Dietary carbohydrate influences tissue fatty acid and lipid composition in the copper-deficient rat

Fructose and copper have been shown independently to influence long chain fatty acid metabolism. Since fructose feeding exacerbates copper deficiency, their possible interaction with respect to tissue long chain fatty acid and lipid composition was studied. Weanling male Sprague-Dawley rats were given diets containing 0.6 or 6 mg/kg copper. The carbohydrate source (627 g/kg) was either fructose or corn starch. After 3 wk, fatty acid profiles and total lipids in heart and liver were analyzed. Copper-deficient rats fed fructose had more severe signs of copper deficiency than those fed starch, according to heart/body wt ratio, hematocrit, and liver copper content. The fatty acid composition of heart and liver triacylglycerol was significantly different between groups, but the changes did not correlate with the severity of copper deficiency. In heart, phosphatidylinositol and phosphatidylserine, arachidonic acid and docosapentaenoic acid (n-6) were increased 193 and 217%, respectively, p<0.05) in rats given the copper-deficient diet containing fructose. Changes in the long chain fatty acids in heart phospholipids may be related to the higher mortality commonly observed in rats fed a copper-deficient diet containing fructose.