LSC-DC-CIK对慢性粒细胞白血病干细胞杀伤作用的体外试验研究

目的 研究慢性粒细胞白血病(CML)患者来源的干细胞体外扩增诱导生成树突细胞(DC),与同来源的细胞因子诱导的杀伤细胞(CIK)共培养,对慢性粒细胞白血病细胞株K562干细胞的杀伤作用.方法 提取CML患者的骨髓单个核细胞(BMMC),利用流式细胞术(FCM)分选纯化白血病干细胞(LSC)CD34+CD38-CD44+,体外扩增诱导生成LSC-DC.取同一患者骨髓的BMMC诱导出CIK.LSC-DC与CIK共培养,用光学显微镜观察细胞形态,FCM分析LSC-DC和CIK细胞免疫表型,荧光原位杂交(FISH)检测BCR/ABL融合基因在LSC及LSC-DC中的表达,FCM检测LSC-DC-CIK对慢性粒细胞白血病细胞株K562干细胞的杀伤及凋亡情况.结果 白血病干细胞能成功诱导为LSC-DC,其DC成熟免疫表型CD40、CD80、CD83、CD86及受体(HLA-DR)的表达均高于诱导前;共培养后CIK表面标志CD3、CDs、CD56的表达率高于单独培养CIK,差异有统计学意义(P＜0.01).LSC-DC与CIK共培养后对慢性粒细胞白血病细胞株K562干细胞的杀伤率(66.94％)明显高于单独培养的CIK(31.89％),差异有统计学意义(P＜0.01).LSC-DC-CIK可诱导K562细胞凋亡,凋亡率为52.28％±3.71％,与CIK组(37.51％±1.89％)相比,差异有统计学意义(P＜0.01);但对其中白血病干细胞无明显的诱导凋亡作用.结论 CML来源LSC-DC保留有干细胞特征,其与CIK共培养能杀伤慢性粒细胞白血病细胞株干细胞,但无明显的诱导干细胞凋亡作用.     

苦参碱联合阿霉素对耐药白血病K562／AO2细胞株凋亡及Bel-2表达的影响

目的研究苦参碱联合阿霉素对耐药白血病细胞系K562／AO2体外增殖的抑制、诱导凋亡及对Bcl-2表达的影响。方法实验分对照组,阿霉素组,苦参碱组（又分为0．50mg／ml、0．75mg／ml、1．0mg／ml3个不同的浓度组）和苦参碱＋阿霉素组（也根据苦参碱的浓度不同分为0．50mg／ml、0．75mg／ml、1．0mg／ml3个不同的浓度组）,共分为8个组。取对数生长的肿瘤细胞,1×10^6／孔,分别加入阿霉素、不同浓度的苦参碱,不同浓度的苦参碱联合阿霉素予以处理,对照组只加等体积的培养基不加药物。加入药物后继续培养48小时。以MTr法检测肿瘤细胞增殖的抑制率,流式细胞术检测肿瘤细胞凋亡、Bcl-2表达。结果单纯阿霉素组、单纯苦参碱组、苦参碱＋阿霉素组对K562／A02细胞系均有抑制作用;随苦参碱浓度的增高,抑制作用增强,各组间差异有统计学意义（P〈0．01）;苦参碱＋阿霉素组的细胞抑制率均显著高于单纯苦参碱组和单纯阿霉素组,差异有统计学意义（P〈0．01）。苦参碱组及苦参碱联合阿霉素组K562／A02细胞凋亡率较对照组明显升高,差异有统计学意义（P〈0．01）;苦参碱＋阿霉素组的细胞凋亡率较单纯苦参碱组及单纯阿霉素组均显著升高,差异有统计学意义（P〈0．01）,并且随苦参碱浓度的增加,细胞凋亡率增加。各单纯组及联合组细胞Bcl-2的阳性表达率与对照组相比均明显下调,差异有统计学意义（P〈0．05）;苦参碱＋阿霉索组细胞Bcl-2表达率与单纯苦参碱组、单纯阿霉素组相比均明显下调,差异有统计学意义（P〈0．05）。结论苦参碱与阿霉素联合能增强对K562／AO2细胞的抑制作用,促进其凋亡,明显降低Bcl-2表达。     

