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)

Accumulation of the neurotoxic amyloid beta-peptide (Abeta) in the brain is a hallmark of Alzheimer's disease (AD). Several synthetic Abeta peptides have been used to study the mechanisms of toxicity. Here, we sought to establish comparability between two commonly used Abeta peptides Abeta1-42 and Abeta25-35 on an in vitro model of Abeta toxicity. For this purpose we used organotypic slice cultures of rat hippocampus and observed that both Abeta peptides caused similar toxic effects regarding to propidium iodide uptake and caspase-3 activation. In addition, we also did not observe any effect of both peptides on Akt and PTEN phosphorylation; otherwise the phosphorylation of GSK-3beta was increased. Although further studies are necessary for understanding mechanisms underlying Abeta peptide toxicity, our results provide strong evidence that Abeta1-42 and the Abeta25-35 peptides induce neural injury in a similar pattern and that Abeta25-35 is a convenient tool for the investigation of neurotoxic mechanisms involved in AD.
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PMID:A comparative study of beta-amyloid peptides Abeta1-42 and Abeta25-35 toxicity in organotypic hippocampal slice cultures. 1868 32

Epidemiologic studies inclusively indicate that "unhealthy" dietary fat intake is one of the potential risk factors for cancer. In dietary fat, there are two types of polyunsaturated fatty acids (PUFA), omega-3 (n-3) and omega-6 (n-6). Numerous studies support that the ratio of n-6/n-3 affects tumorigenesis. It was reported that adenoviral transfer of the fat-1 gene, which converts n-6 to n-3, into breast and lung cancer cells had an antitumor effect in vitro. However, the effects of the fat-1 gene expression on tumor growth in vivo have not been studied and the mechanisms remain unclear. Accordingly, prostate cancer DU145 and PC3 cells were transfected with either the fat-1 gene or a control vector. The cells that expressed the fat-1 gene had a lower n-6/n-3 PUFA ratio compared with the cells that expressed the control vector. The fat-1 gene expression significantly inhibited prostate cancer cell proliferation and invasion in vitro. The fat-1 and control vector-transfected prostate cancer cells were s.c. implanted into severe combined immunodeficient mice for 6 weeks. The fat-1 gene expression significantly diminished tumor growth in vivo, but the control vector had no effect. Finally, we evaluated signaling pathways that may be important for fat-1 gene function. Administration of n-3 PUFA induced caspase-3-mediated prostate cancer cell apoptosis in vitro. The fat-1 gene expression inhibited prostate cancer cell proliferation via reduction of GSK-3beta phosphorylation and subsequent down-regulation of both beta-catenin and cyclin D1. These results suggest that fat-1 gene transfer directly into tumor cells could be used as a novel therapeutic approach.
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PMID:Expression of the fat-1 gene diminishes prostate cancer growth in vivo through enhancing apoptosis and inhibiting GSK-3 beta phosphorylation. 1885 24

Hepatocellular carcinoma (HCC) displays a striking resistance to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Therefore, the characterization of pharmacological agents that overcome this resistance may provide new therapeutic modalities for HCC. Here, we examined whether glycogen synthase kinase-3 (GSK-3) inhibitors could restore TRAIL sensitivity in hepatoma cells. To this aim, the effects of two GSK-3 inhibitors, lithium and SB-415286, were analyzed on TRAIL apoptotic signaling in human hepatoma cell lines in comparison with normal hepatocytes. We observed that both inhibitors sensitized hepatoma cells, but not normal hepatocytes, to TRAIL-induced apoptosis by enhancing caspase-8 activity and the downstream recruitment of the mitochondrial machinery. GSK-3 inhibitors also stabilized p53 and the down-regulation of p53 by RNA interference abolished the sensitizing effect of lithium on caspase-3 activation. Concomitantly, GSK-3 inhibitors strongly activated c-Jun N-terminal kinases (JNKs). The pharmacological inhibition of JNKs with AS601245 or SP600125 resulted in an earlier and stronger induction of apoptosis indicating that activated JNKs transduced protective signals and provided an anti-apoptotic balance to the pro-apoptotic effects of GSK-3 inhibitors. These findings demonstrate that GSK-3 exerts a negative and complex constraint on TRAIL apoptotic signaling in hepatoma cells, which can be greatly alleviated by GSK-3 inhibitors. Therefore, GSK-3 inhibitors may open new perspectives to enhance the anti-tumor activity of TRAIL in HCC.
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PMID:Glycogen synthase kinase-3 inhibitors augment TRAIL-induced apoptotic death in human hepatoma cells. 1893 43

