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Oocyte meiotic maturation failure and chromosome abnormality is one of the main causes of infertility, abortion, and diseases. The mono-orientation of sister chromatids during the first meiosis is important for ensuring accurate chromosome segregation in oocytes. MEIKIN is a germ cell-specific protein that can regulate the mono-orientation of sister chromatids and the protection of the centromeric cohesin complex during meiosis I. Here we found that MEIKIN is a maternal protein that was highly expressed in mouse oocytes before the metaphase I (MI) stage, but became degraded by the MII stage and dramatically reduced after fertilization. Strikingly, MEIKIN underwent phosphorylation modification after germinal vesicle breakdown (GVBD), indicating its possible function in subsequent cellular event regulation. We further showed that MEIKIN phosphorylation was mediated by PLK1 at its carboxyl terminal region and its C-terminus was its key functional domain. To clarify the biological significance of meikin degradation during later stages of oocyte maturation, exogenous expression of MEIKIN was employed, which showed that suppression of MEIKIN degradation resulted in chromosome misalignment, cyclin B1 and Securin degradation failure, and MI arrest through a spindle assembly checkpoint (SAC)-independent mechanism. Exogenous expression of MEIKIN also inhibited metaphase II (MII) exit and early embryo development. These results indicate that proper MEIKIN expression level and its C-terminal phosphorylation by PLK1 are critical for regulating the metaphase-anaphase transition in meiotic oocyte. The findings of this study are important for understanding the regulation of chromosome segregation and the prevention meiotic abnormality.
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BACKGROUND: Dual-person inspection in IVF laboratories cannot fully avoid mix-ups or embryo transfer errors, and data transcription or entry is time-consuming and redundant, often leading to delays in completing medical records. METHODS: This study introduced a workflow-based RFID tag witnessing and real-time information entry platform for addressing these challenges. To assess its potential in reducing mix-ups, we conducted a simulation experiment in semen preparation to analyze its error correction rate. Additionally, we evaluated its impact on work efficiency, specifically in operation and data entry. Furthermore, we compared the cycle costs between paper labels and RFID tags. Finally, we retrospectively analyzed clinical outcomes of 20,424 oocyte retrieval cycles and 15,785 frozen embryo transfer cycles, which were divided into paper label and RFID tag groups. RESULTS: The study revealed that comparing to paper labels, RFID tag witnessing corrected 100% of tag errors, didn't affect gamete/embryo operations, and notably shorten the time of entering data, but the cycle cost of RFID tags was significantly higher. However, no significant differences were observed in fertilization, embryo quality, blastocyst rates, clinical pregnancy, and live birth rates between two groups. CONCLUSIONS: RFID tag witnessing doesn't negatively impact gamete/embryo operation, embryo quality and pregnancy outcomes, but it potentially reduces the risk of mix-ups or errors. Despite highly increased cost, integrating RFID tag witnessing with real-time information entry can remarkably decrease the data entry time, substantially improving the work efficiency. This workflow-based management platform also enhances operational safety, ensures medical informational integrity, and boosts embryologist's confidence.
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Transferencia de Embrión , Fertilización In Vitro , Dispositivo de Identificación por Radiofrecuencia , Flujo de Trabajo , Humanos , Femenino , Fertilización In Vitro/métodos , Embarazo , Estudios Retrospectivos , Transferencia de Embrión/métodos , Dispositivo de Identificación por Radiofrecuencia/métodos , Laboratorios , Adulto , Masculino , Índice de Embarazo , Resultado del EmbarazoRESUMEN
BACKGROUND: Pulmonary embolisms (PEs) exhibit clinical features similar to those of acute coronary syndrome (ACS), including electrocardiographic abnormalities and elevated troponin levels, which frequently lead to misdiagnoses in emergency situations. CASE PRESENTATION: Here, we report a case of PE coinciding with chronic coronary syndrome in which the patient's condition was obscured by symptoms mimicking ACS. A 68-year-old female with syncope presented to the hospital. Upon admission, she was found to have elevated troponin levels and an electrocardiogram showing ST-segment changes across multiple leads, which initially led to a diagnosis of ACS. Emergency coronary arteriography revealed occlusion of the posterior branches of the left ventricle of the right coronary artery, but based on the complexity of the intervention, the occlusion was considered chronic rather than acute. On the 3rd day after admission, the patient experienced recurrent chest tightness and shortness of breath, which was confirmed as acute PE by emergency computed tomography pulmonary angiography. Following standardized anticoagulation treatment, the patient improved and was subsequently discharged. CONCLUSIONS: This case report highlights the importance of recognizing the nonspecific features of PE. Clinicians should be vigilant when identifying other clinical features that are difficult to explain accompanying the expected disease, and it is necessary to carefully identify the causes to prevent missed diagnoses or misdiagnoses.