黄芪多糖对人红白血病K562细胞凋亡的影响

目的:探讨黄芪多糖(简称APS)对人红白血病K562细胞凋亡产生的影响。方法:经流式细胞术来研究APS对人红白血病K562细胞凋亡产生的影响,而APS在K562细胞之中对Caspase-3产生的影响可通过Caspase-3活性测定法进行检测;经Westernblot以及RT-PCR对对照组(K562细胞)及APS组(通过200mg/L的APS进行48h诱导形成的K562细胞)之中的Bcl-X_L、Bcl-2、IAP-1、Bax、SmacmRNA和蛋白进行表达。结果:APS组细胞凋亡数量相较于对照组更高,两组有显性差异,有统计学意义,P0.05;APS组K562细胞中的Caspase-3相较于对照组明显增加,但IAP-1及Bcl-2的mRNA和蛋白的表达都显示降低,而Smac以及Bax的mRNA和蛋白的表达均明显增加,两组有显性差异,有统计学意义,P0.05;两组在Bcl-X_L的mRNA和蛋白方面的表达无显性差异,无统计学意义,P0.05。结论:APS对人红白血病K562细胞进行诱导凋亡可能是通过对Smac、Bax上调以及对IAP-1、Bcl-2下调来实现的。     

1，25-二羟基维生素D3对K562细胞周期及凋亡的影响

目的观察1，25-二羟基维生素D3[1，25（OH）2D3]对白血病细胞株K562细胞周期及细胞凋亡的作用。方法Western印迹检测维生素D受体（VDR）在K562细胞的表达；四噻唑蓝法（MTT）、AO／EB、流式细胞仪分析细胞生长抑制率、细胞凋亡率及细胞周期。结果（1）K562细胞核阳性表达VDR；（2）0-10^-6mol／L浓度的1，25（OH）2D3呈浓度依赖性抑制K562细胞增殖，10^-8mol／L 1，25（OH）2D3明显抑制K562细胞增殖，促进凋亡，细胞周期阻滞主要发生在G2期或M早期，凋亡率从4．1％（对照组）增至26．5％（P〈0．01）。结论1，25（OH）2D3可明显抑制K562细胞增殖，促进细胞凋亡。     

4-邻氨基酚-4＇去甲表鬼臼酯（ODE）在K562肿瘤细胞凋亡中的作用

目的 研究不同浓度4-邻氨基酚-4＇去甲表鬼臼酯（ODE）对肿瘤细胞生长的影响,探讨ODE诱导肿瘤细胞凋亡的机制.方法 采用MTT法测定ODE对K562细胞生长的抑制作用,透射电镜观察细胞超微结构,免疫细胞化学方法检测K562细胞中 Bcl-2/Bax 比率变化.结果 （1）不同浓度ODE对K562细胞生长有抑制作用,随ODE浓度的增加及作用时间的延长细胞生长抑制率增高（P〈0.05）;（2）透射电镜观察可见凋亡细胞发生;（3）凋亡细胞中Bcl-2灰度较正常细胞染色的灰度低,Bax在凋亡细胞中的灰度较正常细胞高.结论 ODE能够显著抑制K562细胞的生长,其抑制作用随浓度的增加及时间的延长而增强,通过形态学可观察到凋亡细胞的产生,其诱导凋亡可能是通过改变凋亡基因而发挥作用的.     

急性淋巴细胞白血病患儿骨髓间充质干细胞对K562细胞株药物耐受性的影响

Objective To study the effect of acute lymphoblastic leukemia (ALL) children bone marrow mesenchymal stem cells (MSCs) on the resistance of K562cell atd mechanism in vitro.Method MSCs were obtained from AL children bone marrow after derivation, cultivation and identification.The coculture of MSCs and K562 and K562 suspension were established.Effects of MSCs on the growth of K562 cells were investigated in vivo.The two kinds of cells treated with different concentration of adriamycin (ADM) and the rate of apoptosis was evaluated by flow cytometry.Cell cycle was determined by flow cytometry.RT-PCR was used to detect Bcl-2 and Bax in K562 cells.Result Compared with the cell growth curve of K562 alone, the K562 cell co-cultured with MSCs grew slower and the exponential phase of growth was not obvious.The apoptosis index of the K562 cells co- clutured with MSCs was (9.19 ±0.53)% examined by flow cytometry, and that of the K562 cells alone was 4.00 ± 0.37% respectively( P ＜ 0.05 ).The percentage of cells at G0/G1 phase was (50.2 ± 2.26) % and that at S phase was (37.03 ± 3.50) % in the group of K562 alone, but those of the K562 cells co - cultured with MSCs were (80.95 ± 3.83) % and ( 17.40 ± 1.50)% respectively( P ＜0.05).The result of RT-PCR suggested expression of Bcl-2/Bax of the K562 cell co-cultured with MSCs was higher than K562 alone.Conclusion ALL children MSCs suppressed the growth of K562 cell in vitro.Adhesion made K562 depress sensitive to ADM.The mechanism was perhaps caused by adhesion with MSCs, K562 cell cycle was changed and related to Bcl-2 gene high level expression.     

