RESUMO
The alteration of signaling molecules involved in the general metabolism of animals can negatively influence reproduction. In dairy cattle, the development of follicular cysts and the subsequent appearance of ovarian cystic disease (COD) often lead to decreased reproductive efficiency in the herd. The objective of this review is to summarize the contribution of relevant metabolic and nutritional sensors to the development of COD in dairy cows. In particular, we focus on the study of alterations of the insulin signaling pathway, adiponectin, and other sensors and metabolites relevant to ovarian functionality, which may be related to the development of follicular persistence and follicular formation of cysts in dairy cattle. The results of these studies support the hypothesis that systemic factors could alter the local scenario in the follicle, generating an adverse microenvironment for the resumption of ovarian activity and possibly leading to the persistence of follicles and to the development and recurrence of COD.
Assuntos
Doenças dos Bovinos , Cistos Ovarianos , Feminino , Bovinos , Animais , Cistos Ovarianos/veterinária , Cistos Ovarianos/metabolismo , Folículo Ovariano/metabolismo , Reprodução , Insulina/metabolismo , Doenças dos Bovinos/metabolismo , Microambiente TumoralRESUMO
Ovulation is considered an inflammatory, cytokine-mediated event. Cytokines, which are recognized as growth factors with immunoregulatory properties, are involved in many cellular processes at the ovarian level. In this sense, cytokines affect fertility and are involved in the development of different ovarian disorders such as bovine cystic ovarian disease (COD). Because it has been previously demonstrated that ovarian cells represent both sources and targets of cytokines, the aim of this study was to examine the expression of several cytokines, including IL-1ß, IL-1RA, IL-1RI, IL-1RII, IL-4 and IL-8, in ovarian follicular structures from cows with spontaneous COD. The protein expression of these cytokines was evaluated by immunohistochemistry. Additionally, IL-1ß, IL-4 and IL-8 concentrations in follicular fluid (FF) and serum were determined by enzyme-linked immunosorbent assay (ELISA). In granulosa and theca cells, IL-1RI, IL-1RII, IL-1RA and IL-4 expression levels were higher in cystic follicles than in the control dominant follicles. The serum and FF concentrations of IL-1ß and IL-4 showed no differences between groups, whereas IL-8 concentration was detected only in FF of cysts from cows with COD. The FF and serum concentrations of IL-1ß and IL-8 showed no significant differences, whereas IL-4 concentration was higher in FF than in serum in both the control and COD groups. These results evidenced an altered expression of cytokines in ovaries of cows with COD that could contribute to the pathogenesis of this disease.
Assuntos
Líquido Folicular/metabolismo , Interleucinas/metabolismo , Cistos Ovarianos/metabolismo , Cistos Ovarianos/patologia , Animais , Estudos de Casos e Controles , Bovinos , Doenças dos Bovinos , Feminino , Proteína Antagonista do Receptor de Interleucina 1/sangue , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/sangue , Interleucina-4/metabolismo , Interleucina-8/sangue , Interleucina-8/metabolismo , Cistos Ovarianos/veterinária , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Receptores Tipo I de Interleucina-1/metabolismo , Receptores Tipo II de Interleucina-1/metabolismoRESUMO
Cystic ovaries (CO) characterize a disorder frequently found in dairy cattle. However, despite the contributions by several researchers, the mechanism that leads to ovulatory failure has not yet been completely elucidated. Thus, the aim of this study was to examine the mRNA expression of bovine vascular endothelial growth factor (VEGFA)-164, VEGFA-164b and VEGF receptors (VEGFR1 and VEGFR2) by real-time PCR and protein expression by immunohistochemistry, immunofluorescence and Western blot in follicular fluid from dairy cows with spontaneous CO and in an experimental model of follicular persistence induced by prolonged treatment with progesterone. Results showed that both VEGFA isoforms and receptors were coexpressed in granulosa and theca interna cells and in follicular fluid of ovaries from all the groups evaluated. VEGFA-164, VEGFA-164b and VEGFR2 protein expression was higher in theca cells of persistent follicles from group P0 (expected time of ovulation) than in those from dominant follicles (as reference structure) from the control group (pâ¯<â¯0.05). Also, VEGFA-164 expression was higher in theca cells of cysts than in those of dominant follicles of the control group (pâ¯<â¯0.05). In follicular fluid, VEGFA-164 expression was higher in persistent follicles from group P5 (5 days of follicular persistence) than in the control, P0 and P15 groups, and higher in cysts than in dominant follicles from the control group (pâ¯<â¯0.05). This study provides evidence of an altered expression of VEGFA-164, VEGFA-164b and VEGFR2 during the formation of persistent follicles and cysts in cows. Together, these results evidence that early development of CO in cows is concurrent with an altered expression of these growth factors and that these alterations may contribute to the follicular persistence, angiogenic dysregulation and ovulatory failure found in cows with follicular cysts.
