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1.
Blood ; 143(9): 822-832, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38048694

RESUMO

ABSTRACT: CD20 is an established therapeutic target in B-cell malignancies. The CD20 × CD3 bispecific antibody mosunetuzumab has significant efficacy in B-cell non-Hodgkin lymphomas (NHLs). Because target antigen loss is a recognized mechanism of resistance, we evaluated CD20 expression relative to clinical response in patients with relapsed and/or refractory NHL in the phase 1/2 GO29781 trial investigating mosunetuzumab monotherapy. CD20 was studied using immunohistochemistry (IHC), RNA sequencing, and whole-exome sequencing performed centrally in biopsy specimens collected before treatment at predose, during treatment, or upon progression. Before treatment, most patients exhibited a high proportion of tumor cells expressing CD20; however, in 16 of 293 patients (5.5%) the proportion was <10%. Analyses of paired biopsy specimens from patients on treatment revealed that CD20 levels were maintained in 29 of 30 patients (97%) vs at progression, where CD20 loss was observed in 11 of 32 patients (34%). Reduced transcription or acquisition of truncating mutations explained most but not all cases of CD20 loss. In vitro modeling confirmed the effects of CD20 variants identified in clinical samples on reduction of CD20 expression and missense mutations in the extracellular domain that could block mosunetuzumab binding. This study expands the knowledge about the occurrence of target antigen loss after anti-CD20 therapeutics to include CD20-targeting bispecific antibodies and elucidates mechanisms of reduced CD20 expression at disease progression that may be generalizable to other anti-CD20 targeting agents. These results also confirm the utility of readily available IHC staining for CD20 as a tool to inform clinical decisions. This trial was registered at www.ClinicalTrials.gov as #NCT02500407.


Assuntos
Anticorpos Biespecíficos , Antineoplásicos , Linfoma de Células B , Humanos , Antígenos CD20/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Antineoplásicos/uso terapêutico
2.
BMC Biol ; 21(1): 43, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829148

RESUMO

BACKGROUND: Undernourishment in utero has deleterious effects on the metabolism of offspring, but the mechanism of the transgenerational transmission of metabolic disorders is not well known. In the present study, we found that undernourishment in utero resulted in metabolic disorders of female F1 and F2 in mouse model. RESULTS: Undernutrition in utero induced metabolic disorders of F1 females, which was transmitted to F2 females. The global methylation in oocytes of F1 exposed to undernutrition in utero was decreased compared with the control. KEGG analysis showed that genes with differential methylation regions (DMRs) in promoters were significantly enriched in metabolic pathways. The altered methylation of some DMRs in F1 oocytes located at the promoters of metabolic-related genes were partially observed in F2 tissues, and the expressions of these genes were also changed. Meanwhile, the abnormal DNA methylation of the validated DMRs in F1 oocytes was also observed in F2 oocytes. CONCLUSIONS: These results indicate that DNA methylation may mediate the transgenerational inheritance of metabolic disorders induced by undernourishment in utero via female germline.


Assuntos
Desnutrição , Doenças Metabólicas , Camundongos , Animais , Feminino , Epigênese Genética , Metilação de DNA , Oócitos
3.
Ann Surg ; 277(6): e1313-e1323, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35793069

RESUMO

OBJECTIVE: The purpose of this study was to determine the prevalence of psychiatric diagnoses among a sample of breast reconstruction patients and measure the association between these diagnoses and reconstruction-related, patient-reported outcomes. BACKGROUND: The impact of psychiatric disorders in conjunction with breast cancer diagnosis, treatment, and reconstruction have the potential to cause significant patient distress but remains not well understood. METHODS: A retrospective review of postmastectomy breast reconstruction patients from 2007 to 2018 at Memorial Sloan Kettering Cancer Center was conducted. Patient demographics, comorbidities, cancer characteristics, psychiatric diagnoses, and BREAST-Q Reconstruction Module scores (measuring satisfaction with breast, well-being of the chest, psychosocial, and sexual well-being) at postoperative years 1 to 3 were examined. Mixed-effects models and cross-sectional linear regressions were conducted to measure the effect of psychiatric diagnostic class type and number on scores. RESULTS: Of 7414 total patients, 50.1% had at least 1 psychiatric diagnosis. Patients with any psychiatric diagnoses before reconstruction had significantly lower BREAST-Q scores for all domains at all time points. Anxiety (50%) and depression (27.6%) disorders were the most prevalent and had the greatest impact on BREAST-Q scores. Patients with a greater number of psychiatric diagnostic classes had significantly worse patient-reported outcomes compared with patients with no psychiatric diagnosis. Psychosocial (ß: -7.29; 95% confidence interval: -8.67, -5.91), and sexual well-being (ß: -7.99; 95% confidence interval: -9.57, -6.40) were most sensitive to the impact of psychiatric diagnoses. CONCLUSIONS: Mental health status is associated with psychosocial and sexual well-being after breast reconstruction surgery as measured with the BREAST-Q. Future research will need to determine what interventions (eg, screening, early referral) can help improve outcomes for breast cancer patients with psychiatric disorders undergoing breast reconstruction.


