Plasma polyunsaturated fatty acids in liver cirrhosis with or without chronic hepatic encephalopathy: a preliminary study.

Fatty acid levels (from C14:0 to C22:6n3) in plasma lipid fractions were prospectively studied in 11 cirrhotic patients with chronic hepatic encephalopathy and compared with those in 23 cirrhotic patients without chronic hepatic encephalopathy with similar age, sex distribution, and liver and nutritional status, and in 11 age- and sex-matched, healthy subjects. Plasma lipid fractions were separated by thin-layer chromatography and fatty acids were identified by capillary column gas-liquid chromatography. Total n6 polyunsaturated fatty acid plasma levels were lower in cirrhotic patients--with and without chronic hepatic encephalopathy--than in control subjects. In addition, arachidonic acid levels, both in total lipids and fractions, were lower in patients with than in those without chronic encephalopathy. On the other hand, a selective decrease of plasma docosahexaenoic acid (a major component of neuronal membranes) was observed in those patients with chronic encephalopathy as compared with both control and cirrhotic subjects without chronic encephalopathy. These findings may be due to various mechanisms. Differences in long-chain polyunsaturated fatty acid content in fish- and meat-restricted diets partly may account for these findings. However, it could be speculated that polyunsaturated fatty acid biosynthesis may be reduced further in patients with chronic hepatic encephalopathy because of either a decrease in portal essential fatty acid extraction in the postabsorptive phase due to portal-systemic shunting or to the effect of protein-restricted diets. Furthermore, the finding of low plasma docosahexaenoic acid in these patients raises the possibility that this deficiency might be an additional pathogenic factor in chronic hepatic encephalopathy.