Assuntos
Doenças dos Bovinos/genética , Doenças dos Bovinos/fisiopatologia , Cistos Ovarianos/genética , Cistos Ovarianos/fisiopatologia , Folículo Ovariano/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Estudos de Casos e Controles , Bovinos/fisiologia , Doenças dos Bovinos/metabolismo , Feminino , Cisto Folicular/genética , Cisto Folicular/metabolismo , Cisto Folicular/fisiopatologia , Expressão Gênica , Cistos Ovarianos/metabolismo , Ovário/metabolismo , Ovário/patologia , Ovulação/genética , Ovulação/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The lectin histochemical pattern (LHP) was characterized and compared in normal and cystic ovaries of sows. Six biotinylated lectins (PNA, SBA, WGA, RCA-1, DBA and UEA-1) were used on tissue sections. In the normal ovaries, the reaction to UEA-1 and SBA was mild to moderate in mesothelial and endothelial cells. RCA-1 staining was mild to moderate in theca interna of growing follicles, corpora luteum and mesothelium. In addition, this lectin presented strong reaction in endothelial cells, granulosa cells of atretic follicles, zona pellucida of growing follicles and plasma. DBA showed strong intensity in mesothelial and endothelial cells. There was mild to moderate reactivity to WGA in granulosa cells, corpus luteum and theca interna of follicles in development, and moderate in zona pellucida, in granulosa cells of atretic follicles and mesothelium. PNA staining was mild to moderate in oocytes and in the adventitia and media of medullary arteries. Changes in the LHP of the cystic ovaries were noted; however, there were no differences in these findings between the follicular and luteinized cysts. UEA-1 reactivity in the cystic ovaries was moderately reduced in the mesothelial and endothelial cells, whereas there was mild reduction in the DBA staining in the granulosa cells. Reaction to RCA-1 and WGA in the cysts also was decreased in theca interna, zona pellucida and granulosa cells of atretic follicles. Furthermore, endothelium and theca interna in the cystic ovaries presented mild reduction of marcation to SBA, whereas there was decreased reactivity to PNA in the oocytes and adventitia and media layers of the medullary arteries. The results of the current study show that cysts modify the LHP in swine ovaries. These changes of glycoconjugates in many ovarian structures could modify diverse process and may be one of the reasons for decreased fertility in sows.
