小檗碱增强TRAIL诱导白血病细胞凋亡

目的：探讨肿瘤坏死因子相关凋亡诱导配体（TRAIL）联合小檗碱诱导Molt-4细胞凋亡作用及其对NF-κBP65表达的影响。方法：采用四甲基偶氮唑（MTT）比色法测定TRAIL单独和联合应用小檗碱时对Molt-4细胞的生长抑制率；用流式细胞术和光镜细胞形态观察来检测凋亡；应用免疫印迹法检测单独和联合用荮组细胞凋亡相关蛋白酶caspase3，caspase8及NF-κB／P65表达。结果：（1）MTT结果发现小檗碱可增加TRAIL对Molt-4细胞的生长抑制率，且呈时间和剂量依赖性（P〈0．05）。（2）流式细胞术可以检测到凋亡，光镜细胞形态观察可见凋亡特异性形态改变。（3）Western blot结果显示（a）单独用TRAIL组及TRAIL联合小檗碱用药组caspase3，caspase8活化程度随TRAIL质量浓度依次增加，联合用药组活化作用更强。（b）单独用TRAIL组NF-κB／P65表达随剂量增加而增加。联合小檗碱用药组NF-κB／P65表达与单独用TRAIL组相比则明显受抑制。结论：（1）小檗碱可协同TRAIL诱导Molt-4细胞凋亡。（2）小檗碱协同TRAIL诱导Molt-4细胞凋亡的分子机制涉及抑制NF-κB／P65表达和caspase3，caspase8剪切活化。     

小檗碱诱导肿瘤细胞凋亡的研究进展

细胞凋亡（apoptosis）是1972年Kerr等首先提出的一种不同于细胞坏死的细胞死亡方式，又称程序性细胞死亡（programmed cell death，PCD），是指在一定生理和病理情况下．机体为维护内外环境的稳定，细胞对内外信号刺激做出的应答反应。通过基因调控，包括诱导、启动、实施细胞凋亡，是细胞主动消亡的过程。细胞凋亡与增殖是一对并存的矛盾，正常情况是二者维持动态平衡，肿瘤的发生可能与细胞的增殖与死亡的速度平衡失调有关l_1]。目前，许多抗肿瘤药物就是通过干扰肿瘤细胞生长、代谢、增殖等过程，最终触发肿瘤细胞发生凋亡来达到治疗的目的。小檗碱（Berberine）又称黄连素．系从毛莨科黄连属植物黄连根和皮中提取的一种苯并异喹啉类季铵型生物碱，为黄连的主要成分，常用其盐酸盐。黄连味苦、性寒．人心、肝、胃、大肠经．具有清火燥湿、泄火解毒的功效。     

盐酸小檗碱诱导Jurkat细胞凋亡的研究

目的本研究旨在观察盐酸小檗碱能否抑制Jurkat细胞的增殖、并对其作用机制进行初步探讨。从而为临床上应用治疗急性T淋细胞白血病提供实验依据。方法MTT比色法检测盐酸小檗碱对Jurkat细胞增殖的影响;AO／EB染色法观察细胞凋亡的形态学改变;TUNEL方法检测细胞凋亡的生化功能变化。结果盐酸小檗碱对Jurkat细胞的生长有抑制作用,呈现明显的剂量和时间依赖性,24h、48h、72h、96h、120h的IC50分别为107．5567μg·mL^-1、23．5600μg·mL^-1、10．8069μg·mL^-1、9．2660μg·mL^-1和2．7121μg·mL^-1盐酸小檗碱处理Jurkat细胞可见典型的细胞凋亡形态学改变;TUNEL可见深棕色凋亡细胞。结论盐酸小檗碱能有效地抑制体外Jurkat细胞的增殖,其作用可能是通过诱导Jurkat细胞凋亡有关。     

