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1.
Domest Anim Endocrinol ; 80: 106712, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35276581

RESUMO

The various fibroblast growth factors (FGF) regulate their function via binding to 4 main FGF receptor (FGFR) subtypes and their splice variants, FGFR1b, FGF1c, FGFR2b, FGFR2c and FGFR3c and FGFR4, but which of these FGFR are expressed in the granulosa (GC) and theca cells (TC), the 2 main cell layers of ovarian follicles, or change during follicular development is unknown. We hypothesized that FGFR1c, FGFR2c and FGFR3c (but not FGFR4) gene expression in GC (but not TC) would change with follicular development. Hence, the objective of this study was to determine if abundance of FGFR1c, FGFR2c, FGFR3c, and FGFR4 mRNA change according to follicular size, steroidogenic status, and days post-ovulation during growth of first-wave dominant follicles in Holstein cattle exhibiting regular estrous cycles. Estrous cycles of non-lactating dairy cattle were synchronized, and ovaries were collected on either d 3 to 4 (n = 8) or d 5 to 6 (n = 8) post-ovulation for GC and TC RNA extraction from small (1-5 mm), medium (5.1 to 8 mm) or large (8.1-18 mm) follicles for real-time PCR analysis. In GC, FGFR1c and FGFR2c mRNA relative abundance was greater in estrogen (E2)-inactive (ie, concentrations of E2 < progesterone, P4) follicles of all sizes than in GC from large E2-active follicles (ie, E2 > P4), whereas FGFR3c and FGFR4 mRNA abundance did not significantly differ among follicle types or days post-estrus. In TC, medium E2-inactive follicles had greater FGFR1c and FGFR4 mRNA abundance than large E2-active and E2-inactive follicles on d 5 to 6 post-ovulation whereas FGFR2c and FGFR3c mRNA abundance did not significantly differ among follicle types or day post-estrus. In vitro experiments revealed that androstenedione increased abundance of FGFR1c, FGFR2c and FGFR4 mRNA in GC whereas estradiol decreased FGFR2c mRNA abundance. Neither androstenedione nor estradiol affected abundance of the various FGFR mRNAs in cultured TC. Taken together, the findings that FGFR1c and FGFR2c mRNA abundance was less in GC of E2-active follicles and FGFR1c and FGFR4 mRNA was greater in TC of medium inactive follicles at late than at early growing phase of the first dominant follicle support an anti-differentiation role for FGF and their FGFR as well as support the idea that steroid-induced changes in FGF and their receptors may regulate selection of dominant follicles in cattle.


Assuntos
Androstenodiona , Células Tecais , Androstenodiona/análise , Androstenodiona/metabolismo , Animais , Bovinos , Estradiol/metabolismo , Feminino , Células da Granulosa/metabolismo , Ovário/metabolismo , RNA Mensageiro/análise , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Células Tecais/metabolismo
2.
Domest Anim Endocrinol ; 63: 48-58, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29413902

RESUMO

We reported previously that fibroblast growth factor 9 (FGF9) acts as an antidifferentiation factor, stimulating proliferation of granulosa cells (GCs) and theca cells (TCs) while suppressing hormone-induced steroidogenesis of these cells. How FGF9 acts to simultaneously suppress steroidogenesis and stimulate proliferation remains to be fully elucidated. Thus, this study was undertaken to clarify the effects of FGF9 on the TC transcriptome. Ovaries were obtained from beef heifers at a local abattoir, TCs were isolated from large antral follicles, and cultured with or without 30 ng/mL of FGF9 for 24 h in the presence of LH and IGF-1. After treatment, total RNA was extracted from TC and processed for microarray using Affymetrix GeneChip Bovine Genome Arrays (n = 4/group). Transcriptome analysis comparing FGF9-treated TC with control TC using 1.3-fold cutoff, and a P < 0.05 significance level identified 355 differentially expressed transcripts, with 164 elements upregulated and 191 elements downregulated by FGF9. The ingenuity pathway analysis (IPA) was used to investigate how FGF9 treatment affects molecular pathways, biological functions, and the connection between molecules in bovine TC. The IPA software identified 346 pathways in response to FGF9 in TC involved in several biological functions and unveiled interesting relationships among genes related to cell proliferation (eg, CCND1, FZD5, and MYB), antioxidation/cytoprotection (eg, HMOX1 and NQO1), and steroidogenesis (eg, CYP11A1 and STAR). Overall, genes, pathways, and networks identified in this study painted a picture of how FGF9 may regulate folliculogenesis, providing novel candidate genes for further investigation of FGF9 functions in ovarian follicular development.


