TY - JOUR AB - Oxidative stress serves a role in endothelial dysfunction exhibited by patients with diabetes mellitus. Astragaloside IV (AS‑IV) is a major active ingredient of Radix Astragali, which is considered to exhibit vasoprotective effects through unknown mechanisms. Thus, the current study was performed to investigate the protective effects of AS‑IV in streptozotocin (STZ)‑induced endothelial dysfunction and to explore whether antioxidant mechanisms were involved. The protective effects of AS‑IV on the endothelium‑dependent relaxation and contraction of aortic rings were determined by isometric tension recordings. NADPH subunits and endothelial nitric oxide synthase (eNOS) expression was identified via western blotting. Superoxide dismutase and malondialdehyde levels were assayed using ELISA. Furthermore, the generation of reactive oxygen species (ROS) and nitric oxide (NO) was detected via dihydroethidium and 4,5‑diaminofluorescein diacetate staining, respectively. The results revealed that STZ‑injected mice exhibited increased aortic endothelium‑dependent vasoconstriction and decreased vasorelaxation to acetylcholine. However, AS‑IV treatment reversed these effects. NG‑nitro‑L‑arginine was subsequently used to completely inhibit impaired relaxation. Accordingly, impaired NO generation was restored following AS‑IV treatment by increasing eNOS phosphorylation levels. Furthermore, ROS formation was also depressed following AS‑IV treatment compared with that in STZ‑injected mice. AS‑IV also decreased the expression of various NADPH subunits, including human neutrophil cytochrome b light chain, neutrophil cytosolic factor 1, NADPH oxidase (NOX)2, NOX4 and Rac‑1. The results of the current study may provide novel evidence that diabetes‑induced vascular injury arises from either the inhibition of eNOS or the activation of NOX‑derived ROS generation. In addition, the results warrant further investigation into the application of AS‑IV treatment, leading to the improvement of oxidative stress, in patients with diabetes exhibiting endothelial dysfunction. AD - Department of Nephrology, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200062, P.R. China Laboratory of Renal Disease, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200062, P.R. China AU - Zhang,Yang AU - Mao,Xiao-Dong AU - Cao,Ai-Li AU - Chu,Shuang AU - Li,Zhi-Jun AU - Wang,Yun-Man AU - Peng,Wen AU - Wang,Li AU - Wang,Hao DA - 2021/11/01 DO - 10.3892/etm.2021.10631 IS - 5 JO - Exp Ther Med KW - diabetic vascular complications endothelial dysfunction oxidative stress nitric oxide astragaloside IV PY - 2021 SN - 1792-0981 1792-1015 SP - 1197 ST - Astragaloside IV prevents endothelial dysfunction by improving oxidative stress in streptozotocin‑induced diabetic mouse aortas T2 - Experimental and Therapeutic Medicine TI - Astragaloside IV prevents endothelial dysfunction by improving oxidative stress in streptozotocin‑induced diabetic mouse aortas UR - https://doi.org/10.3892/etm.2021.10631 VL - 22 ER -