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1.
Sheng Wu Gong Cheng Xue Bao ; 36(4): 632-642, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32347058

RESUMO

Extracellular vesicles (EVs) refer to bilayer membrane transport vesicles secreted by cells. EVs can take macromolecules from cells and transfer them to receptor cells. Among these macromolecular substances, the most studied are microRNAs (miRNAs). miRNA is non-coding RNA involved in the regulation of gene expression. It has been confirmed that there are different non-coding RNAs in mammalian follicular fluid EVs. EVs carrying miRNA can act as an alternative mechanism for autocrine and paracrine, affecting follicular development. This paper systematically introduced the kinds, characteristics and methods of isolation and identification of EVs, focusing on the effects of EVs and miRNAs on follicular development, including early follicular development, oocyte maturation, follicular dominance and effects on granulosa cell function. At the same time, the authors prospected the future research of EVs and microRNAs in follicular fluid, and provided ideas and directions for the research and application of EVs and miRNA functions in follicular fluid.


Assuntos
Vesículas Extracelulares , Líquido Folicular , MicroRNAs , Oogênese , Animais , Vesículas Extracelulares/metabolismo , Feminino , Líquido Folicular/química , Células da Granulosa/efeitos dos fármacos , MicroRNAs/farmacologia , Oogênese/efeitos dos fármacos
2.
Chemosphere ; 249: 126182, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32078850

RESUMO

An adverse tendency induced by the environmental estrogens in female reproductive health is one serious problem worldwide. Diethylstilbestrol (DES), as a synthetic estrogen, is still used as an animal growth stimulant in terrestrial livestock and aquaculture illegally. It has been reported to negatively affect ovarian function and oogenesis. Nevertheless, the mechanism and toxicity of DES on oocyte meiotic maturation are largely unknown. Herein, we found that DES (40 µM) intervened in mouse oocyte maturation and first polar body extrusion (PBE) was decreased in vitro. Cell cycle analysis showed meiotic process was disturbed with oocytes arrested at metaphase I (MI) stage after DES exposure. Further study showed that DES exposure disrupted the spindle assembly and chromosome alignment, which then continuously provoke the spindle assemble checkpoint (SAC). We also observed that the acetylation levels of α-tubulin were dramatically increased in DES-treated oocytes. In addition, the dynamics of actin were also affected. Moreover, the distribution patterns of estrogen receptor α (ERα) were altered in DES-treated oocyte, as indicated by the significant signals accumulation in the spindle area. However, ERα inhibitor failed to rescue the defects of oocyte maturation caused by DES. Of note, the same phenomenon was observed in estrogen-treated oocytes. Collectively, we showed that DES exposure lead to the oocyte meiotic failure via impairing the spindle assembly and chromosome alignment. Our research is helpful to understand how environmental estrogen affects female germ cells and contribute to design the potential therapies to preserve fertility especially for occupational exposure.


Assuntos
Dietilestilbestrol/toxicidade , Estrogênios não Esteroides/toxicidade , Animais , Processos de Crescimento Celular , Cromossomos , Feminino , Pontos de Checagem da Fase M do Ciclo Celular , Meiose/efeitos dos fármacos , Metáfase , Camundongos , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Fuso Acromático , Testes de Toxicidade , Tubulina (Proteína)/metabolismo
3.
PLoS One ; 15(2): e0229391, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32092110

RESUMO

Our previous work documented significant advancements in steroid-induced progression of oogenesis, demonstrating that co-treatment of female eels with 11-ketotestosterone (11KT) and estradiol-17ß (E2) successfully induced uptake of vitellogenin by oocytes. Here we evaluate the effects of this steroid co-treatment on subsequent time to ovulation and egg quality in shortfinned eels artificially matured by hypophysation. Co-treatment with 11KT (1 mg) and E2 (0.2 or 2 mg) significantly reduced time to ovulation and therefore, the amount of pituitary homogenate required, without any detrimental effects on gonadosomatic index, oocyte diameter or the total weight of stripped eggs. E2 treatment resulted in promising increases in fertilization rates. These indicators suggest that co-treatment with 11KT and E2 holds promise for future artificial maturation practices in terms of minimising fish handling and stress, and of reducing the need for expensive pituitary preparations.


