冬凌草甲素通过激活caspase诱导HeLa细胞凋亡

目的　研究冬凌草甲素诱导人子宫颈癌HeLa细胞凋亡的作用机制。方法　采用形态学观察、DNA凝胶电泳及LDH法。结果　冬凌草甲素能显著诱导HeLa细胞发生凋亡 ,其作用呈明显的量效关系和时间依赖性。形态学观察可见凋亡小体的形成 ,琼脂糖凝胶电泳可见凋亡典型的DNA梯带 ;caspase家族抑制剂 ,caspase 1和 3抑制剂能抑制冬凌草甲素诱导HeLa细胞的凋亡 ,6 8 7μmol·L-1冬凌草甲素作用HeLa细胞 12h使caspase 3的活力提高 2倍。 结论　适宜浓度以下 ,冬凌草甲素 (6 8 7μmol·L-1)诱导HeLa细胞凋亡具有浓度与时间依赖性 ,大剂量 (137 4 μmol·L-1)时 ,冬凌草甲素诱导HeLa细胞坏死的程度强于凋亡 ,且通过激活caspase途径诱导HeLa细胞凋亡。     

紫草素诱导A375-S2细胞凋亡的分子机制研究

目的　研究紫草素诱导人黑色素瘤A375 S2细胞凋亡的分子机制。方法　MTT法、Hoechst33258荧光染色、DNA片段化分析、Westernblot、流式细胞分析以及caspase活力分析等。结果　10μmol·L-1紫草素可明显地抑制A375 S2细胞的生长,其半数有效抑制浓度IC50为 (10 9±1 8)μmol·L-1。10μmol·L-1紫草素可诱导A375 S2细胞凋亡,并经历了caspase 9和caspase 3的激活。紫草素促进p53蛋白的积聚,Bax蛋白表达的上调和Bcl xL蛋白表达的下调,进而导致细胞色素C的释放,致使细胞凋亡。紫草素可使细胞周期停止在G1 期。结论　紫草素可诱导A375 S2细胞周期停止在G1 期,其诱导细胞凋亡的途径经过p53介导的Bax和caspase 9的激活。     

血竭素高氯酸盐诱导人宫颈癌HeLa细胞凋亡的机制

目的研究血竭素高氯酸盐诱导HeLa细胞凋亡机制。方法MTT法测定血竭素高氯酸盐对HeLa细胞的细胞毒作用。通过显微镜，荧光染色观察细胞形态学变化，用琼脂糖凝胶电泳检测DNA片断化。用Western印迹法分析药物对蛋白质表达的影响。结果血竭素高氯酸盐明显抑制HeLa等细胞的增殖，诱导HeLa细胞调亡。Caspase-1，-3，-8，-9及家族抑制剂可明显抑制血竭素高氯酸盐诱导的凋亡。Western印迹结果显示血竭素高氯酸盐作用12 h后Bax及Bcl-X_L的表达明显改变，caspase-3，-8前体及caspase-3底物ICAD和PARP发生降解。结论血竭素高氯酸盐(60 μmol·L^-1)通过改变Bax/Bcl-X_L的表达激活caspase途径诱导HeLa细胞凋亡。     

厚朴酚通过改变Bax/Bcl-X_L表达和激活caspase诱导人宫颈癌HeLa细胞凋亡

目的研究厚朴酚诱导HeLa细胞凋亡机制。方法MTT法测定厚朴酚对HeLa和人正常胚肺HEL299细胞的细胞毒作用。通过显微镜,荧光染色观察细胞形态学变化,用琼脂糖凝胶电泳检测DNA片断化。用Western印迹法分析药物对蛋白质表达的影响。结果厚朴酚明显抑制HeLa细胞的增殖,诱导HeLa细胞调亡。对HEL299细胞的细胞毒作用弱于HeLa细胞。Caspase3,8,9,10及家族抑制剂可明显抑制厚朴酚诱导的凋亡。激动型Fas抗体CH11对厚朴酚诱导的HeLa细胞死亡有协同作用。Western印迹结果显示厚朴酚作用12h后Bax/BclXL表达比率升高,caspase3前体及其底物ICAD和PARP发生降解,磷酸化p53和p53蛋白表达增加。结论厚朴酚(80μmol·L-1)通过改变Bax/BclXL的表达激活caspase途径诱导HeLa细胞凋亡。     

