Liver fibrosis in the context of nonalcoholic steatohepatitis: the role of adipokines.

Liver fibrosis is a multifaceted process that occurs as a consequence of chronic liver injury. This process is characterized by inflammation, activation of matrix-producing cells, matrix deposition and remodeling, and epithelial cell regeneration. In subjects with chronic liver damage, fibrogenesis is favored by the presence of obesity and insulin resistance, which are also relevant risk factors for the development and progression of nonalcoholic steatohepatitis (NASH). It is now well-known that adipose tissue is not only involved in energy storage but also functions as an endocrine organ that secretes various bioactive substances known as adipokines. This term identifies a group of polypeptide molecules, which exert local, peripheral and/or central actions. Additionally to their well-established role in controlling adipose tissue physiology, energy homeostasis, inflammation and immune function, adipokines have been shown to be involved in different obesity-related diseases, such as hypertension, atherosclerosis and type 2 diabetes. In liver diseases, the biologic actions of these factors may contribute to the mechanisms leading to NASH. In this review, we focus on the role of adipokines in liver fibrogenesis and discuss their potential as regulators of this pathological condition and as targets for future pharmacological treatment strategies of chronic liver diseases.