Evidence for a functional bone morphogenetic protein (BMP) system in the porcine ovary

The present study examined the effects of feeding gilts a high fibre diet from the third post-pubertal oestrus until either day 19 of the same cycle or insemination at the following oestrus on oocyte maturity, embryo survival and associated changes in reproductive hormone concentrations. Gilts fed with the high fibre diet had lower circulating oestradiol concentrations on days 17, 18 and 19 of the cycle and increased LH pulse frequency on day 18. More oocytes recovered on day 19 from gilts receiving the high fibre diet were at metaphase II after 46-h culture in medium containing 10% of their own follicular fluid, despite fewer large (O7 mm) follicles in these gilts when compared with control animals. There was no effect of diet on ovulation rate, corpora lutea size or progesterone concentrations on days 10-12 after insemination, but embryo survival on days 27-29 after insemination was higher in gilts that received the high fibre diet. This study demonstrates that a high fibre diet that increases embryo survival also improves oocyte maturity and provides information on endocrine correlates that may shed light on underlying mechanisms.

Section: Discussionmentioning

confidence: 76%

Beneficial effects of a high fibre diet on oocyte maturity and embryo survival in gilts

Ferguson¹,

Slevin²,

Hunter³

et al. 2007

“…This contrast with the cow where GDF9 mRNA could not be detected in the TC from small or large follicles (Spicer et al 2008). Brankin et al (2005) reported a strong signal for BMP2 and BMP6 proteins in the oocyte of healthy 2-6 mm follicles from mature gilts, and BMP2 was also detected in the GC and TC from the same follicles. Interestingly, these authors also reported BMP6 expression in GC but not in TC.…”

Section: Expression Of Bmps and Bmpr In Pig Folliclesmentioning

confidence: 75%

Temporal regulation of BMP2, BMP6, BMP15, GDF9, BMPR1A, BMPR1B, BMPR2 and TGFBR1 mRNA expression in the oocyte, granulosa and theca cells of developing preovulatory follicles in the pig

Paradis

Novak²,

Murdoch³

et al. 2009

This study aimed to describe the abundance and localization of BMP2, BMP6, BMP15, GDF9, BMPR1A, BMPR1B, BMPR2 and TGFBR1 mRNA during pig preovulatory follicular development and to evaluate their implication in improving follicular maturity in the preovulatory period preceding the second versus first post-weaning oestrus. Oocytes, granulosa (GC) and theca cells (TC) were recovered from antral follicles of primiparous sows at day 1, 2 and 4 after weaning and at day 14, 16 and 20 of their subsequent oestrous cycle. Realtime PCR analysis revealed that with the exception of BMP6 mRNA, which was absent in GC, all genes were expressed in every cell type. Although BMP6, BMP15 and GDF9 mRNA were most abundant in the oocyte, their expression remained relatively constant during follicular development. By contrast, receptor BMPR1B and TGFBR1 expressions in the GC and TC were temporally regulated. BMPR1B mRNA abundance was positively correlated with plasma oestradiol (E 2 ) suggesting that its regulation by oestrogen may be implicated in normal folliculogenesis. Interestingly, the increase in BMPR1B mRNA and protein abundance during the periovulatory period in GC and TC suggests a role for bone morphogenetic protein (BMP) 15 in the ovulatory process. Finally, expression of these ligands and receptors was not associated with potential differences in follicle maturity observed during the second versus first post-weaning preovulatory follicular wave. In conclusion, our results clearly demonstrate the presence of a complex signalling system within the pig follicle involving the transforming growth factor-b superfamily and their receptors, and provide evidence to support a role for BMP15 and BMPR1B during ovulation.

“…Both the precursor and the mature protein of BMP4 contain two potential N-linked glycosylation sites (Cui et al 2001). The precursor forms of BMP2 and BMP6 have been detected in porcine follicular fluid (Brankin et al 2005). Similarly, the precursors of GDF9 and BMP15 and mature GDF9 have been detected in monkey follicular fluid (Duffy 2003).…”

Section: Bmp4 and Female Reproductive Systemmentioning

confidence: 99%

Dynamic expression of bone morphogenetic protein 4 in reproductive organs of female mice

Tanwar¹,

McFarlane²

2011

Various members of the bone morphogenetic protein (BMP) family have been shown to regulate mammalian follicular development by affecting granulosa cell proliferation and steroidogenesis. In situ hybridization studies have shown expression of BMPR1A, BMPR1B, and BMPR2 in the granulosa cells and oocyte of most of the follicles in the ovary, suggesting that these cells have the capacity to respond to BMP signaling. Although much is known about BMP4 signaling, its expression pattern in the female reproductive tract (FRT) is still unclear.The objective of the current study was to characterize the expression of BMP4 and its downstream target proteins (pSMAD1/5/8) in the FRT. In the ovary, BMP4 protein was detected in all the stages of follicular development. Staining for pSMAD1/5/8 was observed in granulosa cells and oocytes of all the stages of follicular development including primordial follicles, suggesting that these follicles are responsive to autocrine/paracrine BMP signaling. In the uterus, BMP4 and pSMAD1/5/8 staining was observed in all three compartments and strongest expression was observed during the estrus phase. BMP4-and pSMAD1/5/8-specific staining was also observed in oviductal epithelium. Different forms (apparent MW: 50, 35, and 15 kDa) of BMP4 were detected in mouse ovary by western blot analysis. In conclusion, these results have defined BMP4 and pSMAD1/5/8 protein expression in the mouse FRTand highlighted the importance of BMP4 in folliculogenesis.