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Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Children with congenital homozygous deficiency of purine nucleoside phosphorylase (PNP) have abnormalities in purine metabolism that result in T-cell selective immune deficiency. The mechanism of action for cell death has been attributed to intracellular accumulation of dGTP, a potent inhibitor of ribonucleotide reductase and subsequently DNA synthesis, in thymocytes and T-cells but not B-cells. However, the mode of cell death has not been determined to be either necrosis or apoptosis. To examine the involvement of apoptosis in T-cells following PNP inhibition, MOLT-4 cells, a human T cell leukemia cell line, were co-treated with the PNP inhibitor, CI-1000 (2-amino 3,5-dihydro-7-(3-thienylmethyl)-4H-pyrrolo[3,2-d]-pyrimidin-4-one HCl), and 2'-deoxyguanosine (dGuo) which resulted in a concentration-dependent loss of cell viability (trypan blue) and inhibition of tritiated thymidine ([3H]-TdR) uptake. Staining of cells with the DNA dye Hoechst 33,258 showed nuclear morphology characteristic of apoptosis. Western blots (24 h lysates) were probed with antibodies against several proteins implicated in apoptosis. Anti-PARP revealed the presence of an 85 kD PARP breakdown product while, anti-
alpha-spectrin
revealed the accumulation a 120 kD breakdown product, both suggestive of CPP32 cleavage (
caspase-3
; an ICE-like cysteine protease). Western blots also detected the loss of the intact 32 kD
caspase-3
isoform, a biochemical event associated with
caspase-3
activation. Corresponding fluorometric activity assays detected a marked increase in
caspase-3
-like activity using the substrate Ac-DEVD-MCA. Lastly, a pan caspase inhibitor (Z-D-DCB) and 2'-deoxycytidine (dCyd), which is known to prevent dGTP accumulation following PNP inhibition, were able to prevent cell death and all indicators of
caspase-3
-like activity in MOLT-4 cells co-treated with dGuo and CI-1000. In summary, we provided several lines of evidence for the role of apoptosis and the contribution of
caspase-3
-like proteases in T-cell death following PNP inhibition.
...
PMID:A purine nucleoside phosphorylase (PNP) inhibitor induces apoptosis via caspase-3-like protease activity in MOLT-4 T cells. 940 42
Caspase 3-like proteases are key executioners in mammalian apoptosis, and the calpain family of cysteine proteases has also been implicated as an effector of the apoptotic cascade. However, the influence of upstream events on calpain/caspase activation and the role of calpain/caspase activation on subsequent downstream events are poorly understood. This investigation examined the temporal profile of apoptosis-related events after staurosporine-induced apoptosis in mixed glial-neuronal septo-hippocampal cell cultures. Following 3 hr exposure to staurosporine (0.5 microM), calpain and
caspase 3
-like proteases processed
alpha-spectrin
to their signature proteolytic fragments prior to endonuclease-mediated DNA fragmentation (not evident until 6 hr), indicating that endonuclease activation is downstream from calpain/caspase activation. Cycloheximide, a general protein synthesis inhibitor, completely prevented processing of
alpha-spectrin
by calpains and
caspase 3
-like proteases, DNA fragmentation and cell death, indicating that de novo protein synthesis is an upstream event necessary for activation of calpains and
caspase 3
-like proteases. Calpain inhibitor II and the pan-caspase inhibitor Z-D-DCB each inhibited their respective protease-specific processing of
alpha-spectrin
and attenuated endonuclease DNA fragmentation and cell death. Thus, activation of calpains and
caspase 3
-like proteases is an early event in staurosporine-induced apoptosis, and synthesis of, as yet, unknown protein(s) is necessary for their activation.
...
