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)

Methional is a potent inducer of apoptosis in an interleukin 3-dependent murine lymphoid cell line BAF3 b0 when it is added to the culture medium. In these cells transfected with the bcl2 gene, BAF3 bcl2, the apoptotic-inducing activity of methional is dramatically reduced. The addition of disulfiram (an inhibitor of aldehyde dehydrogenase) in order to reduce methional oxidation brought about an increase in apoptosis in BAF3 b0 but not in BAF3 bcl2 cells. In contrast, the addition of quercetin (an inhibitor of aldehyde reductase) in an attempt to diminish methional reduction increased apoptosis in both BAF3 b0 and BAF3 bcl2 cells. The extent of DNA fragmentation in BAF3 bcl2 cells approached that in BAF3 b0 cells in the presence of quercetin and exogenous methional, suggesting a defect in methional biosynthesis in BAF3 bcl2 cells. Direct evidence for this was obtained by measuring labelled methional in cells incubated with the sodium, salt of [U-14C]4-methylthio-2-oxobutanoic acid (MTOB), the precursor of methional. The 80% decrease in labelled methional in BAF3 bcl2 compared with BAF3 b0 cells was accompanied by a concomitant rise in the transamination of [14C]MTOB to [14C]methionine in BAF3 bcl2 cells. Inhibition of the transaminase, however, by a synthetic transition-state-type compound, pyridoxal-L-methionine ethyl ester, induced apoptosis in BAF3 b0 but not in BAF3 bcl2 cells, confirming that the defect in BAF3 bcl2 cells was not in the transaminase itself but rather in the oxidative decarboxylation step MTOB --> methional. In addition, no evidence was obtained for the synthesis of [14C]malondialdehyde from [14C]methional in BAF3 bcl2 cells. As these cells show no deficiency in their content of reactive oxygen species compared with that of BAF3 b0 cells, they may possess some other defect in the beta-hydroxylase enzyme system itself.
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PMID:Altered methional homoeostasis is associated with decreased apoptosis in BAF3 bcl2 murine lymphoid cells. 861 Nov 83

Apoptosis in human placental villi is reported to increase until close to delivery. However, the involvement of the apoptotic process in the initiation of labor, and more particularly in relation to the decrease in placental perfusion during uterine contractions, remains unknown. The purpose of the study was to examine the reactivity of the apoptotic machinery in term placentae obtained before or after the onset of labor and after in vitro incubations. The incidence of apoptotic nuclei (< 1%) as evidenced by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method, and the histological distribution of immunoreactive Bcl-2, Bax, and Bcl-x proteins, were similar in placentae collected after delivery and before the onset of labor and in placental explants maintained overnight at 4 degrees C in a minimal salt-Hepes medium. By contrast, 28% of nuclei contained fragmented DNA when placental explants were incubated overnight at 37 degrees C. This marked increase was associated with a decrease in the intensity of the Bcl-2 immunostaining and an increase in the intensity of Bax and Bcl-x immunostaining. In conclusion, the present study clearly evidences the presence of an active apoptotic machinery in term placental cells that is not involved in normal parturition.
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PMID:Apoptosis in human term placenta is not increased during labor but can be massively induced in vitro. 1041 27

