Research progress of the role of complement system in nonalcoholic fatty liver diseases

Nonalcoholic fatty liver diseases (NAFLD) have now become an important cause of chronic liver diseases in developed countries, its morbidity in China has been up to 15%, and it’s been increasing year by year. Although the pathogenesis of NAFLD is not completely understood, obesity, insulin resistance and lipid metabolism disorder are implicated. As an essential part of the immune system, complement system also participates in metabolic regulation. In particular, the activation of alternative complement pathway and the metabolites, such as C3a, C5a and C3a-desArg (ASP) are significantly related to insulin resistance, lipid metabolism disorder and hepatocellular inflammatory injury. In this paper, we aim to summarize the research progress of the role of complement system in NAFLD. Key words: Nonalcoholic fatty liver diseases; Complement system; Insulin resistance; Lipid metabolism disorder