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1.
Methods Mol Biol ; 2218: 1-9, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606218

RESUMO

Zebrafish ovarian follicles are mainly composed of the oocyte and a thin layer of follicle cells. Recent studies have demonstrated extensive cell-cell interactions between the oocyte and surrounding follicle layer and that the two compartments communicate mostly through paracrine factors. To understand the paracrine communication within the follicle, it is essential to know the spatial expression patterns of genes in the two compartments. However, since the follicle layer is extremely thin and the oocytes are enormous in size in fish, it is often difficult to detect gene expression by traditional methods such as in situ hybridization. Separation of the oocyte and surrounding follicle layer followed by RT-PCR detection provides a sensitive way to reveal the expression of individual genes in the two compartments of the follicle. This chapter introduces a method for mechanic separation of the oocyte and follicle layer at full-grown stage for expression analysis. Since fish have similar follicle structure, this method may also be used in other species as well.


Assuntos
Expressão Gênica/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Peixe-Zebra/fisiologia , Animais , Feminino , Ovário/fisiologia , Comunicação Parácrina/fisiologia
2.
Methods Mol Biol ; 2218: 169-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606231

RESUMO

In some animal species, fertilization occurs through a funnel-like canal called the "micropyle." In teleost fishes, the micropyle is formed by a very specialized follicle cell, called the micropylar cell (MC). Very little is known about the mechanisms underlying the specification and differentiation of the MC, a unique cell among hundreds that compose the follicle cell layer. The Hippo pathway effector Taz is essential for this process and is the first reported MC marker. Here, we describe a method to identify and mark the micropylar cell following the immunostaining procedure on cryosections or combining it with the RNA in situ hybridization on whole-mount follicles.


Assuntos
Folículo Ovariano/fisiologia , Peixe-Zebra/fisiologia , Animais , Diferenciação Celular/fisiologia , Feminino , Fertilização/fisiologia , Masculino , Oócitos/metabolismo , Oócitos/fisiologia , Folículo Ovariano/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/fisiologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
3.
Poult Sci ; 100(2): 1098-1108, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518069

RESUMO

In contrast to the later stages of follicle development, little is known about the characteristics and mechanisms associated with early folliculogenesis in avian species. The objectives of the present study were to examine and compare the histomorphological and molecular changes of primordial, primary, and secondary follicles from duck and goose ovaries during the first 6 post-hatching week. Morphological analysis showed that the length and width of both duck and goose ovaries increased steadily during weeks 1 to 5 but increased acutely at week 6, whereas a greater increment was observed in the ovarian length of ducks than that of geese during weeks 4 to 5. Furthermore, smaller diameters of the 3 categories of follicles were observed in ducks than those in geese at the first appearance, but they reached a similar size at week 6. More importantly, secondary follicles were found in the ovaries of ducks 1 wk earlier than in those of geese. These results indicated a more rapid growth rate for ovarian follicles in ducks than in geese during early post-hatching development. At the molecular level, it was found that the mRNAs encoding follicle stimulating hormone receptor (FSHR), anti-Müllerian hormone (AMH), B-cell leukemia/lymphoma 2, and cysteine-dependent aspartate specific protease 3 (CASPASE3) were ubiquitously expressed in all ovarian follicles of ducks and geese with different expression profiles in each follicular category during the first 6 post-hatching week. Notably, transcript levels of FSHR, AMH, and CASPASE3 changed differently between ducks and geese during weeks 5 to 6, which was postulated to be one of the mechanisms inducing more rapid growth of ovarian follicles in ducks rather than in geese. In conclusion, our results revealed, for the first time, differences in early folliculogenesis, including the rate of growth of each follicular category and the timing of transition of primary to secondary follicles, between ducks and geese, and these differences could result from different expression profiles of FSHR, AMH, and CASPASE3 during early post-hatching development.


