Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P42574 (caspase-3)
45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A transient burst of poly(ADP-ribosyl)ation of nuclear proteins occurs early, prior to commitment to death, in human osteosarcoma cells undergoing apoptosis, followed by caspase-3-mediated cleavage of poly(ADP-ribose) polymerase (PARP). The generality of this early burst of poly(ADP-ribosyl)ation has now been investigated with human HL-60 cells, mouse 3T3-L1, and immortalized fibroblasts derived from wild-type mice. The effects of eliminating this early transient modification of nuclear proteins by depletion of PARP protein either by antisense RNA expression or by gene disruption on various morphological and biochemical markers of apoptosis were then examined. Marked caspase-3-like PARP cleavage activity, proteolytic processing of CPP32 to its active form, internucleosomal DNA fragmentation, and nuclear morphological changes associated with apoptosis were induced in control 3T3-L1 cells treated for 24 h with anti-Fas and cycloheximide but not in PARP-depleted 3T3-L1 antisense cells exposed to these inducers. Similar results were obtained with control and PARP-depleted human Jurkat T cells. Whereas immortalized PARP +/+ fibroblasts showed the early burst of poly(ADP-ribosyl)ation and a rapid apoptotic response when exposed to anti-Fas and cycloheximide, PARP -/- fibroblasts exhibited neither the early poly (ADP-ribosyl)ation nor any of the biochemical or morphological changes characteristic of apoptosis when similarly treated. Stable transfection of PARP -/- fibroblasts with wild-type PARP rendered the cells sensitive to Fas-mediated apoptosis. These results suggest that PARP and poly(ADP-ribosyl)ation may trigger key steps in the apoptotic program. Subsequent degradation of PARP by caspase-3-like proteases may prevent depletion of NAD and ATP or release certain nuclear proteins from poly(ADP-ribosyl)ation-induced inhibition, both of which might be required for late stages of apoptosis.
...
PMID:Transient poly(ADP-ribosyl)ation of nuclear proteins and role of poly(ADP-ribose) polymerase in the early stages of apoptosis. 959 11

Treatment with cytosine beta-D-arabinoside (AraC; 300 microM) induced a time-dependent accumulation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein in nuclei purified from cultured cerebellar granule cells, with a concomitant degradation of lamin B1, a nuclear membrane protein and a substrate of CPP32/caspase-3. Moreover, Asp-Glu-Val-Asp-fluoromethyl ketone (DEVD-fmk), a CPP32-selective antagonist, dose-dependently suppressed AraC-induced apoptosis of these neurons. Nuclear accumulation of GAPDH protein was associated with a progressive decrease in the activity of uracil-DNA glycosylase (UDG), one of the nuclear functions of GAPDH. The nuclear dehydrogenase activity of GAPDH was initially increased after treatment and then decreased parallel to UDG activity. Six GAPDH isoforms were detected in the nuclei of AraC-treated cells. The more alkaline isoforms, 1-3, constituted the bulk of the nuclear GAPDH, and the remaining isoforms, 4-6, were the minor species. Levels of all six isoforms were increased after treatment with AraC for 16 h; a 4-h treatment increased levels of only isoforms 4 and 5. Thus, it appears that various GAPDH isoforms are differentially regulated and may have distinct apoptotic roles. Pretreatment with GAPDH antisense oligonucleotide blocked the nuclear translocation of GAPDH isoforms, and the latter process occurred concurrently with a decrease in cytosolic GAPDH isoforms. Sodium nitroprusside-induced NAD labeling of nuclear GAPDH showed a 60% loss of GAPDH labeling after AraC treatment, suggesting that the active site of GAPDH may be covalently modified, denatured, or improperly folded. The unfolded protein response elicited by denatured GAPDH may contribute to AraC-induced neuronal death.
...
PMID:Nuclear translocation of glyceraldehyde-3-phosphate dehydrogenase isoforms during neuronal apoptosis. 1003 63