小檗碱诱导人急性T淋巴细胞白血病细胞凋亡的研究

目的探讨小檗碱诱导人急性T淋巴细胞白血病细胞(MOLT-4)凋亡的作用。 方法将处于对数生长期的MOLT-4细胞分为3组，A组加入小檗碱(10，100 mg·L^–1)，B组加入柔红霉素1 mg·L^-1，C组加入小檗碱＋柔红霉素，作用6 和24 h后，用MTT法检测细胞存活率；用流式细胞术、DNA电泳及光学显微镜观察小檗碱对MOLT-4细胞凋亡的影响。结果作用6，24 h后，A组(10 mg·L-¹)细胞存活率分别为81.80%，64.67%； B组为98.38%，38.46%，C组为68.35%，20.51%；C组与A、B组比较，在两个时间段差异均有显著性(P＜0.05)。小檗碱诱导MOLT-4细胞发生典型的细胞凋亡形态学变化，出现DNA规律性断裂，电泳呈典型的梯状条带变化。细胞周期分析提示小檗碱浓度在10，100 mg·L-1时作用24 h细胞凋亡率分别为5.83%，19.93%。结论小檗碱具有诱导白血病细胞凋亡的作用，且小檗碱可增强柔红霉素的抗肿瘤作用，为其临床应用提供了依据。     

小檗碱改善高糖高脂诱导的胰岛NIT-1细胞凋亡的分子机制

目的观察小檗碱对高脂高糖诱导后NIT-1胰岛β细胞凋亡的改善情况,探讨小檗碱抗凋亡的分子机制。方法采用四甲基偶氮唑蓝(MTT)比色法,在培养基中加入高糖高脂及小檗碱共同培养24h后,比较不同浓度的小檗碱对体外培养及高糖高脂诱导的NIT-1胰岛β细胞活力的影响;AnnexinV/PI双标记法流式细胞术检测细胞凋亡情况;RT-PCR法检测凋亡相关基因bcl-2、bax和caspase-3mRNA表达水平;免疫荧光法检测caspase-3表达。结果与正常对照组相比,模型组NIT-1细胞凋亡率明显升高(P<0.01),bcl-2mRNA表达明显降低(P<0.01),而bax和caspase-3mRNA表达明显增高(P<0.01),且胞质caspase-3表达增加;与模型组相比,小檗碱组NIT-1细胞凋亡率明显降低(P<0.01),bcl-2mRNA表达增高(P<0.01),而bax和caspase-3mRNA表达降低(P<0.01),小檗碱组胞质caspase-3表达亦降低。结论小檗碱抑制高糖高脂诱导NIT-1细胞的凋亡可能与其激活bcl-2和抑制bax和caspase-3的表达有关。     

小檗碱对人胃癌MGC-803细胞生长抑制及诱导凋亡的作用

目的　研究小檗碱对胃癌细胞株生长抑制、诱导凋亡作用 ,及其作用浓度、时间与细胞数目、凋亡程度的关系。方法　苔盼蓝细胞计数 ,MTT染色 ,甲基绿 派诺宁染色观察凋亡特征及计数 ,流式细胞仪技术 ,琼脂糖电泳技术分析药物对DNA作用。结果　小檗碱能抑制胃癌细胞MGC 80 3的生长。 8mg·L-1、4mg·L-1、2mg·L-1、1mg·L-1小檗碱 72h的抑制率分别为 10 0 %、80 4%、5 1 5 %、8 5 %。小檗碱作用细胞后 ,细胞表现出较为典型的细胞凋亡形态 :细胞核固缩 ,染色质凝集断裂 ,颗粒含量增加等 ;72h死亡的细胞中抗拒苔盼蓝染色者 ,仍高达 6 0 %～ 82 % ,胞膜完整 ;流式细胞仪DNA直方图上出现典型亚二倍体峰 ;琼脂糖凝胶电泳分析表明 :小檗碱可使染色质断裂 ,且发生于细胞膜结构被破坏之前 ,DNA形成大片段 ,但不形成小片段。结论　小檗碱体外能抑制胃癌MGC 80 3细胞增殖和诱导细胞凋亡 ,其细胞毒性 (致细胞坏死作用 )较弱     

