Non-alcoholic fatty liver disease (NAFLD) is a chronic disease affecting up to 25% of the population worldwide. n-3 long-chain polyunsaturated fatty acids (n-3 PUFA) have been associated with improved clinical parameters of NAFLD. Our purpose was to conduct a pilot study to evaluate the effects of n-3 PUFA supplementation in a randomized, double-blind, placebo-controlled clinical study performed on NAFLD individuals diagnosed by ultrasound. Patients received n-3 PUFA (n = 13) or placebo (n = 11) supplementation for six months. Circulating miR-122 expression (determined by quantitative real time-polymerase chain reaction (qRT-PCR), liver fibrosis (FibroScan^®), red blood cells (RBC) fatty acids (gas chromatography), and biochemical tests were performed at baseline and after intervention. After the intervention, in the n-3 PUFA group, docosahexaenoic acid (DHA) and omega index increased significantly in RBC (p = 0.022 and p = 0.012, respectively), in addition to a significant reduction in alkaline phosphatase (ALP) (p = 0.002) and liver fibrosis (p = 0.039). However, there was no change in the expression of circulating miR-122 in both groups. Our results showed that omega-3 PUFA were incorporated in erythrocytes after six months of fish oil supplementary intake, and that n-3 PUFA were effective in reducing ALP and liver fibrosis without altering the expression of circulating miR-122 in individuals with NAFLD.

Changes in lipid metabolism occur during the development and progression non-alcoholic fatty liver disease (NAFLD). However, the fatty acid (FA) profile in red blood cells (RBC) from patients with liver fibrosis remains unexplored. Thus, the goal of this study was to evaluate the fatty acid profile in RBC, dietary lipid intake and insulin resistance indicators in patients with NAFLD, according to the degree of hepatic fibrosis. Using elastography, patients were classified with (n = 52) and without (n = 37) advanced liver fibrosis. The fatty acid profile in RBC was analyzed using gas chromatography and the lipid intake was evaluated through a 24-h dietary recall. Subjects with advanced liver fibrosis had higher levels of palmitic, stearic and oleic acid and total monounsaturated fatty acid (MUFA) and insulin (p < 0.05), and lower levels of elongase very long chain fatty acids protein-6 and the delta-5-desaturase enzymatic activity (p < 0.05). These results suggest a lack of regulation of enzymes related to FA metabolism in patients with advanced fibrosis.