A purified extract from Clematis mandshurica prevents staurosporin-induced downregulation of 14-3-3 and subsequent apoptosis on rat chondrocytes

OBJECTIVE: To dissect the mechanism of the protection of staurosporin-induced apoptosis on rat chondrocytes by a purified extract from Clematis mandshurica. DESIGN: Primary cultured rat articular chondrocytes as well as RCJ3.1C.18 cells were incubated with 1 microM staurosporin and 300 microg/ml purified extract from Clematis mandshurica. Western blot assay, silencing 14-3-3 gene and immunoprecipitation were conducted. RESULTS: Clematis mandshurica prevented staurosporin-induced downregulation of several antiapoptotic bcl-2 family proteins Bcl-xL and Bcl-2, and staurosporin-induced upregulation of an apoptotic bcl-2 family protein Bax. Clematis mandshurica also prevented staurosporin-induced downregulation of a premitochondrial antiapoptotic protein 14-3-3. It is noticeable that siRNA to 14-3-3 abolished the prevention of caspase-3 activation by Clematis mandshurica. Furthermore viability assay corroborated that silencing of 14-3-3 gene abolished this apoptosis protection efficacy by Clematis mandshurica. Immunoprecipitation assay elucidated that Clematis mandshurica prevented the staurosporin-induced reduction of the interactions between 14-3-3 with phospho-ser112-Bad and Bcl-xL to phospho-ser155-Bad. CONCLUSIONS: Clematis mandshurica prevents staurosporin-induced apoptosis of rat chondrocytes via 14-3-3.     

Purified extract from Clematis mandshurica prevents adenoviral-TRAIL induced apoptosis on rat articular chondrocytes

Since TNF-related apoptosis inducing ligand (TRAIL) is one of several apoptotic stimuli on articular chondrocytes, the modulation of the mechanism mediated by TRAIL could be considered as a novel strategy for the treatment of osteoarthritis (OA). Previous studies demonstrated that Clematis mandshurica prevents staurosporin-induced apoptosis in articular chondrocytes. This study was undertaken to examine whether Clematis mandshurica could prevent TRAIL-induced apoptosis in articular chondrocytes. Our data show that Clematis mandshurica prevents adenoviral TRAIL (Ad-TRAIL)-induced apoptosis in primary cultured articular chondrocytes. Clematis mandshurica prevents Ad-TRAIL-induced down-regulation of 14-3-3 and phosphorylated Akt. In addition, Clematis mandshurica treatment prevents the Ad-TRAIL-induced reduction of the interactions between 14-3-3 with phospho-ser112-Bad and phospho-ser136-Bad, and BcL-xL with phospho-ser155-Bad. A better understanding of the mechanism underlying inhibition of apoptosis in OA chondrocytes by Clematis mandshurica might lead to the development of a new therapeutic strategy for OA.     

Effect of SKI 306X, a new herbal anti-arthritic agent, in patients with osteoarthritis of the knee: a double-blind placebo controlled study.

SKI 306X is a purified extract from a mixture of three oriental herbal medicines (Clematis mandshurica, Trichosanthes kirilowii and Prunella vulgaris) that have been widely used for the treatment of inflammatory diseases such as lymphadenitis and arthritis in far East Asia. A double-blind, controlled study was performed to evaluate the efficacy and safety of SKI 306X with placebo in 96 patients with classical osteoarthritis of the knee. Patients were randomized to four treatment groups: placebo, 200 mg, 400 mg and 600 mg of SKI 306X t.i.d.. Clinical efficacy and safety were evaluated for 4 weeks continuous treatment. SKI 306X demonstrated its clinical efficacy, as assessed by 100 mm visual analogue scale (VAS), Lequesne index and patients' and investigators opinion of the therapeutic effect compared with placebo (p<0.01). No significant adverse events were observed in patients treated with SKI 306X. This study demonstrated that SKI 306X, a new herbal anti-arthritic agent provided clinical efficacy in patients with osteoarthritis.     

