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1.
Theriogenology ; 107: 95-103, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29145066

RESUMO

The search for non-invasive signs of oocyte meiotic competence is very important for the development of in vitro follicle culture (IVFC) systems. The aims of the present study were: (1) to investigate the effect of in vitro maturation (IVM) of in vivo grown goat COCs, in group or individually, on oocyte chromatin configuration (Experiment 1), and (2) the influence of IVFC period (12 vs. 18 days) on the ability of the oocyte to resume meiosis immediately after IVFC (before in vitro maturation; IVM), or after IVM (Experiment 2). In experiment 1, in vivo grown cumulus-oocyte complexes (COCs) were submitted to IVM in groups (10 COCs/100 µL-drop) or individually (1 COC/10 µL-drop), and chromatin configuration was assessed. In experiment 2, isolated follicles were individually cultured for 12 or 18 days, and submitted to individual IVM afterwards. The following end points were evaluated: follicular growth and morphology, oocyte diameter, viability and chromatin configuration, as well as individual follicular estradiol production. Similar maturation rates were obtained between in vivo grown COCs matured individually and in groups (66.7% vs. 63.6%, respectively) (Experiment 1). Only after 18 days of IVFC, oocytes were able to grow during IVM, reaching a mean oocyte diameter of 119 µm. Also, this treatment produced the highest rate of metaphase II oocytes (46.2% out of the total number of cultured follicles). Finally, it was observed that follicles with a daily growth rate >7.1 µm/day (fast-growing) and that reached at least 600 µm in diameter, were more likely (P < 0.05) to produce oocytes capable of attaining MII. In conclusion, caprine oocytes can be individually matured in vitro, as efficiently as in groups. This result was essential to pair in vitro follicle development and in vitro oocyte maturation with specific individual follicles. Using this approach, it was possible to establish non-invasive signs for the efficiency of IVFC based on follicle daily growth rate and diameter, and oocyte diameter: follicle daily growth >7 µm, follicle diameter of at least 600 µm, and oocyte diameter ≥120 µm. In addition, 18 days seems to be the most suitable culture time for caprine early antral follicles.


Assuntos
Cabras/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Meiose/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Animais , Tamanho Celular , Cromatina , Estradiol/metabolismo , Feminino , Oócitos/citologia
2.
Anim Reprod Sci ; 185: 118-127, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28882328

RESUMO

The aim of the present study was to investigate the influence of two insulin concentrations (10ng/mL and 10µg/mL) combined or in the absence of BMP15 and/or GDF9, on the in vitro survival and development of preantral follicles of goat ovarian tissue. Ovarian slices from the same goat ovary pair were randomly assigned to a non-cultured control treatment or to be in vitro cultured for 1 or 7days in α-MEM containing 10ng/mL (Low) or 10µg/mL (High) of insulin in the absence or presence of BMP15 and/or GDF9. With the low insulin treatment, there was a greater percentage of normal follicles than with the high insulin treatment. The addition of BMP15 alone or in association with GDF9 to the medium containing low insulin resulted in a lesser percentage of normal follicles (P<0.05). The addition of BMP15 and GDF9 separately or in combination with the high insulin concentration enhanced the percentage of normal follicles. On day 7 of culture, the use of medium containing low insulin alone or high insulin supplemented with BMP15 and BMP15+GDF9 resulted in a greater percentage of secondary follicles than the non-cultured control, although follicles cultured with low insulin were smaller than those from the control group and had greater rates of oxidative stress. In conclusion, in the presence of physiological concentrations of insulin (10ng/mL), medium supplementation with GDF9 and BMP15 alone or in combination is unnecessary for normal follicle development in vitro.


Assuntos
Proteína Morfogenética Óssea 15/farmacologia , Cabras , Fator 9 de Diferenciação de Crescimento/farmacologia , Insulina/farmacologia , Folículo Ovariano/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Insulina/administração & dosagem , Folículo Ovariano/fisiologia
3.
Theriogenology ; 87: 321-332, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27729112

