Influence of caprine arthritis encephalitis on expression of ovulation related genes and activation of primordial follicles cultured in presence of phytohemagglutinin, epidermal growth factor or both

Abstract

This study investigated the levels of mRNA for BMP15, GDF9 and BMPR1B in preantral follicles, as well as in cumulus oocyte complex (COC) and follicular walls from antral follicles of healthy and CAEV infected goats by real-time PCR. In addition, the influence of phytohemagglutinin (PHA) and EGF on activation of primordial follicles and on expression of mRNA for TNFa and its receptors in cultured ovarian tissue from healthy and infected goats was evaluated. The expression of BMP15 and GDF9 in primordial/primary follicles from infected goats was significantly higher than in healthy animals, whereas the expression of BMP15 and GDF9 in secondary follicles from infected goats was significantly lower. The expression of mRNA for BMP15 in follicular wall of antral follicles from infected goats was significantly higher than in healthy goats. CAEV infection did not influence the ability of primordial follicles to develop in vitro, but the presence of EGF in culture medium significantly increased follicular diameter in healthy and infected animals. Ovarian tissue from infected goats cultured in medium with PHA had primordial follicles with larger diameters than those from healthy animals. An increase of mRNAs for TNFα was observed after culturing tissue in presence of both EGF and PHA in healthy animals, but this same treatment promoted a reduction of mRNAs for TNFa and increase of TNFR2 transcripts in infected animals. In conclusion, CAEV influences the expression of mRNA for BMP15 and GDF9 in goat ovarian follicles and PHA and EGF differentially regulate the expression of TNFa and TNFR2 in cultured ovarian tissue.