A four-week, randomized, double-blind trial of the efficacy and safety of SKI306X: a herbal anti-arthritic agent versus diclofenac in osteoarthritis of the knee

The efficacy and safety of SKI306X, an herbal anti-arthritic agent, was compared with that of diclofenac sodium for the treatment of osteoarthritis of the knee. In a randomized, double-blind, active comparator-controlled trial, a total of 249 patients were randomly assigned to receive either 200 mg of SKI306X three times daily or 100 mg of diclofenac sustained release (SR) once daily. Clinical efficacy variables (visual analog scale, Lesquesne index and global satisfaction score) and adverse events were monitored at baseline and 2nd and 4th weeks of treatment. SKI306X demonstrated efficacy statistically comparable to that of diclofenac, as assessed by the VAS and patients' and investigators' global satisfaction score. Both treatments were well tolerated, however, the SKI306X treatment group experienced less heartburn (4.0% versus 13.7%, p = 0.015, chi-square test). In this four-week trial, SKI306X was well tolerated and demonstrated clinical efficacy comparable to that of diclofenac SR.     

桔梗皂苷D通过Bax/Bcl-2/Caspase-3信号通路抑制细胞凋亡保护急性肺损伤的机制研究＊

目的 探讨桔梗皂苷D对脂多糖诱导的大鼠急性肺损伤的保护机制。方法 35只雄性SPF级SD大鼠，随机分为假手术组、桔梗皂苷D对照组、模型组、桔梗皂苷D给药组和地塞米松组，每组7只。除假手术组和桔梗皂苷D对照组外，其余各组采用脂多糖诱导大鼠急性肺损伤模型。造模24 h后，牺牲大鼠并称体重及两肺重量，计算肺指数；脱氧核糖核苷酸末端转移酶介导的缺口末端标记（TUNEL）法检测肺组织细胞凋亡并计算凋亡指数（Apoptosis Index，AI）；透射电镜下观察大鼠肺组织超微结构的改变；蛋白免疫印迹法（Western blot）检测肺组织凋亡相关蛋白B细胞淋巴瘤/白血病-2（Bcl-2），Bcl-2相关X蛋白（Bax），半胱氨酸天冬氨酸蛋白酶-3（Caspase-3），多聚腺苷二磷酸核糖聚合酶1（PARP1）蛋白及活化的天冬氨酸蛋白水解酶-3（Cleaved Caspase-3），Cleaved PARP1的表达水平。结果 与假手术组比较，模型组大鼠肺指数显著升高（P < 0.01），肺组织细胞凋亡指数（AI）显著升高（P < 0.01），肺组织Bcl-2及Bcl-2/Bax蛋白表达显著下调（P < 0.01），Bax，Cleaved Caspase-3/Caspase-3，Cleaved PARP1/PARP1蛋白表达均显著升高（P < 0.01）；透射电镜下可见到凋亡小体，影响并改变了肺组织细胞超微结构；与模型组比较，桔梗皂苷D给药组及地塞米松组肺指数明显降低（P < 0.01），肺组织AI明显降低（P < 0.01），肺组织中Bcl-2及Bcl-2/Bax蛋白表达显著上调（P < 0.01），Bax，Cleaved Caspase-3/Caspase-3，Cleaved PARP1/PARP1蛋白表达均显著降低（P < 0.01）；透射电镜下，桔梗皂苷D给药组和地塞米松组肺组织细胞超微结构状态较好。结论 桔梗皂苷D对脂多糖诱导的大鼠急性肺损伤具有保护作用，其作用机制与抑制Bax/Bcl-2/Caspase-3信号通路，减轻肺组织细胞凋亡密切相关。     

冬凌草甲素诱导三阴乳腺癌MDA-MB-231细胞凋亡及对细胞内活性氧水平的影响

冬凌草甲素是从中药冬凌草Rabdosia rubescens中分离得到的一种贝壳杉烯二萜类的天然有机化合物,具有抗炎、抗菌、抗肿瘤等多种生物活性。该实验观察冬凌草甲素对三阴乳腺癌MDA-MB-231细胞凋亡的影响及其可能的作用机制。采用MTT法检测冬凌草甲素对MDA-MB-231细胞的增殖抑制作用,PI单染、Annexin V-FITC/PI双染流式细胞术分析冬凌草甲素对MDA-MB-231细胞凋亡的影响,活性氧(ROS)试剂盒检测细胞内ROS水平的变化,Western blot分析PARP,Bcl-2,caspase-3蛋白的表达情况。结果表明,冬凌草甲素对乳腺癌MDA-MB-231细胞具有明显的凋亡诱导作用,显著升高细胞内的ROS水平,下调抗凋亡蛋白Bcl-2的表达,并促进caspase-3及其底物PARP的切割。提示,冬凌草甲素诱导MDA-MB-231细胞凋亡的作用可能与升高细胞内ROS水平、下调Bcl-2的表达以及激活caspase-3相关。     

