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1.
Results Probl Cell Differ ; 68: 217-230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598858

RESUMO

Creophilus maxillosus (Staphylinidae, Coleoptera, Polyphaga) has a meroistic-telotrophic ovary composed of tropharium, which contains trophocytes (nurse cells) and vitellarium, which contains growing oocytes. The trophocytes are connected to the oocytes by cytoplasmic nutritive cords, which deliver nutrients to the oocytes. The formation/differentiation of the oocytes and trophocytes takes place in the pupal ovary within linear chains of sibling cells. Each chain is composed of a single oocyte connected to a linear chain of sister trophocytes. The nuclei of the oocytes contain an extrachromosomal DNA body (extra DNA body) consisting of amplified ribosomal DNA (rDNA). During oogenesis, the prospective oocyte, located at the base (posterior) of each chain, is the only cell within the chain that amplifies rDNA and retains permanent contact with the somatic pre-follicular cells. The oogonial divisions leading to the formation of the oocyte/trophocytes chain are asymmetric, and during consecutive divisions, the rDNA body always segregates basally (posteriorly) to the prospective oocyte abutted on the somatic cells. However, the segregation of rDNA is imperfect, and within each oocyte/trophocytes chain, there is a gradient of rDNA: the prospective oocyte has the highest amount of rDNA and the trophocyte that is most distant (most anterior) from the oocyte has no or the lowest amount of rDNA. In addition, the divisions within each chain are parasynchronous, with the pro-oocyte being the most mitotically advanced cell in the chain. These observations indicate the presence of a signaling gradient emanating from the somatic cells and/or oocyte; this gradient diminishes in strength with the increasing distance from its source, i.e., the oocyte/somatic cells. Because of this phenomenon, C. maxillosus is the perfect model in which to study the germ-somatic cell interactions and signaling. This chapter describes the methods for the collection and laboratory culture of C. maxillosus and the analysis of divisions and signaling in the C. maxillosus ovary.


Assuntos
Diferenciação Celular , Divisão Celular , Besouros/citologia , Modelos Animais , Oócitos/citologia , Transdução de Sinais , Animais , Feminino , Ovário/citologia
2.
Results Probl Cell Differ ; 68: 495-513, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598869

RESUMO

Even though tardigrades have been known since 1772, their phylogenetic position is still controversial. Tardigrades are regarded as either the sister group of arthropods, onychophorans, or onychophorans plus arthropods. Furthermore, the knowledge about their gametogenesis, especially oogenesis, is still poor and needs further analysis. The process of oogenesis has been studied solely for several eutardigradan species. Moreover, the spatial organization of the female germ-line clusters has been described for three species only. Meroistic ovaries characterize all analyzed species. In species of the Parachela, one cell per germ-cell cluster differentiates into the oocyte, while the remaining cells become the trophocytes. In Apochela several cells in the cluster differentiate into oocytes. Vitellogenesis is of a mixed type. The eggs are covered with the egg capsule that is composed of two shells: the thin vitelline envelope that adheres to the oolemma and the thick three-layered chorion. Chorion is formed as a first followed by vitelline envelope. Several features related to the oogenesis and structure of the ovary confirm the hypothesis that tardigrades are the sister group rather for arthropods than for onychophorans.


Assuntos
Oócitos/citologia , Oogênese , Ovário/anatomia & histologia , Tardígrados/anatomia & histologia , Tardígrados/fisiologia , Animais , Feminino , Ovário/citologia , Filogenia , Tardígrados/classificação
3.
Results Probl Cell Differ ; 68: 515-551, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598870

RESUMO

Animal female and male germ-line cells often form syncytial units termed cysts, clusters, or clones. Within these cysts, the cells remain interconnected by specific cell junctions known as intercellular bridges or ring canals, which enable cytoplasm to be shared and macromolecules and organelles to be exchanged between cells. Numerous analyses have shown that the spatial organization of cysts and their functioning may differ between the sexes and taxa. The vast majority of our knowledge about the formation and functioning of germ-line cysts comes from studies of model species (mainly Drosophila melanogaster); the other systems of the cyst organization and functioning are much less known and are sometimes overlooked. Here, we present the current state of the knowledge of female germ-line cysts in clitellate annelids (Clitellata), which is a monophyletic taxon of segmented worms (Annelida). The organization of germ-line cysts in clitellates differs markedly from that of the fruit fly and vertebrates. In Clitellata, germ cells are not directly connected one to another, but, as a rule, each cell has one ring canal that connects it to an anuclear central cytoplasmic core, a cytophore. Thus, this pattern of cell distribution is similar to the germ-line cysts of Caenorhabditis elegans. The last decade of studies has revealed that although clitellate female germ-line cysts have a strong morphological plasticity, e.g., cysts may contain from 16 to as many as 2500 cells, the oogenesis always shows a meroistic mode, i.e., the interconnected cells take on different fates; a few (sometimes only one) become oocytes, whereas the rest play the role of supporting (nurse) cells and do not continue oogenesis.This is the first comprehensive summary of the current knowledge on the organization and functioning of female germ-line cysts in clitellate annelids.