三氧化二砷联用华蟾素对K562细胞增殖和凋亡的影响

目的 研究三氧化二砷联用华蟾素对K562细胞增殖和凋亡的影响,为三氧化二砷和华蟾素联合应用于临床提供理论依据.方法 细胞增殖采用细胞生长及活力测定;细胞凋亡采用细胞形态、Annexin-V/PI双染实验、DNA的PI染色及DNA电泳等方法 测定.结果 在三氧化二砷和华蟾素作用下K562细胞生长受抑伴随活力下降,1.0 μmol/L As2O3、0.125μg/rnl华蟾素、0.25 μg/ml华蟾素、1.0 μmol/L As2O3＋0.125μg/ml华蟾素、1.0 μmol/L As2O3＋0.25μg/ml华蟾素作用K562细胞24 h和48 h后,增殖抑制率分别为（24±1.3）%、（21±1.5）%、（38±3.1）%、（57±2.7）%、（66±3.3）%及（49±2.9）%、（48±2.7）%、（61±2.1）%、（77±3.8）%、（82±4.2）%,细胞凋亡率分别为（4.8±0.5）%、（5.6±0.7）%、（9.8±0.6）%、（11.9±1.2）%、（15.2±1.5）%及（11.0±0.9）%、（12.9±1.1）%、（18.4±1.5）%、（21.0±2.0）%、（28.0±1.9）%,凋亡细胞百分率呈时间剂量依赖关系;基因组DNA电泳出现＂梯＂状条带.结论 三氧化二砷和华蟾素均有抑制K562细胞增殖和诱导该细胞凋亡的作用,两药联用效果更佳.     

急性淋巴细胞白血病患儿骨髓间充质干细胞对K562细胞株药物耐受性的影响

Objective To study the effect of acute lymphoblastic leukemia (ALL) children bone marrow mesenchymal stem cells (MSCs) on the resistance of K562cell atd mechanism in vitro.Method MSCs were obtained from AL children bone marrow after derivation, cultivation and identification.The coculture of MSCs and K562 and K562 suspension were established.Effects of MSCs on the growth of K562 cells were investigated in vivo.The two kinds of cells treated with different concentration of adriamycin (ADM) and the rate of apoptosis was evaluated by flow cytometry.Cell cycle was determined by flow cytometry.RT-PCR was used to detect Bcl-2 and Bax in K562 cells.Result Compared with the cell growth curve of K562 alone, the K562 cell co-cultured with MSCs grew slower and the exponential phase of growth was not obvious.The apoptosis index of the K562 cells co- clutured with MSCs was (9.19 ±0.53)% examined by flow cytometry, and that of the K562 cells alone was 4.00 ± 0.37% respectively( P ＜ 0.05 ).The percentage of cells at G0/G1 phase was (50.2 ± 2.26) % and that at S phase was (37.03 ± 3.50) % in the group of K562 alone, but those of the K562 cells co - cultured with MSCs were (80.95 ± 3.83) % and ( 17.40 ± 1.50)% respectively( P ＜0.05).The result of RT-PCR suggested expression of Bcl-2/Bax of the K562 cell co-cultured with MSCs was higher than K562 alone.Conclusion ALL children MSCs suppressed the growth of K562 cell in vitro.Adhesion made K562 depress sensitive to ADM.The mechanism was perhaps caused by adhesion with MSCs, K562 cell cycle was changed and related to Bcl-2 gene high level expression.     