双氢青蒿素通过调节凋亡相关蛋白的表达及活性氧的产生而抑制胰腺癌JF-305细胞的增殖

探讨双氢青蒿素诱导人胰腺癌JF-305细胞凋亡作用及活性氧在双氢青蒿素诱导JF-305细胞凋亡中的作用。采用MTT法考察不同浓度双氢青蒿素对人胰腺癌JF-305细胞增殖的影响,流式细胞术检测细胞周期,Hochest 333258荧光染色法观察细胞凋亡形态,Annexin V荧光染色法检测JF-305细胞凋亡的变化,DCFH-DA检测凋亡过程中活性氧(ROS)的变化。Western blot检测细胞内Bax,Bcl-2,Cleaved caspase-3,Cleaved caspase-9和Cyto C蛋白表达的变化。与对照相比,双氢青蒿素作用JF-305细胞48 h,细胞增殖受到明显抑制(P0.05);细胞被阻滞于G2/M期;细胞出现核浓缩聚集、碎裂的凋亡形态,细胞凋亡比例升高(P0.05);DCFH-DA检测双氢青蒿素给药组细胞ROS明显升高(P0.05);Western blot结果显示,双氢青蒿素作用后细胞内Bcl-2蛋白表达下调,Bax蛋白表达上调,Bax/Bcl-2蛋白表达比例升高,Cleaved caspase-3,Cleaved caspase-9和Cyto C蛋白表达升高。双氢青蒿素能诱导JF-305细胞凋亡,其凋亡过程可能与ROS的生成增加相关。     

白藜芦醇联合姜黄素对SMMC-7721肝癌细胞作用

目的:观察白藜芦醇联合姜黄素对体外人肝癌细胞SMMC-7721增殖和凋亡的影响及相关信号通路.方法:不同浓度白藜芦醇、姜黄素及两药联合干预SMMC-7721细胞,MTT法检测细胞增殖,流式细胞术检测细胞凋亡、Hoechst 33258染色检测细胞凋亡形态变化,比色法检测半胱氨酸天冬氨酸蛋白酶(caspase)-3,caspase-8,caspase-9酶活性,Western blot法检测半胱氨酸天冬氨酸蛋白酶切割底物(PARP).结果:与对照组相比,白藜芦醇、姜黄素单独或联合作用SMMC-7721细胞均可抑制SMMC-7721细胞增殖,两药联合后抑制作用更显著.白藜芦醇、姜黄素联合较单独用药可增强SMMC-7721细胞凋亡,呈现凋亡形态改变,白藜芦醇、姜黄素及联合组细胞凋亡率分别为( 17.39±1.41)％,(14.96±2.23)％,(25.36±2.68)％;同时提高SMMC-7721细胞caspase-3,caspase-8及caspase-9活性,促使PARP蛋白剪辑.结论:白藜芦醇、姜黄素联合使用可增强对人肝癌细胞SMMC-7721的抗癌作用,并可能与caspase-8,caspase-9/caspase-3/PA RP信号通路介导细胞凋亡相关.     

东北铁线莲及其挥发油急性毒性试验研究

目的　试验观察东北铁线莲及其挥发油的急性毒性 ,为临床用药提供依据。方法　分别给予东北铁线莲及其挥发油灌胃 ,计算 10 0 %及 10 %小鼠死亡率 ;以 0 .8为系数给予同容量不同浓度的药物灌胃 ,观察其 72h内小鼠死亡率 ,计算LD50 。结果　小鼠出现少动、嗜睡呈渐进性加重 ,心率和呼吸减慢 ,肌肉松弛呈现麻醉状态 ,36h内全部死亡。Bliss法计算其LD50 ,分别为 5 1.85 g/kg、3.2 8mL/kg。 结论　东北铁线莲及其挥发油具有一定的毒性 ,应引起临床用药的注意     

