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1.
Sheng Li Xue Bao ; 72(1): 63-74, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32099984

RESUMO

Ovary, the female gonad in mammals, is a heterogeneous organ consisting of oocytes and various types of somatic cells. The functions of ovary is not only governing the health of individual female by regulating endocrine status, but also determining the production of mature oocytes which allow the continuation of species. As the fundamental unit of female reproduction, ovarian follicle consists of germline oocyte and follicle somatic cells, and the folliculogenesis is an accurate and orderly process of internal coordination and external regulation in mammals. The gonadotropin-dependent stage of follicle development, from early antral follicle to ovulation, directly regulates the reproductive cycles of the female, has been extensively investigated. Recently, increased lines of evidence show that the fine tuned early folliculogenesis plays a pivotal role in the maintenance of female reproductive lifespan. Further exploration of the mechanism of follicular development could lead to a more comprehensive understanding about how females maintain their proper reproductive lifespan in mammals, which may provide the possibility to design new therapeutic approaches against female reproductive ageing in future. With the advances of technologies and methods, especially the widespread application of genetically modified animals and novel microscopic technology, the research on regulating mechanisms of in vivo follicular development, especially the early stage development of follicles, has made great progress. In this review, we summarized the regulating mechanisms of in vivo folliculogenesis around the key developmental events under physiological conditions, with a focus on the research progress of the early development of follicles in recent years.


Assuntos
Oogênese , Folículo Ovariano/fisiologia , Animais , Feminino , Mamíferos , Oócitos
2.
Theriogenology ; 142: 276-283, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31708195

RESUMO

The peroxisome proliferator-activated receptor gamma (PPARG, also called NR1C3) is a nuclear receptor of the peroxisome proliferator-activated receptor family (PPAR). PPARs are involved in the regulation of apoptosis, cell cycle, estradiol and progesterone synthesis, and metabolism. However, the role of PPARs and their regulation during follicular development and ovulation in monovular species remain poorly understood. In this study, a well-established intrafollicular injection model was used to investigate if the PPARG participates in the regulation of dominant follicle development and ovulation in cattle. Findings from this study revealed that the relative mRNA abundance of PPARG was similar between dominant and subordinate follicles around follicle deviation, decreased after the LH surge, and increased before ovulation. In addition, a quadratic correlation was found between PPARG mRNA levels in granulosa cells and progesterone concentration in the follicular fluid. Intrafollicular injection of 50 µM Troglitazone (TGZ; a PPARG agonist) inhibited follicular growth and decreased CYP19A1 mRNA abundance in granulosa cells. These findings indicate that PPARG is involved in the regulation of steroidogenesis, follicle growth and ovulation in cattle.


Assuntos
Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , PPAR gama/agonistas , Troglitazona/farmacologia , Animais , Bovinos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/fisiologia , Oogênese/efeitos dos fármacos , Oogênese/genética , Ovulação/efeitos dos fármacos , Ovulação/genética , PPAR gama/genética , PPAR gama/metabolismo
3.
Theriogenology ; 142: 284-290, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31711701

RESUMO

The aims of this study were to investigate the effects of epidermal growth factor (EGF) and progesterone on the development, viability and the gene expression of bovine secondary follicle culture in vitro for 18 days. Secondary follicles (∼0.2 mm) were isolated from ovarian cortex and individually cultured at 38.5 °C, with 5% CO2 in air, for 18 days, in TCM-199+ (n = 63) alone (control medium) or supplemented with 10 ng/mL progesterone (n = 64), 10 ng/mL EGF (n = 61) or both EGF and progesterone (n = 66). The effects of these treatments on growth, antrum formation, viability, ultrastructure and mRNA levels for GDF-9, c-MOS, H1foo and cyclin B1 were evaluated, significantly different (p < 0.05). The results showed that there was a progressive increase in follicular diameter in all treatments, but only follicles cultured in medium supplemented with EGF had increased significantly in diameter when compared to follicles cultured in the control medium at the end of the culture period, significantly different (p < 0.05). A positive interaction between EGF and progesterone was not observed. In addition, the presence of EGF, progesterone or both in culture medium did not influence the rate of follicle survival and antrum formation. However, the presence of only progesterone in cultured medium increased the expression of mRNAs for GDF9 and cyclin B1 in oocytes. EGF also significantly increased the levels of mRNAs for cMOS and GDF9 when compared to follicles cultured in control medium. Ultrastructural analyzes showed that cultured follicles in all treatments maintained the integrity of granulosa cells. In conclusion, the EGF promotes the development of secondary follicles cultured in vitro for 18 days and increases the expression of cMOS and GDF9, while progesterone alone or in association with EGF have not a positive effect on follicular growth. However, progesterone increases the expression of GDF9 and cyclin B1 in oocytes.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Expressão Gênica/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Progesterona/farmacologia , Animais , Bovinos , Células Cultivadas , Feminino , Genes mos/efeitos dos fármacos , Genes mos/genética , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/fisiologia , Fator 9 de Diferenciação de Crescimento/genética , Folículo Ovariano/fisiologia
4.
Reprod Biol Endocrinol ; 17(1): 106, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805966