一氧化氮诱导PC12细胞凋亡及人参皂苷Rg1的保护作用

目的　探讨一氧化氮诱导PC12细胞凋亡及人参皂苷Rg1保护作用的可能机制。 方法　DNA凝胶电泳观察DNA的断裂情况 ,流式细胞仪检测线粒体跨膜电位 ,West ernblotting检测胞浆细胞色素C和活化型半胱氨酸蛋白水解酶caspase 3P2 0 水平。结果　一氧化氮供体SNAP(5 0 0μmol·L-1)可诱导PC12细胞凋亡 ,细胞线粒体跨膜电位明显下降、胞浆细胞色素C水平增加及caspase 3得到激活 ;预先经过 5 0、10和 2 0 μmol·L-1等浓度人参皂苷Rg1处理后 ,SNAP诱导的PC12细胞凋亡明显减少 ,同时明显减弱SNAP对细胞线粒体跨膜电位、胞浆细胞色素C水平及cas pase 3激活的影响。 结论　人参皂苷Rg1可抑制一氧化氮诱导PC12细胞凋亡 ,其作用机制可能与其稳定细胞线粒体跨膜电位、减少线粒体细胞色素C向胞浆释放及抑制cas pase 3的激活有关     

氧化还原调控在紫檀芪诱导HeLa细胞内质网凋亡途径中的作用

目的探讨细胞氧化还原调控在紫檀芪引起HeLa细胞凋亡过程中对内质网途径的作用。方法 SRB法评价紫檀芪对HeLa细胞的细胞毒活性。采用细胞形态学和生物化学方法检测细胞凋亡。通过荧光法对细胞内活性氧/GSH的变化进行分析。通过氧化还原相关抑制剂分析凋亡过程中的决定因素。通过半定量RT-PCR表达分析来确定内质网胁迫在紫檀芪诱导HeLa细胞凋亡中的作用。结果紫檀芪对HeLa细胞的IC50为80μmol·L-1。凋亡是紫檀芪对He-La细胞毒活性的主要表现。随着紫檀芪浓度由5μmol·L-1增加至160μmol·L-1,HeLa细胞氧化还原平衡发生明显变化。紫檀芪在80μmol·L-1～120μmol·L-1可引起内质网胁迫分子表达。抑制细胞内过氧化氢的产生会减轻紫檀芪引起的内质网胁迫并最终抑制了紫檀芪所诱导的细胞凋亡。结论细胞内氧化还原平衡的变化在紫檀芪引起HeLa细胞凋亡的内质网途径方面起了决定性的作用。     

戊地昔布对人胃癌细胞生长的抑制作用

目的　探讨选择性环氧化酶 2 (COX 2 )抑制剂戊地昔布对人胃癌BGC 82 3细胞的作用及其作用机制。方法　用MTT法检测戊地昔布对人胃癌BGC 82 3细胞生长的作用 ,用流氏细胞仪检测细胞凋亡和细胞周期分布 ,用激光共聚焦显微镜、透射电镜和DNA片段进一步检测细胞凋亡 ,用乳酸脱氢酶 (LDH)试剂盒测定BGC 82 3细胞的LDH含量。结果　戊地昔布 (2 5～ 4 0 0 μmol·L-1 )可时间和浓度依赖性抑制人胃癌BGC 82 3细胞的生长 ,作用 72h后 ,对细胞生长抑制率可达 2 4 0 %～ 92 0 % ,凋亡率由 (2 6± 0 7) %增加到 (7 6±1 5 ) %～ (1 6 5± 1 5 ) %。 1 0 0～ 4 0 0 μmol·L-1 也降低增殖指数 ,减少细胞周期S期细胞 ,增加G0 /G1 期细胞。随浓度增加 ,戊地昔布引起的LDH释放率有增加趋势 ,但只有 4 0 0μmol·L-1 戊地昔布可显著增加LDH释放率。结论　戊地昔布可通过诱导凋亡和细胞周期停滞而抑制人胃癌BGC 82 3细胞生长 ,4 0 0 μmol·L-1 戊地昔布抑制BGC 82 3细胞生长作用与细胞坏死有关     