白藜芦醇与紫杉醇联合用药对人喉癌Hep-2细胞凋亡机制的研究

喉癌是呼吸道肿瘤中最常见的恶性肿瘤之一,在呼吸道肿瘤中高居第二位。白藜芦醇(resveratrol,Res)是一种多酚类物质,可通过抑制细胞内核苷酸还原酶抑制肝癌细胞、胃癌细胞、胰腺癌细胞等肿瘤细胞生长。紫杉醇(taxol,Tax)是红豆杉属植物中一种次生代谢物,可抑制细胞内微管的解聚,对乳腺癌、宫颈癌、卵巢癌等肿瘤有良好的抗肿瘤活性。目前有关白藜芦醇联合紫杉醇用药针对人喉癌细胞株Hep-2的作用及其相关分子机制研究还鲜见报道。用白藜芦醇(Res)、紫杉醇(Tax)处理人喉癌细胞株Hep-2,采用CCK-8法检测2种药物对Hep-2细胞增殖的影响,AO/PI染色和JC-1检测Hep-2细胞凋亡,实时定量PCR检测Bax,Bcl-2,PARP,TRIB3,XIAP基因的表达,荧光定量法检测caspase-3,caspase-8活性。结果表明,与Tax,Res单独用药相比,联合组显著增强对Hep-2细胞的抑制作用,且明显减少Tax的用药剂量,增加Bax,PARP,TRIB3的表达,降低Bcl-2,XIAP的表达,促进caspase-3,caspase-8活性。这表明Res,Tax以及其联合药物通过线粒体途径诱导喉癌细胞Hep-2的细胞凋亡。这为进一步研究Res,Tax联合用药治疗喉癌奠定理论基础,且扩大Res,Tax联合用药范围。     

Dehydrocorydaline inhibits breast cancer cells proliferation by inducing apoptosis in MCF-7 cells

Dehydrocorydaline is an alkaloid isolated from traditional Chinese herb Corydalis yanhusuo W.T. Wang. We discovered that it possessed anti-tumor potential during screening of anti-tumor natural products from Chinese medicine. In this study, its anti-tumor potential was investigated with breast cancer line cells MCF-7 in vitro. The anti-proliferative effect of dehydrocorydaline was determined by MTT assay and the mitochondrial membrane potential (Δ Ψ m) was monitored by JC-1 staining. DNA fragments were visualized by Hoechst 33342 staining and DNA ladder assay. Apoptotic related protein expressions were measured by Western blotting. Dehydrocorydaline significantly inhibited MCF-7 cell proliferation in a dose- dependent manner, which could be reversed by a caspase-8 inhibitor, Z-IETD-FMK. Dehydrocorydaline increased DNA fragments without affecting ΔΨm. Western blotting assay showed that dehydrocorydaline dose-dependently increased Bax protein expression and decreased Bcl-2 protein expression. Furthermore, dehydrocorydaline induced activation of caspase-7,-8 and the cleavage of PARP without affecting caspase-9. These results showed that dehydrocorydaline inhibits MCF-7 cell proliferation by inducing apoptosis mediated by regulating Bax/Bcl-2, activating caspases as well as cleaving PARP.     

莪术醇对肺癌A549细胞凋亡诱导因子、 聚ADP核糖聚合酶及Caspase-3表达的影响

目的:观察莪术醇干预后,体外培养A549细胞凋亡诱导因子(apoptosis induce factor,AIF)和聚ADP核糖聚合酶[poly(ADP-ribose)polymerase,PARP]的表达情况,探讨莪术醇对非半胱天冬酶(caspase)依赖细胞凋亡的分子机制。方法:以不同质量浓度的莪术醇(12.5,25,50,100 mg.L-1)及阴性组处理肺癌细胞,药物作用48 h后提取各组蛋白;采用Westernblotting法分别检测各组AIF,PARP,caspase-3蛋白表达,并进行统计学分析。结果:经莪术醇处理后,阴性组的A549细胞的PARP相对蛋白表达量为0.545 3,AIF的相对蛋白表达量为0.358 6,而100 mg.L-1加药组的相对蛋白表达量分别为1.661 3和2.212 4,蛋白表达均随药物浓度的增加而增多,药物组与阴性组相比差异极显著(P<0.01),而caspase-3的前体(32×103)表达受药物影响较小,其激活体(17×103)基本不表达。结论:莪术醇可能主要是通过上调PARP蛋白的表达,进而将AIF转位到细胞核而引起凋亡的非依赖caspase途径来介导肺癌A549细胞的凋亡。     