小檗碱对人肺癌GLC-82细胞凋亡的影响

目的探讨生物碱类中药成分小檗碱(berber-ine)诱导人肺癌GLC-82细胞的凋亡作用。方法采用细胞培养技术,用不同浓度的小檗碱处理GLC-82细胞48h,用Hoechst33258染细胞核,在荧光显微镜下观察凋亡细胞核的形态变化,用QWin图象分析软件测量细胞核面积,计算凋亡率。采用MTT法测定细胞的增殖能力。小檗碱作用GLC-82细胞36h后,采用荧光免疫细胞化学SABC-Cy3法测定Caspase-3和PARP蛋白表达,在荧光显微镜下拍照,用QWin图象分析软件测定Caspase-3和PARP荧光强度值。结果小檗碱剂量依赖性的抑制GLC-82细胞增殖,半数生长抑制剂量IC50为19.9mg·L-1,上调凋亡促进因子Caspase-3,PARP蛋白表达增加,使GLC-82细胞呈现典型的凋亡形态学特征,胞核缩小,核质浓集,呈斑块状,有凋亡小体。结论小檗碱通过上调Caspase-3诱导人肺癌GLC-82细胞凋亡。     

盐酸小檗碱增敏柔红霉素诱导儿童急性淋巴细胞白血病原代细胞凋亡作用的研究

目的:探讨盐酸小檗碱(BBR)增敏柔红霉素(DNR)诱导儿童急性淋巴细胞白血病原代细胞(P-ALLCs)凋亡的作用及相关机制。方法:收集初诊初治的急性淋巴细胞白血病(ALL)儿童骨髓标本12例,分离单个核细胞,按活细胞数2×10^5/m L接种于含20%小牛血清1640的96孔培养板,培养4 h后按照设定DNR 4个浓度和BBR 3个浓度单药及交叉联合应用方案加入不同体积的PBS稀释DNR和BBR储备液培养干预24 h,采用cell counting kit-8 assay(CCK-8)检测DNR和BBR单药作用以及两者联合作用对P-ALLCs增殖的抑制作用。结果:DNR单药作用时抑制率为(11.56%±0.73%)^{59.60%±2.80%},随着DNR浓度的增加,P-ALLCs的增殖抑制逐渐增强,且后一浓度与前一浓度比较差异均有统计学意义(P均<0.05);BBR单药作用时抑制率为(12.39%±1.50%)^{39.75%±2.43%},随着BBR浓度的增加,P-ALLCs的增殖抑制逐渐增强,且后一浓度与前一浓度比较差异均有统计学意义(P均<0.05);DNR联合BBR时的抑制率为(18.43%±1.11%)^{89.96%±1.40%}。在4个联合用药组中,随着BBR浓度的增加,对P-ALLCs的增殖抑制逐渐增强(P均<0.05),而且每一组中DNR联合BBR后的抑制率比DNR单药作用强(P均<0.05)。结论:DNR和BBR对儿童P-ALLCs均有细胞毒性作用并成浓度依赖性。两药联合作用时BBR可以增加P-ALLCs对DNR的敏感性,该作用与浓度有一定的相关性。     

辛伐他汀通过线粒体途径诱导K562细胞凋亡

目的观察辛伐他汀诱导K562细胞凋亡不同时间的膜电位(Δψm),caspase-3、9和细胞色素C的改变,以推测其凋亡通路。方法采用浓度为20μmol.L-1的辛伐他汀处理K562细胞24、48、72 h,采用流式细胞技术检测细胞凋亡率和线粒体膜电位,分光光度法检测caspase-3、9蛋白活性,免疫组织化学法检测细胞色素C蛋白。结果浓度为20μmol.L-1辛伐他汀作用K562细胞24、48、72 h后,凋亡率分别为(6.1±0.35)%、(14.15±0.42)%(、30.70±0.65)%,随着凋亡率增加线粒体膜电位降低分别为(39.6±4.80)%,(24.4±2.45)%,(6.0±1.62)%;caspase-3、9蛋白活性与对照组相比上调,细胞浆内细胞色素C升高。结论辛伐他汀诱导K562细胞凋亡时线粒体膜电位下降,caspase-3、9活性增高和细胞色素C释放,推测辛伐他汀诱导K562细胞的凋亡可能经过线粒体凋亡途径。     

