Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10415 (Bcl-2)
 33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study examined the growth inhibitory effects of the structurally related beta-diketones compounds in human cancer cells. Here, we report that 1-(2-hydroxy-5-methylphenyl)-3-phenyl-1,3-propanedione (HMDB) induces growth inhibition of human cancer cells and induction of apoptosis in A431 cells through modulation of mitochondrial functions regulated by reactive oxygen species (ROS). ROS generation occurs in the early stages of HMDB-induced apoptosis, preceding cytochrome c release, caspase activation, and DNA fragmentation. The changes occurred after single breaks in DNA were detected, suggesting that HMDB induced irreparable DNA damage, which in turn triggered the process of apoptosis. Up-regulation of Bad and p21; down-regulation of Bcl-2, Bcl-XL, Bid, p53, and fatty acid synthase; and cleavage of Bax were found in HMDB-treated A431 cells. Glutathione and N-acetylcysteine (NAC) suppress HMDB-induced apoptosis. HMDB markedly enhanced growth arrest DNA damage inducible gene 153 (GADD153) mRNA and protein in a time- and concentration-dependent manner. NAC prevented up-regulation of GADD153 mRNA expression caused by HMDB. These findings suggest that HMDB creates an oxidative cellular environment that induces DNA damage and GADD153 gene activation, which in turn helps trigger apoptosis in A431 cells.
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PMID:Induction of apoptosis by 1-(2-hydroxy-5-methylphenyl)-3-phenyl-1,3-propanedione through reactive oxygen species production, GADD153 expression, and caspases activation in human epidermoid carcinoma cells. 1627

Antisense technology was successfully employed to selectively reduce the expression of Bcl-2 in U937 cells, while leaving their redox status intact. These cells displayed enhanced sensitivity to mitochondrial permeability transition (MPT)-dependent apoptosis induced by arsenite and underwent a rapid, MPT-dependent necrotic response after exposure to otherwise nontoxic concentrations of peroxynitrite. Several lines of evidence consistently indicate that these low concentrations of peroxynitrite nevertheless commit cells to MPT, which is, however, prevented by a survival signaling in which arachidonic acid, protein kinase Calpha (PKCalpha), and Bcl-2 are sequentially involved. Bcl-2, however, was not the direct target of PKCalpha but most likely Bad, a protein involved in the regulation of Bcl-2 activity via heterodimerization. Further studies revealed that Bcl-2 does not afford protection in cells challenged with intrinsically toxic concentrations of peroxynitrite. This was due to depletion of GSH, an event leading to loss of the anti-MPT function of Bcl-2. Collectively, these results demonstrate a role of Bcl-2 in monocyte survival signaling preventing MPT-dependent necrosis induced by peroxynitrite, and provide an explanation for the reported observation that Bcl-2 fails to prevent necrosis mediated by intrinsically toxic levels of peroxynitrite.
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PMID:Role of Bcl-2 in the arachidonate-mediated survival signaling preventing mitochondrial permeability transition-dependent U937 cell necrosis induced by peroxynitrite. 1629 89

We have investigated whether maternal obstructive cholestasis during pregnancy (OCP) causes oxidative stress and apoptosis in rat placenta and whether treatment with ursodeoxycholic acid (UDCA, i.g., 60 microg/100 g b.wt./day, following complete biliary obstruction on day 14 of pregnancy) has protective effects on this organ. In rats with OCP, increased (15-fold) serum bile acid concentrations (BAs) together with signs of placental oxidative stress (lipid peroxidation and protein carbonylation) were found. The latter were partly prevented by UDCA, even though hypercholanemia was not corrected. Some elements of the antioxidant system (total glutathione content, GSH/GSSG ratio and catalase, glutathione peroxidase, and glutathione-S-transferase--but not glutathione reductase--activities) were impaired in placentas from the OCP group. UDCA treatment partly prevented changes in the antioxidant system. OCP induced an increase in Bax-alpha/Bcl-2 mRNA ratio, as determined by real-time quantitative PCR, suggesting enhanced susceptibility to apoptosis activation through the mitochondria-mediated pathway. Accordingly, the activity of caspase-3, but not caspase-8, was increased in OCP placentas, in which DNA-ladder analysis and TUNEL confirmed the existence of apoptosis. UDCA prevented changes in the Bax-alpha/Bcl-2 mRNA ratio and caspase-3 activity. In conclusion, OCP causes oxidative stress and apoptosis in rat placenta, which can be prevented by treatment with UDCA.
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PMID:Maternal cholestasis induces placental oxidative stress and apoptosis. Protective effect of ursodeoxycholic acid. 1631 35