RESUMO

BACKGROUND: To evaluate the impact of follicle-flushing during oocyte collection on embryo development potential retrospectively. METHODS: A total of 1714 cases, including 133 who experienced retrieval difficulty (repeated follicle-flushing) on the day of oocyte retrieval (difficulty group) and the control 1581 cases (control group), were assessed in this retrospective study. The number of oocytes recovered, two pro-nuclei fertilization (2PN-fertilization), day 3 good-quality embryo and day 5/6 blastocyst utilization rates were compared between the difficulty group and control group correspondingly. Embryo implantation, clinical pregnancy and neonatal outcomes were further analyzed between the two groups in the fresh day- 3 embryo transfer cycles. RESULTS: The number of oocytes recovered in the difficulty group (9.08 ± 4.65) were significantly reduced compared with the control group (12.13 ± 5.27),P < 0.001; The 2PN-fertilization, day 3 good-quality embryo and blastocyst utilization rates were significantly lower in the difficulty group compared with controls (71.7% vs. 75.7%; 52.7% vs. 56.5%; 31.9% vs. 37.0%, all P < 0.05). Embryo implantation in the difficulty group was 53.2%, which was lower than the control value of 58.7%, although not reaching statistical significance. The rate of fresh embryo transfer cycles in the difficulty group was lower than normal ones (51.88% vs. 61.99%, P = 0.026). The pregnancy and live birth rates were similar between the two groups. But the rate of spontaneous miscarriages of the difficulty group was higher than the control group, although not reaching statistical significance. The neonatal outcomes had no statistical difference between the two groups. CONCLUSIONS: Oocyte retrieval difficulty, which include repeated flushing and the corresponded extending time required for oocyte recovery, significantly reduced day 3 good-quality embryo and blastocyst utilization rates of these patients. But the live birth rate had no difference between the difficulty group and the normal ones.


Assuntos
Desenvolvimento Embrionário , Fertilização In Vitro/métodos , Recuperação de Oócitos/métodos , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Aborto Espontâneo , Adulto , Transferência Embrionária/métodos , Feminino , Humanos , Nascimento Vivo , Oócitos/citologia , Folículo Ovariano/citologia , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
5.
Reproduction ; 158(6): F113-F126, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31846436

RESUMO

The ovarian follicle and its maturation captivated my imagination and inspired my scientific journey - what we know now about this remarkable structure is captured in this invited review. In the past decade, our knowledge of the ovarian follicle expanded dramatically as cross-disciplinary collaborations brought new perspectives to bear, ultimately leading to the development of extragonadal follicles as model systems with significant clinical implications. Follicle maturation in vitro in an 'artificial' ovary became possible by learning what the follicle is fundamentally and autonomously capable of - which turns out to be quite a lot. Progress in understanding and harnessing follicle biology has been aided by engineers and materials scientists who created hardware that enables tissue function for extended periods of time. The EVATAR system supports extracorporeal ovarian function in an engineered environment that mimics the endocrine environment of the reproductive tract. Finally, applying the tools of inorganic chemistry, we discovered that oocytes require zinc to mature over time - a truly new aspect of follicle biology with no antecedent other than the presence of zinc in sperm. Drawing on the tools and ideas from the fields of bioengineering, materials science and chemistry unlocked follicle biology in ways that we could not have known or even predicted. Similarly, how today's basic science discoveries regarding ovarian follicle maturation are translated to improve the experience of tomorrow's patients is yet to be determined.


