Animals ; Bufo bufo ; Caspase 3 ; genetics ; metabolism ; Female ; Immunohistochemistry ; Male ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Proto-Oncogene Proteins c-kit ; genetics ; metabolism ; Spinal Cord ; metabolism ; Spinal Cord Injuries ; metabolism ; bcl-2-Associated X Protein ; genetics ; metabolism

OBJECTIVE: To study the mechanism of apoptosis in laryngeal carcinoma cell induced by Stat3 antisense oligodeoxynucleotide (ASODN). METHOD: The designed Stat3 ASODN was transferred into laryngeal carcinoma Hep-2 cell by lipofection. Expression of Bcl-2, Bax and C-Myc were detected by Western blot and PCR. RESULT: Western blot and PCR results demonstrated that Stat3 ASODN could significantly increased the expression of Bax and decreased the expression of Bcl-2 and C-Myc when the concentration of antisense oligodeoxynucleotide were heightened. CONCLUSION Stat3 ASODN participate in apoptosis by enhancing the expression of Bax and reducing the expression of Bcl-2 and C-Myc.
Apoptosis ; genetics ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Humans ; Oligodeoxyribonucleotides, Antisense ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Proto-Oncogene Proteins c-myc ; metabolism ; STAT3 Transcription Factor ; genetics ; bcl-2-Associated X Protein ; metabolism

The B-cell lymphoma/leukemia-2 (Bcl-2) gene is an important member of the Bcl-2 family, a type of protein that plays an important role in the process of cell apoptosis. Bcl-2 does not change the rate of cell proliferation, but prolongs the life and increases the number of cells by counteracting a series of apoptosis. In the recent years, more and more evidence has shown a close correlation of the Bcl-2 gene with the development and progression of benign prostatic hyperplasia (BPH), a disease whose mechanism is not yet fully understood but is drawing more and more attention towards the role of cell apoptosis.
Animals ; Apoptosis ; Humans ; Male ; Mice ; Prostatic Hyperplasia ; genetics ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; Rats

This study aims to explore the effect and mechanism of Danggui Buxue Decoction(DBD)-containing serum in alleviating the H9c2 cell injury caused by the exposure to intermittent low oxygen. H9c2 cells were assigned into five groups: control(CON) group, intermittent low oxygen(IH) group, intermittent low oxygen plus DBD-containing serum(IH+DBD) group, intermittent low oxygen plus the autophagy enhancer rapamycin(IH+RAPA) group, and intermittent low oxygen plus DBD-containing serum and the autophagy inhibitor 3-methyladenine(IH+DBD+3-MA) group. Monodansylcadaverine(MDC) staining was employed to detect the changes of autophagosomes. Cell counting kit-8(CCK-8) assay was employed to determine the activity of myocardial cells, and lactate dehydrogenase(LDH) and creatine kinase(CK) kits were used to measure the LDH and CK levels in the cell culture, which would reflect the degree of cell damage. TdT-mediated dUTP nick-end labeling(TUNEL) staining was used to detect the apoptosis of myocardial cells, and JC-1 fluorescence probe to detect the changes in mitochondrial membrane potential. Western blot was employed to determine the expression levels of the autophagy-related proteins microtubule-associated proteins light chain 3Ⅱ(LC3Ⅱ), microtubule-associated proteins light chain 3Ⅰ(LC3Ⅰ), P62, Parkin and apoptosis related proteins pro caspase-3, caspase-3, B-cell lymphoma-2(Bcl-2), Bcl-2-associated X(Bax). The results showed that compared with the CON group, the IH group showed decreased fluorescence intensity of MDC staining, decreased LC3Ⅱ/LC3Ⅰ ratio, down-regulated Parkin expression, and up-regulated expression of P62. In addition, the IH group showed decreased cell survival rate, increased content of LDH and CK in the culture medium, increased number of TUNEL positive cells, and decreased pro caspase-3/caspase-3 and Bcl-2/Bax ratios and mitochondrial membrane potential. Compared with the IH group, the IH+DBD and IH+RAPA groups showed increased fluorescence intensity of MDC staining, increased LC3Ⅱ/LC3Ⅰ ratio, up-regulated Parkin expression, and down-regulated P62 expression. In addition, the two groups showed increased cell survival rate, reduced content of LDH and CK in the culture medium, decreased number of TUNEL positive cells, and increased pro caspase-3/caspase-3 and Bcl-2/Bax ratios and mitochondrial membrane potential. The IH+DBD+3-MA and IH groups showed no significant differences in the above indicators. Compared with the IH+DBD group, the IH+DBD+3-MA group showed decreased fluorescence intensity of MDC staining, decreased LC3Ⅱ/LC3Ⅰ ratio, down-regulated Parkin expression, and up-regulated P62 expression. In addition, the group had decreased cell survival rate, increased content of LDH and CK in the culture medium, increased number of TUNEL positive cells, decreased pro caspase-3/caspase-3 and Bcl-2/Bax ratios, and declined mitochon-drial membrane potential. To sum up, DBD could promote the mitophagy, inhibit the apoptosis, and alleviated the injury of H9c2 cells exposed to low oxygen.
Oxygen ; bcl-2-Associated X Protein/metabolism* ; Caspase 3/genetics* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Apoptosis ; Autophagy ; Ubiquitin-Protein Ligases ; Microtubule-Associated Proteins