Assuntos
Anguilla , Estradiol/farmacologia , Oogênese/efeitos dos fármacos , Indução da Ovulação , Testosterona/análogos & derivados , Anguilla/fisiologia , Animais , Feminino , Fertilidade/efeitos dos fármacos , Oócitos/citologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oogênese/fisiologia , Ovário/citologia , Ovário/efeitos dos fármacos , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Testosterona/farmacologia
4.
Environ Toxicol ; 35(2): 152-158, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696613

RESUMO

Fluorene-9-bisphenol (9,9-bis(4-hydroxyphenyl)-fluorene [BHPF]) is a bisphenol A (BPA) substitute used in the production of "BPA-free" plastics, now has been identified is harmful to living organisms. Our previous study showed that BHPF impaired mouse denuded oocyte in vitro maturation. However, there is a question that whether BHPF is still able to affect oocyte maturation in the presence of dense cumulus cells. In the present study, we checked the toxic effects of BHPF on porcine oocyte maturation which is derived from COCs in vitro culture. Our results showed that BHPF (50 µM) inhibited the expansion of cumulus cells, led to a significant decrease in polar body extrusion (PBE). Importantly, BHPF resulted in abnormal spindle assembly, ATP level decrease, reactive oxygen species (ROS) accumulation and early apoptosis in porcine oocytes, which are all negative to oocyte maturation. Furthermore, BHPF also declined porcine oocyte quality by disturbing the cortical granules (CGs) distribution. In conclusion, our study showed that BHPF still inhibited oocyte maturation even in the presence of cumulus cells leading to abnormal spindle assembly, ATP decrease, increased ROS level, early apoptosis, and disturbed CGs distribution in porcine oocytes, and also indicates that BHPF has a wide range toxic effects on oocyte in different species.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Fenóis/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Feminino , Técnicas de Maturação in Vitro de Oócitos , Camundongos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oócitos/patologia , Suínos
5.
Gen Comp Endocrinol ; 286: 113303, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31654676

RESUMO

The importance of cyclic guanosine monophosphate (cGMP) signaling pathway in oocyte maturation has recently attracted much attention in vertebrates. Previously, using zebrafish as a model, we have revealed the role of cGMP and the action of cGMP protein kinase (PKG) in oocyte maturation. In the present study, the function of a cGMP specific phosphodiesterase (PDE5a) is further analyzed in oocyte maturation in zebrafish. Two distinct PDE5a coding genes (named PDE5aa and PDE5ab) were identified in zebrafish, and expressed in most adult tissues including ovary. Both pde5aa and pde5ab mRNA are predominantly expressed in the oocyte but not in follicular cells. Two commercial antibodies targeted to mammalian PDE5a and phosphorylated PDE5a were validated in zebrafish, and we found both antibodies can be used to detect PDE5ab and phosphorylated PDE5ab of zebrafish, respectively. Using both antibodies, we found PDE5ab is only expressed in the oocyte and the phosphorylation of PDE5ab in oocyte could be activated during oocyte maturation induced by human chronic gonadotropin. Intriguingly, we found that the oocyte maturation could be stimulated by treatment of either two different PDE5a inhibitors, sildenafil or tadalafil, and such effects could be completely blocked by a PKG inhibitor KT5823 and two gap junction blockers, respectively. All of these results clearly demonstrate the importance of PDE5a in maintaining the oocyte maturation of zebrafish. When compared with mammals, the functional model of PDE5a is different in zebrafish, suggesting the function of PDE5a might shift from the oocyte in fish to the granulosa cell in mammals during evolution.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Oogênese/efeitos dos fármacos , Animais , Feminino , Humanos , Peixe-Zebra/metabolismo
6.
Theriogenology ; 142: 222-228, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629307