Assuntos
Bioengenharia , Preservação da Fertilidade , Infertilidade Feminina/prevenção & controle , Oócitos/fisiologia , Oogênese , Folículo Ovariano/fisiologia , Criopreservação , Feminino , Humanos , Oócitos/citologia , Folículo Ovariano/citologia
6.
Results Probl Cell Differ ; 68: 455-475, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598867

RESUMO

Nutritional modes operating during embryonic/larval development of viviparous species range from "pure" lecitothrophy in which embryos rely solely on reserve materials (yolk spheres, lipid droplets, and glycogen particles) accumulated in the egg cytoplasm to matrotrophy in which embryos are continuously supplied with nutrients from a parental organism. Interestingly, a wide spectrum of diverse "mixed" modes employed in the embryo nourishment have also been described among viviparous species. Here, we summarize results of histochemical, ultrastructural, and biochemical analyses of reproductive systems as well as developing embryos of two closely related viviparous species of earwigs (Dermaptera), Hemimerus talpoides and Arixenia esau. These analyses clearly indicate that morphological as well as physiological modifications (adaptations) supporting viviparity and matrotrophy in Hemimerus and Arixenia, with the exception of a complex biphasic respiration, are markedly different. Most importantly, Hemimerus embryos complete their development inside terminal (largest) ovarian follicles, whereas Arixenia embryos, after initial developmental stages, are transferred to highly modified lateral oviducts, that is the uterus, where they develop until the release (birth) of larvae. The obtained results strongly suggest that viviparity in hemimerids and arixeniids had evolved independently and might therefore serve as an example of evolutionary parallelism as well as remarkable functional plasticity of insect reproduction and embryonic development.


Assuntos
Evolução Biológica , Desenvolvimento Embrionário , Neópteros/embriologia , Neópteros/fisiologia , Folículo Ovariano/fisiologia , Oviductos/fisiologia , Reprodução/fisiologia , Viviparidade não Mamífera/fisiologia , Animais , Feminino , Larva , Neópteros/anatomia & histologia
7.
Exp Parasitol ; 207: 107778, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629698

RESUMO

The murine infection with Taenia crassiceps WFU (T. crassiceps WFU) cysticerci has been widely used as an experimental model to better understand human cysticercosis. Several reports have established that the host hormonal environment determines the susceptibility and severity of many parasite infections. Female mice are more susceptible to infection with T. crassiceps cysticerci suggesting that a rich estrogen environment facilitates their reproduction. Ovarian androgens and estrogens are synthesized by key enzymes as P450-aromatase and 17α-hydroxilase/17, 20 lyase (P450C17). The aim of this study was to determine the effect of chronic intraperitoneal infection of T. crassiceps WFU cysticerci on mice ovarian follicular development, ovulation, the expression of ovarian P450-aromatase and P450C17, and serum 17ß-estradiol, key enzymes of the ovarian steroidogenic pathway. To perform this study ovaries and serum were obtained at two, four and six months from T. crassiceps WFU cysticerci infected mice, and compared to those of healthy animals. The ovaries were fixed and processed for histology or lysed in RIPA buffer for Western blot using specific antibodies for P450C17 and P450-aromatase. 17ß-estradiol serum concentration was measured by ELISA. The results showed that the infection with T. crassiceps WFU cysticerci significantly reduced the number of primordial and primary follicles after two months of infection. Through the course of the study, the corpus luteum number began to decrease, whereas atretic follicles increased. The expression of ovarian P450C17 and P450-aromatase as well as serum E2 concentration were significantly increased in the infected group compared to control. These findings show that chronic infection with Taenia crassiceps WFU may alter the reproductive functions of the female mice host.


Assuntos
Estradiol/sangue , Folículo Ovariano/fisiologia , Ovário/enzimologia , Teníase/fisiopatologia , Análise de Variância , Animais , Western Blotting , Peso Corporal , Corpo Lúteo/patologia , Densitometria , Ensaio de Imunoadsorção Enzimática , Tubas Uterinas/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Ovário/anatomia & histologia , Distribuição Aleatória , Esteroide 17-alfa-Hidroxilase/metabolismo , Teníase/sangue , Teníase/enzimologia , Útero/anatomia & histologia
8.
J Assist Reprod Genet ; 36(11): 2379-2384, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31625035

