Taxol对宫颈癌U14细胞增殖、凋亡及α2,6-SA和ST6Gal mRNA表达的影响

目的:研究泰素(Taxol)对小鼠宫颈癌U14细胞株增殖、凋亡以及α2,6-唾液酸(SA)和α2,6-唾液酸转移酶(ST6Gal)mRNA表达的影响,为进一步探讨宫颈癌Taxol化疗机制提供新思路。方法:Taxol处理U14细胞后,MTT检测Taxol对U14细胞的IC_(50)值。流式细胞术检测细胞α2,6-SA、细胞凋亡相关因子(Bcl-2、Bax、caspase8和caspase 3)、凋亡率和细胞周期改变。qPCR检测ST6Gal1和ST6Gal2 mRNA的表达。结果:与对照组相比,Taxol对U14细胞有明显的抑制作用,减弱α2,6-SA荧光强度,上调Bax表达,下调Bcl-2表达,降低Bcl-2/Bax比值,并增强caspase 8和caspase 3活性;Taxol处理显著增加U14细胞凋亡率及S期细胞和G2/M期细胞比率,此外还下调ST6Gal1 mRNA表达。结论:α2,6-SA和ST6Gal可能参与了Taxol对U14细胞细胞周期和凋亡调控的多重作用。     

苦碟子对恶性黑色素瘤细胞抑制及凋亡蛋白Bcl-2/Bax表达的影响

目的观察不同浓度中药苦碟子对恶性B16黑色素瘤细胞的抑制作用和凋亡蛋白Bcl-2/Bax表达的变化,探讨中药苦碟子抑制B16黑色素瘤细胞生长的可能机制。方法通过细胞培养和MTT实验,检测苦碟子对B16黑色素瘤细胞的生长抑制情况,Western blot测定凋亡蛋白Bcl-2/Bax表达,免疫荧光染色检测Bcl-2/Bax蛋白在不同浓度苦碟子处理的黑色素瘤细胞中的表达。透射电镜观察不同浓度梯度中药苦碟子诱导细胞凋亡,其细胞结构的特征性变化。结果随着苦碟子药物浓度的增加,黑色素瘤细胞活细胞数目逐渐减少,细胞存活率显著下降(<0.05),凋亡抑制蛋白Bcl-2表达水平呈现下降趋势,而促凋亡蛋白Bax呈现上升趋势(<0.05),免疫荧光染色显示Bcl-2表达逐渐减少,Bax表达逐渐增加;电镜下凋亡小体数目不断增加,核固缩逐渐明显,细胞间隙增大,线粒体数目减少。结论中药苦碟子有浓度依赖性抑制黑色素瘤细胞生长,促进细胞凋亡,凋亡蛋白Bcl-2/Bax变化呈线性关系。     

Nodosin对HepG2细胞株的增殖抑制作用及对Bcl-2和Bax表达的影响

 目的:研究传统中药提取物nodosin对体外培养的人肝癌细胞株HepG2的增殖抑制作用,并探讨其对Bcl-2和Bax表达的影响。方法:将不同浓度组（1.25、2.5、5、10和20 μmol/L）nodosin预作用于HepG2细胞24 h,用倒置显微镜观察nodosin对细胞形态学的影响,采用MTT法检测细胞生长抑制率,用流式细胞术检测细胞凋亡率和Bcl-2、Bax的表达。结果:形态学结果显示,随着nodosin剂量的增加,细胞皱缩和漂浮细胞数量增加,流式细胞术检测结果显示随着nodosin药物浓度的增加,HepG2细胞凋亡率增加。Bax的表达随着nodosin剂量的增加逐渐增加, Bcl-2的表达逐渐减少。结论: Nodosin能抑制HepG2细胞株的增殖,呈明显的剂量依赖性,对HepG2细胞的抑制作用是通过增加Bax的表达以及降低Bcl-2的表达诱导细胞凋亡实现的。     

