Christopher A Price- PhD
- Professor at Université de Montréal
Christopher A Price
- PhD
- Professor at Université de Montréal
About
160
Publications
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Introduction
co-Editor-in-Chief, Reproduction.
Current institution
Publications
Publications (160)
In brief
Irisin is a muscle and adipose-derived hormone that is secreted in response to negative energy balance in cattle. We show here that irisin reduced follicle growth and theca cell function.
Abstract
At the onset of lactation, dairy cattle are anestrous owing mainly to a state of negative energy balance. Adipose tissue is mobilized to meet t...
In brief
Dairy cattle experience a period of infertility postpartum that is caused in part by the development of IGF1/insulin resistance. This study suggests that an adipokine, FNDC3A, reduces IGF1-dependent glycolysis and may contribute to postpartum infertility.
Abstract
Dairy cows go through a period of subfertility after parturition, triggered...
Suboptimal LH surges can lead to delayed or absent ovulation during reproductive management programs in cattle. Several signaling pathways may enhance the LH signal, potentially including growth factors. In the present study, we determined whether Fibroblast growth factor 18 (FGF18), which mimics some actions of the LH surge on granulosa cells, may...
Suboptimal LH surges can lead to delayed or absent ovulation during reproductive management programs in cattle. Several
signaling pathways may enhance the LH signal, potentially including growth factors. In the present study, we determined whether Fibroblast growth factor 18 (FGF18), which mimics some actions of the LH surge on granulosa cells, may...
Simple Summary
Cystic ovarian disease is an important ovarian disorder that leads to anovulatory infertility in dairy cows. In the present study, we used spontaneous ovarian follicular cysts to show the first evidence that the deregulation of Hippo pathway effector yes-associated protein expression and/or activity can be a potential key to better u...
Cattle are deemed less susceptible to mycotoxins due to the limited internal exposure resulting from rumen microbiota activity. However, the significant amounts of Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEN) frequently detected in bovine follicular fluid samples suggest that they could affect ovarian function. Both mycotoxins tri...
Purpose
To assess the effects of the oocyte on mRNA abundance of FSHR, AMH and major genes of the maturation cascade (AREG, EREG, ADAM17, EGFR, PTGS2, TNFAIP6, PTX3, and HAS2) in bovine cumulus cells.
Methods
(1) Intact cumulus-oocyte complexes, (2) microsurgically oocytectomized cumulus-oolema complexes (OOX), and (3) OOX + denuded oocytes (OOX+D...
Deoxynivalenol (DON) is a major mycotoxin present in animal feed and negatively affects growth and reproduction in farm species, including pigs and cattle. The mechanism of DON action involves the ribotoxic stress response (RSR), and it acts directly on ovarian granulosa cells to increase cell death. In ruminants, DON is metabolized to de-epoxy-DON...
Cumulus cells from cumulus-oocyte complexes (COC) matured in vitro in serum-free medium show high incidence of apoptosis and DNA double-strand breaks (DSB). This study aimed to characterize the transcript expression profile of selected genes involved in DNA repair mechanisms in bovine cumulus cells cultured with bovine serum albumin (BSA) or fetal...
Vitamin D (VD) is one of the important nutrients required by livestock; however, VD deficiency is reported to be widespread. Earlier studies have suggested a potential role for VD in reproduction. Studies on the correlation between VD and sow reproduction are limited. The aim of the current study was aimed to determine the role of 1,25-dihydroxy vi...
In brief
Fertility in the dairy cow is low during the post-partum period of negative energy balance and high plasma irisin concentrations. This study shows irisin modulates granulosa cell glucose metabolism and impairs steroidogenesis.
Abstract
Fibronectin type III domain-containing 5 (FNDC5) is a transmembrane protein discovered in 2012 that is c...
This study examined whether publication outcome was affected by the gender of author, handling associate editor (AE), or reviewer, and whether there was gender bias in reviewer selection, in the journal Reproduction. Analyses were carried out on 4289 original research manuscripts submitted to the journal between 2007 and 2019. Both female and male...