RESUMO

OBJECTIVE: To evaluate the hormonal profile, antral follicle count (AFC) and ovarian response of patients with hypogonadotropic hypogonadism (HH). DESIGN: Observational retrospective cohort including infertile women with HH undergoing assisted reproductive treatment (ART). SETTING: University-affiliated infertility center. PATIENT(S): Thirty-three women with HH who underwent ART between January 2007 and September 2018. The control group comprised 66 age-matched counterparts with tubal or male factor infertility. The patients with an abnormal karyotype, and those presenting primary or secondary amenorrhea due to other causes, were cautiously excluded. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The primary outcome was serum levels of anti-Müllerian hormone (AMH) and AFC. We also investigated whether HH impacts ovarian response and reproductive outcomes. RESULT(S): Although AFC was similar between groups, HH patients showed significantly higher AMH levels (4.6 ± 2.7 ng/mL vs. 3.0 ± 1.9, p = 0.010) and lower basal FSH and LH. While the HH group needed longer stimulation [13 days (11-26) vs. 10 (7-14), p < 0.001] and higher gonadotropin doses [2700 IU (825-6300) vs. 2100 (425-5000), p = 0.038 ], no significant differences were detected in either the number or maturity of retrieved oocytes, or in the fertilization rate, number of embryos transferred, implantation rate, clinical pregnancy rate and live birth rate per cycle. CONCLUSION(S): HH patients present higher AMH levels, but similar AFC. Despite requiring longer stimulation and higher gonadotropin doses, ovarian response and reproductive outcomes seem unaffected.


Assuntos
Gonadotropinas/metabolismo , Hipogonadismo/metabolismo , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Reserva Ovariana/fisiologia , Hormônio Antimülleriano/metabolismo , Coeficiente de Natalidade , Feminino , Fertilização In Vitro/métodos , Humanos , Recuperação de Oócitos/métodos , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
9.
Cryobiology ; 91: 77-83, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31639331

RESUMO

This study aimed to evaluate different vitrification methods using distinct cryoprotectants (CPAs) for the preservation of collared peccary ovarian preantral follicles (PFs). Ovarian pairs from six females were fragmented and three fragments (fresh control group) were immediately evaluated for morphology, viability, cell proliferation capacity (assessed by quantifying the number of argyrophilic nucleolus organizer regions - NORs), and apoptosis (by the identification of activated caspase-3 expression). The remaining 18 fragments were vitrified using the solid surface vitrification (SSV) method or the ovarian tissue cryosystem (OTC) with 3 M ethylene glycol (EG), 3 M dimethylsulfoxide (DMSO), or a combination of the two (1.5 M EG/1.5 M DMSO). After two weeks, samples were rewarmed and evaluated as described previously. The OTC with any of the CPAs provided a similar conservation of morphologically normal PFs as the fresh control group (75.6 ±â€¯8.6%); however, the SSV was only efficient with DMSO alone (63.9 ±â€¯7.6%). Regarding the viability or cell proliferation, all tested groups provided post rewarming values similar to those observed for the fresh control group, 84.0 ±â€¯2.9% viable cells with 2.0 ±â€¯0.2 NORs. Related to apoptosis analysis, only the OTC with EG (46.7%) and the SSV method with EG (43.4%) or the combination of EG and DMSO (33.4%) provided similar values to those found for the fresh control group (36.7%). Our findings indicate the utilization of a closed system, the OTC, with 3 M EG as the CPA for the vitrification of collared peccary ovarian tissue.


Assuntos
Artiodáctilos/fisiologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Folículo Ovariano/fisiologia , Animais , Apoptose/efeitos dos fármacos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Criopreservação/métodos , Feminino , Folículo Ovariano/citologia , Vitrificação
10.
Schweiz Arch Tierheilkd ; 161(10): 627-638, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31586925

RESUMO

INTRODUCTION: The anti-Müllerian hormone (AMH) plays an inhibitory role during folliculogenesis by regulating the number of follicles entering the growing pool. Antral follicle counts (AFC) are highly correlated with serum AMH concentrations and both appear to be related to the ovarian reserve in several species. Few data on AMH and AFC in mares exist, especially with regard to fertility. Therefore, the objective of the current study was to investigate the interrelationship between antral follicle count, serum AMH concentrations and fertility outcome in mares. One hundred and twenty-seven mares were enrolled in the study and grouped according to their reproductive status. Around time of estrus, serum AMH concentrations and AFC before and after ovulation were determined. Mares were artificially inseminated and pregnancy diagnosis was performed 14 to 18 days later. A high inter-individual variability in AFC and AMH concentration and a positive relationship between AMH and AFC for follicles ≤ 30 mm in diameter were observed, with a stronger correlation in mares older than 18 years. A high correlation between AFC measurements before and after ovulation was identified. The AFC after ovulation was higher than AFC before ovulation. AMH concentrations were neither related to the mares' reproductive status nor to age, number of cycles needed for pregnancy and pregnancy outcome. Excepted for a higher AFC in the middle-aged mares (9-18 years) compared to the younger mares (< 9 years), no associations between AFC and age, reproductive status as well as fertility of mares were found. This study confirms the relationship between AFC and AMH and a high degree of reproducibility of AFC measurements. However, based on our findings, neither AFC nor AMH are useful predictors of fertility in mares.


