Effects of Lycium barbarum polysaccharides on the proliferation and differentiation of primary Sertoli cells in young rats

Sertoli cells (SCs) provide physical support and material supply for germ cells and participate in the formation of blood-testis barrier. The number of SCs is directly proportional to the number of germ cells. And mature SCs ensure the growth of germ cells and the production of sperm. In this study, we explored the effect and underlying mechanism of Lycium barbarum polysaccharides (LBP) on primary SCs in young rats. Primary SCs were isolated from the testis of 20-day old rats. The cells were then treated with different concentrations of LBP. Immunocytochemistry was used to detect the expression of Ki67 and the androgen receptor (AR), and western blotting was used to detect the expression of cytokeratin-18 (CK-18), AR and phosphorylated Akt (Ser473) in SCs. The number of SCs increased significantly after LBP treatment, and the 100 mg/mL. LBP group had 14% more cells than the control group. The expression of Ki67 in LBP treated groups also increased significantly. LBP inhibited the expression of cytokeratin 18 in SCs. Besides, LBP increased the expression of AR on SCs and promoted the activation of Akt at the ser473 phosphorylation site. LBP promotes the proliferation of immature SCs in young rats and also accelerates their differentiation and maturation. This seems to be associated with activation of the Akt signaling pathway via up-regulation of AR.