Ovulatory disorders are a major cause of infertility in humans as well as economically important species. In physiological conditions, the LH surge induces the expression of epidermal growth factor (EGF)-like ligands that activate the EGR receptor (EGFR) and subsequently the mitogen-activated protein kinase (MAPK) pathway. The magnitude and duratio...
The peripartum period in dairy cows is frequently associated with excessive lipolysis due to Negative Energy Balance (NEB). These metabolic disorders are the cause of various pathologies. Some metabolites such as β-hydroxybutyrate (BHBA) and Non-Esterified Fatty Acids (NEFA) are known to be biomarkers of NEB in dairy cows. The involvement of adipok...
Dietary stress such as obesity and short-term changes in energy balance can disrupt ovarian function leading to infertility. Adipose tissue secretes hormones (adipokines), such as leptin and adiponectin, that are known to alter ovarian function. Muscles can also secrete endocrine factors, and one such family of myokines, the eleven Fibronectin type...
It is well known that about 99% of ovarian follicles in mammals suffer from a degenerative process known as atresia, which is a huge waste of genetic resource in female animals. Studies have shown that activin A (ACT‐A) is located in ovarian granulosa cells and has different effects in granulosa cell depending on species. Although granulosa cells p...
Increasing the efficiency of farm animal reproduction is necessary to reduce the environmental impact of food production systems. One approach is to increase the number of healthy eggs (oocytes) produced per female for fertilization, thus it is important to understand factors that decrease oocyte health. One paracrine factor that decreases ovarian...
Failure to ovulate is a major cause of infertility. The critical pathway that induces ovulation involves the EGF and MAPK phosphorylation, but studies in rodents have suggested that the Hippo activator, YAP, is also involved. It is unknown whether YAP-dependent transcriptional activity is important for the LH- or EGF-induced ovulatory cascade in mo...
Controling the duration and amplitude of mitogen activated protein kinase (MAPK) signaling is an important element in deciding cell fate. One group of intracellular negative regulators of MAPK activity is a subfamily of the dual specificity phosphatase (DUSP) superfamily, of which up to 16 members have been described in ovarian granulosa cells. Gro...
This review resulted from an international workshop and presents a consensus view of critical advances over the past decade in our understanding of follicle function in ruminants. The major concepts covered include: (1) the value of major genes; (2) the dynamics of fetal ovarian development and its sensitivity to nutritional and environmental influ...
Growth factors regulate ovarian follicle development and they signal through intracellular pathways including mitogen-activated protein kinase (MAPK) phosphorylation, which is negatively regulated by a subfamily of 23 dual-specificity phosphatases (DUSP). Using sheep granulosa cells as a model, we detected mRNA encoding 16 DUSPs in vivo and in vitr...
Ovarian fibrosis is associated with increased expression of the transcription factor, Early growth response-1 (EGR1) and connective tissue growth factor (CCN2) in granulosa cells. The transcriptional activity of EGR1 is under negative feedback control by NAB1 and NAB2, but little is known about NAB expression in granulosa cells. Using a well-define...
Contamination of animal feed with Fusarium spp results in accumulation of mycotoxins including deoxynivalenol. In animals, deoxynivalenol is metabolized to de-epoxy deoxynivalenol (DOM-1), which is generally considered to be a non-toxic metabolite; however, recent studies demonstrated that DOM-1 can reduce steroid production and induce apoptosis in...
The Canadian dairy industry has been using in vivo and in vitro assisted reproductive technologies to produce embryos. Technological improvements have helped increase the number and quality of embryos produced, but genetic and genomic tools for improving these traits have yet to be assessed for the Canadian Holstein population. Genetic parameters a...
Follicle growth and granulosa cell health are dependent on the secretion of estradiol from granulosa cells. Estradiol is synthesized from androgen precursor by cytochrome P450 aromatase (CYP19A1), and in cattle CYP19A1 messenger RNA has a short half‐life but a long (3.5 kb) 3′‐untranslated region (3′UTR), suggesting that posttranscriptional regulat...
Simple Summary
Arachidonic acid (AA) is one of the polyunsaturated fatty acids that presents in a very high proportion in the mammalian follicular fluid. However, the mechanism of its effects on bovine ovarian granulosa cells is not clear. In the present study, we found that arachidonic acid plays an important role in regulating cell proliferation,...
