Bovine ovarian follicular growth and development correlate with lysophosphatidic acid expression. Sinderewicz E et al. (2017) The basis of successful reproduction is proper ovarian follicular growth and development. In addition to prostaglandins and vascular endothelial growth factor, a number of novel factors are suggested as important regulators of follicular growth and development: PGES, TFG, CD36, RABGAP1, DBI and BTC. This study focuses on examining the expression of these factors in granulosa and thecal cells that originate from different ovarian follicle types and their link with the expression of lysophosphatidic acid (LPA), known local regulator of reproductive functions in the cow. Ovarian follicles were divided into healthy, transitional, and atretic categories. The mRNA expression levels for PGES, TFG, CD36, RABGAP1, DBI and BTC in granulosa and thecal cells in different follicle types were measured by real-time PCR. The correlations among expression of enzymes synthesizing LPA (autotaxin, phospholipase A2), receptors for LPA and examined factors were measured. Immunolocalization of PGES, TFG, CD36, RABGAP1, DBI and BTC was examined by immunohistochemistry. We investigated follicle-type dependent mRNA expression of factors potentially involved in ovarian follicular growth and development, both in granulosa and thecal cells of bovine ovarian follicles. Strong correlations among receptors for LPA, enzymes synthesizing LPA, and the examined factors in healthy and transitional follicles were observed, with its strongest interconnection with TFG, DBI and RABGAP1 in granulosa cells, and TFG in thecal cells; whereas no correlations in atretic follicles were detected. A greater number of correlations were found in thecal cells than in granulosa cells as well as in healthy follicles than in transitional follicles. These data indicate the role of LPA in the growth, development and physiology of the bovine ovarian follicle.//////////////////
Expression regulated by
LH
Comment
Gene expression profiling of bovine preovulatory follicles: Gonadotropin surge and prostanoid dependent up-regulation of genes potentially linked to the ovulatory process. Li Q et al. The molecular mechanisms of ovulation and luteinization have not been well established, partially due to lack of a comprehensive understanding of functionally significant genes up-regulated in response to an ovulatory stimulus and the signaling pathways involved. In the present study, transcripts increased in bovine preovulatory follicles following a GnRH-induced LH surge were identified using microarray technology. Increased expression of 368 and 878 genes was detected at 12 (368 genes) and 20 h (878 genes) following GnRH injection. The temporal, cell specific and prostanoid dependent regulation of selected genes (ADAM10, DBI, CD36, MTSS1, TFG, and RABGAP1) identified from microarray studies and related genes (ADAM17, AREG) of potential significance were also investigated. Expression of mRNA for DBI and CD36 was simultaneously up-regulated in theca and granulosa cells following the LH surge, whereas temporal regulation of ADAM10, MTSS1, TFG and RABGAP1 was distinct in the two cell compartments and increased granulosa TFG and RABGAP1 mRNA was prostanoid dependent. AREG mRNA was increased in theca and granulosa cells at 12 and 24 h following GnRH injection. ADAM17 mRNA was increased in theca, but reduced in granulosa cells 24 h following GnRH injection. The increased ADAM17 and AREG mRNA was prostanoid dependent. ADAM10 and ADAM17 protein were increased specifically in the apex but not the base of preovulatory follicles and the increase in ADAM17 was prostanoid dependent. Results reveal novel information on regulation of preovulatory gene expression and suggest a potential functional role for ADAM10 and ADAM17 proteins in the region of follicle rupture.