枸杞多糖对人肺腺癌 A549细胞增殖和凋亡的影响

目的探讨枸杞多糖(LBP)对体外培养的人肺腺癌细胞 A549的增殖抑制作用及其可能的作用机制.方法用不同浓度的LBP处理 A549细胞,MTT法检测24、48、72h时间点 LBP对 A549细胞的生长抑制率,实验设为对照组和实验组(1/2IC50作用48小时),MTT法绘制生长曲线、细胞计数计算倍增时间、流式细胞仪检测凋亡率及其细胞周期、RT PCR检测 SurvivinmRNA的变化、Westernblot检测 CyclinB1蛋白的变化,transwell体外侵袭实验观察药物对细胞体外侵袭的影响.结果 MTT显示不同浓度的LBP均能明显抑制 A549细胞的增殖且成剂量 效应关系,实验组细胞的倍增时间、凋亡率与对照组相比,均有统计学意义(P<0.05);LBP使细胞阻滞在 G2期,SurvivinmRNA表达和 CyclinB1蛋白的表达均降低,与对照组相比差异有显著性(P<0.05).结论 LBP可抑制 A549细胞的增殖,其机理可能与 LBP使 SurvivinmRNA表达下降引起细胞凋亡及 CyclinB1蛋白的表达降低造成细胞周期阻滞及抑制细胞的侵袭能力有关     

TRAIL induces proliferation of human glioma cells by c-FLIPL-mediated activation of ERK1/2

TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in TRAIL-sensitive human malignant glioma cells. We show for the first time that TRAIL stimulates cell growth in TRAIL-resistant glioma cells. TRAIL-induced cell growth in resistant cells occurred through increased cell cycle progression as determined by flow cytometry and Western blot analysis of retinoblastoma protein phosphorylation. Western blot analysis of TRAIL-treated resistant cells revealed phosphorylation of ERK1/2 proteins and in vitro kinase analysis confirmed the activation of the ERK1/2 kinases. Inhibition of MEK1 eliminated both TRAIL-induced ERK1/2 activation and cell proliferation. In addition, siRNA inhibition of c-FLIP expression eliminates TRAIL-induced ERK1/2 activation and proliferation. Furthermore, overexpression of c-FLIP_L potentiates TRAIL-induced ERK1/2 activation and proliferation of resistant glioma cells. Our results have shown for the first time that TRAIL-induced ERK1/2 activation and proliferation of TRAIL-resistant human glioma cells is dependent upon the expression of the long form of the caspase-8 inhibitor c-FLIP_L. Received 2 November 2007; received after revision 14 December 2007; accepted 21 December 2007     

Polycystic kidney diseases: From molecular discoveries to targeted therapeutic strategies

Polycystic kidney diseases (PKDs) represent a large group of progressive renal disorders characterized by the development of renal cysts leading to end-stage renal disease. Enormous strides have been made in understanding the pathogenesis of PKDs and the development of new therapies. Studies of autosomal dominant and recessive polycystic kidney diseases converge on molecular mechanisms of cystogenesis, including ciliary abnormalities and intracellular calcium dysregulation, ultimately leading to increased proliferation, apoptosis and dedifferentiation. Here we review the pathobiology of PKD, highlighting recent progress in elucidating common molecular pathways of cystogenesis. We discuss available models and challenges for therapeutic discovery as well as summarize the results from preclinical experimental treatments targeting key disease-specific pathways. Received 8 August 2007; received after revision 19 September 2007; accepted 2 October 2007     

Pleiotropic effects of sonic hedgehog on muscle satellite cells

Muscle satellite cells are believed to form a stable, self-renewing pool of stem cells in adult muscle where they function in tissue growth and repair. A regulatory disruption of growth and differentiation of these cells is assumed to result in tumor formation. Here we provide for the first time evidence that sonic hedgehog (Shh) regulates the cell fate of adult muscle satellite cells in mammals. Shh promotes cell division of satellite cells (and of the related model C2C12 cells) and prevents their differentiation into multinucleated myotubes. In addition, Shh inhibits caspase-3 activation and apoptosis induced by serum deprivation. These effects of Shh are reversed by simultaneous administration of cyclopamine, a specific inhibitor of the Shh pathway. Taken together, Shh acts as a proliferation and survival factor of satellite cells in the adult muscle. Our results support the hypothesis of the rhabdomyosarcoma origin from satellite cells and suggest a role for Shh in this process.Received 23 February 2005; received after revision 2 May 2005; accepted 9 June 2005     

卡介苗胞壁脂聚糖诱导鼠巨噬细胞增殖后凋亡的研究

研究卡介苗胞壁脂聚糖提取物对小鼠巨噬细胞株Ana-1的影响.采用超声波破碎细菌、Triton X-114相分离和酒精沉淀等方法分离得到卡介苗胞壁总脂聚糖的提取物;采用苯酚-硫酸法检测提取物中多糖含量,用不同浓度梯度的提取物刺激后,采用XTT法检测24h后Ana-1细胞增殖的情况,选择40×10-6g/mL胞壁脂聚糖刺激细胞48h,72h后,用流式细胞仪检测Ana-1细胞凋亡的结果.卡介苗胞壁脂聚糖提取物对Ana-1细胞的增殖活力有促进作用,而继续作用后诱导了细胞凋亡.卡介苗胞壁脂聚糖促进了鼠巨噬细胞的增殖,可能引起巨噬细胞的细胞因子的分泌而诱导了细胞凋亡,有较强的免疫活性.     

