The impact of the phyto-oestrogen genistein on swine granulosa cell function

Soya and soybean products used in swine feeding contain genistein, a non-steroidal phytoestrogen which has been demonstrated to influence endocrine functions. This observation lead us to design this study in order to evaluate the effect of genistein on swine granulosa cell steroidogenesis and proliferation. In the attempt to unravel the genistein signal transduction mechanisms, we verified the effect of lavendustin, a Tyrosine Kinase (TK) inhibitor, and the potential involvement of NO/cGMP pathway. Finally, since angiogenesis is essential for follicle development, we tested the effect of the phytoestrogen on VEGF production and on granulosa cell redox status, because free radical species modulate neovascularization. Our data provide evidence that genistein interferes with granulosa cell steroidogenesis while it does not modulate cell growth: this effect could be at least partially produced by inhibiting TK – dependent signalling systems. On the contrary, NO/cGMP pathway or VEGF production can be excluded as signalling mechanism involved in phytoestrogen effects. Remarkably, genistein stimulates hydrogen peroxide production thus potentially inhibiting follicular angiogenesis. Collectively, these results suggest that genistein consumption could potentially negatively impact swine reproductive function.