Effects of n-3 polyunsaturated fatty acids in subjects with nonalcoholic fatty liver disease

BACKGROUND:Long-chain polyunsaturated fatty acid omega-3 levels are decreased in the hepatic tissue of patients with nonalcoholic fatty liver disease. Polyunsaturated fatty acids are negative regulators of hepatic lipogenesis and attenuate the inflammatory response in mice.AIM:To investigate whether polyunsaturated fatty acid may be effective in the treatment of nonalcoholic fatty liver disease.METHODS:Forty patients with nonalcoholic fatty liver disease were randomized into two groups for treatment of 6 months duration. Group DP (n=20) received an AHA recommended diet and polyunsaturated fatty acid 2g/day; Group D (n=20) received only the AHA regular diet. Outcome measurements were fatty liver assessed by abdominal ultrasound, liver aminotransferase and tumour necrosis factor-alpha serum levels, and insulin resistance assessed by HOMA(IR).RESULTS:After 6 months of treatment, the DP group displayed a decrease in alanine aminotransferase levels (p<0.01), as well as in triglyceride levels (p<0.01), serum tumour necrosis factor-alpha levels (p<0.05) and in HOMA(IR) (p<0.05). In the D group, no significant modification was observed. In the DP group, complete fatty liver regression was observed in 33.4% of the patients, and an overall reduction in 50%. In contrast, no patient achieved complete regression in the D group, whereas some amount of reduction occurred in 27.7% of the patients; the remaining 72.2% did not change.CONCLUSION:Our results indicate that alanine aminotransferase, triglyceride and serum tumour necrosis factor-alpha levels, as well as fatty liver improved after polyunsaturated fatty acid administration.