热休克蛋白90对血小板源衍生因子诱导的大鼠主动脉平滑肌细胞增殖的影响

目的:研究热休克蛋白90(HSP90)对血小板衍生因子(Platelet derived growth factor,PDGF)诱导的大鼠主动脉平滑肌细胞增殖的影响。方法:采用胶原酶消化法原代培养大鼠胸主动脉平滑肌细胞,应用脂质体细胞转染siRNA的方法抑制HSP90的表达,定量PCR和western blot的方法检测抑制效率。利用PDGF-bb诱导刺激平滑肌细胞增殖,CCK8法检测细胞增殖能力的变化,流式细胞术检测细胞生长周期的改变。结果:平滑肌细胞中转染HSP90的siRNA后,HSP90的mRNA和蛋白水平明显降低,分别为对照组的65.3%和57.6%(P0.05);PDGF-bb刺激明显促进平滑肌细胞生长,而降低HSP90水平显著影响PDGF-bb诱导的细胞增殖(P0.05);流式细胞术检测发现降低HSP90水平引起平滑肌细胞生长停滞,分布在细胞周期G1期的细胞比例明显增多(P0.05)。结论:HSP90通过调控平滑肌细胞的生长周期参与调节细胞增殖过程。

Effect of Heat Shock Protein 90 on Proliferation of Rat Aortic Smooth Muscle Cells Induced by Platelet Derived Growth Factor

Objective:To investigate the effect of heat shock protein 90 (HSP90) on proliferation of rat aortic smooth muscle cells induced by PDGF (Platelet derived growth factor).Methods:The primary aortic smooth muscle cells were cultured from thoracic aortas by collagenase digestion methods. The expression of HSP90 was intervened by liposomes with siRNA, and determined by real-time PCR and western blot. Proliferation of smooth muscle cells were stimulated PDGF-bb, and were detected by CCK8 assay. The cell cycle of smooth muscle cells were determined by flow cytometry.Results:Smooth muscle cells transfected with siRNA 24 h later, mRNA and protein levels of HSP90 significantly decreased by 65.3% and 57.6% respectively, compared with control groups. The proliferation of fibroblasts were markedly promoted by PDGF-bb, but HSP90 siRNA suppressed the cell proliferation. Flow cytometry assay showed that smooth muscle cells transfected with HSP90 siRNA were found arrest in the G1 phase of the cell cycle.Conclusion:HSP90 is involved in the proliferation of smooth muscle cells by regulating cell cycle.