芹菜素对人肺癌A549细胞凋亡及相关蛋白Bax、Bcl-2表达的影响

目的研究芹菜素对人肺癌 A549细胞增殖抑制和凋亡诱导作用与 Bax、Bcl-2蛋白表达的影响。方法10~80μmol/L 不同浓度芹菜素作用 A549细胞,采用 MTT 法检测芹菜素对 A549细胞增殖抑制作用;Hoechst 33258细胞核染色法观察芹菜素诱导细胞凋亡形态学的变化;流式细胞仪 AnnexinV- FITC/PI 双染色法检测细胞凋亡率;Western blot 法检测凋亡相关蛋白 Bax 和 Bcl-2表达的变化。结果 MTT 法显示,芹菜素对 A549细胞有显著的增殖抑制作用（P <0.01）,且具浓度和时间依赖性;荧光显微镜下观察到芹菜素处理组细胞出现典型的凋亡形态学改变：细胞核固缩、染色质凝集和核碎片化等;流式细胞仪分析结果显示,芹菜素呈浓度依赖性诱导 A549细胞凋亡;Western blot结果显示,促凋亡蛋白 Bax 随着芹菜素浓度升高表达增加,抗凋亡蛋白 Bcl-2随着芹菜素浓度升高表达减少。结论芹菜素具有抑制人肺癌 A549细胞增殖,诱导其凋亡的作用,其机制可能与上调 Bax 蛋白表达和下调 Bcl-2蛋白表达有关。     

Apoptosis in adriamycin cardiomyopathy and its modulation by probucol

The dose-dependent cardiomyopathy and heart failure due to adriamycin have been shown to be due to increased oxidative stress and loss of myocytes. We examined the incidence of myocardial apoptosis as well as changes in the expression of apoptotic regulatory gene products in an established animal model of adriamycin cardiomyopathy. Rats were treated with adriamycin (cumulative dose, 15 mg/kg), and the hearts were examined for apoptosis as well as expression of Bax, caspase 3, and Bcl-2 at 0, 4, 10, 16, and 21 days after the treatment. A significant increase in the incidence of apoptosis was seen at 4 days, followed by a decline at 10 and 16 days of posttreatment. At 21 days, the number of apoptotic cells increased again and included cells of the conducting system. Expression of Bax corresponded to these biphasic changes, whereas the converse was true for the expression of Bcl-2. The latter peaked at 10 days followed by a decline at 16 and 21 days. The Bax/Bcl-2 ratio also correlated with the incidence of apoptosis. Expression of caspase 3 correlated with increased apoptosis, but only at early time points. Probucol (cumulative dose, 120 mg/kg), a known antioxidant as well as promoter of endogenous antioxidants, significantly reduced the incidence of apoptosis as well as expression of Bax. Adriamycin-induced hemodynamic changes were also prevented by probucol. These data suggest that adriamycin-induced apoptosis is mediated by oxidative stress and may play a role in the development of heart failure.     

银杏内酯B对体外培养的大鼠视网膜神经细胞凋亡的影响

目的： 观察银杏内酯B对体外培养的大鼠视网膜神经细胞凋亡的影响及可能的作用机制。 方法： 采用体外原代培养的大鼠视网膜神经细胞，建立谷氨酸损伤的视网膜神经细胞凋亡模型，与不同浓度的银杏内酯B（ginkgolide B，GB）共同培养，用MTT法测定神经细胞存活率；流式细胞仪检测神经细胞凋亡及其相关基因Bcl-2和Bax蛋白表达。 结果： 谷氨酸（0.8 mmol/L）作用后，视网膜神经细胞存活率降低。GB不同时间及不同剂量作用组与谷氨酸处理组比较，视网膜神经细胞内Bcl-2和Bax阳性蛋白表达及两者比值均有显著差异（P＜0.01），细胞凋亡明显减少。 结论： GB能剂量依赖性对抗谷氨酸兴奋性毒性, 保护视网膜神经细胞，这一作用可能是通过促进Bcl-2蛋白表达并减少Bax蛋白表达，上调Bcl-2/Bax比值而抑制视网膜神经细胞凋亡来实现的。     

