RESUMEN

Final antral follicle development and future ovulation are mediated by gonadotropin-induced changes with spatio-temporally regulated expression of genes. Here, we aimed to quantify the relative mRNA abundance of bta-miR-222 and its predicted target, LHCGR, in granulosa cells (GCs) from follicles, after follicle deviation, as well as from GCs cultured in vitro with follicle stimulating hormone (FSH) and/or insulin. Thus, to study the impact of follicle deviation, Nelore heifers (n = 10; Bos taurus indicus) were hormonally synchronized and slaughtered 3 days after ovulation. Then, GCs from the dominant follicle (DF) and its respective subordinate follicle (SF) were recovered for RT-qPCR. For in vitro analysis, small follicles (2-5 mm) were dissected from bovine ovaries collected from a local abattoir. The GCs were isolated and cultured in serum-free medium, or treated with insulin (1 ng/mL or 10 ng/mL) alone or in combination with human recombinant FSH (1 ng/mL), for 6 days. Our findings showed that the relative mRNA abundance of LHCGR in GCs was higher in the DF compared to the SF (p = 0.01). Inversely, bta-miR-222 expression was lower in the DF compared to the SF (p = 0.01). Furthermore, GCs cultured with FSH and insulin together resulted in a higher abundance of LHCGR and a lower abundance of bta-miR-222 (p ≤ 0.05) when compared to GCs cultured with insulin alone. In conclusion, we found that the LHCGR upregulation in GCs from the DF is inversely related to bta-miR-222 expression. We also suggest the involvement of FSH in bta-miR-222 suppression in healthy bovine GCs.

Asunto(s)

Hormona Folículo Estimulante , MicroARNs , Animales , Bovinos , Células Cultivadas , Femenino , Hormona Folículo Estimulante/metabolismo , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/metabolismo , Insulina/metabolismo , Insulina/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Folículo Ovárico

RESUMEN

The objective was to investigate effects of progesterone (P4) dose on abundance of luteinizing hormone receptor (LHCGR), aromatase (CYP19A1), 3ß-hydroxysteroid dehydrogenase (HSD3B1), and other steroidogenic mRNA transcripts in granulosa cells from dominant follicles. Nellore heifers were assigned to one of six groups: new, first-use controlled internal drug release device (CIDR1) inserted for 5 days (Large-P4-dose-D5; n = 7) or 6 days (Large-P4-dose-D6; n = 8), prostaglandin (PG)F2α administered on D0 and 1 previously-used CIDR (CIDR3) inserted for 5 days (Small- P4-dose-D5; n = 8) or 6 days (Small-P4-dose-D6; n = 8), CIDR1 inserted on D0 and removed plus PGF2α on D5 (Large-P4-dose-proestrus (PE); n = 7), and CIDR3 and PGF2α on D0 and 1, CIDR3 removed plus PGF2α on D5 (Small-P4-dose-PE; n = 7). Duration of P4 treatment (D5 compared to D6) affected abundances of CYP19A1 mRNA transcripts, with there being greater abundances on D6 than D5 (P ≤ 0.05). Heifers treated with the large dose of P4 had a smaller dominant follicle, less serum and intra-follicular estradiol (E2) concentrations (P ≤ 0.05) and lesser LHCGR, CYP19A1, and HSD3B1 transcript abundances (P ≤ 0.05). Heifers treated to induce PE had a larger follicle diameter (P = 0.09), greater intra-follicular E2 concentrations and larger abundances of CYP19A1 mRNA transcript (P ≤ 0.05) than heifers of the D6 group. Overall, treatment with larger doses of P4 resulted in lesser abundances of LHCGR, HSD3B1, and CYP19A1 mRNA transcripts; thus, potentially leading to development of smaller dominant follicles and lesser E2 concentrations.

Asunto(s)

Bovinos , Sincronización del Estro/efectos de los fármacos , Progesterona/farmacología , Receptores de HL/metabolismo , Animales , Aromatasa/genética , Aromatasa/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Dinoprost/administración & dosificación , Dinoprost/análogos & derivados , Dinoprost/farmacología , Estradiol/administración & dosificación , Estradiol/análogos & derivados , Estradiol/farmacología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Células de la Granulosa/efectos de los fármacos , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Progesterona/administración & dosificación , Progesterona Reductasa/genética , Progesterona Reductasa/metabolismo , Receptores de HL/genética , Esteroide Isomerasas/genética , Esteroide Isomerasas/metabolismo

