鸢尾素对脓毒症引发的急性肺损伤的影响及机制

Protective mechanism of Irisin in sepsis-induced acute lung injury

目的探究鸢尾素(Irisin)在脓毒症(sepsis)诱导的急性肺损伤(acute lung injury,ALI)中的作用机制。方法将C57小鼠以随机数字表法分为对照(Con)组、鸢尾素(Irisin)组、盲肠结扎(cecal ligation and puncture,CLP)组、CLP-Irisin组。将A549细胞分为对照(PBS)组、脂多糖(lipopolysaccharide,LPS)组、Irisin保护组(LPSIrisin)、LPS-Irisin-尿石素A(urolithin A,UA)组、LPS-UA组、LPS-3-甲基腺嘌呤(3-Methyladenine,3-MA)组。以CCK-8试剂盒检测细胞活力、并检测MPO、PaO_(2)/FiO_(2)、IL-1α、IL-6、TNF-α、H_(2)O_(2)、MDA、GSH-Px活力等,同时以Western blot方法分析线粒体自噬相关蛋白的表达情况。结果在体研究表明,Irisin可通过调节线粒体自噬并降低肺组织炎性因子表达(P<0.05)与抑制氧化应激(P<0.05),增加氧合指数并降低小鼠死亡率,进而缓解脓毒症导致的ALI。体外研究证实,LPS可显著降低A549细胞活力(P<0.05),同时炎性因子表达增加与线粒体自噬异常。进一步的研究证实,Irisin处理可显著缓解LPS诱导的细胞损伤(P<0.05),而Urolithin A处理则部分抵消Irisin对细胞的保护作用(P<0.05)。结论Irisin通过调节Pink1/Parkin介导的线粒体自噬,维持线粒体功能,缓解脓毒症导致的ALI。

AIM To explore the mechanism of Irisin in sepsis-induced acute lung injury(ALI).METHODS C57 mice were randomly divided into Con group,Irisin group,CLP Group and CLP-Irisin group.A549 cells were divided into Con group,LPS group,Irisin group(LPS-Irisin),LPS-Irisin-UA group,LPS-UA group and 3-MA group.CCK-8 kit was used to detect cell viability,MPO,PaO_(2)/FiO_(2),IL-1α,IL-6,TNF-α,H_(2)O_(2),MDA and GSH-Px activity and Western blot was used to analyze the expression of mitophagy related proteins.RESULTS In vivo studies showed that Irisin alleviated sepsis-induced ALI by regulating mitophagy and reducing the expression of inflammatory factors in lung tissues(P<0.05).Meanwhile,the oxygen index was increased and the mortality rate of mice was decreased.In addition,Irisin resisted CLP-induced ALI by reducing oxidative stress(P<0.05).In vitro studies confirmed that LPS significantly reduced the viability of A549 cells and increased the expression of inflammatory factors and abnormal mitophagy(P<0.05).Irisin or 3-MA treatment significantly reduced LPS induced cell injury and UA treatment partially counteracted the protective effect of Irisin on A549 cells(P<0.05).CONCLUSION Irisin alleviates sepsis-induced ALI by regulating Pink1/Parkin mediated mitophagy and maintaining mitochondrial functions.