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Síndrome Coronario Agudo , Anticoagulantes , Angiografía por Tomografía Computarizada , Electrocardiografía , Valor Predictivo de las Pruebas , Embolia Pulmonar , Humanos , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/diagnóstico por imagen , Femenino , Anciano , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/diagnóstico por imagen , Diagnóstico Diferencial , Anticoagulantes/uso terapéutico , Angiografía Coronaria , Enfermedad Crónica , Resultado del Tratamiento , Errores Diagnósticos , Biomarcadores/sangreRESUMEN
Introduction: Malnutrition is strongly associated with heart failure (HF); however, the causal link remains unclear. We used Mendelian randomization (MR) to infer causal associations between different nutritional assessment phenotypes and HF and to analyze whether these associations were mediated by common HF risk factors. Methods: Two-sample bidirectional MR was used to infer causal associations between nutritional assessment phenotypes and HF. Mutual influences between different nutritional assessment phenotypes and potential correlations were estimated using multivariate MR methods. Two-step MR was used to quantify the mediating effects of common HF risk factors on the causal associations. Results: Three phenotypes were positively associated with the development of HF: waist circumference (WC) (odds ratio [OR] = 1.74; 95% confidence interval [CI], 1.60-1.90; P = 3.95 × 10-39), body mass index (BMI) (OR = 1.70; 95%CI, 1.60-1.80; P = 1.35 × 10-73), and whole body fat mass (WBFM) (OR = 1.54; 95%CI, 1.44-1.65; P = 4.82 × 10-37). Multivariate MR indicated that WBFM remained positively associated with HF after conditioning on BMI and WC (OR = 2.05; 95%CI, 1.27-3.31; P = 0.003). Three phenotypes were negatively correlated with the development of HF: usual walking pace (UWP) (OR = 0.40; 95%CI, 0.27-0.60; P = 8.41 × 10-6), educational attainment (EA) (OR = 0.73; 95%CI, 0.67-0.79; P = 2.27 × 10-13), and total cholesterol (TC) (OR = 0.90; 95%CI, 0.84-0.96; P = 4.22 × 10-3). There was a bidirectional causality between HF and UWP (Effect estimate = -0.03; 95%CI, -0.05 to -0.01; P = 1.95 × 10-3). Mediation analysis showed that common risk factors for HF (hypertension, coronary artery disease, cardiomyopathy, and valvular heart disease) mediated these causal associations (all P < 0.05). Conclusions: BMI, WC, and WBFM are potential risk factors for HF, and the correlation between WBFM and HF was significantly stronger than that between BMI and WC, and HF. EA, UWP, and TC are potential protective factors against HF. Common risk factors for HF mediate these causal pathways. Early identification of potential risk or protective factors for HF patients from the dimension of nutritional status is expected to further improve patient outcomes.
