Effects of a Diet Supplemented with Fruit Antioxidants (Mango) on the Expression of K_ir6.2 (KCNJ11) in the Hippocampus and Kidney of Diabetic Rats

Diabetes induces inflammation in the brain and kidneys; it is also known to be linked with changes in the expression and functionality of K_ir channels. Diets rich in antioxidants (e.g., phenolic compounds) tend to reduce diabetes-related oxidative damage in several organs and the expression of K⁺ channels. We evaluated the effect of a diet supplemented with mango cv. ‘Ataulfo’ pulp and peel on the expression of the genes of K⁺ channels in the brain (hippocampus) and kidney of diabetic rats. Groups of experimental (streptozotocin, STZ-induced diabetes) male Wistar rats were fed with a diet supplemented with mango cv. ‘Ataulfo’ to evaluate, through end-point and quantitative PCR, what K⁺ channel genes change their expression in the hippocampus and kidneys. We found that mango supplementation produced significant differences in the relative mRNA expression of K_ir6.2 (KCNJ11) in both tissues. In the kidney, the expression increased significantly, while in the hippocampus, mango supplementation decreased or increased it depending on when supplementation began, before or after diabetes was induced, respectively. Thus, mango supplementation in this diabetes model exerted significant qualitative and quantitative changes to the expression of K⁺ channels’ genes in the hippocampus and kidneys of rats with streptozotocin-induced diabetes.