Purpose
We first assessed regulation of FGF2 expression in cumulus cells by FSH and oocyte-secreted factors during in vitro maturation (IVM). Then, we tested the hypothesis that FGF2 regulates meiotic progression, cumulus expansion, and apoptosis in cumulus-oocyte complexes (COC) undergoing IVM.
Methods
In vitro maturation of bovine COC was utiliz...
The generation of free-radicals such as nitric oxide has been implicated in the regulation of ovarian function,
including ovulation. Tissues that generate nitric oxide typically generate another free-radical gas, hydrogen sulfide
(H2S), although little is known about the role of H2S in ovarian function. The hypothesis of this study was
that H2S...
In cattle and other species, the fetal ovary is steroidogenically active before follicular development commences, and there is evidence that estradiol and progesterone inhibit follicle formation and activation. Estradiol levels decline sharply around the time of follicle formation. In the present study, we hypothesized that FGF10 and FGF18, which i...
The aim of this study was to determine the expression of fibroblast growth factor 22 (FGF22) in the bovine corpus luteum (CL) and to investigate the effects of in vivo total or partial cloprostenol-induced luteolysis on the mRNA abundance of FGF22 and its receptor, FGFR1B. Corpora lutea at different stages of development were then dissected from ab...
Much work has been conducted over the years to determine the major factors that control follicle growth, including the role of FSH, LH and IGF1. These factors permit the dominant follicle to grow while subordinate follicles regress. The dominant follicle enters a phase of growth, and then that growth slows as the follicle reaches maximum size. The...
The theca cell layer of the ovarian follicle secretes growth factors that impact the function of granulosa cells. One such factor is fibroblast growth factor 18 (FGF18) that causes apoptosis of granulosa cells, however it is not known if FGF18 induces apoptosis also in theca cells. Addition of recombinant FGF18 to bovine theca cells in vitro inhibi...
Superovulation or ovum pick-up and in vitro fertilization are technologies used to produce an increased number of embryos from elite females. Embryo production traits have been shown to be heritable, but the genes that cause this variability have not yet been assessed. The main objectives of this study were to perform a genome-wide association stud...
Tribbles homolog (TRIB) 1, 2 and 3 represent atypical members of the serine/threonine kinase superfamily and are homologs of Drosophila tribbles. TRIB2 mRNA is rapidly induced by mitogens, has a short half‐life, and is expressed in a cell‐specific manner. We previously identified TRIB2 as a differentially expressed gene in granulosa cells (GC) of b...
Several growth factor families have been shown to be involved in the function of the female reproductive tract. One subfamily of the fibroblast growth factor (FGF) superfamily, namely the FGF8 subfamily (including FGF17 and FGF18), has become important as Fgf8 has been described as an oocyte-derived factor essential for glycolysis in mouse cumulus...
The mycotoxin deoxynivalenol (DON) has been shown to inhibit ovarian granulosa cell function in cattle in vitro, but it is not known whether DON or its metabolite deepoxy-DON (DOM-1) affect theca cell function. The objectives of the present study were to determine the effects of DON and of DOM-1 on theca cell steroidogenesis and apoptosis, and to d...
Fibroblast growth factors (FGF) modify cell proliferation and differentiation through receptor tyrosine kinases, which stimulate the expression of transcription factors including members of the early growth response (EGR) family. In ovarian granulosa cells, most FGFs activate typical response genes, although the role of EGR proteins has not been de...
The number of embryos produced by Holstein donors has been shown to be heritable, so it could be possible to genetically select for this trait to improve the efficiency of the assisted reproductive technology (ART) in dairy cattle. Another important parameter to consider for achieving good results from ART is embryo quality because embryos of good...
In vivo, oocyte maturation is triggered by the ovulatory LH surge, whereas in vitro it is precociously induced when the cumulus–oocyte complex is removed from the follicle. Natriuretic peptide C (NPPC) delays germinal vesicle breakdown (GVBD) while increasing oocyte–cumulus communication during in vitro maturation (IVM) in cattle. In the present st...