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RATIONALE: The purpose of this article is to discuss the characteristics, diagnosis, treatment, and outcomes of cases of multiple coronary embolism (CE) highly suspected to be caused by a dislodged aneurysm of the ventricular membranous septum (AVMS) thrombus. PATIENT CONCERNS: A 35-year-old man was rushed to the Chest Pain Center of Taicang TCM Hospital Affiliated to Nanjing University of Chinese Medicine for sudden onset of chest pain. The patient had severe and persistent chest pain without relief, accompanied by sweating throughout the body. DIAGNOSIS: An electrocardiogram showed ST-segment elevation in the inferior wall leads, and blood tests suggested elevated troponin I levels. The initial diagnosis was acute ST-segment elevation myocardial infarction. Emergency coronary angiography revealed complete occlusion of the first diagonal branch, thrombolysis in myocardial infarction grade 0 flow, and smooth remaining vessels. Complete occlusion of the left anterior descending artery unexpectedly occurred during interventional treatment. Postoperative cardiac ultrasonography revealed the presence of a thrombus within the AVMS and in the apical portion of the heart. The final diagnosis was a CE. INTERVENTIONS: Intraoperatively, the diagonal branch occluded segment was dilated with a balloon and intracoronary administration of tirofiban and nitroglycerin. Postoperatively, antithrombotic therapy (aspirin, clopidogrel, and rivaroxaban) was administered. OUTCOMES: Ten days after admission, a repeat coronary angiography showed complete restoration of left anterior descending artery flow on its own, balloon dilation was again performed on the diagonal branch, and flow was restored to thrombolysis in myocardial infarction grade 1. Six months later, the intracardiac thrombus disappeared on repeat cardiac ultrasound. LESSONS: AVMS is a potential source of embolism in patients with CE. CE has features that distinguish it from atherosclerosis, and a timely and correct diagnosis can help improve patient clinical outcomes.
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Enfermedad de la Arteria Coronaria , Embolia , Infarto del Miocardio , Trombosis , Masculino , Humanos , Adulto , Angiografía Coronaria/efectos adversos , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/etiología , Enfermedad de la Arteria Coronaria/complicaciones , Trombosis/complicaciones , Embolia/complicaciones , Electrocardiografía , Arritmias Cardíacas/complicaciones , Dolor en el Pecho/complicacionesRESUMEN
Introduction: Heart Failure (HF) is a key area of research in human medicine, and traditional Chinese medicine (TCM) is an important branch of this field. This study aimed to use bibliometric methods to sort out the trajectory of TCM research on HF in this century (2000-2022) from a high dimension and to analyze its characteristics, hotspots and frontiers. Methods: In this study, the search formula "TS=(("traditional Chinese medicine") OR ("Chinese medicine")) AND TS=("heart failure")" was used to find relevant studies included in the Web of Science Core Collection from 2000 to 2022. Targeted literature records were analyzed and mapped using CiteSpace and VOSviewer. Results: The authors and collaborators of this study were still in the formation process, but several well-known scholars were included: YONG WANG, WEI WANG, etc. The main research institutions in this research area were Beijing Univ Chinese Med, China Acad Chinese Med Sc, etc. The main country of study was China. Current research hotspots and frontiers were Qili Qiangxin capsules, extracts (Tanshinone â ¡A, Panax ginseng, etc.), cardiac hypertrophy, ventricular remodeling, oxidative stress, signaling pathways, network pharmacology, etc. Influential journals that publish papers in this field were the Journal of Ethnopharmacology, Scientific Reports, Biomedicine & Pharmacotherapy, etc. The top 3 co-cited journals were Circulation, J ethnopharmacol, and J am coll cardiol. Conclusions: We analyzed valuable details in TCM research on HF in the 21st century, which may help researchers identify potential collaborators and partner institutions, hotspots, and frontiers in the field.
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Most cases of acquired aplastic anemia (AA) arise from autoimmune destruction of hematopoietic stem and progenitor cells. Human leukocyte antigen (HLA)-haploidentical nonmyeloablative hematopoietic stem cell transplantation (HSCT) plus post-transplantation cyclophosphamide (PTCy) is increasingly applied to salvage AA using bone marrow as graft and anti-thymocyte globulin (ATG) in conditioning. Herein, we characterize a cohort of twelve AA patients clinically and molecularly, six who possessed other immunological disorders (including two also carrying germline SAMD9L mutations). Each patient with SAMD9L mutation also carried an AA-related rare BCORL1 variant or CTLA4 p.T17A GG genotype, respectively, and both presented short telomere lengths. Six of the ten patients analyzed harbored AA-risky HLA polymorphisms. All patients recovered upon non-HSCT (n = 4) or HSCT (n = 8) treatments. Six of the eight HSCT-treated patients were subjected to a modified PTCy-based regimen involving freshly prepared peripheral blood stem cells (PBSC) as graft and exclusion of ATG. All patients were engrafted between post-transplantation days +13 and +18 and quickly reverted to normal life, displaying a sustained complete hematologic response and an absence of graft-versus-host disease. These outcomes indicate most AA cases, including of the SAMD9L-inherited subtype, are immune-mediated and the modified PTCy-based regimen we present is efficient and safe for salvage.
