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)

Oxidant-induced death and dysfunction of pulmonary vascular cells play important roles in the evolution of acute lung injury. In pulmonary artery endothelial cells (PAECs), oxidant-mediated damage to mitochondrial DNA (mtDNA) seems to be critical in initiating cytotoxicity inasmuch as overexpression of the mitochondrially targeted human DNA repair enzyme, human Ogg1 (hOgg1), prevents both mtDNA damage and cell death (Dobson AW, Grishko V, LeDoux SP, Kelley MR, Wilson GL, and Gillespie MN. Am J Physiol Lung Cell Mol Physiol 283: L205-L210, 2002). The mechanism by which mtDNA damage leads to PAEC death is unknown, and the present study tested the specific hypothesis that enhanced mtDNA repair suppresses PAEC mitochondrial dysfunction and apoptosis evoked by xanthine oxidase (XO). PAECs transfected either with an adenoviral vector encoding hOgg1 linked to a mitochondrial targeting sequence or with empty vector were challenged with ascending doses of XO plus hypoxanthine. Quantitative Southern blot analyses revealed that, as expected, hOgg1 overexpression suppressed XO-induced mtDNA damage. Mitochondrial overexpression of hOgg1 also suppressed the XO-mediated loss of mitochondrial membrane potential. Importantly, hOgg1 overexpression attenuated XO-induced apoptosis as detected by suppression of caspase-3 activation, by reduced DNA fragmentation, and by a blunted appearance of condensed, fragmented nuclei. These observations suggest that mtDNA damage serves as a trigger for mitochondrial dysfunction and apoptosis in XO-treated PAECs.
 ...
PMID:Mitochondrial DNA damage triggers mitochondrial dysfunction and apoptosis in oxidant-challenged lung endothelial cells. 1556 90

Multiple myeloma (MM) accounts for 1 % of all cancer deaths. Although treated aggressively, almost all myelomas eventually recur and become resistant to treatment. Atiprimod (2-(3-Diethylaminopropyl)-8,8-dipropyl-2-azaspiro[4,5] decane dimaleate) has exerted anti-inflammatory activities and inhibited oeteoclast-induced bone resorption in animal models and been well tolerated in patients with rheumatoid arthritis in phase I clinical trials. Therefore, we investigated its activity in MM cells and its mechanism of action. We found that Atiprimod inhibited proliferation of the myeloma cell lines U266-B1, OCI-MY5, MM-1, and MM-1R in a time- and dose-dependent manner. Atiprimod blocked U266-B1 myeloma cells in the G(0)/G(1) phase, preventing cell cycle progression. Furthermore, Atiprimod inhibited signal transducer and activator of transcription (STAT) 3 activation, blocking the signalling pathway of interleukin-6, which contributes to myeloma cell proliferation and survival, and downregulated the antiapoptotic proteins Bcl-2, Bcl-X(L), and Mcl-1. Incubation of U266-B1 myeloma cells with Atiprimod induced apoptosis through the activation of caspase 3 and subsequent cleavage of the DNA repair enzyme poly(adenosine diphosphate-ribose) polymerase. Finally, Atiprimod suppressed myeloma colony-forming cell proliferation in fresh marrow cells from five patients with newly diagnosed MM in a dose-dependent fashion. These data suggest that Atiprimod has a role in future therapies for MM.
 ...
PMID:Atiprimod blocks STAT3 phosphorylation and induces apoptosis in multiple myeloma cells. 1597 Sep 28