The Bfl-1 gene, which was isolated from human fetal liver and only recently described, is a member of the Bcl-2 gene family. Reverse transcriptase-polymerase chain reaction was performed on RNA drawn from 30 breast cancer tissues to compare the expression of the Bfl-1 gene with other prognostic factors. The median relative ratio was 3.0 (range, 0.12-26.83) and the Bfl-1 gene expression rate was 36.7% (11/30). There was no statistically significant relationship between the clinicopathologic parameters of patients and the expression value of Bfl-1 gene. The level of Bfl-1 gene expression was higher in more advanced breast cancers than in early cancers. There was no significant relationship between the expression values and currently acknowledged prognostic factors, but a higher expression pattern was noticed in the groups of positive hormone receptors and negative p53 and negative c-erbB2, albeit statistically not significant. It seems that the increased expression of the Bfl-1 gene serves as a contributory factor in breast cancer, in the same way that another group of genes, the Bcl-2 family, contributes to apoptosis.
Adult ; Aged ; Aged, 80 and over ; Breast Neoplasms/genetics ; Breast Neoplasms/metabolism* ; Breast Neoplasms/pathology* ; Female ; Gene Expression Regulation, Neoplastic ; Human ; Middle Aged ; Prognosis ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Proto-Oncogene Proteins c-bcl-2/metabolism

Whether conventional hypothermic CPB induces myocyte apoptosis in dog hearts and modulation of bcl-2, bcl-xl, bax, bad, and caspase-3 pathways in this setting was investigated. Ten healthy adult dogs were randomized into sham-operated and CPB groups. Samples of left ventricle were obtained before, during and 3 h after CPB. In situ TUNEL was used to detect apoptotic myocytes. Immunohistochemistry and flow cytometry were employed for detection of expressions of bcl-2, bcl-xl, bax and bad proteins. Z-DEVD-AMC substrate cleavage and TBARS methods were used to measure the activity of caspase-3 and the content of lipid peroxide in LV myocardium, respectively. After CPB, the number of apoptotic myocytes in CPB group was significantly increased. The results of immunohistochemistry demonstrated that bcl-2, bcl-xl, bax and bad proteins were constitutionally present on the sarcolemma of the LV myocytes. FACS results showed that, after CPB, expressions of bax and bad in CPB group were significantly upregulated, while the expressions of bcl-2 and bcl-xl were not significantly changed in both groups. The activity of caspase-3 and the content of lipid peroxide in LV myocardium in CPB group were also significantly increased after CPB. The present study shows that there exists myocardiocyte apoptosis in dog hearts undergoing conventional hypothermic CPB and the myocyte apoptosis is initiated by ischemia and performed during reperfusion. Moreover, the CPB-induced myocyte apoptosis was associated with upregulation of expressions of bax and bad proteins, activation of caspase-3 and increase of oxidative stress.
Animals ; Apoptosis ; Cardiopulmonary Bypass ; Caspases ; metabolism ; Dogs ; Female ; Hypothermia, Induced ; Lipid Peroxidation ; Male ; Myocytes, Cardiac ; metabolism ; pathology ; Proto-Oncogene Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Random Allocation ; bcl-2-Associated X Protein

OBJECTIVETo investigate the effects of paraquat on microRNA expressions in PCl2 cells, and to explore the regulatory mechanism of bcl-2.