黄连小檗碱对人肠癌Caco-2细胞凋亡和细胞周期的影响

目的探讨黄连小檗碱对人肠癌细胞株Caco-2细胞周期和细胞凋亡的影响及其作用机制。方法采用MTT法,检测不同时间点不同浓度黄连小檗碱对Caco-2细胞的增殖抑制作用;应用流式细胞术(Annexin V-FITC/PI双染法),检测不同浓度黄连小檗碱对Caco-2细胞周期和凋亡的影响。结果不同浓度的黄连小檗碱干预肠癌细胞Caco-2不同时间后,均具有一定的增殖抑制作用,在一定浓度范围内,可以剂量和时间依赖性的抑制Caco-2细胞增殖。黄连小檗碱干预细胞24 h后,可使Caco-2细胞停滞在G2/M期,诱导细胞凋亡(P<0.05)。结论黄连小檗碱可以显著抑制Caco-2细胞增殖,其作用机制可能与阻滞细胞周期从而诱导细胞凋亡有关。     

大黄素诱导人肝癌HepG2细胞线粒体凋亡作用研究

目的 研究大黄素对人肝癌HepG2细胞线粒体凋亡的影响。方法 培养人肝癌HepG2细胞,与5、10、20、40、60、80、100 μmol/L的大黄素作用24、48 h,MTS法检测细胞增殖;40、80、160 μmol/L大黄素作用HepG2细胞24 h,AO/EB双荧光染色法观察细胞凋亡的形态学改变;Annexin V/PI染色经流式细胞仪检测细胞凋亡;分光光度法检测caspase 3活性;ATP试剂盒检测细胞ATP含量,不同荧光探针加载后流式细胞仪测定大黄素对HepG2细胞内活性氧（ROS）含量、Ca²⁺浓度、线粒体膜电位（MMP）变化的影响。结果 大黄素抑制HepG2细胞生长,且呈时间、浓度相关性,半数抑制浓度（IC₅₀）为（77.42±1.25）μmol/L;随着大黄素浓度升高,AO/EB双染观察到细胞核浓缩、碎裂、凋亡小体等凋亡形态;与对照组比较,大黄素40、80、160 μmol/L作用于HepG2细胞24 h后细胞凋亡率显著增加,caspase 3活性显著增强,ROS水平、Ca²⁺浓度明显增加（P<0.05、0.01、0.001）,80、160 μmol/L组线粒体膜电位明显降低,ATP含量显著下降（P<0.05、0.01、0.001）。结论 大黄素造成HepG2细胞内ROS堆积,ATP合成功能障碍,线粒体膜电位明显下降,进而诱导线粒体通透转运孔开放,导致钙离子和细胞色素C外流,活化caspase蛋白家族,导致细胞凋亡。     

Indole-3-carbinol induces apoptosis in AGS cancer cells via mitochondrial pathway

