Serum and erythrocyte membrane fatty acid levels may be used as biomarkers to assess the severity of NAFLD

The aim of this work is to study the possibility of using blood serum (BS) fatty acids (FA) and erythrocytes (ER) as diagnostic markers of the severity of NAFLD. Materials and methods. We examined 52 patients with NAFLD (51.8 ± 3.9 years), confirmed by the NLFS index, and 20 apparently healthy men (49.2 ± 4.5 years). The degree of liver fibrosis was established by indirect elastometry (FibroScan® 502 Echosens, France). 27 patients had an initial degree of fibrosis (F0-1), 25 had severe fibrosis (F2-4). The study of the composition of fatty acids of Er and BS was carried out using a GC / MS system based on three Agilent 7000B quadrupoles (USA). Results. Significant differences in the levels of fatty acids in blood serum and erythrocyte membranes in patients with NAFLD were revealed, associated with the degree of fibrosis and necroinflammatory activity. To distinguish between mild and severe fibrosis in NAFLD, the levels of saturated fatty acids (myristic, pentadecane, margarine) and omega-3 PUFAs (eicosapentaenoic, docosapentaenoic, docosahexaenoic) were found to be significant (p = 0.002-0.0003). Saturated and monounsaturated FAs (palmitelaidic, palmitoleic, vaccenic) played a key role in differentiating the degree of necroinflammatory activity (minimal versus pronounced) (p = 0.03-0.005). The created diagnostic panels (FA of blood serum and erythrocyte membranes) made it possible to differentiate patients with NAFLD with varying degrees of fibrosis. Correlations of FA levels in erythrocyte membranes and blood serum with manifestations of metabolic syndrome, indicators of liver damage in patients with NAFLD were revealed. Conclusions. The established differences in fatty acid profiles of blood serum and erythrocyte membranes in patients with NAFLD, associated with the degree of fibrosis, necroinflammatory activity, manifestations of metabolic syndrome and indicators of liver damage, should be considered as promising biomarkers for assessing the severity of NAFLD.