METHODSWe used PC12 cells as a popular in vitro cell model system for characterizing the dopaminergic neuron. After 24 h treatment with different concentrations of PQ (0, 62.5 ümol/L), expression difference of microRNA was detected by microarray and examined by real-time quantitative PCR (RT-PCR). Cell apoptosis was analyzed with flow cytometry (FCM) and the relative levels of miR-34a, miR-Let-7e were measured by RT-RCR following the PCl2 cells treatment with 0, 62.5, 125, 250, 500, 1000 ümol/L PQ. Meanwhile, the protein expression of bcl-2 was evaluated by western blot according to forecasting targets analysis databases.

RESULTSCell viability decreased and cell apoptosis increased with increasing PQ concentrations (from 125 to 1000 ümol/L) in a dose-dependent manner (P < 0.05 or P < 0.01). MiRNA microarray showed that after 62.5 ümol/L PQ treatment, 11 miRNAs were significantly up-regulated while 8 miRNAs were down-regulated compared with control (P < 0.01). We chose miR-34a, miR-Let-7e which appeared most remarkable changes in microarray to examine by RT-PCR. It revealed that the level of miR-34a gradually ascended while miR-Let-7e declined after PQ treatment, which are accordant to the microarray results. The protein expression of bcl-2 treated with PQ significantly decreased compared with control and presented a negative correlation with the expression of miR-34a (P < 0.05 or P < 0.01).

CONCLUSIONThe alteration of miRNAs expression may be involved in the neurotoxicity of PQ. Especially, mir-34a negatively regulated the level of bcl-2, and thus plays a key role in PQ-induced cell apoptosis.

Animals ; Apoptosis ; drug effects ; MicroRNAs ; genetics ; PC12 Cells ; Paraquat ; toxicity ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats

This study was aimed to investigate the effects of SUV39H1 siRNA on proliferation and apoptosis of acute myelogenous leukemia KG-1 cell line. The small interfering RNA (siRNA) targeting SUV39H1 gene was designed and transfected into KG-1 cells by Lipofectamine(TM) 2000. Cell growth affected by SUV39H1 siRNA was determined by MTS method. Cell apoptosis was measured by flow cytometry. The expressions of P15 and anti-apoptosis protein such as BCL-2, procaspase-9, procaspase-3 and C-MYC were detected by Western blot. The results indicated that siRNA targeting SUV39H1 inhibited proliferation of KG-1 cells. Proliferated rates were (76.43 ± 1.98)%, (51.31 ± 1.84)%, (37.31 ± 1.61)%, (18.94 ± 3.22)% respectively after transfection with SUV39H1 siRNA at 30, 60, 120, 240 nmol/L for 48 h, while P15 expression was upregulated. Apoptotic cells significantly increased, apoptotic rates were (40.2 ± 5.1)%, (56.8 ± 4.8)%, (71.6 ± 5.6)% respectively after transfection with siRNA targeting SUV39H1 at 30, 60, 120 nmol/L (P < 0.05). The protein expression of BCL-2, procaspase-9, procaspase-3, C-MYC was downregulated after transfection. It is concluded that the siRNA targeting SUV39H1 inhibits cell growth and induces cell apoptosis of KG-1 cell line, which may be a new therapeutic target in human leukemia.
Apoptosis ; genetics ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Methyltransferases ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Proto-Oncogene Proteins c-myc ; metabolism ; RNA Interference ; RNA, Small Interfering ; genetics ; Repressor Proteins ; genetics

