Effect of supplementation with gamma-linolenic acid on the fatty acid composition of lipids from the liver and plasma in the diabetic rat

Abstract

The main difference between normal and streptozotocic rat fed a diet, supplied during 35 days, including (as 1.5 g oil for 100 g diet) either naudicelle oil (with gamma-linolenic acid), either sunflower oil (without gamma-linolenic acid), or naudicelle oil + peanut oil, is that there are more non esterified fatty acids in streptozotocic livers. This result supports the view that liver phospholipids are more labile or that there is an important release of fat, even if we do not observe an increase of streptozotocic rat plasmatic non esterified fatty acids. Comparing normal and streptozotocic rat we found interesting results about fatty acids liver lipids composition: non esterified fatty acids are particularly rich in polyunsaturated fatty acids, mainly in linoleic and arachidonic acids, in diabetic rat. These results contribute to explain, to some extent, the important catabolism of polyunsaturated fatty acids in the diabetic rat, as they may reveal an increased activity of phospholipase A2 in this kind of animal. Naudicelle oil in the diet is, in our experiment, without favourable results on the amount of different lipidic classes and their fatty-acids composition, into liver and plasma of the streptozotocic rat, comparatively to the rat administered with sunflower oil; this may be explain by the fact that gamma-linolenic acid was in restricted amount in the diet and that its own conversion was partially inhibited by diabetes.