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

Endoplasmic reticulum (ER) stress has increasingly come into focus as a factor contributing to neuronal injury. Although caspase-dependent mechanisms have been implicated in ER stress, the signaling pathways involved remain unclear. In this study, we examined the role of the extracellular signal-regulated kinase (ERK), a mitogen-activated protein (MAP) kinase pathway that is highly conserved in many systems for balancing cell survival and death. Prolonged treatment of the human neuroblastoma cell line SH-SY5Y with thapsigargin, an inducer of ER stress, increased cell death over 24-48 h, as measured by LDH release. Caspases were involved; increased levels of active caspase-3 and cleaved caspase substrate PARP were detected, and treatment with Z-VAD-FMK reduced thapsigargin-induced cytotoxicity. In contrast, inhibition of calpain was not protective, although calpain was activated following thapsigargin treatment. An early and transient phosphorylation of ERK1/2 occurred after thapsigargin-induced ER stress, and targeting this pathway with the MEK inhibitors U0126 or PD98059 significantly reduced cell death. Similar cytoprotection was obtained against brefeldin A, another ER stress agent. However, protection against ER stress via ERK inhibition was not accompanied by amelioration of caspase-3 activation, PARP cleavage, or DNA laddering. These data indicate that ERK may contribute to non-caspase-dependent pathways of injury after ER stress.
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PMID:Involvement of ERK MAP kinase in endoplasmic reticulum stress in SH-SY5Y human neuroblastoma cells. 1503 Apr 7

The balance between polymorphonuclear leukocytes (PMNL) apoptosis and necrosis in inflamed tissues is an important determinant of the degree of tissue injury. To prevent senescent PMNL from releasing their toxic contents into surrounding tissues, these cells become apoptotic and are then internalized by tissue macrophages. PMNL apoptosis and subsequent ingestion by macrophages are the major mechanisms for clearing PMNL that have been recruited to the inflamed sites and thus for promoting resolution of the inflammation. PMNL have a short half-life that is extended at the inflamed site by pro-inflammatory cytokines including Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF), Interleukin-8 (IL-8), Gro-alpha, and they contact with the bacterial cell walls containing lipopolysaccharides (LPS). Conversely, anti-inflammatory cytokines, such as IL-10, accelerate the apoptosis of LPS-activated PMNL. Spontaneous PMNL apoptosis does not require Fas ligation but involves proteolytic cascades -caspases (particularly caspases 3 and 8), calpains and the proteasome-that activate kinases, e.g. caspase 3-mediated activation of protein kinase C-delta, dissociate actin-binding proteins from filamentous actin, and participate in cell surface as well as nuclear morphological transformations. Members of the Bcl-2 protein family, Mcl-1 and A1, are involved in the regulation of PMNL apoptosis. Cell surface receptors and protein kinases, particularly mitogen-activated protein kinases (MAPK), also play critical roles in transducing the signals that result in PMNL apoptosis or extended survival. A growing understanding of the mechanisms regulating leukocyte apoptosis and of the molecules mediating safe phagocytic clearance of dying cells may yield new insights into the pathogenesis of inflammatory diseases. In this regard, therapeutic strategies to resolve chronic inflammation could usefully target PMNL. This review summarises current knowledge on the molecular mechanisms and components of PMNL apoptosis.
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PMID:Molecular regulation of neutrophil apoptosis and potential targets for therapeutic strategy against the inflammatory process. 1503 37