Assuntos
Patos/fisiologia , Gansos/fisiologia , Folículo Ovariano/fisiologia , Ovário/anatomia & histologia , Transcriptoma/fisiologia , Animais , Patos/anatomia & histologia , Patos/genética , Feminino , Gansos/anatomia & histologia , Gansos/genética , RNA/química , RNA/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária
4.
Trop Anim Health Prod ; 53(1): 102, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33417076

RESUMO

The present study was aimed at evaluating the differences of ovarian follicular dynamics and circulating progesterone (P4) concentrations between crossbred Holstein heifers that ovulated and did not ovulate after a P4-based synchronization protocol. Twenty-one crossbred (Holstein × Thai native) heifers with random stages of the oestrous cycle were subjected to the ovulation synchronization protocol, using an intravaginal P4-releasing device (Eazi-Breed CIDR®) for 7 days. Out of 21 CIDR-treated heifers, 14 ovulating heifers were classified as the ovulatory group and 7 non-ovulating heifers were considered the anovulatory group. The heifers having new wave emergence in ovulatory and anovulatory groups were 11/14 (78.6%) and 4/7 (57.1%), respectively. In ovulating heifers, the mean (± SEM) diameter of preovulatory follicle (PF, mm) was significantly larger, compared to non-ovulating heifers (7.21 ± 0.32 versus 4.04 ± 0.44; P = 0.001), while the mean (± SEM) follicular growth rates (mm/d) in non-ovulating heifers tended to be lower, compared to ovulating heifers (0.73 ± 0.17 versus 1.06 ± 0.08; P = 0.07). The mean (± SEM) circulating P4 concentration (ng/ml) throughout the CIDR protocol (0-10 days) in non-ovulating heifers was significantly higher, in comparison with ovulating heifers (2.82 ± 0.27 versus 1.83 ± 0.16; P = 0.02). However, no significant difference in the mean corpus luteum volume between groups was observed. In conclusion, the present results suggested that elevated circulating P4 concentrations and smaller PF diameters could cause ovulation failure in crossbred Holstein heifers, following a 7-day CIDR-based synchronization protocol.


Assuntos
Bovinos/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Progesterona/sangue , Animais , Ciclo Estral , Sincronização do Estro , Feminino
5.
PLoS Biol ; 18(12): e3001025, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351795

RESUMO

Primordial follicle assembly in the mouse occurs during perinatal ages and largely determines the ovarian reserve that will be available to support the reproductive life span. The development of primordial follicles is controlled by a complex network of interactions between oocytes and ovarian somatic cells that remain poorly understood. In the present research, using single-cell RNA sequencing performed over a time series on murine ovaries, coupled with several bioinformatics analyses, the complete dynamic genetic programs of germ and granulosa cells from E16.5 to postnatal day (PD) 3 were reported. Along with confirming the previously reported expression of genes by germ cells and granulosa cells, our analyses identified 5 distinct cell clusters associated with germ cells and 6 with granulosa cells. Consequently, several new genes expressed at significant levels at each investigated stage were assigned. By building single-cell pseudotemporal trajectories, 3 states and 1 branch point of fate transition for the germ cells were revealed, as well as for the granulosa cells. Moreover, Gene Ontology (GO) term enrichment enabled identification of the biological process most represented in germ cells and granulosa cells or common to both cell types at each specific stage, and the interactions of germ cells and granulosa cells basing on known and novel pathway were presented. Finally, by using single-cell regulatory network inference and clustering (SCENIC) algorithm, we were able to establish a network of regulons that can be postulated as likely candidates for sustaining germ cell-specific transcription programs throughout the period of investigation. Above all, this study provides the whole transcriptome landscape of ovarian cells and unearths new insights during primordial follicle assembly in mice.


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Ovário/metabolismo , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas , Células da Granulosa/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/metabolismo , Folículo Ovariano/fisiologia , Ovário/citologia , Gravidez , Análise de Célula Única/métodos , Transcriptoma/genética
6.
J Vis Exp ; (161)2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32716390

RESUMO

The limited reserve of mature, fertilizable oocytes represents a major barrier for the success of assisted reproduction in mammals. Considering that during the reproductive life span only about 1% of the oocytes in an ovary mature and ovulate, several techniques have been developed to increase the exploitation of the ovarian reserve to the growing population of non-ovulatory follicles. Such technologies have allowed interventions of fertility preservation, selection programs in livestock, and conservation of endangered species. However, the vast potential of the ovarian reserve is still largely unexploited. In cows, for instance, some attempts have been made to support in vitro culture of oocytes at specific developmental stages, but efficient and reliable protocols have not yet been developed. Here we describe a culture system that reproduce the physiological conditions of the corresponding follicular stage, defined to develop in vitro growing oocytes collected from bovine early antral follicles to the fully-grown stage, corresponding to the medium antral follicle in vivo. A combination of hormones and a phosphodiesterase 3 inhibitor was used to prevent untimely meiotic resumption and to guide oocyte's differentiation.


