Basic FGF Promotes Proliferation of Ovarian Granulosa Cells in the Laying Chickens Via FGFR1 and PKC Pathway

Abstract

The proliferating effect of basic fibroblast growth factor (bFGF) on granulosa cells from ovarian pre-hierarchical follicles was evaluated in the laying chickens. Expression of bFGF receptor 1 (FGFR1) from small yellow follicles was determined by immunohistochemistry and RT-PCR. The FGFR1 protein and mRNA were intensively expressed in the granulosa layer. After 8- to 24-h treatment with bFGF (0.1-100 ng/ml), the proliferation of cultured granulosa cells was remarkably enhanced in a dose- and time-dependent manner. The FGFR1 antagonist SU5402 inhibited bFGF-induced cell proliferation. This stimulating effect was further confirmed by 5-bromo-2-deoxyuridine incorporation and terminal transferase dUTP nick end-labelling assay. Immunocytochemistry of protein kinases A (PKA) and C (PKC) showed that the pro-proliferation action of bFGF predominantly activated PKC expression. Meanwhile, the bFGF-induced cell proliferation was significantly promoted by PKC activator PMA and inhibited by PKC inhibitor H(7) (p < 0.05). In addition, the bFGF-elicited cell proliferation was accompanied with increased mRNA expression of the cell cycle-regulating genes including cyclins D1 and E1, cyclin-dependent kinases 2 and 6. In conclusion, bFGF promoted the proliferation of ovarian granulosa cells through binding with FGFR1 and involving PKC pathway in the pre-hierarchical follicles of the laying chickens.

Fibroblast growth factor 9 (FGF9) regulation of cyclin D1 and cyclin-dependent kinase-4 in ovarian granulosa and theca cells of cattle

“…The only study characterizing CCND1 mRNA in bovine GC reported no change during an estrous cycle, while both CCND2 and CCND3 mRNA expression differed among phases of the estrous cycle (Shimizu et al, 2013). However, CCND1 mRNA is induced by GDF9 in human GC (Huang et al, 2009) and by EGF, FGF2 and ginsenosides in chicken GC (Tan et al, 2010; Lin et al, 2011; 2012). In endometrial tissue, FGF9 induces CCND1 (Schwartz et al, 2003; Wing et al, 2005; Chan et al, 2012).…”

Fibroblast growth factor 2 induces proliferation and distribution of G2/M phase of bovine endometrial cells involving activation of PI3K/AKT and MAPK cell signaling and prevention of effects of ER stress

“…FGF2 signaling induces phosphorylation of tyrosine residues activating protein kinase C (PKC), MAPK, and PI3K pathways through ligand-binding dimerization of FGFR (Dorey & Amaya, 2010). Among the reproductive and embryonic tissues, FGF2 stimulates proliferation of avian granulosa cells of ovary by activation of PKC pathways after binding FGFR1 (Lin, Jia, Zeng, Mi, & Zhang, 2012). In addition, FGF2 activates migration of ovine trophoblast cells through MAPKdependent signal transduction (Yang et al, 2011).…”

Follicle populations and gene expression profiles of Nelore and Angus heifers with low and high ovarian follicle counts

“…Basic FGF ( bFGF ) plays diverse roles in cell proliferation and differentiation during embryo development. Specifically, in ovarian germ cell development, bFGF accelerates cell proliferation by binding with FGFR1 and maintaining its undifferentiated status (He et al, ; Lin, Jia, Zeng, Mi, & Zhang, ). These two genes, along with NTRK1 , which is discussed above, represent three out of the five membrane receptors in the cell proliferation portion of the MAPK pathway.…”