Assuntos
Lectinas/metabolismo , Cistos Ovarianos/veterinária , Ovário/metabolismo , Doenças dos Suínos/metabolismo , Animais , Células Endoteliais , Feminino , Células da Granulosa , Oócitos , Cistos Ovarianos/metabolismo , Suínos , Zona PelúcidaRESUMO
The objective of this study was to examine the expression of transforming growth factor beta receptor (TGFBR)1, TGFBR2, TGFBR3, activin receptor (ACVR)1B and ACVR2B in ovaries of cows with cystic ovarian disease (COD). The expression of the selected receptors was determined by immunohistochemistry in sections of ovaries from cows with ACTH-induced and spontaneous COD. Expression of TGFBR1 and TGFBR3 was higher in granulosa cells of cysts from cows with spontaneous COD than in tertiary follicles from the control group. Additionally, TGFBR3 expression was higher in granulosa cells of cysts from cows with ACTH-induced COD than in those from the control group and lower in theca cells of spontaneous and ACTH-induced cysts than in tertiary control follicles. There were no changes in the expression of TGFBR2. ACVR1B expression was higher in granulosa cells of tertiary follicles of cows with spontaneous COD than in the control group, whereas ACVR2B expression was higher in cysts of the spontaneous COD group than in tertiary follicles from the control group. The alterations here detected, together with the altered expression of the ligands previously reported, indicate alterations in the response of the ligands in the target cells, modifying their actions at cellular level.
Assuntos
Receptores de Ativinas/metabolismo , Doenças dos Bovinos/metabolismo , Cistos Ovarianos/veterinária , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Hormônio Adrenocorticotrópico/administração & dosagem , Animais , Bovinos , Feminino , Células da Granulosa/metabolismo , Imuno-Histoquímica , Cistos Ovarianos/induzido quimicamente , Cistos Ovarianos/metabolismo , Ovário/metabolismo , Células Tecais/metabolismoRESUMO
Ovarian cystic follicles are the sign of important causes of reproductive failure in numerous species. In this review, some morphological, endocrinological and clinical aspects of cystic follicles in women, cows, mares, sows and bitches are discussed. Follicular cysts are the consequence of the failure of a mature follicle to ovulate at the appointed time of ovulation in the estrous cycle. Although the etiology of follicular cysts remains unknown, this review examines the evidence about the role of endocrine signaling systems in the specific disease or syndrome in each of the species mentioned above. This review also describes, the changes in the pathways of endocrine mechanisms that would trigger disturbances in the intraovarian component underlying the aberrant persistence of follicular cysts. The knowledge of the morphological and endocrinological nature of cystic follicles in different species can provide relevant information to better understand specific diseases when it is integrally analyzed from the comparative medicine viewpoint.
Assuntos
Cisto Folicular/metabolismo , Cistos Ovarianos/metabolismo , Feminino , Cisto Folicular/patologia , Humanos , Cistos Ovarianos/patologiaRESUMO
Cystic ovarian disease (COD) is an important cause of subfertility in dairy cattle. Bone morphogenetic proteins (BMPs), mainly BMP2, BMP4 and BMP6, play a key role in female fertility. In this study, we hypothesized that an altered BMP system is associated with ovarian alterations contributing to COD pathogenesis. Therefore, we examined the expression of BMP2, BMP4 and BMP6 and BMP receptor 1B (BMPR1B) in the ovaries of animals with spontaneous or ACTH-induced COD, as well as during the development of the disease, in a model of follicular persistence induced by low doses of progesterone (at 5, 10 and 15 days of follicular persistence). Results showed changes in BMP2, BMP4 and BMP6 expression during folliculogenesis, in granulosa and theca cells in the COD groups, as well as at different stages of follicular persistence. Results also showed changes in BMPR1B expression in developing follicles in animals with COD, and at the initial stages of follicular persistence (P5). Comparison between groups showed significant differences, mainly in BMP4 and BMP6 expression, in granulosa and theca cells of different follicular categories. The expression of these BMPs also increased in cystic and persistent follicles, in relation to antral follicles of the control group. BMPR1B showed high expression in cystic follicles. Together, these results may indicate an alteration in BMPs, especially in BMP4 and BMP6, as well as in BMPR1B, which occurs early in folliculogenesis and incipiently during the development of COD, which could be a major cause of recurrence of this disease in cattle.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/early/2016/08/01/REP-15-0315/suppl/DC1.
Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 6/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Doenças dos Bovinos/patologia , Cistos Ovarianos/patologia , Folículo Ovariano/patologia , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 6/genética , Receptores de Proteínas Morfogenéticas Ósseas/genética , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/metabolismo , Células Cultivadas , Feminino , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Cistos Ovarianos/genética , Cistos Ovarianos/metabolismo , Folículo Ovariano/metabolismo , Células Tecais/metabolismo , Células Tecais/patologiaRESUMO
Cystic ovarian disease (COD) is an important cause of infertility in dairy cattle. Follicular cell steroidogenesis and proliferation in ovulatory follicles is stimulated by hormones such as insulin and its necessary post-receptor response. The aim of this study was to determine the expression of insulin receptor (IR), IR substrate-1 (IRS1) and phosphatidylinositol 3-kinase (PI3K), key intermediates in the insulin pathway, in control cows and cows with spontaneous COD and ACTH-induced COD. IR and IRS1 mRNA levels were greater in granulosa cells and lower in follicular cysts than in control tertiary follicles. PI3K mRNA levels were similar in all follicles evaluated, whereas the expression of IR, IRS1 and PI3K was similar in theca cells. Protein expression of IR was higher in control tertiary follicles than in the same structures in animals with COD and with cysts. IRS1 and PI3K protein expression showed the same pattern in tertiary and cystic follicles. However, the protein expression of subunit alpha p85 of PI3K was greater in theca cells from tertiary follicles than in cystic follicles. These results provide new insights into the insulin response in cows with COD. The lower gene and protein expressions of some insulin downstream effectors at an early stage of the signaling pathway could negatively influence the functionality of ovaries and contribute to follicle persistence.
Assuntos
Doenças dos Bovinos/metabolismo , Insulina/fisiologia , Cistos Ovarianos/veterinária , Folículo Ovariano/metabolismo , Ácido 3-Hidroxibutírico/sangue , Ácido 3-Hidroxibutírico/metabolismo , Animais , Bovinos , Feminino , Regulação da Expressão Gênica/fisiologia , Insulina/sangue , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Cistos Ovarianos/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Receptor de Insulina/sangue , Receptor de Insulina/metabolismo , Transdução de SinaisRESUMO
The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF-I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF-I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF-II was very similar to pattern noted in IGF-I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF-II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors.
Assuntos
Imuno-Histoquímica/veterinária , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Cistos Ovarianos/veterinária , Folículo Ovariano/metabolismo , Doenças dos Suínos/metabolismo , Animais , Feminino , Regulação da Expressão Gênica/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Cistos Ovarianos/metabolismo , SuínosRESUMO
Follicular growth and steroidogenesis are dependent on gonadotropin binding to their receptors in granulosa and theca cells of ovarian follicles. The aim of the present study was to evaluate the expression patterns of follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHCGR) in ovarian follicular structures from cows with cystic ovarian disease (COD) as compared with those of regularly cycling cows. Relative real-time RT-PCR analysis showed that the expression of FSHR mRNA in granulosa cells was highest in small antral follicles, then decreased significantly as follicles increased in size, and was lowest in cysts. FSHR mRNA was not detected in the theca cells of any follicular category, including cysts. LHCGR mRNA expression in granulosa cells was significantly higher in large antral follicles than in cysts, and not detected in granulosa cells of small and medium antral follicles. In theca cells, the expression level of LHCGR mRNA in medium antral follicles was higher than in small and large antral follicles, whereas that in follicular cysts it was similar to those in small and medium antral follicles, but higher than that in large antral follicles. Our findings provide evidence that there is an altered gonadotropin receptor expression in bovine cystic follicles, and suggest that in conditions characterized by altered ovulation, such as COD, changes in the signaling system of gonadotropins may play a fundamental role in their pathogenesis.
