrate, and its influence on IFN/RA-induced death regulation. Inhibition of the
thioredoxin
expression by antisense RNA suppressed cell death. Similarly, a mutant Trx1 lacking the critical cysteine residues blocked cell death. In contrast, overexpression of wildtype
thioredoxin
augmented cell death. This effect of Trx1 was in part due to its ability to augment cell death via caspase-8. The redox inactive Trx1 mutant inhibits the cell death induced by caspase-8 but not
caspase-3
. These studies identify a novel mechanism of cell death regulation by IFN/RA combination involving redox enzymes.
...
PMID:Thioredoxin participates in a cell death pathway induced by interferon and retinoid combination. 1143 33
In retinitis pigmentosa, retinal detachment, age-related macular degeneration, and glaucoma, retinal neuronal cells are damaged by a common mechanism, apoptosis. Because apoptosis is an active process that requires de novo expression of a "death message", this process can be controlled by inhibiting the expression of the "death message". We first studied whether a retinal ischemia-reperfusion model can be used as a model for retinal neuronal apoptosis. In the retinal ischemia-reperfusion injuries, typical features of apoptosis, including TUNEL-positive cells, DNA ladder formation, and ultrastructural features of apoptosis were found. Using the model, systematic research to identify the "death message" was done by DNA microarray analysis. About 200 messages were found to be up- or down-regulated during the process of retinal ischemia-reperfusion. These genes were divided into four groups: (1) transcription factor genes, (2) cell cycle-related genes, (3) reactive oxygen scavenger genes and (4) molecular chaperon genes. The possible roles of such genes in neuronal apoptosis following retinal ischemia-reperfusion injury were studied. In the model, reactive oxygen species produced by reperfusion was found to generate lipid peroxides and induced up-regulation of a transcription factor, c-Jun, that further induced aberrant expression of cell cycle-related genes such as cyclin D1 in amacrine cells. However, because no controlled expression of cell cycle-related genes takes place in retinal neurons, amacrine cells died by a G1 arrest mechanism. On the other hand, horizontal cells never expressed cyclin D1 and the cells were found to die by necrosis. The study revealed a possible mechanism of retinal neuronal apoptosis and it also became apparent that different types of neurons use different "death messages". Furthermore, the possibility that inhibition of a "death message" sometimes induces necrosis rather than apoptosis was shown. This means that we need to try inhibition of the death mechanism upstream rather than downstream. Administration of
thioredoxin
, an endogenous reactive oxygen species that blocks generation of lipid peroxides and thus inhibits the death process upstream, was found to be neuroprotective against retinal ischemia-reperfusion injury. Aberrant expression of c-Jun and cyclin D1 was down-regulated by the treatment. Possible roles of caspases were also studied by using the ischemia-reperfusion injury, RCS rat, and excessive light exposure damage in wild type and caspase-1 deficient mice. Also, application of adeno-associated virus that carries Bcl-xL was tested to find possible neuroprotective effects on RCS rats. Our studies showed that caspase-1 played a more important role in the retinal photoreceptors and
caspase-3
was important in neurons in the inner nuclear layer. Caspase-2 was found to be a major caspase in the retinal ganglion cell layer. In agreement with the findings, caspase-1 deficient mice showed less prominent light damage than wild type mice. Gene therapy by Bcl-xL was effective to protect retinal photoreceptor damage in RCS rats.
...
PMID:[Retinal neuronal cell death: molecular mechanism and neuroprotection]. 1180 59
Thioredoxin-2 (Trx-2) is a mitochondria-specific member of the
thioredoxin
superfamily. Mitochondria have a crucial role in the signal transduction for apoptosis. To investigate the biological significance of Trx-2, we cloned chicken TRX-2 cDNA and generated clones of the conditional Trx-2-deficient cells using chicken B-cell line, DT40. Here we show that TRX-2 is an essential gene and that Trx-2-deficient cells undergo apoptosis upon repression of the TRX-2 transgene, showing an accumulation of intracellular reactive oxygen species (ROS). Cytochrome c is released from mitochondria, while caspase-9 and
caspase-3
, but not caspase-8, are activated upon inhibition of the TRX-2 transgene. In addition, Trx-2 and cytochrome c are co-immunoprecipitated in an in vitro assay. These results suggest that mitochondrial Trx-2 is essential for cell viability, playing a crucial role in the scavenging ROS in mitochondria and regulating the mitochondrial apoptosis signaling pathway.
...
