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1.
Cell Physiol Biochem ; 53(3): 439-452, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31436397

RESUMO

BACKGROUND/AIMS: Among the assisted reproductive techniques, the in vitro maturation of oocytes (IVM) is less developed than other techniques, but its implementation would entail a qualitative advance. This technique consists in the extraction of immature oocytes from antral ovarian follicles with the patient under low hormone stimulation or without hormone to mature exogenously in culture media supplemented with different molecules to promote maturation. In this sense, we are interested in the role that cannabinoids could have as IVM promoters because cannabinoid's molecular pathway is similar to the one by which oocyte's meiosis resumption is activated. With the intention of advancing in the possible use of cannabinoids as supplements for the media for in vitro maturation of oocytes, we intend to deepen the study of the function of the phytocannabinoid Δ-9-tetrahydrocannabinol (THC) in the IVM process. METHODS: By immunocytochemistry, we detected the location pattern of cannabinoid receptor type 1 (CB1) and type 2 (CB2) during oocyte maturation in presence or absence of THC, as well as, the staining pattern of p-AKT and p-ERK. We used a genetic/ pharmacological approach generating knockout oocytes for CB1 and/or CB2 and they were incubated with THC during the oocyte maturation to visualize the physiological effects of THC, observing the rate of blastocyst achieved by oocyte. RESULTS: This study confirms that the incubation of oocytes with THC during IVM accelerated some events of that process like the phosphorylation pattern of ERK and AKT and was able to increase the blastocyst rate in response to IVF. Moreover, it seems that both CB1 and CB2 are necessary to maintain a healthy oocyte maturation. CONCLUSION: Our data suggest that THC may be useful IVM supplements in clinic as is more feasible and reliable than any synthetic cannabinoid.


Assuntos
Blastocisto/efeitos dos fármacos , Dronabinol/farmacologia , Oócitos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Blastocisto/citologia , Blastocisto/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Fertilização In Vitro , Técnicas de Maturação in Vitro de Oócitos , Meiose/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oócitos/citologia , Oócitos/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo
2.
Nat Commun ; 10(1): 3053, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311924

RESUMO

The germline is the only cellular lineage capable of transferring genetic information from one generation to the next. Intergenerational transmission of epigenetic memory through the germline, in the form of DNA methylation, has been proposed; however, in mammals this is largely prevented by extensive epigenetic erasure during germline definition. Here we report that, unlike mammals, the continuously-defined 'preformed' germline of zebrafish does not undergo genome-wide erasure of DNA methylation during development. Our analysis also uncovers oocyte-specific germline amplification and demethylation of an 11.5-kb repeat region encoding 45S ribosomal RNA (fem-rDNA). The peak of fem-rDNA amplification coincides with the initial expansion of stage IB oocytes, the poly-nucleolar cell type responsible for zebrafish feminisation. Given that fem-rDNA overlaps with the only zebrafish locus identified thus far as sex-linked, we hypothesise fem-rDNA expansion could be intrinsic to sex determination in this species.


Assuntos
Metilação de DNA/fisiologia , DNA Ribossômico/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Oócitos/metabolismo , Peixe-Zebra/fisiologia , Animais , Desmetilação , Epigênese Genética/fisiologia , Feminino , Masculino , RNA Ribossômico/genética , Caracteres Sexuais
3.
Life Sci ; 232: 116639, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295472

RESUMO

AIMS: Sirtuins have been implicated in the aging process, however, the functions of SIRT2 in post-maturation aging of oocytes are not fully understood. The purpose of the present investigation was to assess the roles of SIRT2 in aged oocytes and mechanisms involved. MAIN METHODS: The fresh MII oocytes were aging in vitro, and treated with SIRT2 inhibitor (SirReal2), autophagy activator (Rapamycin), and autophagy inhibitor (3-Ma) for 24 h, respectively. Oocyte activation, cytoplasmic fragmentation, and spindle defects, mitochondrial distribution, ROS levels, ATP production, mitochondrial membrane potential, and early apoptosis were investigated. Western blotting was performed to determine LC3-II accumulation, SQSTM1 degradation, and caspase-3 activity. KEY FINDINGS: SIRT2 expression gradually decreased in a time-dependent manner during oocyte aging. Treatment with SirReal2 significantly increased the rates of oocyte activation, cytoplasmic fragmentation, and spindle defects. In particular, the high ROS levels, abnormal mitochondrial distribution, low ATP production, and lost ΔΨm were observed in SirReal2-exposed oocytes. Further analysis revealed that LC3-II accumulation and SQSTM1 degradation were induced by SIRT2 inhibition. By performing early apoptosis analysis showed that oocyte aging was accompanied with cellular apoptosis, and SIRT2 inhibition increased apoptosis rates of aged oocytes. Importantly, upregulating autophagy with Rapamycin could mimic the effects of SIRT2 inhibition on apoptosis by increasing caspase-3 activation, whereas downregulating autophagy with 3-MA could abolish those effects by blocking caspase-3 activation. SIGNIFICANCE: Our results suggest that SIRT2 inactivation is a key mechanism underlying of cellular aging, and SIRT2 inhibition contributes to autophagy-dependent cellular apoptosis in post-maturation oocytes.


