基于分子对接技术探讨二苯乙烯苷通过SIRT1-TP途径舒张血管的机制研究

目的: 探讨二苯乙烯苷通过SIRT1-TP途径拮抗血管舒缩功能障碍的具体分子机制。方法: 选用DMT Myograph肌动描计系统,在体外观察二苯乙烯苷拮抗U46619(TP受体特异性激动剂)诱发的血管平滑肌收缩的作用;进一步利用Auto Dock软件将TP受体与二苯乙烯苷进行分子对接,验证其结合活性;用SIRT1抑制剂-尼克酰胺(Nic)及激动剂白藜芦醇(Res)与二苯乙烯苷共同处理后观察U46619诱发的血管平滑肌收缩张力的变化,同时用蛋白免疫印迹法检测血管平滑肌SIRT1及TP受体的蛋白表达水平。结果: 二苯乙烯苷对U46619预收缩的血管平滑肌具有舒张作用,其与TP受体的结合能≤ －6 kcal·mol^-1,二者有较好的亲和力;Nic可阻断二苯乙烯苷的舒张血管的作用,而Res可使其舒张作用增强;蛋白免疫印迹检测结果显示二苯乙烯苷可增加血管平滑肌SIRT1蛋白的表达,显著降低TP受体的表达水平。结论: 二苯乙烯苷可通激活SIRT1通路,抑制血管平滑肌TP受体的激活,从而发挥舒张血管的作用。

Study on the mechanism of stilbene glycosides vasodilation via SIRT1-TP pathway based on molecular docking technology

OBJECTIVE To investigate the specific molecular mechanisms of stilbene glycosides antagonizing vasodilatory dysfunction via SIRT1-TP pathway.METHODS The DMT Myograph inotrope system was used to observe the antagonistic effect of stilbene glycosides on the contraction of vascular smooth muscle induced by U46619 (TP receptor-specific agonist). Furthermore, molecular docking was performed between stilbene glycosides and TP receptors by using Auto Dock software to verify the binding activity. Nniacinamide (Nic), a SIRT1 inhibitor, and resveratrol (Res), an agonist, were co-treated with stilbene glucosides to observe the changes in contractile tone of vascular smooth muscle induced by U46619, and the protein expression levels of TP receptors in vascular smooth muscle were also detected by protein immunoblotting.RESULTS Stilbene glycosides had a diastolic effect on U46619 preconstricted vascular smooth muscle with binding energy ≤-6 kcal·mol^-1 to TP receptors with good affinity between them; SIRT1 inhibitor-nicotinamide (Nic) blocked the diastolic effect of stilbene glycosides, while the agonist resveratrol (Res) enhanced its diastolic effect. WB results showed that stilbene glycosides increased the expression of SIRT1 protein in vascular smooth muscle and significantly decreased the expression level of TP receptors.CONCLUSION Stilbene glycosides can inhibit the activation of vascular smooth muscle TP receptors by activating SIRT1 pathway, thus exerting a vasodilatory effect.