Actinobacillus actinomycetemcomitans is a major periodontopathic bacterium with multiple virulence factors, including lipopolysaccharide (LPS). Previous reports have demonstrated that LPS induced apoptosis in a murine macrophage-like cell line, J744.1, as well as in peritoneal macrophages from C3H/HeN mice in the presence of cycloheximide (CHX). However, the detailed molecular mechanisms involved in the apoptosis of macrophages induced by LPS and CHX are not well known. To clarify the possible role of LPS in the induction of macrophage apoptosis, we investigated cell death induced by LPS from A. actinomycetemcomitans and CHX in human macrophage-like U937 cells, which were differentiated by 12-O-tetradecanoylphorbol 13-acetate (TPA), and also assessed the molecular mechanisms involved in the process. We found that TPA-differentiated U937 cells usually showed resistance to LPS-induced apoptosis. However, in the presence of CHX, LPS induced release of cytochrome c without modifying steady-state levels of Bcl-2, Bcl-xL, Bax, and Bak. Treatment with LPS in the presence of CHX also led to activation of caspase-3 and apoptosis via, in part, the CD14/toll-like receptor 4 (TLR4). The induction of cytochrome c release may have been due to dephosphorylation of Akt and Bad, which were cooperatively induced by CHX and LPS. However, endogenous tumor necrosis factor alpha- and Fas-induced signals, extracellular signal-regulated kinase kinase/mitogen-activated protein kinases and I-kappa B alpha/nuclear factor-kappa B (NF-kappa B) were not required for caspase-3-dependent apoptosis. These results emphasize the possible important role of the mitochondrial apoptotic pathway leading to caspase-3 activation in LPS-induced apoptosis of human macrophages in the presence of CHX.
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PMID:Mechanisms involved in apoptosis of human macrophages induced by lipopolysaccharide from Actinobacillus actinomycetemcomitans in the presence of cycloheximide. 1503 4

G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptors (GPCRs) activate numerous cellular signals through the combined actions of G proteins, GPCR kinases, and arrestins. Although arrestins have traditionally been thought of as mediating GPCR desensitization, they have now been shown to play important roles in the internalization, trafficking, and signaling of many GPCRs. We demonstrate that in cells devoid of arrestins, the stimulation of numerous GPCRs including the N-formyl peptide receptor (FPR) initiates rapid cell rounding, annexin V positivity, and caspase activation followed by cell death. The apoptotic response is initiated by G protein signaling and involves activation of phosphoinositide 3-kinase, mitogen-activated protein kinases, and c-Src resulting in cytochrome c release from mitochondria and ultimately caspase 9 and caspase 3 activation. Reconstitution with either arrestin-2 or arrestin-3 is completely sufficient to prevent FPR-mediated apoptosis. Surprisingly, a non-desensitizing and non-internalizing mutant of the FPR is unable to initiate apoptosis, indicating that receptor phosphorylation and internalization, but not solely chronic activation due to a lack of desensitization, are critical determinants for the induction of apoptosis by the FPR. We further demonstrate that this response is not unique to the FPR with numerous additional GPCRs, including the V2 vasopressin, angiotensin II (type 1A), and CXCR2 receptors, capable of initiating apoptosis upon stimulation, whereas GPCRs such as the beta(2)-adrenergic receptor and CXCR4 are not capable of initiating apoptotic signaling. These data demonstrate for the first time that arrestins play a critical and completely unexpected role in the suppression GPCR-mediated apoptosis, which we show is a common consequence of GPCR-mediated cellular activation in the absence of arrestins.
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PMID:Arrestins block G protein-coupled receptor-mediated apoptosis. 1505 14

Astrocytes, the most abundant glial cell types in the brain, provide metabolic and trophic support to neurons and modulate synaptic activity. Accordingly, impairment in these astrocyte functions can critically influence neuronal survival. Recent studies show that astrocyte apoptosis may contribute to pathogenesis of many acute and chronic neurodegenerative disorders, such as cerebral ischemia, Alzheimer's disease and Parkinson's disease. We found that incubation of cultured rat astrocytes in a Ca(2+)-containing medium after exposure to a Ca(2+)-free medium causes an increase in intracellular Ca(2+) concentration followed by apoptosis, and that NF-kappa B, reactive oxygen species, and enzymes such as calpain, xanthine oxidase, calcineurin and caspase-3 are involved in reperfusion-induced apoptosis. Furthermore, we demonstrated that heat shock protein, mitogen-activated protein/extracellular signal-regulated kinase, phosphatidylinositol-3 kinase and cyclic GMP phosphodiesterase are target molecules for anti-apoptotic drugs. This review summarizes (1) astrocytic functions in neuroprotection, (2) current evidence of astrocyte apoptosis in both in vitro and in vivo studies including its molecular pathways such as Ca(2+) overload, oxidative stress, NF-kappa B activation, mitochondrial dysfunction, endoplasmic reticulum stress, and protease activation, and (3) several drugs preventing astrocyte apoptosis. As a whole, this article provides new insights into the potential role of astrocytes as targets for neuroprotection. In addition, the advance in the knowledge of molecular mechanisms of astrocyte apoptosis may lead to the development of novel therapeutic strategies for neurodegenerative disorders.
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PMID:Astrocyte apoptosis: implications for neuroprotection. 1506 28

