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1.
Theriogenology ; 195: 168-175, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36335720

RESUMO

The cytokines of the interleukin-1 (IL-1) family are closely involved in the resolution of inflammation in cows with metritis and endometritis. However, little is known about the role of these cytokines beyond uterine regression in the absence of disease, especially around conception. Thus, the aim of this study was to examine the gene and protein expression of IL-1α, IL-1ß, IL-1RI, IL-1RII and IL-1Ra in endometrial biopsies previous to conception, to evaluate the possible association of these cytokines with delayed conception in dairy cows. Gene and protein expression levels were evaluated by real-time PCR and immunohistochemistry, respectively. The gene expression levels of cytokines were not associated with the duration of the period to conception following parturition. However, high protein expression of IL-1ß and low protein expression of IL-1Ra were significantly associated with early conception. These results suggest that an imbalanced protein expression of IL-1ß and IL-1Ra in the endometrium of dairy cows could be part of the maternal immune response mechanism necessary to propitiate early conception and probably to maintain pregnancy.


Assuntos
Doenças dos Bovinos , Endometrite , Feminino , Gravidez , Bovinos , Animais , Proteína Antagonista do Receptor de Interleucina 1/genética , Endométrio , Fertilização , Endometrite/genética , Endometrite/veterinária , Biópsia/veterinária , Doenças dos Bovinos/genética
2.
Anim Reprod Sci ; 232: 106818, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343817

RESUMO

The nutritional conditions and immune status of dairy cows affect reproductive performance. This study was conducted with the aim to analyze the phagocytic activity (PA) and phagocytic capacity (PC) of circulating monocytes after the period of transition from pregnancy to lactation, to evaluate possible associations with duration of time period to conception following parturition. Results indicated PA was not associated with duration of time period to conception following parturition. In contrast, cows with a lesser PC conceived earlier (98 ± 9 days in milk, DIM) than those with a greater PC (168 ± 15 DIM). Based on these results, to analyze the association of the hormonal and metabolic milieu with the PA and PC, the animals were grouped considering the days to conception following parturition. In the group with the greater number of days to conception (>168 DIM), the PA was associated with concentrations of progesterone and beta-hydroxybutyrate (BHB) at 90 DIM and glucose at 120 DIM, whereas PC was associated with the concentrations of progesterone, cortisol and glucose at 90 DIM, non-esterified fatty acids (NEFA) at 120 DIM, 17ß-estradiol at 150 DIM, and 17ß-estradiol and BHB at 180 DIM. Overall, these results represent a new perspective related to the reproductive performance of dairy cows. The modifications of cellular functions may be useful for predicting the onset of health complications in dairy cows and to manage cows in ways that result in an enhanced fertility during the subsequent lactational period.


Assuntos
Bovinos/fisiologia , Fertilização/fisiologia , Monócitos/fisiologia , Fagocitose/fisiologia , Animais , Feminino , Lactação/fisiologia , Parto , Gravidez
3.
Theriogenology ; 138: 52-65, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31301448

RESUMO

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 (p < 0.05). Also, VEGFA-164 expression was higher in theca cells of cysts than in those of dominant follicles of the control group (p < 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 (p < 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/metabolismo
4.
Theriogenology ; 110: 61-73, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29334661

RESUMO

Cystic ovarian disease (COD) is an important cause of infertility in dairy cattle. The main signs of this infertility are ovulation failure and follicular persistence. The aim of this study was to examine the expression of the cytokines IL-1ß, IL-1RI, IL-1RII, IL-1RA and IL-4 in ovarian follicular structures at different times of persistence in a model of follicular persistence induced by prolonged administration of progesterone in dairy cows. Protein expression of IL-1ß, IL-1RI, IL-1RII, IL-1RA and IL-4 was evaluated by immunohistochemistry. Additionally, IL-1ß and IL-4 concentrations in follicular fluid and serum were determined by ELISA. In granulosa cells, IL1-RII and IL-4 expression was higher in follicles with different persistence times than in the control dominant follicles. IL-1RA expression was higher in persistent follicles of the P15 group (15 days of follicular persistence) than in those of the control group. In theca cells, IL-1RII expression was higher in persistent follicles of the P0 group (expected time of ovulation) than in dominant follicles from the control group (p < .05) and the other persistence groups, whereas IL-4 expression was higher in persistent follicles of groups P0 and P15 than in the dominant follicles of the control group (p < .05). Differences between serum and follicular fluid within each group were detected only in P0 for IL-1ß, and in the control, P10 and P15 groups for IL-4 (p < .05). These results complement previous results, evidencing that early development of COD in cows is concurrent with an altered expression of cytokines in different ovarian follicular structures and may contribute to the follicular persistence and ovulation failure found in cattle with follicular cysts.