Assuntos
Oócitos/fisiologia , Sirtuína 2/fisiologia , Acetamidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Bovinos , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Oócitos/classificação , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Sirolimo/farmacologia , Sirtuína 2/antagonistas & inibidores , Sirtuína 2/metabolismo , Tiazóis/farmacologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-31170475

RESUMO

Vitellogenin (Vtg) is a precursor protein of egg yolk proteins in oviparous and ovoviviparous vertebrates. Except in a case of exposure to estrogenic endocrine disruptors, Vtg is a female-specific protein and could be used as a molecular marker for sex identification. This would be especially useful in the case of the endangered European cave salamander Proteus anguinus in which sexes are indistinguishable according to external morphology, which hinders the establishment of a successful captive breeding program. Here we describe the identification, partial characterization, and purification of Vtg from P. anguinus. Vtg was identified in the plasma of a vitellogenic proteus female with visible oocytes. The identification of this protein was accomplished by mass spectrometry analysis. Two-dimensional gel electrophoresis revealed proteus Vtg as a mix of 190 kDa isoforms with isoelectric points in the pH range 5.3-6.0. Vtg was purified from proteus blood by gel filtration followed by anion-exchange chromatography. Using specific staining of SDS-PAGE gels, the Vtg was found to be phosphorylated and lipidated. Unlike the case in some other aquatic vertebrates, in P. anguinus, Vtg was not present in detectable amounts in cutaneous mucus. Degradation of oocytes in the captive vitellogenic female was accompanied by simultaneous decrease of Vtg concentration. Over a period of 10 months, the concentration of Vtg dropped from maximal to sub-detectable. Our results show that Vtg is a promising molecular marker for sex identification and ovary maturation in P. anguinus, which could contribute to the development of a viable program for captive reproduction of this unique species.


Assuntos
Proteidae/metabolismo , Análise para Determinação do Sexo/métodos , Vitelogeninas/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Cruzamento , Feminino , Oócitos/citologia , Oócitos/metabolismo , Proteidae/anatomia & histologia , Proteidae/genética , Eslovênia , Vitelogeninas/genética , Vitelogeninas/isolamento & purificação
5.
Ecotoxicol Environ Saf ; 181: 370-380, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31212185

RESUMO

Cigarette smoke can cause follicle destruction and oocyte dysfunction and increase the risks of spontaneous abortion, stillbirth, and tubal ectopic pregnancy, affecting female reproductive health. Third-hand smoke (THS) is residual tobacco smoke existing in the environment long after cigarettes are extinguished, which can react with other compounds in the environment to produce secondary pollutants. However, the effects of THS on the female reproductive system, particularly the maturation of the oocyte, remain unclear. 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal (NNA), a component of THS, is a logical biomarker of THS exposure. Thus, this study aims to investigate the toxic effects of NNA on the maturation of murine oocytes and subsequent developmental competence. Herein, murine oocytes were exposed to 0 (control group), 0.1, 1.0, 10, and 50 µM NNA for 24 h. Our results showed that NNA exposure reduced the polar body extrusion rate by causing 8-oxo-deoxyguanosine (8-OHdG) to increase and disrupting the meiotic spindle morphology by inhibiting ERK1/2 activation during in vitro maturation. Additionally, NNA exposure resulted in cleavage and blastocyst rate reduction by altering DNA and histone methylations by reducing 5 mC and H3K4me2 levels and by inducing apoptosis caused by mitochondrial dysfunction and reactive oxygen species accumulation, as shown by the increased superoxide dismutase mRNA level and by the decreased Bcl-x mRNA level. Collectively, our results demonstrate that NNA exposure reduces the maturation and developmental capability of murine oocytes by increasing the risk of DNA damage and abnormal spindle morphology, altering epigenetic modifications, and inducing apoptosis, suggesting the toxic effect of NNA on mammalian productive health.