PMID:Temporal relationships between de novo protein synthesis, calpain and caspase 3-like protease activation, and DNA fragmentation during apoptosis in septo-hippocampal cultures. 963 7
We have previously demonstrated cleavage of
alpha-spectrin
by
caspase-3
and calpain during apoptosis in SH-SY5Y neuroblastoma cells (Nath, R., Raser, K. J., Stafford, D., Hajimohammadreza, I., Posner, A., Allen, H., Talanian, R. V., Yuen, P., Gilbertsen, R. B., and Wang, K. K. (1996) Biochem. J. 319, 683-690). We demonstrate here that calcium/calmodulin-dependent protein kinase IV (CaMK IV) is cleaved during apoptosis by
caspase-3
and calpain. We challenged SH-SY5Y cells with the pro-apoptotic agent thapsigargin. Western blot analysis revealed major CaMK IV breakdown products of 40, 38, and 33 kDa. Digestion of control SH-SY5Y lysate with purified
caspase-3
produced a 38-kDa CaMK IV fragment; digestion with purified calpain produced a major fragment of 40 kDa. Pretreatment with carbobenzoxy-Asp-CH2OC(O)-2,6-dichlorobenzene or Z-Val-Ala-Asp-fluoromethylketone was able to block the
caspase-3
-mediated production of the 38-kDa fragment both in situ and in vitro. Calpain inhibitor II similarly blocked formation of the calpain-mediated 40-kDa fragment both in situ and in vitro. Digestion of recombinant CaMK IV by other caspase family members revealed that only
caspase-3
produces a fragmentation pattern consistent to that seen in situ. The major
caspase-3
and calpain cleavage sites are respectively identified as PAPD176*A and CG201*A, both within the CaMK IV catalytic domain. Furthermore, calmodulin-stimulated protein kinase activity decreases within 6 h in thapsigargin-treated SH-SY5Y. The loss of activity precedes cell death.
...
PMID:Calcium/calmodulin-dependent protein kinase IV is cleaved by caspase-3 and calpain in SH-SY5Y human neuroblastoma cells undergoing apoptosis. 968 36
Activity of calpains and
caspase-3
inferred from proteolysis of the cytoskeletal protein
alpha-spectrin
into signature spectrin breakdown products (SBDPs) was used to provide the first systematic and simultaneous comparison of changes in activity of these two families of cysteine proteases after traumatic brain injury (TBI) in rats. Distinct regional and temporal patterns of calpain/
caspase-3
processing of
alpha-spectrin
were observed in brain regions ipsilateral to the site of injury after TBI, including large increases of 145 kDa calpain-mediated SBDP in cortex (up to 30-fold), and enduring increases (up to 2 weeks) of 145 kDa SBDP in hippocampus and thalamus. By contrast, 120 kDa
caspase-3
-mediated SBDP was absent in cortex and showed up to a 2-fold increase in hippocampus and striatum at early (hours) after TBI. Future studies will clarify the pathological significance of large regional differences in activation of calpain and
caspase-3
proteases after TBI.
...
PMID:Regional calpain and caspase-3 proteolysis of alpha-spectrin after traumatic brain injury. 972 10
The caspase family of proteases has previously been implicated in the biochemical cascade leading to apoptotic cell death. Recently
caspase-3
was reported to be cleaved into its catalytically active subunits (17 and 13 kDa) following phytohemagglutinin (PHA) activation of peripheral blood mononuclear cells (C. Miossec et al., J. Biol. Chem. 272, 13459-13462). More recently, J. M. Zapata and colleagues (J. Biol. Chem. 273, 6916-6920, 1998), however, proposed that
caspase-3
activity detected during T-cell activation was due to a methodological artifact related to the composition of the cell lysis buffer. Here we show that in PHA-activated Jurkat T-cells using the recommended lysis buffer detailed by Zapata et al., a
caspase-3
-like protease is activated and is accompanied by cleavage of PARP and
alpha-spectrin
into cleavage products suggestive of
caspase-3
proteolytic activation. LDH release did not increase following PHA stimulation in this paradigm. Two caspase inhibitors, carbobenzoxy-Asp-CH2OC(O)-2,6-dichlorobenzene (Z-D-DCB) and acetyl-Asp-Glu-Val-Asp-CHO, blocked IL-2 release in a dose-dependent manner.