Cantharidin is an active compound from blister beetles traditionally used for the treatment of cancer. It is known to exert its antitumor activity by inducing apoptosis in cancer cells. However, its signaling pathway still remains unclear. Therefore, we investigated the roles of the mitogen-activated protein kinases (MAPKs) and the tumor suppressor gene, p53, during cantharidin-induced apoptosis in U937 human leukemic cells. Cantharidin effectively activated ERK-1/2, p38 and JNK in U937 cells in a time- and dose-dependent manner. Cantharidin also exhibited a strong cytotoxicity and induced apoptosis in U937 cells. For the evaluation of the role of MAPKs, PD98059, SB202190 and SP600125 were used as MAPK inhibitors for ERK-1/2, p38 and JNK. PD98059 did not affect cantharidin-induced cytotoxicity and apoptosis, whereas SB202190 and SP600125 significantly interfered with cytotoxic and apoptotic activities induced by cantharidin. Cantharidin alone induced the apoptosis by phosphorylation of p53, up-regulation of downstream target genes, MDM2 and p21 and also cleaved caspase-3, whereas SB202190 and SP600125 caused the down-regulation of p53, MDM-2, p21 and cleaved caspase-3 after a co-treatment with cantharidin. Similarly, SB202190 and SP600125 significantly disturbed the caspase-3 activity after a co-treatment with cantharidin by colorimetric assay. Taken together, these results suggest that cantharidin can induce apoptosis by activation of p38 and JNK MAP kinase pathways associated with p53 and caspase-3.
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PMID:Roles of p38 and JNK mitogen-activated protein kinase pathways during cantharidin-induced apoptosis in U937 cells. 1513 Jul 58

Engagement of antigen receptors on immature B cells induces apoptosis, while at the mature stage, it stimulates cell activation and proliferation. The difference in B cell receptor (BCR)-mediated signaling pathways regulating death or survival of B cells is not fully understood. We aimed to characterize the pathway leading to BCR-driven apoptosis. Transitional immature B cells were obtained from the spleen of sublethally irradiated and auto-reconstituted mice. We have detected a short-lived BCR-driven activation of mitogen-activated protein kinases (ERK1/2 and p38 MAPK) and Akt/PKB in transitional immature B cells that correlated with the lack of c-Fos expression, reduced phosphorylation of Akt substrates and a susceptibility for apoptosis. Simultaneous signaling through BCR and CD40 protected immature B cells from apoptosis, however, without inducing Bcl-2 expression. The BCR-induced apoptosis of immature B cells is a result of the collapse of mitochondrial membrane potential and the subsequent activation of caspase-3.
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PMID:Antigen receptor-mediated signaling pathways in transitional immature B cells. 1515 67

The molecular mechanisms underlying H(2)O(2)-induced toxicity were characterized in rat oligodendrocyte cultures. While progenitor cells were more sensitive than mature oligodendrocytes to H(2)O(2), the antioxidant, N-acetyl-L-cysteine, blocked toxicity at both stages of development. Differentiated oligodendrocytes contained more glutathione than did progenitors and were less susceptible to decreases in glutathione concentration induced by H(2)O(2) stress. As free radicals have been considered to serve as second messengers, we examined the effect of H(2)O(2) on activation of the mitogen-activated protein kinases (MAPK), extracellular signal-regulated kinases (ERK) 1/2 and p38. H(2)O(2) caused a time- and concentration-dependent increase in MAPK phosphorylation, an effect that was totally blocked by N-acetyl-L-cysteine. Further exploration of potential mechanisms involved in oligodendrocyte cell death showed that H(2)O(2) treatment caused DNA condensation and fragmentation at both stages of development, whereas caspase 3 activation and poly (ADP-ribose) polymerase cleavage were significantly increased only in oligodendrocyte progenitors. The pan-caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp fluoromethyl ketone, blocked DNA fragmentation in progenitors and produced a small but significant level of protection from H(2)O(2) toxicity in progenitors and mature oligodendrocytes. In contrast, inhibitors of both p38 and MEK reduced H(2)O(2)-induced death most significantly in oligodendrocytes. The poly (ADP-ribose) polymerase inhibitor, PJ34, reduced H(2)O(2)-induced toxicity on its own but was most effective when combined with benzyloxycarbonyl-Val-Ala-Asp fluoromethyl ketone or PD169316. The finding that molecular mechanisms conferring resistance to reactive oxygen species toxicity are regulated during oligodendrocyte differentiation may be of importance in designing therapies for certain neurological diseases affecting white matter.
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PMID:Developmental differences in HO-induced oligodendrocyte cell death: role of glutathione, mitogen-activated protein kinases and caspase 3. 1522 96

