Dietary Fat and the Inhibition of Hepatic Lipogenesis in the Mouse

Abstract

We have examined the effects of dietary fat upon lipogenesis from 1-¹⁴C-acetate by slices of mouse liver, under two sets of conditions: a) a high fat diet (15% corn oil) was fed for 1 to 5 days, following zero, 1 and 2 days of fasting; and b) corn oil, safflower oil, coconut oil, tricaprylin, tripalmitin, triolein, oleic acid and mineral oil (all at 10% of the diet) were fed for 3 days, with no prior fasting. Of the high fat diets only those high in linoleic acid suppressed fatty acid synthesis. Corn oil reduced fatty acid synthesis in nonfasted mice, and suppressed the usual “adaptive hyperlipogenesis” found after fasting and refeeding. From this work, and that of others, it is now clear that any alteration in hepatic lipogenesis induced by the inclusion of fat in the diet will depend not only on the fatty acid composition of the fat, but also on the level in the diet, the length of time it is fed, the animal species and age examined, and on whether the studies are conducted in vivo or in vitro.