RESUMO

Disruption of the communication between the oocyte and granulosa cells is one of the major causes of poor development of in vitro grown ovarian follicles and oocytes. The present study investigated the effect of two cAMP modulators, cilostamide and forskolin, on in vitro growth of isolated dog secondary follicles and enclosed oocytes, communication between the gamete and surrounding granulosa cells, expression of GJA1 and GDF9, as well as cAMP level. Secondary follicles were incubated with cilostamide or forskolin alone or a combination of 20 µM cilostamide +1 µM forskolin, and the diameter of the incubated follicles and enclosed oocytes assessed every 72 h. Gap junction activity, GJA1 and GDF9 expression and cAMP level were assessed on Days 6 and 12 and transzonal projection (TZP) density was evaluated on Day 12. Neither cilostamide nor forskolin alone enhanced in vitro growth of dog follicles and the enclosed oocytes (P > 0.05). However, these two cAMP modulators dose dependently sustained gap junction activity and stimulated cAMP production compared with the non-supplemented control. Cilostamide at the high dosage (20 µM) also upregulated GJA1 expression. The combination of cilostamide and forskolin supported oocyte growth during the first 9 days and upregulated GJA1 and GDF9 expression at Day 12 of in vitro culture. This combination treatment also sustained gap junction activity, cAMP production, and increased TZP function (calcein intensity: TZP density ratio). The findings indicated that a combination of cilostamide and forskolin supported growth and survival of oocytes enclosed within cultured follicles by sustaining cAMP production and gap junction activity.


Assuntos
Colforsina/farmacologia , Cães , Junções Comunicantes/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Quinolonas/farmacologia , Animais , Células Cultivadas , Feminino , Junções Comunicantes/metabolismo , Meiose/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo
7.
Theriogenology ; 142: 296-302, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31708194

RESUMO

Environmental stresses, such as heat stress (HS), have been shown to have diverse effects on the developmental competence of oocytes. The aim of this study was to determine the effect of exogenous conjugated linoleic acid (CLA) supplementation in maturation medium on bovine oocyte maturation and developmental competence under HS condition. Accordingly, cumulus-oocyte complexes (COCs) were cultured at 41 °C and 38.5 °C for the first and second 12 h of maturation in the presence of 0 (PC), 50 (CLA50-HS) and 100 (CLA100-HS) µM CLA. Also, a group of COCs were cultured at 38.5 °C for 24 h of maturation without CLA supplementation as negative control (NC). Nuclear maturation, level of intracellular glutathione (GSH), reactive oxygen species (ROS) content, cleavage and blastocyst rates as well as relative expression of BAX, and BCL2 genes in blastocysts were investigated. Our finding for the PC and NC groups revealed that HS decreased the percentage of MII oocytes, cleavage and blastocyst rates (P < 0.05). Moreover, HS lead to an increase in ROS levels and relative expression of BAX gene, decreased the intracellular content of GSH and relative expression of BCL2 gene (P < 0.05). However, the cleavage and blastocyst rates tended to increase in the CLA-supplemented groups compared to PC group (p < 0.10). Also, ROS and GSH levels in the matured oocytes decreased and increased in the CLA50-HS group compared to the PC group (P < 0.05), respectively. The ratio of expression levels of BAX to BCL2 genes was not different between the PC and CLA50-HS groups (P > 0.05). These findings suggest that HS has undesirable effects on the maturation competence of bovine oocyte and subsequent embryo development while administration of CLA can ameliorate some of adverse effects of HS.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Transtornos de Estresse por Calor/patologia , Técnicas de Maturação in Vitro de Oócitos/métodos , Ácidos Linoleicos Conjugados/farmacologia , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Animais , Bovinos , Células Cultivadas , Meios de Cultura/química , Meios de Cultura/farmacologia , Feminino , Fertilização In Vitro , Glutationa/metabolismo , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/patologia , Oócitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo
8.
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
9.
Theriogenology ; 142: 320-327, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31711691