Indole-3-carbinol is produced from the cruciferous vegetables and broadly investigated for their various biological effects in in-vitro and in-vivo aspects. However, the anticancer activity of I3C and its molecular mechanisms have not been investigated in human adeno gastro carcinoma (AGS) cells. In our study of AGS cells, nuclear condensation was observed by 4′,6-diamidino-2-phenylindole (DAPI) staining, cell death was confirmed by a cell viability assay, and fragmented DNA was observed at the IC₅₀ dose by a DNA fragmentation assay. Apoptosis was evaluated by the qPCR technique. Treatment of the AGS cells with I3C at different concentrations has drastically decreased cell proliferation and differentiation. By releasing cytochrome-c from mitochondria in the intrinsic pathway, I3C prevents the multiplication of AGS cells and initiates apoptosis. The WST-1 assay result showed that I3C treatment against AGS cells had considerably reduced the viability of the cells. Furthermore, RT-qPCR showed the fold change among the expressed proteins compared with reference gene β-actin. Molecular docking revealed that I3C showed a strong binding affinity for the apoptotic protein 3DCY. The results show the caspase group of proteins contribute to the core of apoptotic machinery. I3C and its metabolites target a variety of components of cell-cycle control via distinct signaling pathways in light of the rapid development of tumors and oncogenesis. The translational significance of I3C and its metabolites in cancer is highlighted by their wide range of antitumor activity and low toxicity. Furthermore, the novel prodrug I3C, which has overlapping underlying mechanisms, could encourage new strategies to decrease oncogenesis.     

Osthole induces human nasopharyngeal cancer cells apoptosis through Fas–Fas ligand and mitochondrial pathway

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and Southeast Asia. The present study investigated the activity of osthole in suppressing NPC along with the underlying mechanism. Cell growth inhibition was measured using the MTT assay. Apoptosis was detected through 4ʹ,6‐diamidino‐2‐phenylindole staining and flow cytometry. Western blotting was used to identify the signaling pathway. Osthole markedly inhibited cell proliferation and induced apoptosis in the NPC cell line. Western blotting results revealed the increased activation of caspases 3, 8, and 9 and poly (ADP‐ribose) polymerase. Osthole treatment significantly reduced the expression of the antiapoptotic protein Bcl‐2 and increased the expression of the proapoptotic proteins Bax, Bak, BimL, BimS, and t‐Bid. Osthole treatment also increased the expression of Fas, FADD, TNF‐R1, TNF‐R2, DcR2, RIP, and DR5. In addition, osthole treatment significantly increased the expression levels of phosphorylated ERK1/2 and JNK1/2. These results suggested that osthole exerts cytotoxic effects on NPC cell lines mainly through apoptosis mediated by the Fas–Fas ligand and mitochondrial pathway. Osthole could be a potential anticancer agent for NPC.     

Arsenic induces apoptosis by the lysosomal‐mitochondrial pathway in INS‐1 cells

Recently, long term arsenic exposure was considered to be associated with an increased risk of diabetes mellitus. While a relation of cause‐and‐effect between apoptosis of pancreatic β‐cells and arsenic exposure, the precise mechanisms of these events remains unclear. The aim of this study was to explore arsenic‐induced pancreatic β‐cell apoptosis and the mechanisms of through the possible link between lysosomal and the mitochondrial apoptotic pathway. After exposure to 10 μM of arsenic, the reactive oxygen species (ROS) level was significantly increased at 12 h, while the mitochondrial membrane potential was reduced at 24 h and the lysosomal membrane integrity was disrupted at 48 h. A significant increase in protein expression for cytochrome c was also observed using Western blot analysis after exposure to arsenic for 48 h. To further demonstrate that arsenic reduced the lysosomal membrane integrity, cells pretreated with NH₄Cl and exposed to arsenic harbored a lower fluorescence increase than cells that were only exposed to arsenic. In addition, apoptosis was mesured using Hoechst 33342/PI dual staining by microscopy and annexin V‐FITC/propidium iodide dual staining by flow cytometry. The results show an increased uptake of the arsenic dose and the cells changed from dark blue to light blue, karyopyknosis, nuclear chromatin condensation, side set or fracture, and a correlation was found between the number of apoptotic cells and arsenic dose. The result of present study suggest that arsenic may induce pancreatic β‐cell apoptosis through activation of the lysosome‐mitochondrial pathway. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 133–141, 2016.     

