Abstract
In order to investigate the effect of inositol deficiency on hepatic lipid metabolism and lipoprotein secretion, gerbils were fed a high fat diet containing 15% coconut oil (COC) or safflower oil (SAF), or a low-fat, high carbohydrate diet containing 1% safflower oil (CHO) with or without 0.1% inositol for 3 to 5 weeks. Hepatic lipid accumulation and in vitro incorporation of [1-14C]acetate and [1-14C]oleic acid into hepatic lipids were measured in liver slices while the hepatic triglyceride secretion rate (lipoprotein secretion) was measured in vivo in fasting gerbils following Triton WR 1339 injection. Inositol-deficient gerbils accumulated more total hepatic lipid than the supplemented group independent of diet although coconut oil feeding alone exacerbated the lipid accumulation independent of inositol. Whereas inositol deficiency did not affect fatty acid esterification, it did result in a greater incorporation of [1-14C]acetate into hepatic lipids. In addition, the triglyceride secretion rate was significantly reduced in deficient gerbils. Thus, both inositol and saturation of the dietary fat influenced hepatic lipid accumulation which appeared to result primarily from an inadequate secretion of very low density lipoprotein.