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

TGF-beta1 is a multifunctional regulatory peptide (25 kDa) inducing growth arrest and apoptosis in many normal and neoplastic cells. In the present study, the involvement of proapoptotic (bax) and antiapoptotic (bcl-2) genes in the molecular mechanism of TGF-beta1-induced apoptosis of L1210 leukemic cells was investigated. Bax transcript was measured using the RT-PCR method with GAPDH as a "housekeeping gene" control, whereas Bcl-2 protein was determined using flow cytometry (FITC-conjugated monoclonal anti-Bcl-2 antibody and FITC-conjugated mouse anti-IgG1 antibody as a negative control). Apoptosis was evaluated using fluorescence microscopy and flow cytometry after cell staining with DAPI and sulforhodamine or propidium iodide and Hoechst 33342. ROS generation was assessed by flow cytometry using the oxidation-sensitive fluorescent marker C-DCDHF-DA. The response of L1210 leukemic cells to TGF-beta1 was two-directional: 1) partial arrest of the cell cycle at G1-S transition, and 2) induction of apoptotic cell death. TGF-beta1 increased the number of leukemic cells with typical morphological features of apoptosis: cell shrinkage, condensation of chromatin, pyknosis and fragmentation of nuclei, followed by secondary necrosis. DNA cleavage led to a decrease of the nuclear DNA content and the appearance of a hypodiploid peak sub-G1 in the DNA histogram. The extraction of low-molecular weight DNA fragments from apoptotic cells showed that TGF-beta1-induced apoptosis concerned first of all the cells from G1 phase. Two phases of intracellular ROS generation in TGF-beta1-treated cultures were observed: the first (rapid, 60 min after TGF-beta1 administration), and the second (slow, occurring between 24 and 48h of experiment, respectively). The increase of apoptotic cell number in TGF-beta1-treated cultures (2% FCS/RPMI 1640) was associated with the decrease of cell number expressing bcl-2, and with a significant drop of Bcl-2 level in the remaining cells after 24 h. The dose-dependent relationship between TGF-beta1 concentration and Bcl-2 level was nonlinear and described by power series regression. The lowest Bcl-2 level was noted at 1 ng/ml of TGF-beta1 concentration. The increase of Bax mRNA:GAPDH mRNA ratio was observed 3h after TGF-beta1 (1 ng/ml) administration to both the maintenance (2% FCS/RPMI) and growth promoting (10% FCS/RPMI) medium. Regardless of TGF-beta1 treatment, the quantity of Bax transcript was dependent on FCS concentration, being higher in the growth promoting medium. The results of this study indicate that bax may function as a primary response gene and together with lowered Bcl-2 level may determine the induction of apoptotic process in L1210 leukemic cells exposed to TGF-beta1.
 ...
PMID:Expression of bcl-2 and bax in TGF-beta 1-induced apoptosis of L1210 leukemic cells. 962 23

This work, using RT PCR, studied expression of mRNAs encoding ion transporters, the Na/H antiporter (NHE1), the beta subunit of the Na,K-ATPase pump (ATP1B1), the NaK2Cl symporter (NKCC1), and some proteins unrelated to ion transport: the serum and glucocorticoid dependent kinase (hSGK), beta-actin, a glycolytic enzyme (GAPDH), and regulators of proliferation and apoptosis (p53, Bcl-2) during activation of human lymphocytes with phytohemagglutinin for 4-24 h. Within 24 hours the mRNA levels of NHE1, beta-actin, Bcl-2, and p53 increased by more than 100%, the mRNA levels of ATP1B1, GAPDH, and hSGK, by about 50%, while the mRNA levels of NKCC1 decreased transiently. These results indicate a differential transcriptional control of NHE1, ATP1B1, and NKCC1 following a proliferative stimulus of human lymphocytes.
 ...
PMID:Differential transcription of ion transporters, NHE1, ATP1B1, NKCC1 in human peripheral blood lymphocytes activated to proliferation. 1127 79