依立雄胺对前列腺癌细胞(LNCaP)前列腺特异性抗原和Bcl-2蛋白体外表达的抑制作用

目的　为研究依立雄胺治疗前列腺癌的可能性及可能机制 ,探讨依立雄胺体外对人激素依赖型前列腺癌细胞 (LNCaP)生长及前列腺特异性抗原(PSA)与Bcl 2蛋白表达的作用。方法　用 5 ,15和4 5 μmol·L- 1的依立雄胺作用LNCaP细胞 3d或 7d后 ,相差显微镜进行细胞形态学观察 ;台盼蓝染色活细胞计数 ,绘制 7d的生长曲线 ;应用流式细胞仪分析依立雄胺对LNCaP细胞凋亡的影响 ;应用免疫组化ABC比较经依立雄胺作用后LNCaP细胞PSA与Bcl 2蛋白的表达强度。结果　 4 5 μmol·L- 1的依立雄胺作用LNCaP细胞 3d后 ,可使其明显的皱缩脱壁 ,部分细胞膜破裂。在 5 ,15和 4 5 μmol·L- 1的依立雄胺作用 7d后 ,可明显抑制LNCaP细胞的生长 ,抑制率分别达 4 0 .0 % ,4 7.4 %和 5 4 .3% ;流式细胞仪分析显示上述浓度的依立雄胺可诱导细胞凋亡 ,凋亡率分别为 3.5 % ,15 .8%和 2 5 .0 % ,而对照组为2 .2 % ;免疫组化分析表明依立雄胺可降低LNCaP细胞PSA和Bcl 2蛋白的表达。结论　在上述浓度下依立雄胺可特异性的抑制LNCaP细胞的生长和PSA与Bcl 2蛋白的表达而诱导细胞凋亡     

紫草素对人宫颈癌HeLa细胞增殖抑制与诱导凋亡的作用研究

目的:研究紫草素对人宫颈癌HeLa细胞增殖抑制与诱导凋亡的作用。方法:10μg/ml紫草素作用于人宫颈癌HeLa细胞,观察细胞的形态学变化;MTT法测定细胞活性,检测紫草素对HeLa细胞的增殖抑制作用;分别测定半胱氨酸天冬氨酸蛋白酶(Caspase)3、8、9的活性,探究细胞凋亡的途径;流式细胞仪测定细胞凋亡率和细胞周期。结果:10μg/ml紫草素可使HeLa细胞部分死亡;1~20μg/ml紫草素可抑制人宫颈癌HeLa细胞的增殖(P<0.01或P<0.05);1、5、10、15、20μg/ml紫草素可增强Caspase-3、8、9的活性(P<0.01或P<0.05);1、5、10、15、20μg/ml紫草素在诱导人宫颈癌HeLa细胞凋亡的同时,阻断了细胞周期的进程,使S期细胞增多。结论:紫草素可抑制HeLa细胞的增殖,诱导细胞凋亡。     