Bcl-2 is best known for its anti-apoptotic function in a wide variety of cell types. The objective of this study was to investigate the effects of bcl-2 on the types of cell demise in the HeLa/bcl-2 cells induced by H2O2. The HeLa cell expressed stably bcl-2 was established and defined as the HeLa/bcl-2 cell strain, while the cell transfected with the empty expression vector was defined as the HeLa/vector cell strain. MTT assay revealed that the HeLa/bcl-2 cells showed a shorter life span. BrdU incorporation assay indicated that the bcl-2 exerted anti-demise effect on the HeLa/bcl-2 cells at the low concentration of H2O2. However, at the high concentration of H2O2, the death of the HeLa/bcl-2 cells was more than that of the HeLa/vector cells. The flow cytometry demonstrated that H2O2 mainly induced apoptosis in the HeLa/vector cells and elicited necrosis in the HeLa/bcl-2 cells. The addition of celecoxib to the cells treated by H2O2 could increase apoptosis in the HeLa/vector cells and convert necrosis into apoptosis in the HeLa/bcl-2 cells. The higher levels of cellular free radical and GSH were found in the HeLa/bcl-2 cells, but not in the HeLa/vector cells. With 200 microM H2O2 challenge for 48 h, the level of the cellular free radical was increased in the both strains, while the level of the GSH was decreased in the both strains. Celecoxib could reverse the difference between the both strains led by H2O2. Western blotting showed that the expression of COX-2 was always higher in the HeLa/bcl-2 cells than in the HeLa/vector cells under the both of treated and untreated with H2O2, while the level of COX-1 was relative stable in the both strains. These results suggested that the crosstalk between the bcl-2 and the COX-2 pathways could exist, the bcl-2 might up-regulate COX-2 to modify sensitivity to the types of demise in the HeLa/bcl-2 cell.
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PMID:Bcl-2 switches the type of demise from apoptosis to necrosis via cyclooxygenase-2 upregulation in HeLa cell induced by hydrogen peroxide. 1645 14

Pulse-treatment of U-937 human promonocytic cells with cadmium chloride followed by recovery caused caspase-9/caspase-3-dependent, caspase-8-independent apoptosis. However, pre-incubation with the glutathione (GSH)-suppressing agent DL-buthionine-(S,R)-sulfoximine (cadmium/BSO), or co-treatment with H2O2 (cadmium/H2O2), switched the mode of death to caspase-independent necrosis. The switch from apoptosis to necrosis did not involve gross alterations in Apaf-1 and pro-caspase-9 expression, nor inhibition of cytochrome c release from mitochondria. However, cadmium/H2O2-induced necrosis involved ATP depletion and was prevented by 3-aminobenzamide, while cadmium/BSO-induced necrosis was ATP independent. Pre-incubation with BSO increased the intracellular cadmium accumulation, while co-treatment with H2O2 did not. Both treatments caused intracellular peroxide over-accumulation and disruption of mitochondrial transmembrane potential (delta psi m). However, while post-treatment with N-acetyl-L-cysteine or butylated hydroxyanisole reduced the cadmium/BSO-mediated necrosis and delta psi m disruption, it did not reduce the effects of cadmium/H2O2. Bcl-2 over-expression, which reduced peroxide accumulation without affecting the intracellular GSH content, attenuated necrosis generation by cadmium/H2O2 but not by cadmium/BSO. By contrast, AIF suppression, which reduced peroxide accumulation and increased the GSH content, attenuated the toxicity of both treatments. These results unravel the existence of two different oxidation-mediated necrotic pathways in cadmium-treated cells, one of them resulting from ATP-dependent apoptosis blockade, and the other involving the concurrence of multiple regulatory factors.
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PMID:Regulation of apoptosis/necrosis execution in cadmium-treated human promonocytic cells under different forms of oxidative stress. 1653 69