Assuntos
Poluentes Ambientais/toxicidade , Nitrosaminas/toxicidade , Oócitos/efeitos dos fármacos , Animais , Apoptose , Dano ao DNA , Epigênese Genética , Feminino , Camundongos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fuso Acromático/efeitos dos fármacos
6.
Histochem Cell Biol ; 152(3): 207-215, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250100

RESUMO

Faithful chromosome segregation during the cell cycle is ensured by the spindle assembly checkpoint (SAC). Although SAC activity is highly conserved and most organisms share common SAC components, additional proteins that regulate SAC activity to ensure high fidelity chromosome segregation are present in higher eukaryotes. Zw10 is one of these additional SAC components. Although Zw10 has been demonstrated to be involved in SAC activity during mitosis, little is known about its role during oocyte meiosis. Here, we report that Zw10 is localized at the kinetochore and is required for SAC activation during meiotic maturation. Knockdown of Zw10 led to precocious polar body extrusion by impairing Mad2 recruitment at kinetochores. Moreover, Zw10 knockdown impaired chromosome alignment and kinetochore-microtubule attachment, increasing the incidence of aneuploidy. Furthermore, Zw10 expression decreased with maternal age, suggesting that Zw10 is associated with the age-related increase in the incidence of aneuploidy. Together, our results demonstrate that Zw10 is localized at kinetochores and functions as an essential SAC component in mouse oocytes.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular , Meiose , Oócitos/citologia , Oócitos/metabolismo , Animais , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Feminino , Pontos de Checagem da Fase M do Ciclo Celular/genética , Meiose/genética , Camundongos
7.
Parasit Vectors ; 12(1): 205, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060579

RESUMO

BACKGROUND: Vitellogenin (Vg), a key molecule for oocyte development synthesized in the fat body during blood-feeding, is released into the hemolymph and then taken into the oocytes via Vg receptor (VgR) in ticks. Previously, we showed that VgR mRNA is expressed in the ovary at the adult stage of parthenogenetic Haemaphysalis longicornis ticks and its expression increases after blood-feeding. However, intracellular localization of VgR mRNA and protein at each developmental stage of oocytes during oogenesis remains largely unclear. METHODS: mRNA and protein expression profiles of H. longicornis VgR (HlVgR) in the oocytes from the unfed to oviposition periods were analyzed by real-time PCR, in situ hybridization, and immunostaining. To elucidate the timing of the onset of Vg uptake, RNA interference (RNAi)-mediated gene silencing of HlVgR was performed. RESULTS: In situ hybridization revealed that HlVgR mRNA was detected in the cytoplasm of stage I-III oocytes, and weaker positive signals for HlVgR mRNA were found in the cell periphery of stage IV and V oocytes. Likewise, HlVgR protein was detected by immunostaining in the cytoplasm of stage I-III oocytes and in the cell periphery of stage IV and V oocytes. Each developmental stage of the oocytes showed distinct patterns of mRNA and protein expression of HlVgR. Moreover, RNAi of HlVgR caused delayed or arrested development in the oocytes. The ovaries of control ticks showed all developmental stages of oocytes, whereas stage I-III oocytes were found in the ovaries of HlVgR-RNAi ticks at 5 days after engorgement. CONCLUSIONS: These results suggest that active uptake of Vg is required for development from stage III to stage IV during oogenesis. Our data clearly revealed an apparent shift in the intracellular localization of VgR for both mRNA and protein level in oocytes during oogenesis.


Assuntos
Proteínas do Ovo/metabolismo , Ixodidae/metabolismo , Oogênese/fisiologia , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/metabolismo , Vitelogeninas/metabolismo , Animais , Proteínas do Ovo/genética , Feminino , Ixodidae/genética , Ixodidae/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oogênese/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Superfície Celular/genética , Transcriptoma
8.
Nat Genet ; 51(5): 844-856, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31040401

RESUMO

The oocyte epigenome plays critical roles in mammalian gametogenesis and embryogenesis. Yet, how it is established remains elusive. Here, we report that histone-lysine N-methyltransferase SETD2, an H3K36me3 methyltransferase, is a crucial regulator of the mouse oocyte epigenome. Deficiency in Setd2 leads to extensive alterations of the oocyte epigenome, including the loss of H3K36me3, failure in establishing the correct DNA methylome, invasion of H3K4me3 and H3K27me3 into former H3K36me3 territories and aberrant acquisition of H3K4me3 at imprinting control regions instead of DNA methylation. Importantly, maternal depletion of SETD2 results in oocyte maturation defects and subsequent one-cell arrest after fertilization. The preimplantation arrest is mainly due to a maternal cytosolic defect, since it can be largely rescued by normal oocyte cytosol. However, chromatin defects, including aberrant imprinting, persist in these embryos, leading to embryonic lethality after implantation. Thus, these data identify SETD2 as a crucial player in establishing the maternal epigenome that in turn controls embryonic development.