Assuntos
Anelídeos/citologia , Células Germinativas/citologia , Células Gigantes/citologia , Células Gigantes/fisiologia , Animais , Feminino , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Oogênese
4.
Life Sci ; 235: 116810, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472147

RESUMO

AIMS: Previous reports have demonstrated that melatonin exists in multiple extrapineal sites, and higher amounts of melatonin are present in human follicular fluid than in serum, which indicates that it might play key roles in human oocyte maturation and subsequent embryonic development. Melatonin has been shown to be a potent antioxidant and might be beneficial to human oocytes during in vitro maturation (IVM). However, the underlying mechanisms of melatonin action during IVM have not been thoroughly investigated. MAIN METHODS: Immunofluorescence staining, western blotting, and ELISA were applied to investigate whether melatoninergic components are expressed in the cultured human ovarian cumulus cells. TMRE staining and Fluo-4 AM staining were performed to detect the mitochondrial membrane potential and intracellular Ca2+ levels of immature human oocytes respectively. KEY FINDINGS: First, cultured human ovary cumulus cells synthesized melatonin in vitro, and it expressed serotonin (the precursor of melatonin) and the two key enzymes, i.e. N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT). Additionally, the results suggest that melatonin maintains the mitochondrial membrane potential and decrease excessive Ca2+ levels in immature human oocytes during IVM. SIGNIFICANCE: In conclusion, we provide evidence that the melatoninergic components were expressed in cultured human ovarian cumulus cells, and melatonin might reduce oxidative stress of human oocytes by ameliorating mitochondrial function. In view of the significant clinical value that immature human oocytes have in assisted reproductive technology (ART), our findings highlight a potential treatment strategy of using melatonin to improve mitochondrial function and to enhance the quality of human oocytes during IVM.


Assuntos
Antioxidantes/farmacologia , Cálcio/metabolismo , Melatonina/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Antioxidantes/análise , Feminino , Humanos , Técnicas de Maturação in Vitro de Oócitos , Melatonina/análise , Mitocôndrias/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Estresse Oxidativo
5.
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
6.
Adv Exp Med Biol ; 1155: 197-203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468398

RESUMO

It is well known that a large quantity of taurine is present in mammalian ovaries. Taurine reportedly promotes the secretion of female reproductive hormones by stimulating hypothalamus-pituitary-gonadal axis function. Therefore, we speculated that taurine may have beneficial effects on follicle growth, oocyte maturation, fertilization and cleavage. Here, we cultured rat follicles, immature oocytes and sperms in vitro and treated with taurine to observe the changes in follicle diameter, estradiol concentration as well as the rate of oocytes maturation, fertilization and cleavage using an inverted microscope. The results showed that taurine can elevate ovarian follicles growth and oocyte maturation, fertilization, and cleavage rates in vitro, which may be attributed to its osmoregulation and stimulation on the estradiol secretion. Our results provide important insights into taurine application in female production, although the underlying mechanism need to be further addressed.


Assuntos
Oócitos/citologia , Folículo Ovariano/efeitos dos fármacos , Taurina/farmacologia , Animais , Células Cultivadas , Estradiol , Feminino , Ratos
7.
Cryo Letters ; 40(4): 226-230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31278403

RESUMO

BACKGROUND: Vitrification by Rapid-I method could be essential for felid rescue programs to protect wild felid in the future. OBJECTIVE: This study was aimed at adapting the Rapid I method and evaluating the viability of serval and Pallas cat oocytes compared to oocytes of the domestic cat. MATERIALS AND METHODS: Oocytes after collection and in vitro maturation were vitrified using Cryotech medium (Cryotech, Japan) and a Rapid-I device (Vitrolife, Sweden). To evaluate viability, oocytes after warming were stained with fluorescein diacetate and ethidium bromide. RESULTS: Survival rate in the control group (domestic cat) was 75 %. In the experimental group, 70% (serval) and 60% (pallas cat) viable oocytes were found. CONCLUSION: The Rapid-I method can be applied successfully for the vitrification of wild felid oocytes.