Assuntos
Técnicas de Cultura de Células/métodos , Oócitos/fisiologia , Reserva Ovariana/fisiologia , Reprodução/fisiologia , Animais , Bovinos , Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Feminino , Oogênese/fisiologia , Folículo Ovariano/fisiologia , Ovário/citologia , Ovário/fisiologia
7.
Gynecol Obstet Invest ; 85(3): 290-294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32485714

RESUMO

AIM: This study evaluated the competency of oocytes/embryos derived from follicles >15 mm in diameter from obese patients, compared with nonobese patients. PATIENTS AND METHODS: A cohort study was conducted in a single tertiary medical center between July 2018 and May 2019. Before ultrasound-guided follicular aspiration, follicles were measured and those with maximal dimensional size >15 mm were tracked. Microscopic examination of the follicular aspirates was performed by an embryologist. Each follicle aspirated was evaluated for oocyte maturation, oocyte fertilization, and embryo quality. RESULTS: 457 follicles were measured: 380 (83.2%) in nonobese and 77 (16.8%) in obese patients. No in-between group differences were observed in the causes of infertility, patients' demographics, or ovarian stimulation characteristics. Oocytes were achieved during aspiration from 277 (72.8%) and 54 (70.0%) of the nonobese and obese groups, respectively (p = 0.67). No in-between group differences were observed in fertilization (2PN/oocyte), top quality embryo (TQE) per zygote (2PN), and TQE per follicle. CONCLUSION: Oocyte recovery rate from follicles >15 mm is unrelated to patients' BMI. Moreover, the oocytes recovered from obese patients are competent yielding comparable zygote and TQE per follicle/oocyte, compared with nonobese patients. Further investigation is required to strengthen this finding.


Assuntos
Infertilidade/fisiopatologia , Obesidade/fisiopatologia , Recuperação de Oócitos/estatística & dados numéricos , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Adulto , Índice de Massa Corporal , Estudos de Coortes , Embrião de Mamíferos , Feminino , Humanos , Infertilidade/etiologia , Obesidade/complicações , Recuperação de Oócitos/métodos , Indução da Ovulação
8.
Proc Natl Acad Sci U S A ; 117(22): 12174-12181, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32409601

RESUMO

Germ cells have the ability to differentiate into eggs and sperm and must determine their sexual fate. In vertebrates, the mechanism of commitment to oogenesis following the sexual fate decision in germ cells remains unknown. Forkhead-box protein L3 (foxl3) is a switch gene involved in the germline sexual fate decision in the teleost fish medaka (Oryzias latipes). Here, we show that foxl3 organizes two independent pathways of oogenesis regulated by REC8 meiotic recombination protein a (rec8a), a cohesin component, and F-box protein (FBP) 47 (fbxo47), a subunit of E3 ubiquitin ligase. In mutants of either gene, germ cells failed to undergo oogenesis but developed normally into sperm in testes. Disruption of rec8a resulted in arrest at a meiotic pachytenelike stage specifically in females, revealing a sexual difference in meiotic progression. Analyses of fbxo47 mutants showed that this gene regulates transcription factors that facilitate folliculogenesis: LIM homeobox 8 (lhx8b), factor in the germline α (figla), and newborn ovary homeobox (nobox). Interestingly, we found that the fbxo47 pathway ensures that germ cells do not deviate from an oogenic pathway until they reach diplotene stage. The mutant phenotypes together with the timing of their expression imply that germline feminization is established during early meiotic prophase I.


