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)

We previously demonstrated that ginsenoside Rg(3) (Rg(3)), one of the active ingredients in Panax ginseng, attenuates NMDA receptor-mediated currents and NMDA-induced neurotoxicity (Kim, S., Kim, T., Ahn, K., Park, W.K., Nah, S.Y., Rhim, H., 2004. Ginsenoside Rg(3) antagonizes NMDA receptors through a glycine modulatory site in rat cultured hippocampal neurons. Biochem. Biophys. Res. Commun. 323, 416-424). Accumulating evidence suggests that homocysteine (HC), a metabolite of methionine, exerts its excitotoxicity through NMDA receptor activation. In the present study, we examined the neuroprotective effects of Rg(3) on HC-induced hippocampal excitotoxicity in vitro and in vivo. Our in vitro studies using rat cultured hippocampal neurons revealed that Rg(3) treatment significantly and dose-dependently inhibited HC-induced hippocampal cell death, with an EC(50) value of 28.7+/-7.5 muM. Rg(3) treatment not only significantly reduced HC-induced DNA damage, but also dose-dependently attenuated HC-induced caspase-3 activity in vitro. Our in vivo studies revealed that intracerebroventricular (i.c.v.) pre-administration of Rg(3) significantly and dose-dependently reduced i.c.v. HC-induced hippocampal damage in rats. To examine the mechanisms underlying the in vitro and in vivo neuroprotective effects of Rg(3) against HC-induced hippocampal excitotoxicity, we examined the effect of Rg(3) on HC-induced intracellular Ca(2+) elevations in cultured hippocampal cells and found that Rg(3) treatment dose-dependently inhibited HC-induced intracellular Ca(2+) elevation, with an IC(50) value of 41.5+/-17.5 muM. In addition, Rg(3) treatment dose-dependently inhibited HC-induced currents in Xenopus oocytes expressing the NMDA receptor, with an IC(50) of 47.3+/-14.2 muM. These results collectively indicate that Rg(3)-induced neuroprotection against HC in rat hippocampus might be achieved via inhibition of HC-mediated NMDA receptor activation.
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PMID:Neuroprotective effects of ginsenoside Rg3 against homocysteine-induced excitotoxicity in rat hippocampus. 1723 31

Huntingtin-interacting protein 1 (HIP1) is an endocytic adaptor protein that plays a role in clathrin-mediated endocytosis and the ligand-induced internalization of AMPA receptors (AMPARs) (Metzler et al., 2003). In the present study, we investigated the role of HIP1 in NMDA receptor (NMDAR) function by analyzing NMDA-dependent transport and NMDA-induced excitotoxicity in neurons from HIP1-/- mice. HIP1 colocalizes with NMDARs in hippocampal and cortical neurons and affinity purifies with NMDARs by GST (glutathione S-transferase) pull down and coimmunoprecipitation. A profound decrease in NMDA-induced AMPAR internalization of 75% occurs in neurons from HIP1-/- mice compared with wild type, using a quantitative single-cell-based internalization assay. This defect in NMDA-dependent removal of surface AMPARs is in agreement with the observed defect in long-term depression induction in hippocampal brain slices of HIP1-/- mice and supports a role of HIP1 in AMPAR internalization in vivo. HIP1-/- neurons are partially protected from NMDA-induced excitotoxicity as assessed by LDH (lactate dehydrogenase) release, TUNEL (terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick end labeling) and caspase-3 activation assays, which points to a role of HIP1 in NMDA-induced cell death. Interestingly, phosphorylation of Akt and its substrate huntingtin (htt) decreases during NMDA-induced excitotoxicity by 48 and 31%, respectively. This decrease is significantly modulated by HIP1, resulting in 94 and 48% changes in P-Akt and P-htt levels in HIP1-/- neurons, respectively. In summary, we have shown that HIP1 influences important NMDAR functions and that both HIP1 and htt participate in NMDA-induced cell death. These findings may provide novel insights into the cellular mechanisms underlying enhanced NMDA-induced excitotoxicity in Huntington's disease.
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PMID:NMDA receptor function and NMDA receptor-dependent phosphorylation of huntingtin is altered by the endocytic protein HIP1. 1732 27