The purpose of this study was to determine if exacerbation of apoptosis precedes liver injury during chronic exposure of rats to alcohol. After 7 weeks of feeding an alcohol- or dextrin-containing liquid diet, the animals were treated with gram-negative bacterial lipopolysaccharide (1 mg x kg(-1) body weight, intravenously) or sterile saline and sacrificed 3 hr after the treatment. Alanine:2-oxoglutarate aminotransferase (ALT) and lactate:NAD oxidoreductase [lactate dehydrogenase (LDH)] were measured in plasma. The caudate lobe of the liver was resected for histology, while the rest of the organ was perfused with collagenase to isolate hepatocytes, Kupffer cells (KCs), and sinusoidal endothelial cells (SECs) by centrifugal elutriation. Hepatocyte mitochondria were isolated by differential centrifugation of the cell homogenate. Reduced and oxidized glutathione (GSH and GSSG) in isolated hepatocytes and hepatocyte mitochondria, and malondialdehyde in hepatocytes were assayed. Caspase-3 activity and Fas ligand mRNA expression were determined in hepatocytes, KCs, and SECs. Plasma ALT and LDH activity, liver histology, GSH, GSSG and their ratio, and malondialdehyde content were not affected by alcohol treatment Caspase-3 activity was significantly increased in alcohol-treated rats in all three cell types, with the lowest response observed in hepatocytes and the highest in KCs. Fas ligand mRNA expression, which had the highest level in SECs, followed by KCs and hepatocytes, was not affected by alcohol administration. Lipopolysaccharide had the following effects: an increase in ALT in both pair- and alcohol-fed rats, and LDH only in alcohol-fed rats, a decrease in GSH + GSSG levels in both mitochondria and hepatocytes, an elevation of malondialdehyde content in hepatocytes, a raise in caspase-3 activity in all groups and cell types, and an augmentation of Fas ligand expression in hepatocytes and KCs, but not in SECs. These data suggest that, during chronic alcohol consumption, an exacerbated apoptosis precedes alcohol-induced liver injury.
...
PMID:Modulation of caspase-3 activity and Fas ligand mRNA expression in rat liver cells in vivo by alcohol and lipopolysaccharide. 1006 67

An early transient burst of poly(ADP-ribosyl)ation of nuclear proteins was recently shown to be required for apoptosis to proceed in various cell lines (Simbulan-Rosenthal, C., Rosenthal, D., Iyer, S., Boulares, H., and Smulson, M. (1998) J. Biol. Chem. 273, 13703-13712) followed by cleavage of poly(ADP-ribose) polymerase (PARP), catalyzed by caspase-3. This inactivation of PARP has been proposed to prevent depletion of NAD (a PARP substrate) and ATP, which are thought to be required for later events in apoptosis. The role of PARP cleavage in apoptosis has now been investigated in human osteosarcoma cells and PARP -/- fibroblasts stably transfected with a vector encoding a caspase-3-resistant PARP mutant. Expression of this mutant PARP increased the rate of staurosporine and tumor necrosis factor-alpha-induced apoptosis, at least in part by reducing the time interval required for the onset of caspase-3 activation and internucleosomal DNA fragmentation, as well as the generation of 50-kilobase pair DNA breaks, thought to be associated with early chromatin unfolding. Overexpression of wild-type PARP in osteosarcoma cells also accelerated the apoptotic process, although not to the same extent as that apparent in cells expressing the mutant PARP. These effects of the mutant and wild-type enzymes might be due to the early and transient poly(ADP-ribose) synthesis in response to DNA breaks, and the accompanying depletion of NAD apparent in the transfected cells. The accelerated NAD depletion did not seem to interfere with the later stages of apoptosis. These results indicate that PARP activation and subsequent cleavage have active and complex roles in apoptosis.
...
PMID:Role of poly(ADP-ribose) polymerase (PARP) cleavage in apoptosis. Caspase 3-resistant PARP mutant increases rates of apoptosis in transfected cells. 1043 58

Endothelial cells (EC) are subject to oxidative-induced cell death. Activation of poly(ADP-ribose) polymerase (PARP) occurs early in oxidant-induced EC injury and putatively mediates cell death by depleting its substrate, NAD(+). In this study, the role of PARP in H(2)O(2)-induced EC death was investigated. EC were exposed to oxidant stress and viability continuously monitored using fluorescent dye exclusion. Inhibition of PARP with 1, 5-dihydroxyisoquinoline (DIQ) delayed the time course of oxidant-induced EC death. Concurrent addition of the protein synthesis inhibitor, cycloheximide, or the endonuclease inhibitor, aurintricarboxylic acid, to PARP-inhibited cells further delayed the onset and attenuated the extent of H(2)O(2)-induced cell lysis, consistent with an active mode of cell death. Caspase-3-like activity, a hallmark of apoptosis, was negligible in oxidant-treated EC alone, however, inhibition of PARP by 3-aminobenzamide or DIQ dramatically increased caspase-3-like activity. Morphological assessment confirmed that the primary mode of death in oxidant-stressed EC was oncosis. However, following PARP inhibition, the cells switched to apoptosis. Since inflammation is associated with oncosis and not apoptosis, the results presented here could explain the beneficial effects seen with PARP inhibition in various in vivo models of oxidant injury and provide a mechanism to manipulate this injury into a state of cell death that could ultimately be controlled.
...
PMID:Poly(ADP-ribose) polymerase inhibition in oxidant-stressed endothelial cells prevents oncosis and permits caspase activation and apoptosis. 1047 25

