Department of Thoracic Vascular Surgery, Beijing Daxing District People's Hospital, No. 26 Huangcun West Street, Daxing District, Beijing, 102600, China.
Int Urol Nephrol. 2023 Feb;55(2):423-436. doi: 10.1007/s11255-022-03325-y. Epub 2022 Aug 12.
Diabetic nephropathy (DN) is a severe microvascular complication of diabetes mellitus and a primary reason for end-stage renal disease (ESRD). Isorhapontigenin (ISO), a natural derivative of stilbene, has significant anti-inflammatory and antioxidant effects. Nevertheless, its impact on DN remains elusive.
Human vascular endothelial cells (HUVECs) and podocytes were damaged by high glucose (HG). Cell viability and apoptosis were testified by the cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The mRNA profiles of antioxidant factors HO-1, NQO1, and Prx1 were monitored by real-time quantitative polymerase chain reaction (RT-qPCR). Western blotting (WB) was implemented to verify the expression of apoptosis-related proteins (Bax, Bad, and Bcl-XL), antioxidant factors (HO-1, NQO1, and Prx1), autophagy-related proteins (Beclin-1, ATG5, p62), podocalyxin (podocin, nephrin, and synaptopodin) and the AMPK/Nrf2 pathway. The levels of oxidative stress-related markers MDA, SOD and CAT were assessed with the corresponding kits. Compound C (CC), an inhibitor of AMPK, was deployed to probe the effects of modulating the AMPK/Nrf2 pathway on ISO in oxidative stress and autophagy in HUVECs and podocytes. Streptozotocin (STZ) was injected intraperitoneally into mice to establish an animal model of diabetes mellitus and to clarify the impact of ISO on the renal parameters such as serum creatinine, urea nitrogen and urinary protein in diabetic mice.
ISO notably facilitated cell proliferation, impeded apoptosis, elevated the expression of antioxidant-related factors, alleviated HG-induced oxidative stress and activated autophagy in HUVECs and podocytes. ISO activated the AMPK/Nrf2 pathway. Attenuating AMPK diminished the protective effect of ISO on HUVECs and podocytes, curbed cell proliferation, intensified apoptosis and oxidative stress, and dampened autophagy. In-vivo experiments also displayed that ISO reduced histopathological damage, lowered serum creatinine, urea nitrogen and urinary ACR levels, and eased kidney damage in DN mice.
ISO attenuates HG-induced oxidative stress and activates autophagy by motivating the AMPK/Nrf2 pathway, exerting a protective effect on HUVECs and podocytes and reducing renal injury in DN mice.
糖尿病肾病（DN）是糖尿病的一种严重的微血管并发症，也是终末期肾病（ESRD）的主要原因。异甘草素（ISO）是一种天然的芪类衍生物，具有显著的抗炎和抗氧化作用。然而，其对 DN 的影响尚不清楚。
高糖（HG）损伤人血管内皮细胞（HUVECs）和足细胞，通过细胞计数试剂盒-8（CCK-8）法和流式细胞术分别检测细胞活力和细胞凋亡，实时定量聚合酶链反应（RT-qPCR）监测抗氧化因子 HO-1、NQO1 和 Prx1 的 mRNA 谱，通过 Western blot（WB）验证凋亡相关蛋白（Bax、Bad 和 Bcl-XL）、抗氧化因子（HO-1、NQO1 和 Prx1）、自噬相关蛋白（Beclin-1、ATG5、p62）、足突蛋白（podocin、nephrin 和 synaptopodin）和 AMPK/Nrf2 通路的表达。用相应试剂盒测定氧化应激相关标志物 MDA、SOD 和 CAT 的水平。用 AMPK 抑制剂 Compound C（CC）来探究调节 AMPK/Nrf2 通路对 ISO 在 HUVECs 和 podocytes 中氧化应激和自噬的影响。用链脲佐菌素（STZ）腹腔注射建立糖尿病小鼠动物模型，阐明 ISO 对糖尿病小鼠肾脏参数（如血清肌酐、尿素氮和尿蛋白）的影响。
ISO 显著促进细胞增殖，抑制细胞凋亡，上调抗氧化相关因子的表达，减轻 HG 诱导的氧化应激，激活 HUVECs 和 podocytes 的自噬。ISO 激活了 AMPK/Nrf2 通路。抑制 AMPK 减弱了 ISO 对 HUVECs 和 podocytes 的保护作用，抑制细胞增殖，加剧细胞凋亡和氧化应激，抑制自噬。体内实验也显示 ISO 减轻了组织病理学损伤，降低了血清肌酐、尿素氮和尿 ACR 水平，减轻了 DN 小鼠的肾脏损伤。
ISO 通过激活 AMPK/Nrf2 通路减轻 HG 诱导的氧化应激和激活自噬，对 HUVECs 和 podocytes 发挥保护作用，减少 DN 小鼠的肾损伤。