RESUMEN

Addition effects of insulin-like growth factor-1 (IGF-1) and its synthetic analogue insulin-like growth factor-1 recombinant-3 (LongR3-IGF-1) after in vitro maturation (IVM) of cattle cumulus-oocyte complexes (COCs) were compared and evaluated on meiotic progression, apoptosis and profile genes of oocyte competence (GDF9, BMP15, BAX, BCL2, OOSP1, IGFBP2, IGBFP4 and IGFBP5), and their respective cumulus cells (AREG, EGFR, FSHR, COX2, BAX, BCL2, IGFBP2, IGFBP4 and IGFBP5). The 739 COCs (n = 10 pools) of bovine ovaries were collected, selected and matured with IGF-1 (100 ng/mL), LongR3-IGF-1 (100 ng/mL), and in two control groups with 0.1% polyvinyl alcohol (PVA) or 10% fetal bovine serum (FBS), for 22-24 h. The statistical analysis was performed by a linear mixed effects model, ANOVA and Tukey tests. There was no statistical difference between experimental groups taken into account the meiotic progression and apoptosis (P > 0.05). Nevertheless, there were statistical differences (P ≤ 0.05) among FBS, IGF-1 and LongR3-IGF-1 groups for IGFBP4 gene expression, and among PVA, IGF-1 and LongR3-IGF-1 for COX2 gene expression in cumulus cells. Moreover, statistical difference was found for BCL2 gene expression between IGF-1, FBS and PVA groups and for IGFBP4 gene expression between LongR3-IGF-1, PVA and FBS in oocytes. There was no statistical difference between experimental groups for other genes evaluated. These results showed a good performance of IVM of bovine oocytes in the presence of LongR3-IGF-1 and the possibility of replacement of IGF-1 and FBS.

Asunto(s)

Células del Cúmulo/efectos de los fármacos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Factor I del Crecimiento Similar a la Insulina/farmacología , Oocitos/efectos de los fármacos , Proteínas Recombinantes/farmacología , Animales , Bovinos , Femenino

RESUMEN

Our objectives were to investigate potential changes in the size of steroidogenic large luteal cells (LLC) during partial luteolysis induced by a sub-dose of cloprostenol in early diestrus and to determine transcriptional variations in genes involved in corpus luteum (CL) functions. Cows were subjected to an Ovsynch protocol, with the time of the second GnRH treatment defined as Day 0 (D0). On D6, cows were randomly allocated into three treatments: Control (2 mL saline, im; n = 10), 2XPGF (two doses of 500 µg of cloprostenol, im, 2 h apart; n = 8) or 1/6PGF (single dose of 83.3 µg of cloprostenol, im; n = 10). Before treatments and every 8 h during the 48-h experimental period, blood samples were collected and CL volumes measured. Furthermore, two CL biopsies were obtained at 24 and 40 h post-treatment. The 1/6PGF treatment caused partial luteolysis, characterized by sudden decreases in plasma progesterone (P4) concentrations, luteal volume and LLC size, followed by increases (to pretreatment values) in P4 and luteal volume at 24 and 40 h post-treatment, respectively. However, at the end of the study, P4, luteal volume and LLC size were all significantly smaller than in Control cows. Temporally associated with these phenotypes, there was a lower mRNA abundance of VEGFA at 24 and 40 h, and ABCA1 at 24 h (P < 0.05). In conclusion, a sudden reduction in CL size during partial luteolysis induced by a sub-dose of PGF2α analog on day 6 of the estrous cycle was attributed to a reduction in LLC size, although these changes did not account for the entire phenomenon. In addition to its involvement in reducing CL size, decreased VEGFA mRNA abundance impaired CL development, resulting in a smaller luteal gland and lower plasma P4 concentrations compared to Control cows.

Asunto(s)

Células Lúteas , Luteólisis , Animales , Bovinos , Cuerpo Lúteo , Diestro , Dinoprost , Femenino , Progesterona

RESUMEN

To better understand the impact of ovarian superstimulation on bovine follicular microenvironment, Nelore cows (Bos taurus indicus) were subjected to ovarian superstimulation with follicle stimulating hormone (FSH, n = 10; P-36 protocol) or FSH combined with eCG (n = 10; P-36/eCG protocol). Follicular fluid was analyzed for cholesterol concentration. Granulosa cells were analyzed by RT-qPCR to assess the expression of genes involved in steroidogenic and ovulatory and expression of microRNAs involved in final follicular development and luteinizing hormone/choriogonadotropin receptor (LHCGR) expression. Plasma concentration of estradiol was also measured. Follicular fluid from the P-36 group showed higher concentration of cholesterol than that of control (non-superstimulated) cows. Plasma concentration of estradiol was higher in the P-36/eCG group. Abundance of STAR and FSHR mRNAs were lower in granulosa cells from the P-36/eCG group. In contrast, LHCGR mRNA abundance was higher in superstimulated granulosa cells from the P-36 group and showed a pattern opposite to that of miR-222 expression. Ovarian superstimulation did not affect the expression of other markers (mmu-miR-202-5p, has-miR-873, has-miR-144, and their target genes, CREB, TGFBR2, and ATG7) of antral follicle development. However, the mRNA expression of VEGF pathway components was modulated by P-36 treatment. Taken together, these results demonstrate that superstimulatory protocols modify steroidogenic capacity, increase plasma estradiol, and regulate the abundance of VEGF system, LHCGR mRNA and suppress the expression of miR-222 in bovine granulosa cells.

