Dietary cholesterol-fat type combinations and carbohydrate and lipid metabolism in rats and mice

In rats fed semipurified cholesterol-free diets, dietary corn oil induced higher levels of liver cholesterol, but lower concentrations of plasma cholesterol, plasma triglycerides and blood D-3-hydroxybutyric acid, than did coconut fat. Addition of cholesterol to the diets (1%, w/w) greatly increased liver cholesterol levels but did not affect the corn oil effect upon liver and plasma cholesterol. In contrast, dietary cholesterol prevented the corn oil effects upon plasma triglycerides and blood D-3-hydroxybutyric acid. Liver glycogen levels in rats increased significantly after cholesterol feeding, the effect being independent of dietary fat type. In mice, dietary corn oil, compared to coconut fat, elevated liver cholesterol only when the diet contained cholesterol. Corn oil caused an increase of liver glycogen in mice in the presence, but not in the absence of dietary cholesterol. This study shows that dietary cholesterol-fat type combinations influence various aspects of lipid and carbohydrate metabolism in rats and mice.