Assuntos
Proteínas de Peixes/metabolismo , Células Germinativas/citologia , Gônadas/embriologia , Oogênese , Oryzias/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/fisiologia , Gônadas/metabolismo , Masculino , Meiose , Folículo Ovariano/citologia , Processos de Determinação Sexual , Espermatogênese , Espermatozoides/citologia
9.
PLoS One ; 15(5): e0232120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407351

RESUMO

Decades of work indicate that female birds can control their offspring sex ratios in response to environmental and social cues. In laying hens, hormones administered immediately prior to sex chromosome segregation can exert sex ratio skews, indicating that these hormones may act directly on the germinal disc to influence which sex chromosome is retained in the oocyte and which is discarded into an unfertilizable polar body. We aimed to uncover the gene pathways involved in this process by testing whether treatments with testosterone or corticosterone that were previously shown to influence sex ratios elicit changes in the expression of genes and/or gene pathways involved in the process of meiotic segregation. We injected laying hens with testosterone, corticosterone, or control oil 5h prior to ovulation and collected germinal discs from the F1 preovulatory follicle in each hen 1.5h after injection. We used RNA-sequencing (RNA-seq) followed by DESeq2 and gene set enrichment analyses to identify genes and gene pathways that were differentially expressed between germinal discs of control and hormone-treated hens. Corticosterone treatment triggered downregulation of 13 individual genes, as well as enrichment of gene sets related to meiotic spindle organization and chromosome segregation, and additional gene sets that function in ion transport. Testosterone treatment triggered upregulation of one gene, and enrichment of one gene set that functions in nuclear chromosome segregation. This work indicates that corticosterone can be a potent regulator of meiotic processes and provides potential gene targets on which corticosterone and/or testosterone may act to influence offspring sex ratios in birds.


Assuntos
Corticosterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Meiose/efeitos dos fármacos , Meiose/genética , Folículo Ovariano/citologia , Ovulação , Testosterona/farmacologia , Animais , Galinhas , Feminino , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia
10.
Proc Natl Acad Sci U S A ; 117(21): 11531-11540, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32414916

RESUMO

A polarized architecture is central to both epithelial structure and function. In many cells, polarity involves mutual antagonism between the Par complex and the Scribble (Scrib) module. While molecular mechanisms underlying Par-mediated apical determination are well-understood, how Scrib module proteins specify the basolateral domain remains unknown. Here, we demonstrate dependent and independent activities of Scrib, Discs-large (Dlg), and Lethal giant larvae (Lgl) using the Drosophila follicle epithelium. Our data support a linear hierarchy for localization, but rule out previously proposed protein-protein interactions as essential for polarization. Cortical recruitment of Scrib does not require palmitoylation or polar phospholipid binding but instead an independent cortically stabilizing activity of Dlg. Scrib and Dlg do not directly antagonize atypical protein kinase C (aPKC), but may instead restrict aPKC localization by enabling the aPKC-inhibiting activity of Lgl. Importantly, while Scrib, Dlg, and Lgl are each required, all three together are not sufficient to antagonize the Par complex. Our data demonstrate previously unappreciated diversity of function within the Scrib module and begin to define the elusive molecular functions of Scrib and Dlg.


Assuntos
Polaridade Celular/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila , Células Epiteliais , Proteínas de Membrana/fisiologia , Animais , Drosophila/citologia , Drosophila/fisiologia , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Epitélio/fisiologia , Feminino , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , Proteína Quinase C , Proteínas Supressoras de Tumor
11.
Poult Sci ; 99(5): 2746-2756, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359612

RESUMO

This study determined, for the first time, the different subpopulations of germ cells and stereological changes within the cortex of the functional left ovary during germ cell nest breakdown, and formation of the primordial follicle pool in the domestic turkey. This was accomplished by measuring the size, density, and count of prefollicular germ cells and primordial follicles in turkey poults between 1 and 35 days posthatch (dph). The percent volume (PV) of germ cells and follicles within the cortex was also calculated as a means of validating the counting technique. The total percent volume of germ cells and primordial follicles within the cortex ranged between 42 and 84%, suggesting that the counting technique was valid. Our findings show that before germ cell nest breakdown (5 dph), there were roughly 1,000,000 prefollicular germ cells within the cortex of the left ovary and that germ cell nest breakdown initiated between 5 and 7 dph, characterized by a decrease (P ≤ 0.001) in prefollicular germ cell density and the subsequent appearance of primordial follicles. Nest breakdown is followed on day 9 by the first increase (P ≤ 0.05) in size of prefollicular germ cells. These cells continue to grow throughout nest breakdown. The majority (>90%) of germ cell nest breakdowns concluded by 15 dph; although, the primordial follicle pool was not fully established until 35 dph, as determined by a total lack of prefollicular germ cells. At this point, the pool was comprised of an estimated 60,000 primordial follicles and shows that during nest breakdown and follicle pool formation, ∼94% of germ cells were lost. This 94% decrease in the number of germ cells during nest breakdown in the turkey is comparable to the domestic chicken but is greater than the average two-thirds which are lost in mammalian species.