Asunto(s)

Bovinos/genética , Hormonas Esteroides Gonadales/biosíntesis , MicroARNs/genética , Ovulación/genética , Superovulación/genética , Animales , Sincronización del Estro/fisiología , Femenino , Expresión Génica , Redes y Vías Metabólicas/genética , Inducción de la Ovulación/métodos , Inducción de la Ovulación/veterinaria , Superovulación/fisiología

RESUMEN

Ovarian superstimulation with exogenous gonadotropins has been extensively used to produce in vivo-derived embryos for embryo transfer in cattle. This process modifies the antral follicle microenvironment and affects oocyte and embryo quality as well the differentiation of granulosa cells. Lipids play significant roles in the cell, such as energy storage, cell structure, and fine-tuning of the physical properties and functions of biological membranes. The phospholipid (PL) contents as well as the effects of superstimulatory treatments on the PL profile of follicular fluid from cows, however, remain unknown. Therefore, to gain insight into the effects of superstimulation with follicle-stimulating hormone (FSH; P-36 protocol) or FSH combined with equine chorionic gonadotropin (eCG; P-36/eCG protocol) on the profile and abundance of PL from cows submitted or not submitted to superstimulatory protocols, were treated with these two superstimulatory protocols. As a control, non-superstimulated cows were only submitted to estrous synchronization. The follicular fluid was aspirated, the remaining cells removed and the follicular fluid stored at -80 °C until extraction. The lipid screening was performed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and this technique allowed the identification of sphingomyelins (SM) and phosphatidylcholines (PC) and phosphoethanolamines (PE). The relative abundance of the ions observed in the three experimental groups was analyzed by multivariate and univariate statistical models. The phospholipid SM (16:0) and PC (36:4) and/or PC (34:1) were less (P < 0.05) abundant in the P-36 group compared to the control or P-36/eCG groups. However, the PC (34:2) was more (P < 0.05) abundant in both group of superstimulated cows compared to the control. In summary, ovarian superstimulation seems to modulate the PL content of bovine follicular fluid with a significant increase in PC (34:2), which jointly with others PC and SM, seems to offer a suitable biomarker involved with reproductive processes successful as ovary superstimulation response and embryo development.

Asunto(s)

Bovinos/metabolismo , Líquido Folicular/metabolismo , Metabolismo de los Lípidos , Inducción de la Ovulación/veterinaria , Animales , Femenino , Gonadotropinas/uso terapéutico , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/metabolismo , Inducción de la Ovulación/métodos

RESUMEN

The present study determined the transcriptome profile in Nelore and Holstein oocytes subjected to heat shock during IVM and the mRNA abundance of selected candidate genes in Nelore and Holstein heat-shocked oocytes and cumulus cells (CC). Holstein and Nelore cows were subjected to in vivo follicle aspiration. Cumulus-oocyte complexes were assigned to control (38.5°C, 22h) or heat shock (41°C for 12h, followed by 38.5°C for 10h) treatment during IVM. Denuded oocytes were subjected to bovine microarray analysis. Transcriptome analysis demonstrated 127, nine and six genes were differentially expressed between breed, temperature and the breed×temperature interaction respectively. Selected differentially expressed genes were evaluated by real-time polymerase chain reaction in oocytes and respective CC. The molecular motor kinesin family member 3A (KIF3A) was upregulated in Holstein oocytes, whereas the pro-apoptotic gene death-associated protein (DAP) and the membrane trafficking gene DENN/MADD domain containing 3 (DENND3) were downregulated in Holstein oocytes. Nelore CC showed increased transcript abundance for tight junction claudin 11 (CLDN11), whereas Holstein CC showed increased transcript abundance for antioxidant metallothionein 1E (MT1E) . Moreover, heat shock downregulated antioxidant MT1E mRNA expression in CC. In conclusion, oocyte transcriptome analysis indicated a strong difference between breeds involving organisation and cell death. In CC, both breed and temperature affected mRNA abundance, involving cellular organisation and oxidative stress.

