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)

Activating mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels is a critical event of pharmacological preconditioning, which can enhance neuronal ability against various insults. mitoK(ATP) channels are abundant in neurons and can be selectively opened by diazoxide (DZ). The aim of this study was to determine whether DZ could restrain neuronal apoptosis induced by anoxia-reoxygenation and to reveal the effect of DZ preconditioning on the expressions of Bcl-2 and Bax proteins in cultured hippocampal neurons. Cultured for 9~10 d in vitro, the hippocampal neurons of Sprague-Dawley rats were assigned to the following 5 groups randomly: Control, DZ 0 mumol/L, DZ 30 mumol/L, DZ 100 mumol/L, DZ 100 mumol/L+5-hydroxydecanoate (5-HD, a selective mitoK(ATP) channel blocker) 100 mumol/L. Prior to oxygen deprivation, the hippocampal neurons except those in the control group were treated with DZ or DZ+5-HD for 1 h per day and this treatment persisted for 3 d. Thereafter, neurons were subjected to anoxia for 4 h and followed by reoxygenation. At 24 h of reoxygenation the neuronal survival rates were measured by MTT method, while the apoptotic rates were assayed by annexin V-FITC staining. The expressions of Bcl-2 and Bax proteins were detected with immunocytochemistry and evaluated by Western blot. Anoxia-reoxygenation injury reduced the survival rates and increased apoptotic rates significantly. In comparison with those in other groups, the survival rate in DZ 100 mumol/L group was increased by about 15%, whereas the apoptotic rate was decreased by almost 12% simultaneously. 5-HD could abolish the neuroprotection afforded by 100 mumol/L DZ. Bcl-2 and Bax proteins in the control normoxic neurons were both expressed slightly, while anoxia-reoxygenation led to high expression of Bax protein. The administration of 100 mumol/L DZ enhanced the expression of Bcl-2 protein by nearly 60%, whereas Bax protein was reduced by approximately 30%. Lower concentrations of DZ had no detectable effects on the expressions of Bcl-2 and Bax proteins. However, beneficial effects of DZ on the expressions of Bcl-2 and Bax proteins were reversed after the co-treatment with 5-HD. In conclusion, 100 mumol/L DZ prevented cultured hippocampal neurons from apoptosis induced by anoxia-reoxygenation possibly through up-regulating the expression of Bcl-2 protein and down-regulating the expression of Bax protein.
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PMID:Diazoxide preconditioning alleviates apoptosis of hippocampal neurons induced by anoxia-reoxygenation in vitro through up-regulation of Bcl-2/Bax protein ratio. 1690 35

How cells die in the absence of oxygen (anoxia) is not understood. Here we report that cells deficient in Bax and Bak or caspase-9 do not undergo anoxia-induced cell death. However, the caspase-9 null cells do not survive reoxygenation due to the generation of mitochondrial reactive oxygen species. The individual loss of Bim, Bid, Puma, Noxa, Bad, caspase-2, or hypoxia-inducible factor 1beta, which are potential upstream regulators of Bax or Bak, did not prevent anoxia-induced cell death. Anoxia triggered the loss of the Mcl-1 protein upstream of Bax/Bak activation. Cells containing a mitochondrial DNA cytochrome b 4-base-pair deletion ([rho(-)] cells) and cells depleted of their entire mitochondrial DNA ([rho(0)] cells) are oxidative phosphorylation incompetent and displayed loss of the Mcl-1 protein under anoxia. [rho(0)] cells, in contrast to [rho(-)] cells, did not die under anoxia. However, [rho(0)] cells did undergo cell death in the presence of the Bad BH3 peptide, an inhibitor of Bcl-X(L)/Bcl-2 proteins. These results indicate that [rho(0)] cells survive under anoxia despite the loss of Mcl-1 protein due to residual prosurvival activity of the Bcl-X(L)/Bcl-2 proteins. Collectively, these results demonstrate that anoxia-induced cell death requires the loss of Mcl-1 protein and inhibition of the electron transport chain to negate Bcl-X(L)/Bcl-2 proteins.
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PMID:Loss of Mcl-1 protein and inhibition of electron transport chain together induce anoxic cell death. 1714 74

Anoxia, the condition of oxygen deprivation, induces apoptosis via the intrinsic apoptotic pathway. Cells deficient in both Bax and Bak do not undergo cell death during anoxia. However, the underlying mechanism of anoxia induced cell death is not well defined. Here we report our latest findings of two critical events that are required to induce cell death during anoxia. First, a key member of the Bcl-2 family of pro-survival proteins, Mcl-1, undergoes proteasomal-dependent degradation. The loss of Mcl-1 protein is independent of Bax or Bak indicating this is an early event in the apoptotic cascade. Second, cells inhibit the mitochondrial electron transport chain to negate the pro-survival function of Bcl-2/Bcl-X(L). These observations indicate that loss of pro-survival function is necessary for anoxia induced cell death.
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PMID:Role of Bcl-2 family members in anoxia induced cell death. 1737