Jurkat T cells showed a major, early decrease in blue autofluorescence in response to Fas/Apo-1/CD95 cross-linking or stimulation with cell-permeant ceramide. This indicates the oxidation/depletion of NADH or NADPH before the onset of apoptosis. Kinetic studies, cytofluorimetric multiparameter analyses and cell sorting experiments indicated a close temporal relationship between NAD(P)H oxidation/depletion and the dissipation of the mitochondrial transmembrane potential (DeltaPsi(m)). In contrast, NAD(P)H depletion was detected well before several other changes associated with late apoptosis, including enhanced superoxide generation, phosphatidylserine exposure on the cell surface, loss of cytosolic K(+), decreased cytoplasmic pH, nuclear DNA fragmentation, cell shrinkage, loss of viability and the appearance of the mitochondrial antigen APO2.7. Full activation of caspase 9 and caspase 3 appeared to be correlated with the appearance of superoxide anions in the mitochondria, and followed the drop in NADPH. Overexpression of the apoptosis-inhibitory proto-oncogene Bcl-2, which encodes an inhibitor of the mitochondrial permeability transition (PT) pore, delayed both the DeltaPsi(m) disruption and the depletion of NAD(P)H. Similar effects were observed with the pharmacological PT pore inhibitors, bongkrekic acid and cyclosporin A. Thus there appears to be a close functional relationship between mitochondrial and cellular redox changes during early apoptosis; events that are inhibited by Bcl-2.
...
PMID:Oxidation of pyridine nucleotides during Fas- and ceramide-induced apoptosis in Jurkat cells: correlation with changes in mitochondria, glutathione depletion, intracellular acidification and caspase 3 activation. 1113 1

During apoptosis, endonucleases cleave DNA into 50-300-kb fragments and subsequently into internucleosomal fragments. DNA fragmentation factor (DFF) is implicated in apoptotic DNA cleavage; this factor comprises DFF45 and DFF40 subunits, the former of which acts as a chaperone and inhibitor of the catalytic subunit and whose cleavage by caspase-3 results in DFF activation. Disruption of the DFF45 gene blocks internucleosomal DNA fragmentation and confers resistance to apoptosis in primary thymocytes. The role of DFF-mediated DNA fragmentation in apoptosis was investigated in primary fibroblasts from DFF45(-/-) and control (DFF45(+/+)) mice. DFF45 deficiency rendered fibroblasts resistant to apoptosis induced by tumor necrosis factor (TNF). TNF induced rapid cleavage of DNA into approximately 50-kb fragments in DFF45(+/+) fibroblasts but not in DFF45(-/-) cells, indicating that DFF mediates this initial step in DNA processing. The TNF-induced activation of poly(ADP-ribose) polymerase (PARP), which requires PARP binding to DNA strand breaks, and the consequent depletion of the PARP substrate NAD were markedly delayed in DFF45(-/-) cells, suggesting a role for DFF in PARP activation. The activation of caspase-3 and mitochondrial events important in apoptotic signaling, including the loss of mitochondrial membrane potential and the release of cytochrome c, induced by TNF were similarly delayed in DFF45(-/-) fibroblasts. DFF45(-/-) and DFF45(+/+) cells were equally sensitive to the DNA-damaging agent and PARP activator N-methyl-N'-nitro-N-nitrosoguanidine. Inhibition of PARP by 3-aminobenzamide partially protected DFF45(+/+) cells against TNF-induced death and inhibited the associated release of cytochrome c and activation of caspase-3. These results suggest that the generation of 50-kb DNA fragments by DFF, together with the activation of PARP, mitochondrial dysfunction, and caspase-3 activation, contributes to an amplification loop in the death process.
...
PMID:Roles of DNA fragmentation factor and poly(ADP-ribose) polymerase in an amplification phase of tumor necrosis factor-induced apoptosis. 1146