爱普列特对原代培养大鼠输精管上皮细胞及bcl-2表达的影响

目的　探讨爱普列特对原代培养SD大鼠输精管上皮细胞及原癌基因bcl 2表达的影响。方法　应用HE染色、电镜、流式细胞术和免疫组化方法研究爱普列特对输精管上皮细胞形态改变、细胞凋亡率以及bcl 2表达的影响。结果　 0 1 μmol·L- 1 爱普列特对细胞形态无显著影响 ;0 3和 1 0 μmol·L- 1 爱普列特作用 72h后 ,细胞呈核固缩、深染、碎裂、染色质边集等多种形态改变 ,电镜下可见典型的凋亡细胞特征 ;流式细胞仪分析结果显示 ,溶剂对照组细胞凋亡率为 3 42 %± 1 49% ,0 1、0 3和 1 0 μmol·L- 1 爱普列特作用 72h后 ,细胞凋亡率分别为 4 66 %± 2 2 3 % ,39 0 4 %± 1 0 69%和 52 74%± 8 91 % ;免疫组化结果显示输精管上皮细胞bcl 2阳性率为 76 96 %± 9 2 5 % ,0 1、0 3和 1 0 μmol·L- 1 爱普列特作用 72h后 ,Bcl 2阳性表达的百分率分别为 63 93 %± 3 40 %、52 82 %± 8 66 %和 2 9 64 %± 8 74%。结论　 0 1 μmol·L- 1 爱普列特对大鼠输精管上皮细胞无影响 ,0 3和 1 0 μmol·L- 1 可诱导大鼠输精管上皮细胞发生凋亡 ,其作用机制可能与降低bcl 2表达有关     

Shikonin regulates HeLa cell death via caspase-3 activation and blockage of DNA synthesis

Shikonin, isolated from the plant Lithospermum erythrorhizon Sieb. Et Zucc, inhibited tumor cell growth and induced cell death in various tumor cells, with 50% growth inhibition of human cervical cancer cells, HeLa, at 18.9±1.1 μmol L^-1. Treated with 40 μmol L^-1 shikonin, HeLa cells underwent marked apoptotic morphological changes such as a round shape, membrane blebbing and apoptotic bodies derived from the fragmented nuclei. Another hallmark of apoptosis, DNA fragmentation, was observed by gel electrophoresis. Shikonin (10 μmol L^-1) significantly blocked the transition from G1 to S phase in the HeLa cell cycle. Pan-caspase inhibitor (Z-VAD-FMK), caspase-3 inhibitor (Z-DEVD-FMK) or caspase-8 inhibitor (Z-IETD-FMK) effectively inhibited shikonin-induced cell death, while caspase-1 inhibitor (Ac-YVAD-CMK) and caspase-9 inhibitor (Z-LEHD-FMK) failed to affect cell death. Caspase-3 activity significantly increased within 12 h after shikonin treatment. Reduced expression of inhibitor of caspase-activated deoxyribonuclease (ICAD) after exposure to shikonin for 12 h suggests the resultant activation of caspase-activated deoxyribonuclease (CAD), leading to apoptosis.     

紫草素通过ROS/p38信号通路诱导人宫颈癌HeLa细胞凋亡

目的探讨紫草素(shikonin)诱导人宫颈癌HeLa细胞凋亡的机制。方法以MTT法检测shikonin的细胞毒性;相差显微镜观察细胞形态变化;流式细胞仪检测细胞中活性氧(reactive oxygen species,ROS)的产生及凋亡率;Western blot检测相关蛋白的表达。结果 Shikonin时间和剂量依赖性的抑制HeLa细胞的生长;35μmol.L-1的shikonin作用于细胞24 h后可使细胞皱缩、变圆,并出芽形成明显的凋亡小体,且其可时间依赖性的诱导procaspase-3的剪切。35μmol.L-1的shikonin作用于细胞12 h和24 h均可以诱导细胞产生ROS。ROS清除剂NAC和p38抑制剂SB203580可以明显降低shikonin诱导的HeLa细胞的生长抑制和凋亡率;并且5 mmol.L-1 NAC可以上调由shikonin引起的pro-caspase-3的表达降低,下调由shikonin引起的p38蛋白的磷酸化。结论 Shikonin可以诱导HeLa细胞发生凋亡,ROS/p38信号通路参与了其凋亡的过程。     