Assuntos
Anovulação/metabolismo , Bovinos/fisiologia , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/metabolismo , Folículo Ovariano/fisiologia , Receptores Tipo II de Interleucina-1/metabolismo , Receptores Tipo I de Interleucina-1/metabolismo , Animais , Anovulação/veterinária , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/fisiopatologia , Sobrevivência Celular , Indústria de Laticínios , Feminino
5.
J Comp Pathol ; 156(2-3): 191-201, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27993358

RESUMO

The most important regulators of tissue remodelling during ovarian follicular growth, development, ovulation and atresia are gonadotropins, steroid hormones, growth factors and different proteolytic enzymes. Matrix metalloproteinases (MMPs) such as collagenase or gelatinase (i.e. MMP-1, -8, -2 and -9) and associated tissue inhibitors of metalloproteinases (TIMP-1, -2, -3 and -4) control connective tissue remodelling during follicular rupture. In this study, we hypothesized that an imbalance in the MMP-TIMP system may be an intra-ovarian component that contributes to the pathogenesis of cystic ovarian disease (COD) in cows. Taking into account that the control of MMP activity by TIMPs could determine their effects in both physiological and pathological conditions, MMP and TIMP mRNA and protein expression was examined by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC), respectively, in ovaries from control cows and cows with COD. Expression of mRNA encoding MMP-2, TIMP-1 and TIMP-2 was lower in follicular cysts than in control pre-ovulatory follicles, while the results by IHC showed this imbalance only for TIMP-2 protein expression. Additional analysis by zymography to evaluate the gelatinase activity of MMP-2 and MMP-9 demonstrated higher MMP-2 activity in follicular fluid (FF) of cysts than in FF of pre-ovulatory follicles. On the other hand, MMP-9 activity was increased in follicular cysts and absent in the FF of pre-ovulatory follicles. These findings suggest that the altered mRNA expression and activities of the MMP-TIMP system may be related to the failure in ovulation and follicular development observed in COD.


Assuntos
Doenças dos Bovinos/enzimologia , Metaloproteinases da Matriz/metabolismo , Cistos Ovarianos/veterinária , Inibidores Teciduais de Metaloproteinases/metabolismo , Animais , Western Blotting , Bovinos , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Reação em Cadeia da Polimerase em Tempo Real
6.
J Comp Pathol ; 153(2-3): 116-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26065705

RESUMO

A growing body of evidence suggests that ovulation shares many of the features of an inflammatory reaction and that cytokines play many diverse and important roles in reproductive biology. The aim of this study was to examine the expression of the pro-inflammatory cytokines interleukin (IL)-1α, IL-6 and tumour necrosis factor (TNF)-α in ovarian cells from cows with cystic ovarian disease (COD) as compared with that in ovarian structures from regularly cycling cows. Expression of genes encoding IL-1α, IL-6 and TNF-α was detected by real-time polymerase chain reaction in follicular cells from ovaries from healthy cows and cows with COD with no significant differences. However, immunohistochemistry showed increased expression of IL-1α, IL-6 and TNF-α in cystic follicles, suggesting that this expression may be related to the persistence of follicular cysts. The effect of COD was evident for IL-1α and TNF-α, and a follicular structure-disease interaction was observed in the expression of all the cytokines evaluated. Thus, altered expression of these proinflammatory cytokines may be related to ovulation failure and development of follicular cysts.


Assuntos
Doenças dos Bovinos/patologia , Citocinas/biossíntese , Cistos Ovarianos/veterinária , Folículo Ovariano/patologia , Animais , Western Blotting , Bovinos , Doenças dos Bovinos/imunologia , Citocinas/análise , Feminino , Imuno-Histoquímica , Cistos Ovarianos/imunologia , Cistos Ovarianos/patologia , Folículo Ovariano/imunologia , Reação em Cadeia da Polimerase em Tempo Real
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