中国鲎鲎素对人胃癌BGC—823细胞增殖的抑制作用

应用从中国鲎血细胞中提取的鲎素处理人胃癌BGC－823细胞,研究海洋生物活性物质的抗肿瘤作用。实验结果显示,经2．0μg/ml鲎素处理的BGC－823细胞生长缓慢,倍增时间延长,细胞集落形成能力减弱,细胞生长抑制率达62．67％,细胞分裂指数下降40．91％,处理后细胞碱性磷酸酶细胞化学反应减弱、分布改变、碱性磷酸酶和乳酸脱氢酶活力分别下降40．59％和76．05％。结果表明,鲎素能有效地抑制胃癌细胞的增活动,具有与癌细胞诱导分化物相似的抗肿瘤效果。     

清热解毒药对血管平滑肌细胞增殖、细胞周期的影响

目的 :观察清热解毒药双花、公英、虎杖、连翘对血管平滑肌细胞生长、贴壁和增殖抑制作用 ,并从对细胞周期的影响角度分析它们的作用机制。方法 :采用细胞计数、MTT法和流式细胞技术。结果 :双花、公英、虎杖、连翘对h PDGF B/B刺激下的平滑肌细胞生长和贴壁均有抑制作用。对平滑肌细胞增殖抑制率分别达 9.2 6%～ 77.35% ,7.78%～ 62 .65% ,5.88%～ 47.81 % ,3.98%～ 33.35% ,其增殖抑制作用呈量效时效关系。通过对细胞周期分析知道 ,双花、公英、虎杖均可以减少 S期 ,增加 G0 /G1期细胞数目。结论 :清热解毒药双花、公英、虎杖、连翘对平滑肌细胞生长及增殖有抑制作用 ,其作用机制可能是通过抑制 DNA合成 ,减少进入 S期细胞数目 ,使细胞增殖停留在 G0 /G1期来实现的     

石见穿萃取物对体外培养成骨细胞活性的影响

石见穿以95%乙醇抽提得总提物.分别用不同试剂萃取总提物,获得其石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物以及其水溶性成分.以体外培养成骨细胞MC3T3-E1为模型,用cck-8法测定细胞增殖,碱性磷酸酶(ALP)试剂盒法测定了上述不同萃取物对成骨细胞增殖和分化的影响.结果表明:总提物在浓度10～-3、10-4、10-...     

佛手挥发油对B16细胞增殖及其酪氨酸酶活性的影响

为检测佛手挥发油对B16黑色素瘤细胞增殖及其酪氨酸酶活性的影响,采用台盼蓝排斥法测定了细胞存活率、瑞-姬氏混染法观察了细胞形态变化、吖啶橙/溴化乙锭染色法检测了细胞的凋亡与坏死,用酶学方法测定了细胞中酪氨酸酶活性.结果表明:佛手挥发油对B16黑色素瘤细胞增殖具有显著的抑制作用,呈剂量依赖性;62.50,125.00和250.00μg.mL-1佛手挥发油处理细胞6 h后,细胞核染色质凝聚于核膜内侧,呈固缩状或圆珠状,表现为典型的细胞凋亡特征;500.00μg.mL-1佛手挥发油处理细胞后,细胞膜破裂,出现细胞碎片,说明细胞已经坏死.酪氨酸酶活性检测结果显示:佛手挥发油对B16黑色素瘤细胞酪氨酸酶活性具有明显的抑制作用,且呈剂量依赖性.     

维生素E和硒对正常及其恶性细胞增殖的联合作用

为进一步评价补充维生素Ｅ和硒的安全性，本文以正常仓鼠幼肾成纤维细细胞株及其多瘤病毒转化的恶性细胞株为对象，探讨了不同浓度的维生素Ｅ和硒对该对细胞增殖情况的单独和联合作用。结果显示：７μｍｏｌ／Ｌ的维生素Ｅ使ＢＨＫ－２１／ｃ１３和ＢＨＫ－２１／ＰｙＹ细胞株在９６ｈ的细胞计数分别增加１１％和１６％；０．１μｍｏｌ／Ｌ的亚硒酸钠对上述二株细胞的增殖无影响；同时补充以上相同浓度的维生素Ｅ和亚硒酸钠，９６ｈ