PMID:Thioredoxin-2 (TRX-2) is an essential gene regulating mitochondria-dependent apoptosis. 1192 53
It has been shown that
thioredoxin
(
Trx
) in a reduced form binds to and inhibits apoptosis signal-regulating kinase 1 (ASK1). Apoptotic stimuli such as tumor necrosis factor (TNF) and reactive oxygen species (ROS) activate ASK1 in part by oxidizing
Trx
(forming intramolecular disulfide between C32 and C35) to release
Trx
from ASK1. In the present study, we examined if
Trx
affects ASK1 protein stability and whether the redox activity of
Trx
is critical in regulating ASK1 activity. First, we showed that overexpression of the wild-type
Trx
(Trx-WT) in endothelial cells induced ASK1 ubiquitination and degradation.
Trx
-induced ASK1 ubiquitination/degradation could be blocked by ASK1 activators TNF and TRAF2. We then tested the single-mutation of
Trx
at the catalytic site C32 or C35 (Trx-C32S or Trx-C35S) and the double-mutation (Trx-CS). The results showed that the single mutants (but not Trx-CS) retained the binding activity for ASK1 and the ability to induce ASK1 ubiquitination/degradation. Unlike
Trx
-WT,
Trx
-C32S and
Trx
-C35S mutants constitutively bind to ASK1 even in the presence of hydrogen peroxide in vitro and TNF in vivo. Finally, we showed that the single mutants (not Trx-WT) significantly (n=4 and P<0.05) inhibited ASK1-induced JNK activation,
caspase 3
activity, and apoptosis in TNF/ROS-resistant manner. Our data suggest that association of
Trx
with ASK1 through a single Cysteine (C32 or C35) is necessary and sufficient for
Trx
activity in inducing ASK1 ubiquitination/degradation leading to inhibition of ASK1-induced apoptosis.
...
PMID:Thioredoxin promotes ASK1 ubiquitination and degradation to inhibit ASK1-mediated apoptosis in a redox activity-independent manner. 1208 59
Cellular redox is controlled by the
thioredoxin
(
Trx
) and glutathione (GSH) systems that scavenge harmful intracellular reactive oxygen species (ROS). Oxidative stress also evokes many intracellular events including apoptosis. There are two major pathways through which apoptosis is induced; one involves death receptors and is exemplified by Fas-mediated caspase-8 activation, and another is the stress- or mitochondria-mediated caspase-9 activation pathway. Both pathways converge on
caspase-3
activation, resulting in nuclear degradation and cellular morphological change. Oxidative stress induces cytochrome c release from mitochondria and activation of caspases, p53, and kinases, including apoptosis signal-regulating kinase 1 (ASK1), c-Jun N-terminal kinase, and p38 mitogen-activated protein kinase.
Trx
inhibits apoptosis signaling not only by scavenging intracellular ROS in cooperation with the GSH system, but also by inhibiting the activity of ASK1 and p38. Mitochondria-specific
thioredoxin
(
Trx
-2) and
Trx
peroxidases (peroxiredoxins) are suggested to regulate cytochrome c release from mitochondria, which is a critical early step in the apoptotis-signaling pathway. dATP/ATP and reducing factors including
Trx
determine the manifestation of cell death, apoptosis or necrosis, by regulating the activation process and the activity of redox-sensitive caspases. As mitochondria are the most redox-active organelle and indispensable for cells to initiate or inhibit the apoptosis process, the regulation of mitochondrial function is the central focus in the research field of apoptosis and redox.
...
PMID:Redox control of cell death. 1221 8
Human neuroblastoma cells, SH-SY5Y, contain relatively low levels of
thioredoxin
(
Trx
); thus, they serve favorably as a model for studying oxidative stress-induced apoptosis (Andoh, T., Chock, P. B., and Chiueh, C. C. (2001) J. Biol. Chem. 277, 9655-9660). When these neurotrophic cells were subjected to nonlethal 2-h serum deprivation, their neuronal nitric oxide synthase and
Trx
were up-regulated, and the cells became more tolerant of oxidative stress, indicating that NO may protect cells from serum deprivation-induced apoptosis. Here, the mechanism by which NO exerts its protective effects was investigated. Our results reveal that in SH-SY5Y cells, NO inhibits apoptosis through its ability to activate guanylate cyclase, which in turn activates the cGMP-dependent protein kinase (PKG). The activated PKG is required to protect cells from lipid peroxidation and apoptosis, to inhibit caspase-9 and
caspase-3
activation, and to elevate the levels of
Trx
peroxidase-1 and
Trx
, which subsequently induces the expression of Bcl-2. Furthermore, active PKG promotes the elevation of c-Jun, phosphorylated MAPK/ERK1/2, and c-Myc, consistent with the notion that PKG enhances the expression of
Trx
through its c-Myc-, AP-1-, and PEA3-binding motifs. Elevation of
Trx
and
Trx
peroxidase-1 and Mn(II)-superoxide dismutase would reduce H(2)O(2) and O(2)(), respectively. Thus, the cytoprotective effect of NO in SH-SY5Y cells appears to proceed via the PKG-mediated pathway, and S-nitrosylation of caspases plays a minimal role.