We have previously shown that the co-localization of neuronal nitric oxide synthase (nNOS) with neurofilament (NF) aggregates in motor neurons derived from transgenic mice over-expressing the human low molecular weight NF protein (hNFL+/+) is associated with a deregulation of calcium influx via the N-methyl-d-aspartate (NMDA) receptor, resulting in apoptosis. Because the absence of the GluR2 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoazolepropionic acid (AMPA) receptor confers calcium permeability and has been implicated in the process of excitotoxicity in ALS, we have examined the role of the AMPA receptor in this model. GluR2 protein expression and mRNA were examined in hNFL+/+ and wild-type motor neurons (wt). Live cell calcium imaging was performed using Oregon-Green Bapta and Fura-2 calcium dyes. For apoptotic studies, neurons were treated with glutamate, with or without glutamate receptor antagonists [6-cyano-7-nitroquinoxaline-2, 3-dione (CNQX) or (+)-5-methyl-10, 11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801)] and examined for active caspase-3 or phospholipid inversion. We observed that although both GluR2 mRNA and protein levels were decreased in hNFL+/+ motor neurons compared to wt, there was no appreciable calcium influx via the AMPA receptor. These studies demonstrate that calcium mediated excitotoxicity in NF aggregate-bearing neurons is NMDA receptor dependant.
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PMID:Calcium mediated excitotoxicity in neurofilament aggregate-bearing neurons in vitro is NMDA receptor dependant. 1736 87

Previous work has demonstrated that the surface glycoprotein (gp120) of human immunodeficiency virus-1 (HIV-1) can induce damage and apoptosis of neurons both in vitro and in vivo. In this report, we provide evidence that double-stranded RNA-activated protein kinase (PKR), a stress kinase, is involved in HIV/gp120-associated neurodegeneration. In cultures of mixed cortical cells, HIV/gp120 increased the protein level of PKR. Additionally, PKR was phosphorylated in neurons but not glia after exposure to gp120. The use of two independent pharmacological inhibitors of PKR activity abrogated neuronal cell death induced by gp120. Cortical neurons from PKR knock-out mice were significantly protected from neurotoxicity induced by gp120, further validating the pivotal proapoptotic function of PKR. gp120-induced phosphorylated PKR localized prominently to neuronal nuclei; PKR inhibition or the NMDA receptor antagonist MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine maleate] abrogated this effect. PKR inactivation also inhibited gp120-induced caspase-3 activation, consistent with its neuroprotective effect. Finally, brain tissue from individuals diagnosed with HIV-associated dementia (HAD), but not HIV infection alone, contained the activated form of PKR, which localized predominantly to neuronal nuclei. Together, these results identify PKR as a critical mediator of gp120 neurotoxicity, suggesting that activation of PKR contributes to the neuronal injury and cell death observed in HAD.
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PMID:Human immunodeficiency virus-1/surface glycoprotein 120 induces apoptosis through RNA-activated protein kinase signaling in neurons. 1792 46

A massive neuronal loss during early postnatal development has been well documented in the murine cerebral cortex, but the factors that drive cells into apoptosis are largely unknown. The role of neuronal activity in developmental apoptosis was studied in organotypic neocortical slice cultures of newborn mice. Multielectrode array and whole-cell patch-clamp recordings revealed spontaneous network activity characterized by synchronized burst discharges, which could be blocked by tetrodotoxin and ionotropic glutamate receptor antagonists. The identical neuropharmacological manipulations also caused a significant increase in the number of apoptotic neurons as early as 6 h after the start of drug treatment. Moreover, inhibition of the NMDA receptor subunit NR2A or NR2B induced a differential short-term versus delayed increase in the apoptosis rate, respectively. Activation of L-type, voltage-dependent calcium channels was neuroprotective and could prevent activity-dependent apoptosis during NMDA receptor blockade. Furthermore, this effect involved phosphorylation of cAMP response element-binding protein and activation of the tropomyosin-related kinase (Trk) receptors. Inhibition of electrical synapses and blockade of ionotropic gamma-aminobutyric acid receptors induced specific changes in spontaneous electrical activity patterns, which caused an increase in caspase-3-dependent cell death. Our results demonstrate that synchronized spontaneous network bursts activating ionotropic glutamate receptors promote neuronal survival in the neonatal mouse cerebral cortex.
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PMID:Activity-dependent regulation of neuronal apoptosis in neonatal mouse cerebral cortex. 1796 27