Postconditioning (PostC) may limit mitochondrial damage and apoptotic signaling. We studied markers of apoptosis and mitochondrial protection in isolated rat hearts, which underwent a) perfusion without ischemia (Sham), b) 30-min ischemia (I) plus 2-hour reperfusion (R), or c) PostC protocol (5 intermittent cycles of 10-s reperfusion and 10-s ischemia immediately after the 30-min ischemia). Markers were studied in cytosolic (CF) and/or mitochondrial (MF) fractions. In CF, while pro-apoptotic factors (cytochrome c and caspase-3) were reduced, the anti-apoptotic markers (Bcl-2 and Pim-1) were increased by PostC, compared to the I/R group. Accordingly, phospho-GSK-3beta and Bcl-2 levels increased in mitochondria of PostC group. Moreover, I/R reduced the level of mitochondrial structural protein (HSP-60) in MF and increased in CF, thus suggesting mitochondrial damage and HSP-60 release in cytosol, which were prevented by PostC. Electron microscopy confirmed that I/R markedly damaged cristae and mitochondrial membranes; damage was markedly reduced by PostC. Finally, total connexin-43 (Cx43) levels were reduced in the CF of the I/R group, whereas phospho-Cx43 level resulted in higher levels in the MF of the I/R group than the Sham group. PostC limited the I/R-induced increase of mitochondrial phospho-Cx43. Data suggest that PostC i) increases the levels of anti-apoptotic markers, including the cardioprotective kinase Pim-1, ii) decreases the pro-apoptotic markers, e.g. cytochrome c, iii) preserves the mitochondrial structure, and iv) limits the migration of phospho-Cx43 to mitochondria.
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PMID:Postconditioning induces an anti-apoptotic effect and preserves mitochondrial integrity in isolated rat hearts. 2970 30

In this study we report the coupling of nucleotide receptors to GSK-3 signalling, a relevant survival pathway in cerebellar granule neurons. P2X(7) agonist BzATP induced a 3-4-fold increase in GSK-3 phosphorylation, which is reported to be associated with the catalytic activity inhibition. This effect was dependent on extracellular calcium and PKC, and independent of PI3-K (phosphatidyl-inositol-3-kinase)/Akt, the main survival route of neurotrophins. BzATP also prevented the apoptosis of granule neurons induced by the pharmacological inhibition of the PI3-K signalling. Both effects, BzATP-mediated GSK-3 phosphorylation and neuroprotection, were abolished by P2X(7) receptor antagonists, BBG, PPADS and A-438079. We found that BzATP prevented the progressive GSK-3 dephosphorylation and caspase-3 activation occurring under conditions of sustained PI3-K inhibition. These results reveal that P2X(7) receptor activation could provide a relevant survival route alternative to classical neurotrophic factors.
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PMID:P2X7 nucleotide receptor is coupled to GSK-3 inhibition and neuroprotection in cerebellar granule neurons. 1938 92

Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses signaling through protein kinase C (PKC)-beta and the phosphatidylinositol 3-kinase/AKT pathways. We preclinically evaluated enzastaurin alone and in combination with gemcitabine for transitional cell cancer (TCC). Immunohistochemistry (IHC) was done on 105 human samples from a microarray to show the expression of PKC-beta. The preclinical antitumor activity of enzastaurin and gemcitabine as single agents and in combination against aggressive human -lines (-SUP and 5637) and murine subcutaneous xenografts bearing 5637 cells was determined. Western Blot was done on tumor cells in vitro to detect signaling through PKC-beta, GSK-3beta, and AKT. The effect on cell migration was determined in vitro. Modulation of proliferation (Ki-67), apoptosis (cleaved caspase-3), and angiogenesis (CD31) in vivo was determined by IHC. IHC done on human TCC samples from a microarray showed the expression of PKC-beta in 33% of tumors. Enzastaurin induced significant apoptosis and inhibited proliferation in vitro at low micromolar concentrations. The in vitro inhibitory activity of combination enzastaurin and gemcitabine by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay seemed synergistic. Western Blotting revealed down-regulation of Akt, PKC-beta, and GSK-3 beta phosphorylation. Enzastaurin inhibited migration at an earlier time point independent of antiproliferative activity. Combination therapy had significantly superior antitumor activity in murine xenografts compared with untreated controls, whereas single agents did not. IHC showed reduced Ki-67 and CD31 and increased cleaved caspase-3 with combination therapy compared with controls. Enzastaurin showed preclinical antitumor activity against human TCC and enhanced the activity of gemcitabine.
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PMID:Enzastaurin shows preclinical antitumor activity against human transitional cell carcinoma and enhances the activity of gemcitabine. 1950 73

