硒对动脉平滑肌细胞增殖作用机制的探讨

Investigaitgating of the mechanism of effect of selenium on proliferation of rabbit VSMCs

目的:探讨硒(Se)拮抗同型半胱氨酸(hemocysteine,HCY)刺激大兔动脉平滑肌细胞(VSMCs)增殖的作用机制。方法:首先将兔胸主动脉VSMCs进行培养,然后加入250、500、1000、2000、4000μmol/L不同浓度的D,L-HCY,经MTT方法的检测,选择VSMCs增殖率最适宜的浓度;在加入最适宜1000μmol/LHCY的VSMCs中再分别加入50、100、200μmol/L不同浓度的硒代蛋氨酸(Se-Met)。经姬姆萨染色,通过流式细胞技术观察细胞周期,提取细胞基因组DNA进行琼脂糖凝胶电泳及谷胱苷肽过氧化物酶(GSH-Px)活性的测定。结果:不同浓度的Se-Met使HCY作用的VSMCs生长明显受到抑制(P<0.05)。但姬姆萨染色没有发现凋亡小体。流式细胞术检测到S期细胞显著减少(P<0.05),未检测到凋亡峰。基因组DNA经琼脂糖电泳也没有发现细胞凋亡的典型梯状图谱。结论:HCY的促细胞增殖作用可能是通过氧化应激介导的,而Se-Met可以拮抗HCY的促平滑肌细胞增殖作用。因实验结果未见与细胞凋亡有关,Se-Met浓度与谷胱苷肽过氧化物酶(GSH-Px)活性呈正相关,故考虑Se-Met作用机制之一是与细胞的氧化应激反应有关。

Objective To research the methanism of the inhibitive effect of selenium on proliferation of rabbit vascular smooth muscle cells(VSMCs) induced by homocysteine(HCY). Methods Different concentration of HCY(250、500、1 000、2 000、4 000 μmol/L)were added to cultured VSMCs,which the most suitable concentration was sorted out from. Different concentrations of selenomethionine (Se Met,50、100、200 μmol/L)were added to cultured VSMCs treated with 1 000 μmol/L HCY previously. The apoptosis bodies was observed by Giemsa staining,the apoptosis peak was detected by flow cytometry technique and the DNA ladder was examined by total DNA agarose eletrophoresis. Results Different concentrations of Se Met inhibit the proliferation of VSMCs obviously,but no apoptosis small body. Apoptosis peak and DNA ladder weren't found. Conclusion It is suggested that Selenomethionina has the inhibitive effect on proliferation of VSMCs induced by homocysteine,but the effect is not associated with apoptosis.