Involvement of peroxisome proliferator-activated receptors in the estradiol production of ovine Sertoli cells

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors of transcription factors composed of three family members: PPARα, PPARβ/δ and PPARγ. This study was aimed to evaluate the role of PPARs in the estradiol production via follicle stimulating hormone (FSH) in the ovine Sertoli cells. At the first step, transcripts of PPARα, PPARβ /δ and PPARγ were evaluated by quantitative real time PCR (qRT-PCR) in the ovine Sertoli cells in vitro after FSH treatment. PPARγ transcript was increased in FSH-treated cells while PPARα and PPAR β /δ transcripts were unchanged. At the second step, Pioglitazone as PPARγ agonist and 2-chloro-5-nitrobenzanilide (GW9662) as PPARγ antagonist were used in the FSH-treated Sertoli cells and then, the estradiol production and aromatase transcript were evaluated. Aromatase transcript was increased by pioglitazone in the FSH-treated Sertoli cells while GW9662 did not change its transcript. The estradiol production was increased by low concentrations of pioglitazone in FSH-treated Sertoli cells while the production of this hormone was decreased by the high concentration of Pioglitazone. The GW9662 did not change the production of estradiol in FSH-treated Sertoli cells. It is concluded that FSH regulates the estradiol production and aromatase expression in a way independently of PPARβ/δ and PPARα activation, although FSH increases the transcript of PPARγ and in this way, it could affect (mostly increase) aromatase transcript and estradiol production. Probably, this effect of FSH in the estradiol production via PPARγ is only a servo-assist mechanism which if it was inhibited, the estradiol production was not considerably affected.