Asunto(s)

Proteínas Reguladoras de la Apoptosis/metabolismo , Células del Cúmulo/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Respuesta al Choque Térmico/genética , Cinesinas/metabolismo , Oocitos/metabolismo , Transcriptoma , Animales , Proteínas Reguladoras de la Apoptosis/genética , Bovinos , Regulación hacia Abajo , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido/genética , Calor , Cinesinas/genética , Regulación hacia Arriba

RESUMEN

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 wave and the future dominant and future subordinate follicles were identified based on diameter and cytochrome P450, family 19, subfamily A, polypeptide 1 (CYP19A1) mRNA levels in granulosa cells. Theca cells of the future dominant follicle contained less mRNA encoding FGF7 and FGF10 compared with those from the future subordinate follicle 2.5 days after ovulation, before a significant difference between the diameters of the future dominant and future subordinate follicles could be observed, but FGF22 mRNA levels did not change. Levels of mRNA encoding FGF receptors FGFR1B and FGFR2B in theca and granulosa cells, respectively, were lower in the future dominant follicle compared with the future subordinate follicle. Addition of FGF10 to granulosa cells in vitro significantly decreased oestradiol secretion, as well as CYP19A1, FSH receptor (FSHR) and insulin-like growth factor 1 receptor (IGF1R) mRNA abundance, whereas FGF22 had no effect. We conclude that FGF10 and FGFR2B expression is increased in the future subordinate follicle before morphological deviation, which may contribute to follicle selection.

Asunto(s)

Factor 10 de Crecimiento de Fibroblastos/metabolismo , Folículo Ovárico/metabolismo , Ovario/metabolismo , Ovulación/metabolismo , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Animales , Bovinos , Femenino , Factor 10 de Crecimiento de Fibroblastos/farmacología , Hormona Folículo Estimulante/metabolismo , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Folículo Ovárico/efectos de los fármacos , Ovario/efectos de los fármacos , Ovulación/efectos de los fármacos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptores de HFE/metabolismo , Células Tecales/efectos de los fármacos , Células Tecales/metabolismo

RESUMEN

The time at which follicles acquire LHR in bovine granulosa cells is the subject of some controversy among researchers. The main objective of the present study was to assess the mRNA expression of LHR and LRBP (mRNA protein binding), a post-transcriptional suppressor of LHR mRNA expression, in granulosa cells from the two largest follicles around the expected time of follicle deviation in Nelore heifers. First, the interval between ovulation and follicle deviation in 20 Nelore heifers was determined (2.3 ± 0.2 days after ovulation). Ovulation was hormonally synchronized, and then, heifers were slaughtered on days 2, 2.5 and 3 after ovulation (before, during and after, respectively, the expected time of follicle deviation), and granulosa cells from the two largest follicles were collected. The mRNA abundance of an LHR fragment common to all isoforms (total LHR) and LRBP was assessed by real-time RT-PCR, and LHR alternative transcripts were assessed by semiquantitative RT-PCR followed by electrophoresis. LHR mRNA expression was not detected before the expected time of deviation. Total LHR mRNA abundance was greater in the largest follicle and increased from day 2.5 to 3. In contrast, LRBP mRNA was detected starting on day 2 and was more expressed in the second largest follicle on days 2.5 and 3. The present data suggest that the expression of LHR mRNA in bovine granulosa cells is established after follicle deviation and that the lower abundance of LRBP mRNA after the expected time of deviation may contribute to greater expression of LHR in the bovine dominant follicle.

Asunto(s)

Bovinos/genética , Células de la Granulosa/metabolismo , Folículo Ovárico/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Receptores de HL/genética , Animales , Femenino , Expresión Génica , Ovulación/genética , ARN Mensajero/genética , Transducción de Señal/genética

RESUMEN

Many peptides are responsible for the coordination of muscle contraction, secretion and ciliary beating of the oviduct epithelium to allow the transport of gametes and embryos, including vascular endothelial growth factors (VEGF), prostaglandins (PGs), endotelin-1 (ET-1) and angiotensin II (Ang II). The effect of reproductive biotechnologies used to improve embryo yield on oviduct gene expression is poorly understood. Thus, the aim of the present study was to evaluate the effect of ovarian superstimulation on the mRNA expression of the genes encoding the major peptides involved in oviduct contraction in bovine. Therefore, Nelore cows were submitted to P-36 (n=5) or P-36/eCG (n=5) ovarian superstimulatory protocols and a control group of cows was not submitted to any superstimulatory protocol (n=5). The relative expression of VEGF (VEGF, Flk1, Flt1), Ang II (AGTR2, ACE1), ET1 (ET1, ECE1) and PG pathway members (PGES, EP2, EP4, COX1, COX2) was analyzed using real time RT-PCR in each of oviduct segment (infundibulum, ampulla and isthmus). All target genes were expressed in the three segments of the bovine oviduct; however, specific genes were regulated by ovarian superstimulation: EP2 and EP4 receptors mRNA was affected by P-36/eCG protocol, in the ampulla and infundibulum, respectively; and AGTR2 mRNA was up-regulated by both the P-36/eCG and P-36 protocols in the isthmus. The upregulation of EP2, EP4 and AGTR2 expression in the superstimulated cows suggests a suitable effect of FSH and eCG on bovine oviduct physiology, coordinating the contraction in Nelore cows.

