[Protective effect of Icariin against TGF-β1-induced injury of rat Leydig cells].

Objective: To study the effect of Icariin on rat Leydig cells with TGF-β1-induced injury.

Methods: We determined the optimal concentration of Icariin for protecting primarily cultured Leydig cells against TGF-β1-induced injury by methyl thiazolyl tetrazolium assay. We detected the effects of Icariin on the secretion of estradiol (E2) and activity of aromatase in the injured Leydig cells by radioimmunoassay and Tritium water release experiment and its effect on the gap junctional intercellular communication (GJIC) between the Leydig cells by fluorescence distribution after photobleaching.

Results: Different concentrations of Icariin showed different degrees of protective effect on the TGF-β1-treated Leydig cells, the effect observed at 20 μg/ml and at its optimum at 160 μg/ml. After treatment of the injured Leydig cells with Icariin at 160 μg/ml, significant improvement was observed in the E2 secretion and aromatase activity (P<0.01) as well as in the GJIC between the Leydig cells (P<0.01).

Conclusions: Icariin can effectively protect rat Leydig cells against TGF-β1-induced injury, which is largely attributed to its effects of increasing E2 synthesis, enhancing aromatase activity, and improving GJIC between Leydig cells.