Summary: 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 ra...Summary: 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 immunohistichemistry 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.展开更多
目的:构建抗HER2重组融合蛋白基因ScFv/tBid,并探讨其对骨肉瘤E10细胞的促调亡作用。方法:通过间接免疫荧光染色、流式细胞仪(FCM)检测E10细胞膜表面HER2的表达。将抗HER2单链抗体基因e23sFv与铜绿假单胞菌外毒素PE的转膜结构域基因(PE...目的:构建抗HER2重组融合蛋白基因ScFv/tBid,并探讨其对骨肉瘤E10细胞的促调亡作用。方法:通过间接免疫荧光染色、流式细胞仪(FCM)检测E10细胞膜表面HER2的表达。将抗HER2单链抗体基因e23sFv与铜绿假单胞菌外毒素PE的转膜结构域基因(PEⅡ)和tBid基因连接,构建抗HER2重组融合蛋白基因ScFv/tBid,将其克隆入真核表达载体pCMV中构建重组pCMV-ScFv/tBid载体,转染骨肉瘤E10细胞。间接免疫荧光法检测目的蛋白表达和细胞形态学变化,Annexin V染色流式细胞术及TUNEL法检测E10细胞的凋亡情况。结果:流式细胞仪检测到E10细胞膜表面有HER2的表达。成功构建重组融合蛋白基因质粒pCMV-ScFv/tBid。重组质粒转染E10细胞后,间接免疫荧光双标记染色检测到E10细胞中tBid的过表达;细胞色素C在细胞质中出现;细胞出现明显的固缩、核浓缩等形态特征。Annexin V染色后流式细胞仪检测可见实验组细胞凋亡率较对照组明显升高(16.1% vs 4.5%);TUNEL染色显示,E10细胞出现典型的凋亡特征。结论:重组抗HER2融合蛋白基因ScFv/tBid可以在转染的骨肉瘤E10细胞中表达,并诱导骨肉瘤细胞发生凋亡。展开更多
AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture,...AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.展开更多
AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (D...AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells.展开更多
BACKGROUND:Harmine has antitumor and antinociceptive effects,and inhibits human DNA topoisomerase.However no detailed data are available on the mechanisms of action of harmine in hepatocellular carcinoma.This study ai...BACKGROUND:Harmine has antitumor and antinociceptive effects,and inhibits human DNA topoisomerase.However no detailed data are available on the mechanisms of action of harmine in hepatocellular carcinoma.This study aimed to investigate the effects of harmine on proliferation and apoptosis and the underlying mechanisms in the human hepatocellular carcinoma cell line HepG2.METHODS:The proliferation of HepG2 cells was determined by the cell counting kit-8 (CCK-8) assay and the clone formation test.The morphology of HepG2 cells was examined using fluorescence microscopy after Hoechst 33258 staining Annexin V/propidium iodide (PI) was used to analyze apoptosis and PI to analyze the cell cycle.Western blotting was used to assess expression of the apoptosis-regulated genes Bcl-2,Bax,Bcl-xl,Mcl-1,caspase-3,and caspase-9 Mitochondrial transmembrane potential (Ψ m) was determined using JC-1.RESULTS:Harmine inhibited the proliferation of HepG2 cells in a dose-dependent manner.Hoechst 33258 staining revealed nuclear fragmentation and chromosomal condensation,cell shrinkage,and attachment loss in HepG2 cells treated with harmine.The percentage of the sub/G1 fraction was increased in a concentration-dependent manner,indicating apoptotic cell death.PI staining showed that harmine changed the cell cycle distribution,by decreasing the proportion of cells inG0/G1 and increasing the proportion in S and G2/M.Harmine induced apoptosis in a concentration-dependent manner,with rates of 20.0%,32.7% and 64.9%,respectively.JC-1 revealed a decrease in Ψ m.Apoptosis of HepG2 cells was associated with caspase-3 and caspase-9 activation,down-regulation of Bcl-2,Mcl-1,and Bcl-xl,and no change in Bax.CONCLUSIONS:Harmine had an anti-proliferative effect in HepG2 cells by inducing apoptosis.Mitochondrial signal pathways were involved in the apoptosis.The cancer-specific selectivity shown in this study suggested that harmine is a promising novel drug for human hepatocellular carcinoma.展开更多
Summary：To investigate the effects of ATRA, acitretin and tazarotene on the growth and apoptosis of human tongue squamous cell carcinoma cell line Tca8113. The effect of retinoids on growth of Tca8113 cells in vitro ...Summary：To investigate the effects of ATRA, acitretin and tazarotene on the growth and apoptosis of human tongue squamous cell carcinoma cell line Tca8113. The effect of retinoids on growth of Tca8113 cells in vitro was examined by MTT assay and Trypan blue exclusion assay. Cell cycle analysis, early apoptosis analysis with double staining with Annexin V-FITC and PI, and active caspase-3 analysis with the staining of FITC-conjugated monoclonal rabbit anli-active caspase-3 antibody were made by flow cytometer. Streptavidin-biotin complex （SABC） immunocytochemical assays were employed for the detections of Bax/Bcl-2 proteins expressions. Our results showed that the retinoids inhibited growth of Tca8113 cells in a dose-and time-dependent manner with maximal inhibition 24 h after treatment of 10 5 mol/L. 10^-5 mol/L retinoids altered cell cycle distribution of Tca8113 cells, revealing an increase in G0/G1-phase population, a decrease in S-phase population and the inhibition of G1/S switching. 