Oridonin induces apoptosis of HeLa cells via altering expression of Bcl-2 ／ Bax and activating caspase-3 ／ ICAD pathway

INTRODUCTIONHerbal medicine, Donglingcao (rabdosiarubescens), has been traditionally used in China for thetreatment of various diseases such as leukemia.Oridonin (Fig 1) is a diterpenoid compound isolated fromRabdosia rubescens (hemsl). It has various pharmaco-logical and physiological effects such as anti-inflammation, anti-bacteria, anti-tumor[1-3] and has beenused for the treatment of human cancers, especiallyFig 1. Chemical structure of oridonin.esophageal carcinoma[4]. This comp…     

Shikonin, an ingredient of Lithospermum erythrorhizon induced apoptosis in HL60 human premyelocytic leukemia cell line.

Apoptosis is a new therapeutic target of cancer research. Shikonin isolated from Lithospermum erythrorhizon, a traditional oriental medicinal herb, was observed to induce apoptosis in HL60 human premyelocytic leukemia cell line. Shikonin induced DNA fragmentation into the multiples of 180 bp and increased the percentage of hypodiploid cells in flow cytometry after propidium iodide staining. The increase of apoptotic cells was preceded by the activation of caspase-3, which was reported to play a central role in apoptotic process. The DNA fragmentation induced by shikonin was completely inhibited by the pretreatment of z-VAD-fmk, a specific inhibitor of caspase, clearly showing that the mode of cell death is apoptotic.     

Zinc inhibition of caspase-3 activation does not protect HeLa cells from apoptotic cell death

Zinc is proposed to be antiapoptotic for it has been shown to inhibit late events of apoptotic pathways such as Ca(2+)/Mg(2+)-dependent endonuclease cleavage of chromatin DNA, poly-ADP ribose polymerase cleavage, and caspase-3 activity. Because caspase-3 is a critical executioner caspase in apoptosis, this study was undertaken to examine specifically a correlation between zinc inhibition of caspase-3 activation and apoptosis in HeLa cells. Cultured HeLa cells were exposed to 100 microM ZnCl(2) for 1 h prior to 12 h treatment with 1.0 microM doxorubicin (DOX), an important anticancer agent that causes apoptosis in a wide variety of tumor cells. Western blot analysis of HeLa cells treated with DOX for 12 h revealed that DOX caused proteolytic activation of caspase-3 and zinc inhibited this activation. Interestingly, zinc did not inhibit DOX-induced apoptosis as measured by a terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. Furthermore, a microculture tetrazolium assay confirmed that cell death occurred in the presence of zinc. These results demonstrate that zinc specifically inhibits DOX-induced activation of caspase-3 in HeLa cells, but does not suppress DOX-induced apoptosis or otherwise cell death, thus suggesting DOX-induced caspase-3 activation may not play a major role in overall cell death and/or non-caspase-3 pathways are involved in DOX-induced apoptosis in HeLa cells.     

Involvement of mitochondria and caspase pathways in N-demethyl-clarithromycin-induced apoptosis in human cervical cancer HeLa cell