Assuntos
Hormônio Antimülleriano/sangue , Fertilidade/fisiologia , Cavalos , Folículo Ovariano/fisiologia , Envelhecimento/fisiologia , Animais , Feminino , Cavalos/sangue , Cavalos/fisiologia , Ovulação/fisiologia
11.
J Vet Med Sci ; 81(11): 1685-1687, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31548470

RESUMO

We examined the effect of human chorionic gonadotropin (hCG) treatment on double ovulation rate of first-wave follicles five days after estrus in lactating dairy cows. Cows were divided into two groups: 1) Ipsilateral group (IG; n=35), in which the first-wave dominant follicle (DF) was ipsilateral to the corpus luteum (CL), and 2) Contralateral group (CG; n=30), in which the first-wave DF was contralateral to the CL five days after estrus, then 1,500 IU of hCG was administrated. Double ovulation rate was significantly higher in the CG (26.7%) than in the IG (2.9%). This study demonstrate that the double ovulation rate of first-wave follicles was higher in the first-wave DF located in the contralateral ovary to the CL.


Assuntos
Bovinos , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/fisiologia , Estro/fisiologia , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Animais , Estro/efeitos dos fármacos , Feminino , Lactação , Folículo Ovariano/fisiologia , Ovulação/fisiologia
12.
Int J Mol Sci ; 20(19)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561408

RESUMO

Progesterone is widely used to induce maturation of isolated fully grown oocytes of the African clawed frog, Xenopus laevis. However, the hormone fails to release oocytes from the layer of surrounding follicle cells. Here, we report that maturation and follicle rupture can be recapitulated in vitro by treating isolated follicular oocytes with progesterone and low doses of the matrix metalloproteinase (MMP), collagenase, which are ineffective in the absence of the steroid. Using this in vitro ovulation model, we demonstrate that germinal vesicle breakdown (GVBD) and oocyte liberation from ovarian follicles occur synchronously during ovulation. Inhibition of the MAPK pathway in these experimental settings suppresses both GVBD and follicular rupture, whereas inhibition of MMP activity delays follicular rupture without affecting GVBD. These results highlight importance of MAPK and MMP activities in the ovulation process and provide the first evidence for their involvement in the release of oocytes from ovarian follicles in frogs. The in vitro ovulation model developed in our study can be employed for further dissection of ovulation.


Assuntos
Oócitos/fisiologia , Ovulação , Xenopus laevis/fisiologia , Animais , Técnicas de Cultura de Células , Células Cultivadas , Feminino , Hormônios Esteroides Gonadais , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/farmacologia , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Maturidade Sexual
13.
Biomed Res Int ; 2019: 8572837, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485447

RESUMO

Inhibin α (INHA) is a candidate gene controlling ovulation in poultry. As the functional center of inhibin, INHA is a molecular marker associated with egg-laying performance. The objective of the current study was to analyze the expression differences of INHA in reproductive system and single nucleotide polymorphisms (SNPs) associations with reproductive traits in chickens. A total of 260 LuHua chickens (barred-feather chicken) were adopted. Twelve SNPs were detected in INHA gene. Among the exonic SNPs, three (g. 22177991A>G, g. 22178249G>C, and g. 22178414G>A) were missense mutations, resulting in the amino acid substitutions Val→Ala, Ala→Gly, and Ala→Gly, respectively. Four SNPs in the 3' untranslated region of INHA were predicted to either disturb or create microRNA-target interactions. Five SNPs (g. 22176870T>C, g. 22177100T>C, g. 22177149T>C, g. 22177991A>G, and g. 22178975G>A) were significantly associated with the number of eggs at 300 d of age (EN) (P < 0.05). Birds carrying GA genotype exhibited more EN than those with AA genotype (P < 0.01). In addition, quantitative real-time PCR revealed that INHA is mainly expressed in follicles on d 300 in chickens. Firstly, INHA expression increased and then decreased. The highest INHA mRNA abundance was found in the fifth largest preovulatory follicle (F5) (P < 0.01). In the prehierarchical follicles, INHA mRNA expression increased dramatically in small yellow follicles (SYF) (P < 0.01). Western blotting analysis showed that the INHA protein expression profile in the follicle was similar to its mRNA counterpart with greater expression in F5 and SYF follicles and lowest expression in F1 follicles (P < 0.05). These results suggest that INHA is a potential candidate gene improving reproductive traits in chickens.


