三七总皂甙对血管平滑肌细胞增殖及c-myc基因表达的影响

目的探讨三七总皂甙对血小板源生长因子刺激的血管平滑肌细胞增殖的影响及其可能机制。方法运用血小板源生长因子刺激兔体外血管平滑肌细胞增殖模型,通过四甲基偶氮唑盐比色法、流式细胞术及免疫细胞化学法观察三七总皂甙对其增殖活性、细胞周期及c-myc蛋白表达的影响。结果血小板源生长因子显著刺激血管平滑肌细胞增殖,三七总皂甙呈浓度依赖性抑制血管平滑肌细胞增殖,对血小板源生长因子诱导的血管平滑肌细胞增殖亦具有显著抑制作用;三七总皂甙作用下血管平滑肌细胞处于G1/G0期的细胞数增多,而G2/S期的细胞数显著减少,c-myc蛋白的表达亦降低。结论三七总皂甙对基础状态下及血小板源生长因子诱导的血管平滑肌细胞增殖均具有显著抑制作用,部分机制与其阻滞血管平滑肌细胞G1/G0期向S期转化以及下调c-myc基因表达有关。

Effects of Total Spaonins of Panax Notoginseng on c-myc Gene Expression and Proliferation of Cultured Vascular Smooth Muscle Cells

Aim To explore the effect of total spaonins of panax notoginseng(tPNS) on the proliferation of vascular smooth muscle cell(VSMC) induced by platelet derived growth factor(PDGF) and the possible underlying mechanisms. Methods Cell proliferating model of rabbit aorta VSMC induced by PDGF-BB was established.The proliferative activity of VSMC with tPNS was analyzed by MTT method; the effect of tPNS on cell cycle of VSMC was observed by flow cytomytry technique;the effect of tPNS on c-myc gene expression in VSMC was observed by immunocytochemical method. Results MTT metabolism of VSMC in the basic and PDGF-BB stimulated situation was inhibited by tPNS,and the cells numbers of G_0/G_1 phase were increased and that of G_2/S phase were decreased markedly.At the same time,highly expression of c-myc gene protein stimulated by PDGF could be inhibited by tPNS significantly. Conclusions tPNS can inhibit the proliferation of VSMC induced by PDGF significantly,at least in part by preventing VSMC from G_0/G_1 phase entering S phase and downgulating the expression of oncogene c-myc protein.