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Anemia Aplásica , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Niño , Suero Antilinfocítico/uso terapéutico , Anemia Aplásica/genética , Anemia Aplásica/terapia , Acondicionamiento Pretrasplante , Enfermedad Injerto contra Huésped/etiología , Ciclofosfamida/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Antígenos HLA , Estudios RetrospectivosRESUMEN
AIMS: Research evidence indicates that epigenetic modifications of gametes in obese or diabetic parents may contribute to metabolic disorders in offspring. In the present study, we sought to address the effect of diabetic uterine environment on the offspring metabolism. METHODS: Type 2 diabetes mouse model was induced by high-fat diet combined with streptozotocin (STZ) administration. We maintained other effect factors constant and changed uterine environment by zygote transfers, and then determined and compared the offspring numbers, symptoms, body weight trajectories, and metabolism indices from different groups. RESULT: We found that maternal type 2 diabetes mice had lower fertility and a higher dystocia rate, accompanying the increased risk of offspring malformations and death. Compared to only a pre-gestational exposure to hyperglycemia, exposure to hyperglycemia both pre- and during pregnancy resulted in offspring growth restriction and impaired metabolism in adulthood. But there was no significant difference between a pre-gestational exposure group and a no exposure group. The deleterious effects, no matter bodyweight or glucose tolerance, could be rescued by transferring the embryos from diabetic mothers into normal uterine environment. CONCLUSION: Our data demonstrate that uterine environment of maternal diabetes makes critical impact on the offspring health.
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RNA-binding proteins (RBPs) have essential functions during germline and early embryo development. However, current methods are unable to identify the in vivo targets of a RBP in these low-abundance cells. Here, by coupling RBP-mediated reverse transcription termination with linear amplification of complementary DNA ends and sequencing, we present the LACE-seq method for identifying RBP-regulated RNA networks at or near the single-oocyte level. We determined the binding sites and regulatory mechanisms for several RBPs, including Argonaute 2 (Ago2), Mili, Ddx4 and Ptbp1, in mature mouse oocytes. Unexpectedly, transcriptomics and proteomics analysis of Ago2-/- oocytes revealed that Ago2 interacts with endogenous small interfering RNAs (endo-siRNAs) to repress mRNA translation globally. Furthermore, the Ago2 and endo-siRNA complexes fine-tune the transcriptome by slicing long terminal repeat retrotransposon-derived chimeric transcripts. The precise mapping of RBP-binding sites in low-input cells opens the door to studying the roles of RBPs in embryonic development and reproductive diseases.
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Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Oocitos/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Sitios de Unión , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Células HeLa , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Humanos , Células K562 , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Proteína de Unión al Tracto de Polipirimidina/genética , Proteína de Unión al Tracto de Polipirimidina/metabolismo , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas de Unión al ARN/genética , RNA-Seq , TranscriptomaRESUMEN
Parathyroid hormone-related protein (PTHrP), the main cause of humoral hypercalcemia in malignancies, promotes cell proliferation and delays terminal cell maturation during embryonic development. Our previous study reported that PTHrP plays important roles in blastocyst formation, pluripotency gene expression, and histone acetylation during mouse preimplantation embryonic development. In this study, we further investigated the mechanism of preimplantation embryonic development regulated by PTHrP. Our results showed that Pthrp depletion decreased both the developmental rate of embryos at the cleavage stage and the cell number of morula-stage embryos. Pthrp-depleted embryos had significantly decreased levels of cyclin D1, phospho (p)-AKT (Thr308) and E2F1. However, Pthrp depletion did not cause significant changes in CDK4, ß-catenin or RUNX2 expression. In addition, our results indicated that Pthrp depletion promoted HDAC4 translocation from the cytoplasm to the nucleus in cleavage-stage embryos by stimulating the activity of protein phosphatase 2A (PP2A), which resulted in dephosphorylation of HDAC4. Taken together, these results suggest that PTHrP regulates cleavage division progression and blastocyst formation through the AKT/cyclin D1 pathway and that PTHrP modulates histone acetylation patterns through nuclear translocation of HDAC4 via PP2A-dependent HDAC4 dephosphorylation during preimplantation embryonic development in mice.