The purpose of this study was to assess the short- and long-term cardioprotective effects of darbepoetin-alpha (DA) in a rat myocardial ischemia and reperfusion model and to investigate the signaling pathway through which DA limits cardiomyocytes apoptosis. Rats were subjected to 40 minutes of coronary artery ligation followed by 72 hours or 4 weeks reperfusion and received either DA (3 or 30 microg/kg, DA3 and D30 groups) or vehicle (control) prior to ischemia. In the DA groups reperfused for 72 hours, left ventricular shortening fraction and left ventricular ejection fraction were higher than that in the control rats (P < 0.05), in agreement with a smaller left ventricular (LV) infarct size. DA treatment activated the JAK2/Akt signaling pathway, lowered cleaved caspase-3, and increased both phosphorylated-Bad and phosphorylated-GSK-3beta proteins. This was consistent with the decrease of reactive oxygen species production and the lowered binding of Bad to Bcl-xL and Bcl-2 in a DA30 group of rats. Similarly, in the DA-4-week group, LV function was greater compared to the control. Histology alterations implicated lower LV cardiac fibrosis and greater capillary density; furthermore, both Bcl-xL and Bcl-2 were upregulated. In conclusion, DA afforded short- and long-term cardioprotective effects. Antiapoptotic effects, through the activation of Akt that regulates the Bcl-2 family proteins and activates GSK-3beta, are central in the DA cardioprotective mechanism.
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PMID:Short- and long-term cardioprotective effect of darbepoetin-alpha: role of Bcl-2 family proteins. 1959 69

Intermedin (IMD) is a novel member of the calcitonin/calcitonin gene-related peptide family. We investigated the cardioprotective mechanism of IMD(1-53) in the in vivo rat model of myocardial ischemia/reperfusion (I/R) injury and in vitro primary neonatal cardiomyocyte model of hypoxia/reoxygenation (H/R). Myocardial infarct size was measured by 2,3,5-triphenyl tetrazolium chloride staining. Cardiomyocyte viability was determined by trypan blue staining, cell injury by lactate dehydrogenase (LDH) leakage, and cardiomyocyte apoptosis by terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling assay, Hoechst staining, gel electrophoresis and caspase 3 activity. The translocation of mitochondrial cytochrome c of myocardia and expression of apoptosis-related factors Bcl-2 and Bax, phosphorylated Akt and phosphorylated GSK-3beta were determined by western blot analysis. IMD(1-53) (20 nmol/kg) limited the myocardial infarct size in rats with I/R; the infarct size was decreased by 54%, the apoptotic index by 30%, and caspase 3 activity by 32%; and the translocation of cytochrome c from mitochondria to cytosol was attenuated. IMD(1-53) increased the mRNA and protein expression of Bcl-2 and ratio of Bcl-2 to Bax by 81 and 261%, respectively. IMD(1-53) (1 x 10(-7) mol/L) inhibited the H/R effect in cardiomyocytes by reducing cell death by 43% and LDH leakage by 16%; diminishing cellular apoptosis; decreasing caspase 3 activity by 50%; and increasing the phosphorylated Akt and GSK-3beta by 41 and 90%, respectively. The cytoprotection of IMD(1-53) was abolished with LY294002, a PI3K inhibitor. In conclusion, IMD(1-53) exerts cardioprotective effect against myocardial I/R injury through the activation of the Akt/GSK-3beta signaling pathway to inhibit mitochondria-mediated myocardial apoptosis.
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PMID:Activation of Akt/GSK-3beta signaling pathway is involved in intermedin(1-53) protection against myocardial apoptosis induced by ischemia/reperfusion. 1963 12