In vitro maturation (IVM) of oocytes in cattle is inefficient, and there is great interest in the development of approaches to improve maturation and fertilization rates. Intraovarian signaling molecules are being explored as potential additives to IVM media. One such factor is kit ligand (KITL), which stimulates the growth of oocytes. We determine...
Multiple embryos can be produced from a heifer or cow donors using an in vivo or an in vitro technique. Comparisons of the number of embryos produced by the same donors as heifers and cows and using different techniques are limited. The main objectives of this study were to assess the genetic correlation between the number of embryos produced by Ho...
Superovulation of dairy cattle is frequently used in Canada. The cost of this protocol is high, and so is the variability of the outcome. Knowing the superovulatory potential of a donor cow could influence the breeder's decision to superovulate it or not. The main objective of this study was to perform a genetic analysis for superovulatory response...
Whereas the roles of the canonical wingless-type MMTV (mouse mammary tumor virus) integration site family (WNT) signaling pathway in the regulation of ovarian follicle growth and steroidogenesis are now established, noncanonical WNT signaling in the ovary has been largely overlooked. Noncanonical WNTs, including WNT5a and WNT11, are expressed in gr...
Fibroblast growth factors have been shown to alter growth and differentiation of reproductive tissues in a variety of species. Within the female reproductive tract, the effects of FGFs have been focused on the ovary, and the most well-studied is FGF2, which stimulates granulosa cell proliferation and decreases differentiation (decreased steroidogen...
There is evidence that regulation of follicle selection in cattle involves locally produced growth factors. In the present study, we investigated the expression of members of the fibroblast growth factor (FGF) 7 family during follicle deviation. The largest and second largest follicles were recovered during the second day of a synchronised follicle...
Alopecia X in dogs is a noninflammatory alopecia that may be caused by a hormonal dysfunction. It may be similar to androgenic alopecia in men that is caused by the effect of dihydrotestosterone (DHT). The 5α-reductase isoenzymes, 5αR1 and 5αR2, and a recently described 5αR3, are responsible for the conversion of testosterone into DHT. However, whi...
Mycotoxins can reduce fertility and development in livestock, notably in pigs and poultry, although the effect of most mycotoxins on reproductive function in cattle has not been established. One major mycotoxin, deoxynivalenol (DON), targets immune cells and activates the ribotoxic stress response involving MAPK activation, but also inhibits oocyte...
Although the various members of the fibroblast growth factor (FGF) family are generally mitotic, one member, FGF18, has been shown increase the rate of apoptotsis of ovarian granulosa cells. In the present study, we determined first whether granulosa cells express FGF18 and we then explored the mechanism through which FGF18 increases apoptosis in v...
Sef is a tumor suppressor and an inhibitor of growth factors as well as of pro-inflammatory cytokine signaling. In the present study we examined the regulation of Sef expression by gonadotropins during ovarian folliculogenesis. In sexually immature mice, in situ hybridization (ISH) localized Sef gene expression to early developing oocytes and granu...
In rabbits and rodents, nitric oxide (NO) is generally considered to be critical for ovulation. In monovulatory species, however, the importance of NO has not been determined, nor is it clear where in the preovulatory cascade NO may act. The objectives of the present study were (1) to determine if nitric oxide synthase (NOS) enzymes are regulated b...
The ovarian promoter of the primate and rodent genes encoding cytochrome P450 aromatase (CYP19A1) are robustly responsive to forskolin in luteinized cell models, whereas the ruminant ovarian promoter is minimally active. We explored this discrepancy by investigating the activity of the bovine ovarian promoter in two bovine granulosa cell models, lu...
Fibroblast growth factors (FGFs) are involved in the paracrine modulation of ovarian function, and typically exert mitogenic effects
by inhibiting apoptosis and increasing cell proliferation. However, in a previous study with bovine granulosa cells we observed one FGF had
the opposite effect; addition of FGF18 increased caspase-3 activation and inc...
