白藜芦醇甙减轻高糖所致心肌微血管内皮细胞损伤的作用及机制研究

目的:探讨白藜芦醇甙在高糖处理的大鼠心肌微血管内皮细胞损伤中的作用及其可能调控机制。方法:酶消法分离大鼠CMECs,高糖处理CMECs建立细胞损伤模型,实验随机分为6个组:对照组(葡萄糖浓度为5.5 mmol/L)、白藜芦醇甙组、高糖组(葡萄糖浓度为33 mmol/L)、高糖+白藜芦醇甙组、高糖+白藜芦醇甙+3-MA(自噬抑制剂)组和高糖+雷帕霉素(自噬诱导剂)组。白藜芦醇甙组和高糖+白藜芦醇甙组分别加入10μmol/L的白藜芦醇甙孵育24 h,高糖+白藜芦醇甙+3-MA组加入10μmol/L的白藜芦醇甙和10μmmol/L 3-MA孵育24 h,高糖+雷帕霉素组加入100 nmol/L的雷帕霉素孵育24小时。CCK-8实验检测大鼠CMECs增殖;Tunel法检测大鼠CMECs凋亡;FITC-葡聚糖清除实验检测单层CMECs通透性;Western blot检测LC3Ⅱ和p62的表达。结果:与对照组和白藜芦醇甙组相比,高糖组CMECs增殖能力降低(P<0.05),凋亡率显著增加(P<0.05),细胞通透性增加(P<0.05),LC3Ⅱ表达降低(P<0.05),p62的表达增加(P<0.05);与高糖组相比,高糖+白藜芦醇甙组和高糖+雷帕霉素组CMECs增殖能力增加(P<0.05),凋亡率显著降低(P<0.05),细胞通透性降低(P<0.05),LC3Ⅱ表达增加(P<0.05),p62的表达降低(P<0.05);与高糖+白藜芦醇甙组相比,高糖+白藜芦醇甙+3-MA组CMECs增殖能力降低(P<0.05),凋亡率显著增加(P<0.05),细胞通透性增加(P<0.05),LC3Ⅱ表达降低(P<0.05),p62的表达增加(P<0.05)。结论:白藜芦醇甙通过增加自噬减轻高糖处理的大鼠心肌微血管内皮细胞损伤。

Polydatin Decreases the Impairment of CMECs Caused by High Glucose in Rat by Enhancing Autophagy

Objective:To explore the effects and mechanism of polydatin on the impairment of CMECs caused by high glucose.Methods:Collagenase digestion was used to isolate CMECs from the hearts of SD rats.Primary CMECs were randomly divided to 6 groups:low glucose group,low glucose+polydatin group,high glucose group,high glucose+polydatin group,high glucose+polydatin+3-MA(the autophagy inhibitor)group and high glucose+rapamycin(the autophagy inducer)group.Low glucose+polydatin group and high glucose+polydatin group were treated with polydatin(10μmol/L)in the absence or presence of high glucose for 24 h.The high glucose+polydatin+3-MA group was treated with polydatin(10μmol/L)and 3-MA(10μmol/L)in high glucose for 24 h.The high glucose+rapamycin group was treated with rapamycin(100 nmol/L)in high glucose for 24 h.The proliferation of CMECs was evaluated by CCK-8 assay.Apoptotic index of CMECs was examined by TUNEL.FITC-dextran clearance assay was performed to monitor changes in CMEC permeability.Western blot was used to determine the expressions of LC3Ⅱand p62.Results:Compared with low glucose group and low glucose+polydatin group,the proliferation of CMECs decreased significantly(P<0.05),with enhanced apoptotic index and CMEC permeability(P<0.05),as well as downregulated LC3Ⅱlevel and upregulated p62 level(P<0.05)in high glucose group.Compared with high glucose group,the proliferation of CMECs increased significantly(P<0.05),with decreased apoptotic index and CMEC permeability(P<0.05),as well as upregulated LC3Ⅱlevel and downregulated p62 level(P<0.05)in high glucose+polydatin group and in high glucose+rapamycin group.Compared with high glucose+polydatin group,the proliferation of CMECs decreased significantly(P<0.05),with enhanced apoptotic index and CMEC permeability(P<0.05),as well as downregulated LC3Ⅱlevel and upregulated p62 level(P<0.05)in high glucose+polydatin+3-MA group.Conclusion:Polydatin can significantly decrease the impairment of CMECs caused by high glucose in rat by enhancing autophagy.