沉默信息调控因子1通路介导补骨脂酚抑制脂多糖诱导的乳鼠心肌细胞炎症反应及凋亡

Bakuchiol ameliorates LPS-induced cardiomyocyte inflammation and apoptosis via SIRT1 pathway

目的研究补骨脂酚(BAK)对脂多糖(LPS)诱导的SD乳鼠心肌细胞炎症反应模型的作用及其分子机制。方法SD乳鼠心肌细胞经1μM、5μM或10μM的BAK孵育4 h后,再用LPS(100 ng/ml)孵育12 h,造成炎性心肌细胞损伤。用CCK8法检测心肌细胞活力,TUNEL法检测心肌细胞凋亡水平。ELISA法检测培养基中炎性因子TNF-α和IL-1水平,Western-blot法检测SIRT1、Bax和Bcl-2的表达水平。使用沉默信息调控因子1(SIRT1)阻断剂EX527观察SIRT1信号通路在这一过程中的作用。结果 LPS处理可以诱导心肌细胞炎性因子肿瘤坏死因子-α和白介素-1释放(P<0.05 vs control组),降低心肌细胞活力并促进其凋亡。蛋白水平抑制SIRT1表达,Bcl2下调,Bax上调(P<0.05 vs control组)。1μM、5μM和10μM的BAK预孵育可浓度依赖性地抑制炎性因子释放、改善心肌细胞活力、上调SIRT1表达,提高Bcl2并降低Bax表达,抑制心肌细胞凋亡。SIRT1阻断剂EX527可显著抑制上述抗炎及抗凋亡作用。结论 BAK通过激活SIRT1信号通路,减轻LPS诱导的大鼠心肌细胞炎症反应。

Objective To investigate whether BAK exerts an effect on LPS-induced cardiomyocyte inflammation and the mechanisms involved.Methods Neonatal rat ventricular myocytes （NRVMs） were pretreated with BAK in three dose （1/5/10 μM） for 4hours and then subjected to LPS stimulation （100 ng/ml,12 hours）.CCK-8 kits were used to measure cell viability.To analyze cardiomyocyte apoptosis,TUNEL assay was performed.ELISA kits were used to measure TNF-α IL-1 and the expression of SIRT1,Bcl2 and Bax were evaluated by western blotting.The specific inhibitor of SIRT1,EX527 were used to investigate roles of SIRT1 in this process.Results LPS administration could induce the release of inflammation factors （TNF-α IL-1） and LDH1 in neonatal rat ventricular myocytes （NRVMs）.Lower cell viability and more apoptosis were observed.Decreased SIRT1 was observed in LPS-induced inflammation （P〈0.05,vs control group）.After administration of BAK,as demonstrated by dose-independent decreases of TNF-α IL-1 and LDH1 cell viability increased while less apoptosis was observed.Western blot analysis showed an upregulation of SIRT1 and Bcl2/Bax ratio.EX527 reversed the anti-inflammatory function of BAK.Conclusion BAK pretreatment may prevent LPS induced inflammation and reduce cardiomyocyte apoptosis via SIRT1 signaling pathway in myocytes.