Assuntos
Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/patologia , Cisto Folicular/veterinária , Cistos Ovarianos/veterinária , RNA Mensageiro/metabolismo , Receptores do FSH/metabolismo , Receptores do LH/metabolismo , Análise de Variância , Animais , Bovinos , Primers do DNA/genética , Feminino , Cisto Folicular/metabolismo , Cisto Folicular/patologia , Cistos Ovarianos/metabolismo , Cistos Ovarianos/patologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterináriaRESUMO
Cystic ovarian disease (COD) is one of the main causes of infertility in dairy cattle. It has been shown that intra-ovarian factors may contribute to follicular persistence. Transforming growth factor-beta (TGFB) isoforms are important paracrine and autocrine signalling molecules that regulate ovarian follicle growth and physiology. Considering the importance of these factors in the ovarian physiology, in this study, we examined the expression of TGFB isoforms (TGFB1, TGFB2 and TGFB3) in the ovary of healthy cows and animals with spontaneous and adrenocorticotrophic hormone (ACTH)-induced COD. In the oestrous-synchronized control group, the expression of TGFB1 in granulosa and theca cells was higher in spontaneous cysts than in atretic or tertiary follicles. When we compared TGFB2 expression in granulosa cells from atretic or tertiary follicles from the oestrous-synchronized control group with that in ACTH-induced or spontaneous follicular cysts, we found a higher expression in the latter. The expression of the TGFB isoforms studied was also altered during folliculogenesis in both the spontaneous and ACTH-induced COD groups. As it has been previously shown that TGFB influences steroidogenesis, ovarian follicular proliferation and apoptosis, an alteration in its expression may contribute to the pathogenesis of this disease.
Assuntos
Doenças dos Bovinos/metabolismo , Regulação da Expressão Gênica/fisiologia , Cistos Ovarianos/veterinária , Fator de Crescimento Transformador beta/metabolismo , Hormônio Adrenocorticotrópico/toxicidade , Animais , Bovinos , Feminino , Cistos Ovarianos/induzido quimicamente , Cistos Ovarianos/metabolismo , Ovariectomia/veterinária , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fator de Crescimento Transformador beta/genéticaRESUMO
Cystic ovarian disease (COD) is an important cause of infertility in dairy cattle. Although many researchers have focused their work on the endocrine changes related to this disease, evidence indicates that intraovarian components play an important role in follicular persistence. Activin, inhibin, and follistatin participate as intraovarian regulatory molecules involved in follicular cell proliferation, differentiation, steroidogenesis, oocyte maturation, and corpus luteum function. Given the importance of these factors in folliculogenesis, we examined the expression and immunolocalization of activin/inhibin ßA-subunit, inhibin α-subunit, and follistatin in the ovaries of healthy estrus-synchronized cows and in those of cows with spontaneous or adrenocorticotropic hormone (ACTH)-induced COD. We also studied inhibin B (α ßB) levels in serum and follicular fluid. We found an increased expression of the ßA-subunit of activin A/inhibin A, the α-subunit of inhibin, and follistatin in granulosa cells of spontaneous follicular cysts by immunohistochemistry, and decreased concentrations of inhibin B (α ßB) in the follicular fluid of spontaneous follicular cysts. These results, together with those previously obtained, indicate that the expression of the components of the activin-inhibin-follistatin system is altered. This could lead to multiple alterations in important functions in the ovary like the balance between pro- and anti-apoptotic factors, follicular proliferation/apoptosis, and steroidogenesis, which may contribute to the follicular persistence and endocrine changes found in cattle with COD.