Glycoborinine induces apoptosis through mitochondrial pathway in HepG2 cells

Glycoborinine (GB), a natural carbazole alkaloid isolated from Glycosmis pentaphylla, has been shown to be a potential molecule against cancer cells. In this study, the cell-signaling pathway of its anti-tumor activity was investigated. MTT assay result showed that GB inhibited HepG2 cell proliferation in a dose- and time-dependent manner and 50% inhibiting concentration (IC₅₀) of GB-induced cell death was 39.7 μM for a period of 48 h. GB-induced HepG2 apoptosis was confirmed by Hochest 33258 staining and PI staining. The level of reactive oxygen species (ROS) was measured with H₂DCF-DA staining and the change of mitochondrial membrane potential (△Ψ^m) was analyzed with tetrechloro-tetraethylbenzimidazolcarbocyanine iodide (JC-1) probe. Results showed that GB at 12.5, 25, and 50 μM promoted ROS production. GB induced HepG2 apoptosis through a mitochondrial apoptotic pathway, which was demonstrated by GB-induced increase in the ratio of Bax/Bcl-2, cytochrome C release, the ratio of cleaved caspase-3/procaspase-3, and the ratio of cleaved poly ADP-ribose polymerase (cleaved PARP)/poly ADP-ribose polymerase (PARP). To summarize, this study demonstrated that GB could induce HepG2 apoptosis through the mitochondrial-dependent pathway, which might provide a promising approach to cure liver cancer with GB.     

Role of the mitochondrial membrane permeability transition (MPT) in rotenone-induced apoptosis in liver cells.

Rotenone inhibits spontaneously and chemically induced hepatic tumorigenesis in rodents through the induction of apoptosis. However, the mechanism for the induction of apoptosis by rotenone has not been defined. Mitochondrial dysfunction, in particular the induction of the mitochondrial membrane permeability transition (MPT), has been implicated in the cascade of events involved in the induction of apoptosis. Inhibition of the mitochondrial electron-transport chain reduces the mitochondrial transmembrane potential (delta(psi)m), which may induce the formation of the mitochondrial permeability transition pore and the subsequent MPT. Fluorescent microscopy of Hoechst 33258-stained WB-F344 cells, a rat-liver cell line, was utilized to examine the effect of the mitochondrial respiratory chain inhibitor, rotenone (0.5-5 microM), atractyloside (5-10 microM), and cyclosporin A (2.5-10 microM) on apoptosis. A time- and concentration-dependent increase in liver cell apoptosis was observed following treatment with rotenone and atractyloside (11.7- and 7.7-fold, respectively, over solvent control). Cotreatment with 7.5- and 10 microM-cyclosporin A for 12 h inhibited the apoptogenicity of 5-microM rotenone treatment. A similar effect was observed following cyclosporin A cotreatment with atractyloside. Rotenone induced a rapid increase in apoptosis (within 20 min of treatment). By 2 h of treatment, the morphological appearance of apoptosis was similar to that observed in cultures treated continuously with rotenone for 12 h. Inhibition studies demonstrated that cyclosporin A prevented apoptosis if the exposure to it occurred prior to the 20-min threshold necessary to induce apoptosis by rotenone. Mitochondrial function was examined by staining with the mitochondrial membrane potential (delta(psi)m)-sensitive fluorochrome, MitoTracker Red (CMXRos) and confirmed utilizing cytofluorometric analysis of DiOC6(3)-stained cells. Rotenone (5.0-microM) and atractyloside (5.0-microM) reduced the percent of CMXRos or DiOC6(3)-positive (delta(psi)m-positive) liver cells within 15 min and throughout the duration of the study (6 h) to approximately 65-80% and 50-80% of control. However, cotreatment with concentrations of cyclosporin A that inhibited the apoptogenicity of rotenone and atractyloside prevented the rotenone- and atractyloside-induced reduction of the delta(psi)m. Therefore, the apoptogenic effect of rotenone and atractyloside appears to occur rapidly (within 20 min) and is irreversible once mitochondrial damage occurs. The inhibition of the rotenone- and atractyloside-induced apoptosis and mitochondrial dysfunction by cyclosporin A suggests the MPT may be involved in the induction of apoptosis by rotenone.     