Assuntos
Neoplasias da Mama , Mamoplastia , Transtornos Mentais , Humanos , Feminino , Neoplasias da Mama/etiologia , Mastectomia/efeitos adversos , Satisfação do Paciente , Qualidade de Vida , Estudos Transversais , Mamoplastia/efeitos adversos , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Medidas de Resultados Relatados pelo Paciente , Satisfação Pessoal
4.
Ann Surg Oncol ; 30(4): 2069-2084, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36600098

RESUMO

BACKGROUND: National databases are a rich source of epidemiologic data for breast surgical oncology research. However, these databases differ in the demographic, surgical, and oncologic variables provided. This study aimed to compare the strengths and limitations of four national databases in the context of breast surgical oncology research. METHODS: The study comprised a descriptive analysis of four national databases (the National Surgical Quality Improvement Program [NSQIP], the Nationwide Inpatient Sample [NIS], the Surveillance, Epidemiology and End Results [SEER] program, and the National Cancer Database [NCDB]) to assess their strengths and limitations in the context of breast surgical oncology. The study assessed the data available in each database for female patients with a breast cancer diagnosis between 2007 and 2017, and compared patient age, ethnicity, and race distributions. RESULTS: Data from 3.9 million female patients were examined, with most patients being between 60 and 69 years of age, non-Hispanic, and white. Age, ethnicity, and race distributions were similar in the databases. The NSQIP includes data on operative details, comorbidities, and postoperative outcomes. The NIS provides health services and inpatient utilization information, but does not evaluate outpatient procedures. The SEER program provides population-based oncologic detail including stage, histology, and neoadjuvant/adjuvant treatment. The NCDB offers hospital-based oncologic information and the largest population in the study period, with approximately 2.5 million breast cancer patients. CONCLUSION: Epidemiologic datasets offer tremendous potential for the examination of oncologic breast surgery, with each database providing unique data useful for addressing different epidemiologic questions. Understanding the strengths and limitations of each database creates a more efficient and productive research environment.


Assuntos
Neoplasias da Mama , Oncologia Cirúrgica , Humanos , Feminino , Estados Unidos/epidemiologia , Estudos Retrospectivos , Etnicidade , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Complicações Pós-Operatórias/epidemiologia , Bases de Dados Factuais
5.
FASEB J ; 36(6): e22357, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35593531

RESUMO

The reproductive life span of females is largely determined by the number and quality of oocytes. Previously, we identified MEIOK21 as a meiotic recombination regulator required for male fertility. Here, we characterize the important roles of MEIOK21 in regulating female meiosis and oocyte number and quality. MEIOK21 localizes at recombination sites as a component of recombination bridges in oogenesis like in spermatogenesis. Meiok21-/- female mice show subfertility. Consistently, the size of the primordial follicle pool in Meiok21-/- females is only ~40% of wild-type females because a great number of oocytes with defects in meiotic recombination and/or synapsis are eliminated. Furthermore, the numbers of primordial and growing follicles show a more marked decrease in an age-dependent manner compared with wild-type females. Further analysis shows Meiok21-/- oocytes also have reduced rates of germinal vesicle breakdown and the first polar body extrusion when cultured in vitro, indicating poor oocyte quality. Additionally, Meiok21-/- oocytes have more chromosomes bearing a single distally localized crossover (chiasmata), suggesting a possible defect in crossover maturation. Taken together, our findings indicate critical roles for MEIOK21 in ensuring the number and quality of oocytes in the follicles.