薯蓣皂苷的次皂苷元B（DRG）体外诱导人大肠癌HCT-15细胞凋亡的机制研究

 目的 探讨中药单体薯蓣皂苷的次皂苷元B(DRG)体外诱导HCT-15细胞凋亡的分子作用机制。方法 采用Western blotting、体外Bcl-xL蛋白竞争结合检测实验及逆转录PCR（RT-PCR）对DRG诱导细胞凋亡的机制进行了研究。结果 在HCT-15细胞中,DRG促发了线粒体调控的凋亡途径,细胞色素c呈时效性地从线粒体中释放到胞质中,同时Bax与Bcl-2蛋白表达的相对比例上调,caspase-9、caspase-3和PARP等被剪切成具有活性的片段,但是caspase-7却未见剪切,同时还不影响P53和Bcl-xL的表达;而与死亡受体途径相关的FADD表达无明显变化,caspase-8酶原也未见剪切;另外,DRG也不抑制BH3短肽与Bcl-xL的结合;RT-PCR检测结果表明,DRG诱导HCT-15细胞凋亡相关基因Bcl-2和Bax的mRNA水平的改变,进而导致Bcl-2蛋白表达水平下降,而Bax蛋白表达水平则明显增加,说明DRG诱发的细胞凋亡中涉及到Bcl-2和Bax基因水平的变化。结论 DRG诱发HCT-15细胞凋亡的分子机制在于从基因水平影响Bax和Bcl-2靶基因的转录表达,上调Bax/Bcl-2蛋白表达水平比例,并最终通过激活经典的线粒体途径而不是死亡受体途径来发挥其HCT-15细胞凋亡诱导作用,且对P53呈非依赖型。     

化痰除湿祛瘀剂膝痹康对膝骨关节炎患者软骨细胞凋亡调控基因表达的影响

目的研究化痰除湿祛瘀剂膝痹康对人骨关节炎(osteoarthritis,OA)软骨细胞调控基因表达的影响。方法取全膝关节置换手术膝骨关节炎患者的软骨组织,采用酶消化培养法培养人软骨细胞,采用甲苯胺蓝染色鉴定细胞来源。将软骨细胞分为对照组、膝痹康0.016、0.08、0.4、2.0、10.0 mg/m L组,培养24 h后,应用甲基噻唑基四唑(MTT)法检测各组细胞的增殖情况。根据增殖结果将软骨细胞分为对照组、膝痹康低、中、高剂量组(0.05、0.1、2.0 mg/m L),用TUNEL法检测各组细胞凋亡情况,以实时荧光定量PCR(RT-PCR)法检测各组细胞Bcl-2、Bcl-2同源水溶性相关蛋白X(Bax)及p53 mRNA表达。结果本研究成功建立了人骨关节炎软骨细胞有限细胞系,细胞生长状态良好;甲苯胺蓝染色证明所培养的细胞为来自中胚层的软骨细胞。膝痹康在0.016~10.0 mg/m L范围内对OA软骨细胞波长=450 nm处24 h的光密度(OD)有影响。与对照组相比,膝痹康低剂量组细胞凋亡率无明显变化(P0.05),膝痹康中、高剂量组下降(P0.05,P0.01)。膝痹康低、中、高剂量组间比较显示,两两比较差异均有统计学意义(P0.05)。与对照组相比,膝痹康低剂量组Bcl-2、Bax及p53 mRNA相对表达量无明显变化(P0.05),膝痹康中、高剂量组Bcl-2 mRNA表达量明显上调(P0.05),Bax及p53 mRNA表达量明显下调(P0.05,P0.01);与膝痹康低剂量组相比,膝痹康中、高剂量组Bcl-2 mRNA表达量明显上调(P0.05),Bax及p53 mRNA表达量明显下调(P0.05,P0.01);与膝痹康中剂量组相比,膝痹康高剂量组Bax mRNA表达量明显下调(P0.05)。结论化痰除湿祛瘀剂膝痹康调控细胞凋亡基因的表达,抑制软骨细胞过度凋亡,这可能是抑制软骨破坏的重要机制之一。     