Cytokine stimulation induces proliferation and growth of acute myeloid leukemia (AML) blasts and high levels of cytokines have been associated with poor prognosis in AML. The Jak-Stat pathway constitutes a major mediator of cytokine activity. We investigated whether WP-1034, a novel Jak-Stat inhibitor, is active against AML blasts. OCIM2 and fresh AML cells were incubated with 1 to 6 microM WP-1034 to determine its effect on proliferation. WP-1034 effectively inhibited proliferation of OCIM2 cells and fresh AML samples. We then analyzed the expressions of Stat 1, 3, and 5, as well as Phospho-Stat 1, 3, and 5 by Western immunoblotting after incubation of OCIM2 cells without and with 1 to 10 microM WP-1034 for 2 hours, and at 5 microM from 20 minutes up to 4 hours and found that WP-1034 blocked Stat 3 and 5 activation. Analysis of cell cycle status by PI staining and flow cytometry showed that WP-1034 caused cell cycle arrest of OCIM2 cells in sub-Go phase. We then evaluated the induction of apoptosis of OCIM2 cells following incubation with WP-1034 at 3 to 6 microM by annexin V-CY5 assay and analyzed caspase 3 and PARP cleavage using Western immunoblotting. We found that WP-1034 induced apoptosis of OCIM2 cells and that induction of apoptosis involved cleavage of caspase 3 and the DNA repair enzyme poly (adenosine diphosphate [ADP]-ribose) polymerase (PARP). Taken together, our data suggest that WP-1034 is a potent inhibitor of AML cell proliferation by inhibition of Stat 3 and 5 and induction of caspase-dependent apoptosis.
 ...
PMID:WP-1034, a novel JAK-STAT inhibitor, with proapoptotic and antileukemic activity in acute myeloid leukemia (AML). 1615 16

We have previously shown that hepatitis C virus (HCV) core protein modulates multiple cellular processes, including those that inhibit tumor necrosis factor alpha (TNF-alpha)-mediated apoptosis. In this study, we have investigated the signaling mechanism for inhibition of TNF-alpha-mediated apoptosis in human hepatoma (HepG2) cells expressing core protein alone or in context with other HCV proteins. Activation of caspase-3 and the cleavage of DNA repair enzyme poly(ADP-ribose) polymerase were inhibited upon TNF-alpha exposure in HCV core protein-expressing HepG2 cells. In vivo protein-protein interaction studies displayed an association between TNF receptor 1 (TNFR1) and TNFR1-associated death domain protein (TRADD), suggesting that the core protein does not perturb this interaction. A coimmunoprecipitation assay also suggested that HCV core protein does not interfere with the TRADD-Fas-associated death domain protein (FADD)-procaspase-8 interaction. Further studies indicated that HCV core protein expression inhibits caspase-8 activation by sustaining the expression of cellular FLICE (FADD-like interleukin-1beta-converting enzyme)-like inhibitory protein (c-FLIP). Similar observations were also noted upon expression of core protein in context to other HCV proteins expressed from HCV full-length plasmid DNA or a replicon. A decrease in endogenous c-FLIP by specific small interfering RNA induced TNF-alpha-mediated apoptotic cell death and caspase-8 activation. Taken together, our results suggested that the TNF-alpha-induced apoptotic pathway is inhibited by a sustained c-FLIP expression associated with the expression of HCV core protein, which may play a role in HCV-mediated pathogenesis.
 ...
PMID:Hepatitis C virus core protein inhibits tumor necrosis factor alpha-mediated apoptosis by a protective effect involving cellular FLICE inhibitory protein. 1661 96

(+)-Catechin possesses a broad range of pharmacological properties, including antioxidative effect. However, little is reported on the mechanism by which (+)-catechin protects microglia cells from DNA damage by oxidative stress. In this study, TUNEL assay and DNA electrophorysis indicated that (+)-catechin markedly blocked DNA fragmentation and apoptosis of microglia cells by tBHP exposure. A potent antioxidative effect of (+)-catechin was confirmed by comparison with a putative antioxidant agent, N-acetylcysteine at the lower doses. Furthermore, the increased intracellular ROS by tBHP exposure were scavenged by elevated activities of catalase (CAT) and superoxide dismutase (SOD) after (+)-catechin treatment. (+)-Catechin partially inhibited the activation of caspase-3, thereby both cleavage of poly (ADP-ribose) polymerase (PARP) and degradation of inhibitor of caspase-activated DNase (ICAD) were effectively abolished. In addition, the expression of PARP for repair of impaired DNA was significantly increased by (+)-catechin treatment. Taken together, these data suggest that protective effects of (+)-catechin against oxidative DNA damage of microglia cells is exerted by the increased expression of DNA repair enzyme PARP and antioxidant enzyme activities.
 ...
PMID:Elevated levels of DNA repair enzymes and antioxidative enzymes by (+)-catechin in murine microglia cells after oxidative stress. 1675 84