Assuntos
Células Germinativas/fisiologia , Folículo Ovariano/fisiologia , Perus/fisiologia , Animais , Feminino
12.
Anim Sci J ; 91(1): e13384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32462805

RESUMO

To understand the ovarian basis for prolificacy of Bonga sheep, a total of 31 ewes were selected based on litter size (LS) records and divided into two groups: High Prolificacy (HP) (n = 20) with LS ≥ 2 and Low Prolificacy (LP) (n = 11) with LS = 1. At a synchronized estrus, follicular dynamics were determined using transrectal ultrasonography. Plasma estradiol concentrations were also monitored. In total 27 ewes were observed in estrus being 9/11 LP (82%) and 18/20 HP (90%). On the day of estrus (day 0), the mean number of large follicles was higher (p < .05) in HP (1.78 ± 0.19) than in LP (1.0 ± 0.28) ewes. Prior to estrus, more (p < .05) medium follicles were visible for HP compared to LP ewes. Plasma estradiol concentrations were higher in HP compared to LP ewes (18.91 ± 0.41 vs. 14.51 ± 0.65 pg/ml; p < .05) and similarly was ovulation number (2.3 ± 0.15 vs. 1.28 ± 0. 14; p < .05). Higher ovulation rates and litter size in Bonga sheep are evidenced by the previous presence of more large follicles and the existence of co-dominance effects as most likely medium follicles are selected to ovulate.


Assuntos
Tamanho da Ninhada de Vivíparos , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Ovinos/fisiologia , Animais , Estradiol/sangue , Estro/fisiologia , Feminino
13.
Sci China Life Sci ; 63(6): 849-865, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32291558

RESUMO

The number of growth factors involved in female fertility has been extensively studied, but reluctance to add essential growth factors in culture media has limited progress in optimizing embryonic growth and implantation outcomes, a situation that has ultimately led to reduced pregnancy outcomes. Insulin-like growth factor II (IGF-II) is the most intricately regulated of all known reproduction-related growth factors characterized to date, and is perhaps the predominant growth factor in human ovarian follicles. This review aims to concisely summarize what is known about the role of IGF-II in follicular development, oocyte maturation, embryonic development, implantation success, placentation, fetal growth, and in reducing placental cell apoptosis, as well as present strategies that use growth factors in culture systems to improve the developmental potential of oocytes and embryos in different species. Synthesizing the present knowledge about the physiological roles of IGF-II in follicular development, oocyte maturation, and early embryonic development should, on the one hand, deepen our overall understanding of the potential beneficial effects of growth factors in female reproduction and on the other hand support development (optimization) of improved outcomes for assisted reproductive technologies.


Assuntos
Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/fisiologia , Reprodução/fisiologia , Animais , Desenvolvimento Embrionário/fisiologia , Feminino , Desenvolvimento Fetal/fisiologia , Regulação da Expressão Gênica , Humanos , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Gravidez
14.
In Vivo ; 34(2): 533-541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32111751

RESUMO

BACKGROUND/AIM: Transportation of ovarian cortex prior to freezing is used clinically; however, basic investigations of ovarian storage are limited and the question remains what temperature is optimal for transport over long distances and time periods. The aim of this study was to evaluate the rate of follicular loss over various time periods under two different temperatures and assess whether ovarian follicle viability is affected following cryopreservation and thawing subsequent to the transportation of ovarian tissue. MATERIALS AND METHODS: Pig ovaries were transported at 4°C (n=10) or at 38°C (n=10) prior to cryopreservation. At 0, 4, 12 and 24 h tissues were fixed for histological examination and a LIVE/DEAD Assay. At the same time-points ovarian tissues were cryopreserved and analysed after thawing. RESULTS: Histological evaluation and LIVE/DEAD Assay of freshly transported ovarian tissue showed significantly better follicle survival at 4°C during transportation duration. In cryopreserved ovarian tissues the LIVE/DEAD Assay showed a significant difference in the number of intact and dead follicles at 24 h in favor of 4°C (p<0.05). CONCLUSION: Ovarian tissue transportation should be kept at a minimum to prevent potential damage.