Assuntos
Meiose , Oócitos , Animais , Feminino , Recombinação Homóloga , Masculino , Meiose/genética , Camundongos , Oócitos/metabolismo , Oogênese/genética , Folículo Ovariano
6.
Lancet Oncol ; 23(8): 1055-1065, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803286

RESUMO

BACKGROUND: Mosunetuzumab is a CD20 × CD3 T-cell-engaging bispecific monoclonal antibody that redirects T cells to eliminate malignant B cells. In a phase 1 study, mosunetuzumab was well tolerated and active in patients with relapsed or refractory B-cell lymphoma. We, therefore, aimed to evaluate the safety and anti-tumour activity of fixed-duration mosunetuzumab in patients with relapsed or refractory follicular lymphoma who had received two or more previous therapies. METHODS: We conducted a single-arm, multicentre, phase 2 study at 49 centres in seven countries (Australia, Canada, Germany, South Korea, Spain, UK, and USA). All patients were aged 18 years or older with histologically confirmed follicular lymphoma (grade 1-3a) and an Eastern Cooperative Oncology Group performance status of 0-1. Patients had disease that was relapsed or refractory to two or more previous lines of treatment, including an anti-CD20 therapy and an alkylating agent. Intravenous mosunetuzumab was administered in 21-day cycles with cycle 1 step-up dosing: 1 mg on cycle 1 day 1, 2 mg on cycle 1 day 8, 60 mg on cycle 1 day 15 and cycle 2 day 1, and 30 mg on day 1 of cycle 3 and onwards. Patients with a complete response by investigator assessment using the International Harmonisation Project criteria completed treatment after cycle 8, whereas patients with a partial response or stable disease continued treatment for up to 17 cycles. The primary endpoint was independent review committee-assessed complete response rate (as best response) in all enrolled patients; the primary efficacy analysis compared the observed IRC-assessed complete response rate with a 14% historical control complete response rate in a similar patient population receiving the pan class I PI3K inhibitor copanlisib. Safety was assessed in all enrolled patients. This study is registered with ClinicalTrials.gov, number NCT02500407, and is ongoing. FINDINGS: Between May 2, 2019, and Sept 25, 2020, we enrolled 90 patients. As of the data cutoff date (Aug 27, 2021), the median follow-up was 18·3 months (IQR 13·8-23·3). According to independent review committee assessment, a complete response was recorded in 54 patients (60·0% [95% CI 49·1-70·2]). The observed complete response rate was significantly higher than the historical control complete response rate with copanlisib of 14% (p<0·0001), thereby meeting the primary study endpoint. Cytokine release syndrome was the most common adverse event (40 [44%] of 90 patients) and was predominantly grade 1 (23 [26%] of 90) and grade 2 (15 [17%]), and primarily confined to cycle 1. The most common grade 3-4 adverse events were neutropenia or neutrophil count decreased (24 [27%] of 90 patients), hypophosphataemia (15 [17%]), hyperglycaemia (seven [8%]), and anaemia (seven [8%]). Serious adverse events occurred in 42 (47%) of 90 patients. No treatment-related grade 5 (ie, fatal) adverse event occurred. INTERPRETATION: Fixed-duration mosunetuzumab has a favourable safety profile and induces high rates of complete remissions, allowing potential administration as an outpatient regimen, in patients with relapsed or refractory follicular lymphoma and two or more previous therapies. FUNDING: F Hoffmann-La Roche and Genentech.


Assuntos
Anticorpos Biespecíficos , Antineoplásicos , Linfoma Folicular , Recidiva Local de Neoplasia , Anticorpos Biespecíficos/efeitos adversos , Antineoplásicos/efeitos adversos , Humanos , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Resultado do Tratamento
7.
Ecotoxicol Environ Saf ; 242: 113921, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35908531