Assuntos
Desenvolvimento Embrionário/genética , Epigênese Genética , Impressão Genômica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Animais , DNA (Citosina-5-)-Metiltransferases/deficiência , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Feminino , Código das Histonas/genética , Histona-Lisina N-Metiltransferase/deficiência , Histonas/metabolismo , Masculino , Camundongos , Camundongos Knockout , Modelos Genéticos , Oócitos/metabolismo , Oogênese/genética , Gravidez
9.
Biomed Res Int ; 2019: 3842312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31058188

RESUMO

There are about 1-2 million follicles presented in the ovary at birth, while only around 1000 primordial follicles are left at menopause. The ovarian function also decreases in parallel with aging. Folliculogenesis is vital for ovarian function, no matter the synthesis of female hormones or ovulation, yet the mechanisms for its changing with increasing age are not fully understood. Early follicle growth up to the large preantral stage is independent of gonadotropins in rodents and relies on intraovarian factors. To further understand the age-related molecular changes in the process of folliculogenesis, we performed microarray gene expression profile analysis using total RNA extracted from young (9 weeks old) and old (32 weeks old) mouse ovarian secondary follicles. The results of our current microarray study revealed that there were 371 (≥2-fold, q-value ≤0.05) genes differentially expressed in which 174 genes were upregulated and 197 genes were downregulated in old mouse ovarian secondary follicles compared to young mouse ovarian secondary follicles. The gene ontology and KEGG pathway analysis of differentially expressed genes uncovered critical biological functions such as immune system process, aging, transcription, DNA replication, DNA repair, protein stabilization, and apoptotic process were affected in the process of aging. The considerable changes in gene expression profile may have an adverse influence on follicle quality and folliculogenesis. Our study provided information on the processes that may contribute to age-related decline in ovarian function.


Assuntos
Envelhecimento/genética , Folículo Ovariano/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , RNA/genética , Animais , Reparo do DNA/genética , Replicação do DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Menopausa/genética , Camundongos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Ovulação/genética , RNA/biossíntese , Transcriptoma/genética
10.
Cell Mol Life Sci ; 76(17): 3311-3322, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062072

RESUMO

Oxygen deprivation affects human health by modulating system as well as cellular physiology. Hypoxia generates reactive oxygen species (ROS), causes oxidative stress and affects female reproductive health by altering ovarian as well as oocyte physiology in mammals. Hypoxic conditions lead to several degenerative changes by inducing various cell death pathways like autophagy, apoptosis and necrosis in the follicle of mammalian ovary. The encircling somatic cell death interrupts supply of nutrients to the oocyte and nutrient deprivation may result in the generation of ROS. Increased level of ROS could induce granulosa cells as well as oocyte autophagy. Although autophagy removes damaged proteins and subcellular organelles to maintain the cell survival, irreparable damages could induce cell death within intra-follicular microenvironment. Hypoxia-induced autophagy is operated through 5' AMP activated protein kinase-mammalian target of rapamycin, endoplasmic reticulum stress/unfolded protein response and protein kinase C delta-c-junN terminal kinase 1 pathways in a wide variety of somatic cell types. Similar to somatic cells, we propose that hypoxia may induce granulosa cell as well as oocyte autophagy and it could be responsible at least in part for germ cell elimination from mammalian ovary. Hypoxia-mediated germ cell depletion may cause several reproductive impairments including early menopause in mammals.


