抄録
Conscious young adult male rats were given total-parenteral nutrition (TPN) with or without a soybean fat emulsion for 4 days and those that did not receive the emulsion (fat-free TPN group) developed severe fatty liver with hyperglycemia,hyperinsulinemia,and hypotriglyceridemia.These disorders were improved by administering TPN supplemented with soybean fat,equivalent to 20% of total calories,with glucose correspondingly reduced.In the fat-free TPN group,the expression of sterol regulatory element binding protein 1c (SREBP1c),acetyl-CoA carboxylase (ACC),and fatty acid synthase (FAS) mRNAs in the liver were coordinately up-regulated,resulting in an increase in non-essential fatty acids and a decrease in essential fatty acids in the liver,due to the fat supply drying up.In contrast,expression of carnitine-palmitoyltransferase (CPT) 1a mRNA decreased.However,in the group given the fat emulsion in their TPN,the expressions of all of the above types of mRNA remained similar to those in an oral diet control group.
It appeared that the hyperinsulinemia following infusion of excess glucose had induced lipogenesis and a decrease in fatty acid β-oxidation in the liver and that these changes were prevented by supplementation of soybean fat equivalent to 20% of total calories (with a corresponding reduction in glucose).Therefore,it may be appropriate to routinely supplement fat-free TPN with soybean fat in the clinical situation,substituting it for part of the glucose.In addition,serum glucose and insulin levels should be monitored during TPN infusions.