RESUMO

To optimize the protocols for assisted reproductive techniques (ARTs) in collared peccary (Pecari tajacu Linnaeus, 1758), we evaluated various conditions for oocyte in vitro maturation (IVM) and chemical activation. Initially, we assessed the IVM rates, cumulus-oocyte complex (COC) quality, and oocyte morphometry in the absence or presence of epidermal growth factor (EGF). There was no difference between the COCs matured in absence or presence of EGF for the expansion of cumulus cells (97.6% ±â€¯1.2 vs. 100% ±â€¯0.0), presence of first polar body (65.9% ±â€¯1.2 vs. 70.5% ±â€¯1.8), nuclear status in second metaphase (62.5% ±â€¯11.6 vs. 68.4% ±â€¯4.9), cytoplasmic maturation (100.0% ±â€¯0.7 vs. 75.0% ±â€¯0.7), reactive oxygen species levels (0.5 ±â€¯0.2 vs. 0.3 ±â€¯0.1), and mitochondrial membrane potential (1.1 ±â€¯0.2 vs. 1.1 ± 0.1). However, the zona pellucida thickness of matured COCs was reduced in the presence of EGF. Thus, the EGF group was used for further experiments. The oocytes were artificially activated with ionomycin and four secondary activator combinations [6-dimethylaminopurine (6D), 6D and cytochalasin B (6D + CB), cycloheximide (CHX), and CHX and CB (CHX + CB)]. The effect of immature COCs based on cumulus cell layers and cytoplasm homogeneity (GI and GII or GIII COCs) on embryonic development and quality was evaluated. There was no difference in the cleavage rates among the groups of secondary activators. The cleavage rates of embryos derived from GI/GII and GIII COCs were greater than 72.2% and 25.0%, respectively. Moreover, treatment with CHX showed a reduction in the cleavage rate of embryos derived from GIII COCs when compared to the cleavage rate of embryos derived from GI/GII COCs (P < 0.05). Nevertheless, higher rates of blastocyst/total GI and GII COCs were observed in the 6D group (27.6% ± 0.3) compared to CHX group (6.9% ± 0.3). Additionally, only 6D treatment resulted in the production of embryos derived from GIII COCs (25.0% ± 0.2). The percentage of the ICM/total cell ratio was also greater in blastocysts derived from 6D (42.5% ± 19.0), 6D + CB (37.9% ± 21.9), and CHX + CB (43.8% ± 19.6) groups when compared to CHX (3.6% ± 0.1) group. Thus, the combination of ionomycin and 6D could produce collared peccary embryos by activation of both GI/GII COCs and GIII COCs. These optimized IVM conditions using EGF and chemical activation using ionomycin and 6D in collared peccaries form the first steps for establishing ARTs to conserve this species.


Assuntos
Adenina/análogos & derivados , Artiodáctilos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Ionomicina/farmacologia , Oócitos/efeitos dos fármacos , Partenogênese/efeitos dos fármacos , Adenina/farmacologia , Animais , Artiodáctilos/embriologia , Células Cultivadas , Células do Cúmulo/citologia , Células do Cúmulo/efeitos dos fármacos , Células do Cúmulo/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Transferência Nuclear/veterinária , Oócitos/citologia , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , Oogênese/fisiologia , Partenogênese/fisiologia
10.
Toxicol Ind Health ; 35(11-12): 714-725, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31818241

RESUMO

This study aimed to evaluate the mancozeb (MNZ) impact on oocyte maturation of first-generation mice pups as well as their fertilization rate, embryo development, and implantation along with the preventative effect of vitamins E and C. Pregnant mice were randomly divided into six groups: control, vehicle, and MNZ (500 mg/kg body weight (BW)), vitamin E (200 mg/kg BW), MNZ plus vitamin E, MNZ plus vitamin C (100 mg/kg BW), and MNZ plus two vitamins. All treatments were conducted by oral gavage every 2 days from the second day of gestation until the end of lactation. Vitamin treatment was initiated 30 min before receiving MNZ. After birth, first-generation mice pups were kept until adulthood (8-10 W). Adult female mice pups superovulated and then the collected oocytes were examined for nuclear maturity status. After in vitro fertilization of metaphase II oocytes with sperm of the first-generation male mice pups, fertilization rate and embryo development were evaluated over 24 h. Also, the fecundity rate and the number of implanted embryos in vivo were studied on the eighth day of pregnancy. MNZ exposure during embryo development and lactation significantly decreased the total number of collected oocytes, oocyte maturation, fertilization rate, implantation rate, fecundity rate, and embryo development compared with the control group in the first-generation pups. In contrast, vitamin treatments significantly increased these parameters compared to the MNZ group. Reduction in the quality of oocyte, the rate of fertilization, embryo implantation, and development following MNZ exposure could decrease female reproductive success, while coadministration of vitamins E and C could prevent these complications.


