The fatty acid composition of serum phospholipid in liver diseases

Abstract

In chronic l iver diseases, we have observed a decreased linoleic and arachidonic acid levels accompanied by a increased level of oleic acid in the fat ty acid composit ion of serum phospholipid. Before and af ter adminis t ra t ion of ethyl linoleate to pa t ien ts with chronic l iver diseases, the fa t ty acid composition of se rum phospholipids was determined. After t r ea tment , linoleic acid level was found to be increased, oleie acid deceased, while arachidonic acid unchanged. These resu l t s suggest a dis turbance of arachidonic acid synthes is f rom Iinoteic acid. In l iver diseases prote in metabol ism is dis turbed. On the other hand prote in metabolism is believed to have a close in terre la t ionship with lipids metabolism. These facts lead to a suggestion tha t a abnormal i ty in essential fa t ty acid metabol ism may have relat ion wi th dis turbance of prote in synthesis . In rats , low protein with low linoleic acid diet for 4 weeks revealed a remarkable decrease of linoleic and arachidonic acid levels with increaeed levels of oleic and palmitoleic acid in l iver phospholipids. The t rea ted ra t s were divided into two groups. Low protein diet wi th high linoleic acid then was given to one group and to the other, high protein diet wi th high linoleic acid for two weeks, respectively. The linoleic, oleic and palmitoleic acid levels in the l iver phospholipids within normal range in both groups, the arachidonic acid level re turned to normal range in the la t ter group, whereas stayed lower in the former . These data suggests tha t the abnormal i ty in l iver protein metabol ism induced by low prote in diet has some influenced on essential fa t ty acid metabolism. In human liver diseases, disturbance of essential fa t ty acid metabol ism may have a close corre la t ion wi th the abnormal i ty in protein metabol ism.