Effects of active components extracted from Qixue Bingzhi Recipe on proliferation of vascular smooth muscle cells and expressions of platelet-derived growth factor and its receptor genes

OBJECTIVE: To observe the effects of paeoniflorin and total flavones extracted from Qixue Bingzhi Recipe on proliferation of vascular smooth muscle cells (VSMCs) cultured in endothelial cell conditioned medium (EC-CM) induced by oxidized low-density lipoprotein (ox-LDL) and the expressions of platelet-derived growth factor and its receptor genes. METHODS: The VSMCs were cultured in normal culture medium, EC-CM, simvastatin-medicated EC-CM, paeoniflorin and total flavones (low, medium and high dose) -medicated EC-CM respectively. The growth activity of VSMCs was assessed by thiazolyl blue tetrazolium bromide (MTT) assay. The expressions of platelet-derived growth factor (PDGF)-BB and platelet-derived growth factor receptor-alpha (PDGFR-alpha) mRNAs were detected by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The growth activity of VSMCs cultured in the EC-CM induced by ox-LDL was significantly higher than that in the normal culture medium (P<0.01), and the expressions of PDGF-BB and PDGFR-alpha mRNAs were obviously increased as compared with those in the normal culture medium. The growth activity of VSMCs cultured in each paeoniflorin and total flavones-medicated EC-CM was significantly lower than that in the EC-CM (P<0.01), and the expressions of PDGF-BB and PDGFR-alpha mRNAs were obviously decreased as compared with those in the EC-CM. CONCLUSION: The paeoniflorin and total flavones extracted from Qixue Bingzhi Recipe may be beneficial to the prevention and treatment of arteriosclerosis, and this efficacy may be correlated with down-regulating the expressions of PDGF-BB and PDGFR-alpha mRNAs which are related to the proliferation of VSMCs cultured in EC-CM induced by ox-LDL.