Assuntos
Ácido Ascórbico/farmacologia , Fungicidas Industriais/toxicidade , Maneb/toxicidade , Exposição Materna/efeitos adversos , Vitamina E/farmacologia , Zineb/toxicidade , Animais , Animais Recém-Nascidos , Antioxidantes/farmacologia , Implantação do Embrião , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilização/efeitos dos fármacos , Lactação/efeitos dos fármacos , Camundongos , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Oogênese/efeitos dos fármacos , Gravidez
11.
Nat Commun ; 10(1): 5719, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31844300

RESUMO

It is known that granulosa cells (GCs) mediate gonadotropin-induced oocyte meiosis resumption by releasing EGF-like factors in mammals, however, the detailed molecular mechanisms remain unclear. Here, we demonstrate that luteinizing hormone (LH) surge-induced histone deacetylase 3 (HDAC3) downregulation in GCs is essential for oocyte maturation. Before the LH surge, HDAC3 is highly expressed in GCs. Transcription factors, such as FOXO1, mediate recruitment of HDAC3 to the amphiregulin (Areg) promoter, which suppresses AREG expression. With the LH surge, decreased HDAC3 in GCs enables histone H3K14 acetylation and binding of the SP1 transcription factor to the Areg promoter to initiate AREG transcription and oocyte maturation. Conditional knockout of Hdac3 in granulosa cells in vivo or inhibition of HDAC3 activity in vitro promotes the maturation of oocytes independent of LH. Taking together, HDAC3 in GCs within ovarian follicles acts as a negative regulator of EGF-like growth factor expression before the LH surge.


Assuntos
Anfirregulina/genética , Regulação da Expressão Gênica no Desenvolvimento , Histona Desacetilases/metabolismo , Meiose/genética , Oócitos/crescimento & desenvolvimento , Oogênese/genética , Acetilação , Animais , Células Cultivadas , Feminino , Proteína Forkhead Box O1/metabolismo , Técnicas de Inativação de Genes , Células da Granulosa/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Histonas/metabolismo , Hormônio Luteinizante/metabolismo , Camundongos , Oogênese/efeitos dos fármacos , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , Fator de Transcrição Sp1/metabolismo
12.
J Insect Physiol ; 119: 103968, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31669583

RESUMO

Queen pheromones effect the reproductive division of labour, a defining feature of eusociality. Reproductive division of labour ensures that one, or a small number of, females are responsible for the majority of reproduction within a colony. Much work on the evolution and function of these pheromones has focussed on Queen Mandibular Pheromone (QMP) which is produced by the Western or European honeybee (Apis mellifera). QMP has phylogenetically broad effects, repressing reproduction in a variety of arthropods, including those distantly related to the honeybee such as the fruit fly Drosophila melanogaster. QMP is highly derived and has little chemical similarity to the majority of hymenopteran queen pheromones which are derived from cuticular hydrocarbons. This raises the question of whether the phylogenetically widespread repression of reproduction by QMP also occurs with more basal saturated hydrocarbon-based queen-pheromones. Using D. melanogaster we show that saturated hydrocarbons are incapable of repressing reproduction, unlike QMP. We also show no interaction between the four saturated hydrocarbons tested or between the saturated hydrocarbons and QMP, implying that there is no conservation in the mechanism of detection or action between these compounds. We propose that the phylogenetically broad reproductive repression seen in response to QMP is not a feature of all queen pheromones, but unique to QMP itself, which has implications for our understanding of how queen pheromones act and evolve.


