血管紧张素(1-7)通过抑制JAK/STAT信号通路对抗高糖诱导的人脐静脉内皮细胞损伤

摘要

AIM:To investigate whether angiotensin (1-7) [Ang-(1-7)] protects human umbilical vein endo-thelial cells (HUVECs) against high glucose-induced injury by inhibiting JAK/STAT signaling pathway .METHODS:The cell viability was examined by CCK-8 assay.The expression levels of JAK2, STAT3, p-JAK2, p-STAT3, cleaved caspase-3 and endothelial nitric oxide synthase ( eNOS) were detected by Western blot .The number of apoptotic cells was observed by photofluorography with Hoechst 33258 nuclear staining.The intracellular levels of reactive oxygen species (ROS) were tested by DCFH-DA staining followed by photofluorography .RESULTS:Expose of the HUVECs to high glucose (40 mmol/L) for different time significantly increased phosphorylation level of JAK 2 which reached the peak at 24 h.The protein level of p-STAT3 significantly increased at 24~48 h and reached the peak at 36 h.The expression of cleaved caspasep-3 was signifi-cantly up-regulated at 12~24 h, and the expression of eNOS gradually decreased at 3~48 h with prolongation of time .Pre-treatment of the HUVECs with Ang-(1-7) at 2μmol/L or AG490 (an inhibitor of JAK/STAT pathway) at 20μmol/L for 0.5 h before exposure of the cells to high glucose for 24 h markedly attenuated high glucose-induced injury of the HUVECs , by in-creasing the cell viability and eNOS expression , and decreasing the apoptotic cells , ROS production and cleaved caspase-3 expression.Furthermore, pretreatment with Ang-(1-7) for 0.5 h also decreased the protein levels of p-JAK2 and p-STAT3.CONCLUSION:Ang-(1-7) protects the HUVECs against high glucose-induced injury by inhibiting JAK/STAT signaling pathway .%目的:研究血管紧张素(1-7)[Ang-(1-7)]能否通过抑制JAK/STAT信号通路对抗高糖诱导的人脐静脉内皮细胞(HUVECs)损伤.方法:CCK-8检测细胞存活率;Western blot法检测内皮细胞JAK2、STAT3、p-JAK2、p-STAT3、cleaved caspase-3和内皮型一氧化氮合酶(eNOS)的蛋白水平;Hoechst 33258染色荧光显微镜照相法检测内皮细胞凋亡数量;DCFH-DA染色荧光显微镜照相法检测内皮细胞内活性氧簇(ROS)的水平.结果:应用高糖(40 mmol/L)处理HUVECs 12~48 h能明显上调JAK2的磷酸化水平,于24 h达最高峰;在24~48 h能明显上调STAT3的磷酸化水平,于36 h最高;在12~24 h能明显上调cleaved caspase-3的表达,在3~48 h随着时间延长,eNOS的表达逐渐降低.2μmol/L的Ang-(1-7)或20μmol/L的JAK/STAT通路抑制剂AG490预处理0.5 h可显著抑制由高糖引起的内皮细胞损伤,表现为p-STAT3、p-JAK2及cleaved caspase-3蛋白水平降低、细胞存活率及eNOS表达升高,细胞凋亡数量和胞内ROS生成减少.结论:Ang-(1-7)能通过抑制JAK/STAT通路对抗高糖诱导的人脐静脉内皮细胞损伤.