四种黄芪黄酮类化合物单体对血管内皮细胞功能的保护作用

Protective effects of four kinds of flavonoids of Astragalus membranaceus on the endothelial function

目的观察从甘肃陇西产黄芪中提取的黄酮类化合物芒柄花素、毛蕊异黄酮-7-o-β-D-吡喃葡萄糖(CG)、毛蕊异黄酮和2'-OH-3',4'-二甲氧基异黄烷-7-o-β-D-吡喃葡萄糖(DG)对血管紧张素Ⅱ(AngⅡ)致人脐静脉内皮细胞(HUVECs)损伤的保护作用。方法将芒柄花素、CG、毛蕊异黄酮和DG分别与1μmol/L的AngⅡ共同作用于HUVECs 24 h后,流式细胞仪检测细胞凋亡,采用硝酸还原酶法和放射免疫分析技术分别测定HUVECs上清液中NO和内皮素-1(ET-1)的含量。结果孵育24 h后,AngⅡ组内皮细胞凋亡率明显多于空白对照组(P<0.05),NO释放明显减少(P<0.05),ET-1明显增加(P<0.05),芒柄花素、CG、毛蕊异黄酮和DG可显著抑制AngⅡ诱导的内皮细胞凋亡(P<0.05),同时可以抑制AngⅡ促ET-1分泌(P<0.05),明显促进HUVECs释放NO(P<0.05)。4种黄酮类化合物组间比较,对内皮细胞凋亡、NO及ET-1释放作用差别无统计学意义。结论 AngⅡ可直接引起HUVECs的损伤及功能失调,芒柄花素、CG、毛蕊异黄酮和DG可抑制AngⅡ所致的体外培养的HUVECs损伤,对内皮细胞具有保护作用。

Objective To investigate the protective effects of flavonoids （formononetin, calycosin- 7-o-β-D-glucopyranoside （CG）, calycosin and 2＇-OH-3＇, 4＇-dimethoxyisoflavanone-7-o-β-D-glucopyranoside （DG）） extracted from Astragalus membranaceus planted in Gansu province on angiotensin Ⅱ （AngⅡ ）-induced the injury of human umbilical vein endothelial cells （HUVECs） in vitro. Methods Different groups of cultured HUVECs were incubated with Ang Ⅱ（1 μmol/L）, formononetin, CG, calycosin and DG extracted from Radix astragali planted in Gansu province respectively for 24 hours. The apoptosis of HUVECs was detected by flow cytometry NO and endothelin-1 （ET-1） contents of the HUVECs cultured medium were measured by nitrate reductase method and radioimmunoassay respectively. Results It was found that incubation with Ang Ⅱ for 24 hours increased HUVECs＇ apoptosis （P 〈0.05） and ET-1 content （P 〈0.05） reduced production of NO （P 〈0.05）. Formononetin, CG, calycosin and DG significantly decreased Ang Ⅱ-induced HUVECs＇ apoptosis （P 〈0.05）. They inhibited ET-1 release （all P 〈0.05） and increased NO contents （P 〈0.05）. There were no significant differences between the four kinds of flavones. Conclusion Ang Ⅱ can directly cause endothelial injury and dysfunction, four kinds of flavonoids of Astragalus membranaceus inhibit Ang Ⅱ -induced HUVECs＇ damage in vitro and have demonstrated a protective effect on endothelial cells.