Asunto(s)

Trompas Uterinas/metabolismo , Receptor de Angiotensina Tipo 2/genética , Subtipo EP2 de Receptores de Prostaglandina E/genética , Subtipo EP4 de Receptores de Prostaglandina E/genética , Superovulación , Animales , Bovinos , Trompas Uterinas/efectos de los fármacos , Femenino , Gonadotropinas Equinas/farmacología , ARN Mensajero/metabolismo , Receptor de Angiotensina Tipo 2/metabolismo , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Superovulación/genética , Superovulación/metabolismo

RESUMEN

The LH plays a key role in controlling physiological processes in the ovary acting via LH receptor (LHR). In general, the effects of LHR on the regulation of granulosa cell differentiation are mediated mainly via the Gs-protein/adenylyl cyclase/cAMP system; however, the LHR activation could also induce phospholipase C (PLC)/inositol trisphosphate (IP3) via Gq/11 system. Additionally, the expression of G-proteins (GNAS, GNAQ, and GNA11) and PLC ß has been showed in bovine antral follicle, concomitant with an increase in LHR expression. To gain insight into the effects of superstimulation with FSH (P-36 protocol) or FSH combined with equine chorionic gonadotropin (eCG; P-36/eCG protocol) on the mRNA expression of proteins involved in LHR signaling in bovine granulosa cells, Nelore cows (Bos indicus) were treated with two superstimulatory protocols: P-36 protocol or P-36/eCG protocol (replacement of the FSH by eCG administration on the last day of treatment). Nonsuperstimulated cows were only submitted to estrous synchronization without ovarian superstimulation. The granulosa cells were harvested from follicles and mRNA abundance of GNAS, GNAQ, GNA11, PLCB1, PLCB, PLCB4, and adenylyl cyclase isoforms (ADCY3, ADCY4, ADCY6, ADCY8, and ADCY9) was measured by real-time reserve transcription followed by polymerase chain reaction. No differences on mRNA abundance of target genes were observed in granulosa cells of cows submitted to P-36 protocol compared with control group. However, the cows submitted to P-36/eCG protocol showed upregulation on the mRNA abundance of target genes (except ADCY8) in granulosa cells. Although the P-36 protocol did not regulate mRNA expression of the proteins involved in the signaling mechanisms of the cAMP and IP3 systems, the constant presence of GNAS, GNAQ, GNA11, PLCB1, PLCB3, PLCB4, and adenylyl cyclase isoforms (ADCY3, ADCY4, ADCY6, and ADCY9) mRNA and the upregulation of these genes in granulosa cells from cows submitted to P-36/eCG protocol reinforce the participation of Gq/11/PLC/IP3 signaling as well as Gs-protein/adenylyl cyclase/cAMP system on LHR pathways during bovine granulosa cell differentiation submitted to superstimulatory treatments.

Asunto(s)

Bovinos/metabolismo , Gonadotropina Coriónica/farmacología , Hormona Folículo Estimulante/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Inducción de la Ovulación/veterinaria , Receptores de HL/metabolismo , Animales , Femenino , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Caballos , Inducción de la Ovulación/métodos , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos

RESUMEN

In the mammalian ovary, FGF10 is expressed in oocytes and theca cells and is a candidate for paracrine signaling to the developing granulosa cells. To gain insight into the participation of FGF10 in the regulation of fetal folliculogenesis, we assessed mRNA expression patterns of FGF10 and its receptors, FGFR1B and FGFR2B, in relation to fetal follicle dynamics and localized FGF10 protein in bovine fetal ovaries at different ages. Primordial, primary, secondary, and antral follicles were first observed on Days 75, 90, 150, and 210 of gestation, respectively. The levels of GDF9 and BMP15 mRNA, markers for primordial and primary follicles, respectively, increased during fetal ovary development in a consistent manner with fetal follicle dynamics. CYP17A1 mRNA abundance increased from Day 60 to Day 75 and then from Day 120 to Day 150, coinciding with the appearance of secondary follicles. FGF10 mRNA abundance increased from Day 90, and this increase was temporally associated with increases in FGFR1B mRNA abundance and in the population of primary follicles. In contrast, FGFR2B mRNA expression was highest on Day 60 and decreased thereafter. FGF10 protein was localized to oogonia and oocytes and surrounding granulosa cells at all fetal ages. The present data suggest a role for FGF10 in the control of fetal folliculogenesis in cattle.

Asunto(s)

Bovinos/embriología , Factor 10 de Crecimiento de Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Ovario/embriología , Animales , Femenino , Factor 10 de Crecimiento de Fibroblastos/genética , Ovario/metabolismo , Receptores de Factores de Crecimiento de Fibroblastos/genética , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo

RESUMEN

The IGF system is related to embryo quality. We aim to determine the effect of the heat stress on the mRNA expression of IGF1 and IGF2, IGFR1 and IGFR2, IGFBP2 and IGFBP4, and PAPPA in in vitro production (IVP) blastocysts from Nelore and Holstein after ovum pick up (OPU) to better understand the differences between these breeds. Oocytes from four Nelore and seven Holstein were collected in six OPU sessions. Following in vitro maturation and fertilization using six Nelore or Holstein sires, embryos were divided into control (cultured at 39°C) and heat stress (HS; exposed to 41°C for 9 h). Blastocysts were submitted to RNA extraction. The IGF1 expression was higher in blastocysts under HS in both breeds, and the expression of IGFBP2 and IGFBP4 was higher in Holstein blastocysts under HS. The high PAPPA expression and the low expression of IGFBP2 and IGFBP4 are associated with a more efficient degradation of IGFBPs, which results in greater IGF bioavailability in Nelore blastocysts and may contribute to the superior HS tolerance in Nelore, when compared to Holstein.

