Department of Diabetes and Endocrine Medicine, Kagoshima University Graduate School of Medicine and Dental Sciences, Kagoshima, Japan.
J Diabetes Investig. 2023 Apr;14(4):548-559. doi: 10.1111/jdi.13981. Epub 2023 Feb 2.
AIMS/INTRODUCTION: The mechanisms underlying the effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors on aortic endothelial dysfunction in diet-induced obesity are not clearly understood. This study investigated whether SGLT2 inhibition by luseogliflozin improved free fatty acid (FFA)-induced endothelial dysfunction in high-fat diet (HFD)-induced obese mice.
Mice were fed a control diet or high-fat diet for 8 weeks, and then each diet with or without luseogliflozin was provided for an additional 8 weeks under free or paired feeding. Afterward, the thoracic aortas were removed and utilized for the experiments.
Luseogliflozin treatment decreased body weight, fasting blood glucose, insulin, and total cholesterol in HFD-fed mice only under paired feeding but not under free feeding. Endothelial-dependent vasodilation under FFA exposure conditions was significantly lower in HFD-fed mice than in control diet-fed mice, and luseogliflozin treatment ameliorated FFA-induced endothelial dysfunction. Reactive oxygen species (ROS) production induced by FFA was significantly increased in HFD-induced obese mice. Luseogliflozin treatment increased the expression of superoxide dismutase 2 (SOD2), an antioxidative molecule, and reduced FFA-induced ROS production in the thoracic aorta. Superoxide dismutase reversed FFA-induced endothelial dysfunction in HFD-fed mice.
It was shown that caloric restriction is important for the effect of luseogliflozin on metabolic parameters and endothelial dysfunction. Furthermore, SGLT2 inhibition by luseogliflozin possibly ameliorates FFA-induced endothelial dysfunction by increasing SOD2 expression and decreasing reactive oxygen species production in the thoracic aorta.
目的/引言:钠-葡萄糖共转运蛋白 2(SGLT2)抑制剂对饮食诱导肥胖动物主动脉内皮功能障碍的作用机制尚不清楚。本研究旨在探讨鲁格列净抑制 SGLT2 是否能改善高脂肪饮食(HFD)诱导肥胖小鼠游离脂肪酸(FFA)诱导的内皮功能障碍。
将小鼠喂饲对照饮食或高脂肪饮食 8 周,然后分别在自由或配对喂养条件下再给予对照饮食或高脂肪饮食加或不加鲁格列净 8 周。之后,取出胸主动脉进行实验。
仅在配对喂养而非自由喂养条件下,鲁格列净治疗可降低 HFD 喂养小鼠的体重、空腹血糖、胰岛素和总胆固醇。FFA 暴露条件下的内皮依赖性血管舒张在 HFD 喂养小鼠中明显低于对照饮食喂养小鼠,而鲁格列净治疗可改善 FFA 诱导的内皮功能障碍。FFA 诱导的活性氧(ROS)产生在 HFD 诱导肥胖小鼠中显著增加。鲁格列净治疗可增加抗氧化分子超氧化物歧化酶 2(SOD2)的表达,减少胸主动脉中 FFA 诱导的 ROS 产生。超氧化物歧化酶逆转了 HFD 喂养小鼠 FFA 诱导的内皮功能障碍。
研究表明热量限制对于鲁格列净对代谢参数和内皮功能障碍的作用是重要的。此外,鲁格列净抑制 SGLT2 可能通过增加胸主动脉中 SOD2 的表达和减少 ROS 产生来改善 FFA 诱导的内皮功能障碍。