Key points of etiopathogenesis of non-alcoholic fatty liver disease

Based on the analysis of Russian and foreign literature sources, the definition of non-alcoholic fatty liver disease is given, modern data on the etiology, prevalence, risk factors for the development and progression of non-alcoholic fatty liver disease are presented. Nonalcoholic fatty liver disease found in at least a quarter of the world’s population and the main target of this disease is the most able-bodied and economically active part of the population. These circumstances give this problem special medical, social and humanitarian significance. Two different pathomorphological states represent non-alcoholic fatty liver disease: nonalcoholic fatty liver and nonalcoholic steatohepatitis, which, in turn, includes liver fibrosis, liver cirrhosis, and hepatocellular carcinoma. Non-alcoholic fatty liver disease is determined not only on the basis of the results of histological studies in the presence of steatosis in more than 5% of hepatocytes, but also in excess of proton density of more than 5.6% during proton magnetic resonance spectroscopy, or when performing selective magnetic resonance imaging with quantitative determination of fat and water. Modern data on the pathogenesis of nonalcoholic fatty liver disease are presented. Attention is focused on such key mechanisms in the development of the disease as insulin resistance, lipotoxicy, oxidative stress, systemic aseptic inflammation, mitochondrial dysfunction and endoplasmic reticulum, which served as the basis of the pathogenetic theory of «multi hit». The pathogenesis of nonalcoholic fatty liver disease plays an important role visceral adipose tissue, which also synthesized proinflammatory cytokines and adipokines, as well as the syndrome of excessive bacterial growth, due to the formation of endotoxemia and atherogenic dyslipidemia.