NADH对L02细胞Bcl-2、Bax、P53、CD95及CD95L表达的影响

目的：研究抗氧化剂NADH对体外培养的正常人肝细胞系L02缺血再灌注损伤的保护作用及可能的机制。方法：实验分组：将培养的L02细胞分为：缺血再灌注损伤组（I／R），缺血再灌注损伤＋NADH（I／R＋NADH）及对照组（未经处理的L02细胞）。用流式细胞仪观察细胞处理后6、12、18及24h细胞的凋亡率及12h时，Bcl-2、Bax、P53、CD95及CD95L的表达，并以透射电镜观察细胞凋亡的超微结构。结果：NADH可明显抑制缺血再灌注损伤细胞的凋亡，并能上调Bcl-2表达，下调Bax、P53、CD95及CD95L的表达，与I／R组相比较差异显著（P＜0．05）。透射电镜下可见典型的凋亡细胞的特征。结论：NADH对缺血再灌注损伤诱导的L02肝细胞有明显地保护作用。其作用机制可能与通过调节Bcl-2、Bax、P53、CD95及CD95L的表达有关。     

Protective effect of ultra low molecular weight heparin on glutamate-induced apoptosis in cortical cells

PURPOSE: To investigate the effect of ultra low molecular weight heparin (ULMWH) on glutamate induced apoptosis in rat cortical cells and to explore the possible mechanisms. MATERIALS AND METHODS: Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptosis was first analyzed with Hoechst 33258 and then confirmed by DNA fragmentation. The concentration of free intracellular calcium ([Ca(2+)](i)) was determined with fura-2/AM fluorometry. The expression of Bcl-2 family protein and caspase-3 were evaluated with Western blot. RESULTS: Typical apoptotic morphological change in rat cortical cells treated with 100 micromol/L glutamate for 24h was detected by Hoechst 33258 staining, which was then confirmed by the DNA ladder of agarose gel electrophoresis. The apoptotic rate of the glutamate treated cells was up to 33.21%, and 24 h of treatment with glutamate increased [Ca(2+)](i), down-regulated Bcl-2 expression, up-regulated Bax expression, and increased caspase-3 activation in rat cortical cells. Our research demonstrated that ULMWH pretreatment can prevent the glutamate-induced apoptosis, attenuate the increase of [Ca(2+)](i) not only in medium containing Ca(2+) but also in Ca(2+)-free medium, up-regulate the expression of Bcl-2, down-regulate the expression of Bax, and decrease caspase-3 activation. CONCLUSION: ULMWH has neuroprotective capacity to antagonize glutamate-induced apoptosis in cortical cells, through decrease of Ca(2+) release and modulation of apoptotic processes.     

C5b-9 terminal complement complex assembly on apoptotic cells in human arterial wall with atherosclerosis

Apoptosis plays an important role in atherosclerosis. The factors regulating this process are not well defined. We examined the relation of apoptotic cells with the terminal complement complex C5b-9 in human atherosclerotic lesions. The extent of apoptosis was determined using TdT dUTP nick-end labeling (TUNEL) and immunohistochemistry of apoptosis regulators caspase-3, caspase-9, Bax, and Bcl-2. C5b-9 was localized by immunohistochemistry and immunoelectron microscopy. The apoptotic index was higher in fibrous plaques when compared with intimal fatty streaks and intimal thickenings. Bax expression was present in TUNEL+ apoptotic cells, and Bcl-2 was rarely present in the atherosclerotic wall. Active caspase 9 and caspase 3 deposits were present in the same areas, suggesting an involvement of the mitochondrial pathway. C5b-9 deposits colocalized with TUNEL+ cells, and the percent of double-positive cells was 2% in fatty streaks, 12% in intimal thickenings, and 35% in fibrous plaques. Colocalization of apoptotic cells with C5b-9 was also confirmed by immunoelectron microscopy. In conclusion, some apoptotic cells carry C5b-9 deposits, suggesting that complement might be activated by apoptotic cells and involved in the promotion of apoptosis, contributing to the progression of atherosclerotic lesions.     