Asunto(s)

Bovinos/genética , Bovinos/fisiología , Técnicas de Cultivo de Embriones/veterinaria , Calor , Somatomedinas/metabolismo , Animales , Femenino , Fertilización In Vitro/veterinaria , Regulación del Desarrollo de la Expresión Génica/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Somatomedinas/genética , Especificidad de la Especie , Estrés Fisiológico/fisiología , Transcriptoma

RESUMEN

This study investigated the consequences of intrauterine protein restriction on the gastrointestinal tract and particularly on the gene expression and activity of intestinal disaccharidases in the adult offspring. Wistar rat dams were fed isocaloric diets containing 6% protein (restricted, n = 8) or 17% protein (control, n = 8) throughout gestation. Male offspring (n = 5-8 in each group) were evaluated at 3 or 16 weeks of age. Maternal protein restriction during pregnancy produced offspring with growth restriction from birth (5.7 ± 0.1 vs 6.3 ± 0.1 g; mean ± SE) to weaning (42.4 ± 1.3 vs 49.1 ± 1.6 g), although at 16 weeks of age their body weight was similar to control (421.7 ± 8.9 and 428.5 ± 8.5 g). Maternal protein restriction also increased lactase activity in the proximal (0.23 ± 0.02 vs 0.15 ± 0.02), medial (0.30 ± 0.06 vs 0.14 ± 0.01) and distal (0.43 ± 0.07 vs 0.07 ± 0.02 U·g-1·min-1) small intestine, and mRNA lactase abundance in the proximal intestine (7.96 ± 1.11 vs 2.38 ± 0.47 relative units) of 3-week-old offspring rats. In addition, maternal protein restriction increased sucrase activity (1.20 ± 0.02 vs 0.91 ± 0.02 U·g-1·min-1) and sucrase mRNA abundance (4.48 ± 0.51 vs 1.95 ± 0.17 relative units) in the duodenum of 16-week-old rats. In conclusion, the present study shows for the first time that intrauterine protein restriction affects gene expression of intestinal enzymes in offspring.

Asunto(s)

Dieta con Restricción de Proteínas , Disacaridasas/metabolismo , Regulación de la Expresión Génica/fisiología , Intestino Delgado/enzimología , Adaptación Fisiológica , Animales , Animales Recién Nacidos , Disacaridasas/análisis , Femenino , Embarazo , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa

RESUMEN

This study investigated the consequences of intrauterine protein restriction on the gastrointestinal tract and particularly on the gene expression and activity of intestinal disaccharidases in the adult offspring. Wistar rat dams were fed isocaloric diets containing 6% protein (restricted, n = 8) or 17% protein (control, n = 8) throughout gestation. Male offspring (n = 5-8 in each group) were evaluated at 3 or 16 weeks of age. Maternal protein restriction during pregnancy produced offspring with growth restriction from birth (5.7 ± 0.1 vs 6.3 ± 0.1 g; mean ± SE) to weaning (42.4 ± 1.3 vs 49.1 ± 1.6 g), although at 16 weeks of age their body weight was similar to control (421.7 ± 8.9 and 428.5 ± 8.5 g). Maternal protein restriction also increased lactase activity in the proximal (0.23 ± 0.02 vs 0.15 ± 0.02), medial (0.30 ± 0.06 vs 0.14 ± 0.01) and distal (0.43 ± 0.07 vs 0.07 ± 0.02 U·g-1·min-1) small intestine, and mRNA lactase abundance in the proximal intestine (7.96 ± 1.11 vs 2.38 ± 0.47 relative units) of 3-week-old offspring rats. In addition, maternal protein restriction increased sucrase activity (1.20 ± 0.02 vs 0.91 ± 0.02 U·g-1·min-1) and sucrase mRNA abundance (4.48 ± 0.51 vs 1.95 ± 0.17 relative units) in the duodenum of 16-week-old rats. In conclusion, the present study shows for the first time that intrauterine protein restriction affects gene expression of intestinal enzymes in offspring.