The tripeptide thyrotropin-releasing hormone (TRH, pGlu-His-Pro-NH2) has been shown to possess neuroprotective activity in in vitro and in vivo models. Since its potential utility is limited by relatively rapid metabolism, metabolically stabilized analogues have been constructed. In the present study we investigated the influence of TRH and its three stable analogues: Montirelin (MON, CG-3703), RGH-2202 (L-6-keto-piperidine-2carbonyl-l-leucyl-l-prolinamide) and Z-TRH (N-carbobenzyloxy-pGlutamyl-Histydyl-Proline) in various models of mouse cortical neuronal cell injury. Twenty four hour pre-treatment with TRH and its analogues in low micromolar concentrations attenuated the neuronal cell death evoked by excitatory amino acids (EAAs: glutamate, NMDA, kainate, quisqualate) and hydrogen peroxide. All the peptides showed neuroprotective action on staurosporine (St)-evoked apoptotic neuronal cell death, but this effect was caspase-3 independent. Interestingly, in mixed neuronal-glial cell preparations only MON decreased St- and glutamate-evoked neurotoxicity. None of the peptides inhibited the doxorubicin- and lactacystin-induced neuronal cortical cell death, agents acting via activation of death receptor (FAS) or inhibition of proteasome function, respectively. Furthermore, we found that neither inhibitors of PI3-K (wortmannin, LY 294002) nor MAPK/ERK1/2 (PD 098059, U 0126) were able to inhibit neuroprotective properties of TRH and MON in St model of apoptosis. The protection mediated by TRH and MON it that model was also not connected with influence of peptides on the pro-apoptotic GSK-3beta and JNK protein kinase expression and activity. Further studies showed that calpains, calcium-activated proteases were induced by Glu, but not by St in cortical neurons. Moreover, the Glu-evoked increase in spectrin alpha II cleavage product induced by calpains was blocked by TRH. The obtained data showed that the potency of TRH and its analogues in inhibiting EAAs- and H(2)O(2)-induced neuronal cell death from the highest to lowest activity was: MON>TRH>Z-TRH>RHG. Interestingly, all peptides were active against St-induced apoptosis, however, on concentration basis MON was far more potent than the other peptides. None of the peptides inhibited Dox- and LC-evoked apoptotic cell death. Additionally, the data exclude potential role of pro-survival (PI3-K/Akt and MAPK/ERK1/2) and pro-apoptotic (GSK-3beta and JNK) pathways in neuroprotective effects of TRH and its analogues on St-induced neuronal apoptosis. Moreover, the results point to involvement of the inhibition of calpains in the TRH neuroprotective effect in Glu model of neuronal cell death.
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PMID:Effects of TRH and its analogues on primary cortical neuronal cell damage induced by various excitotoxic, necrotic and apoptotic agents. 1966 92

Intermedin (IMD) is a novel member of the calcitonin/calcitonin gene-related peptide family. We investigated the cardioprotective mechanism of IMD(1-53) in the in vivo rat model of myocardial ischemia/reperfusion (I/R) injury and in vitro primary neonatal cardiomyocyte model of hypoxia/reoxygenation (H/R). Myocardial infarct size was measured by 2,3,5-triphenyl tetrazolium chloride staining. Cardiomyocyte viability was determined by trypan blue staining, cell injury by lactate dehydrogenase (LDH) leakage, and cardiomyocyte apoptosis by terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling assay, Hoechst staining, gel electrophoresis and caspase 3 activity. The translocation of mitochondrial cytochrome c of myocardia and expression of apoptosis-related factors Bcl-2 and Bax, phosphorylated Akt and phosphorylated GSK-3beta were determined by western blot analysis. IMD(1-53) (20 nmol/kg) limited the myocardial infarct size in rats with I/R; the infarct size was decreased by 54%, the apoptotic index by 30%, and caspase 3 activity by 32%; and the translocation of cytochrome c from mitochondria to cytosol was attenuated. IMD(1-53) increased the mRNA and protein expression of Bcl-2 and ratio of Bcl-2 to Bax by 81 and 261%, respectively. IMD(1-53) (1 x 10(-7) mol/L) inhibited the H/R effect in cardiomyocytes by reducing cell death by 43% and LDH leakage by 16%; diminishing cellular apoptosis; decreasing caspase 3 activity by 50%; and increasing the phosphorylated Akt and GSK-3beta by 41 and 90%, respectively. The cytoprotection of IMD(1-53) was abolished with LY294002, a PI3K inhibitor. In conclusion, IMD(1-53) exerts cardioprotective effect against myocardial I/R injury through the activation of the Akt/GSK-3beta signaling pathway to inhibit mitochondria-mediated myocardial apoptosis.
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PMID:Activation of Akt/GSK-3beta signaling pathway is involved in intermedin(1-53) protection against myocardial apoptosis induced by ischemia/reperfusion. 1975 65


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