人参皂苷Rh4诱导肝癌细胞HepG2的凋亡及分子机制

目的:探讨人参皂苷Rh4对人肝癌HepG2细胞凋亡的作用及机制。方法:采用MTT比色法测定不同浓度(10、20和40μmol/L)人参皂苷Rh4对人肝癌HepG2细胞活力的抑制作用;用流式细胞术检测定细胞凋亡率;通过Hoechst 33258和TUNEL染色观察人参皂苷Rh4诱导人肝癌HepG2细胞凋亡的形态学变化;Western blot法检测凋亡相关蛋白Bax、Bcl-2、caspase-3和caspase-9的表达情况。结果:人参皂苷Rh4能够明显促进人肝癌HepG2细胞的凋亡,且呈剂量依赖性;TUNEL和Hoechst 33258染色实验结果表明,人参皂苷Rh4作用24 h后,细胞呈现明显皱缩、肿胀、破裂等凋亡形态;Western blot分析结果表明,随着人参皂苷Rh4给药浓度的增加,抗凋亡蛋白Bcl-2表达量逐渐下降,而促凋亡蛋白Bax、cleaved caspase-3和caspase-9的表达逐渐升高。结论:人参皂苷Rh4可诱导人肝癌HepG2细胞凋亡,其作用机制可能与下调Bcl-2以及上调Bax、cleaved caspase-3和caspase-9蛋白表达有关。     

Quantification of Bax/Bcl-2 ratios in peripheral blood lymphocytes, monocytes and granulocytes and their relation to susceptibility to anti-Fas (anti-CD95)-induced apoptosis

Neutrophils have the shortest half-life among circulating leucocytes and rapidly undergo apoptosis in vitro. The homologous Bcl-2 and Bax proteins have opposing effects, with Bcl-2 extending cellular survival and Bax promoting cell death following an apoptotic stimulus. We determined Bcl-2 to Bax expression ratios in peripheral blood lymphocytes, monocytes and granulocytes and related them to the susceptibility of these cells to anti-Fas (anti-CD95)-induced apoptosis. Here, we show that Bax/Bcl-2 ratios are high in granulocytes and relatively low in monocytes and lymphocytes. Furthermore, we show a relation between this ratio in the different leucocyte subsets and their susceptibility to anti-Fas-induced apoptosis, with granulocytes showing the highest susceptibility, followed by monocytes and lymphocytes. It is concluded that the balance between Bcl-2 and Bax forms an apoptotic rheostat, which seems to determine sensitivity to apoptosis.     

乙醇诱导的肝癌细胞HCC—9204凋亡及其与Bax和Bcl—2蛋白的关系

目的 探讨乙醇对肝癌细胞凋亡的诱导作用及其与凋良心相关基因bax和 bcl-2表达的关系。方法 用噻唑蓝（MTT）法检测浓度分别为20-100mL-L的乙醇对肝癌细胞系HCC-9204的杀伤作用,然后,用60mL/L乙醇作用6h诱导HCC——9204细胞凋亡,以May-Grunwald-Giemsa(MGG)染色法、末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）法和流式细胞术分别分析凋亡细胞的形态学变化、DNA断裂情况和不同细胞周期的DNA含量变化,用免疫细胞化学染色图象分析法,检测诱导凋亡前、后Bax和Bcl-2蛋白表达水平的变化。结果 随着乙醇浓度的增加,其对HCC-9204细胞的杀伤作用逐渐增强,60mL/L乙醇可使HCC-9204细胞发生明显的细胞凋亡的形态学变化,并且大部分细胞为TUNEL阳性着色,流式细胞术分析可见明显的亚二倍体凋亡峰,诱导凋亡后的HCC-9204细胞Bax蛋白的表达水平明显增高,而Bcl-2在诱导凋亡前、后的HCC——9204细胞中均未见表达,结论 低浓度乙醇对肝癌细胞HCC——9204具有明显的凋亡诱导作用,其凋亡的发生与Bax蛋白表达水平的增高有关。     