Cadmium is a well-known carcinogenic and immunotoxic metal commonly found in cigarette smoke and industrial effluent. An altered intracellular calcium ([Ca(2+)](i)) level has been implicated in the pathophysiology of immune dysfunction. The present study was designed to determine the possible involvement of calcium (Ca(2+)) and mitogen-activated protein kinases (MAPKs) signaling pathways on cadmium-induced cell death in J774A.1 murine macrophage cells. Cadmium caused a low-amplitude [Ca(2+)](i) elevation at 20 microM and rapid and high-amplitude [Ca(2+)](i) elevation at 500 microM. Exposure to cadmium dose-dependently induced phosphorylation of c-Jun NH(2)-terminal kinase (JNK) and deactivated p38 MAPK. Use of the selective JNK inhibitor SP600125 suggested that activation of JNK is pro-apoptotic and pro-necrotic. Buffering of the calcium response with 1,2-bis-(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid tetrakis (acetoxy-methyl) ester (BAPTA-AM) and ethylene glycol-bis-(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) completely blocked cadmium-induced apoptotic response. The pretreatment of cells with BAPTA-AM and EGTA suppressed the cadmium-induced cell injury, including growth arrest, mitochondrial activity impairment, and necrosis, and it also recovered the cadmium-altered JNK and p38 MAPK activity. Chelating [Ca(2+)](i) also reversed cadmium-induced hydrogen peroxide generation, suggesting that production of reactive oxygen species (ROS) is related to [Ca(2+)](i). The present study showed that cadmium induces a [Ca(2+)](i)-ROS-JNK-caspase-3 signaling pathway leading to apoptosis. Furthermore, cadmium-induced [Ca(2+)](i) regulates phosphorylation/dephosphorylation of JNK and p38, and it modulates signal transduction pathways to proliferation, mitochondrial activity, and necrosis.
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PMID:Calcium-mediated activation of c-Jun NH2-terminal kinase (JNK) and apoptosis in response to cadmium in murine macrophages. 1525 39

Expression of the cytokine receptor CD30 is a characteristic feature of anaplastic large cell lymphoma (ALCL). Reports regarding CD30-mediated signaling in ALCL cells are highly controversial, especially with respect to the regulation of cell survival. In this study, we stimulated 6 ALCL-derived cell lines with immobilized anti-CD30 antibody. CD30-induced cell death was investigated by Western blot and FACS analysis. CD30-dependent cell proliferation and activation was analyzed by applying the trypan blue exclusion method and a luciferase-based ATP assay. The expression of cell cycle relevant proteins and the activation of mitogen-activated protein (MAP) kinases were also examined. We demonstrated that activation of CD30 did not lead to the cleavage of pro-caspase-3. FACS analysis confirmed that in all examined cells cell death was not mediated by CD30. Cell growth was strongly inhibited in 2 of the 6 cell lines and restrained cell growth was accompanied by expression of the cell cycle inhibitor p21(WAF1/CIP1). Furthermore, stimulation of CD30 led to the activation of the p38 MAP kinase but not of the extracellular signal-regulated kinase (ERK) or the jun N-terminal kinase (JNK). Interestingly, activation of CD30 induced a strong synergistic reduction of cell activity, if the p38 MAP kinase activity was blocked by SB203580. The aim of the study was to elucidate CD30-induced signaling in different ALCL-cells. Our results suggest that CD30-mediated apoptosis is not a common feature in this cell type and that p38 MAP kinase is involved in CD30-mediated singal transduction.
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PMID:Signal transduction in anaplastic large cell lymphoma cells (ALCL) mediated by the tumor necrosis factor receptor CD30. 1529 61


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