Protective effect of swimming and genistein on the expression of microRNA 132, insulin growth factor 1, and brain-derived neurotrophic factor genes, as well as spatial memory, in the hippocampus of diabetic ovariectomized rats

The present study aimed to assess the effects of the combined use of exercise and genistein on the hippocampal expression of microRNA-132, IGF-1, and BDNF in type 2 diabetic ovariectomized rats.

Wistar female rats in the weight range of 180-220 gr (n=10) were assigned to six groups: sham, ovariectomy, ovariectomized diabetic, ovariectomized diabetic treated with genistein for eight weeks, diabetic ovariectomized treated with swimming for eight weeks, and a group that was treated with both genistein and swimming for eight weeks. The effect of those treatments was assessed by the determination of microRNA-132, insulin growth factor 1 (IGF-1), and brain-derived neurotrophic factor (BDNF) expression levels within the hippocampus. These genes were evaluated by real-time-polymerase chain reaction (RT-PCR) and spatial memory was assessed by the Morris water maze.

Ovariectomy demonstrated a decrease in the expression of microRNA-132, IGF-1, and BDNF in the hippocampus, as well as spatial memory, in diabetic ovariectomized rats, which showed a  greater reduction in the expression of those genes in rats (P<0.05). Nevertheless, genistein administration, swimming training, and a combination of them significantly up-regulated microRNA-132, BDNF, and IGF-1 expression, as well as spatial memory (P<0.05).

As evidenced by the obtained results, the combined use of genistein and swimming could prevent estrogen deficiency effects in the hippocampus of ovariectomized diabetic rats