Mild traumatic brain injury induces apoptotic cell death in the cortex that is preceded by decreases in cellular Bcl-2 immunoreactivity

Although mild traumatic brain injury is associated with behavioral dysfunction and histopathological alterations, few studies have assessed the temporal pattern of regional apoptosis following mild brain injury. Anesthetized rats were subjected to mild lateral fluid-percussion brain injury (1.1–1.3 atm), and brains were evaluated for the presence of in situ DNA fragmentation (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling, TUNEL) and morphologic characteristics of apoptotic cell death (nuclear and cytoplasmic condensation, presence of apoptotic bodies). Significant numbers of apoptotic TUNEL(+) cells were observed in the injured parietal cortex and underlying white matter up to 72 h post-injury (P<0.05 compared to sham-injured-injured), with maximal numbers present at 24 h. Apoptosis was confirmed by the presence of 180–200 bp nuclear DNA fragments in tissue homogenates. The appearance of apoptotic TUNEL(+) cells in the injured cortex was preceded by a marked decrease in immunoreactivity for the anti-cell death protein, Bcl-2, as early as 2 h post-injury. This decrease in cellular Bcl-2 staining was not accompanied by a concomitant loss of staining for the pro-cell death Bax protein, suggesting that post-traumatic neuronal death in the cortex may be dependent on altered cellular ratios of Bcl-2:Bax. In the hippocampus, no significant increase in apoptotic TUNEL(+) cells was observed compared to sham-injured-injured animals. However, selective neuronal loss was evident in the CA3 region at 24 h post-injury, that was preceded by an overt loss of neuronal Bcl-2 immunoreactivity at 6 h. No changes in either cellular Bcl-2 or Bax expression were observed in the thalamus or white matter at any time post-injury.

Taken together from these data, we suggest that apoptosis contributes to cell death in both gray and white matter, and that decreases in cellular Bcl-2 may, in part, be associated with both apoptotic and non-apoptotic cell death following mild brain trauma.     

西兰花多肽组分II诱导神经胶质瘤细胞凋亡的作用及其机制研究

 目的：探讨西兰花多肽组分II诱导胶质瘤细胞凋亡的作用及机制。方法：培养人神经胶质瘤SHG-44细胞,将其分为对照组以及3、10、30和100 mg/L西兰花多肽组分II组,MTT法检测西兰花多肽组分II作用后细胞活力的变化;Annexin V/PI 检测细胞的凋亡率;倒置显微镜观察西兰花多肽组分II诱导细胞凋亡的形态学变化;免疫细胞化学和Western blotting法检测西兰花多肽组分II作用后Bax、Bcl-2蛋白表达,Western blotting法检测caspase-3蛋白表达。结果：西兰花多肽组分II作用SHG-44细胞24 h 、48 h和72 h时均可以降低细胞活力,作用呈时间-剂量依赖性。Annexin V/PI 检测细胞凋亡率发现,各用药组细胞凋亡率随着药物剂量的增加而显著升高。倒置显微镜下观察,西兰花多肽组分II作用SHG-44细胞72 h后,各用药组细胞的密度随药物浓度升高而明显降低,并可见到明显的凋亡小体。细胞免疫组织化学和Western blotting结果显示,药物作用SHG-44细胞72 h后,与对照组比较,细胞Bax蛋白表达呈上升趋势,Bcl-2蛋白表达呈下降趋势,各用药组Bax/Bcl-2比值均明显增加（P<0.05或P<0.01）;Western blotting检测caspase-3蛋白发现,各药物组caspase-3蛋白表达量均增加,与空白对照组比较,30和100 mg/L西兰花多肽组分II组差异有统计学意义（P<0.01）。结论：西兰花多肽组分II可提高神经胶质瘤细胞中Bax/Bcl-2蛋白的比值,促进caspase-3蛋白活化,从而诱导肿瘤细胞凋亡。     