Very little is known about the effects of hormonal synchronization of follicle waves and superovulation on the estrogen content of a cow's milk. The objective of this study was to determine the effect in dairy cows of synchronization with estradiol-17β (E2) and progesterone (P4) on milk E2 concentrations and to compare these levels with those achie...
Oocyte secreted factors (OSF) regulate differentiation of cumulus cells and are of pivotal relevance for fertility. Bone morphogenetic protein 15 (BMP15) and fibroblast growth factor 10 (FGF10) are OSFs and enhance oocyte competence by unknown mechanisms. We tested the hypothesis that BMP15 and FGF10, alone or combined in the maturation medium, enh...
FSH induces expansion of bovine cumulus–oocyte complexes (COCs) in cattle, which can be enhanced by oocyte-secreted factors (OSFs). In this study it was hypothesised that FSH stimulates COC expansion in part from direct stimulation of the epidermal growth factor (EGF)-like ligands amphiregulin (AREG), epiregulin (EREG) and betacellulin (BTC), but a...
Several fibroblast growth factors (FGFs) alter ovarian granulosa cell function, including FGF1, FGF4 and FGF10. These ligands exhibit different patterns of receptor activation, and their mechanisms of action on granulosa cells remain unknown. The objective of the present study was to identify the major pathways and target genes activated by FGF1, F...
Low fertility in the dairy industry is a multifaceted problem, but poor follicle growth and failure to ovulate are major contributors. The health of the granulosa cell layer of the follicle is key to follicle growth, and an essential mitogenic, anti-apoptotic product of granulosa cells is estradiol. The rate-limiting enzyme for estradiol synthesis...
The oocyte and cumulus cells (CC) secrete paracrine factors that regulate COC differentiation. Oocyte derived BMP15 and FGF10 bind to receptors in CC, which in turn secrete KL that signals to the oocyte. KL was shown to enhance nuclear maturation in rodents. The aim of this study was to determine the effects of KL on oocyte maturation in cattle and...
Fertility in dairy and beef cows is negatively affected by stressors such as lamness and high milk yield, and one site of action of these stressors is the process of ovulation. Rupture of the follicle is initiated by the preovulatory surge of LH, which stimulates granulosa cell release of the EGF-like ligands epiregulin (EREG) and amphiregulin (ARE...
In dairy cows, there is evidence that failure to respond to superovulation protocols is a heritable trait. In women, genotyping for the p.N680S single nucleotide polymorphism (SNP) in the follicle-stimulating hormone receptor (FSHR) gene may help identify poor responders before ovarian stimulation is initiated. Our objectives were to identify SNPs...
The objective was to establish a cell line-based bioassay for FSH in horse serum for screening samples with high eCG bioactivity. A cell line (HEK293) was transiently cotransfected with an FSH reporter expression plasmid and a cAMP-responsive β-galactosidase reporter plasmid. Cells were bulk frozen, and thawed for assay purposes. This assay was spe...
Fibroblast growth factors (FGFs) are involved in paracrine control of follicle development. It was previously demonstrated that FGF10 decreases estradiol (E(2)) secretion in granulosa cell culture and that theca cell FGF10 mRNA expression is decreased in healthy follicles from abattoir ovaries. The main objectives of this study were to evaluate FGF...
It is generally understood that angiotensin II (AngII) promotes follicle atresia in rats, although recent data suggested that this may not be true in cattle. In this study, we aimed to determine in vivo whether AngII alters follicle development in cattle, using intrafollicular injection of AngII or antagonist into the growing dominant follicle or t...
Angiotensin II (AGT-2) induces follicular prostaglandin release in a number of species and ovulation in rabbits. Conversely, AGT-2 antagonists block ovulation in cattle. To determine the mechanism of action of AGT-2, we used a bovine granulosa cell model in which luteinizing hormone (LH) increased the expression of genes essential for ovulation in...
The oocyte actively participates in the regulatory mechanisms of cumulus-oocyte complex (COC) maturation via secretion of paracrine factors. BMP15 and FGF10 were localized to the oocyte and improved blastocyst rates following IVM/IVF in cattle. In this study we tested the hypotheses that FGF10 and BMP15 would enhance cumulus expansion and that the...