熊果酸对乳腺癌细胞caspase-3和PARP表达的影响

目的:探讨三萜类中药成分熊果酸(UA)诱导乳腺癌细胞MCF-7的凋亡作用,并通过分析UA作用后MCF-7细胞的caspase-3和多聚ADP核糖多聚糖(PARP)蛋白表达的变化,探讨其诱导MCF-7细胞凋亡的分子机制。方法:采用细胞培养技术,用不同浓度的药物在一定的时间内处理细胞株,采用MTT法、活细胞原位光镜和荧光染色技术、流式细胞技术(FCM)、荧光免疫组织化学技术,图象分析技术,研究UA对caspase-3和PARP蛋白表达的影响,诱导细胞凋亡的作用。结果:UA剂量依赖性的抑制MCF-7细胞增殖,半数生长抑制剂量(IC₅₀)为(22.6±3.0)μmol.L^-1,诱导caspase-3和PARP表达增加,使细胞呈现典型的凋亡形态学特征,核质浓集,有凋亡小体。结论:UA诱导MCF-7细胞凋亡,其机制涉及到caspase-3和PARP依赖性凋亡调节信号通路。     

Xanthohumol induces apoptosis in human malignant glioblastoma cells by increasing reactive oxygen species and activating MAPK pathways

The effect of the biologically active prenylated chalcone and potential anticancer agent xanthohumol (1) has been investigated on apoptosis of the T98G human malignant glioblastoma cell line. Compound 1 decreased the viability of T98G cells by induction of apoptosis in a time- and concentration-dependent manner. Apoptosis induced by 1 was associated with activation of caspase-3, caspase-9, and PARP cleavage and was mediated by the mitochondrial pathway, as exemplified by mitochondrial depolarization, cytochrome c release, and downregulation of the antiapoptotic Bcl-2 protein. Xanthohumol induced intracellular reactive oxygen species (ROS), an effect that was reduced by pretreatment with the antioxidant N-acetyl-L-cysteine (NAC). Intracellular ROS production appeared essential for the activation of the mitochondrial pathway and induction of apoptosis after exposure to 1. Oxidative stress due to treatment with 1 was associated with MAPK activation, as determined by ERK1/2 and p38 phosphorylation. Phosphorylation of ERK1/2 and p38 was attenuated using NAC to inhibit ROS production. After treatment with 1, ROS provided a specific environment that resulted in MAPK-induced cell death, with this effect reduced by the ERK1/2 specific inhibitor PD98059 and partially inhibited by the p38 inhibitor SB203580. These findings suggest that xanthohumol (1) is a potential chemotherapeutic agent for the treatment of glioblastoma multiforme.     

龙葵碱对HepG2细胞内caspase-3及Bcl-2蛋白含量的影响

目的：观察龙葵碱对HepG2细胞内caspase-3及Bcl-2蛋白含量的影响，阐明龙葵碱诱导肿瘤细胞凋亡的作用机制、方法：采用激光共聚焦扫描显微术和Western blot法检测caspase-3和Bcl-蛋白含量，并对二者在细胞内的位置进行定位．结果：龙葵碱能够显著升高HepG2细胞内caspase-3蛋白含量，降低Bcl-2的含量，并且均具有剂量依赖性，Bcl-2蛋白和caspase-3蛋白均在细胞浆内呈不均匀分布，在细胞核中无分布，龙葵碱对二者的分布没有影响.结论：龙葵碱通过抑制Bcl-2的活性，激活easpase-3蛋白，诱导细胞凋亡的发生.     

