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

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、pJAK2、p-STAT3、cleaved caspase-3和内皮型一氧化氮合酶(e NOS)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,e NOS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e NOS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。

Angiotensin (1-7) protects human umbilical vein endothelial cells against high glucose-induced injury by inhibiting JAK/STAT signaling pathway

AIM: To investigate whether angiotensin (1-7) protects human umbilical vein endothelial 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 JAK2 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 significantly up-regulated at 12~24 h, and the expression of eNOS gradually decreased at 3~48 h with prolongation of time. Pretreatment of the HUVECs with Ang-(1-7) at 2 μmol/L or AG490 (an inhibitor of JAK/STAT pathway) at 20 μmol/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 increasing 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.