Apelin-13对高尿酸诱导的脂肪细胞氧化应激的作用

Effects of apelin-13 on oxidative stress induced by high uric acid in adipocytes

目的:探讨apelin-13对高尿酸诱导的3T3-L1脂肪细胞氧化应激的作用及其机制。方法:3T3-L1脂肪细胞予以10 mg/dL尿酸刺激,部分细胞予以1μmol/L apelin-13预处理,以100μmol/L H2O2刺激的细胞为阳性对照。48 h后,流式细胞术检测活性氧族(ROS)含量,生化试剂盒检测细胞及培养液上清抗氧化酶[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)]和促氧化酶NADPH氧化酶(NOX)的活性以及丙二醛(MDA)含量,real-time PCR法检测细胞局部肾素-血管紧张素系统(RAS)各组份血管紧张素原(AGT)、血管紧张素转化酶I(ACE1)、血管紧张素II 1型受体(AT1R)和AT2R及血管紧张素II 1型受体相关蛋(APJ)的mRNA表达水平,ELISA法检测细胞及培养液中血管紧张素II(AngⅡ)浓度。结果:10 mg/dL的尿酸明显降低3T3-L1脂肪细胞SOD、GSH-Px和CAT的活性,升高NOX的活性,增加MDA的含量,细胞内ROS的含量相应升高;apelin-13可以显著改善高尿酸诱导的脂肪细胞氧化应激相关指标。在10 mg/dL尿酸的刺激下,脂肪细胞局部RAS各组份的mRNA表达明显上调,细胞及培养液的AngⅡ水平增高,APJ的mRNA表达下调;而apelin-13可以部分逆转上述指标。结论:Apelin-13可能通过下调3T3-L1脂肪细胞局部RAS的表达改善高尿酸诱导的氧化应激。

AIM:To study the effects of apelin-13 on oxidative stress induced by high uric acid in 3 T3-L1 adipocytes and its underlying mechanisms.METHODS:3 T3-L1 adipocytes were stimulated with uric acid at 10 mg/dL for 48 h.Some of the adipocytes were administered with 1μmol/L apelin-13 in the presence of uric acid at 10 mg/dL.The adipocytes stimulated with 100μmol/L H2O2 were served as positive controls.The intracellular reactive oxygen species(ROS)concentrations were detected by flow cytometry.The biochemical kits were used to measure the activities of superotide dismutase(SOD),glutathione peroxidase(GSH-Px),catalase(CAT)and NADPH oxidase(NOX)activity,and the content of malondialdehyde(MDA)in the cell lysate and the supernatant.The mRNA levels of renin-angiotensin system(RAS)components,including angiotensinogen(AGT),angiotensin-converting enzyrne1(ACE1),angiotensin II type 1 receptor(AT1 R)and AT2 R,as well as angiotensin II receptor-like 1(APJ)were measured by real-time PCR.The concentrations of angiotensin II(AngⅡ)in the cell lysate and the supernatant were measured by ELISA.RESULTS:Adipocytes stimulated with uric acid at 10 mg/dL had lower activities of antioxidant enzymes(SOD,GSH-PX and CAT)and higher levels of NOX activity and MDA content(P<0.05).Accordingly,the intracellular ROS levels were found to be dramatically increased.However,apelin-13 administration attenuated uric acid-induced oxidative stress in the 3 T3-L1 adipocytes.Uric acid at 10 mg/dL upregulated the mRNA expression of local RAS,enhanced AngⅡconcentrations both in the cell lysate and the supernatant,and down-regulated the mRNA level of APJ in the adipocytes(P<0.05).Conversely,apelin-13 partially reversed these parameters.CONCLUSION:Apelin-13 attenuates oxidative stress induced by uric acid,may be via down-regulation of local RAS expression in the 3 T3-L1 adipocytes.