苦参碱联合阿霉素对耐药白血病K562/AO2细胞株凋亡及Bcl-2表达的影响

目的研究苦参碱联合阿霉素对耐药白血病细胞系K562/AO2体外增殖的抑制、诱导凋亡及对Bcl-2表达的影响。方法实验分对照组,阿霉素组,苦参碱组(又分为0.50 mg/ml、0.75 mg/ml、1.0mg/ml 3个不同的浓度组)和苦参碱+阿霉素组(也根据苦参碱的浓度不同分为0.50 mg/ml、0.75 mg/ml、1.0mg/ml 3个不同的浓度组),共分为8个组。取对数生长的肿瘤细胞,1×106/孔,分别加入阿霉素、不同浓度的苦参碱,不同浓度的苦参碱联合阿霉素予以处理,对照组只加等体积的培养基不加药物。加入药物后继续培养48小时。以MTT法检测肿瘤细胞增殖的抑制率,流式细胞术检测肿瘤细胞凋亡、Bcl-2表达。结果单纯阿霉素组、单纯苦参碱组、苦参碱+阿霉素组对K562/AO2细胞系均有抑制作用;随苦参碱浓度的增高,抑制作用增强,各组间差异有统计学意义(P0.01);苦参碱+阿霉素组的细胞抑制率均显著高于单纯苦参碱组和单纯阿霉素组,差异有统计学意义(P0.01)。苦参碱组及苦参碱联合阿霉素组K562/AO2细胞凋亡率较对照组明显升高,差异有统计学意义(P0.01);苦参碱+阿霉素组的细胞凋亡率较单纯苦参碱组及单纯阿霉素组均显著升高,差异有统计学意义(P0.01),并且随苦参碱浓度的增加,细胞凋亡率增加。各单纯组及联合组细胞Bcl-2的阳性表达率与对照组相比均明显下调,差异有统计学意义(P0.05);苦参碱+阿霉素组细胞Bcl-2表达率与单纯苦参碱组、单纯阿霉素组相比均明显下调,差异有统计学意义(P0.05)。结论苦参碱与阿霉素联合能增强对K562/AO2细胞的抑制作用,促进其凋亡,明显降低Bcl-2表达。     

高碘对甲状腺损伤调控机理的研究

以高碘水喂养豚鼠180天复制出高碘甲状腺肿模型,应用流式细胞术及免疫荧光染色方法检测高碘对甲状腺细胞凋亡、细胞周期的影响,对Bcl-2,Bax表达的影响及与细胞凋亡的相关性,探讨高碘对甲状腺损伤的调控机理。结果显示：（1）高碘可引起甲状腺细胞周期改变诱导其细胞凋亡的发生。（2）高碘可引起甲状腺bcl-2表达下调,Bax过度及Bcl-2/Bax比值降低（P＜0．01）。（3）高碘所引起的Bcl-2表达及Bcl-2/Bax比值改变与细胞凋亡有明显的相关性（P＜0．05）。结果表明,高碘可能通过引起Bcl-2,Bax表达及Bcl-2/Bax比值的改变而诱导甲状腺细胞过度凋亡,进而对其结构及功能造成损伤。     

黄芪联合顺铂对喉癌Hep-2细胞的体外抑制作用

目的 研究黄芪与顺铂联合对体外培养的人喉癌Hep-2细胞的抑制作用.方法 用MTT法检测黄芪、顺铂单独或联合作用对人喉癌Hep-2细胞的抑制率;用流式细胞技术及Western-blotting法检测黄芪、顺铂单独或联合作用对人喉癌Hep-2细胞凋亡的影响.结果 作用24h后黄芪组、顺铂组、黄芪联合顺铂组对Hep-2细胞的抑制率分别为(53.83±17.12)％、(69.12±27.12)％、(84.55±27.84)％,与对照组(0％)比较差异有统计学意义(t=16.87,16.67,40.90,P＜0.01).黄芪组、顺铂组、黄芪联合顺铂组Hep-2细胞的凋亡率[(38.2±13.6)％、(67.2±17.8)％、(86.4±25.1)％]与对照组[(17.1±1.3)％]比较差异有统计学意义(t =8.11,12.77,24.92,P＜0.05),且联合用药组的效果较任一单独用药组更为明显(t=11.33,9.37,P＜0.01).结论 黄芪通过促进细胞凋亡有效提高顺铂对Hep-2细胞抑制作用的敏感性,通过调节Bcl-2/Bax蛋白表达,能提高顺铂对喉癌的治疗效果.     