To observe the effect of ginsenoside Re on cardiomyocyte apoptosis and Bcl-2/Bax gene expression after ischemia (30 min) and reperfusion (6 h) in rats and to elucidate the possible mechanisms of ginsenoside Re on inhibition of cardiomyocyte apoptosis, the ischemia/reperfusion heart model was established by ligating the left anterior descending branch of coronary artery in Wistar rats. The apoptotic cardiomyocytes were confirmed by transmission electron microscopy and counted by in situ nick end labeling (TUNEL) method and light microscopy. The mRNA and protein expression of Bcl-2 and Bax genes were studied by in situ hybridization and immunohistochemical staining. Mean optical density (OD) value of the positive fields of mRNA and protein expression was quantitatively examined by image analysis system. The results were as follows: (1) The apoptotic cardiomyocytes were found in ischemic fields in the ischemia/reperfusion group and weren't observed in the sham-operation group by transmission electron microscopy; (2) The numbers of the apoptotic cells were 134.45 +/- 45.61/field in the ischemia/reperfusion group, and 90.66 +/- 19.22/field in the ginsenoside Re-treated group. The differences was significant between two groups (P < 0.01); (3) Gene expression of Bcl-2 and Bax were increased significantly in the ischemia/reperfusion group and ginsenoside Re-treated group when compared with the sham-operation group. There was no significant difference in the gene expression of Bcl-2 between the ginsenoside Re-treated group and ischemia/reperfusion group (P > 0.05), but gene expression of Bax was decreased significantly in the ginsenoside Re-treated group as compared with the ischemia/reperfusion group (P < 0.01). The ratio of Bcl-2/Bax was increased significantly in the ginsenoside Re-treated group when compared with the ischemia/reperfusion group and sham-operation group. These findings suggest that myocardial ischemia-reperfusion can induce cardiomyocyte apoptosis, and ginsenoside Re can significantly inhibit cardiomyocyte apoptosis induced by ischemia-reperfusion in rats. It is concluded that ginsenoside Re inhibits cardiomyocyte apoptosis by inhibiting expression of pro-apoptotic Bax gene and raising the ratio of Bcl-2/Bax.
Animals ; Apoptosis ; drug effects ; Female ; Ginsenosides ; pharmacology ; Male ; Myocardial Reperfusion Injury ; genetics ; pathology ; Myocytes, Cardiac ; metabolism ; pathology ; Panax ; Proto-Oncogene Proteins ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; bcl-2-Associated X Protein

To investigate whether the Bcl-2 gene family is involved in modulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL-60 cell line and primary acute myelogenous leukemic cells, the Bcl-2 family member Mcl-1, Bax and Bak and cell cycle proteins including P27kipl, P21wafl, cyclin D3 and pRbp- were selected and their expression detected by SABC immuno-histochemical stain method. The attitude of sub-G1 peak in DNA histogram was determined by FCM. The TUNEL positive cell percentage was identified by terminal deoxynucleotidyl transferase (TdT)-mediated Biotin dUNP end labeling technique. It was found that when HL-60 cells were treated with 25 mumol/L curcumin for 24 h, the expression level of Mcl-1 was down-regulated, but that of Bax and Bak up-regulated time-dependently. There was significant difference in the expression level of Mcl-1, Bax and Bak between the curcumin-treated groups and control group (P < 0.05-0.01). At the same time, curcumin had no effect on progress of cell cycle in primaty acute myelogenous leukemia at newly diagnosis, but could increase the peak of Sub-G1 (P < 0.05), and down-regulate the expression of Mcl-1 and up-regulate the expression of Bax and Bak with the difference being statistically significant. The expression of P27kipl, P21wafl and pRbp- were elevated and that of cyclin D3 decreased in the presence of curcumin. These findings suggested that the Bcl-2 gene family indeed participated in the regulatory process of apoptosis induced by curcumin in HL-60 cells and AML cells. Curcumin can induce apoptosis of primary acute myelogenous leukemic cells and disturb cell cycle progression of HL-60 cells. The mechanism appeared to be mediated by perturbing G0/G1 phases checkpoints which associated with up-regulation of P27kipl, P21wafl and pRbp- expression, and down-regulation of cyclin D3.
Antineoplastic Agents, Phytogenic/pharmacology ; Apoptosis/*drug effects ; Cell Cycle Proteins/*metabolism ; Curcumin/*pharmacology ; Genes, bcl-2/genetics ; HL-60 Cells ; Leukemia, Myelocytic, Acute/pathology ; Neoplasm Proteins/biosynthesis ; Neoplasm Proteins/genetics ; Proto-Oncogene Proteins/biosynthesis ; Proto-Oncogene Proteins/genetics ; Proto-Oncogene Proteins c-bcl-2/*metabolism ; Tumor Cells, Cultured ; bcl-2-Associated X Protein