Assuntos
Doenças dos Bovinos/etiologia , Folistatina/fisiologia , Subunidades beta de Inibinas/fisiologia , Inibinas/fisiologia , Cistos Ovarianos/etiologia , Hormônio Adrenocorticotrópico , Animais , Sangue/metabolismo , Estudos de Casos e Controles , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/metabolismo , Feminino , Líquido Folicular/metabolismo , Folistatina/metabolismo , Subunidades beta de Inibinas/metabolismo , Inibinas/metabolismo , Cistos Ovarianos/diagnóstico por imagem , Cistos Ovarianos/metabolismo , Cistos Ovarianos/veterinária , Subunidades Proteicas , UltrassonografiaRESUMO
Cystic ovarian disease (COD), which is considered one of the most important causes of reproductive failure in dairy cattle, induces intraovarian changes in the expression of numerous genes. The purpose of this study was to analyze the changes in the expression of Heat Shock Proteins (HSPs) in ovaries from bovines with cystic ovarian disease induced by ACTH. Immunoreactivity for Heat Shock Proteins (HSPs) in ovaries of cows with induced COD showed differential expression patterns in growing follicles from the control group. The immunopositive area for Hsp27 and Hsp60 in granulosa cells showed significant differences between tertiary follicles from normal cycling animals and those from animals with induced COD. The cysts showed increased Hsp27 immunostaining in theca cells in relation to tertiary follicles from normal cycling cows. Hsp70 immunostaining was more intense in cystic follicles than in other follicular categories from animals with induced COD, in both granulosa and theca cells. In granulosa cells, tertiary follicles from the control group showed higher levels of Hsp90 than cysts. These results demonstrate that there are differences in HSP protein expression when COD is induced. In fact, HSP expression would be part of the functional response to the changes in hormones and neurotransmitters induced by stress, indicating that HSPs can control hormonal functions and vice versa.
Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Doenças dos Bovinos/metabolismo , Proteínas de Choque Térmico/biossíntese , Cistos Ovarianos/veterinária , Ovário/metabolismo , Animais , Bovinos , Doenças dos Bovinos/induzido quimicamente , Chaperonina 60/biossíntese , Chaperonina 60/fisiologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Proteínas de Choque Térmico HSP27/biossíntese , Proteínas de Choque Térmico HSP27/fisiologia , Proteínas de Choque Térmico/fisiologia , Cistos Ovarianos/induzido quimicamente , Cistos Ovarianos/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Ovário/efeitos dos fármacos , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismoRESUMO
Cystic ovarian disease (COD) is one of the main factors responsible for reproductive disorders in cattle. Although the pathogenesis and mechanism of cyst formation are not fully understood, it has been proposed that the IGF system could play an essential role, as it is a key intraovarian regulator. The aim of the present study was to determine whether the altered levels in IGF1 detected in bovines with COD are associated with changes at mRNA level or with differential modulation by IGFBPs. The mRNA levels of the IGF components studied were analyzed by real time PCR and in situ hybridization, and IGFBP expression and activity were assayed by immunohistochemistry and ligand blot, respectively. Results showed a decreased IGF1 mRNA level due to a lower granulosa cell gene expression in cystic follicles (P<0.05). Results also showed variations in IGFBP expression in the intraovarian cellular compartment and concentration in follicular fluid, and suggest that IGFBP3 is a key regulator of intrafollicular IGF1 in animals with COD.
Assuntos
Bovinos/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Cistos Ovarianos/veterinária , Animais , Western Blotting/veterinária , Feminino , Líquido Folicular/metabolismo , Imuno-Histoquímica/veterinária , Hibridização In Situ/veterinária , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Cistos Ovarianos/metabolismo , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/veterináriaRESUMO
Numerous experimental models in different species have been developed for the study of polycystic ovarian syndrome. In this study, we used a model of induction of polycystic ovaries (PO) in rats by exposure to constant light to study the distribution and variations of glycosylated residues present in the different ovarian structures. Seven biotinylated lectins were used (Con-A, WGA, DBA, SBA, PNA, RCA and UEA-I) on tissue sections, and detection was performed using the streptavidin/peroxidase method. In tissue sections was observed an increase in affinity for Con-A in the granulosa and theca interna of growing follicles and cysts in animals with PO in relation to the control group. Follicular cysts showed higher affinity for WGA and RCA-I which growing follicles in the same group, and there was a decrease in affinity for PNA in the cysts in relation to the growth of follicles in both groups. Atretic follicles in both groups showed greater labelling with lectins PNA, SBA and RCA-I in relation to healthy follicles. It could also be noted that the zona pellucida of cystic follicles lost the affinity for the lectin Con-A. There was no staining on follicles in any category with the lectins DBA and UEA-I, although it was staining in the corpus luteum (control group) and in the mesothelium and interstitial glands of both groups with DBA. These observations probably reflect changes in the glycosaminoglycans present in the different ovarian compartments or in the glycosylation of cellular components essential for proper follicular dynamics.