石蒜碱诱导结肠癌HT-29 细胞凋亡机制研究

目的 探讨石蒜碱诱导结肠癌HT-29 细胞凋亡及机制。方法 不同浓度的石蒜碱处理体外结肠癌HT-29 细胞,CCK-8法检测细胞活力,流式细胞仪和Hoechst 33258染色法检测细胞凋亡;Real time PCR实验检测Caspase-3、Bcl-2和Bax的mRNA水平;Western blot方法检测Caspase-3、Bcl-2和Bax蛋白的水平。结果 48h时石蒜碱对HT-29 细胞IC50为8.878μmol/L;与对照组比较,1.25μmol/L、2.5μmol/L、5μmol/L石蒜碱能诱导细胞凋亡(P<0.05),上调Caspase-3、Bax的mRNA和Caspase-3、Bax蛋白水平,下调Bcl-2的mRNA和Bcl-2蛋白水平,差异均有统计学意义(P<0.05)。结论 石蒜碱能通过调节Caspase-3、Bcl-2、Bax的表达水平,抑制结肠癌HT-29 细胞生长,诱导细胞凋亡,具有明显的体内抗肿瘤作用。     

吡柔比星联合二烯丙三硫抑制膀胱癌细胞生长的协同作用研究

目的探讨吡柔比星(THP)联合二烯丙三硫(DATS)对膀胱癌细胞T24的协同杀伤效应及其机制。方法 MTT法、TUNEL法、流式细胞仪分别检测THP、DATS及二者联合对T24细胞生长、细胞周期及凋亡的影响;western-blot测定Bcl-2、Bax的表达变化;比色法测定caspase-3活性。结果 THP、DATS均能抑制T24细胞生长,DATS可明显提高THP的杀伤效应;THP(0.25mg/L)联合DATS(3mg/L)作用48h的细胞生存率为(32.3±2.6)%,低于单独应用THP(63.2±1.4)%和DATS(61.9±4.2)%,二者具有协同抑瘤作用;联合药物组可明显提高细胞凋亡率及G2/M期细胞比率,并更能显著抑制Bcl-2的表达,促进caspase-3的活性增加。结论 THP联合DATS可通过共同诱导肿瘤细胞凋亡发挥协同作用,抑制膀胱癌细胞生长,该机制可能与细胞周期阻滞、Bcl-2的表达及caspase-3的活性变化有关。     

二甲双胍联合阿帕替尼对胃癌细胞的增殖抑制作用

目的 探讨二甲双胍联合阿帕替尼对胃癌BGC823细胞系的增殖抑制作用及其可能的机制。方法 MTT法检测不同浓度二甲双胍（0～30 mmol/L)、不同浓度阿帕替尼（0～60 μmol/L）及两药联合应用处理BGC823细胞24、48、72 h的增殖抑制率,结晶紫染色法检测细胞集落形成能力,流式细胞术检测细胞凋亡,western blot检测细胞中血管内皮生长因子信号通路及凋亡相关蛋白VEGFR2、PI3K、p - AKT、AKT、Bax、Bcl - 2表达水平。结果 二甲双胍和阿帕替尼单独处理BGC823后,细胞增殖抑制率均增加（P＜0.05）,联合用药产生协同作用（CI＜1）,二甲双胍和阿帕替尼单独及联合应用均能抑制细胞集落形成并使总凋亡比例增加（P＜0.05）。与对照组和单药组相比,联合用药可明显下调细胞中VEGFR2、PI3K、p - AKT、AKT、Bcl - 2蛋白的表达水平,上调Bax蛋白表达水平（P＜0.05）。结论 二甲双胍联合阿帕替尼具有协同抑制胃癌BGC823细胞增殖和诱导细胞凋亡的作用,其机制可能与抑制VEGF信号通路有关。     

枸杞多糖对人前列腺癌PC-3细胞的影响及其抑瘤效应

目的探讨枸杞多糖(Lycium barbarum polysaccharide,LBP)对人前列腺癌PC-3细胞的影响及其机制,观察LBP对人前列腺癌PC-3细胞致瘤作用的干预效果。方法通过细胞生长抑制率、彗星实验、流式细胞术、原位末端标记法(TUNEL)和Bcl-2、Bax蛋白表达来检测LBP对人前列腺癌PC-3细胞的影响;致瘤性实验检测LBP对人前列腺癌PC-3细胞致瘤力的影响。结果LBP能抑制人前列腺癌PC-3细胞的生长;可致PC-3细胞DNA链断裂;能诱导PC-3细胞凋亡;使Bcl-2/Bax蛋白比值显著下降;LBP干预组肿瘤体积增长缓慢,肿瘤体积和重量均明显小于和轻于人前列腺癌裸鼠移植模型组。结论LBP对抗人前列腺癌PC-3细胞和肿瘤生长抑制作用的机制,可能与其损伤人前列腺癌PC-3细胞DNA链、诱导细胞凋亡和调控凋亡相关基因表达有关。     

The role of dietary fatty acids in predicting myocardial structure in fat-fed rats

Background

The purpose of this study was to identify the affect on the proliferation Eca-109 cells treated with oxidized low-density lipoprotein (ox-LDL) combined with adriamycin (ADM).