越桔原花青素调控脑胶质瘤细胞生长的机制研究*

 目的： 探讨越桔原花青素对脑胶质瘤细胞生长的影响。方法: 培养脑胶质瘤C6细胞,将其分为对照组以及10、20和40 μg/L越桔原花青素组,MTT法检测药物对C6细胞生长的影响,倒置显微镜观察细胞生长的变化,Annexin V/PI染色检测细胞凋亡率的变化,免疫细胞化学法检测Bcl-2与Bax蛋白表达,Western blotting检测Bcl-2、Bax和caspase-3蛋白表达。结果: 在24、48和72 h时,10、20和40 μg/L越桔原花青素均抑制C6细胞的生长,24和48 h时40 μg/L越桔原花青素组、72 h时20和40 μg/L越桔原花青素组细胞生长明显受抑制 (均P＜0. 01);倒置显微镜观察发现,各药物组细胞密度随药物浓度升高而减少;Annexin V/PI分析显示,细胞的凋亡率亦随着药物浓度的增加而明显增加;细胞免疫组化结果显示,10、20和40 μg/L越桔原花青素组中,C6细胞表达Bcl-2蛋白减少,表达Bax蛋白增加,但均无明显差异;Bax/Bcl-2的比值随着药物浓度升高而增加（P＜0.05或P＜0.01）; Western blotting结果显示,10、20和40 μg/L越桔原花青素组中,随着药物浓度升高,细胞表达Bcl-2蛋白减少（P＜0.01）而Bax和caspase-3蛋白表达均增加,Bax/Bcl-2的比值也明显增加（P＜0.01）。结论: 越桔原花青素抑制脑胶质瘤C6细胞的生长,其作用机制与调控Bax蛋白增加和Bcl-2蛋白减少,使Bax/Bcl-2比值增加,从而激活caspase-3,诱导凋亡发生有关。     

人参皂苷Rh2对人骨肉瘤细胞MG-63凋亡的影响

目的:探讨人参皂苷Rh2对人骨肉瘤细胞MG-63凋亡的影响,并初步探讨可能的分子机制。方法:采用流式细胞术Annexin V-PI双染法和MTT法检测MG-63细胞的凋亡变化;免疫印迹法检测Bcl-2、Bax、Cyt C和激活型caspase-3的蛋白水平。结果:流式细胞术和MTT法结果显示人参皂苷Rh2呈浓度依赖性促进MG-63细胞的凋亡。免疫印迹法结果表明,与空白对照组相比,给药组细胞Bax的蛋白表达显著增加,Bcl-2的蛋白表达显著减少,Bcl-2/Bax比值减少;线粒体中Cyt C蛋白表达显著减少,而胞浆中表达显著增加;激活型caspase-3蛋白水平显著增加(P0.05)。结论:人参皂苷Rh2呈浓度依赖性促进MG-63细胞的凋亡,其凋亡过程可能与调控线粒体凋亡通路相关蛋白有关。     

创伤后应激障碍大鼠海马神经元凋亡的形态学变化及相关基因表达

目的 探讨创伤后应激障碍(PTSD)大鼠海马神经元Bcl-2和Bax的表达及与神经元凋亡的关系.方法 采用国际认定的SPS方法刺激大鼠建立PTSD大鼠模型,取SPS刺激后1d、4d、7d、14d组和正常对照组.应用透射电镜和原位末端标记法观察PTSD大鼠海马神经元细胞凋亡的形态学变化并检测细胞凋亡指数;应用免疫组织化学、免疫荧光双标、激光共焦显微镜技术和免疫印迹法检测Bel-2和Bax蛋白的表达. 结果 PTSD大鼠海马神经元出现细胞凋亡改变;凋亡细胞数量随时问的延长而逐渐增多,于SPS刺激后7d达高峰;Bel-2蛋白于SPS刺激后4d达高峰;Bax蛋白于SPS刺激后7d达高峰,之后逐渐下降.Bcl-2/Bax的比值于SPS刺激后一过性增加,以后随时间延长比值下降. 结论海马神经元细胞凋亡可能是PTSD大鼠海马萎缩的原因之一;Bel-2和Bax蛋白含量增加以及两者的比值失衡可能是导致PTSD大鼠海马神经元凋亡的原因之一.     