Assuntos
Galinhas/genética , Expressão Gênica/genética , Inibinas/genética , Polimorfismo de Nucleotídeo Único/genética , Reprodução/genética , Animais , Ovos , Feminino , Genótipo , Folículo Ovariano/fisiologia , Ovulação/genética , RNA Mensageiro/genética
14.
Anim Reprod Sci ; 209: 106137, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31514927

RESUMO

To evaluate follicular dynamics, there was assessment of superovulatory response and in vivo embryo production in ewes treated with relatively smaller doses of exogenous pFSH than typically used in combination with a dose of eCG at the beginning of the gonadotropin treatment period. Santa Inês ewes (n = 24) were randomly divided into three groups, based on mg dose of pFSH administered: G200 (n = 8), G133 (n = 8) and G100 (n = 8) in eight decreasing doses at 12 -h intervals. All ewes were treated with 300 IU of eCG concomitantly starting with first pFSH administration. Ovulatory follicular dynamics and follicular wall vascularization (FWV) were evaluated using a B-mode and color Doppler ultrasonic machine, respectively. Superovulatory response and embryo production were evaluated 6 days after estrous detection. In the G200 group, the preovulatory follicle size (PFS) were less (P <  0.05), ovulation time later (P <  0.05), and PFS rate greater (P <  0.05); while in the G100 group ovulation rate, and number and percentage of unfertilized eggs were greater (P <  0.05) than in the G133 group (P <  0.05). Number and percentage of viable embryos were greater in the G200 and G100 compared to G133 group (P <  0.05). The dose of 100 mg of FSH was as efficacious as the traditional dose of 200 mg, in combination with a dose of eCG, for superovulatory response and viable embryo production but there was a greater percentage of unfertilized eggs with this treatment.


Assuntos
Hormônio Foliculoestimulante/administração & dosagem , Inseminação Artificial , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Indução da Ovulação , Ovinos , Animais , Brasil , Tamanho Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Oogênese/efeitos dos fármacos , Oogênese/fisiologia , Folículo Ovariano/irrigação sanguínea , Ovulação/efeitos dos fármacos , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Gravidez , Ovinos/embriologia , Superovulação/fisiologia , Clima Tropical
15.
Anim Reprod Sci ; 208: 106105, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405457

RESUMO

South American camelids (SAC) are induced ovulating animals. In unmated females, ovarian follicle development occurs in waves of growth and regression, while mating when there is the presence of a mature follicle leads to ovulation. The capacity to respond to an ovulatory stimulus depends on the stage of the follicular wave development. Treatments to control ovarian follicular development have been performed to synchronize timing of wave emergence and development of the dominant follicle at a predictable time. Thus, synchronization of the time of follicular wave development allows for performing fixed time mating or artificial insemination, and superestimulatory treatments for multiple follicule development. Protocols are based on removal of the suppressive effect of the dominant follicle, that can be achieved by physical ablation or by inducing ovulation (with LH or GnRH) or atresia (with progesterone or progestagens alone or combined with estradiol) of this follicle. Differences between treatments should be taken into consideration when choosing a protocol for fixed time mating or artificial insemination, especially when applying the use these technologies for SAC production by commercial enterprises. Furthermore, the objective of applying synchronization protocols should be considered, because not all of these are effective in inhibiting follicular growth before initiation of a superestimulatory treatment for multiple follicle development.


Assuntos
Camelídeos Americanos/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Sincronização do Estro/métodos , Feminino , Inseminação Artificial , Indução da Ovulação
16.
Anim Reprod Sci ; 208: 106117, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405468