10^-5 mol/L retinoids significantly induced apoptosis of Tca8113 cells （all P〈0.05）, elevated the cells population with detectable active caspase-3 （P〈 0.05 for all）, increased the number of cells forming Bax and decreased the number of cells forming Bcl-2 significantly （all P〈0.05）. Acitretin played a most prominent role among the retinoids. It is concluded that the inhibition of cell cycle progress of Tca8113 cells by ATRA, acitretin and tazarotene is one of the possible mechanisms for proliferation arrest of TcaS113 cells elicited by the retinoids. The retinoids mediate apoptosis in TcaS113 cells that may be caspase-dependent through mitochondria pathway. High concentration retinoids inhibit growth of Tca8113 cells in vitro by interfering with proliferation and inducing apoptosis of cells. Acitretin may be an alternative medicine for the prevention and treatment of tongue squamous cell carcinoma.展开更多
文摘Summary: 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 immunohistichemistry 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.
文摘目的:构建抗HER2重组融合蛋白基因ScFv/tBid,并探讨其对骨肉瘤E10细胞的促调亡作用。方法:通过间接免疫荧光染色、流式细胞仪(FCM)检测E10细胞膜表面HER2的表达。将抗HER2单链抗体基因e23sFv与铜绿假单胞菌外毒素PE的转膜结构域基因(PEⅡ)和tBid基因连接,构建抗HER2重组融合蛋白基因ScFv/tBid,将其克隆入真核表达载体pCMV中构建重组pCMV-ScFv/tBid载体,转染骨肉瘤E10细胞。间接免疫荧光法检测目的蛋白表达和细胞形态学变化,Annexin V染色流式细胞术及TUNEL法检测E10细胞的凋亡情况。结果:流式细胞仪检测到E10细胞膜表面有HER2的表达。成功构建重组融合蛋白基因质粒pCMV-ScFv/tBid。重组质粒转染E10细胞后,间接免疫荧光双标记染色检测到E10细胞中tBid的过表达;细胞色素C在细胞质中出现;细胞出现明显的固缩、核浓缩等形态特征。Annexin V染色后流式细胞仪检测可见实验组细胞凋亡率较对照组明显升高(16.1% vs 4.5%);TUNEL染色显示,E10细胞出现典型的凋亡特征。结论:重组抗HER2融合蛋白基因ScFv/tBid可以在转染的骨肉瘤E10细胞中表达,并诱导骨肉瘤细胞发生凋亡。
基金National Natural Science Foundation of China,No.39770300,30070873the Overseas Chinese Affairs Office of the State Council Foundation,No.98-33
文摘AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.
基金National Natural Science Foundation of China,No.39770300,30070873the Overseas Chinese Affairs Office of the State Council Foundation,No.98-33
文摘AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells.
基金supported by grants from the Sci-Tech Project Foundation of Guangdong Province,China (2010B031600248)the National Natural Science Foundation of China (30772131)
文摘BACKGROUND:Harmine has antitumor and antinociceptive effects,and inhibits human DNA topoisomerase.However no detailed data are available on the mechanisms of action of harmine in hepatocellular carcinoma.This study aimed to investigate the effects of harmine on proliferation and apoptosis and the underlying mechanisms in the human hepatocellular carcinoma cell line HepG2.METHODS:The proliferation of HepG2 cells was determined by the cell counting kit-8 (CCK-8) assay and the clone formation test.The morphology of HepG2 cells was examined using fluorescence microscopy after Hoechst 33258 staining Annexin V/propidium iodide (PI) was used to analyze apoptosis and PI to analyze the cell cycle.Western blotting was used to assess expression of the apoptosis-regulated genes Bcl-2,Bax,Bcl-xl,Mcl-1,caspase-3,and caspase-9 Mitochondrial transmembrane potential (Ψ m) was determined using JC-1.RESULTS:Harmine inhibited the proliferation of HepG2 cells in a dose-dependent manner.Hoechst 33258 staining revealed nuclear fragmentation and chromosomal condensation,cell shrinkage,and attachment loss in HepG2 cells treated with harmine.The percentage of the sub/G1 fraction was increased in a concentration-dependent manner,indicating apoptotic cell death.PI staining showed that harmine changed the cell cycle distribution,by decreasing the proportion of cells inG0/G1 and increasing the proportion in S and G2/M.Harmine induced apoptosis in a concentration-dependent manner,with rates of 20.0%,32.7% and 64.9%,respectively.JC-1 revealed a decrease in Ψ m.Apoptosis of HepG2 cells was associated with caspase-3 and caspase-9 activation,down-regulation of Bcl-2,Mcl-1,and Bcl-xl,and no change in Bax.CONCLUSIONS:Harmine had an anti-proliferative effect in HepG2 cells by inducing apoptosis.Mitochondrial signal pathways were involved in the apoptosis.The cancer-specific selectivity shown in this study suggested that harmine is a promising novel drug for human hepatocellular carcinoma.
