Gestational diabetes is unique because of the diversity of problems that can affect the embryo/fetus beginning with conception. Streptozotocin (STZ), a diabetogenic agent when administered to pregnant rats in high dose, induces diabetes by destructing pancreatic β-islet cells resultantly in the intrauterine life of developing fetuses limits their adaptation with depleted insulin secretion. Similarly, environmental stressors like cold-stress result in fetal hypoinsulinemia with a reduction in the number of insulin receptors on target cells. In a given situation, if both stressors are prevailing, the resultant free radical production in prenatal life may bring severe oxidative stress on the molecular integrity of proteins that might progress to weaning and adulthood. In this study, the oxidative indices measured in STZ induced gestational rats upon exposure to cold stress (15°C & 20°C) indicate significant changes in discrete brain regions. Cold-stress found to exacerbate the free radical production in diabetic subjects and impose a higher rate of protein oxidation confirming synergetic effects. The findings for the first time confirm that the oxidative changes that occurred due to prenatal stress remain into weaning and adulthood, specifically in the functional areas like the cerebral cortex and hippocampus, which in turn may bring impairments/deficits in memory and cognitive processes.

Keywords : Gestational diabetes, Cold stress, Developing brain, Free-radicals, Protein oxidation, Synergistic effects.