Assuntos
Alcanos/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Feromônios/farmacologia , Reprodução/efeitos dos fármacos , Animais , Abelhas/química , Feminino , Oogênese/efeitos dos fármacos
13.
Environ Pollut ; 255(Pt 1): 113194, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520902

RESUMO

Heavy metal cadmium (Cd) is a widespread environmental contaminant with a potential toxicity that might adversely influence the health of experimental animals and humans. It has been known that Cd might accumulate in vertebrates for many years and thus leads to the hepatic and renal toxicity. Additionally, Cd concentration in the ovary increases with age and is highly related to the reproductive hazard. However, the underlying mechanisms regarding how Cd affects the female reproductive system especially the oocyte quality have not yet fully defined. Here, we reported that Cd exposure led to the defective nuclear maturation of oocytes via the impairment of cytoskeleton assembly, displaying the aberrant spindle organization, chromosome alignment and actin polymerization. In the meantime, Cd exposure caused the impaired cytoplasmic maturation by showing the disrupted dynamics of mitochondrial integrity and cortical granules, and thereby resulting in the compromised sperm binding ability and fertilization capacity of oocytes. More importantly, we found that glutathione (GSH) supplementation was able to recover the meiotic failure induced by Cd exposure through suppressing the excessive ROS level, DNA damage accumulation and apoptotic incidence. Taken together, our findings demonstrate that Cd exposure has the adverse effects on the oocyte meiotic maturation as well as subsequent fertilization, and provide a potential effective strategy to improve the quality of Cd-exposed oocytes.


Assuntos
Cádmio/toxicidade , Mitocôndrias/patologia , Oócitos/citologia , Oogênese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Citoesqueleto/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Feminino , Glutationa/metabolismo , Humanos , Masculino , Meiose/efeitos dos fármacos , Oócitos/patologia , Suínos
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.
Cryobiology ; 90: 54-62, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31446003

RESUMO

The purpose of this study was to determine whether the mitochondrial membrane potential, pro-apoptotic gene expression, and ubiquitylation status of zona pellucida proteins (ZP1, ZP2, and ZP3) of vitrified GV-stage mature oocytes could be protected by treatment with cholesterol-loaded methyl-ß-cyclodextrin (CLC) prior to vitrification. Porcine GV oocytes were treated with CLC prior to the vitrification process, and the effects on the mitochondrial membrane potential and ZP ubiquitylation status were determined by JC-1 single staining and western blot assays. We found that porcine GV-stage oocytes were treated with CLC at different concentrations (0.5, 5, and 10 mg/mL) prior to vitrification improved in vitro maturation of these oocytes (P < 0.05). The mitochondrial membrane potential of matured oocyte without vitrification or treated with 5 mg/mL CLC vitrification treatment was higher than that of the 0 mg/mL CLC group and other treatment groups (vitrified) (P < 0.05). The expression of Caspase 3, Caspase 8, and Caspase 9 genes in the high concentration CLC treatment groups (5 and 10 mg/mL) was significantly lower than that in the 0 (vitrified) mg/mL CLC group (P < 0.05). ZPs protein and ZP3 protein ubiquitylation were also higher in the non-vitrified controls, 5 and 10 mg/mL CLC-treated oocytes than in the 0 (vitrified) and 0.5 mg/mL vitrified groups (P < 0.05). Whereas the sperm-oocyte binding capacity was improved in the CLC treatment groups (P < 0.05) but the embryonic development rate was not improved. In conclusion, pretreatment with CLC can improve the survival rate and maturation rate of oocytes and protect their mitochondria and zona pellucida of porcine oocytes from cryodamage during the vitrification process.