Changes in the levels of mRNAs encoding ion transporters (ATP1B1, NHE1, NKCC1), beta-actin, GAPDH, regulators of proliferation and apoptosis (p53, Bcl-2) and kinase hSGK, involved in cell water regulation, were studied using RT PCR in the peripheral human lymphocytes activated with phytohemagglutinin for 4-24 h. The common, "grouped", effect that was found was an increase in the levels of the studied mRNAs after an 8 h activation, sometimes preceded by a delay or slight decrease at the initial stage of 0-4 h. Apart from the common features, some differences were observed in the time courses and amplitudes of the responses of individual mRNAs. The arrangement of the individual mRNA responses in lymphocytes from different donors could differ significantly, thus indicating differential regulation of the studied mRNAs apart from the "grouped" effect. The data obtained confirmed our suggestion that regulation of ion transport at the level of mRNA could be involved in the changes of ion balance at the late stage of lymphocyte activation.
 ...
PMID:[Cell cycle and formation of active form of oxygen in rodent fibroblasts]. 1153 80

Skeletal muscle atrophy is a common feature in alcoholism that affects up to two-thirds of alcohol misusers, and women appear to be particularly susceptible. There is also some evidence to suggest that malnutrition exacerbates the effects of alcohol on muscle. However, the mechanisms responsible for the myopathy remain elusive, and some studies suggest that acetaldehyde, rather than alcohol, is the principal pathogenic perturbant. Previous reports on rats dosed acutely with ethanol (<24 h) have suggested that increased proto-oncogene expression (i.e., c-myc) may be a causative process, possibly via activating preapoptotic or transcriptional pathways. We hypothesized that 1) increases in c-myc mRNA levels also occur in muscle exposed chronically to alcohol, 2) muscle of female rats is more sensitive than that from male rats, 3) raising acetaldehyde will also increase c-myc, 4) prior starvation will cause further increases in c-myc mRNA expression in response to ethanol, and 5) other genes involved in apoptosis (i.e., p53 and Bcl-2) would also be affected by alcohol. To test this, we measured c-myc mRNA levels in skeletal muscle of rats dosed either chronically (6-7 wk; ethanol as 35% of total dietary energy) or acutely (2.5 h; ethanol as 75 mmol/kg body wt ip) with ethanol. All experiments were carried out in male Wistar rats (approximately 0.1-0.15 kg body wt) except the study that examined gender susceptibility in male and female rats. At the end of the studies, rats were killed, and c-myc, p53, and Bcl-2 mRNA was analyzed in skeletal muscle by RT-PCR with an endogenous internal standard, GAPDH. The results showed that 1) in male rats fed ethanol chronically, there were no increases in c-myc mRNA; 2) increases, however, occurred in c-myc mRNA in muscle from female rats fed ethanol chronically; 3) raising endogenous acetaldehyde with cyanamide increased c-myc mRNA in acute studies; 4) starvation per se increased c-myc mRNA levels and at 1 day potentiated the acute effects of ethanol, indicative of a sensitization response; 5) the only effect seen with p53 mRNA levels was a decrease in muscle of rats starved for 1 day compared with fed rats, and there was no statistically significant effect on Bcl-2 mRNA in any of the experimental conditions. The increases in c-myc may well represent a preapoptotic effect, or even a nonspecific cellular stress response to alcohol and/or acetaldehyde. These data are important in our understanding of a common muscle pathology induced by alcohol.
 ...
PMID:Acute and chronic effects of alcohol exposure on skeletal muscle c-myc, p53, and Bcl-2 mRNA expression. 1287 71

Although the transplantation of alginate-poly-L-lysine-alginate encapsulated islets of Langerhans usually is successful, graft survival is still limited. Molecular analysis by RT-PCR of the encapsulated islets may provide insight into the mechanisms that affect islets during graft failure. However, RT-PCR on encapsulated islets is not possible because the poly-L-lysine of the capsule interferes with both cDNA synthesis and PCR amplification. We applied a method that mechanically removes the microcapsules from the islets after a short trypsin-EDTA treatment (decapsulation), thereby enabling RT-PCR analysis. The results of this study show that the decapsulation procedure does not affect islet vitality and has only minor effects on islet function and morphology. The decapsulation does not affect GAPDH, beta-actin, Bcl-2, or Bax gene expression. This method is an improvement over the time-consuming manual dissection of microcapsules because it allows for the rapid and relatively harmless removal of capsules on a larger scale. Decapsulation offers the possibility of applying RT-PCR, as well as other methods, which cannot be performed on encapsulated islets.
 ...
PMID:Effective removal of alginate-poly-L-lysine microcapsules from pancreatic islets by use of trypsin-EDTA. 1456 13

