Role of the endocrine system in the pathogenesis of non-alcoholic fatty liver disease

Abstract

The most frequent liver disorder in metabolic syndrome is the nonalcoholic fatty liver disease. Its pathogenesis is a complex, multifactorial process, characterized by insulin resistance and involvement of the endocrine system. Hypothyroidism may lead to nonalcoholic steatohepatitis via hyperlipidemia and obesity. Adult patients with growth hormone deficiency have a metabolic syndrome-like phenotype with obesity and many characteristic metabolic alterations. The chronic activation of the hypothalamic-pituitary-adrenal axis results in metabolic syndrome as well. Cushing’s syndrome has also features of metabolic syndrome. Mild elevation of transaminase activities is commonly seen in patients with adrenal failure. Non-alcoholic steatosis is twice as common in postmenopusal as in premenopausal women and hormonal replacement therapy decreases the risk of steatosis. Insulin resistance, diabetes mellitus type 2, sleeping apnoe syndrome, cardiovascular disorders and non-alcoholic fatty liver disease are more frequent in polycystic ovary syndrome. Hypoandrogenism in males and hyperandrogenism in females may lead to fatty liver via obesity and insulin resistance. Adipokines (leptin, acylation stimulating protein, adiponectin) have a potential role in the pathogenesis of nonalcoholic fatty liver. The alterations of endocrine system must be considered in the background of cryptogenic liver diseases. The endocrine perspective may help the therapeutic approaches in the future.