Pyr1-apelin-13对大鼠心肌成纤维细胞AMPK/mTOR自噬信号和氧化应激损伤的影响

目的探讨Pyr¹-apelin-13对于大鼠心肌成纤维细胞自噬和氧化应激的影响及其作用机制。方法提取新生大鼠心肌成纤维细胞(CFs),给与血管紧张素Ⅱ(AngⅡ),Pyr¹-apelin-13,雷帕霉素干预,使用Western blot法和免疫荧光技术检测自噬信号分子,使用DHE法检测氧自由基生成,观察Pyr¹-apelin-13在AMPK/mTOR通路中的作用。结果在体外培养的CFs细胞中,AngⅡ刺激通过上调P62和磷酸化mTOR抑制自噬水平,伴有LC3II、Beclin-1和磷酸化AMPK降低及氧化应激水平增高;而Pyr¹-apelin-13或雷帕霉素干预后逆转AngⅡ介导的自噬下调,表现为LC3II/I、Beclin-1和磷酸化AMPK水平上升,P62表达和磷酸化mTOR下降,细胞氧化应激损伤减轻。结论Pyr¹-apelin-13可通过调控大鼠心肌成纤维细胞AMPK/mTOR自噬信号发挥其抗氧化和促自噬的细胞保护功效。

Effects of Pyr1-apelin-13 on the AMPK-mTOR Autophagy Signaling and Oxidative Stress in Rat Cardiofibroblasts

Objective To investigate the impacts and underlying mechanisms of Pyr¹-apelin-13 on autophagy and oxidative stress in rat cardiofibroblasts(CFs).Methods Neonatal rat CFs were isolated and cultured from hearts from 1-or 3-day-old Sprague-Dawley rats.The role of the AMPK/mTOR pathway in the regulation of CFs by Pyr¹-apelin-13 was observed by the means of applying AngⅡ,Pyr¹-apelin-13 and rapamycin.Autophagy related protein expression was studied by Western blot and immunofluorescence,respectively.Dihydroethidium(DHE)staining was used to detect oxidative stress levels of rat CFs.Results Compared with control group,angiotensin(Ang)Ⅱprevented autophagy levels in rat CFs by promoting expression of P62 and phosphorylated level of mTOR.These were associated with increased level of oxidative stress and decreased levels of LC3-Ⅱand phosphorylated levels of AMPK.Administration of Pyr¹-apelin-13 or rapamycin reduced the oxidative stress and reversed AngⅡ-mediated loss of autophagy in rat CFs with increased levels of LC3-Ⅱand p-AMPK and downregulated levels of P62 protein and p-mTOR.Conclusion Pyr¹-apelin-13 exerts cellular protective effects with anti-oxidant and pro-autophagic actions in rat CFs by regulating the AMPK/mTOR signaling pathway.