RESUMO

Oocyte quality is essential for a successful pregnancy. 1-Nitropyrene (1-NP) is a widely distributed pollutant in the environment and is well-known for its mutagenicity and carcinogenicity. However, whether 1-NP has toxic effects on mammalian oocyte quality remains unknown. In the present study, we focused on the effect of 1-NP on oocyte maturation using mouse oocytes as an in vitro model. Our study showed that 1-NP exposure disrupted the meiotic spindle assembly and caused chromosome misalignment, further impaired first polar body extrusion, and significantly decreased the fertilization capability in mouse oocytes. Further investigation showed that the mitochondrial membrane potential (MMP) and ATP levels were decreased, and the expression of genes encoding components of the mitochondrial respiratory chain was inhibited in 1-NP exposed oocytes. Meanwhile, 1-NP exposure increased the levels of reactive oxygen species (ROS), inhibited the expression of genes encoding antioxidant enzymes, and increased the frequency of early apoptotic oocytes. Overall, our data suggest that 1-NP exposure disrupts mitochondrial function and intracellular redox balance, ultimately impairing oocyte maturation. These findings reveal the adverse effect of 1-NP exposure on oocyte quality.


Assuntos
Apoptose , Oogênese , Animais , Feminino , Mamíferos/metabolismo , Camundongos , Mitocôndrias , Oócitos , Estresse Oxidativo , Gravidez , Pirenos , Espécies Reativas de Oxigênio/metabolismo
8.
Knowl Based Syst ; 252: 109278, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-35783000

RESUMO

Coronavirus Disease 2019 (COVID-19) still presents a pandemic trend globally. Detecting infected individuals and analyzing their status can provide patients with proper healthcare while protecting the normal population. Chest CT (computed tomography) is an effective tool for screening of COVID-19. It displays detailed pathology-related information. To achieve automated COVID-19 diagnosis and lung CT image segmentation, convolutional neural networks (CNNs) have become mainstream methods. However, most of the previous works consider automated diagnosis and image segmentation as two independent tasks, in which some focus on lung fields segmentation and the others focus on single-lesion segmentation. Moreover, lack of clinical explainability is a common problem for CNN-based methods. In such context, we develop a multi-task learning framework in which the diagnosis of COVID-19 and multi-lesion recognition (segmentation of CT images) are achieved simultaneously. The core of the proposed framework is an explainable multi-instance multi-task network. The network learns task-related features adaptively with learnable weights, and gives explicable diagnosis results by suggesting local CT images with lesions as additional evidence. Then, severity assessment of COVID-19 and lesion quantification are performed to analyze patient status. Extensive experimental results on real-world datasets show that the proposed framework outperforms all the compared approaches for COVID-19 diagnosis and multi-lesion segmentation.

9.
Hum Mol Genet ; 28(20): 3422-3430, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31384951

RESUMO

Germ cell-derived genomic structure variants not only drive the evolution of species but also induce developmental defects in offspring. The genomic structure variants have different types, but most of them are originated from DNA double-strand breaks (DSBs). It is still not well known whether DNA DSBs exist in adult mammalian oocytes and how the growing and fully grown oocytes repair their DNA DSBs induced by endogenous or exogenous factors. In this study, we detected the endogenous DNA DSBs in the growing and fully grown mouse oocytes and found that the DNA DSBs mainly localized at the centromere-adjacent regions, which are also copy number variation hotspots. When the exogenous DNA DSBs were introduced by Etoposide, we found that Rad51-mediated homologous recombination (HR) was used to repair the broken DNA. However, the HR repair caused the chromatin intertwined and impaired the homologous chromosome segregation in oocytes. Although we had not detected the indication about HR repair of endogenous centromere-adjacent DNA DSBs, we found that Rad52 and RNA:DNA hybrids colocalized with these DNA DSBs, indicating that a Rad52-dependent DNA repair might exist in oocytes. In summary, our results not only demonstrated an association between endogenous DNA DSBs with genomic structure variants but also revealed one specific DNA DSB repair manner in oocytes.