蜕皮甾酮减轻心肌细胞氧化应激损伤

目的:研究蜕皮甾酮对心肌细胞氧化损伤的作用。方法:H9c2细胞常规培养,经过氧化氢(H_2O_2)处理后建立损伤模型,分为:对照组,蜕皮甾酮高剂量(2μmol/L)、中剂量(1.5μmol/L)和低剂量(1μmol/L)组,H_2O_2组。CCK-8法检测蜕皮甾酮对H9c2细胞活力的影响;流式细胞术检测H9c2细胞的凋亡率;用分光光度法检测乳酸脱氢酶、肌酸激酶同工酶的活性以及丙二醛、超氧化物歧化酶含量;激光共聚焦联合流式细胞术观察细胞内活性氧簇(ROS)的产生和线粒体膜电位的变化;用Western blot法检测H9c2细胞内Bax、Bcl-2和cleaved caspase-3的蛋白水平。结果:在所选浓度范围内,蜕皮甾酮对H9c2细胞的活力无明显影响。与对照组比较,H_2O_2组H9c2细胞的LDH、CK-MB、ROS、MDA及凋亡率明显增加,通过不同浓度的蜕皮甾酮作用后,H9c2细胞的LDH、CK-MB、ROS、MDA及凋亡率显著下降,与H_2O_2组比较差异有统计学显著性。与对照组比较,H_2O_2组H9c2细胞的SOD和线粒体膜电位明显下降;与H_2O_2组比较,蜕皮甾酮高、中、低剂量组H9c2细胞的SOD和线粒体膜电位明显提高。对比对照组,H_2O_2组中H9c2细胞Bax和cleaved caspase-3的蛋白水平明显升高,Bcl-2的表达水平明显下降;与H_2O_2组比较,蜕皮甾酮高、中、低剂量组中H9c2心肌细胞表达Bcl-2蛋白上升,Bax和cleaved caspase-3的蛋白水平下降。结论:蜕皮甾酮对氧化应激条件下的H9c2细胞具有保护功能,其机制可能和减少氧化应激产物,增强抗氧化酶功能,调节线粒体功能和抑制细胞凋亡相关。     

热休克蛋白70在缺糖损伤的HeLa细胞中对Bax和Bcl-2以及Bax构象改变的影响

目的 观察热休克蛋白70(Hsp70)对缺糖引起的HeLa细胞凋亡的影响,探讨其与凋亡相关的Bcl-2家族成员的相互作用关系. 方法 用人正义Hsp70重组质粒稳定转染HeLa细胞获得Hsp70过表达细胞.采用Hsp70过表达和正常HeLa细胞无糖培养建立两组细胞损伤模型,并均取3个平行样本.四甲基偶氮唑盐(MTT)法测细胞活率;Hoechst染色法和Giemsa染色法检测细胞凋亡率;RT-PCR法检测Bax和Bcl-2的表达变化,并计算其灰度比值;细胞免疫化学和荧光免疫法检测Bax构象改变情况. 结果 缺糖48h内,Hsp70明显抑制了HeLa细胞凋亡并增强其活力,同时也抑制了凋亡细胞中 Bax/Bcl-2的增高以及Bax的构象改变. 结论 缺糖诱导下,热休克蛋白70在HeLa细胞中能够通过与Bcl-2家族成员作用而抑制凋亡的发生.