Assuntos
Sobrevivência Celular , Criopreservação/veterinária , Felidae , Felis , Oócitos/citologia , Animais , Criopreservação/métodos , Crioprotetores , Feminino , Vitrificação
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(3): 419-424, 2019 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-31282340

RESUMO

The chromosomal aneuploidy in oocytes is one of main causes of abortion and neonatal birth defects.It is mainly due to the premature separation of sister chromatid caused by the loss of Cohesin protein complex and the non-disjunction sister chromatids caused by abnormal microtubule dynamics aneuploidy.As a pathway of protein post-translational modification,SUMO modification(or SUMOylation)involves many physiological regulation processes including cell proliferation,differentiation,apoptosis,and cycle regulation.In the oocytes,SUMOylation can regulate the localization of Cohesin protein complex on the chromosome to affect the chromosomal aneuploidy in oocytes caused by premature separation of sister chromatid.On the other hand,SUMOylation can regulate the microtubule dynamics to affect the chromosomal aneuploidy in oocytes caused by non-disjunction sister chromatids.Therefore,SUMOylation plays an important role in regulating the chromosomal aneuploidy of oocytes;the exact mechanisms via which the SUMOylated substrates affect aneuploidy in oocytes remain unclear.This articles reviews the roles of SUMOylation in premature separation and non-isolated chromatid aneuploidy in oocyte from the effects of SUMOylationon Cohesin protein complex and microtubule dynamics.


Assuntos
Aneuploidia , Cromátides , Segregação de Cromossomos , Oócitos/citologia , Sumoilação , Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona , Humanos , Microtúbulos
9.
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
10.
Eur Biophys J ; 48(6): 585-592, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31230258

RESUMO

In assisted reproduction technologies, the cryopreservation of oocytes is a common procedure used to circumvent female infertility. However, some morphological and functional alterations of oocytes have been observed depending on the protocol applied. In this work, the mechanical response of individual human oocytes before and after a freeze-thawing procedure was characterised. Oocytes, immediately after retrieval, were morphologically evaluated by bright-field optical microscopy and their elasticity measured by indentation measurements using atomic force microscopy. Oocytes were then frozen according to the open-vitrification protocol and stored in liquid nitrogen. Afterwards, the same oocytes were thawed and the indentation measurements repeated. Using this approach, we can follow the elasticity of a set of single oocytes from retrieval up to the freeze-thawing procedure. The analysis of the resulting data shows that the retrieved healthy oocytes, which preserve their healthy morphological features after cryopreservation, maintain unchanged also in stiffness values. In contrast, oocytes having dysmorphic characteristics, before and/or after freeze-thawing, show significant variations in their mechanical response. In addition, the dysmorphic oocytes are generally observed to be softer than the healthy oocytes. Our results indicate that stiffness of healthy oocytes is not considerably affected by the open-vitrification-thawing procedure, and that distinct elasticity ranges can be identified for healthy and dysmorphic oocytes. These findings indicate that the mechanical characterization of oocytes represents an opportunity to detect cellular defects, and assess the quality and bio-viability of processes such as cryopreservation.


Assuntos
Criopreservação , Fenômenos Mecânicos , Oócitos/citologia , Fenômenos Biomecânicos , Humanos
11.
J Ovarian Res ; 12(1): 53, 2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176373

RESUMO

OBJECT: To explore the mechanisms of ovarian aging, we performed overall analysis on the age-related alterations of gene expression profiles in mouse germinal vesicle (GV) stage oocytes by means of single-cell RNA-sequencing method (scRNA-seq). METHODS: Two age groups (5-week-old and 32-week-old) female KM mice were used as young and old models. Subsequently, GV oocytes were collected for scRNA-seq. The bioinformatics was performed to analyze and compare the differences of gene expression profile between GV oocytes of young and old mice. RESULTS: The analysis of scRNA-seq data showed that there were 624 differential expressed genes (DEGs) between two age groups of mouse GV stage oocytes. Four hundred forty-nine DEGs were up-regulated while 175 DEGs were down-regulated in the GV oocytes of the old group. KEGG pathway analysis revealed that the genes involved in mitochondrial function including oxidative phosphorylation and ATP production pathway were significantly down-regulated in GV oocytes of 32-week-old mice, especially the mitochondrial encoded NADH dehydrogenase (mt-Nd), including mt-Nd2, mt-Nd3, mt-Nd4, mt-Nd4L and mt-Nd5. Analysis of DEGs revealed that endoplasmic reticulum stress-related genes including AdipoR2, IRAK-1, RCAN1 and MsrB1 were significantly down-regulated in GV oocytes of 32-week-old mice. Also, analysis of DEGs demonstrated that anti-oxidation-related genes including Erbb3、Rcan1、Gsto2 and Msrb1 were significantly down-regulated in GV oocytes of old group. CONCLUSION: The disorder of mitochondrial function, endoplasmic reticulum stress and the reduced antioxidant capability might be involved in the progression of oocyte aging. Especially, the down regulation of mitochondrial encoded subunits of respiratory chain complexes might play critical roles in the relevant mechanisms.