Asunto(s)

Animales , Femenino , Embarazo , Dieta con Restricción de Proteínas , Disacaridasas/metabolismo , Regulación de la Expresión Génica/fisiología , Intestino Delgado/enzimología , Adaptación Fisiológica , Animales Recién Nacidos , Disacaridasas/análisis , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa

RESUMEN

Heat stress is an important cause of poor development and low survival rates in bovine embryos. Experiments were conducted to test the hypothesis that Bos indicus embryos are more resistant to heat stress than are Bos taurus embryos. In experiment 1, Nelore and Jersey embryos from oocyte pick-up-derived oocytes were submitted to heat stress (96 hours post-insemination, 41 °C, 6 hours), developmental ratios were assessed at Day 7 (Day 0 = day of fertilization), and blastocysts were frozen for RNA extraction. Experiment 2 evaluated expression of COX2, CDX2, HSF1, and PLAC8 in previously frozen blastocysts. In experiment 3, Nellore and Angus embryos from oocyte pick-up-derived oocytes were submitted to heat stress (96 hours post-insemination, 41 °C, 12 hours) and transferred to recipients on Day 7. In experiment 4, embryos developed as in experiment 3 were fixed for Terminal deoxynucleotidyl transferase dUTP nick end labeling labeling and total cell counting. In experiment 1, heat stress decreased the percentage of Jersey oocytes that became blastocysts, but had no effect on Nellore embryos (34.6%, 25.0%, 39.5%, and 33.0% for Jersey control, Jersey heat-stressed, Nellore control, and Nellore heat-stressed oocytes, respectively; P < 0.05). In experiment 2, heat stress decreased (P < 0.05) expression of CDX2 and PLAC8, with higher expression of these genes in Nellore embryos than in Jersey embryos. Heat stress also decreased (P < 0.05) expression of COX2 in Jersey embryos, but had no effect on Nellore embryos. Expression of HSF1 was decreased (P < 0.05) by heat stress in both breeds, with a greater effect in Nellore embryos. In experiment 3, heat stress tended (P = 0.1) to decrease the percentage of pregnancies among cows (Day 30 to 35) that received Angus embryos. In experiment 4, heat stress increased (P < 0.05) the percentage of apoptotic blastomeres, but had no breed-specific effects. In addition, Nellore embryos had fewer (P < 0.05) Terminal deoxynucleotidyl transferase dUTP nick end labeling- positive blastomeres than did Angus embryos. We concluded that the detrimental effects of heat stress were dependent upon embryo breed and were more evident in Bos taurus embryos than in Bos indicus embryos.

Asunto(s)

Bovinos/embriología , Embrión de Mamíferos/fisiología , Desarrollo Embrionario/fisiología , Fertilización In Vitro/veterinaria , Calor/efectos adversos , Animales , Apoptosis , Blastocisto/fisiología , Transferencia de Embrión/veterinaria , Femenino , Expresión Génica/fisiología , Oocitos/fisiología , Especificidad de la Especie

RESUMEN

Os mecanismos que coordenam o desenvolvimento folicular ainda não são completamente conhecidos e, portanto, constituem o alvo de numerosas investigações, seja por facilitarem a compreensão da fisiologia ou por serem promissoras ferramentas para a reprodução assistida. Recentemente, diversos peptídeos ovarianos de ação local têm sido descritos por participarem do controle de todas as fases do desenvolvimento folicular, bem como da modulação de hormônios esteróides ovarianos e gonadotrofinas; entre esses peptídeos estão os fatores de crescimento fibroblástico (FGFs). Os FGFs têm sido extensamente investigados em diversas fases do desenvolvimento folicular e parecem controlar processos como atresia folicular, esteroidogênese, bem como o desenvolvimento folicular pré-antral, sendo a subfamília do FGF7 uma das mais investigadas neste contexto. Assim, esta revisão tem como objetivo sumarizar a participação da subfamília do FGF7 no controle da foliculogênese antral de bovinos.

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The mechanisms that coordinate follicular development are not well known and are, therefore, target of numerous investigations for facilitateing the understanding of physiology or as promising tools for assisted reproduction. Recently, several ovarian peptides with local action have been reported to participate in the control of follicular development in all stages and modulation of gonadotropins andovarian steroid hormones. In this context, fibroblast growth factors (FGFs) have been extensively investigated in different stages of follicular development and seem to control processes such as follicular atresia, steroidogenesis, and pre-antral follicle development, where FGF7 subfamily is one of the most investigated. Therefore, the objective of this review is to summarize the participation of the FGF7 subfamily in the control of bovine antral folliculogenesis.