Homoharringtonine (HHT) is a plant alkaloid with antileukemic activity which is currently being used for treatment of acute and chronic leukemias. The present studies have evaluated the effect of HHT on proliferation and apoptosis in human myeloma cells. Myeloma cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptotic cells and cell cycle were evaluated by flow cytometry. Level of caspase-8, caspase-9, caspase-3, and DNA repair enzyme poly (ADP-ribose) polymerase (PARP), were investigated using Western blot analysis. We found that HHT significantly inhibited the proliferation of human multiple myeloma (MM) cell lines and tumor cells from patients with relapsed refractory MM in a dose-dependent manner. HHT also induced apoptosis in myeloma cells as evidenced by flow cytometric detection of annexin V binding assay. This apoptotic process was associated with the activation of caspase-8, caspase-9, caspase-3 and PARP. The results also demonstrate that HHT potentiates dexamethasone-induced killing of MM cells. These findings indicate that HHT may be effective in the treatment of MM.
 ...
PMID:Homoharringtonine induces apoptosis and growth arrest in human myeloma cells. 1761 69

The inflammatory process plays a pivotal role during the pathogenesis of osteoarthritis, dominated by catabolic processes initiated by pro-inflammatory cytokines such as IL-1beta. Resveratrol, a natural phytoalexin occurring in various fruits has previously been shown to exhibit anti-inflammatory properties in several cell types. We investigated, whether resveratrol may be a useful blocker of pro-inflammatory cytokine signalling pathways in arthritis. We first examined the effects of resveratrol on the proliferation and production of IL-1beta in primary human articular chondrocytes treated with IL-1betain vitro. Resveratrol reversed significantly IL-1beta-reduced cell proliferation and blocked IL-1beta-stimulated cell membrane bound- and mature IL-1beta synthesis in chondrocytes. Furthermore, resveratrol was able to inhibit the IL-1beta-induced degradation of mitochondria and apoptosis in chondrocytes in a time-dependent manner. Because caspase inhibitor Z-DEVD-FMK abolished the IL-1beta-induced apoptosis in chondrocytes, we examined the effect of resveratrol on the caspase pathway and found that resveratrol blocked the cysteine protease caspase-3 and subsequent cleavage of the DNA repair enzyme PARP. Additionally, resveratrol reversed the IL-1beta-induced up-regulation of reactive oxygen species (ROS) in chondrocytes. Finally, we show that resveratrol induced ubiquitin-independent degradation of tumor suppressor gene protein p53 and inhibited p53-induced apoptosis in chondrocytes in a dose-dependent manner. Our results indicate that resveratrol seems to be an effective in vitro anti-inflammatory agent and has a chondroprotective capacity through suppression of (1) IL-1beta- (2) ROS- and (3) tumor suppressor protein p53-production. Further studies should be undertaken to define a possible implication of resveratrol in osteoarthritis therapy and cartilage tissue engineering.
 ...
PMID:Regulation of inflammation signalling by resveratrol in human chondrocytes in vitro. 1795 54