Assuntos
Autofagia , Células da Granulosa/citologia , Animais , Proteína Beclina-1/metabolismo , Hipóxia Celular , Feminino , Células da Granulosa/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Planta Med ; 85(11-12): 925-933, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31127604

RESUMO

A fluorometric imaging plate reader (FLIPR) assay utilizing Chinese hamster ovary (CHO) cells stably transfected with GABAA receptors of α 1 ß 2 γ 2 subunit composition was evaluated and validated for rapid screening of plant extract libraries and efficient localization of active compounds in extracts. Validation was performed with pure compounds and extracts known to contain allosteric GABAA receptor modulators. Plants extracts that had been previously reported as active in an assay using Xenopus laevis oocytes transiently expressing GABAA receptors of α 1 ß 2 γ 2 subunit composition were also active in the FLIPR assay. A protocol for HPLC-based activity profiling was developed, whereby separations of 0.4 - 1.2 mg of extracts on an analytical HPLC column were found to be sufficient for the sensitivity of the bioassay. The protocol successfully localized the activity of known GABAergic natural products, such as magnolol in Magnolia officinalis, valerenic acid in Valeriana officinalis, and piperine in Piper nigrum extract. EC50 values of compounds (magnolol: 4.81 ± 1.0 µM, valerenic acid: 12.56 ± 1.2 µM, and piperine: 5.76 ± 0.7 µM) were found to be comparable or lower than those reported using Xenopus oocyte assays.


Assuntos
Fluorometria/métodos , Extratos Vegetais/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Alcaloides/farmacologia , Animais , Benzodioxóis/farmacologia , Bioensaio/métodos , Compostos de Bifenilo/farmacologia , Células CHO , Cromatografia Líquida de Alta Pressão , Cricetulus , Indenos/farmacologia , Lignanas/farmacologia , Magnolia/química , Oócitos/metabolismo , Piper nigrum/química , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Sesquiterpenos/farmacologia , Valeriana/química , Xenopus laevis
12.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067669

RESUMO

This paper aims to identify and describe new genetic markers involved in the processes of protein expression and modification reflected in the change of mitochondrial activity before and after in vitro maturation of the oocyte. Porcine oocytes collected from the ovaries of slaughtered landrace gilts were subjected to the process of in vitro maturation. Transcriptomic changes in the expression profile of oocyte genes involved in response to hypoxia, the transmembrane protein receptor serine threonine kinase signaling pathway, the "transforming growth factor ß receptor signaling pathway", "response to protein stimulus", and "response to organic substance" were investigated using microarrays. The expression values of these genes in oocytes was analyzed before (immature) and after (mature) in vitro maturation, with significant differences found. All the significantly altered genes showed downregulation after the maturation process. The most changed genes from these gene ontologies, FOS, ID2, VEGFA, BTG2, CYR61, ESR1, AR, TACR3, CCND2, CHRDL1, were chosen to be further validated, described and related to the literature. Additionally, the mitochondrial activity of the analyzed oocytes was measured using specific dyes. We found that the mitochondrial activity was higher before the maturation process. The analysis of these results and the available literature provides a novel insight on the processes that occur during in vitro oocyte maturation. While this knowledge may prove to be useful in further research of the procedures commonly associated with in vitro fertilization procedures, it serves mostly as a basic reference for further proteomic, in vivo, and clinical studies that are necessary to translate it into practical applications.


Assuntos
Mitocôndrias/metabolismo , Oócitos/metabolismo , Oogênese/genética , Transcriptoma , Animais , Hipóxia Celular/genética , Células Cultivadas , Feminino , Técnicas de Maturação in Vitro de Oócitos , Mitocôndrias/genética , Oócitos/citologia , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Suínos , Fator de Crescimento Transformador beta/metabolismo
13.
Mol Med Rep ; 19(6): 5353-5360, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059097

RESUMO

Ppm1b, a metal­dependent serine/threonine protein phosphatase, catalyzes the dephosphorylation of a variety of phosphorylated proteins. Ppm1b­/­ mouse embryos die at the fertilized oocyte stage, whereas Ppm1b+/­ mice with a C57BL/6 background exhibit no phenotypic abnormalities. Because the C57BL/6 strain produces a limited number of pups, in an attempt to produce Ppm1b­/­ mice, congenic Ppm1b+/­ mice with an ICR background were established, which are more fertile and gave birth to more pups. As a result, however, no Ppm1b­/­ offspring were obtained when pairs of Ppm1b+/­ ICR mice were bred again. Ppm1b+/­ male and female ICR mice were analyzed from the viewpoint of fecundity. The Ppm1b haploinsufficiency had no effect on testicular weight or the number of sperm in male mice. Despite the fact that the levels of Ppm1b protein in the ovaries of sexually mature Ppm1b+/­ mice were decreased compared with those of Ppm1b+/+ mice, there appeared to be no significant difference in the histological appearance of the ovaries, litter sizes or plasma progesterone levels at the estrous stage. When superovulation was induced by stimulation using a hormone treatment, the number of ovulated oocytes were the same for Ppm1b+/­ and Ppm1b+/+ mice at 4 weeks of age when the estrous cycle did not proceed, however, the number of ovulated oocytes was lower in sexually mature Ppm1b+/­ mice at 11 weeks of age compared with Ppm1b+/+ mice in the first and the second superovulation cycles. These collective results suggest that follicle development is excessive in Ppm1b+/­ mice, and that this leads to a partial depletion of matured follicles and a corresponding decrease in the number of ovulated oocytes.