Assuntos
Colesterol/farmacologia , Crioprotetores/farmacologia , Oócitos/crescimento & desenvolvimento , Oogênese/efeitos dos fármacos , Glicoproteínas da Zona Pelúcida/metabolismo , beta-Ciclodextrinas/farmacologia , Animais , Caspase 3/biossíntese , Caspase 8/biossíntese , Caspase 9/biossíntese , Criopreservação/métodos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/fisiologia , Gravidez , Espermatozoides , Suínos , Ubiquitinação/efeitos dos fármacos , Vitrificação/efeitos dos fármacos , Zona Pelúcida/metabolismo
16.
Mar Biotechnol (NY) ; 21(5): 697-706, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372794

RESUMO

The availability of sexually mature fish often dictates the success of its captive breeding. In this study, we induced reproductive development in juvenile protogynous tiger grouper through oral administration of a plasmid (p) containing an engineered follicle-stimulating hormone (FSH). An expression construct (pcDNA3.1) was designed to express a single-chain FSH consisting of giant grouper FSH ß-subunit and glycoprotein subunit-α (CGα), linked by the carboxy-terminal peptide (CTP) sequence from the human chorionic gonadotropin (hCG). Single oral delivery of pFSH encapsulated in liposome and chitosan to tiger grouper yielded a significant increase in plasma FSH protein level after 4 days. Weekly pFSH feeding of juvenile tiger groupers for 8 weeks stimulated ovarian development as indicated by a significant increase in oocyte diameter and progression of oocytes to cortical alveolar stage. As the pFSH treatment progressed from 20 to 38 weeks, female to male sex change was initiated, characterized by oocyte regression, proliferation of spermatogonial cells, and occurrence of spermatogenic cysts. It was also associated with significantly lower mRNA expression of steroidogenic genes (cyp11b, cyp19a1a, and foxl2) and basal plasma levels of sex steroid hormones 17ß-estradiol (E2), testosterone (T), and 11-ketotestosterone (11KT). Results suggest that pFSH stimulates ovarian development up to cortical alveolar stage and then initiates sex change in tiger grouper. These findings significantly contribute to our knowledge on the role of FSH in the development of protogynous hermaphroditic fish. This study is the first to demonstrate induction of reproductive development in fish through oral delivery of plasmid gonadotropin.


Assuntos
Gonadotropina Coriônica/genética , Hormônio Foliculoestimulante/genética , Gônadas/efeitos dos fármacos , Organismos Hermafroditas/efeitos dos fármacos , Perciformes/genética , Processos de Determinação Sexual/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Administração Oral , Animais , Quitosana/química , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/biossíntese , Composição de Medicamentos , Feminino , Proteínas de Peixes/biossíntese , Proteínas de Peixes/genética , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/biossíntese , Hormônios Esteroides Gonadais/biossíntese , Hormônios Esteroides Gonadais/genética , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Organismos Hermafroditas/genética , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Masculino , Oogênese/efeitos dos fármacos , Oogênese/genética , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Pré-Seleção do Sexo/métodos , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética
17.
Chemosphere ; 237: 124435, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31352102

RESUMO

Glyphosate is a high-efficiency, low-toxicity, broad-spectrum herbicide. The residues of glyphosate-based herbicides are frequent pollutants in the environment. However, the effects of glyphosate on oocyte maturation, as well as its possible mechanisms, remain unclear. The present study revealed that mouse oocytes had reduced rates of germinal vesicle breakdown (GVBD) and first polar body extrusion (PBE) after treatment with 500 µM glyphosate. Reactive oxygen species (ROS) were found in mouse oocytes exposed to glyphosate, as shown by changes in the mRNA expression of related antioxidant enzyme genes (cat, sod2, gpx). After 14 h of exposure to glyphosate, metaphase II (MII) mouse oocytes displayed an abnormal spindle morphology and DNA double-strand breaks (DNA-DSBs). Simultaneously, mitochondria showed an aggregated distribution and decreased membrane potential in mouse oocytes exposed to glyphosate. The protein expression levels of apoptosis factors (Bax, Bcl-2) and the mRNA expression levels of apoptosis-related genes (bax, bcl-2, caspase3) were measured by Western blot and qRT-PCR, respectively. Meanwhile, the expression levels of autophagy-related genes (lc3, atg14, mtor) and proteins (LC3, Atg12) were significantly decreased in the glyphosate treatment group compared with the control group. Collectively, our results indicated that glyphosate exposure could interfere with mouse oocyte maturation by generating oxidative stress and early apoptosis.