Assuntos
Lectinas/metabolismo , Luz/efeitos adversos , Cistos Ovarianos/etiologia , Animais , Feminino , Regulação da Expressão Gênica , Cistos Ovarianos/metabolismo , Ligação Proteica/fisiologia , RatosRESUMO
Cystic ovarian disease (COD) is an important cause of infertility in cattle. The altered follicular dynamics and cellular differentiation observed in COD may be mediated through a disruption of the expression of steroid receptors and their associated transcriptional cofactors. The aim of this study was to determine the protein expression profiles of ESR1, ESR2, PGR, AR, NCOA3, NCOR2, and PHB2 (REA) in ovarian follicles in an experimental model of COD induced by the administration of ACTH. Ovaries were collected and follicles were dissected from heifers during the follicular phase (control) or from heifers treated with ACTH to induce the formation of ovarian follicular cysts. Ovaries were fixed, sectioned, and stained immunohistochemically for steroid receptors and the associated transcription factors. The relative expression of ESR1 was similar in follicular cysts and in tertiary follicles from both control and cystic cows and was significantly higher than in secondary follicles. The expression of ESR2 in the granulosa was higher in cystic follicles. No differences were seen for PGR. The expression of androgen receptor was significantly increased in tertiary follicles with lower immunostaining in cysts. The expression of NCOA3 was observed in the granulosa and theca with a significantly increased expression in the theca interna of cystic follicles. The highest levels of NCOR2 expression in granulosa, theca interna, and theca externa were observed in cysts. In granulosa cells, NCOR2 levels increase progressively as follicles mature and the treatment had no effect. In summary, ovaries from animals with induced COD exhibited altered steroid receptor expression compared with normal animals, as well as changes in the expression of their regulators. It is reasonable to suggest that in conditions characterized by altered ovulation and follicular persistence, such as COD, changes in the intra-ovarian expression of these proteins could play a role in their pathogenesis.
Assuntos
Doenças dos Bovinos/metabolismo , Correpressor 2 de Receptor Nuclear/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Cistos Ovarianos/metabolismo , Receptores de Esteroides/metabolismo , Proteínas Repressoras/metabolismo , Animais , Especificidade de Anticorpos , Bovinos , Feminino , Imuno-Histoquímica , Ovário/metabolismo , ProibitinasRESUMO
As aging proceeds, fertility problems arise, and the success rate of in vitro fertilization declines. During reproductive aging, rat ovaries present spontaneous formation of cysts, followed by a concomitant increase in sympathetic nerve activity, causing infertility and cessation of ovarian function. ß2-Adrenergic receptors, which are activated by noradrenaline (NA), modify follicular development and steroid secretions; thus, increased nerve activity has been associated with the development and maintenance of cystic structures. The purpose of this work was to block the effect of this sympathetic activity through in vivo administration of propranolol (a ß-adrenergic receptor antagonist) to determine whether it delays cyst formation and cessation of the ovarian function in rats that had reached the subfertile period. Propranolol was administrated daily to 8- and 10-month-old rats for 2 months. Estrous cycling activity was monitored by vaginal smear, serum concentration of the steroidal hormones was determined by enzyme-immune assay and morphological analysis of the ovaries was performed using 6 µm tissue slices stained with hematoxylin-eosin. Propranolol increased the number of healthy follicles, the ovulation rate, and levels of serum sexual steroids (androstenedione, testosterone, and estradiol) and recovered estrous cycling activity. It also decreased the number of follicular cysts. These results suggest that the blockade of ß-adrenergic receptors recovered ovarian function during reproductive aging. It is suggested that propranolol induces a time-dependent extension of the subfertile window, and it could be used to increase the success rate of fertility programs in aging woman.