The antileukemic activity of cytotoxic drugs is increasingly thought to be the result of induction of apoptosis. Several proto-oncogenes have been related to the regulation of this process. In this study we evaluated the relation between bcl-2 expression, spontaneous and dexamethasone (DXM) induced apoptosis, and in vitro resistance to DXM, prednisolone (PRD) and cytarabine (ARA) determined using the total cell kill colorimetric methyl-thiazol-tetrazolium salt (MTT) assay, in childhood acute lymphoblastic leukemia (ALL). Drug resistance was expressed as the LC50 value, the drug concentration lethal to 50% of the cells. Fourty-six samples taken at initial diagnosis (iALL) and 31 samples taken at relapse (rALL) were incubated in culture medium, with and without DXM. Bcl-2 expression and apoptosis were measured flowcytometrically, the latter using DNA histogram analysis. Bcl-2 expression was 1.4 fold higher in rALL than in iALL (p = 0.008). Both spontaneous and DXM induced apoptosis increased significantly from 0 to 48 hours (in up to 71%, 81% of the cells respectively). Bcl-2 expression was inversely correlated with the extent of spontaneous apoptosis after 24 hours in iALL (r = -0.40, p = 0.05). Relapsed samples, but not samples obtained at presentation, expressing high levels of bcl-2 displayed increased resistance to drug induced apoptosis (r = -0.63, p = 0.02). In iALL high bcl-2 expression appeared to be related to low LC50 values of ARA. No correlations were found for DXM or PRD. In conclusion, DXM excerts its cytotoxic effect at least partly by means of induction of apoptosis. Bcl-2 inhibits drug induced apoptosis in rALL. However in iALL bcl-2 expression is not associated with increased in vitro drug resistance, nor with increased resistance to drug induced apoptosis.
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PMID:BCL-2 expression in childhood leukemia versus spontaneous apoptosis, drug induced apoptosis, and in vitro drug resistance. 1050 Aug 8

Dimethylammonium salt of 2,4-dichlorophenoxyacetic acid (DMA-2,4-D) is a widely used herbicide that is considered moderately toxic. In the present study we found that DMA-2,4-D is able to cause apoptosis in peripheral blood lymphocytes of healthy individuals and Jurkat T cells. Apoptosis induced by DMA-2,4-D was dose and time dependent, independent of Fas, TNF receptor 1 or the aromatic hydrocarbon receptor, and involved disruption of the mitochondrial transmembrane potential and activation of caspase-9. ZVAD-FMK, a broad-spectrum inhibitor of caspases, blocked DMA-2,4-D-induced apoptosis completely. While an inhibitor of caspase-9, as well as caspase-9 and caspase-3 inhibitors in combination, strongly blocked DMA-2,4-D-induced apoptosis, an inhibitor of caspase-3 had a moderate inhibitory effect. Unlike Fas-mediated apoptosis, the initiator caspase, caspase-8, was not involved in DMA-2,4-D-induced apoptosis. Transfection of Jurkat cells with Bcl-2 prevented DMA-2,4-D-induced disruption of the mitochondrial transmembrane potential and led to a complete blockage of apoptosis. Our data indicate that DMA-2,4-D kills human lymphocytes by initiating apoptosis via a direct effect on mitochondria. The activation of caspases occurs downstream of mitochondrial damage, and the dysfunction of mitochondria appears to be sufficient for triggering all downstream events leading to apoptosis.
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PMID:Induction of apoptosis in human lymphocytes by the herbicide 2,4-dichlorophenoxyacetic acid. 1116 16

The exact mechanisms responsible for the progression of heart failure remain unclear. We investigated the in vivo relationship between the incidence of apoptotic cell death and left ventricular function serially from the beginning of hypertension to decompensated heart failure in Dahl salt-sensitive rats. Dahl salt-resistant and Dahl salt-sensitive rats were fed on a high-salt diet from 6 weeks of age. Systolic blood pressure was recorded by the tail-cuff method every week. Cardiac function in vivo was evaluated by echocardiography and cardiac catheterization. Cardiomyocyte apoptosis was detected by the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) method. The gene expression of Bax, Bcl-2 and Bcl-xL was analysed by Northern blotting. The TUNEL method revealed that the incidence of cardiomyocyte apoptosis was significantly increased in the hearts of 18-week-old Dahl salt-sensitive rats (apoptotic index 1.3 +/- 0.1%). Northern blot analysis revealed that the Bcl-xL mRNA level increased gradually during the progression towards heart failure. In conclusion, these data suggest that cardiomyocyte apoptosis is a terminal event, and plays a role as an aggravating factor in the vicious cycle of heart failure.
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PMID:Relationship between cardiomyocyte cell death and cardiac function during hypertensive cardiac remodelling in Dahl rats. 1186 74