文摘Summary：To investigate the effects of ATRA, acitretin and tazarotene on the growth and apoptosis of human tongue squamous cell carcinoma cell line Tca8113. The effect of retinoids on growth of Tca8113 cells in vitro was examined by MTT assay and Trypan blue exclusion assay. Cell cycle analysis, early apoptosis analysis with double staining with Annexin V-FITC and PI, and active caspase-3 analysis with the staining of FITC-conjugated monoclonal rabbit anli-active caspase-3 antibody were made by flow cytometer. Streptavidin-biotin complex （SABC） immunocytochemical assays were employed for the detections of Bax/Bcl-2 proteins expressions. Our results showed that the retinoids inhibited growth of Tca8113 cells in a dose-and time-dependent manner with maximal inhibition 24 h after treatment of 10 5 mol/L. 10^-5 mol/L retinoids altered cell cycle distribution of Tca8113 cells, revealing an increase in G0/G1-phase population, a decrease in S-phase population and the inhibition of G1/S switching. 10^-5 mol/L retinoids significantly induced apoptosis of Tca8113 cells （all P〈0.05）, elevated the cells population with detectable active caspase-3 （P〈 0.05 for all）, increased the number of cells forming Bax and decreased the number of cells forming Bcl-2 significantly （all P〈0.05）. Acitretin played a most prominent role among the retinoids. It is concluded that the inhibition of cell cycle progress of Tca8113 cells by ATRA, acitretin and tazarotene is one of the possible mechanisms for proliferation arrest of TcaS113 cells elicited by the retinoids. The retinoids mediate apoptosis in TcaS113 cells that may be caspase-dependent through mitochondria pathway. High concentration retinoids inhibit growth of Tca8113 cells in vitro by interfering with proliferation and inducing apoptosis of cells. Acitretin may be an alternative medicine for the prevention and treatment of tongue squamous cell carcinoma.
文摘目的探讨黄酮类化合物芹菜素对大鼠实验性心肌缺血/再灌注(ischemia/reperfusion,I/R)时心肌细胞凋亡与Bcl-2、Bax、Caspase-3蛋白表达的影响,并分析心肌组织病理学损伤程度。方法采用结扎左冠状动脉前降支,心肌缺血45 min,再灌注2 h制作缺血/再灌注模型。将大鼠随机分为8组,即正常组(normal group,Normal)、假手术组(sham oper-ation group,Sham)、生理盐水缺血/再灌注组(saline ischemi-a-reperfusion group,NS)、溶剂对照组(solvent control group,Sol)、美托洛尔对照组(metoprolol control group,Meto)、芹菜素低、中、高剂量(1、2、4 mg.kg-1)用药组(apigenin low,medium and high dose treatment group,Api1,Api2,Api4)。再灌注2 h后迅速取出心脏,TUNEL法原位标记凋亡的心肌细胞;免疫组化法测Bcl-2、Bax和Caspase-3蛋白表达;做病理组织切片检查心肌损伤情况。结果芹菜素各剂量组心肌细胞凋亡率明显低于NS组(P<0.05),Api1,Api2,Api4能剂量依赖性地降低大鼠缺血/再灌注心肌细胞凋亡率;芹菜素各剂量组剂量依赖性地提高大鼠心肌缺血/再灌注的Bcl-2蛋白表达量(P<0.05)、降低大鼠心肌缺血/再灌注的Bax、Caspase-3蛋白表达量(P<0.05);芹菜素各剂量组与NS组比较,心肌组织损伤的病理学变化明显减轻(P<0.05)。结论芹菜素对缺血/再灌注心肌的保护效应可能与其抑制缺血/再灌注心肌细胞凋亡有关;芹菜素抗心肌凋亡作用的机制可能与其上调Bcl-2蛋白表达和下调Bax、Caspase-3蛋白表达有关;芹菜素能明显减轻心肌组织损伤。
