Features of a necrotic and inflammatory process in different forms of nonalcoholic fatty liver disease

Aim. To identify the features of development of a necrotic and inflammatory process in different forms of nonalcoholic fatty liver disease (NAFLD), by comparatively analyzing a full set of clinical and laboratory parameters, including the cytokine status and the expression level of enzyme genes controlling the apoptosis of peripheral leukocytes. Subjects and methods 86 patients with NAFLD, including 8 (9.3%) with hepatic steatosis (HS), 70 (81.4%) with nonalcoholic steatohepatitis (NASH), 40, 19, and 11 with mild, moderate, and high disease activity, respectively, and 8 (9.3%) with liver cirrhosis (LC), were examined. A control group consisted of 34 healthy donors. Clinical and biochemical blood indices, cytokine profile, and the level of caspase gene transcripts in the peripheral blood leukocytes (PBL) were estimated. Results. As compared to the controls, the patients with HS had higher tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) levels and lower caspase 3, 6, and 8 mRNA in PBL. The concentration of IL-10 in NASH was higher than that in steatosis and positively correlated with the level of proinflammatory cytokines. The levels of TNF-α and IL6 were higher in the patients with NASH than in the controls. Those of C-reactive protein, γ-globulin, IL-6, and cytokeratin-18 fragment increased with the progression of NASH. In the latter, the transcriptional activity of caspase-3 gene decreased relative to the reference value and negatively correlated with the level of proinflammatory cytokines. In the patients with LC, the gene expression profile of caspases in PBL was similar to that in the control group; the level of IL-6 was higher than that in steatosis and NASH, that of IL-1β was higher than in HS and positively correlated the concentration of IL-6 and the activity of alanine aminotransferase and aspartate aminotransferase. Conclusion. The features of a necrotic and inflammatory process were identified in different forms of NAFLD. When the latter progressed, the cytokine profile and gene expression levels of caspases in PBL altered along with a change in the general clinical picture.

non-alcoholic fatty liver disease, steatosis, nonalcoholic steatohepatitis, liver cirrhosis, inflammation, cytokines, caspases, apoptosis