Implications of Mitochondrial Unfolded Protein Response and Mitokines: A Perspective on Fatty Liver Diseases

The signaling network of the mitochondrial unfolded protein response (UPR(mt)) and mitohormesis is a retrograde signaling pathway through which mitochondria-to-nucleus communication occurs in organisms. Recently, it has been shown that the UPR(mt) is closely associated with metabolic disorders and conditions involving insulin resistance, such as alcoholic and non-alcoholic fatty liver and fibrotic liver disease. Scientific efforts to understand the UPR(mt) and mitohormesis, as well as to establish the mitochondrial proteome, have established the importance of mitochondrial quality control in the development and progression of metabolic liver diseases, including non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). In this review, we integrate and discuss the recent data from the literature on the UPR(mt) and mitohormesis in metabolic liver diseases, including NAFLD/NASH and fibrosis.