Impact of maternal chromium restriction on glucose tolerance, plasma insulin and oxidative stress in WNIN rat offspring.

Robust evidence suggests that nutritional insult during fetal development could program the offspring to glucose intolerance, impaired insulin response and insulin resistance (IR). Considering the importance of chromium (Cr) in maintaining carbohydrate metabolism, this study determined the effect of maternal Cr restriction (CrR) on glucose metabolism and plasma insulin in Wistar/NIN (WNIN) rat offspring and the associated biochemical and/or molecular mechanisms. Female, weanling WNIN rats received ad libitum for 12 weeks, a control diet or the same with 65% restriction of Cr and mated with control males. Some of the Cr-restricted dams were rehabilitated from conception or parturition and their pups weaned on to control diet. At the time of weaning, half of the Cr restricted offspring were rehabilitated to control diet while others continued on Cr-restricted diet. Maternal CrR increased fasting plasma glucose, fasting insulin, homeostasis model assessment of IR, and area under the curve of glucose and insulin during oral glucose tolerance test in the offspring. Expression and activity of rate-limiting enzymes of glucose metabolism were comparable among different groups and expression of genes involved in insulin secretion was increased albeit in male offspring whereas antioxidant enzyme activities were decreased in offspring of both genders. Rehabilitation, in general, corrected the changes albeit partially. Maternal dietary CrR induced IR, impaired glucose tolerance in WNIN rat offspring and was associated with increased oxidative stress, which may predispose them to type 2 diabetes in their later life.