Gender, Dietary Copper and Carbohydrate Source Influence Cardiac Collagen and Lysyl Oxidase in Weanling Rats

Abstract

The present investigation was conducted to determine the effects of consumption of diets containing fructose or cornstarch on cardiac collagen metabolism in weanling male and female rats fed copper-deficient or copper-adequate diets for 5 wk. Although both male and female rats that consumed the copper-deficient diet containing fructose were similarly copper deficient, only the males showed severe cardiac pathologies and two died prematurely due to heart-related abnormalities. These pathologies were accompanied by a significant reduction of cardiac lysyl oxidase activity and elevated soluble and total cardiac collagen concentrations compared with rats fed copper-adequate diets. These abnormalities were less severe in copper-deficient rats fed cornstarch. The data show that the activity of the copper-containing enzyme lysyl oxidase is affected by both dietary carbohydrate and gender. The pathologies of heart tissue could be the result of abnormal crosslinking of collagen induced by the combination of copper deficiency, fructose feeding and the sex of the rats.