Memantine, a clinically used N-methyl-D-aspartate (NMDA)-receptor antagonist, has been shown to prevent apoptotic neuronal damage connected with the over-activity of NMDA receptors. In the present study, we examined the effect of memantine on staurosporine-, salsolinol- and doxorubicin-induced apoptosis in the SH-SY5Y cell line which does not possess functional NMDA receptors. Electrophysiological recordings and toxicity studies showed no response to NMDA-evoked currents in this cell line, irrespective of the stage of its neuronal differentiation. Memantine (0.1-2 microM) attenuated staurosporine-induced apoptosis as evidenced by reversal of the changes in mitochondrial membrane potential (DeltaPsi(m)) and decreased caspase-3 activity, lactate dehydrogenase (LDH) release and DNA fragmentation. Wortmannin (10 nM) and LY 294002 (10 microM) (inhibitors of phosphatidylinositol-3-kinase, PI3-K) reversed the inhibitory effect of memantine on the staurosporine-induced LDH release, suggesting that the PI3-K/Akt prosurvival pathway is a possible target for antiapoptotic action of memantine. Memantine at low micromolar concentrations also attenuated salsolinol- and doxorubicin-induced LDH release and DNA fragmentation, but only in the case of salsolinol was this effect accompanied by a decrease in caspase-3 activity. The present data indicate that memantine attenuates the toxic effects of various proapoptotic agents and the cytoprotective effect of memantine does not seem to be connected with its action on NMDA receptor but rather with its influence on intracellular pathways engaged in cellular survival/apoptotic processes.
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PMID:The attenuating effect of memantine on staurosporine-, salsolinol- and doxorubicin-induced apoptosis in human neuroblastoma SH-SY5Y cells. 1799 85

Agonists at A(1) receptors and antagonists at A(2A) receptors are known to be neuroprotective against excitotoxicity. We set out to clarify the mechanisms involved by studying interactions between adenosine receptor ligands and endogenous glutamate in cultures of rat cerebellar granule neurons (CGNs). Glutamate and the selective agonist N-methyl-D: -aspartate (NMDA), applied to CGNs at 9 div (days in vitro), both induced cell death in a concentration-dependent manner, which was attenuated by treatment with the NMDA receptor antagonists dizocilpine, D: -2-amino-5-phosphono-pentanoic acid (D: -AP5) or kynurenic acid (KYA), but not by the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Glutamate toxicity was reduced in the presence of all of the following: cyclosporin A (CsA), a blocker of the membrane permeability transition pore, the caspase-3 inhibitor, benzyloxycarbonyl-Asp(OMe)-Glu(OMe)-Val-Asp(OMe)-fluoromethylketone (Z-DEVD-fmk), the poly (ADP-ribose) polymerase (PARP-1) inhibitor 3,4-dihydro-5-[4-(1-piperidinyl)butoxyl]-1(2H)-isoquinolinone (DPQ), and nicotinamide. This is indicative of involvement of both apoptotic and necrotic processes. The A(1) receptor agonist, N (6)-cyclopentyladenosine (CPA), and the A(2A) receptor antagonist 4-(2-[7-amino-2-[2-furyl][1,2,4]triazolo[2,3-a][1,3,5]triazo-5-yl-amino]ethyl)phenol (ZM241385) afforded significant protection, while the A(1) receptor blocker 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) and the A(2A) receptor agonist 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxyamidoadenosine (CGS21680) had no effect. These results confirm that glutamate-induced neurotoxicity in CGNs is mainly via the NMDA receptor, but show that a form of cell death which exhibits aspects of both apoptosis and necrosis is involved. The protective activity of A(1) receptor activation or A(2A) receptor blockade occurs against this mixed profile of cell death, and appears not to involve the selective inhibition of classical apoptotic or necrotic cascades.
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PMID:Adenosine receptor ligands protect against a combination of apoptotic and necrotic cell death in cerebellar granule neurons. 1804 Jun 69

