Effects of long-term dietary zinc manipulation on diabetic indices and fatty acid composition of adipose tissue phospholipid and triglyceride of diet-induced obese C57BL/6J mice
Tallman, Diana L.
Obesity is powerful predictor of insulin resistance and a major risk factor for Diabetes Mellitus Type 2 (DM2) in susceptible humans and rodent models. Dietary zinc deficiency has several characteristics common to DM2, but no information exists identifying the impact of altered dietary zinc status on the development of specific traits in diet-induced obesity and diabetes. Therefore, the objective of this experiment was to investigate the effects of zinc deficiency and supplementation on diabetic indicators and adipose tissue fatty acid composition using a diet-induced model of obesity and DM2 in C57BL/6J mice. Weanling C57BL/6J mice were randomized to diets containing 16% calories as soybean oil (SO) or 55% calories as mixed fat (MF) for 16 weeks. The SO and MF groups were further randomized to either a marginally zinc deficient (ZD, 3 ppm Zn), zinc control (ZC, 30 ppm Zn), or zinc supplemented (ZS, 150 ppm Zn) diet. The study was unable to induce obesity and diabetes in C57BL/6J mice by alteration of the dietary fatty acid composition and fat content, but it did identify obesity-prone mice fed the SO and MF diets. Dietary fat, but not dietary zinc, altered the fatty acid composition of adipose tissue phospholipid and triglyceride. (Abstract shortened by UMI.)