RESUMO

The aim of the present study was to evaluate the effect of growth hormone (GH) and vascular endothelial growth factor (VEGF) added alone, sequentially or in combination, in the presence of insulin at physiological concentration (10 ng/mL) on the IVC of two different follicular categories: preantral (experiment 1; Exp.1) and early antral (experiment 2; Exp.2). Isolated follicles were individually cultured for 24 (Exp.1) and 18 days (Exp.2) in the following treatments: αMEM+ (Control), or Control medium supplemented with 50 ng/mL GH (GH), 100 ng/mL VEGF (VEGF), the combination of both (GH + VEGF), GH during the first 12 days and VEGF from Day 12 until the end of the culture (GH/VEGF) and vice versa (VEGF/GH). At the end of the culture, cumulus-oocyte complexes from in vitro-grown follicles were recovered and subjected to IVM. The following end points were evaluated: Follicle morphology, growth rates and antrum formation, production of estradiol, progesterone and testosterone, oocyte viability and meiotic stage, as well as relative expression of LHR, Amh, HAS2, PTGS2, CYP17, CYP19A1, and 3ßHSD. A considerable amount of viable fully grown oocytes were recovered after the IVC of early antral follicles in all treatments. Nevertheless, the GH treatment presented the highest percentage of fully grown oocytes (60%), mean oocyte diameter (117.74 ± 2.61 µm), and meiotic resumption (50%). Furthermore, GH treatment produced higher (P < 0.05) rates of metaphase II oocytes than all the other treatments, and similar LHR, Amh, and PTGS2 transcript levels to in vivo. Contrary to early antral follicles, preantral follicles were not affected by medium supplementation. In conclusion, the addition of GH to a culture medium containing physiological concentrations of insulin improves oocyte growth and maturation after the IVC of goat early antral follicles.


Assuntos
Cabras , Hormônio do Crescimento/farmacologia , Folículo Ovariano/fisiologia , Técnicas de Cultura de Tecidos/veterinária , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Meios de Cultura , Estradiol/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Progesterona/metabolismo , Testosterona/metabolismo , Técnicas de Cultura de Tecidos/métodos
4.
Andrologia ; 44 Suppl 1: 362-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21762188

RESUMO

Lepidium meyenii (maca) is a plant that grows exclusively above 4000 m in the Peruvian central Andes. Red maca (RM) extract significantly reduced prostate size in rats with benign prostatic hyperplasia (BPH) induced by testosterone enanthate (TE). Zinc is an important regulator of prostate function. This study aimed to determine the effect of RM on prostate zinc levels in rats with BPH induced by TE. Also, the study attempted to determine the best marker for the effect of RM on sex accessory glands. Rats treated with RM extract from day 1 to day 14 reversed the effect of TE administration on prostate weight and zinc levels. However, RM administered from day 7 to day 14 did not reduce the effect of TE on all studied variables. Finasteride (FN) reduced prostate, seminal vesicle and preputial gland weights in rats treated with TE. Although RM and FN reduced prostate zinc levels, the greatest effect was observed in TE-treated rats with RM from day 1 to day 14. In addition, prostate weight and zinc levels showed the higher diagnosis values than preputial and seminal vesicle weights. In conclusion, RM administered from day 1 to day 14 reduced prostate size and zinc levels in rats where prostatic hyperplasia was induced with TE. Also, this experimental model could be used as accurately assay to determine the effect of maca obtained under different conditions and/or the effect of different products based on maca.


Assuntos
Lepidium/química , Extratos Vegetais/farmacologia , Próstata/efeitos dos fármacos , Hiperplasia Prostática/induzido quimicamente , Testosterona/efeitos adversos , Zinco/metabolismo , Animais , Finasterida/farmacologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Ratos , Ratos Sprague-Dawley
5.
Andrologia ; 44 Suppl 1: 205-12, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21651603

RESUMO

Mashua is an edible-tuber crop that grows in the Andean region. Folk medicine describes the use of mashua to reduce reproductive function in men. The present study aimed: (i) to determine whether different doses of mashua (0.01, 0.1, 1 and 2 g kg(-1)) produced a dose-response reduction on sperm production and quality; and, (ii) to determine whether these anti-reproductive effects of mashua can be reversible after cessation of treatment (12 and 24 days of recovery time). Mashua-treated rats showed lower values of daily sperm production, epididymal and vas deferens sperm count and sperm motility; meanwhile, mashua increased the percentage of abnormal sperm morphology and epididymal sperm transit rate. The following variables follow a dose-response effect: sperm number in vas deferens, sperm motility and sperm transit rate. In addition, it was demonstrated that the reduction in reproduction function in male rats treated with mashua was reversible after 24 days of recovery time. Finally, lower doses mashua reduces sperm number and quality (motility and morphology), and these adverse effects on male reproductive system may be reversible after 24 days after cessation of the treatment.


Assuntos
Extratos Vegetais/farmacologia , Espermatozoides/efeitos dos fármacos , Tropaeolum/química , Animais , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos
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