抗衰老Klotho蛋白对高糖作用下血管内皮细胞的保护作用

目的:研究抗衰老Klotho蛋白对高糖作用下血管内皮细胞的保护作用及其作用机制。方法:体外培养人脐静脉血管内皮细胞(HUVECs),设置PBS对照组、5.5 mmol/L葡萄糖组、33.3 mmol/L葡萄糖组、0.1μmol/L Klotho+33.3 mmol/L葡萄糖组、1μmol/L Klotho+33.3 mmol/L葡萄糖组和10μmol/L Klotho+33.3 mmol/L葡萄糖组。使用MTT法检测各组细胞活力;同时检测各组细胞培养上清中丙二醛(MDA)的含量以及乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)和还原型谷胱甘肽(GSH)的活性;流式细胞术检测各组细胞中活性氧(ROS)含量变化;ELISA检测各组细胞培养液中一氧化氮(NO)、内皮素1(ET-1)和细胞间黏附分子1(ICAM-1)的浓度变化;Western blot法检测各组细胞中核因子κB(NF-κB)蛋白的表达。结果:与PBS对照组相比,33.3 mmol/L葡萄糖能够显著降低HUVECs的细胞活力,增加细胞中ROS的含量,增加细胞培养上清中LDH活性和MDA含量,降低SOD和GSH的活性,同时降低NO分泌,诱导ET-1、ICAM-1分泌及细胞中NF-κB蛋白的表达(P0.05)。不同浓度Klotho蛋白和33.3 mmol/L高糖同时作用HUVECs时,细胞活力逐渐上升,ROS和MDA含量以及LDH活性逐渐下降,SOD和GSH活性则逐渐上升,同时NO分泌增加,ET-1、ICAM-1分泌及NF-κB蛋白表达显著下降(P0.05)。结论:抗衰老Klotho蛋白能够提升高糖作用下HUVECs的细胞活力,减少高糖诱导的ROS生成及氧化损伤,恢复HUVECs的正常分泌功能,并通过减少NF-κB蛋白表达发挥抗损伤作用。

Protective effect of anti-aging Klotho protein on human umbilical vein endothelial cells treated with high glucose

AIM: To study the protective effect of anti-aging Klotho protein on human umbilical vein endothelial cells (HUVECs) treated with high glucose (HG).METHODS: HUVECs were cultured in vitro, and divided into PBS control group, 5.5 mmol/L glucose group, 33.3 mmol/L glucose group, 0.1 μmol/L Klotho+33.3 mmol/L glucose group, 1 μmol/L Klotho+33.3 mmol/L glucose group, and 10 μmol/L Klotho+33.3 mmol/L glucose group. The viability of the HUVECs was measured by MTT assay. The content of malondialdehyde (MDA), and the activities of lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione (GSH) in cell culture supernatants were observed. The production of reactive oxygen species (ROS) in HUVECs was analyzed by flow cytometry. The levels of nitric oxide (NO), endothelin (ET-1), intercellular adhesion molecule-1 (ICAM-1) in HUVEC culture medium were detected by ELISA. The protein expression of nuclear factor-kappa B (NF-κB) in the HUVECs was determined by Western blot. RESULTS: Compared with PBS control group, 33.3 mmol/L glucose significantly decreased the HUVEC viability, increased ROS, LDH and MDA levels, reduced the activities of SOD and GSH, decreased the NO secretion, and induced the ET-1 and ICAM-1 secretion and the protein expression of NF-κB in HUVECs. When HUVECs were treated with Klotho protein at different concentrations combined with 33.3 mmol/L glucose, the cell viability was increased significantly, the ROS, LDH and MDA levels were decreased significantly, the antioxidant SOD and GSH activities were significantly increased, the secretion of NO was increased, but ET-1 and ICAM-1 releases and protein expression of NF-κB were significantly reduced.CONCLUSION: Anti-aging Klotho protein promotes the viability of HUVECs treated with HG, reduces the oxidative damage and ROS production, and restores the normal secretory function of HUVECs, thus playing a protective role in vascular endothelial cells through reducing the protein expression of NF-κB.