| 引用本文： |
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陈友铭,陈媛媛,陈宇涵,等.血管紧张素Ⅱ通过激活小G蛋白Rac1上调FGF13致心肌细胞肥大的机制研究[J].同济大学学报（医学版）,2020,41(2):192-197,204. [点击复制]
- CHEN You-ming,CHEN Yuan-yuan,CHEN Yu-han,et al.Angiotension Ⅱ induces cardiomyocyte hypertrophy through Rac1-mediated upregulation of FGF13[J].同济大学学报（医学版）,2020,41(2):192-197,204. [点击复制]
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| 摘要: |
| 目的探究血管紧张素Ⅱ（angiotensin Ⅱ, Ang Ⅱ）通过激活小G蛋白Rac1促进心肌细胞肥大的机制。方法构建Ad-Rac1、Ad-Rac1-V12腺病毒，转染HEK293T细胞，收集样本并通过基因芯片筛选出有表达差异的基因。将上述2种腺病毒转染心肌细胞，通过GST pull down实验检测Active Rac1的表达情况。通过Western印迹法检测成纤维细胞生长因子13（fibroblast growth factor 13, FGF13）的表达差异。将乳鼠心肌细胞转染siRNA，并分成4个实验组进行处理：Ad-Vector组、Ad-Rac1组、Ad-Rac1-V12组、共转染Ad-Rac1-V12及FGF13-Si3组，检测各组心房利钠肽（atrial natriuretic peptide, ANP）、β-肌球蛋白重链（β-myosin heavy chain, β-Mhc）表达差异及心肌细胞面积的变化。采用Ang Ⅱ刺激心肌细胞，并加入Rac1特异性抑制剂NSC23766，检测各组FGF13表达差异以及心肌细胞面积的变化。结果基因芯片结果表明Ad-Rac1-V12组有402个相对于Ad-Rac1组的差异基因，其中FGF13上调（28±1.2）倍。与Ad-Rac1组相比，Ad-Rac1-V12组Active Rac1、FGF13表达显著上调（P<0.05）。与Ad-Rac1-V12组相比，共转染Ad-Rac1-V12及siRNA-3组的Anp、β-Mhc表达显著降低（P<0.05），心肌细胞表面积明显减小（P<0.05）。与对照组相比，Ang Ⅱ刺激组Anp、β-Mhc、Active Rac1、FGF13表达明显上调，心肌细胞表面积增加。与Ang Ⅱ刺激组相比，Ang Ⅱ+NSC23766组FGF13表达明显下调，心肌细胞面积减少（P<0.05）。结论血管紧张素Ⅱ通过激活小G蛋白Rac1来上调FGF13的表达可能是其导致心肌细胞肥大的一条新通路。 |
| 关键词: 心肌肥大 血管紧张素Ⅱ Rac1 Rac1-V12 成纤维细胞生长因子13 |
| DOI：10.16118/j.1008-0392.2020.02.009 |
| 投稿时间：2019-08-24 |
| 基金项目:国家自然科学基金（81470497） |
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| Angiotension Ⅱ induces cardiomyocyte hypertrophy through Rac1-mediated upregulation of FGF13 |
| CHEN You-ming,CHEN Yuan-yuan,CHEN Yu-han,YANG Zhen-wei,ZHOU Lei,Wang Yue-peng |
| (Dept. of Cardiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China;Dept. of Emergency, Yejishan Hospital, Wannan Medical College, Wuhu 241001, Anhui Province, China;Dept. of Cardiothoracic Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China) |
| Abstract: |
| ObjectiveTo explore the mechanism of angiotensinⅡ(Ang Ⅱ) mediated activation of small GTPase Rac1 in Ang Ⅱ-induced cardiac hypertrophy. MethodsAdenoviruses encoding wild-type Rac1(Ad-Rac1) and constitutively-active mutant Rac1-V12(Ad-Rac1-V12) were constructed. The activity of Rac1 was assayed by GST pull down experiments after neonate rat cardiomyocyte(NRCs) were transfected with the adenoviruses. Western blotting was performed to detect the expression of fibroblast growth factor 13(FGF13). NRCs were transfected with siRNA and divided into 4 groups：Ad-Vector, Ad-Rac1, Ad-Rac1-V12 and Ad-Rac1-V12+FGF13-si3. The surface area of cardiomyocyte and expressions of atrial natriuretic peptide(Anp) and β-myosin heavy chain(β-Mhc) were measured and detected. NRCs were treated with Ang Ⅱ and Rac1 specific inhibitor NSC23766. The activity of Rac1 was assayed by Rac1-GTP pull-down experiments. ResultsAfter confirmation of the adenoviruses-mediated overexpressions of WT Rac1 and Rac1-V12 in HEK293T cells by Western blotting, the transfected cells were further processed for gene chip analysis. Totally, 402 differentially expressed genes were obtained for Ad-Rac1-V12 vs Ad-Rac1. Of them, FGF13 was significantly upregulated for 28±1.2 folds(P<0.05). NRCs were further transfected with the adenoviruses and the upregulation of FGF13 was confirmed. Compared to Rac1-transfected NRCs, cells overexpressing Rac1-V12 demonstrated significantly activated Rac1(P<0.05). As compared to NRCs transfected with Ad-Rac1-V12, NRCs transfected with Ad-Rac1-V12+FGF13-si3 exhibited significantly lower Anp and β-Mhc levels and surface area of cardiomyocytes(P<0.05). Ang Ⅱ mildly upregulated total Rac1 expression, significantly activated Rac1, remarkably potentiated FGF13 expression, and enlarged the cell surface area (P<0.05). However, in cells with pretreatment of Rac1-specific inhibitor NSC23766, Ang Ⅱ stimulation unchanged total Rac1 expression, activated less Rac1, did not upregulated FGF13, and did not increase the sizes of NRCs (P<0.05). ConclusionOur study discovered a possible novel pathway for Ang Ⅱ-induced cardiomyocyte hypertrophy through Rac1 activation-mediated upregulation of FGF13. |
| Key words: cardiomyocyte hypertrophy angiotensin Ⅱ Rac1 Rac1-V12 fibroblast growth factor 13 |
