鸢尾素改善肝脏脂质代谢紊乱减轻非酒精性脂肪性肝病的研究现状

Research Status of Irisin in Improving Hepatic Lipid Metabolism Disorder and Reducing NAFLD

肝脏大量脂质蓄积是非酒精性脂肪性肝病(nonalcoholic fatty liver disease,NAFLD)的重要病理特征。肝脏脂质摄取、脂质从头合成、脂肪酸氧化分解和脂质分泌输出这4个环节间的失衡是造成肝脏脂质蓄积的重要原因。运动具有改善脂质代谢,缓解NAFLD发展的作用,但其机制复杂尚未完全阐明。肌肉不仅是运动器官,还是重要的内分泌器官,一系列介导运动促进健康效应的内分泌因子主要由肌肉产生。鸢尾素(Irisin)是主要由肌肉分泌的内分泌因子,其合成和分泌受运动调节,可靶向机体多种器官组织,发挥改善NAFLD等肥胖相关慢性代谢性疾病的作用。Irisin改善NAFLD的效应与其对脂质代谢的积极调控作用密不可分。本文阐述了运动调控Irisin合成与分泌的可能机制,并对Irisin改善上述4个肝脏脂质代谢的重要环节、减轻NAFLD的研究进展进行了总结,同时提出其中尚需进一步明确的问题,以期更好地理解Irisin介导运动在NAFLD等代谢疾病中的作用。

Nonalcoholic fatty liver disease(NAFLD)does great harm to human health,and the incidence is increasing year by year.The liver serves an important role in lipid metabolism.Hepatic steatosis develops as a consequence of lipid metabolic dysregulation,namely the imbalance among fatty acid uptake,de novo lipogenesis(DNL),fatty acid oxidation(FAO)and very low density lipoprotein-mediated lipid export.With diverse healthpromoting effects,exercise is a cheap and effective intervention for the prevention and treatment of NAFLD.Amelioration of impaired lipid metabolism acts as an important mechanism by which exercise protects against NAFLD.However,how exercise ameliorates lipid metabolic dysregulation is still unclear.Skeletal muscle is not only a vital organ of motion,but also has an endocrine function,it secretes numerous myokines which mediates exercise-induced benefits on our body.Irisin is a small peptide derived from proteolytic cleavage of fibronectin type III domain containing protein 5(FNDC5).As a myokine,its production is regulated by exercise and it play an important role in exercise-induced protection against obesity-related chronic diseases,such as NAFLD.A growing body of research has demonstrated that Irisin ameliorates lipid metabolic dysregulation in NAFLD.Irisin mediated inhibition of hepatic DNL and FAO has been reported.However,the effect of Irisin on fatty acid uptake and lipid export is still unknown.In the present review,we summarized the researches focusing on how exercise regulated Irisin production and the effect of Irisin on lipid metabolism on NAFLD.To clarify the above problems will help us to better understand the role of Irisin on exercise-mediated protection against NAFLD.