...
PMID:Cyclic GMP-dependent protein kinase regulates the expression of thioredoxin and thioredoxin peroxidase-1 during hormesis in response to oxidative stress-induced apoptosis. 1241 92
Changes in the intracellular reduced/oxidized glutathione ratio (GSH/GSSG) are crucial reduction-oxidation (redox) events that trigger downstream proliferation or death responses. We investigated the molecular mechanisms underlying redox-mediated cell signaling upon an oxidative insult by treating U937 cells with exogenous nonpermeable GSSG. This treatment results in a significant decrease of exofacial cell membrane thiol groups and intracellular decrement of GSH content, owing to its engagement in the formation of mixed disulfides. Changes in
thioredoxin
redox state were also observed, and they may be related to the activation of upstream ASK1 and selective induction of downstream p38 mitogen-activated protein kinase (MAPK) pathway, detectable by phosphorylation of MKK3/6 and p38 MAPK. Moreover, an increase in reactive oxygen species production was detected, and cells were committed to apoptosis along the mitochondrial pathway, evidenced by Bcl-2 down-regulation, cytochome c release from mitochondria, caspase-9 cleavage, and
caspase-3
activation. GSH ethyl ester, a precursor of GSH, by counteracting intracellular mixed disulfide formation, canceled both p38 MAPK activation and GSSG-mediated apoptosis via inhibition of
thioredoxin
oxidation and stabilization of
thioredoxin
/ASK1 complex, whereas, blockage of p38 MAPK by specific inhibitor SB 203580 allowed apoptosis at a very reduced extent. Results suggest that kinase cascade may serve as a primary transducer of cytoplasmic oxidative signals to the nucleus before apoptosis-inducing signals are activated.
...
PMID:Glutathione disulfide induces apoptosis in U937 cells by a redox-mediated p38 MAP kinase pathway. 1242 21
Ten T-cell acute lymphoblastic (T-ALL) CEM cell lines selected for resistance toward methotrexate (CEM/MTX60PGA, CEM/MTX140LV, CEM/MTX1500LV, CEM/MTX5000PGA, CEM/MTXR1, CEM/MTXR2, and CEM/MTXR3), doxorubicin (CEM/ADR5000), vincristine (CEM/VCR1000), or hydroxyurea (CEM/HUR90), respectively, and parental drug-sensitive CCRF-CEM cells were analyzed using comparative genomic hybridization. Most genomic imbalances were not specific for drug resistance, as they were found in both parental and drug-resistant lines. Three aberrations were common to all or most cell lines analyzed: dim(5q35), dim(9p21p24), and enh(20q). We were concerned on those imbalances which were specifically present in drug-resistant but not in drug-sensitive cells. All methotrexate-resistant cell lines were characterized by an enhancement or an amplification of 5q13. The methotrexate resistance-conferring dihydrofolate reductase (DHFR) gene is located at this locus. Gain of DHFR was verified by PCR analyses. CEM/MTX60PGA, CEM/MTX140LV, CEM/MTX1500LV, and CEM/MTX5000PGA showed enh(14q21qter) and CEM/MTX5000PGA amp(5p13p15.2). These two loci harbor the methylenetetrahydrofolate dehydrogenase (MTHFD1) and 5'-methyltetrahdrofolate-homocysteine methyltransferase reductase (MTRR) genes, both of which are involved in folate metabolism. Their gain indicates a role in methotrexate resistance. A loss of 4q35 was found in CEM/MTXR2, CEM/MTXR3, and CEM/ADR5000 where the proapoptotic
caspase-3
gene is located. The
thioredoxin
(
TXN
) locus 9q31 was enhanced in CEM/ADR5000 and CEM/MTX5000PGA cells. 2p22pter was increased in hydroxyurea-resistant CEM/HUR90 cells. Ribonucleotide reductase polypeptide M2 (RRM2), which confers resistance to hydroxyurea, resides at this locus. Other specific genomic imbalances in drug-resistant cell lines were dim(1p36.5), enh(4p), dim(8p22pter), enh(12p13), dim(17p), enh(18q12), enh(21q22.2), dim(21q22.2), and dim(22q13). All genomic imbalances were subjected to hierarchical cluster analysis and clustered image mapping to identify profiles of chromosomal aberrations in the cell lines. The obtained dendrograms allowed separation of imbalances common to all or most cell lines from other more individual aberrations. Furthermore, methotrexate-resistant cell lines clustered together. Our future efforts will be directed toward those imbalances which implicate still unknown candidate drug resistance genes.
...
PMID:Genomic imbalances in drug-resistant T-cell acute lymphoblastic CEM leukemia cell lines. 1248 98
1
2
3
4
5
6
7
8
9
10
Next >>