该研究采用分子对接和网络药理学等生物信息学方法,构建中药经典复方小续命汤"成分-血管舒缩G蛋白偶联受体(GPCR)靶点"网络,研究复方小续命汤调控血管舒缩功能的有效成分及潜在靶点。通过"国家人口与健康科学数据共享平台药学数据中心"提供的"中国天然产物化学成分库"、TCMSP数据库及文献检索收集复方小续命汤12味中草药所含的化学成分,经过类药性和代谢性质等的预测与筛选后,建立分子库。利用RCSB Protein Data Bank数据库和Discovery Studio 4.1内置建模工具获得与血管舒缩相关的5类GPCR:5-羟色胺1A及1B受体(5-HT1AR,5-HT1BR)、血管紧张素Ⅱ1型受体(AT1R)、β2肾上腺素能受体(β2-AR)、尾加压素Ⅱ受体(hUTR)和内皮素受体B(ETB)及相关活性位点。将分子库与靶点进行Libdock分子对接,取每个靶点评分最高的50个化合物进行统计。收集到的数据通过Cytoscape 3.4.0进行化学成分和靶点的网络建模和分析。结果表明,复方小续命汤大多数化学成分作用于不同的血管舒缩相关GPCR靶点,少数有效成分可同时作用于多个GPCR靶点,并形成协同效应达到舒张血管的效果。
Objective To study the role of sirtuin 1 （SIRT1） in Fas ligand （FasL） expression regulation during vascular lesion formation and to elucidate the potential mechanisms. Methods SIRT1 and FasL protein levels were detected by Western blotting in either mouse arteries extract or the whole rat aortic vascular smooth muscle cell （VSMC） lysate. Smooth muscle cell （SMC）-specific human SIRT1 transgenic （Tg） C57BL/6 mice and their littermate wild-type （WT） controls underwent complete carotid artery ligation （ligation groups） or the ligation-excluded operation （sham groups）. The carotid arteries were collected 1 day after operation. Reverse transcription-polymerase chain reaction was performed to detect the mRNA levels of SIRT1 and FasL. Luciferase reporter assays were performed to detect the effect of WT-SIRT1, a dominant-negative form of SIRT1 （SIRT1H363Y）, and GATA-6 on the promoter activity of FasL. Flow cytometry assay was applied to measure the hypodiploid DNA content of VSMC so as to monitor cellular apoptosis. Results SIRTI was expressed in both rat aortic VSMCs and mouse arteries. Forced SIRT1 expression increased FasL expression both in injured mouse carotid arteries 1 day after ligation （P〈0.001） and VSMCs treated with serum （P〈0.05 at the transcriptional level, P〈0.001 at the protein level）. No notable apoptosis was observed. Furthermore, transcription factor GATA-6 increased the promoter activity of FasL （P〈0.001）. The induction of FasL promoter activity by GATA-6 was enhanced by WT-SIRT1 （P〈0.001）, while SIRT1H363Y significantly relieved the enhancing effect of WT-SIRT1 on GATA-6 （P〈0.001）. Conclusions Overexpression of SIRT1 up-regulates FasL expression in both flow-restricted mouse carotid arteries and serum-stimulated VSMCs. The transcription factor GATA-6 participates in the transcriptional regulation of FasL expression by SIRT 1.
Li LiPeng GaoHou-zao ChenZhu-qin ZhangTing-ting XuYu-yan JiaHui-na ZhangGuan-hua DuDe-pei Liu
OBJECTIVE To investigate the vasorelaxant effect of pinocembrin(5,7-dihydroxyflavanone),one of the main flavonoids in propolis,on angiotensinⅡ(AngⅡ)induced vasoconstriction and the molecular mechanism of action.METHODS The isometric vascular tone was measured in thoracic aortic rings from SD rat,and the effects of pinocembrin on the single dose and concentration cumulative response curves of AngⅡ were recorded.The binding of pinocembrin to the angiotensin type 1 receptor(AT1R)was studied by using molecule docking analysis.Intracellular[Ca2+]([Ca2+]i)was measured with Fura2/AM in VSMCs.The phosphorylation levels of myosin light chain 2(MLC2)and myosin phosphatase target unit 1(MYPT1),and protein level of Rho kinase 1(ROCK1)in the rat aortic rings were detected by Western blotting.RESULTS Pinocembrin was observed to inhibit AngⅡ-induced vasoconstriction in rat aortic rings with either intact or denuded endothelium.In endothelium-denuded tissues,pinocembrin(pD′2 4.28±0.15)counteracted the contractions evoked by cumulative concentrations of AngⅡ.In a docking model,pinocembrin showed effective binding at the active site of AT1R.Pinocembrin was shown to inhibit both AngⅡ-induced Ca2+ release from internal stores and Ca2+ influx.Moreover,the increase in the phosphorylation of MLC2 and MYPT1,and the increased protein level of ROCK1 induced by AngⅡ was blocked by pinocembrin.CONCLUSION Pinocembrin inhibits AngⅡ-induced rat aortic ring contraction in a Ca2+-dependent and Ca2+-independent manner via blocking AT1R.
Li LIHai-guang YANGXiao-bin PANGBai-nian CHENLi GAOLe WANGShou-bao WANGTian-yi YUANSu-bo WANGDe-pei LIUGuan-hua DU