Assuntos
Bovinos , Fator 9 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismo , Animais , Regulação para Baixo , Feminino , Análise Serial de Proteínas , Regulação para Cima
3.
Domest Anim Endocrinol ; 59: 90-99, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28040605

RESUMO

Abundance of G protein-coupled receptor 34 (GPR34) mRNA is greater in granulosa cells (GCs) of cystic vs normal follicles of cattle. The present experiments were designed to determine if GPR34 mRNA in granulosa cell [GC] changes during selection and growth of dominant follicles in cattle as well as to investigate the hormonal regulation of GPR34 mRNA in bovine GC in vitro. In Exp. 1, estrous cycles of nonlactating cows were synchronized and then ovariectomized on either day 3-4 or 5-6 after ovulation. GPR34 mRNA abundance in GC was 2.8- to 3.8-fold greater (P < 0.05) in small (1-5 mm) and large (≥8 mm) estrogen-inactive dominant follicles than in large estrogen-active follicles. Also, GPR34 mRNA tended to be greater (P < 0.10) in F2 than F1 follicles on day 3-4 postovulation. In Exp. 2-7, ovaries were collected at an abattoir and GC were isolated and treated in vitro. Expression of GPR34 was increased (P < 0.05) 2.2-fold by IGF1. Tumor necrosis factor (TNF)-α decreased (P < 0.05) the IGF1-induced GPR34 mRNA abundance in small-follicle GC, whereas IGF1 decreased (P < 0.05) GPR34 expression by 45% in large-follicle GC. Treatment of small-follicle GC with either IL-2, prostaglandin E2 or angiogenin decreased (P < 0.05) GPR34 expression, whereas FSH, cortisol, wingless 3A, or hedgehog proteins did not affect (P > 0.10) GPR34 expression. In Exp. 6 and 7, 2 presumed ligands of GPR34, L-a-lysophosphatidylserine (LPPS) and LPP-ethanolamine, increased (P < 0.05) GC numbers and estradiol production by 2-fold or more in small-follicle GC, and this response was only observed in IGF1-treated GC. In conclusion, GPR34 is a developmentally and hormonally regulated gene in GC, and its presumed ligands enhance IGF1-induced proliferation and steroidogenesis of bovine GC.


Assuntos
Bovinos/fisiologia , Células da Granulosa/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Receptores de Lisofosfolipídeos/metabolismo , Animais , Células Cultivadas , Citocinas/farmacologia , Feminino , Regulação da Expressão Gênica/fisiologia , Células da Granulosa/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Lisofosfolipídeos/genética
4.
Animal ; 11(5): 811-819, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27760586

RESUMO

Angiogenin is a member of the ribonuclease A superfamily of proteins that has been implicated in stimulating angiogenesis but whether angiogenin can directly affect ovarian granulosa or theca cell function is unknown. Therefore, the objective of these studies was to determine the effect of angiogenin on proliferation and steroidogenesis of bovine granulosa and theca cells. In experiments 1 and 2, granulosa cells from small (1 to 5 mm diameter) follicles and theca cells from large (8 to 22 mm diameter) follicles were cultured to evaluate the dose-response effect of recombinant human angiogenin on steroidogenesis. At 30 and 100 ng/ml, angiogenin inhibited (P0.10) granulosa cell estradiol production or theca cell progesterone production, and did not affect numbers of granulosa or theca cells. In experiments 3 and 4, granulosa and theca cells from both small and large follicles were cultured with 300 ng/ml of angiogenin to determine if size of follicle influenced responses to angiogenin. At 300 ng/ml, angiogenin increased large follicle granulosa cell proliferation but decreased small follicle granulosa cell progesterone and estradiol production and large follicle theca cell progesterone production. In experiments 5 and 6, angiogenin stimulated (P<0.05) proliferation and DNA synthesis in large follicle granulosa cells. In experiment 7, 300 ng/ml of angiogenin increased (P<0.05) CYP19A1 messenger RNA (mRNA) abundance in granulosa cells but did not affect CYP11A1 mRNA abundance in granulosa or theca cells and did not affect CYP17A1 mRNA abundance in theca cells. We conclude that angiogenin appears to target both granulosa and theca cells in cattle, but additional research is needed to further understand the mechanism of action of angiogenin in granulosa and theca cells, as well as its precise role in folliculogenesis.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Células da Granulosa/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ribonuclease Pancreático/administração & dosagem , Células Tecais/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Folículo Ovariano/crescimento & desenvolvimento
5.
J Dairy Sci ; 99(11): 9143-9151, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27614836