Programmed cell death (PCD) is a fundamental cellular process conserved in metazoans, plants and yeast. Evidence is presented that salt induces PCD in yeast and plants because of an ionic, rather than osmotic, etiology. In yeast, NaCl inhibited growth and caused a time-dependent reduction in viability that was preceded by DNA fragmentation. NaCl also induced the cytological hallmarks of lysigenous-type PCD, including nuclear fragmentation, vacuolation and lysis. The human anti-apoptotic protein Bcl-2 increased salt tolerance of wild-type yeast strain and calcineurin-deficient yeast mutant (cnb1Delta) that is defective for ion homeostasis, but had no effect on the NaCl or sorbitol sensitivity of the osmotic hypersensitive hog1Delta mutant -- results that further link PCD in the response to the ion disequilibrium under salt stress. Bcl-2 suppression of cnb1Delta salt sensitivity was ENA1 (P-type ATPase gene)-dependent, due in part to transcriptional activation. Salt-induced PCD (TUNEL staining and DNA laddering) in primary roots of both Arabidopsis thaliana wild type (Col-1 gl1) and sos1 (salt overly sensitive) mutant seedlings correlated positively with treatment lethality. Wild-type plants survived salt stress levels that were lethal to sos1 plants because secondary roots were produced from the shoot/root transition zone. PCD-mediated elimination of the primary root in response to salt shock appears to be an adaptive mechanism that facilitates the production of roots more able to cope with a saline environment. Both salt-sensitive mutants of yeast (cnb1Delta) and Arabidopsis (sos1) exhibit substantially more profound PCD symptoms, indicating that salt-induced PCD is mediated by ion disequilibrium.
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PMID:Salt causes ion disequilibrium-induced programmed cell death in yeast and plants. 1187 77

Colchicine has been shown to prevent kidney injury in chronic cyclosporine nephrotoxicity; however, the mechanisms of its action are undetermined. The purpose of this study was to clarify whether colchicine prevents cyclosporine-induced kidney injury by decreasing kidney-cell apoptosis. We also sought to determine whether such an antiapoptotic effect was related to Bcl-2/Bax protein and caspase3 activity. Adult male Sprague-Dawley rats kept on a salt-depleted diet (0.05% sodium) were treated daily for 28 days with cyclosporine (15 mg/kg in 1 mL/kg olive-oil vehicle), colchicine (30 microg/kg in 100% ethanol, diluted with sterile saline solution to a final concentration of 30 microg/mL), or both cyclosporine and colchicine. Kidney function, histomorphologic findings, in situ terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate-biotin nick end-labeling assay, expressions of Bcl-2 and Bax proteins, and caspase-3 enzymatic activity were compared for the different treatment groups. Compared with the vehicle-treated rats, rats given cyclosporine showed a decline in creatinine clearance rate, an increase in serum creatinine concentration, tubulointerstitial fibrosis, and an increase in the number of apoptotic cells (all P <.01). Concomitant administration of colchicine significantly reversed all the above parameters (all P <.05). The decreased expression of Bcl-2 and the ratio of Bcl-2 to Bax protein seen in cyclosporine-treated rat kidneys were significantly increased after colchicine treatment, accompanying a suppression of caspase-3 activity (P <.05). Furthermore, the decreased apoptotic cell death was closely correlated with improved renal tubulointerstitial fibrosis (r = 0.583, P <.05). These findings strongly suggest that a renoprotective effect of colchicine on cyclosporine-induced nephrotoxicity is coassociated with a decrease in apoptotic cells.
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PMID:Colchicine decreases apoptotic cell death in chronic cyclosporine nephrotoxicity. 1206 35