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Blastocisto/metabolismo , Ciclina D1/metabolismo , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Acetilación , Transporte Activo de Núcleo Celular , Animales , Factor de Transcripción E2F1/genética , Factor de Transcripción E2F1/metabolismo , Desarrollo Embrionario , Regulación del Desarrollo de la Expresión Génica , Histona Desacetilasas/genética , Ratones , Proteína Relacionada con la Hormona Paratiroidea/genética , Fosforilación , Proteína Fosfatasa 2/metabolismo , Transducción de SeñalRESUMEN
Ca2+ participates in many important cellular processes, but the underlying mechanisms are still poorly understood, especially during oocyte maturation. First, we confirmed that calcium in the culture medium was essential for oocyte maturation. Next, various inhibitors of Ca2+ channels were applied to investigate their roles in mitochondrial Ca2+ changes and oocyte maturation. Our results showed that Trmp7, Orai, T-type Ca2+ channels and Na+ /Ca2+ exchanger complex (NCLX) were important for oocyte maturation. Trmp7 inhibition delayed germinal vesicle breakdown. Orai and NCLX inhibition significantly weakened the distribution of mitochondrial Ca2+ around the nucleus compared to the Ctrl group. Interestingly, even T-type Ca2+ channels-specific inhibitor Mibefradil blocked germinal vesicle breakdown; mitochondrial Ca2+ surrounding the nucleus still was maintained at a high level without spindle formation. Two calcium transporter inhibitors, Thapsigargin and Ruthenium Red, which have been confirmed to inhibit oocyte activation, did not significantly affect oocyte maturation. Increasing the knowledge of calcium transport may provide a basis to build on for improving oocyte in vitro maturation in human assisted reproduction clinics.
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Calcio/metabolismo , Técnicas de Maduración In Vitro de los Oocitos , Proteínas de Transporte de Membrana/metabolismo , Mitocondrias/metabolismo , Oocitos/citología , Oocitos/metabolismo , Animales , Membrana Celular/metabolismo , Supervivencia Celular , Citoplasma/metabolismo , Femenino , Ratones Endogámicos ICRRESUMEN
In vitro culture of follicles is a promising technology to generate large quantities of mature oocytes and it could offer a novel option of assisted reproductive technologies. Here we described a 2-dimensional follicular serum-free culture system with 3-dimensional effect that can make secondary follicles develop into antral follicles (78.52%), generating developmentally mature oocytes in vitro (66.45%). The oocytes in this serum-free system completed the first meiosis; spindle assembly and chromosome congression in most oocytes matured from follicular culture were normal. However, these oocytes showed significantly lower activation and embryonic development rates, and their ability to produce Ca2+ oscillations was also lower in response to parthenogenetic activation, after which a 2-cell embryonic developmental block occurred. Oocytes matured from follicular culture displayed increased abnormal mitochondrial distribution and increased reactive oxygen species levels when compared to in vivo matured oocytes. These data are important for understanding the reasons for reduced developmental potential of oocytes matured from follicular culture, and for further improving the cultivation system.