嵌合抗CD20抗体Fab′片段诱导Raji细胞凋亡过程中活性氧自由基的变化

目的　研究嵌合抗CD2 0抗体Fab′片段对B淋巴细胞株Raji细胞活性氧自由基 (ROS)的影响。 方法　利用MTT法测定Fab′片段抑制细胞生长 ,形态学方法和DNA琼脂糖凝胶电泳法观察Fab′片段对细胞凋亡的影响 ,用DCFH DA和双氢罗丹明 1 2 3(DHR )标记细胞内活性氧(ROS)变化 ,并用流式细胞仪检测。结果　MTT法测定抗CD2 0抗体Fab′片段对Raji细胞的生长具有抑制作用 ,其抑制作用呈明显的剂量依赖性 ,电镜观察 ,可见“凋亡小体”出现 ,DNA电泳可见典型的“梯形”条带 ,抗CD2 0抗体Fab′片段能增加Raji细胞内ROS水平 ,且随浓度增加而增加。 结论　ROS水平升高在抗CD2 0抗体Fab′片段诱导Raji细胞凋亡的过程中起到重要作用     

Atorvastatin induces mitochondrial dysfunction and cell apoptosis in HepG2 cells via inhibition of the Nrf2 pathway

Atorvastatin (ATO) is a 3‐hydroxy‐3‐methylglutaryl‐CoA reductase inhibitor widely used to treat hypercholesterolemia. However, clinical application is limited by potential hepatotoxicity. Nuclear factor‐erythroid 2‐related factor 2 (Nrf2) is a master regulator of cellular antioxidants, and oxidative stress is implicated in statin‐induced liver injury. This study investigated mechanisms of ATO‐induced hepatotoxicity and potential mitigation by Nrf2 signaling. ATO reduced Nrf2 and antioxidant enzyme superoxide dismutase‐2 (SOD2) expression in human hepatocarcinoma HepG2 cells. ATO also induced concentration‐dependent HepG2 cell toxicity, reactive oxygen species (ROS) accumulation, and mitochondrial dysfunction as evidenced by decreased mitochondrial membrane potential (MMP) and cellular adenosine triphosphate (ATP). Further, ATO induced mitochondria‐dependent apoptosis as indicated by increased Bax/Bcl‐2 ratio, cleaved caspase‐3, mitochondrial cytochrome c release and Annexin V‐fluorescein isothiocyanate/propidium iodide staining. Tert‐butylhydroquinone enhanced Nrf2 and SOD2 expression, and partially reversed ATO‐induced cytotoxicity, ROS accumulation, MMP reduction, ATP depletion and mitochondria‐dependent apoptosis. In conclusion, the present study demonstrates that ATO induces mitochondrial dysfunction and cell apoptosis in HepG2 cells, at least in part, via inhibition of the Nrf2 pathway. Nrf2 pathway activation is a potential prevention for ATO‐induced liver injury.     

Fisetin induces apoptosis through mitochondrial apoptosis pathway in human uveal melanoma cells

Fisetin, a diatery flavonoid, been reported that possess anticancer effects in various cancers. The purpose of the study was to investigate the antitumor effects of fisetin in cultured uveal melanoma cell lines and compared with normal retinal pigment epithelial (RPE) cells. MTT assay was used for evaluating cytotoxic effects of fisetin. Flow cytometry study was used for the determination of apoptosis. JC‐1 fluorescent reader was used to determine mitochondrial transmembrane potential changes. The results shown that fisetin dose‐dependently decreased the cell viability of uveal melanoma cells but not influenced the cell viability of RPE cells. Apoptosis of uveal melanoma cells was induced by fisetin efficiently. Fisetin inhibited antiapoptotic Bcl‐2 family proteins and damaged the mitochondrial transmembrane potential. The levels of proapoptotic Bcl‐2 proteins, cytochrome c, and various caspase activities were increased by fisetin. In conclusion, fisetin induces apoptosis of uveal melanoma cells selectively and may be a promising agent to be explored for the treatment of uveal melanoma.