论文部分内容阅读
目的探讨过氧化物酶体增殖物活化受体γ(PPARγ)激动剂罗格列酮对醛固酮诱导的肾小球系膜细胞(MC)增殖的影响及其作用机制。方法体外培养小鼠MC,应用醛固酮刺激或应用罗格列酮预处理后再应用醛固酮刺激,采用3H-胸腺嘧啶(3H-TdR)掺入法和细胞计数测定MC增殖;应用Western blot检测细胞周期素cyclin D1、cyclin A表达及磷酸肌醇-3激酶/蛋白激酶B(PI3K/Akt)磷酸化。结果1.MC应用100 nmol/L醛固酮刺激后,其3H-TdR掺入量及细胞数分别是基础状态下的2.46倍和2.14倍;PPARγ受体激动剂罗格列酮可呈剂量依赖性抑制醛固酮诱导的MC增殖,抑制率可达80%以上。2.醛固酮刺激12 h后,MCcyclin D1和cyclin A表达。罗格列酮可呈剂量依赖性抑制醛固酮诱导的MC cyclin D1和cyclin A表达。3.醛固酮呈剂量依赖性促进MC PI3K/Akt信号通路活化,100 nmol/L醛固酮刺激60 min,磷酸化PI3K和Akt表达是对照组的3倍以上。4.PI3K抑制剂LY294002或Akt抑制剂显著抑制醛固酮诱导的细胞周期蛋白表达,其抑制率达80%以上。5.罗格列酮显著抑制醛固酮诱导的PI3K/Akt信号通路活化,10μmol/L罗格列酮几乎完全阻断醛固酮诱导的PI3K和Akt活化。结论罗格列酮通过阻断PI3K/Akt信号通路活化而抑制醛固酮诱导的MC增殖。
Objective To investigate the effect of peroxisome proliferator-activated receptor γ (PPARγ) agonist rosiglitazone on aldosterone-induced proliferation of mesangial cells (MC) and its mechanism. Methods Mice MC were cultured in vitro and were stimulated with aldosterone or rosiglitazone followed by aldosterone stimulation. The proliferation of MC was detected by 3H-thymidine incorporation and cell counting. The cell cycle Cyclin D1, cyclin A expression and phosphoinositide 3-kinase / protein kinase B (PI3K / Akt) phosphorylation. The results showed that 3H-TdR incorporation and cell number were 2.46-fold and 2.14-fold, respectively, in the MCs treated with 100 nmol / L aldosterone. Rosiglitazone, a PPARγ receptor agonist, showed a dose-dependent inhibition Aldosterone-induced MC proliferation, inhibition rate of up to 80%. The expression of MCcyclin D1 and cyclin A were detected after aldosterone stimulation for 12 h. Rosiglitazone inhibited aldosterone-induced MC cyclin D1 and cyclin A expression in a dose-dependent manner. Aldosterone promoted MC PI3K / Akt signaling pathway in a dose-dependent manner, and the phosphorylation of PI3K and Akt was more than 3 times higher than that of the control group after 100 nmol / L aldosterone stimulation for 60 min. PI3K inhibitor LY294002 or Akt inhibitor significantly inhibited aldosterone-induced cyclin expression, the inhibition rate of more than 80%. Rosiglitazone significantly inhibited aldosterone-induced PI3K / Akt signaling pathway activation, 10μmol / L rosiglitazone almost completely blocked aldosterone-induced PI3K and Akt activation. Conclusion Rosiglitazone inhibits aldosterone-induced MC proliferation by blocking the activation of the PI3K / Akt signaling pathway.