We previously reported that cells harboring the hepatitis C virus (HCV) RNA replicon as well as those expressing HCV NS3/4A exhibited increased sensitivity to suboptimal doses of apoptotic stimuli to undergo mitochondrion-mediated apoptosis (Y. Nomura-Takigawa, et al., J. Gen. Virol. 87:1935-1945, 2006). Little is known, however, about whether or not HCV infection induces apoptosis of the virus-infected cells. In this study, by using the chimeric J6/JFH1 strain of HCV genotype 2a, we demonstrated that HCV infection induced cell death in Huh7.5 cells. The cell death was associated with activation of caspase 3, nuclear translocation of activated caspase 3, and cleavage of DNA repair enzyme poly(ADP-ribose) polymerase, which is known to be an important substrate for activated caspase 3. These results suggest that HCV-induced cell death is, in fact, apoptosis. Moreover, HCV infection activated Bax, a proapoptotic member of the Bcl-2 family, as revealed by its conformational change and its increased accumulation on mitochondrial membranes. Concomitantly, HCV infection induced disruption of mitochondrial transmembrane potential, followed by mitochondrial swelling and release of cytochrome c from mitochondria. HCV infection also caused oxidative stress via increased production of mitochondrial superoxide. On the other hand, HCV infection did not mediate increased expression of glucose-regulated protein 78 (GRP78) or GRP94, which are known as endoplasmic reticulum (ER) stress-induced proteins; this result suggests that ER stress is not primarily involved in HCV-induced apoptosis in our experimental system. Taken together, our present results suggest that HCV infection induces apoptosis of the host cell through a Bax-triggered, mitochondrion-mediated, caspase 3-dependent pathway(s).
 ...
PMID:Hepatitis C virus infection induces apoptosis through a Bax-triggered, mitochondrion-mediated, caspase 3-dependent pathway. 1876 89

Apoptosis is essential for the maintenance of inherited genomic integrity. During DNA damage-induced apoptosis, mechanisms of cell survival, such as DNA repair are inactivated to allow cell death to proceed. Here, we describe a role for the mammalian DNA repair enzyme Exonuclease 1 (Exo1) in DNA damage-induced apoptosis. Depletion of Exo1 in human fibroblasts, or mouse embryonic fibroblasts led to a delay in DNA damage-induced apoptosis. Furthermore, we show that Exo1 acts upstream of caspase-3, DNA fragmentation and cytochrome c release. In addition, induction of apoptosis with DNA-damaging agents led to cleavage of both isoforms of Exo1. The cleavage of Exo1 was mapped to Asp514, and shown to be mediated by caspase-3. Expression of a caspase-3 cleavage site mutant form of Exo1, Asp514Ala, prevented formation of the previously observed fragment without any affect on the onset of apoptosis. We conclude that Exo1 has a role in the timely induction of apoptosis and that it is subsequently cleaved and degraded during apoptosis, potentially inhibiting DNA damage repair.
 ...
PMID:Involvement of Exo1b in DNA damage-induced apoptosis. 1933 15

Thiazolidinediones (TZDs), such as troglitazone (TRO) and rosiglitazone (ROSI), improve insulin resistance by acting as ligands for the nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARgamma). TRO was withdrawn from the market because of reports of serious hepatotoxicity. A growing body of evidence suggests that TRO caused mitochondrial dysfunction and induction of apoptosis in human hepatocytes but its mechanisms of action remain unclear. We hypothesized that damage to mitochondrial DNA (mtDNA) is an initiating event involved in TRO-induced mitochondrial dysfunction and hepatotoxicity. Primary human hepatocytes were exposed to TRO and ROSI. The results obtained revealed that TRO, but not ROSI at equimolar concentrations, caused a substantial increase in mtDNA damage and decreased ATP production and cellular viability. The reactive oxygen species (ROS) scavenger, N-acetyl cystein (NAC), significantly diminished the TRO-induced cytotoxicity, suggesting involvement of ROS in TRO-induced hepatocyte cytotoxicity. The PPARgamma antagonist (GW9662) did not block the TRO-induced decrease in cell viability, indicating that the TRO-induced hepatotoxicity is PPARgamma-independent. Furthermore, TRO induced hepatocyte apoptosis, caspase-3 cleavage and cytochrome c release. Targeting of a DNA repair protein to mitochondria by protein transduction using a fusion protein containing the DNA repair enzyme Endonuclease III (EndoIII) from Escherichia coli, a mitochondrial translocation sequence (MTS) and the protein transduction domain (PTD) from HIV-1 TAT protein protected hepatocytes against TRO-induced toxicity. Overall, our results indicate that significant mtDNA damage caused by TRO is a prime initiator of the hepatoxicity caused by this drug.
 ...
PMID:Troglitazone, but not rosiglitazone, damages mitochondrial DNA and induces mitochondrial dysfunction and cell death in human hepatocytes. 1963 56


<< Previous 1 2 3 4 5 Next >>