Assuntos
Proteína Fosfatase 2C/genética , Superovulação , Animais , Gonadotropina Coriônica/farmacologia , Feminino , Heterozigoto , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Oócitos/citologia , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Ovário/metabolismo , Gravidez , Progesterona/sangue , Proteína Fosfatase 2C/metabolismo , Superovulação/efeitos dos fármacos
14.
Cell Mol Biol (Noisy-le-grand) ; 65(4): 83-89, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31078160

RESUMO

The follicle must fulfill the following criteria if it is to survive the period between early embryonic life and the luteinizing hormone (LH) peak. It should (i) be surrounded by pregranulosa cells; (ii) complete the first meiotic division and become dormant; and (iii) continue metabolism during the dormant stage. Interaction between the natriuretic peptide precursor type C (Nppc) and its receptor, natriuretic peptide receptor 2 (Npr2), affects female fertility through the production of oocytes with developmental capacity and maintain oocyte meiotic arrest. While Nppc is expressed in mural cells, cumulus cells express Npr2. Nppc/Npr2 system exerts its biological function on developing follicles by increasing the production of intracellular cyclic guanosine monophosphate (cGMP). This pathway not only contributes to the development of ovary and the uterus, but aids the formation of healthy eggs in terms of their morphological and genetic aspects. A defect in this pathway leads to asmall ovarian size, string-like uterine horns, and thin endometrium and myometrium. Disorganized chromosomes, abnormal cumulus expansion and early meiotic resumption occur in animals with defective Nppc/Npr2 signaling. The types and number of oocytes also decrease when there is incompetent Nppc/Npr2 signaling. This paper extends on most recent and relevant experimental evidence regarding Nppc/Npr2/cGMP signaling with regard to its crucial role in maintaining oocyte meiotic arrest and the production of oocytes with developmental capacity. We further discuss whether the agonist or antagonist forms of the members of this exciting pathway can be usedfor triggering final oocyte maturation.


Assuntos
GMP Cíclico/metabolismo , Peptídeo Natriurético Tipo C/metabolismo , Oócitos/metabolismo , Receptores do Fator Natriurético Atrial/metabolismo , Transdução de Sinais , Animais , Fertilização In Vitro , Humanos
15.
BMC Plant Biol ; 19(1): 190, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068146

RESUMO

BACKGROUND: The functional characteristics of SLAC/SLAH family members isolated from Arabidopsis thaliana, poplar, barley and rice have been comprehensively investigated. However, there are no reports regarding SLAC/SLAH family genes from Rosaceae plants. RESULTS: In this study, the function of PbrSLAH3, which is predominately expressed in pear (Pyrus bretschneideri) root, was investigated. PbrSLAH3 can rescue the ammonium toxicity phenomenon of slah3 mutant plants under high-ammonium/low-nitrate conditions. In addition, yeast two-hybrid and bimolecular fluorescence complementation assays confirmed that PbrSLAH3 interacts with PbrCPK32. Moreover, when PbrSLAH3 was co-expressed with either the Arabidopsis calcium-dependent protein kinase (CPK) 21 or PbrCPK32 in Xenopus oocytes, yellow fluorescence was emitted from the oocytes and typical anion currents were recorded in the presence of extracellular NO3-. However, when PbrSLAH3 alone was injected, no yellow fluorescence or anion currents were recorded, suggesting that anion channel PbrSLAH3 activity was controlled through phosphorylation. Finally, electrophysiological and transgene results showed that PbrSLAH3 was more permeable to NO3- than Cl-. CONCLUSION: We suggest that PbrSLAH3 crossing-talk with PbrCPK32 probably participate in transporting of nitrate nutrition in pear root.