The effect of prolactin on apoptosis and the expression of bcl-2 and bax in HC11 mouse mammary epithelial cells were investigated. Flow cytometric analysis of Bcl-2 level (FITC-conjugated monoclonal anti-Bcl-2 antibody and FITC-conjugated monoclonal anti-IgG1 antibody as a negative control), number of apoptotic cells and cell cycle phases (DNA stained with DAPI) was performed. Bax transcript was measured using the RT-PCR method with GAPDH serving as a reference gene. Administration of prolactin (5 microg/ml) in the presence of insulin stimulated differentiation of mammary epithelial cells, which manifested in stopping cells at G0/G1 phase, cell swelling and increase of cell number with enhanced protein content. Moreover, prolactin highly significantly reduced the extent of apoptosis of HC11 cells during 48 h of incubation. Nevertheless, the apoptotic cell number rose with increased time length of cell culture, probably due to the resulting high cell density and EGF withdrawal from t he incubation medium. The antiapoptotic effect of prolactin was associated with up-regulation of bcl-2 expression, shown as an increase in cell numbers expressing this protooncogene and elevated Bcl-2 content in these cells. A negative relationship (r=-0.87, p< or =0.001) between the number of apoptotic cells and those expressing bcl-2 was also found. Prolactin administration lowered Bax transcript by 68.8% and 70.7% after 3 and 6h, respectively. In conclusion, the results presented indicate that stimulation of bcl-2 expression with simultaneous suppression of bax may be key events in the mechanism of antiapoptotic action of prolactin in HC11 mammary epithelial cells.
 ...
PMID:Antiapoptotic action of prolactin is associated with up-regulation of Bcl-2 and down-regulation of Bax in HC11 mouse mammary epithelial cells. 1464 94

Epidemiology has revealed that physical activity is an important lifestyle factor that reduces the risk of colon cancer. However, the underlying mechanisms of this protective effect have so far not been defined. The aim of this study was to identify molecular targets of physical activity in rat colon mucosa by employing our voluntary exercise model. Twenty male rats underwent a 12-week exercise program, with 9 additional rats serving as a control group. Running distances, body weights and heart weights as measures of physical adaptations were recorded, and changes in mRNA steady-state levels of marker genes involved in vascularization (VEGF, HIF-1 alpha, ODC-1), apoptosis (Bcl-2, PPAR gamma) and prostaglandin synthesis (COX-2) were determined by qRT-PCR. The four housekeeping genes GAPDH, beta-actin, 18S and ALDA served as reference genes. Recorded running distances showed great inter-individual differences resulting in three different groups of low (L-EX, < 2629 m/night; n=5), moderate (M-EX, 3003 - 7458 m/night; n=10) and high (H-EX, > 8314 m/night; n=5) physical activity. The M-EX and H-EX group revealed significant (p<0.05) adaptive changes with an increase in heart mass per kg body weight and a decrease in mean body weight. Amongst the marker genes studied by mRNA expression analysis only ODC-1 appears to be differentially expressed. Its 1.8-fold increased steady-state mRNA level in the H-EX group suggests that synthesis of polyamines may be increased by physical activity. This new finding could provide a link between extensive physical activity and its protective effects on colon cancer development.
 ...
PMID:Exercise associated genes in rat colon mucosa: upregulation of ornithin decarboxylase-1. 1711 18