RESUMO

Fibroblast growth factor 9 (FGF9) has been suggested to act as an antidifferentiation factor in cattle by reducing steroidogenesis and increasing cell proliferation in granulosa (GC) and theca (TC) cells. The objective of this study was to characterize FGF9 mRNA abundance in GC and TC during development of dominant follicles in dairy cattle. Estrous cycles of nonlactating dairy cattle were synchronized, and ovaries were collected on either d 3 to 4 (n=8) or 5 to 6 (n=8) postovulation for GC and TC RNA extraction from small (1-5mm), medium (5.1-8mm), and large (8.1-18mm) follicles for PCR analysis. The FGF9 mRNA abundance was greater in GC than in TC. In GC, FGF9 mRNA abundance was greater in small, medium, and large estrogen-inactive [i.e., concentrations of estradiol (E2)P4) follicles at both early (d 3-4) and late (d 5-6) growing phases of first dominant follicle. Abundance of FGF9 mRNA increased in medium-sized follicles from early to late growing phase of the dominant follicle. In TC, FGF9 mRNA abundance was greater in large E2-inactive follicles than in large E2-active follicles on d 3 to 4 postovulation; no significant differences in TC FGF9 mRNA existed among follicle types on d 5 to 6 postovulation. Correlations among levels of follicular fluid hormones and FGF9 mRNA levels revealed significant negative correlations between GC FGF9 mRNA abundance and follicular fluid E2 (r=-0.68), free IGF-1 (r=-0.63), and E2-to-P4 ratio (r=-0.58). In summary, abundance of FGF9 mRNA in GC and TC increases in medium-sized follicles during development of dominant follicles and is less in dominant E2-active than subordinate E2-inactive follicles, suggesting that FGF9 signaling could contribute to normal follicle development and steroidogenesis in dairy cattle.


Assuntos
Fator 9 de Crescimento de Fibroblastos , Células Tecais , Animais , Bovinos , Estradiol , Feminino , Células da Granulosa/metabolismo , Folículo Ovariano/química , Progesterona , RNA Mensageiro/metabolismo
6.
Domest Anim Endocrinol ; 55: 32-40, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26773365

RESUMO

Brain ribonuclease (BRB) is a member of the ribonuclease A superfamily that is constitutively expressed in a range of tissues and is the functional homolog of human ribonuclease 1. This study was designed to characterize BRB gene expression in granulosa cells (GCs) during development of bovine dominant ovarian follicles and to determine the hormonal regulation of BRB in GCs. Estrous cycles of Holstein cows (n = 18) were synchronized, and cows were ovariectomized on either day 3 to 4 or day 5 to 6 after ovulation during dominant follicle growth and selection. Ovaries were collected, follicular fluid (FFL) was aspirated, and GCs were collected for RNA isolation and quantitative polymerase chain reaction. Follicles were categorized as small (1-5 mm; pooled per ovary), medium (5-8 mm; individually collected), or large (8.1-17 mm; individually collected) based on surface diameter. Estradiol (E2) and progesterone (P4) levels were measured by radioimmunoassay (RIA) in FFL. Abundance of BRB messenger RNA (mRNA) in GCs was 8.6- to 11.8-fold greater (P < 0.05) in small (n = 31), medium (n = 66), and large (n = 33) subordinate E2-inactive (FFL E2 < P4) follicles than in large (n = 16) dominant E2-active (FFL E2 > P4) follicles. In the largest 4 follicles, GCs BRB mRNA abundance was negatively correlated (P < 0.01) with FFL E2 (r = -0.65) and E2:P4 ratio (r = -0.46). In experiment 2, GCs from large (8-22 mm diameter) and small (1-5 mm diameter) follicles were treated with insulin-like growth factor 1 (IGF1; 0 or 30 ng/mL) and/or tumor necrosis factor alpha (0 or 30 ng/mL); IGF1 increased (P < 0.05) BRB mRNA abundance, and tumor necrosis factor alpha decreased (P < 0.001) the IGF1-induced BRB mRNA abundance in large-follicle GCs. In experiment 3 to 6, E2, follicle-stimulating hormone, fibroblast growth factor 9, cortisol, wingless 3A, or sonic hedgehog did not affect (P > 0.10) abundance of BRB mRNA in GCs; thyroxine and luteinizing hormone increased (P < 0.05), whereas prostaglandin E2 (PGE2) decreased (P < 0.05) BRB mRNA abundance in small-follicle GCs. Treatment of small-follicle GCs with recombinant human RNase1 increased (P < 0.05) GCs numbers and E2 production. In conclusion, BRB is a hormonally and developmentally regulated gene in bovine GCs and may regulate E2 production during follicular growth in cattle.