The anti-cancer effects and possible mechanisms of the freshwater clam (Corbicula fluminea Muller) and its active compounds (FME) on cell viability in human leukemia HL-60 cells were investigated. This study demonstrated that FME was able to inhibit cell proliferation in a concentration- and time-dependent manner. Treatment with FME caused induction of caspase-2, caspase-3, caspase-6, caspase-8, and caspase-9 activity in a time-dependent manner, but not affect caspase-1 activity; it induced the proteolysis of DNA fragmentation factor (DFF-45) and poly(ADP-ribose) polymerase (PARP). Induction of cell death by FME was completely prevented by a pan-caspase inhibitor, Z-Val-Ala-Asp-fluoromethyl ketone (Z-VAD-FMK) and a caspase-2 inhibitor, Z-Val-Asp-Val-Ala-Asp-FMK (Z-VDVAD-FMK). Furthermore, treatment with FME caused a rapid loss of mitochondrial transmembrane potential, stimulation of generation of reactive oxygen species (ROS), release of mitochondrial cytochrome c into cytosol, and GSH depletion. Anti-oxidants such as N-acetylcysteine, catalase, superoxide dismutase, allopurinol, and pyrrolidine dithiocarbamate, but not diphenylene iodonium, significantly inhibited FME-induced cell death. In addition, the results showed that FME-induced apoptosis was accompanied by up-regulation of Bax and Bad, and down-regulation of Bcl-2 and Bcl-XL. Taken together, induction of apoptosis on HL-60 cells by FME was mainly associated with ROS production, GSH depletion, mitochondrial dysfunction, and caspase activation.
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PMID:Apoptosis-inducing active components from Corbicula fluminea through activation of caspase-2 and production of reactive oxygen species in human leukemia HL-60 cells. 1654 98

Bicyclol, a second generation of synthetic hepatoprotectant being used in China for anti-hepatitis therapy, shows chemosensitizing effect on reverting multiple drug resistance (MDR) of cytostatic agents in two established MDR carcinoma cell lines, vincristine resistant human stomatic epidermoid carcinoma VinRKB and adriamycin resistant human breast carcinoma AdrRMCF-7. The reversal rate of drug resistance was calculated from the changes of the IC50 of cell growth inhibition. Bicyclol at the concentration of 25, 50, 100 microM induced 2.8 7.3 and 20.7 fold, respectively, reversal of vincristine resistance in VinRKB cell. Bicyclol also reversed the cross-resistance of VinRKB cell to taxol and AdrRMCF-7 cell resistance to adriamycin at the similar range of potency. Further, Bicyclol recovered the reduced accumulation of adriamycin in AdrRMCF-7 cell partially to the level in drug-sensitive MCF-7 cell, indicate the inhibition of MDR related membrane efflux pump system. Overexpression of membrane p-glycoprotein coded by Mdr-1 genes, the most common efflux pump correlated to MDR, was found in both VinRKB and AdrRMCF-7 cells by Western blot and immunocytochemistry as compared with drug-sensitive cells. The p-glycoprotein was decreased to the levels in drug-sensitive cells when VinRKB and AdrRMCF-7 cells were treated with Bicyclol for 12-72 hours. Both VinRKB and AdrRMCF-7 cells showed increased GSH contents, and AdrRMCF-7 cell showed increased GST activity and the overexpression of Bcl-2 protein, by which molecules are tightly related to the MDR formation besides Mdr-1 p-glycoprotein. Bicyclol reduced the GSH contents, GST activities and Bcl-2 expression. All these data demonstrate that, by modifying the expressions of Mdr-1, GSH/GST and Bcl-2, Bicyclol increases the intracellular drug concentration and sensitizes the resistant cells to the anti-carcinoma agents.
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PMID:Chemosensitizing multiple drug resistance of human carcinoma by Bicyclol involves attenuated p-glycoprotein, GST-P and Bcl-2. 1662 75