Fibroblast growth factors (FGFs) alter ovarian function, at least in part by inhibiting steroid hormone secretion and affecting survival of granulosa cells. The mechanism of action of FGFs in ovarian follicle cells is largely unknown; in the present study we identified the major pathways used by FGF2 in non-luteinizing granulosa cells cultured unde...
Nitric oxide (NO) is a potential regulator of ovarian follicle growth, and ovarian granulosa cells reportedly generate NO in response to gonadotrophins, suggesting that the regulated form of nitric oxide synthase (iNOS) is present. The objectives of the present study were to gain insight into the expression and role of iNOS in the follicle. Messeng...
Some mammalian carnivores compensate for prey shortage during the summer by increasing their consumption of wild berries. We tested whether such prey shortage affected all body components (e.g., fat, protein, water) equally, and whether it could affect reproduction. Two groups of wild red foxes (Vulpes vulpes) were kept in captivity: the first grou...
Considerable attention is currently paid to oocyte-derived secreted factors that act upon cumulus and granulosa cells. Also important for follicle development are somatic cell-derived secreted factors. This is illustrated by the ability of granulosa cell-derived Kit ligand (KITL) to promote primordial follicle activation, and the loss of follicle d...
Fibroblast growth factors (FGF) are involved in paracrine signaling between cell types in the ovarian follicle. FGF8, for example, is secreted by oocytes and controls cumulus cell metabolism. The closely related FGF18 is also expressed in oocytes in mice. The objective of this study was to assess the potential role of FGF18 in follicle growth in a...
Fibroblast growth factor 17 (FGF17) is a member of the FGF8 subfamily that appears to be relevant to folliculogenesis and oogenesis, as the prototype member FGF8 is an oocyte-derived protein that signals to cumulus cells. FGF8 has structural and receptor-binding similarities to FGF17, whose expression in the ovary has not been reported. In this stu...
Angiotensin II (AngII) has been shown to be involved in the regulatory mechanism of ovulation and oocyte nuclear and cytoplasmic maturation in cattle. In rats, AngII induces apoptosis in granulosa cells and atresia of antral follicles during follicular development. However, the angiotensin converting enzyme (ACE) mRNA expression increases at the en...
Understanding the paracrine events that regulate fertility in the cow is necessary not only because of the agricultural importance of this species, but also its potential use as a model for humans. Fibroblast growth factors (FGF) and their receptors are involved in the paracrine modulation of ovarian function. For example, FGF2, 7 and 10 inhibit es...
In the mammalian ovary, fibroblast growth factors (FGF) 8 and 10 are expressed in oocytes, and are candidates for paracrine signalling to the developing follicular cells. Moreover, there is evidence that FGFs and bone morphogenetic protein 15 (BMP15) are essential regulators of cellular functions and may contribute to oocyte development and compete...
Fibroblast growth factors (FGF) are grouped into several FGF families according to structural and functional properties, and play a number of different physiological roles including regulation of folliculogenesis. Two of the three members of the FGF7 family (FGF7, 10 and 22) were previously assessed in the follicle; FGF7 and 10 were principally loc...
Matrix metalloproteinases (MMP) are key enzymes involved in tissue remodeling. Within the ovary, they are believed to play a major role in ovulation, and have been linked to follicle atresia. To gain insight into the regulation of MMPs, we measured the effect of hormones and growth factors on MMP2 and MMP9 mRNA levels in non-luteinizing granulosa c...
To determine if initial cell plating density alters steroidogenesis and the E(2):P ratio in granulosa cells in long-term serum-free culture.
Experimental study.
Academic institution.
Cattle of slaughterhouse origin.
Culture of granulosa cells in vitro at different cell plating density.
Steroid secretion was measured by RIA, mRNA levels were measure...
Survival and inhibitory factors regulate steroidogenesis and determine the fate of developing follicles. The objective of this study was to determine the role of transforming growth factor-beta1 (TGFB1) in the regulation of estradiol-17beta (E(2)) and progesterone (P(4)) secretion in FSH-stimulated bovine granulosa cells. Granulosa cells were obtai...