Assuntos
Encéfalo/enzimologia , Regulação da Expressão Gênica/fisiologia , Células da Granulosa/metabolismo , RNA Mensageiro/metabolismo , Ribonucleases/genética , Animais , Bovinos , Estradiol/metabolismo , Feminino , Ovulação/fisiologia , Progesterona/metabolismo , RNA Mensageiro/genética
7.
J Anim Sci ; 92(2): 511-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24664559

RESUMO

The objectives of this study were to investigate the effects of fibroblast growth factor 9 (FGF9) on hormone-stimulated porcine granulosa cell proliferation and steroid production and to further elucidate the hormonal and developmental control of FGFR2IIIc gene expression in granulosa cells. Porcine ovaries were collected from a local slaughterhouse and granulosa cells were collected from small to medium (1 to 5 mm) follicles for 5 in vitro studies that were conducted. Cells were cultured for 48 h in 5% fetal calf serum plus 5% porcine serum and then treated with various combinations of FSH, IGF-I, FGF9, Sonic hedgehog (SHH), cortisol, PGE2, and/or wingless-type mouse mammary tumor virus integration site family member 5A (WNT5A) in serum-free medium for an additional 24 or 48 h. Medium was collected for analysis of steroid concentration via RIA, or RNA was collected for gene expression analysis of FGFR2IIIc via quantitative reverse transcription PCR. Fibroblast growth factor 9 stimulated (P < 0.05) IGF-I-induced estradiol production in the presence of FSH and testosterone. However, FGF9 had inconsistent effects on progesterone production, stimulating progesterone production in the presence of FSH and testosterone but inhibiting progesterone production in the presence of IGF-I, FSH, and testosterone. Cell numbers were increased (P < 0.05) by FGF9 in the presence of IGF-I and FSH but not in the presence of FSH and absence of IGF-I. For FGFR2IIIc mRNA studies, granulosa cells were treated with FSH, IGF-I, FGF9, SHH, cortisol, PGE2, or WNT5A. Follicle-stimulating hormone alone had no effect (P > 0.10) whereas IGF-I increased (P < 0.05) FGFR2IIIc mRNA abundance. Cortisol, PGE2, SHH, and WNT5A had no effect (P > 0.10) on FGFR2IIIc gene expression whereas FGF9 in the presence of FSH and IGF-I inhibited (P < 0.05) FGFR2IIIc gene expression. In an in vivo study, granulosa cells from large (7 to 14 mm) follicles had greater (P < 0.05) abundance of FGFR2IIIc mRNA than small (1 to 3 mm) or medium (4 to 6 mm) follicles. In conclusion, IGF-I-induced FGFR2IIIc mRNA may be a mechanism for increased responses to FGF9 in FSH plus IGF-I-treated granulosa cells. Fibroblast growth factor 9 and IGF-I may work together as amplifiers of follicular growth and granulosa cell differentiation by stimulating estradiol production and concomitantly stimulating granulosa cell growth in pigs.


Assuntos
Fator 9 de Crescimento de Fibroblastos/metabolismo , Células da Granulosa/metabolismo , RNA Mensageiro/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Suínos/fisiologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Fator 9 de Crescimento de Fibroblastos/genética , Hormônio Foliculoestimulante/farmacologia , Regulação da Expressão Gênica , Proteínas Hedgehog/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , RNA Mensageiro/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética
8.
J Endocrinol ; 215(1): 167-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22872763