Assuntos
Glicina/análogos & derivados , Oócitos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Feminino , Glicina/toxicidade , Herbicidas/toxicidade , Camundongos , Mitocôndrias/metabolismo , Oogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
18.
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
19.
Gen Comp Endocrinol ; 281: 83-90, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31170402

RESUMO

The function of insulin-like growth factor (Igf) system in ovary has attracted much attention, but the role of Igf binding proteins (Igfbps) in ovary is still largely unknown. In this study, the role of Igfbps in oocyte maturation was investigated in zebrafish. The expression of all eight identified Igfbps except Igfbp6b could be detected in the adult ovary and exhibited differential expression profiles during folliculogenesis. The expression of several Igfbps is dynamically changed during oocyte maturation induced by human chorionic gonadotropin (hCG). By treatment of an Igfbps inhibitor NBI-31772 in vitro, the oocyte maturation could be stimulated in a clear dose-, time- and stage-dependent manner. Such effects were also observed by administration of NBI-31772 in vivo. Igfbps are differentially expressed in both follicular cells and oocytes, but the effect of NBI-31772 could only be found in intact follicles and not in the denuded oocytes. Previous studies have demonstrated that Igf3 is the major Igf member in regulating oocyte maturation of zebrafish. Interestingly, NBI-31772 could increase the effect of Igf3 on oocyte maturation. Furthermore, we found the effect of NBI-31772 on oocyte maturation could be blocked by an Igf type 1 receptor inhibitor BMS-536924 in vitro, suggesting the Igfbps can inhibit the oocyte maturation via Igf/Igf1r pathway. Together, we provided the first evidence in fish that Igfbps inhibit oocyte maturation of zebrafish.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Oócitos/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Catecóis/farmacologia , Gonadotropina Coriônica/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/metabolismo , Isoquinolinas/farmacologia , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Zygote ; 27(3): 180-186, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31171044

RESUMO

SummaryHeat shock may disrupt oocyte function by increasing the generation of reactive oxygen species (ROS). We evaluated the capacity of the antioxidant melatonin to protect oocytes using two models of oxidative stress - heat shock and the pro-oxidant menadione. Bovine cumulus-oocyte complexes (COC) were exposed in the presence or absence of 1 µM melatonin to the following treatments during maturation: 38.5°C, 41°C and 38.5°C+5 µM menadione. In the first experiment, COC were matured for 3 h with 5 µM CellROX® and analyzed by epifluorescence microscopy to quantify production of ROS. The intensity of ROS was greater for oocytes exposed to heat shock and menadione than for control oocytes. Melatonin reduced ROS intensity for heat-shocked oocytes and oocytes exposed to menadione, but not for control oocytes. In the second experiment, COC were matured for 22 h. After maturation, oocytes were fertilized and the embryos cultured for 7.5 days. The proportion of oocytes that cleaved after fertilization was lower for oocytes exposed to heat shock and menadione than for control oocytes. Melatonin increased cleavage for heat-shocked oocytes and oocytes exposed to menadione, but not for control oocytes. Melatonin tended to increase the developmental competence of embryos from heat-shocked oocytes but not for embryos from oocytes exposed to menadione or from control oocytes. In conclusion, melatonin reduced production of ROS of maturing oocytes and protected oocytes from deleterious effects of both stresses on competence of the oocyte to cleave after coincubation with sperm. These results suggest that excessive production of ROS compromises oocyte function.


Assuntos
Resposta ao Choque Térmico , Melatonina/farmacologia , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Bovinos , Feminino , Técnicas de Maturação in Vitro de Oócitos , Microscopia de Fluorescência , Oócitos/citologia , Oócitos/metabolismo
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