RESUMO

Based on ovarian and follicular variables, there was determination of ewes with different FecGE genotypes. Based on the FecGE genotype, 65 Santa Inês ewes were assigned to three experimental groups: homozygous wild-type (n = 25; FecG+/+), mutant heterozygous (n = 27; FecG+/E) and mutant homozygous (n = 13; FecGE/E). The ewe's ovaries were weighed and measured, then the follicles (oocyte, nucleus and nucleolus) were histologically evaluated for morphometry and morphology. Morphologically normal follicles, in the primordial and transitional stages, explained 70.18% of the variability morphological characteristics between mutant and wild-type ewes. Conducting the morphometric evaluation resulted in a more precise determination of the genotype groups when there was assessment of the primordial and secondary follicular developmental stages. The diameter of the oocyte and the oocyte nucleus of the primordial follicles explained 36.76% of the variability in follicular morphology between ewes with the mutation and those with the wildtype group. Similarly, the core diameter of oocytes in secondary follicles explained 10.63% of the variability in follicular morphology among FecGE/E, FecG+/E and FecG+/+ ewes. Thus, morphologically normal follicles in the primordial and transitional stages of development are the variables that allow for a more precise differentiation of Santa Inês ewes with the FecGE mutation. These variables may be evaluated to make more efficient the adoption of biotechniques that when conducted there is utilisation of follicles in the initial developmental stages as a physiological basis for classifying whether specific follicles are useful when conducting the techniques.


Assuntos
Fertilidade/genética , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Feminino , Regulação da Expressão Gênica/fisiologia , Genótipo , Ovinos/genética
17.
J Reprod Dev ; 65(5): 451-457, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31406064

RESUMO

This study aimed at investigating the efficacy of two protocols of estrous synchronization on follicular changes and hemodynamics. Pluriparous Egyptian buffaloes (n = 36) were synchronized either with controlled internal drug release (CIDR)-PGF2α (7-days CIDR insert with PGF2α injected on the 6th day; n = 18) or Ovsynch-CIDR (Ovsynch protocol concurrent with 7-days CIDR insert; n = 18). Blood sampling and ovarian ultrasound examinations (Grayscale, color and power Doppler modes) were conducted on the Day of CIDR removal, estrus, and luteal phase. Mean follicle diameter (MFD), first (1st-LF) and second (2nd-LF) largest follicle diameters, and E2 levels significantly increased in the CIDR-PGF2α group at CIDR withdrawal. Ovsynch-CIDR markedly fortified higher follicle population, MFD, and 1st-LF diameter at estrus and corpus luteum (CL) volume at the luteal phase in concomitant with increases (P < 0.05) in E2 (at estrus) and P4 (at luteal phase). At CIDR removal, the blue pixels in the dominant follicle (DF) were higher (1.5 times; P = 0.054) in the Ovsynch-CIDR than in the CIDR-PGF2α. At estrus, total blood flow (TBF) and power Doppler pixels (PDP) to DF(s) were noticeably higher (seven and 1.6 times; respectively) in the Ovsynch-CIDR than in CIDR-PGF2α (5906 ± 237 vs. 830 ± 60 pixels, P < 0.01 and 5479 ± 322 vs. 3377 ± 19 pixels, P < 0.05; respectively). At the luteal phase, TBF and PDP to the CL increased in the Ovsynch-CIDR group than in the CIDR-PGF2α group (11060 ± 965 vs. 7963 ± 480 pixels, 1.4 times, P = 0.05 and 18900 ± 1350 vs. 13220 ± 568 pixels, 1.1 times, P = 0.005; respectively). In conclusion, based on the improvement in synchronized follicular activity and hemodynamics, the Ovsynch-CIDR regimen is persuaded in Egyptian buffaloes.


Assuntos
Dinoprosta/administração & dosagem , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Animais , Cruzamento , Búfalos , Ciclo Estral/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Hemodinâmica , Fase Luteal/efeitos dos fármacos , Folículo Ovariano/diagnóstico por imagem , Esteroides/sangue , Ultrassonografia Doppler
18.
J Morphol ; 280(11): 1668-1681, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31433075

RESUMO

The dynamics of cellular development and homeostasis of the ovary depend on the balance between proliferation and cell death throughout the reproductive cycle. Millerichthys robustus is an annual fish whose ovarian follicles develop asynchronously, allowing daily reproduction from sexual maturity until death. The objective of this research is to describe, histologically, the processes of follicular atresia and regression of postovulatory follicular complexes (POC) throughout a reproductive cycle of M. robustus. Patterns of cell death were documented by apoptosis in atretic follicles and POC, and necrosis in the POC after ovulation with an associated inflammatory response. Atretic follicles were seen from the onset of sexual maturity, during week three post-hatching (PH), both in primary growth (from the Cortical alveoli step, with folliculogenesis completed) and secondary growth Stages, with a higher prevalence in the latter. POCs were observed in different stages of regression from week four PH until the death of the fish. The apoptotic characteristics found were: (i) fragmentation of the nuclear membrane and zona pellucida, and liquefaction of the cortical alveoli and yolk; (ii) follicular cells becoming phagocytic, increasing their size, and migrating within the oocyte; and (iii) formation of an intrafollicular lumen, a product of phagocytosis of the oocyte constituents and dispersed pigments that remain after the digestion of yolk and cortical alveoli. The morphological changes of the follicular cells of the POC, from a squamous morphology after ovulation to columnar during its regression with PAS+ contents, was documented, suggesting a secretory activity.


