成纤维细胞生长因子21对缺氧复氧心肌细胞的保护作用及机制研究

The protective effects and potential mechanisms of FGF21 on myocardial hypoxia/reoxygenation injury

目的探讨成纤维细胞生长因子21(FGF21)对缺氧复氧(H/R)心肌细胞的保护作用及对PI3K/AKT通路的影响。方法重组腺病毒载体Ad-FGF21诱导原代心肌细胞过表达FGF21。腺病毒转染心肌细胞后构建H/R损伤模型(3h缺氧联合3h复氧)。实验分为对照组(Con组)、H/R组、H/R+Ad-GFP组、H/R+Ad-FGF21组4组。心肌细胞存活率评估细胞损伤程度;SOD/MDA检测联合DHE荧光染色评估氧化应激反应(ROS);流式细胞术评估细胞凋亡;Western blot检测相关蛋白水平。在机制探讨实验中给予PI3K/AKT抑制剂(LY294002)进行干预。结果与Con组相比,H/R损伤后FGF21蛋白表达显著下调,并伴随心肌细胞活性降低、ROS与凋亡反应激活。腺病毒介导的心肌细胞过表达FGF21能够明显抑制H/R损伤,表现为细胞活力、ROS与凋亡反应均有不同程度改善。FGF21心肌细胞过表达能够增加PI3K/AKT磷酸化水平,而抑制PI3K/AKT通路后FGF21过表达介导的细胞保护功能被逆转。结论 FGF21主要通过PI3K/AKT依赖性途径改善心肌细胞H/R损伤。

Objective To measure the roles of fibroblast growth factor 21 (FGF21) on hypoxia/reoxygenation (H/R)-treated cardiomyocytes and the potential mechanisms.Methods Adenoviral vector encoding FGF21 (Ad-FGF21) was used to elevate FGF21 in cultured neonatal rat cardiomyocytes.The experiments were assigned into four groups:control group,H/R group,H/R+Ad-GFP group and H/R+ Ad-FGF21 group.Three hours of hypoxia and 3h of reoxygenation were performed to cause H/R injury followed after viral transfection.Cell viability was detected by CCK-8 assay.The apoptosis,ROS and molecular alternations were systematically estimated.Moreover,the specific PI3K/AKT inhibitor (LY294002) was added in mechanistic detections.Results In comparison with the control group,H/R resulted in the down-regulation of FGF21 followed by the worsened cardiomyocytes damage,as exhibited by the decrease of viability and the promotion of ROS and apoptosis.However,above parameters induced by H/R were attenuated by FGF21 overexpression.Mechanistic experiments showed that FGF21 elevation enhanced the levels of p-PI3K/AKT,and blocking PI3K/AKT with its specific inhibitor LY294002 dampened the H/R-limited effects of FGF21.Conclusion FGF21 ameliorates myocardial H/R injury in part via a PI3K/AKT-dependent way.