Caspase-3
-like protease-generated PARP and
alpha-spectrin
breakdown product formation was also reduced by Z-D-DCB. In addition, Jurkat T-cells costimulated with anti-CD3 plus anti-CD28 produced significant levels of IL-2 that were also blocked by these caspase inhibitors. Importantly, IL-2 was determined in cell culture supernatants, thus avoiding a cell lysis step that might have enabled activation of
caspase-3
by granzyme B. Collectively, these data support the role of
caspase-3
-like protease activity in Jurkat T-cell activation and demonstrate that
caspase-3
like activity is necessary for IL-2 release in PHA-activated and anti-CD3/anti-CD28 costimulated Jurkat T-cells.
...
PMID:Caspase-3-like activity is necessary for IL-2 release in activated Jurkat T-cells. 977 Mar 73
Maitotoxin is a potent toxin that activates voltage and receptor-mediated Ca2+ channels, resulting in Ca2+ overload and rapid cell death. We report that maitotoxin-induced cell death is associated with activation of calpain but not
caspase-3
proteases in septo-hippocampal cell cultures. Calpain and
caspase-3
activation were examined by accumulation of protease-specific breakdown products to
alpha-spectrin
. Cell death manifested exclusively necrotic-like characteristics including round, shrunken nuclei, even distribution of chromatin, absence of DNA fragmentation and failure of protein synthesis inhibition to reduce cell death. Necrotic cell death was observed in neurons and astroglia. Calpain inhibitor II inhibited calpain-specific processing of
alpha-spectrin
and significantly reduced cell death. The pan-caspase inhibitor, Z-D-DCB, nominally attenuated cell death. Results suggest that: (1) calpain, but not
caspase-3
, is activated as a result of maitotoxin-induced Ca2+ influx; (2) necrotic cell death caused by maitotoxin exposure is partially mediated by calpain activation; (3) maitotoxin is a useful tool to investigate pathological mechanisms of necrosis.
...
PMID:Maitotoxin induces calpain but not caspase-3 activation and necrotic cell death in primary septo-hippocampal cultures. 1021 11
Unilateral injection of 50 nmol of N-methyl-D-aspartate (NMDA) into the left posterior striatum of 7 day-old rat pups induces massive neuronal loss in the ipsilateral hemisphere in 5 days. In this model of excitotoxicity, the form of neuronal death (necrosis vs apoptosis) has not been clearly addressed. Here we report evidence of DNA laddering in the ipsilateral hemisphere 24 h after the NMDA injection. Activation of apoptosis-linked caspase(s) was also identified, as evidenced by (i) the formation of caspase-produced 120 kDa
alpha-spectrin
breakdown product (SBDP120) and (ii) increase in hydrolysis of
caspase-3
substrate acetyl-DEVD-7-amido-4-methylcoumarin in the homogenate from the ipsilateral hemisphere. Lastly, we note that i.p. injection (100 mg/kg) of a pan caspase inhibitor Z-D-DCB attenuates the levels of SBDP120. Our results suggest the presence of caspase-activation in this rat pup model of NMDA toxicity.
...
PMID:Activation of apoptosis-linked caspase(s) in NMDA-injured brains in neonatal rats. 1067 75
Studies examined the phenotypic characteristics of glutamate-induced cell death and their relationship to calpain and
caspase-3
activation. Cell viability was assessed by fluorescein diacetate and propidium iodide staining and lactate dehydrogenase release. Calpain and
caspase-3
activity was inferred from signature proteolytic fragmentation of
alpha-spectrin
. Characterization of cell death phenotypes was assessed by Hoechst 33258 and DNA fragmentation assays. Exposure of septohippocampal cultures to 1.0, 2.0, and 4.0 mmol/L glutamate induced a dose-dependent cell death with an LD50 of 2.0 mmol/L glutamate after 24 hours of incubation. Glutamate treatment induced cell death in neurons and astroglia and produced morphological alterations that differed from necrotic or apoptotic changes observed after maitotoxin or staurosporine exposure, respectively. After glutamate treatment, cell nuclei were enlarged and eccentrically shaped, and aggregated chromatin appeared in a diffusely speckled pattern. Furthermore, no dose of glutamate produced evidence of internucleosomal DNA fragmentation. Incubation with varying doses of glutamate produced calpain and
caspase-3
activation. Calpain inhibitor II (N-acetyl-Leu-Leu-methionyl) provided protection only with a narrow dose range, whereas carbobenzoxy-Asp-CH2-OC(O)-2,6-dichlorobenzene (Z-D-DCB; pan-caspase inhibitor) and MK-801 (N-methyl-D-aspartate receptor antagonist) were potently effective across a wider dose range. Cycloheximide did not reduce cell death or protease activation.
