Effect of visfatin on testicular steroidogenesis in purified Leydig cells
Background:
Lower testosterone levels have been reported in men suffering from diabetes mellitus. Men with insulin resistance states such as obesity and type 2 diabetes mellitus have significantly lower testosterone levels than age-matched normal weight and non-diabetic controls. Adipose tissue secretes variety of adipokinesincluding adiponectin, resistin, visfatin, TNF-alpha. The study was designed to study the effect of visfatin on testicular steroidogenesis in purified Leydig cell in vitro.
Methods:
Leydig cells of Sprague Dawley rats were isolated and purified by Percoll. Cells were incubated for 3 hours with/without visfatin in the presence/absence of LH and intracellular signalling blockers including PKC blocker, PKA blocker and Raf1/Ras blocker. Cell culture extracts were stored at -80 before analysis for levels of testosterone hormone by ELISA.
Results:
Visfatin increased testosterone production (p < 0.001) from cultured Leydig cells. Raf1/Ras blocker decreased visfatin induced steroidogenesis (p < 0.001).
Conclusion:
Visfatin increased testicular steroidogenesis from Leydig cells in vitro models and operates through variety of enzymes, but especially through Ras/Raf1 kinase enzymes.