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Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos , Folículo Ovárico , Animales , Núcleo Celular , Citoplasma , Femenino , Ratones , Oocitos/fisiologíaRESUMEN
Oocyte activation deficiency leads to female infertility. [Ca2+ ]i oscillations are required for mitochondrial energy supplement transition from the resting to the excited state, but the underlying mechanisms are still very little known. Three mitochondrial Ca2+ channels, Mitochondria Calcium Uniporter (MCU), Na+ /Ca2+ Exchanger (NCLX) and Voltage-dependent Ca2+ Channel (VDAC), were deactivated by inhibitors RU360, CGP37157 and Erastin, respectively. Both Erastin and CGP37157 inhibited mitochondrial activity significantly while attenuating [Ca2+ ]i and [Ca2+ ]m oscillations, which caused developmental block of pronuclear formation. Thus, NCLX and VDAC are two mitochondria-associated Ca2+ transporter proteins regulating oocyte activation, which may be used as potential targets to treat female infertility. SIGNIFICANCE OF THE STUDY: NCLX and VDAC are two mitochondria-associated Ca2+ transporter proteins regulating oocyte activation.
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Canales de Calcio/metabolismo , Calcio/metabolismo , Oocitos/metabolismo , Animales , Canales de Calcio/química , Femenino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos ICR , Mitocondrias/metabolismo , Oocitos/citología , Oocitos/efectos de los fármacos , Compuestos de Rutenio/farmacología , Rojo de Rutenio/farmacología , Intercambiador de Sodio-Calcio/antagonistas & inhibidores , Intercambiador de Sodio-Calcio/metabolismo , Tiazepinas/farmacología , Canales Aniónicos Dependientes del Voltaje/antagonistas & inhibidores , Canales Aniónicos Dependientes del Voltaje/metabolismoRESUMEN
In vitro maturation of oocytes is a promising assisted reproductive technology (ART) for infertility treatment, although it is still not a routine technique for human ART due to reduced embryonic development. The aim of the present study was to clarify the possible reasons for reduced capacity of in vitro matured oocytes. Our results showed that the oocytes matured in vitro displayed increased abnormal mitochondrial distribution, reduced mitochondrial membrane potential, and increased reactive oxygen species levels when compared to in vivo matured oocytes. These results were not different in oocytes matured in vitro with or without cumulus cells. Notably, in vitro matured oocytes displayed increased mitochondrial DNA numbers probably due to functional compensation. In vitro matured oocytes showed significantly lower activation and embryonic development rates, and their ability to produce Ca2+ oscillations was much lower in response to parthenogenetic activation, especially in oocytes matured in vitro without cumulus cells with nearly half of them failing to produce calcium waves upon strontium chloride stimulation. These data are important for understanding the reasons for reduced developmental potential of in vitro matured oocytes and the importance of cumulus cells for oocyte quality.
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ADN Mitocondrial/genética , Técnicas de Maduración In Vitro de los Oocitos/métodos , Mitocondrias/genética , Oocitos/crecimiento & desarrollo , Animales , Células del Cúmulo/metabolismo , Desarrollo Embrionario/genética , Femenino , Humanos , Ratones , Mitocondrias/metabolismo , Recuperación del Oocito/métodos , Oocitos/metabolismo , Embarazo , Especies Reactivas de Oxígeno/metabolismo , Técnicas Reproductivas AsistidasRESUMEN
Precise regulation of chromosome segregation during oocyte meiosis is of vital importance to mammalian reproduction. Anaphase promoting complex/cyclosome (APC/C) is reported to play an important role in metaphase-to-anaphase transition. Here we report that cell division cycle 23 (Cdc23, also known as APC8) plays a critical role in regulating the oocyte chromosome separation. Cdc23 localized on the meiotic spindle, and microinjection of Cdc23 siRNA caused decreased ratios of metaphase-to-anaphase transition. Loss of Cdc23 resulted in abnormal spindles, misaligned chromosomes, errors of homologous chromosome segregation, and production of aneuploid oocytes. Further study showed that inactivation of spindle assembly checkpoint and degradation of Cyclin B1 and securin were disturbed after Cdc23 knockdown. Furthermore, we found that inhibiting spindle assembly checkpoint protein Msp1 partly rescued the decreased polar body extrusion and reduced the accumulation of securin in Cdc23 knockdown oocytes. Taken together, our data demonstrate that Cdc23 is required for the chromosome segregation through regulating the spindle assembly checkpoint activity, and cyclin B1 and securin degradation in meiotic mouse oocytes.