There is evidence that fibroblast growth factors (FGFs) are involved in the regulation of growth and regression of the corpus luteum (CL). However, the expression pattern of most FGF receptors (FGFRs) during CL lifespan is still unknown. The objective of the present study was to determine the pattern of expression of ‘B’ and ‘C’ splice variants of...
Angiotensin II (AngII) is best known for its role in blood pressure regulation, but it also has documented actions in the reproductive system. There are two AngII receptors, type 1 (AGTR1) and type 2 (AGTR2). AGTR2 mediates the noncardiovascular effects of AngII and is expressed in the granulosa cell layer in rodents and is associated with follicle...
Angiotensin II (ANGII) induces follicular prostaglandin release in a number of species, and is involved in ovulation in cattle and rabbits. ANGII signals through either the type 1 (AT1) or type 2 (AT2) receptor, and its non-cardiovascular effects are believed to be mediated through AT2. Ovulation is associated with the expression of key genes in gr...
Developmental competence of the oocyte is acquired during folliculogenesis when the oocyte actively transcribes and stores mRNA for use during maturation. Differences in the relative abundance of mRNA between in vivo and in vitro matured bovine oocytes has been described for some developmentally important genes. It is also known that in vitro cultu...
Fibroblast growth factors (FGF) have been recognised as important local regulators of follicle development. FGF-17 and FGF-18 belong to the FGF-8 subfamily and exhibit similar amino acid sequences and receptor affinity. They induce cell proliferation and differentiation through activation of FGFR-3c and FGFR-4, recently detected (mRNA) in granulosa...
Angiotensin II (AngII) is involved in the control of some reproductive events in females. In cattle, AngII has a pivotal effect in ovulation and prevents the inhibitory effect of follicular cells on bovine oocyte nuclear maturation. The role of AngII in follicular growth has been studied only in rats, and it induces apoptosis in granulosa cells and...
There is evidence that several fibroblast growth factors (FGFs) are involved in growth and development of the corpus luteum (CL), but many FGFs have not been investigated in this tissue, including FGF10. The objective of this study was to determine if FGF10 and its receptor (FGFR2B) are expressed in the CL. Bovine CL were collected from an abattoir...
The prevalence of obesity is increasing in dogs as well as in humans. C-reactive protein (CRP) is an important tool for the detection of inflammation and/or early tissue damage and is linked to obesity in humans. The objective of the present study was to determine if serum CRP levels are altered in obese dogs. Fifteen lean (control group) and 16 ov...
The Serpins comprise a family of proteins that bind irreversibly to and inactivate serine proteases such as thrombin and plasminogen activators. This review summarizes the current knowledge of one Serpin, SerpinE2 (also known as protease nexin-1, PN-1) in the reproductive system. By virtue of the ability to regulate the activity of secreted proteas...
Some fibroblast growth factors (FGFs) affect ovarian follicle cell growth and/or differentiation. Whereas many FGFs activate several FGF receptors, FGF7 and FGF10 primarily activate only one, FGFR2B. As FGF7 is produced by bovine theca cells and acts on granulosa cells, we tested the hypothesis that FGF10 may also play a role in folliculogenesis in...
The aim of this study was to validate an enzyme-linked immunosorbent assay (ELISA) for the measurement of progesterone (P4) in mares. Specifically, the objectives were as follows: (1) to determine the specificity and sensitivity of the ELISA test for determination of P4, (2) to measure the potential agreement between the 2 people performing the tes...
Angiotensin II (AngII) is best known for its role in blood pressure regulation, but it also has some documented actions in the reproductive system. There are two AngII receptors, AT1 and AT2. The AT1 receptor mediates a number of well-known AngII effects on smooth muscle contraction, aldosterone secretion and blood pressure regulation, while the AT...
Questions
Question (1)
I'm looking for a serum-free long-term (> 4 d) culture system for mouse granulosa cells. Protocols exist for sheep and cattle, but I cannot find one for mouse. Local colleagues simply say that it doesn't work in mice. Does anyone have any experience with this? What conditions have been attempted (I'd prefer not to repeat all the failed experiments a lot of people may have buried in their lab books!)?
Thanks!