Methods

Eca-109 cell were cultured in the presence of oxLDL/ADM, and cell proliferation tested by MTT and cell apoptosis was monitored by the proportion of apoptosis and cell cycle by flow cytomester. We simultaneously evaluated the level of associated- apoptosis Bcl-2, Bax, and Caspase-3 gene mRNA and protein.

Results

OxLDL were cytotoxic and activate apoptosis. OxLDL combined with ADM significant enhanced the proportion rate of apoptosis on a time and dose dependency. The expressions of the inhibiting apoptosis Bcl-2 gene mRNA and protein were down regulated, whereas, the expressions of the promoting apoptosis Bax, and Caspase-3 genes mRNA and protein were up regulation.

Conclusion

These results suggested that oxLDL have cytotoxicity and activate apoptosis on the Eca-109 cells. OxLDL combined with ADM have a synergistic effect on the apoptosis induced Eca-109 cells. Furthermore, oxLDL may contribute to the improvement of clinical chemotherapy of cancer need to make further investigation.     

氢醌对人白血病细胞凋亡及相关蛋白Bcl-2、Bax及Caspase-3表达的影响

目的 研究氢醌对白血病细胞株U937细胞凋亡及相关蛋白Bcl-2、Bax及Caspase-3表达的影响。方法 用不同浓度的氢醌处理U937细胞24 h、48 h后,采用MTT法来检测细胞增殖抑制率;经瑞-吉染色后,观察细胞形态变化;采用流式细胞仪检测细胞凋亡;采用免疫印迹法检测Bcl-2、Bax及Caspase-3蛋白表达。结果 (1)U937细胞的增殖抑制率随氢醌作用时间及浓度的增加而增加,呈时间-剂量依赖性(P<0.05);(2)氢醌作用后,部分细胞体积增大,胞浆中有空泡,胞核发生畸形;(3)流式细胞术结果显示,细胞凋亡率随着氢醌作用时间及浓度的增加而增加,呈时间-剂量依赖性(P<0.05);(4)免疫印迹结果显示,与空白组相比较,染毒48h时,细胞Bax蛋白的表达量增加(P<0.05),而Bcl-2蛋白表达量减少(P<0.05),Bcl-2/Bax比值下降(P<0.05),染毒24 h时,细胞Caspase-3蛋白的表达量增加(P<0.05);与染毒24 h各组相比较,染毒48 h时细胞Caspase-3蛋白的表达量随时间延长呈增加趋势(P<0.05)。结论 氢醌可以诱导U937细胞凋亡,其机制可能与调控凋亡相关蛋白Bcl-2、Bax及Caspase-3的表达有关。     

2,5-hexanedione induced apoptosis in mesenchymal stem cells from rat bone marrow via mitochondria-dependent caspase-3 pathway

2,5-hexanedione (HD) induces apoptosis of nerve cells. However,the mechanism of HD-induced apoptosis remains unknown. Mesenchymal stem cells (MSCs) are multipotential stem cells with the ability to differentiate into various cell types. This study is designed to investigate the apoptosis induced by HD in rat bone marrow MSCs (BMSCs) and the related underlying mechanisms. The fifth generation of MSCs was treated with 0, 10, 20 and 40 mM HD respectively. The viability of BMSCs was observed by MTT. Apoptosis were estimated by Hoechst 33342 staining and TUNEL assay. The disruption of mitochondrial transmembrane potential (MMP) was examined by JC-1 staining. Moreover, the expression of Bax and Bcl-2, cytochrome c release, and caspase-3 activity were determined by real-time RT-PCR, Western blot and Spectrophotometry. Our results showed that HD induced apoptosis in MSCs in a dose dependent manner. Moreover, HD downregulated the Bcl-2 expression,upregulated the Bax expression and the Bax/Bcl-2 ratio, promoted the disruption of MMP, induced the release of cytochrome c from mitochondria to cytosol, and increased the activity of caspase-3 in MSCs. These results indicate that HD induces apoptosis in MSCs and the activated mitochondria-dependent caspase-3 pathway may be involved in the HD-induced apoptosis.