大黄苷元联合尿激酶动脉溶栓对血栓栓塞性脑缺血大鼠神经细胞凋亡的影响

目的:探讨大黄苷元联合不同时间窗溶栓治疗对脑缺血大鼠神经细胞凋亡的阻抑作用及其对相关调控基因蛋白表达的影响。方法:大鼠随机分为假手术组、模型组、尿激酶溶栓组(简称溶栓组)、大黄苷元组和联合组(大黄苷元+尿激酶组)。大鼠自体血栓结合线栓阻塞大脑中动脉制备血栓栓塞性脑缺血动物模型。大鼠分别于缺血后3,6,9 h经导管由颈内动脉用尿激酶进行溶栓。动脉给尿激酶后24 h,观察大鼠脑组织病理改变;免疫组织化学法检测神经细胞凋亡和凋亡相关基因蛋白Bax,caspase-3和Bcl-2表达。结果:各模型组大鼠病理改变明显,TUNEL细胞增多、Bax和caspase-3表达增强、Bcl-2表达下调;各用药组较模型组TUNEL细胞减少,6 h和9 h组Bax和caspase-3表达减弱、6 h组Bcl-2表达上调;各组9 h分别较其3h的TUNE细胞数增加、Bax增强、Bcl-2减弱;联合组分别较单一用药各时间组TUNEL细胞数减少、6 h和9 h组Bax及caspase-3表达减弱、Bcl-2表达上调。结论:脑缺血可使促凋亡基因Bax表达上调和抑凋亡基因Bcl-2下调,引起神经细胞凋亡,且随缺血时间延长而明显。大黄苷元及尿激酶溶栓可下调Bax,caspase-3,上调Bcl-2表达,对脑缺血神经细胞凋亡有阻抑作用,以二者联合用药的效果尤为理想。     

七叶皂苷钠通过抑制AKT,ERK上游信号SRC活性诱导人乳腺癌MCF-7细胞凋亡

探讨七叶皂苷钠对乳腺癌MCF-7细胞的凋亡诱导作用及其可能的作用机制。运用MTT法检测七叶皂苷钠对MCF-7细胞的增殖抑制作用;倒置显微镜观察细胞形态学变化;DAPI染色后在荧光显微镜下检测细胞核变化;采用Annexin V-FITC/PI流式细胞术检测细胞凋亡率;采用Western blotting检测凋亡相关蛋白(PARP,cleaved caspase-8,pro-caspase-3)和细胞存活相关信号分子(AKT,ERK)及其共同上游激酶SRC的磷酸化变化情况。结果显示,不同浓度七叶皂苷钠作用于乳腺癌MCF-7细胞后,以剂量依赖方式抑制MCF-7细胞增殖;诱导细胞凋亡(典型的凋亡形态学变化、细胞核改变和细胞凋亡率显著增加);细胞凋亡相关蛋白PARP切割增加,cleaved caspase-8表达增加,pro-caspase-3表达减少进一步验证了七叶皂苷钠的凋亡诱导作用;七叶皂苷钠显著抑制细胞存活相关信号分子(AKT,ERK)的磷酸化,其共同上游激酶SRC的活化亦显著下降。结果表明,七叶皂苷钠通过抑制SRC的活化,阻断信号向下游信号分子AKT,ERK的传递,抑制乳腺癌细胞MCF-7增殖,诱导细胞凋亡。     

金丝桃苷对叠氮钠诱导PC12细胞凋亡的保护作用(英文)

目的:研究金丝桃苷对叠氮钠诱导的PC12细胞凋亡的保护作用。方法:将PC12细胞与不同浓度金丝桃苷共同孵育4h后,加入20mmol·L-1的叠氮钠继续孵育3～24h,观察金丝桃苷的保护作用。采用MTT、Hoechst33342分别检测细胞存活率和细胞形态变化。以Ac-DEVD-AMC为底物检测caspase-3活性,CM-H2DCFDA法用于测定ROS水平。Western blotting用于分析Bcl-2和Bax表达水平。结果:金丝桃苷在0.01,0.1及1μmol·L-1浓度时,可显著提高叠氮钠作用后PC12细胞的存活率,抑制细胞凋亡,减少细胞内活性氧自由基生成和caspase-3活性,提高抗凋亡蛋白Bcl-2表达,降低促凋亡因子Bax表达。同时结果显示caspase-3抑制剂呈时间依赖性地减少细胞内活性氧自由基含量。结论:金丝桃苷对叠氮钠诱导的PC12细胞凋亡具有保护作用,活性氧自由基生成与凋亡进程中caspase-3活性密切相关。