Guangdong Medical University, Zhanjiang, Guangdong 524023, P.R. China.
Department of Cardiology, Huangpu Division of The First Affiliated Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510700, P.R. China.
Int J Mol Med. 2018 May;41(5):2865-2878. doi: 10.3892/ijmm.2018.3507. Epub 2018 Feb 22.
Angiotensin (Ang)‑1‑7, which is catalyzed by angiotensin‑converting enzyme 2 (ACE2) from angiotensin‑II (Ang‑II), exerts multiple biological and pharmacological effects, including cardioprotective effects and endothelial protection. The Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway has been demonstrated to be involved in diabetes‑associated cardiovascular complications. The present study hypothesized that Ang‑(1‑7) protects against high glucose (HG)‑induced endothelial cell injury and inflammation by inhibiting the JAK2/STAT3 pathway in human umbilical vein endothelial cells (HUVECs). HUVECs were treated with 40 mmol/l glucose (HG) for 24 h to establish a model of HG‑induced endothelial cell injury and inflammation. Protein expression levels of p‑JAK2, t‑JAK2, p‑STAT3, t‑STAT3, NOX‑4, eNOS and cleaved caspase‑3 were tested by western blotting. CCK‑8 assay was performed to assess cell viability of HUVECs. Apoptotic cell death was analyzed by Hoechst 33258 staining. Mitochondrial membrane potential (MMP) was obtained using JC‑1. Superoxide dismutase (SOD) activity was tested by SOD assay kit. Interleukin (IL)‑1β, IL‑10, IL‑12 and TNF‑α levels in culture media were tested by ELISA. The findings demonstrated that exposure of HUVECs to HG for 24 h induced injury and inflammation. This injury and inflammation were significantly ameliorated by pre‑treatment of cells with either Ang‑(1‑7) or AG490, an inhibitor of the JAK2/STAT3 pathway, prior to exposure of the cells to HG. Exposure of the cells to HG also increased the phosphorylation of JAK2/STAT3 (p‑JAK2 and p‑STAT3). Increased activation of the JAK2/STAT3 pathway was attenuated by pre‑treatment with Ang‑(1‑7). To the best of our knowledge, the findings from the present study provided the first evidence that Ang‑(1‑7) protects against HG‑induced injury and inflammation by inhibiting activation of the JAK2/STAT3 pathway in HUVECs.
血管紧张素（Ang）-1-7 由血管紧张素转换酶 2（ACE2）从血管紧张素- II（Ang-II）催化产生，发挥多种生物学和药理学作用，包括心脏保护作用和内皮保护作用。Janus 激酶 2（JAK2）/信号转导和转录激活因子 3（STAT3）途径已被证明参与糖尿病相关心血管并发症。本研究假设 Ang-（1-7）通过抑制人脐静脉内皮细胞（HUVEC）中的 JAK2/STAT3 途径来防止高葡萄糖（HG）诱导的内皮细胞损伤和炎症。用 40mmol/L 葡萄糖（HG）处理 HUVEC 24h 建立 HG 诱导的内皮细胞损伤和炎症模型。通过蛋白质印迹法检测 p-JAK2、t-JAK2、p-STAT3、t-STAT3、NOX-4、eNOS 和 cleaved caspase-3 的蛋白表达水平。CCK-8 法检测 HUVEC 细胞活力。Hoechst 33258 染色分析细胞凋亡。JC-1 检测线粒体膜电位（MMP）。SOD 测定试剂盒检测超氧化物歧化酶（SOD）活性。ELISA 法检测培养基中白细胞介素（IL）-1β、IL-10、IL-12 和 TNF-α水平。结果表明，HUVEC 暴露于 HG 24h 可诱导损伤和炎症。用 Ang-（1-7）或 JAK2/STAT3 途径抑制剂 AG490 预处理细胞后，可显著改善细胞暴露于 HG 后的损伤和炎症。细胞暴露于 HG 还增加了 JAK2/STAT3 的磷酸化（p-JAK2 和 p-STAT3）。Ang-（1-7）预处理可减弱 JAK2/STAT3 途径的激活。据我们所知，本研究的结果首次提供了证据，表明 Ang-（1-7）通过抑制 HUVEC 中 JAK2/STAT3 途径的激活来防止 HG 诱导的损伤和炎症。