Asunto(s)

Animales , Bovinos , Folículo Ovárico/embriología , Atresia Folicular , Estradiol , Fase Folicular , Gonadotropinas , Ovario/fisiología

RESUMEN

Os mecanismos que coordenam o desenvolvimento folicular ainda não são completamente conhecidos e, portanto, constituem o alvo de numerosas investigações, seja por facilitarem a compreensão da fisiologia ou por serem promissoras ferramentas para a reprodução assistida. Recentemente, diversos peptídeos ovarianos de ação local têm sido descritos por participarem do controle de todas as fases do desenvolvimento folicular, bem como da modulação de hormônios esteróides ovarianos e gonadotrofinas; entre esses peptídeos estão os fatores de crescimento fibroblástico (FGFs). Os FGFs têm sido extensamente investigados em diversas fases do desenvolvimento folicular e parecem controlar processos como atresia folicular, esteroidogênese, bem como o desenvolvimento folicular pré-antral, sendo a subfamília do FGF7 uma das mais investigadas neste contexto. Assim, esta revisão tem como objetivo sumarizar a participação da subfamília do FGF7 no controle da foliculogênese antral de bovinos. (AU)

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The mechanisms that coordinate follicular development are not well known and are, therefore, target of numerous investigations for facilitateing the understanding of physiology or as promising tools for assisted reproduction. Recently, several ovarian peptides with local action have been reported to participate in the control of follicular development in all stages and modulation of gonadotropins andovarian steroid hormones. In this context, fibroblast growth factors (FGFs) have been extensively investigated in different stages of follicular development and seem to control processes such as follicular atresia, steroidogenesis, and pre-antral follicle development, where FGF7 subfamily is one of the most investigated. Therefore, the objective of this review is to summarize the participation of the FGF7 subfamily in the control of bovine antral folliculogenesis. (AU)

Asunto(s)

Animales , Bovinos , Folículo Ovárico/embriología , Fase Folicular , Estradiol , Ovario/fisiología , Gonadotropinas , Atresia Folicular

RESUMEN

The effects of feed restriction and subsequent refeeding on the gene expression of intestinal enzymes and nutrient transporters at 2 ages, 7 and 35 d, were examined in different groups of broiler chickens. At each age, birds were feed restricted for 7 d (30% of ad libitum intake) followed by 3 d of refeeding ad libitum. Control groups were fed ad libitum. Total RNA of jejunal mucosa was extracted according to the Trizol protocol, and mRNA expression of sodium glucose transporter 1, glucose transporter 2, peptide transporter 1, aminopeptidase, maltase, and sucrase-isomaltase complex was obtained by reverse-transcription PCR. The expression of aminopeptidase, sodium glucose transporter 1, and peptide transporter 1 was higher in feed-restricted groups than in control groups at d 14 (181.4, 116.7, and 80.4%, respectively) and d 42 (143.5, 84.2, and 195.9%, respectively). The mRNA abundance of sucrase-isomaltase complex was higher (159.1%) only in chickens that were feed restricted from d 35 to 42. No statistically significant effect of feed restriction was observed for mRNA abundance of maltase and glucose transporter 2 at either age. After refeeding (d 17 and 45), the RNA abundance of enzymes and nutrient transporters was similar to that in the control group. Thus, this study suggests that an effect of upregulation in gene expression exists during feed restriction that disappears when feed is supplied ad libitum.

Asunto(s)

Pollos/metabolismo , Privación de Alimentos/fisiología , Yeyuno/metabolismo , Proteínas de Transporte de Membrana/metabolismo , ARN Mensajero/metabolismo , Complejo Sacarasa-Isomaltasa/metabolismo , Factores de Edad , Animales , Peso Corporal/fisiología , Mucosa Intestinal/enzimología , Mucosa Intestinal/metabolismo , Yeyuno/enzimología , Masculino , Proteínas de Transporte de Membrana/genética , ARN Mensajero/química , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Complejo Sacarasa-Isomaltasa/genética

RESUMEN

In cattle, most evidence suggests that granulosa cells express LH receptors (LHR) after (or as) the follicle becomes dominant, however there is some suggestion that granulosa cells from smaller pre-dominant follicles may express several LHR mRNA splice variants. The objective of this study was to measure LHR expression in bovine follicles of defined size and steroidogenic ability, and in granulosa cells from small follicles (<6 mm diameter) undergoing differentiation in vitro. Semiquantitative RT-PCR demonstrated that LHR mRNA was undetectable in granulosa cells of follicles <7 mm diameter (nondominant follicles), and increased with follicle diameter in follicles >7 mm diameter. Splice variants with deletions of exon 10 and part of exon 11 were detected as previously described, and we detected a novel splice variant with a deletion of exon 3. Cultured granulosa cells contained LHR mRNA, but with significantly greater amounts of variants with deletions of exon 10 and/or exon 11 compared with cells from dominant follicles. FSH increased the abundance of some but not all LHR mRNA splice variants in cultured granulosa cells. The addition of LH to cultured cells did not increase progesterone secretion, despite the presence of LHR mRNA. Collectively, these data suggest that granulosa cells do not acquire functional LHR until follicle dominance occurs.

Asunto(s)

Empalme Alternativo , Bovinos/genética , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/metabolismo , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Receptores de HL/genética , Animales , Tamaño de la Célula , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Células de la Granulosa/efectos de los fármacos , Folículo Ovárico/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero , Receptores de HL/metabolismo