Evidence from live cell bioassays shows that the flat mucosa from patients with colon cancer exhibits resistance to bile salt-induced apoptosis. Three independent cell lines derived from the colonic epithelial cell line HCT-116 were selected for resistance to bile salt-induced apoptosis. These cell lines were developed as tissue culture models of apoptosis resistance. Selection was carried out for resistance to apoptosis induced by sodium deoxycholate (NaDOC), the bile salt found in highest concentrations in human fecal water. Cultures of HCT-116 cells were serially passaged in the presence of increasing concentrations of NaDOC. The resulting apoptosis resistant cells were able to grow at concentrations of NaDOC (0.5 mM) that cause apoptosis in a few hours in unselected HCT-116 cells. These cells were then analyzed for changes in gene expression. Observations from cDNA microarray, 2-D gel electrophoresis/MALDI-mass spectroscopy, and confocal microscopy of immunofluorescently stained preparations indicated underexpression or overexpression of numerous genes at either the protein or mRNA level. Genes that may play a role in apoptosis and early stage carcinogenesis have been identified as upregulated in these cell lines, including Grp78, Bcl-2, NF-kappaB(p50), NF-kappaB(p65), thioredoxin peroxidase (peroxiredoxin) 2, peroxiredoxin 4, maspin, guanylate cyclase activating protein-1, PKCzeta, EGFR, Ras family members, PKA, PI(4,5)K, TRAF2 and BIRC1 (IAP protein). Under-expressed mRNAs included BNIP3, caspase-6, caspase-3 and serine protease 11. NF-kappaB was constitutively activated in all three resistant cell lines, and was responsible, in part, for the observed apoptosis resistance, determined using antisense oligonucleotide strategies. Molecular and cellular analyses of these resistant cell lines has suggested potential mechanisms by which apoptosis resistance may develop in the colonic epithelium in response to high concentrations of hydrophobic bile acids that are associated with a Western-style diet. These analyses provide the rationale for the development of hypothesis-driven intermediate biomarkers to assess colon cancer risk on an individual basis.
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PMID:Development and molecular characterization of HCT-116 cell lines resistant to the tumor promoter and multiple stress-inducer, deoxycholate. 1250 30

F 11782 (2",3"-bis-pentafluorophenoxyacetyl-4",6"ethylidene-beta-D-glucoside of 4'-phosphate-4'-dimethylepipodophyllotoxin-2N-methyl glucamine salt), is a novel dual catalytic inhibitor of topoisomerases I and II characterised by marked in vivo antitumour activity, which also proved cytotoxic and exhibited DNA damaging properties in vitro. Mechanisms associated with this cell killing by F 11782 have been examined in P388 leukaemia cells. Treatment with F 11782 resulted in a dose-dependent DNA fragmentation coupled with the characteristic morphological features of apoptosis. Apoptosis-inducing concentrations of F 11782 induced caspases-3/7 activation accompanied by proteolytic cleavage of poly(ADP-ribose)-polymerase, which could be inhibited by the caspase inhibitor acetyl-Asp-Glu-Val-Asp-aldehyde. In addition, F 11782-induced apoptosis in P388 cells was associated with an increased expression of the pro-apototic Bax protein, without significant changes in the level of the anti-apoptotic Bcl-2 protein, and with modification at the mitochondrial membrane function. These results indicate that F 11782 leads to apoptosis through a caspase-3/7 dependent mechanism and suggest that the so-called "mitochondrial pathway" is implicated in F 11782-induced apoptosis in P388 cells.
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PMID:Apoptotic cell death induction by F 11782 a novel dual catalytic inhibitor of topoisomerases I and II. 1262 89

Cardiac hypertrophy from pathological stimuli often proceeds to heart failure, whereas cardiac hypertrophy from physiological stimuli does not. In this study, physiological hypertrophy was created by a daily exercise regimen and pathological hypertrophy was created from a high-salt diet in Dahl salt-sensitive rats. The rats continued on a high-salt diet progressed to heart failure associated with an increased rate of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cardiomyocytes. We analyzed primary cultures of these hearts and found that only cardiomyocytes made hypertrophic by a pathological stimulus show increased sensitivity to apoptosis. Examination of the molecular changes associated with these distinct types of hypertrophy revealed changes in Bcl-2 family members and caspases favoring survival during physiological hypertrophy. However, in pathological hypertrophy, there were more diffuse proapoptotic changes, including changes in Fas, the Bcl-2 protein family, and caspases. Therefore, we speculate that this increased sensitivity to apoptotic stimulation along with proapoptotic changes in the apoptosis program may contribute to the development of heart failure seen in pathological cardiac hypertrophy.
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PMID:Alterations in apoptosis regulatory factors during hypertrophy and heart failure. 1500 40


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