RESUMO

Fibroblast growth factor 9 (FGF9) protein affects granulosa cell (GC) function but is mostly localized to theca cell (TC) and stromal cell of rat ovaries. The objectives of this study were to determine the 1) effects of FGF9 on TC steroidogenesis, gene expression, and cell proliferation; 2) mechanism of action of FGF9 on TCs; and 3) hormonal control of FGF9 mRNA expression in TCs. Bovine ovaries were collected from a local slaughterhouse and TCs were collected from large (8-22 mm) follicles and treated with various hormones in serum-free medium for 24 or 48 h. FGF9 caused a dose-dependent inhibition (P<0·05) of LH- and LH+IGF1-induced androstenedione and progesterone production. Also, FGF9 inhibited (P<0·05) LH+IGF1-induced expression of LHCGR, CYP11A1, and CYP17A1 mRNA (via real-time RT-PCR) in TCs. FGF9 had no effect (P>0·10) on STAR mRNA abundance. Furthermore, FGF9 inhibited dibutyryl cAMP-induced progesterone and androstenedione production in LH+IGF1-treated TCs. By contrast, FGF9 increased (P<0·05) the number of bovine TCs. Abundance of FGF9 mRNA in GCs and TCs was several-fold greater (P<0·05) in small (1-5 mm) vs large follicles. Tumor necrosis factor α and WNT5A increased (P<0·05) abundance of FGF9 mRNA in TCs. In summary, expression of FGF9 mRNA in TCs is developmentally and hormonally regulated. FGF9 may act as an autocrine regulator of ovarian function in cattle by slowing TC differentiation via inhibiting LH+IGF1 action via decreasing gonadotropin receptors and the cAMP signaling cascade while stimulating proliferation of TCs.


Assuntos
Fator 9 de Crescimento de Fibroblastos/genética , Fator 9 de Crescimento de Fibroblastos/farmacologia , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismo , Animais , Bovinos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fator 9 de Crescimento de Fibroblastos/metabolismo , Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Esteroides/biossíntese , Células Tecais/citologia , Células Tecais/fisiologia
9.
Youth Soc ; 25(1): 75-92, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12156362

RESUMO

PIP: Logistic regressions were used to analyze consistency in decision making about adoption and parenting among 162 pregnant adolescents aged 12-23 years in a Crittenton Services facility. Eight hypotheses were generated about the determinants of adoption or parenting. For instance, external locus of control and lower self-esteem were expected to lower the odds of being consistent in planning for adoptions. Significant others' influence in support of adoption increases the odds of consistency. Residents have the opportunity to participate in small group educational efforts which emphasize adoption as a viable alternative and receive general counseling help in planning a realistic postpartum plan for parenting. Age, ethnicity, education, and reproductive history were considered background variables. Nowicki and Strickland's Control Scale for Children, Coopersmith's Self-Esteem Inventory, and McMaster's Family Assessment Device were used to measure social psychological variables. Social influence measures pertained to communication with and preference of the mother and the birth father. The dependent measures were the initial adoption plan and consistency with or switching of the initial adoption plan. The results reveal that equal numbers initially planned to adopt and to parent. Each group had similar background characteristics, with the exception that most adoption acceptors lived at home, and those who chose parenting were in the custody of a public agency. About 20% switched decisions over time. One teenager switched from parenting to adoption, and 32 (19.8%) switched from adoption to parenting. Of the 16 predictors, only social influence variables had clear significant effects. Mother's preference for adoption was the strongest influence on decision making. Only the birth father's preference strongly influenced the plan to adopt, by tripling the odds of consistency of adoption. Agreement between the mother and the birth father on adoption increased the odds of a consistent adoption plans. In the multivariate models, only birth father's influence remained adequately significant.^ieng


Assuntos
Adoção , Atitude , Coleta de Dados , Tomada de Decisões , Lares para Grupos , Conhecimento , Grupo Associado , Gravidez na Adolescência , Psicologia , Autoimagem , Fatores Socioeconômicos , América , Comportamento , Educação Infantil , Comunicação , Demografia , Países Desenvolvidos , Economia , Fertilidade , Geografia , Conhecimentos, Atitudes e Prática em Saúde , Habitação , América do Norte , Percepção , População , Dinâmica Populacional , Pesquisa , Características de Residência , Estudos de Amostragem , Comportamento Sexual , Estados Unidos
10.
Child Welfare ; 68(1): 45-55, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2914518

RESUMO

Profiles on three groups of pregnant teens in a comprehensive social service agency were identified: those who followed through with a parenting plan, those who followed through with an adoption plan, and those who switched from an adoption plan to a parenting plan. Pregnant teens who switched plans were identified as high risk in terms of health histories and psychosocial profiles. Since they represent as much as one-third of the total population, service plans must be made for them that focus on these risk areas. This article addresses the identification of new subgroups in the universe of pregnant teenagers, and treatment implications.


Assuntos
Adoção , Tomada de Decisões , Gravidez na Adolescência , Adolescente , Adulto , Criança , Feminino , Nível de Saúde , Humanos , Saúde Mental , Gravidez , Fatores de Risco , Serviço Social
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