Effect of Triptolide on Proliferation of Rat Vascular Smooth Muscle Cells

Objective To explore the effects and mechanism of Triptolide on the proliferation of cultured vascular smooth muscle cells (VSMCs). Methods Aortic smooth muscle cells of rats were cultured and characterized in vitro. Using rapamycin as positive control, we used cell counting to investigate the effects of Triptolide and rapamycin on the VSMCs. Flow cytometry was used to study the influence of Triptolide and rapamycin on the VSMCs cell cycle. The effects of Triptolide on c-fos mRNA expression were measured by RT-PCR. Results Triptolide and rapamycin inhibited proliferation of VSMCs induced by blocking cell cycle progress from G 0/G 1phase to S phase. It was founded that Triptolide inhibited c-fos mRNA expression in a concentration dependent maner. Conclusion Down-regulation of proto-oncogen c-fos mRNA expression by Triptolide may be one of the mechanisms with which Triptolide displays its inhibitory effect on VSMCs.