Assuntos
Canais Iônicos/metabolismo , Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Pyrus/enzimologia , Compostos de Amônio/toxicidade , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Fenômenos Eletrofisiológicos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Mutação/genética , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Pyrus/efeitos dos fármacos , Pyrus/genética , Xenopus
16.
Ecotoxicol Environ Saf ; 180: 168-178, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31082581

RESUMO

Fluorene-9-bisphenol (BHPF), a substitute for bisphenol A, is a chemical component of plastics for industrial production. There is evidence that BHPF exerts an antioestrogenic effect on mice, induces endometrial atrophy and leads to adverse pregnancy outcomes. However, the effects of BHPF on oocyte maturation and ovary development as well as its possible mechanisms remain unclear. The objective of this study was to investigate the toxicity and mechanism of BHPF exposure in mouse oocytes in vitro and in vivo. Our results showed that BHPF could inhibit the maturation of oocytes in vitro by reducing the protein level of p-MAPK and destroying the meiotic spindle. We found that in vitro, BHPF-treated oocytes showed increased ROS levels, DNA damage, mitochondrial dysfunction, and expression of apoptosis- and autophagy-related genes, such as Bax, cleaved-caspase 3, LC 3 and Atg 12. In addition, in vivo experiments showed that BHPF exposure could induce the expression of oxidative stress genes (Cat, Gpx 3 and Sod 2) and apoptosis genes (Bax, Bcl-2 and Cleaved-caspase 3) and increase the number of atresia follicles in the ovaries. Our data showed that BHPF exposure affected the first polar body extrusion of oocytes, increased oxidative stress, destroyed spindle assembly, caused DNA damage, altered mitochondrial membrane potentials, induced apoptosis and autophagy, and affected ovarian development.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fluorenos/toxicidade , Oócitos/patologia , Ovário/patologia , Fenóis/toxicidade , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Estresse Oxidativo/efeitos dos fármacos
17.
Cell Mol Life Sci ; 76(11): 2217-2229, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980108

RESUMO

As the female gamete, meiotic oocytes provide not only half of the genome but also almost all stores for fertilization and early embryonic development. Because de novo mRNA transcription is absent in oocyte meiosis, protein-level regulations, especially the ubiquitin proteasome system, are more crucial. As the largest family of ubiquitin E3 ligases, Skp1-Cullin-F-box complexes recognize their substrates via F-box proteins with substrate-selected specificity. However, the variety of F-box proteins and their unknown substrates hinder our understanding of their functions. In this report, we find that Fbxo30, a new member of F-box proteins, is enriched in mouse oocytes, and its expression level declines substantially after the metaphase of the first meiosis (MI). Notably, depletion of Fbxo30 causes significant chromosome compaction accompanied by chromosome segregation failure and arrest at the MI stage, and this arrest is not caused by over-activation of spindle assembly checkpoint. Using immunoprecipitation and mass spectrometric analysis, we identify stem-loop-binding protein (SLBP) as a novel substrate of Fbxo30. SLBP overexpression caused by Fbxo30 depletion results in a remarkable overload of histone H3 on chromosomes that excessively condenses chromosomes and inhibits chromosome segregation. Our finding uncovers an unidentified pathway-controlling chromosome segregation and cell progress.


Assuntos
Segregação de Cromossomos , Cromossomos de Mamíferos/metabolismo , Proteínas F-Box/genética , Histonas/genética , Meiose , Proteínas Nucleares/genética , Oócitos/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/genética , Animais , Cromossomos de Mamíferos/ultraestrutura , Proteínas F-Box/antagonistas & inibidores , Proteínas F-Box/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteínas Nucleares/metabolismo , Oócitos/ultraestrutura , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
18.
mSphere ; 4(2)2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944211

RESUMO

Inorganic pyrophosphate (PPi) is a by-product of biosynthetic reactions and has bioenergetic and regulatory roles in a variety of cells. Here we show that PPi and other pyrophosphate-containing compounds, including polyphosphate (polyP), can stimulate sodium-dependent depolarization of the membrane potential and Pi conductance in Xenopus oocytes expressing a Saccharomyces cerevisiae or Trypanosoma brucei Na+/Pi symporter. PPi is not taken up by Xenopus oocytes, and deletion of the TbPho91 SPX domain abolished its depolarizing effect. PPi generated outward currents in Na+/Pi-loaded giant vacuoles prepared from wild-type or pho91Δ yeast strains expressing TbPHO91 but not from the pho91Δ strains. Our results suggest that PPi, at physiological concentrations, can function as a signaling molecule releasing Pi from S. cerevisiae vacuoles and T. brucei acidocalcisomes.IMPORTANCE Acidocalcisomes, first described in trypanosomes and known to be present in a variety of cells, have similarities with S. cerevisiae vacuoles in their structure and composition. Both organelles share a Na+/Pi symporter involved in Pi release to the cytosol, where it is needed for biosynthetic reactions. Here we show that PPi, at physiological cytosolic concentrations, stimulates the symporter expressed in either Xenopus oocytes or yeast vacuoles via its SPX domain, revealing a signaling role of this molecule.