...
PMID:Novel characteristics of glutamate-induced cell death in primary septohippocampal cultures: relationship to calpain and caspase-3 protease activation. 1072 20
Axonal injury is a feature of traumatic brain injury (TBI) contributing to both morbidity and mortality. The traumatic axon injury (TAI) results from focal perturbations of the axolemma, allowing for calcium influx triggering local intraaxonal cytoskeletal and mitochondrial damage. This mitochondrial damage has been posited to cause local bioenergetic failure, leading to axonal failure and disconnection; however, this mitochondrial damage may also lead to the release of cytochrome c (cyto-c), which then activates caspases with significant adverse intraaxonal consequences. In the current communication, we examine this possibility. Rats were subjected to TBI, perfused with aldehydes at 15-360 min after injury, and processed for light microscopic (LM) and electron microscopic (EM) single-labeling immunohistochemistry to detect extramitochondrially localized cytochrome c (cyto-c) and the signature protein of
caspase-3
activation (120 kDa breakdown product of
alpha-spectrin
) in TAI. Combinations of double-labeling fluorescent immunohistochemistry (D-FIHC) were also used to demonstrate colocalization of calpain activation with cyto-c release and
caspase-3
-induction. In foci of TAI qualitative-quantitative LM demonstrated a parallel, significant increase in cyto-c release and
caspase-3
activation over time after injury. EM analysis demonstrated that cyto-c and
caspase-3
immunoreactivity were associated with mitochondrial swelling-disruption in sites of TAI. Furthermore, D-IFHC revealed a colocalization of calpain activation, cyto-c release, and
caspase-3
induction in these foci, which also revealed progressive TAI. The results demonstrate that cyto-c and
caspase-3
participate in the terminal processes of TAI. This suggests that those factors that play a role in the apoptosis in the neuronal soma are also major contributors to the demise of the axonal appendage.
...
PMID:Cytochrome c release and caspase activation in traumatic axonal injury. 1075 34
Traumatic brain injury (TBI) results in numerous central and systemic responses that complicate interpretation of the effects of the primary mechanical trauma. For this reason, several in vitro models of mechanical cell injury have recently been developed that allow more precise control over intra- and extracellular environments than is possible in vivo. Although we recently reported that calpain and
caspase-3
proteases are activated after TBI in rats, the role of calpain and/or
caspase-3
has not been examined in any in vitro model of mechanical cell injury. In this investigation, varying magnitudes of rapid mechanical cell stretch were used to examine processing of the cytoskeletal protein
alpha-spectrin
(280 kDa) to a signature 145-kDa fragment by calpain and to the apoptotic-linked 120-kDa fragment by
caspase-3
in septo-hippocampal cell cultures. Additionally, effects of stretch injury on cell viability and morphology were assayed. One hour after injury, maximal release of cytosolic lactate dehydrogenase and nuclear propidium iodide uptake were associated with peak accumulations of the calpain-specific 145-kDa fragment to
alpha-spectrin
at each injury level. The acute period of calpain activation (1-6 h) was associated with subpopulations of nuclear morphological alterations that appeared necrotic (hyperchromatism) or apoptotic (condensed, shrunken nuclei). In contrast,
caspase-3
processing of
alpha-spectrin
to the apoptotic-linked 120-kDa fragment was only detected 24 h after moderate, but not mild or severe injury. The period of
caspase-3
activation was predominantly associated with nuclear shrinkage, fragmentation, and apoptotic body formation characteristic of apoptosis. Results of this study indicate that rapid mechanical stretch injury to septo-hippocampal cell cultures replicates several important biochemical and morphological alterations commonly observed in vivo brain injury, although important differences were also noted.
...
PMID:Stretch injury causes calpain and caspase-3 activation and necrotic and apoptotic cell death in septo-hippocampal cell cultures. 1077 13
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