Assuntos
Apoptose , Ciprinodontiformes/fisiologia , Atresia Folicular , Folículo Ovariano/fisiologia , Animais , Ciprinodontiformes/anatomia & histologia , Feminino , Oócitos , Folículo Ovariano/anatomia & histologia , Reprodução
19.
J Assist Reprod Genet ; 36(9): 1823-1835, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376104

RESUMO

PURPOSE: Vitrification is a well-accepted fertility preservation procedure for cryopreservation of oocytes and embryos but little is known regarding ovarian tissue, for which slow freezing is the current convention. The aim of the present study was to assess the efficiency of non-equilibrium vitrification compared to conventional slow freezing for ovarian cortex cryopreservation. METHODS: Using prepubertal sheep ovaries, the capacity of the tissue to sustain folliculogenesis following cryopreservation and in vitro culture was evaluated. Ovarian cortex fragments were cultured in wells for 9 days, immediately or after cryopreservation by conventional slow freezing or non-equilibrium vitrification in straws. During culture, follicular populations within cortex were evaluated by histology and immunohistochemistry for PCNA and TUNEL. Steroidogenic activity of the tissue was monitored by assay for progesterone and estradiol in spent media. RESULTS: No significant differences in follicle morphology, PCNA, or TUNEL labeling were observed between cryopreservation methods at the initiation of culture. Similar decreases in the proportion of primordial follicle population, and increases in the proportion of growing follicles, were observed following culture of fresh or cryopreserved ovarian tissue regardless of cryopreservation method. At the end of culture, PCNA and TUNEL-positive follicles were not statistically altered by slow freezing or vitrification in comparison to fresh cultured fragments. CONCLUSIONS: Overall, for both cryopreservation methods, the cryopreserved tissue showed equal capacity to fresh tissue for supporting basal folliculogenesis in vitro. Taken together, these data confirm that both non-equilibrium vitrification and slow-freezing methods are both efficient for the cryopreservation of sheep ovarian cortex fragments.


Assuntos
Criopreservação/métodos , Folículo Ovariano , Ovário/fisiologia , Animais , Estradiol/metabolismo , Feminino , Preservação da Fertilidade/métodos , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , Progesterona/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Puberdade , Ovinos , Técnicas de Cultura de Tecidos , Vitrificação
20.
Theriogenology ; 138: 77-83, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31302434

RESUMO

This study evaluated the effect of leptin on the in vitro culture of isolated sheep early antral follicles. Early antral follicles (300-450 µm) were isolated and cultured for 12 days in tissue culture medium 199 (TCM 199) supplemented with glutamine, hypoxanthine, transferrin, insulin, selenium, ascorbic acid, bovine serum albumin (BSA) and recombinant follicle stimulating hormone (rFSH) (TCM 199+: control medium) or TCM 199+ supplemented with 2 or 10 ng/mL leptin. After culture, oocytes were subjected to in vitro maturation (IVM). The parameters analyzed were morphology, extrusion rate, follicular diameter, growth and fully-grown oocytes (oocytes ≥110 µm) rates. After IVM, reactive oxygen species (ROS) levels, mitochondrial activity, meiotic stages and meiotic resumption rates were also analyzed. After 12 days of culture, the concentration of 2 ng/mL of leptin showed a higher percentage of morphologically normal follicles, fully-grown oocytes (≥110 µm), active mitochondria and meiotic resumption compared to the control medium (TCM 199+; P < 0.05) but did not differ when compared to leptin concentration of 10 ng/mL (P > 0.05). After culturing, no significant differences existed among treatments in terms of the follicle diameter and ROS levels. In conclusion, the addition of 2 ng/mL leptin to the base culture medium is capable of improving follicular survival, oocyte growth, mitochondrial activity and meiotic resumption after the in vitro culture of isolated sheep early antral follicles.


Assuntos
Leptina/farmacologia , Mitocôndrias/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Animais , Células Cultivadas , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Mitocôndrias/fisiologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , Folículo Ovariano/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Ovinos
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