Transient postnatal NMDA receptor blockade by phencyclidine (PCP), ketamine, or MK-801 induces developmental neuroapoptosis and adult behavioral deficits, which resemble abnormal human behaviors typically present in schizophrenia. This study tested the hypothesis that PCP-induced developmental apoptosis causes a specific deficit of GABAergic interneurons containing parvalbumin (PV), calretinin (CR), or calbindin (CB). Young adult (PND56) rats that were given a single dose of PCP (10 mg/kg) on PND7 exhibited no densitometric change of either CR or CB neurons in any brain region studied, but demonstrated a selective deficit of PV-containing neurons in the superficial layers (II-IV) of the primary somatosensory (S1), motor (M), and retrosplenial cortices, but not in the striatum (CPu) or hippocampus. Further, CR and CB neurons, which were expressed at the time of PCP administration, showed no colocalization with cellular markers of apoptosis (terminal dUTP nick-end labeling (TUNEL) of broken DNA or cleaved caspase-3), indicating that CR- and CB-containing neurons were protected from the toxic effect of PCP and survived into adulthood. This suggests that the deletion of PV neurons occurred during development, but cleaved caspase-3 showed no colocalization with BrdU, a specific marker of S-phase proliferation. These data suggest that the loss of PV-containing neurons was not due to an effect of PCP on proliferating neurons, but rather an effect on post-mitotic neurons. The developmental dependence and neuronal specificity of this effect of PCP provides further evidence that this model may be valuable in exploring the pathophysiology of schizophrenia.
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PMID:Postnatal phencyclidine administration selectively reduces adult cortical parvalbumin-containing interneurons. 1805 37

In mouse cerebellar granule neurons (CGNs) the marine neurotoxin domoic acid (DomA) induces neuronal cell death, either by apoptosis or by necrosis, depending on its concentration, with apoptotic damage predominating in response to low concentrations (100 nM). DomA-induced apoptosis is due to selective activation of AMPA/kainate receptors, and is mediated by DomA-induced oxidative stress, leading to mitochondrial dysfunction and activation of caspase-3. The p38 MAP kinase and the c-Jun NH2-terminal protein kinase (JNK) have been shown to be preferentially activated by oxidative stress. Here we report that DomA increases p38 MAP kinase and JNK phosphorylation, and that this effect is more pronounced in CGNs from Gclm (-/-) mice, which lack the modifier subunit of glutamate-cysteine ligase, have very low glutathione (GSH) levels, and are more sensitive to DomA-induced apoptosis than CGNs from wild-type mice. The increased phosphorylation of JNK and p38 kinase was paralleled by a decreased phosphorylation of Erk 1/2. The AMPA/kainate receptor antagonist NBQX, but not the NMDA receptor antagonist MK-801, prevents DomA-induced activation of p38 and JNK kinases. Several antioxidants (GSH ethyl ester, catalase and phenylbutylnitrone) also prevent DomA-induced phosphorylation of JNK and p38 MAP kinases. Inhibitors of p38 (SB203580) and of JNK (SP600125) antagonize DomA-induced apoptosis. These results indicate the importance of oxidative stress-activated JNK and p38 MAP kinase pathways in DomA-induced apoptosis in CGNs.
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PMID:Apoptosis induced by domoic acid in mouse cerebellar granule neurons involves activation of p38 and JNK MAP kinases. 1816 2

The cell death cascades in different brain regions namely hippocampus and frontal cortex of rats fed with 10% (v/v) ethanol for 12 weeks, was examined. After Western blotting, different cell death associated proteins displayed differential activation in the two regions observed. In hippocampus, activated caspase-3 and caspase-7 resulted in subsequent cleavage of poly(ADP-ribose) polymerase-1 (PARP-1). Cytochrome c release to cytosol and apoptosis inducing factor (AIF) translocation to nucleus was marginal. B-cell leukemia/lymphoma-2 (Bcl-2) translocation to cytosol was significant whereas Bcl-2-associated X protein (Bax) and Bcl-associated death protein (Bad) were largely located in cytosol. Further, upregulation of N-methyl D-aspartate receptor subunit 1 (NMDAR1), N-methyl D-aspartate receptor subunit 2B (NMDAR2B), N-methyl D-aspartate receptor subunit 2C (NMDAR2C) and activation of calpains were observed. In frontal cortex, caspase-3 activation, cleavage of PARP-1 and nuclear translocation of AIF were more pronounced. Moreover, cytochrome c release to cytosol, Bcl-2 translocation to cytosol was evident. However, levels of Bax, Bad, NMDA receptor subunits, and calpains were unaffected. Apoptosis was further substantiated by in situ staining for terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL). Results of the current study revealed that frontal cortex exhibits a higher level of ethanol-induced apoptosis relative to hippocampus. DNA polymerase beta assay and immunoblot showed significant loss in base excision repair in ethanol treated group.
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PMID:Cell death is associated with reduced base excision repair during chronic alcohol administration in adult rat brain. 1825 62


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