Treadmill exercise activates PI3K/Akt signaling pathway leading to GSK-3β inhibition in the social isolated rat pups

Abstract

Social isolation is known to precipitate depression-like symptoms in ro-dents and has emerged as a dependable paradigm to screen the be-havioral and neurobiological changes observed in humans. In the pres-ent study, the undying mechanisms of treadmill exercise on social isola-tion-induced depression was evaluated. The rat pups in the social iso-lation groups were housed individually. The social isolation procedures started on the postnatal day 14. The rat pups in the exercise groups were forced to run on treadmill for 30 min once a day from postnatal day 21 to postnatal day 34. The expression of phosphoinositide 3 kinase (PI3K), tyrosine kinase B (Akt), and glycogen synthase kinase 3β (GSK-3β) in the hippocampus were determined by using western blot analy-sis. The ratio phosphorylated PI3K (p-PI3K)/PI3K and phosphorylated Akt (p-Akt)/Akt were decreased and the ratio of phosphorylated-GSK-3 (p-GSK-3β)/GSK-3β was increased by social isolation. Treadmill exer-cise increased the ratio p-PI3K/PI3K and p-Akt/Akt and suppressed the ratio of p-GSK-3β/GSK-3β in the hippocampus of social isolated rat pups. Treadmill exercise activates PI3K/Akt signaling pathway leading to GSK-3β inhibition in social isolated rats. These results suggested that tread-mill exercise may improve depressive symptoms via activation of PI3K/Akt signaling pathway.