Assuntos
Sobrevivência Celular , Folículo Ovariano/fisiologia , Ovário/fisiologia , Temperatura , Animais , Biomarcadores , Temperatura Corporal , Criopreservação , Feminino , Preservação da Fertilidade , Humanos , Imuno-Histoquímica , Folículo Ovariano/citologia , Ovário/citologia , Suínos
15.
Maturitas ; 134: 34-40, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32143774

RESUMO

OBJECTIVES: To evaluate the prognostic value of anti-Mullerian hormone (AMH) levels in estimating the ovarian density of primordial and primary follicles, which can be assumed to reflect the real ovarian reserve. STUDY DESIGN: A total of 537 women, average age 30.4 years (range 8.0-43.7 years), underwent ovarian tissue cryopreservation prior to gonadotoxic therapies due to malignant diseases which do not affect ovarian reserve parameters. Standardized ovarian biopsies were obtained, and follicular density was analysed. The prognostic accuracy of serum AMH in estimating ovarian follicle density was evaluated. MAIN OUTCOME MEASURES: Histologically determined follicle density, AMH serum concentration and their correlation. RESULTS: In children, follicle density was high but AMH concentration was low. AMH concentration was predicted to be maximum at the age of 15.5 years. In women aged over 15.5 years, the relationship between AMH concentration and follicle density was evaluated. Crude analysis revealed that serum AMH levels and follicular density were moderately correlated (r = 0.34, p < 0.001). From the adjusted regression model the predicted value of follicle density of women aged 20, 30 and 40 years as well as the associated 50 % and 95 % prediction intervals (50 % PI and 95 % PI, respectively) were calculated. For example, for women aged 40 years with a serum AMH level of 1 ng/ml, a follicle density of 2.3/mm3 (50 %PI: [1.1, 4.6]; 95 %PI: [0.3, 18]) was predicted. These large prediction intervals demonstrate the low predictive value of serum AMH for the ovarian follicle density. CONCLUSIONS: Serum AMH levels have limited prognostic value for the follicle density and therefore for the real ovarian reserve.


Assuntos
Hormônio Antimülleriano/sangue , Folículo Ovariano/fisiologia , Reserva Ovariana , Adolescente , Adulto , Biópsia , Criança , Criopreservação , Feminino , Humanos , Menopausa Precoce/sangue , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/diagnóstico , Prognóstico , Análise de Regressão , Adulto Jovem
16.
Fertil Steril ; 113(3): 609-617.e3, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32192593

RESUMO

OBJECTIVE: To evaluate whether specific ovarian decortication techniques vary in promoting ovarian cortex cryopreservation and transplant outcomes. DESIGN: Experimental design. SETTING: University hospital. ANIMAL(S): Nonobese diabetic (NOD)/severe combined immunodeficiency (SCID) female mice. INTERVENTION(S): Human ovarian biopsy samples allocated to one of the following decortication procedures: scratching with scalpel blade (B), cutting with microsurgical scissors (M), separation with slicer (S), or no-separation (control, C). Parallel, in vivo experiment: decortication techniques combined with slow freezing (SF) and vitrification (VT) before xenograft into immunodeficient mice. MAIN OUTCOME MEASURE(S): Follicular counts, apoptosis, shear stress, Hippo pathway and inflammation. In vivo: recovered grafts analyzed for follicular counts, angiogenesis, proliferation, and fibrosis. RESULT(S): There were no differences in follicular density or number of damaged follicles between the decortication techniques in the in vitro study. Nevertheless, the M samples showed statistically significantly increased stromal damage compared with the controls and S samples, and up-regulation of Hsp60 shear stress gene expression. Decortication by both M and S inhibited the Hippo pathway, promoting gene expression changes. In the 21-day xenograft, total follicular density statistically significantly decreased compared with the nongrafted controls in all groups. Nevertheless, no differences were observed between the decortication techniques. Ovarian stroma vascularization was increased in the vitrified samples, but among the slow-freezing samples, the B samples had the lowest microvessel density. The M decorticated xenografts had increased fibrosis. CONCLUSION(S): Decortication with a slicer causes less damage to ovarian tissue than other commonly used methods although microsurgical scissors seem to preserve slightly increased follicular numbers. Nevertheless, blade decortication seems to be a reliable technique for maintaining acceptable follicular conditions without inducing serious stromal impairment.