Assuntos
Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato/metabolismo , Simportadores/genética , Trypanosoma brucei brucei/metabolismo , Vacúolos/metabolismo , Animais , Potenciais da Membrana , Oócitos/metabolismo , Fosfatos/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Sódio/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato/genética , Trypanosoma brucei brucei/genética , Xenopus/metabolismo
19.
Gen Comp Endocrinol ; 277: 122-129, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30951723

RESUMO

Gonadal soma-derived factor (Gsdf) is a unique TGF-ß factor essential for both ovarian and testicular development in Hd-rR medaka (Oryzias latipes). However, the downstream genes regulated by Gsdf signaling remain unknown. Using a high-throughput proteomic approach, we identified a significant increase in the expression of the RNA-binding protein Igf2bp3 in gsdf-deficient ovaries. We verified this difference in transcription and protein expression against normal gonads using real-time PCR quantification and Western blotting. The genomic structure of igf2bp3 and the syntenic flanking segments are highly conserved across fish and mammals. igf2bp3 expression was correlated with oocyte development, which is consistent with the expression of the igf2bp3 ortholog Vg1-RBP/Vera in Xenopus. In contrast to the normal ovary, cysts of H3K27me3- and Igf2bp3-positive germ cells were dramatically increased in the one-month-old gsdf-deficient ovary, indicating that the gsdf depletion led to a dysregulation of Igf2bp3-mediated oocyte development. Our results provide novel insights into the Gsdf-Igf2bp3 signaling mechanisms that underlie the fundamental process of gametogenesis; these mechanisms may be well conserved across phyla.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Oócitos/metabolismo , Oryzias/genética , Proteínas de Ligação a RNA/genética , Fator de Crescimento Transformador beta/deficiência , Sequência de Aminoácidos , Animais , Proliferação de Células , Sequência Conservada , Evolução Molecular , Feminino , Perfilação da Expressão Gênica , Histonas/metabolismo , Lisina/metabolismo , Masculino , Oogênese/genética , Ovário/embriologia , Ovário/metabolismo , Filogenia , Proteômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/metabolismo
20.
Anim Sci J ; 90(7): 840-848, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31006939

RESUMO

We report the cryopreservation of oocytes from Ban miniature pigs which are endemic in Vietnam. Immature cumulus-oocyte complexes were collected from antral follicles of 7-8 mo old female cyclic Ban pigs and vitrified in micro-drops. Oocyte morphology, lipid content, post-warming survival, nuclear maturation, and embryo development were compared to those of oocytes from commercially slaughtered Landrace × Large white hybrid pigs. The size of oocytes in the two breeds was similar. However, significantly lower amounts of intracellular lipid were detected in Ban oocytes. There was no difference (p > 0.05) between Ban and Landrace × Large white oocytes in percentages of post-warming survival (93.1 ± 3.4% vs. 70.7 ± 16.7%, respectively) and nuclear maturation after in vitro maturation (80.4 ± 5.1% vs. 90.0 ± 1.3% respectively). Similarly, cleavage (30.8 ± 7.8% vs. 10.3 ± 6.1%, respectively) and blastocyst development rates (9.4 ± 5.0% vs. 0.79 ± 0.79, respectively) were not different (p > 0.05) between vitrified Ban and Landrace × Large white oocytes after in vitro fertilization and embryo culture. In conclusion, high survival and maturation rates were achieved after vitrification of immature Ban oocytes and their cryo-tolerance was similar to that of Landrace × Large white oocytes, despite the difference in lipid content. We succeeded to generate reasonable rates of blastocysts from vitrified Ban oocytes by in vitro fertilization.


Assuntos
Criopreservação/métodos , Oócitos , Porco Miniatura , Preservação de Tecido/métodos , Animais , Blastocisto , Sobrevivência Celular , Células Cultivadas , Desenvolvimento Embrionário , Feminino , Fertilização In Vitro , Técnicas de Maturação in Vitro de Oócitos , Metabolismo dos Lipídeos , Oócitos/citologia , Oócitos/metabolismo , Oócitos/fisiologia , Manejo de Espécimes/métodos , Suínos
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