Several endonucleases are implicated in the internucleosomal DNA fragmentation associated with apoptosis. The human Ca2+- and Mg2+-dependent endonuclease DNAS1L3 is inhibited by poly(ADP-ribosyl)ation in vitro, and its activation during apoptosis shows a time course similar to that of the cleavage of poly(ADP-ribose) polymerase-1 (PARP-1). The role of the cleavage and consequent inactivation of PARP-1 by caspase-3 in the activation of DNAS1L3 has now been investigated further both in vitro and in vivo. In an in vitro system based on purified recombinant proteins and NAD, caspase-3 prevented the inhibition of DNAS1L3 endonuclease activity by wild-type PARP-1 but not that induced by a caspase-3-resistant PARP-1 mutant. The induction by etoposide of apoptosis in human osteosarcoma cells (which were shown not to express endogenous DNAS1L3) was accompanied by internucleosomal DNA fragmentation only after transfection of the cells with a plasmid encoding DNAS1L3. This DNA fragmentation in etoposide-treated cells was blocked by 1,2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid, an inhibitor of intracellular Ca2+ release. Expression of the endonuclease subunit of DNA fragmentation factor (DFF40) and cleavage of its inhibitor, DFF45, were not sufficient to cause internucleosomal DNA fragmentation in osteosarcoma cells during etoposide-induced apoptosis. Coexpression of caspase-3-resistant PARP-1 mutant with DNAS1L3 in osteosarcoma cells blocked etoposide-induced internucleosomal DNA fragmentation and resulted in persistent poly(ADP-ribosyl)ation of DNAS1L3; it did not, however, prevent the activation of caspase-3 and the consequent cleavage of endogenous PARP-1. These results indicate that PARP-1 cleavage during apoptosis is not simply required to prevent excessive depletion of NAD and ATP but is also necessary to release DNAS1L3 from poly(ADP-ribosyl)ation-mediated inhibition.
...
PMID:Regulation of DNAS1L3 endonuclease activity by poly(ADP-ribosyl)ation during etoposide-induced apoptosis. Role of poly(ADP-ribose) polymerase-1 cleavage in endonuclease activation. 1169 7

Poly(ADP-ribosyl)ation is an important mechanism for the maintenance of genomic integrity in response to DNA damage. The enzyme responsible for poly(ADP-ribose) synthesis, poly(ADP-ribose) polymerase 1 (PARP-1), has been implicated in two distinct modes of cell death induced by DNA damage, namely apoptosis and necrosis. During the execution phase of apoptosis, PARP-1 is specifically proteolyzed by caspases to produce an N-terminal DNA-binding domain (DBD) and a C-terminal catalytic fragment. The functional consequence of this proteolytic event is not known. However, it has recently been shown that overactivation of full-length PARP-1 can result in energy depletion and necrosis in dying cells. Here, we investigate the molecular basis for the differential involvement of PARP-1 in these two types of cellular demise. We show that the C-terminal apoptotic fragment of PARP-1 loses its DNA-dependent catalytic activity upon cleavage with caspase 3. However, the N-terminal apoptotic fragment, retains a strong DNA-binding activity and totally inhibits the catalytic activity of uncleaved PARP-1. This dominant-negative behavior was confirmed and extended in cellular extracts where DNA repair was completely inhibited by nanomolar concentrations of the N-terminal fragment. Furthermore, overexpression of the apoptotic DBD in mouse fibroblast inhibits endogenous PARP-1 activity very efficiently in vivo, thereby confirming our biochemical observations. Taken together, these experiments indicate that the apoptotic DBD of PARP-1 acts cooperatively with the proteolytic inactivation of the enzyme to trans-inhibit NAD hydrolysis and to maintain the energy levels of the cell. These results are consistent with a model in which cleavage of PARP-1 promotes apoptosis by preventing DNA repair-induced survival and by blocking energy depletion-induced necrosis.
...
PMID:Gain-of-function of poly(ADP-ribose) polymerase-1 upon cleavage by apoptotic proteases: implications for apoptosis. 1170 29

We recently described that there is a feedback amplification of cytochrome c release from mitochondria by caspases. Here we investigated how caspases impact on mitochondria to induce cytochrome c release and found that recombinant caspase-3 induced opening of permeability transition pore and reduction of membrane potential in vitro. These events were inhibited by Bcl-xL, cyclosporin A and z-VAD.fmk. Moreover, caspase-3 stimulated the rate of mitochondrial state 4 respiration, superoxide production and NAD(P)H oxidation in a Bcl-xL- and cyclosporin A-inhibitable manner. These results suggest that caspase-3 induces cytochrome c release by inducing permeability transition pore opening which is associated with changes in mitochondrial respiration and redox potential.
...
PMID:A study on permeability transition pore opening and cytochrome c release from mitochondria, induced by caspase-3 in vitro. 1175 32


1 2 3 4 5 6 7 8 9 10 Next >>