Effects of Daidzein on mRNA Expression of Gonadotropin Receptors and P450 Aromatase in Ovarian Follicles of White Silky Fowls

Effects of daidzein on expression of mRNAs of gonadotropin receptors (FSHR, LHR) and P450 aromatase (P450arom) were evaluated in ovarian follicles of white silky fowls. The hens were 13 months old in the post-peak period of egg laying and were randomly allocated as control and daidzein-treated groups, with daidzein supplemented to the basal diet at 10 mg/kg for 7 consecutive weeks. The mRNA expression of related genes was measured by semi-quantitative RT-PCR in the granulosa layers of the preovulatory follicle (PRF: F1, F2 ...) and follicular layers of the small yellow follicle (SYF), large white follicle (LWF) and atretic follicle (ATF). Results showed that daidzein supplementation significantly increased the number of SYF and LWF (p<0.05). The relative abundance of the FSHR mRNA decreased in the granulosa layers from F3 to F1, but LHR mRNA displayed opposite developmental changes. P450arom mRNA was highest in the SYF, but was very low in the granulosa layers after follicles finished selection. Treatment with daidzein resulted in increased mRNA expression of FSHR in F3 granulosa layer, LHR in granulosa layers of F3 to F1 and P450arom in LWF (p<0.05). These results indicated that dietary supplementation of daidzein up-regulated mRNA expression of gonadotropin receptors and P450arom to improve the development of preovulatory follicles in white silky fowls after the peak-laying period. (