Gastric cancer and colon cancer are major causes of mortality and morbidity worldwide. Many cancers manifest due to changes in gene expression, particularly those involved in cellular proliferation and apoptosis. Apoptosis is an important process that removes damaged or deleterious cells and contributes to normal cellular and tissue homeostasis. Apoptosis is a tightly regulated process mediated by caspases, and the involvement of the Bcl-2 superfamily of membrane bound proteins, among others. Thus, the therapeutic induction of apoptosis has been proposed as a novel method to eliminate cancer cells. The oxidative pentose pathway (OPP) and the glutathione (GSH) antioxidant defense system play an important role in the regulation of cell growth and apoptosis. The OPP regulates intracellular redox status and provides NADPH for the synthesis of GSH, an important antioxidant. GSH is required to inactivate intracellular reactive oxygen species (ROS) which induce apoptosis and cell injury. Depletion of GSH increases the sensitivity of cells to ROS. Many chemotherapeutic agents induce apoptosis through ROS-mediated cell damage. Therefore, we speculate that the therapeutic inhibition of the OPP and/or the GSH defense system may increase the sensitivity of gastric and colon cancer cells to anti-cancer therapy. Moreover, we hypothesize that the short-chain fatty acid, butyrate, will induce apoptosis in gastric cancer cells and, secondly, that differences in butyrate metabolism will exist between these cancer cell lines.
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PMID:Nutrient and antioxidant modulation of apoptosis in gastric and colon cancer cells. 1676 Jun 45

Piperine, a main component of Piper longum Linn. and Piper nigrum Linn., is a plant alkaloid with a long history of medicinal use in Indian medicine. It is known to exhibit a variety of biological activities which include anti-pyretic, anti-inflammatory, anti-depressant, hepatoprotective and antitumor. Its immunomodulatory role has so far been limited to humoral response. The influence of piperine on murine thymocytes, immunocompromised by cadmium has been reported by us in this investigation. The various biochemical parameters such as oxidative stress markers (ROS and GSH), Bcl-2 protein expression, mitochondrial membrane potential, caspase-3 activity, DNA damage, blastogenesis and T lymphocyte phenotypes were determined. Cadmium (25 microM) induced apoptosis earliest at 6 h. Alterations in ROS and GSH preceded mitochondrial membrane depolarization and caspase-3 activation followed by apoptosis. The phenotypic changes occurred at 18 h and blastogenesis at 72 h. Various conc. of piperine (1, 10 and 50 microg/ml) when added along with Cd (25 microM) from 1.5 to 72 h, caused a dose and time dependent amelioration in all the cellular events mentioned above. Modulation of oxidative stress has earlier been reported to reduce Cd induced apoptosis in murine lymphocytes. Inhibition of the ROS production and replenishment of GSH by piperine, may in part be responsible for the suppression of downstream cascade of events, i.e. apoptosis, blastogenesis and T lymphocyte phenotyping. The study clearly demonstrated the anti-oxidative, anti-apoptotic, and restorative ability against cell proliferative mitogenic response and phenotypic alterations by piperine, suggesting its therapeutic usefulness in immunocompromised conditions.
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PMID:Modulation of cadmium induced alterations in murine thymocytes by piperine: oxidative stress, apoptosis, phenotyping and blastogenesis. 1678 Aug 5

The risk for cardiovascular disease is significantly high in diabetes mellitus. Oxidative stress plays a dominant role in the pathogenesis of diabetes mellitus. Bcl-2 gene has a close connection with antagonizing oxidative stress destroy in many diseases including diabetes. Carvedilol, an adrenoceptor blocker, also has antioxidant and free radical scavenger properties. To study the effect of carvedilol on the antioxidant status and expression of Bcl-2 in healthy and diabetic hearts, we investigated carvedilol-administrated healthy and streptozotocin-induced diabetic rats. After small and large dosage (1 or 10mg/kg/d) carvedilol-administrated for 5 weeks, hemodynamic parameters, the levels of malondialdehyde (MDA), the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and expression of Bcl-2 mRNA in the cardiac tissues of all six groups were measured. Diabetic rats had higher left ventricular end diastolic pressure (LVEDP), lower maximal rate of rise/fall left ventricle pressure development and decline (+/-dP/dtmax). These parameters were improved by administration of carvedilol. Diabetic rats showed elevated MDA level and CAT activity, but lower activities of SOD and GSH-Px. Carvedilol treatment increased activities of antioxidant enzymes and expression of Bcl-2 in healthy rats as well as diabetic rats. These results indicate that carvedilol improves cardiac function via its antioxidant property in diabetic rats partly.
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PMID:Carvedilol improved diabetic rat cardiac function depending on antioxidant ability. 1678 Sep 94


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