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Subunidad Apc8 del Ciclosoma-Complejo Promotor de la Anafase/metabolismo , Segregación Cromosómica , Meiosis , Oocitos/fisiología , Huso Acromático/fisiología , Animales , Subunidad Apc8 del Ciclosoma-Complejo Promotor de la Anafase/genética , Proteínas de Ciclo Celular , Femenino , Ratones , Ratones Endogámicos ICR , Oocitos/citologíaRESUMEN
Oocyte meiotic maturation failure and unfaithful chromosome segregation are major causes for female infertility. Here, we showed that CENP-W, a relatively novel member of the kinetochore protein family, was expressed in mouse oocytes from the germinal vesicle (GV) to metaphase II (MII) stages. Confocal microscopy revealed that CENP-W was localized in the germinal vesicle in the GV stage, and then became concentrated on kinetochores during oocyte maturation. Knockdown of CENP-W by specific siRNA injection in vitro caused kinetochore-microtubule detachment, resulting in severely defective spindles and misaligned chromosomes, leading to metaphase I arrest and failure of first polar body (PB1) extrusion. Correspondingly, spindle assembly checkpoint (SAC) activation was observed in CENP-W knockdown oocytes even after 10h of culture. Our results suggest that CENP-W acts as a kinetochore protein, which takes part in kinetochore-microtubule attachment, thus mediating the progression of oocyte meiotic maturation.
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Cinetocoros/metabolismo , Meiosis , Microtúbulos/metabolismo , Oocitos/citología , Animales , Femenino , Ratones , Ratones Endogámicos ICR , Oocitos/metabolismoRESUMEN
Diabetes affects oocyte nuclear and cytoplasmic quality. In this study, we generated a type 1 diabetes (T1D) mouse model by STZ injection to study the effects of T1D on zona pellucida and genomic DNA methylation of oocytes and granulosa cells. T1D mice showed fewer ovulated oocytes, reduced ovarian reserve, disrupted estrus cycle, and significantly ruptured zona pellucida in 2-cell in vivo embryos compared to controls. Notably, diabetic oocytes displayed thinner zona pellucida and treatment of oocytes with high concentration glucose reduced the zona pellucida thickness. Differential methylation genes in oocytes and granulosa cells were analyzed by methylation sequencing. These genes were significantly enriched in GO terms by GO analysis, and these GO terms were involved in multiple aspects of growth and development. Most notably, the abnormal methylation genes in oocytes may be related to oocyte zona pellucida changes in diabetic mice. These findings provide novel basic data for further understanding and elucidating dysgenesis and epigenetic changes in type 1 diabetes mellitus.
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Metilación de ADN , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/genética , Células de la Granulosa/química , Oocitos/química , Zona Pelúcida/metabolismo , Animales , Estudios de Casos y Controles , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/metabolismo , Epigénesis Genética , Ciclo Estral , Femenino , Redes Reguladoras de Genes , Ratones , Análisis de Secuencia de ADN , EstreptozocinaRESUMEN
Mitochondrial DNA (mtDNA) is important for oxidative phosphorylation; dysfunctions can play a role in many mitochondrial diseases and can also affect the aging of cells and individuals. DNA methylation is an important epigenetic modification that plays a critical role in regulating gene expression. While recent studies have revealed the existence of mtDNA methylation there are still controversies about mtDNA methylation due to the special structure of mtDNA. Mitochondria and DNA methylation are both essential for regulating oocyte maturation and early embryo development, but whether mtDNA methylation changes during this process is unknown. By employing bisulfite sequencing, we found that in the process of mouse oocyte maturation, postovulatory oocyte aging, and early embryo development, all analyzed mitochondrial genes, including 16S-CpGI, DCR, ND6, 12S, and ATP8, lacked 5'mC. Thus, mtDNA methylation does not occur in the oocyte and early embryo.