AIM: To study the mechanisms by which N-demethyl-clarithromycin (NDC) induces human cervical cancer HeLa cell apoptosis in vitro. METHODS: The viability of N-demethyl-clarithromycin-induced HeLa cells was measured by MTT assay. Apoptotic cells with condensed nuclei were visualized by phase contrast microscopy. Nucleosomal DNA fragmentation was assayed by agarose gel electrophoresis. Measurement of mitochondrial transmembrane potential was analyzed by a FACScan flowcytometer. Caspase-3, poly-(ADP-ribose) polymerase (PARP), caspase-activated DNase (ICAD), Bcl-2, Bax, p53, and SIRT1 protein expression and the release of cytochrome c were detected by Western blot analysis. RESULTS: N-demethyl-clarithromycin, an anti-inflammatory substance, inhibited HeLa cell growth in a dose- and time-dependent manner. N-demethyl-clarithro-mycin induced HeLa cell death through the apoptotic pathways. The pan-caspase inhibitor (z-VAD-fmk), caspase-3 inhibitor (z-DEVD-fmk) and the caspase-9 inhibitor (z-LEHD-fmk) partially enhanced cell viability induced by N-demethyl-clarithromycin, but the caspase-8 inhibitor (z-IETD-fmk) had almost no effect. Caspase-3 was activated then followed by the degradation of caspase-3 substrates, the inhibitor of ICAD and PARP. Simultaneously, mitochondrial transmembrane potential was markedly reduced and the release of cytochrome c in the cytosol was increased. N-demethyl-clarithromycin upregulated the expression ratio of mitochondrial Bax/Bcl-2, and significantly increased the expression of the p53 protein. It also downregulated anti-apoptotic protein SIRT1 expression. CONCLUSION: N-demethyl-clarithromycin induced apoptosis in HeLa cells via the mitochondrial pathway.     

Diosgenin induces apoptosis in HeLa cells via activation of caspase pathway

AIM: To investigate the mechanism of diosgenin-induced HeLa cell apoptosis. METHODS: HeLa cell growth was measured by MTT method. Apoptosis was detected by electron microscopy and agarose gel electrophoresis. Ratio of apoptotic cells was measured by APO-BRDU kit. Cell cycle distribution and changes of mitochondrial membrane potential were monitored by flow cytometry. Caspase activities were assayed by caspase apoptosis detection kit. Western blot analysis was used to evaluate the level of mitochondrial Bcl-2 expression. RESULTS: Diosgenin inhibited HeLa cell growth. HeLa cells treated with diosgenin showed typical characteristics of apoptosis including the morphological changes and DNA fragmentation. Caspase family inhibitor (z-VAD-fmk), caspase-9 inhibitor (Ac-AAVALPAVLLALLAPLEHD-CHO), and caspase-3 inhibitor (z-DEVD-fmk) partially prevented diosgenin-induced apoptosis, but not caspase-8 inhibitor (z-IETD-fmk) and caspase-10 inhibitor (z-AEVD-fmk). Diosgenin caused reduction of mitochondrial membrane po     

Je-chun-jun induced apoptosis of human cervical carcinoma HeLa cells

AIM: To study the mechanism of Je-Chun-Jun (JCJ)-inducing the apoptosis of the human cervical carcinoma, HeLa cells. METHODS: The cell viability was assessed using MTT assay. The optical density was measured at 570 nm. The caspase activity was measured using 50 mmol/L of fluorogenic substrate, AC-DEVD-AMC (caspase-3), AC-VEID-AMC (caspase-8) or AC-LEHD-AFC (caspase-9). To confirm the expression of proteins, Western blotting was performed. To detect the characteristic of apoptosis chromatin condensation, HeLa cells were stained with Hoechst 33258 in the presence of JCJ. For the cell cycle analysis, HeLa cells were incubated with Propidium iodide (PI) solution. Fluorescence intensity of cell cycle was measured using flow cytometry system. RESULTS: The loss of viability occurred following the exposure of 10 g/L JCJ. Cells treated with 10 g/L JCJ for 3 d exhibited the apoptotic morphology (brightly blue-fluorescent condensed nuclei by Hoechst 33258-staining) and the reduction of cell volume. Cells incubated with JCJ for 48 h were arrested at the G1 phase of cell cycle and their G1 checkpoint related gene products such as cyclin D1 were transiently decreased. We showed that JCJ induced the p38 MAPK activation in HeLa cells. The p38 MAPK inhibitor, SB203580 protected Hela cells from the JCJ-induced death as well as intervened the JCJ-induced accumulation of cells at the G1 phase. In contrast, MEK1 (-ERK upstream) inhibitor, PD98059 had no effect on HeLa cells. CONCLUSION: JCJ induced cell cycle arrest and apoptosis of HeLa cells through p38 MAPK pathway.