Assuntos
Senescência Celular/genética , Estresse do Retículo Endoplasmático/genética , Mitocôndrias/genética , Oócitos/metabolismo , Envelhecimento , Animais , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Estresse Oxidativo/genética , Análise de Célula Única
12.
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
13.
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
14.
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
15.
Syst Parasitol ; 96(6): 521-526, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31089939

RESUMO

A new coccidian species (Chromista: Sporozoa: Eimeriidae) collected from the northern saw-whet owl Aegolius acadicus (Gmelin) is reported from Mexico. Eimeria aegoliusia n. sp. has subspherical oöcysts, with smooth, bi-layered wall. Micropyle and oöcyst residuum are both absent and a polar granule is present. To date, eight species of Eimeria Schneider, 1875 have been described from strigiform birds. Mean dimensions of sporulated oöcysts (23.7 × 22.4 µm) and sporocysts (12.8 × 8.3 µm) appear to be considerably smaller than those from other Eimeria spp. with owl definitive hosts: E. atheni Chauhan & Jain, 1979; E. megabubonis Upton, Campbell, Weigel & McKown, 1990; E. spenotytoi Carini, 1939; E. strigis Kutzer, 1963; and E. varia Upton, Campbell, Weigel & McKown. Dimensions of these sporulated oöcysts appear to be larger than those in E. bemricki Averbeck, Cooney, Guarnera, Redig & Stromberg, 1998. The presence of polar granules and their number allowed differentiation from E. bubonis Cawthorn & Stockdale, 1981 and E. nycteae Volf, Koudela & Modry, 1999. This is the first description of an eimeriid coccidian infecting A. acadicus.


Assuntos
Eimeria/classificação , Estrigiformes/parasitologia , Animais , Eimeria/citologia , México , Oócitos/citologia , Especificidade da Espécie
16.
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
17.
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
18.
Zygote ; 27(2): 97-100, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30871645

RESUMO

SummaryDifferent parameters affect the success of assisted reproduction technology (ART) treatments. One of the advantages of using intracytoplasmic sperm injection (ICSI) is that it also enables the assessment of the oocyte morphology. To date there has not been a clear conclusion on aberrant oocyte morphology and its consequences on the success of ART treatments. Therefore, in this study, we aimed to investigate the fertilization, embryo development and pregnancy rates in patients who have oocytes with granular cytoplasm. Additionally, we investigated if there were more aneuploid embryos obtained from abnormal cytoplasmic morphology. In total, 5704 oocytes were collected and, of these, 4036 were metaphase II (MII) oocytes. The morphology of these oocytes was assessed following denudation and 970 oocytes were observed to have granular cytoplasm. There was no difference in the fertilization rates between the oocytes with normal cytoplasm (89%) and oocytes with granular cytoplasm (72%). Cleavage of embryos and the number of embryos that reached the blastocyst stage were also similar in these two groups. The aneuploidy rates between the two groups were also similar. However, clinical pregnancies were significantly lower in embryos obtained from oocytes with granular cytoplasm (37.5% vs 70%, P<0.05). Therefore, the morphology of the oocyte is as important as morphology of the sperm. Even though normal fertilization and cleavage were achieved from oocytes with granular cytoplasm, their implantation potential was significantly compromised.


Assuntos
Oócitos/citologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Aneuploidia , Blastocisto/citologia , Blastocisto/fisiologia , Feminino , Humanos , Oócitos/fisiologia , Gravidez , Taxa de Gravidez , Diagnóstico Pré-Implantação
19.
Zygote ; 27(2): 55-63, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30871647

RESUMO

SummaryStudies have shown that daily exposure to different products, whether chemical or natural, can cause irreversible damage to women's reproductive health. Therefore it is necessary to use tests that evaluate the safety and efficacy of these products. Most reproductive toxicology tests are performed in vivo. However, in recent years, various cell culture methods, including embryonic stem cells and tissues have been developed with the aim of reducing the use of animals in toxicological tests. This is a major advance in the area of toxicology, as these systems have the potential to become a widely used tool compared with in vivo tests routinely used in reproductive biology and toxicology. The present review describes and highlights data on in vitro culture processes used to evaluate reproductive toxicity as an alternative to traditional methods using in vivo tests.


Assuntos
Técnicas de Cultura de Órgãos/métodos , Folículo Ovariano/citologia , Ovário/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Linhagem Celular , Feminino , Humanos , Oócitos/citologia , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovário/fisiologia
20.
Mol Biol (Mosk) ; 53(1): 3-15, 2019.
Artigo em Russo | MEDLINE | ID: mdl-30895948

RESUMO

This review analyzes three studies carried out on Drosophila, which resulted in discoveries that would be impossible while using other subjects. Thanks to these discoveries, events accompanying the myoblast fusion process, the oocyte polarization, and the functioning of supracellular linear actomyosin cable-like structures coordinating the polarization of the cytoskeleton of the cell can be described in detail.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster , Actomiosina/fisiologia , Animais , Fusão Celular , Citoesqueleto , Mioblastos/citologia , Oócitos/citologia
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