Assuntos
Separação Celular/normas , Criopreservação/normas , Folículo Ovariano/fisiologia , Ovário , Células Estromais/citologia , Coleta de Tecidos e Órgãos/normas , Adolescente , Adulto , Animais , Calibragem , Separação Celular/métodos , Sobrevivência Celular , Criopreservação/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Folículo Ovariano/citologia , Controle de Qualidade , Coleta de Tecidos e Órgãos/métodos , Adulto Jovem
17.
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
19.
Anim Reprod Sci ; 213: 106281, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31987316

RESUMO

The objectives were to evaluate effects of tropical seasons on thermal biology, preovulatory follicle (POF) diameter, POF and luteal vascularities, and estradiol (E2) and progesterone (P4) concentrations; and to determine the associations among the values for these variables during preovulatory and postovulatory periods in Thai native cows in tropical climates: cold, hot, and rainy seasons. Development and vascularity of the POF and corpora lutea (CL) were evaluated using color Doppler ultrasonography. The temperature-humidity index (THI) was greater when the preovulatory period occurred during the rainy season when compared with the occurrence during the hot and cold seasons of the year. Furthermore, POF diameter was less when the THI was greater. The THI was greater when the postovulatory period occurred during the rainy season when compared to the occurrence of the postovulatory period during the hot and cold seasons of the year. Furthermore, the CL vascularity and P4 concentration were less when the THI was greater. The THI was inversely correlated with CL vascularity and P4 concentrations. When the THI was greatest during the hot and rainy seasons of the year, there were the greatest negative effects on POF size, POF and CL blood flow, and concentrations of E2 and P4 during the preovulatory and postovulatory periods. While native Bos indicus are capable of adapting to tropical conditions, there are still negative effects, such as impaired POF and CL functions, when the THI induces heat stress.


Assuntos
Bovinos/fisiologia , Corpo Lúteo/irrigação sanguínea , Folículo Ovariano/irrigação sanguínea , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Temperatura , Animais , Feminino , Estações do Ano , Clima Tropical
20.
J Ovarian Res ; 13(1): 7, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926556

RESUMO

BACKGROUND: The timing of the first postpartum ovulation is an important factor affecting the timing of estrous resumption in dairy cows. The first postpartum ovulation is delayed in cows producing large amounts of milk with an intensive negative energy balance. The antral follicle count (AFC) and serum anti-Müllerian hormone concentrations are known to be indicators of the ovarian reserve, which is the number and quality of follicles left in a pair of ovaries and known as an indicator of female fertility. Cows with higher AFC have been proven to show higher pregnancy rate and shorter calving to conception intervals; however, the relationship between the timing of the first postpartum ovulation and ovarian reserve remains unclear. Therefore, this study examined the relationships between postpartum follicular dynamics, the ovarian cycle, nutritional status, and ovarian reserve. METHODS: Transrectal ultrasonography was conducted from calving to 70-120 days in milk (DIM) in 26 cows to monitor AFC, follicular dynamics and the ovarian cycle. Body weight (BW) and milk yield were used as indicators of nutritional status. RESULTS: The first postpartum ovulation was significantly later in cows with low AFC (< 25) than in those with high AFC (≥25), while changes in BW from calving to the nadir and milk production were similar in both groups. The present results also suggested that cows with low AFC and a delayed first postpartum ovulation had a shorter first ovarian cycle after the first postpartum ovulation. The mean DIM of the first postpartum artificial insemination (AI) and days open (days from calving to AI with which pregnancy was achieved) were similar in high and low AFC groups. CONCLUSIONS: The first postpartum ovulation was significantly earlier in cows with high AFC than in those with low AFC. The assumed reason for this result was higher sensitivity to luteinizing hormone and larger androstenedione and estradiol production in follicles in high AFC cows. Therefore, cows with high AFC may be more fertile than those with low AFC while their milk production increase and BW decrease; it means they are in negative energy balance. (340/350 words).


Assuntos
Ciclo Estral/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Período Pós-Parto/fisiologia , Animais , Hormônio Antimülleriano/sangue , Peso Corporal/fisiologia , Bovinos , Contagem de Células , Feminino , Hormônios/metabolismo , Leite/metabolismo , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Reserva Ovariana/fisiologia , Gravidez , Taxa de Gravidez , Fatores de Tempo
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