Assuntos
Antagonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Período Fértil/efeitos dos fármacos , Cistos Ovarianos/tratamento farmacológico , Propranolol/administração & dosagem , Animais , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Ciclo Menstrual/efeitos dos fármacos , Cistos Ovarianos/genética , Cistos Ovarianos/metabolismo , Cistos Ovarianos/fisiopatologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiopatologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2/genética , Receptores Adrenérgicos beta 2/metabolismoRESUMO
Steroid receptors have been demonstrated to be important intra-ovarian regulators of follicular development and ovulatory processes. The aim of the present study was to determine the expression of steroid receptor mRNA in ovarian follicular structures from cows with cystic ovarian disease (COD) compared with ovarian structures from regularly cycling cows using reverse transcription polymerase chain reaction (RT-PCR). The cystic follicles showed a higher estrogen receptor α (ESR1) mRNA expression in the theca and granulosa and a lower estrogen receptor ß (ESR2) expression. The cystic follicles also showed a strong expression of androgen receptor mRNA in the granulosa. No changes were observed in total progesterone receptor mRNA, but a very significant increase in the B isoform was found in the granulosa of the cystic follicles. The findings of the current study provide evidence that an altered steroid signaling system may be present in bovine follicular cysts, and we suggest that in conditions characterized by altered ovulation, such as COD, changes in the expression of ovarian steroid receptors could play a fundamental role in the pathogeny of this disease.
Assuntos
Doenças dos Bovinos/metabolismo , Cistos Ovarianos/veterinária , Folículo Ovariano/metabolismo , RNA Mensageiro/metabolismo , Receptores de Esteroides/metabolismo , Animais , Bovinos , Doenças dos Bovinos/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Cistos Ovarianos/metabolismo , RNA Mensageiro/genética , Receptores de Esteroides/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
In the study, the gene expression of several heat shock proteins (HSPs) was determined in normal follicles and cystic follicles from cattle. A lower expression of HSP10 and HSP40 was observed in granulosa and theca cells of cysts compared to normal follicles. HSP27 was significantly less expressed in granulosa cells in cystic and large antral follicles than in other follicular categories. HSP60 and HSP90a expressions were highest in theca cells of cysts. However, HSP70 and HSP90b exhibited a lower expression in cysts than in healthy follicles.
Assuntos
Proteínas de Choque Térmico/metabolismo , Cistos Ovarianos/metabolismo , Folículo Ovariano/metabolismo , Animais , Bovinos , Feminino , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Ovarian cysts are one of the major causes of infertility in dairy cows. The development is associated with an endocrine imbalance in the hypothalamo-hypophyseal-gonadal axis in which endocrine factors participate in follicular growth and differentiation and in the secretion of ovarian hormones. Insulin-like growth factor family are essential local regulators of ovarian follicle development and functionality and actions are mediated by binding protein activity. The aim of the present study was to analyze the expression of IGFBP-2 and IGFBP-3 in developing follicles of normal estrous cycling animals and with spontaneous and induced cystic ovarian disease (COD) to determine IGF bioavailability. The mRNA of IGFBP-2 and IGFBP-3 in follicular walls was quantified by reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Protein expression was analyzed by immunohistochemistry. The results demonstrated reduced amounts of mRNA of both IGFBPs in the granulosa cells of ovarian follicles of animals with COD (P<0.05). The present study suggests that the IGF system or imbalances between IGFs and IGFBPs may be involved in COD of cattle.