The effect of voluntary exrcise on the permeability of the blood-testis barrier and the expression levels of tight junction proteins in the testis of the diabetic and non-diabetic male rats

Abstract

Aims and Objective: Diabetes is a complex heterogeneous disease and can lead to infertility in affected men. Considering the preventive and protective role of voluntary exercise, this study investigated the effect of voluntary exercise on the permeability of blood – testis barrier and it’s proteins levels in type 2 diabetic male rats. Methods and materials: In this study, 64 male Wistar rats (180-220 gram) were used. The rats were randomly divided into 8 groups: control (C), voluntary exercise (Ex), diabetes (D), high-fat diet (HFD), diabetes-voluntary exercise (D-Ex), high-fat diet-voluntary exercise (HFD- Ex), diabetes-high-fat diet (D-HFD), and diabetes-high-fat diet- voluntary exercise (D-HFD-Ex) groups. T2DM was induced by a high-fat diet regimen for four weeks followed by an intraperitoneal injection of streptozotocin (35 mg/kg) . Voluntary exercise was performed by placing the animals in cages equipped with a rotating wheel for 10 weeks. After completing all the interventions, the testicular proteins level of Claudin-3, Claudin-11, Occludens-ZO-1 were measured using western blot method. In addition, the permeability of the blood-testis barrier in the testicular tissue after FITC injection, cryosectioning and DAPI staining was evaluated using light microscopy. Results: High-fat diet and diabetes caused loss of BTB integrity and disrupted the balance testis proteins. Also, caused a significant decrease in the expression of blood barrier- testis proteins (zonula occludin-1, claudin 3 and claudin 11) and increased its permeability. Voluntary exercise recovered the integrity of the blood-testis barrier and the balance between ZO-1, Claudin3, 11 proteins . It ultimately caused a decrease in permeability and an increase in the expression of ZO-1, Claudin3, Claudin11 proteins and a significant improvement in the pathological indicators in the testicular tissue. Diabetes and high-fat diet lead to a decrease in the ZO-1, Claudin-3 and Claudin-11 proteins levels, the loss of integrity and increasement the permeability of the blood-testis barrier in the testes of diabetic and receiving high-fat diet rats. Voluntary exercise increased the of ZO-1, Claudin-3 and Claudin-11 proteins levels , improved blood- testis barrier integrity, and decreased the permeability of the blood-testis barrier in the testes of diabetic receiving a high-fat diet rats.