This paper describes a method allowing correcting false gene expression measured on highly degraded RNA using real-time quantitative reverse transcription-polymerase chain reaction (RTQ-PCR). RNA was isolated from different models (in vitro cell lines, in vivo models of human and dog) and different tissue types. In vitro RNA degradation and modeling of in vivo degradation were applied on intact and degraded total RNA. Gene expression (eg, Bcl-2, GAPDH, PGK, PSME3, RAB2, BAX) was measured using RTQ-PCR. 18S rRNA proved to be the most constant house-keeping gene. Less than 10-fold degraded RNA can be quantified correctly when using 18S rRNA for normalization purposes. Higher-fold degraded RNA can be quantified correctly up to a precision that is comparable to RTQ-PCR measurements on intact RNA when simulating the RNA-species and tissue-specific degradation kinetic.
 ...
PMID:Correcting false gene expression measurements from degraded RNA using RTQ-PCR. 1747 Nov 57

Imatinib is a targeted selective inhibitor of chimaeric Bcr-Abl tyrosine kinase developed for effective therapy of chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL) patients. Unfortunately, evidence now exists to indicate that a portion of such patients treated with imatinib acquire resistance and subsequently relapse. To understand the heterogeneous basis of imatinib resistance, we have investigated the possible mechanism(s) via which hemin, a key regulator of hematopoiesis that is converted to heme intracellularly, renders CML cells less susceptible to imatinib. Hemin at 30-90 aM protected a substantial proportion (>40%) of human Bcr-Abl(+) CML cells (K-562 and KU-812) from imatinib-induced cell killing by increasing the imatinib IC50 value, reducing DNA damage, and promoting erythroid differentiation. RT-PCR assessment of RNA transcripts encoded by human GAPDH, Ggamma-globin, Bcr-Abl, HO-2, Hpr-6, CEBPa, Bcl-2a, Bcl-2b, and Nrf2 genes revealed that hemin selectively counteracted the repression of antiapoptotic Bcl-2a, Bcl-2b, and Nrf2 genes in imatinib-treated cells. These genes are markedly repressed by imatinib alone in human K-562 CML cells. Hemin, however, had no detectable effect on the expression of the Bcr-Abl gene. Moreover, inhibition of de novo heme biosynthesis by succinyl-acetone enhanced the killing effect of imatinib. These data clearly indicate that: (a) cellular heme resulted from de novo biosynthesis and hemin uptake alters the developmental stage of human Bcr-Abl(+) CML cells and their susceptibility to imatinib; (b) cellular heme counteracts the ability of imatinib to repress Bcl-2 and Nrf2 gene expression; and (c) inhibitors of de novo biosynthesis can be developed and combined with imatinib to enhance its antileukemic activity.
 ...
PMID:Hemin counteracts the repression of Bcl-2 and NrF2 genes and the cell killing induced by imatinib in human Bcr-Abl(+) CML cells. 1980 84

Thioredoxins (Trxs) are a class of small molecular redox proteins that play an important role in scavenging abnormally accumulated reactive oxygen species (ROS). Thioredoxin 2 (Trx2) is one member of this family located in mitochondria. Trx2 protects cells from increased oxidative stress and has anti-apoptosis function. Knockout of Trx2 in mice led to early embryonic lethality. However, the essential role of Trx2 during embryogenesis remains unclear. To further investigate the role of Trx2 during embryonic development, we performed Trx2 knockdown in zebrafish and investigated the regulation role of Trx2 during embryonic development. Our results indicate that Trx2 had a high expression in early zebrafish embryos and its knockdown in zebrafish led to defective liver development mainly due to increased hepatic cell death. The increased ROS and the imbalance of members of the Bcl-2 family were involved in cell death induced by Trx2 suppression in zebrafish. The dysregulation of Bax, puma and Bcl-xl promoted the reduction of mitochondrial trans-membrane potential and the mitochondria membrane permeabilization (MMP), which initiated the mitochondrial apoptosis pathway. Additionally, we found that the increase of relocated GAPDH in mitochondria may be another factor responsible for the mitochondrial catastrophe.
...
PMID:The mitochondrial thioredoxin is required for liver development in zebrafish. 2489 69


1 2 Next >>