Assuntos
Segregação de Cromossomos/fisiologia , Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Meiose/fisiologia , Oócitos/metabolismo , Animais , Segregação de Cromossomos/genética , Reparo do DNA/genética , Feminino , Infertilidade Feminina/genética , Masculino , Meiose/genética , Camundongos
10.
Bioinformatics ; 36(11): 3401-3408, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32134470

RESUMO

MOTIVATION: Recent studies have shown that RNA-sequencing (RNA-seq) can be used to measure mRNA of sufficient quality extracted from formalin-fixed paraffin-embedded (FFPE) tissues to provide whole-genome transcriptome analysis. However, little attention has been given to the normalization of FFPE RNA-seq data, a key step that adjusts for unwanted biological and technical effects that can bias the signal of interest. Existing methods, developed based on fresh-frozen or similar-type samples, may cause suboptimal performance. RESULTS: We proposed a new normalization method, labeled MIXnorm, for FFPE RNA-seq data. MIXnorm relies on a two-component mixture model, which models non-expressed genes by zero-inflated Poisson distributions and models expressed genes by truncated normal distributions. To obtain maximum likelihood estimates, we developed a nested EM algorithm, in which closed-form updates are available in each iteration. By eliminating the need for numerical optimization in the M-step, the algorithm is easy to implement and computationally efficient. We evaluated MIXnorm through simulations and cancer studies. MIXnorm makes a significant improvement over commonly used methods for RNA-seq expression data. AVAILABILITY AND IMPLEMENTATION: R code available at https://github.com/S-YIN/MIXnorm. CONTACT: swang@smu.edu. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Perfilação da Expressão Gênica , RNA , Formaldeído , Inclusão em Parafina , Análise de Sequência de RNA , Fixação de Tecidos
11.
Reproduction ; 162(1): 47-59, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33970124

RESUMO

Muscarinic acetylcholine receptor (mAChR) antagonists have been reported to decrease male fertility; however, the roles of mAChRs in spermatogenesis and the underlying mechanisms are not understood yet. During spermatogenesis, extensive remodeling between Sertoli cells and/or germ cells interfaces takes place to accommodate the transport of developing germ cells across the blood-testis barrier (BTB) and adluminal compartment. The cell-cell junctions play a vital role in the spermatogenesis process. This study used ICR male mice and spermatogonial cells (C18-4) and Sertoli cells (TM-4). shRNA of control or M5 gene was injected into 5-week-old ICR mice testes. Ten days post-viral grafting, mice were deeply anesthetized with pentobarbital and the testes were collected. One testicle was fresh frozen for RNA-seq analysis or Western blotting (WB). The second testicle was fixed for immunofluorescence staining (IHF). C18-4 or TM-4 cells were treated with shRNA of control or M5 gene. Then, the cells were collected for RNA-seq analysis, WB, or IHF. Knockdown of mAChR M5 disrupted mouse spermatogenesis and damaged the actin-based cytoskeleton and many types of junction proteins in both Sertoli cells and germ cells. M5 knockdown decreased Phldb2 expression in both germ cells and Sertoli cells which suggested that Phldb2 may be involved in cytoskeleton and cell-cell junction formation to regulate spermatogenesis. Our investigation has elucidated a novel role for mAChR M5 in the regulation of spermatogenesis through the interactions of Phldb2 and cell-cell junctions. M5 may be an attractive future therapeutic target in the treatment of male reproductive disorders.


Assuntos
Barreira Hematotesticular , Junções Intercelulares/fisiologia , Proteínas de Membrana/metabolismo , Receptor Muscarínico M5/metabolismo , Células de Sertoli/citologia , Espermatogênese , Testículo/citologia , Citoesqueleto de Actina , Animais , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos ICR , Microtúbulos/metabolismo , Receptor Muscarínico M5/genética , Células de Sertoli/metabolismo , Testículo/metabolismo
12.
Philos Trans A Math Phys Eng Sci ; 379(2207): 20200360, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34398651

RESUMO

A digital twin (DT) is classically defined as the virtual replica of a real-world product, system, being, communities, even cities that are continuously updated with data from its physical counterpart, as well as its environment. It bridges the virtual cyberspace with the physical entities and, as such, is considered to be the pillar of Industry 4.0 and the innovation backbone of the future. A DT is created and used throughout the whole life cycle of the entity it replicates, from cradle to grave, so to speak. This article focuses on the present state of the art of DTs, concentrating on the use of DTs in industry in the context of smart manufacturing, especially from the point of view of plantwide optimization. The main capabilities of DTs (mirroring, shadowing and threading) are discussed in this context. The article concludes with a perspective on the future. This article is part of the theme issue 'Towards symbiotic autonomous systems'.

13.
Biochem Biophys Res Commun ; 527(4): 1043-1049, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32439172

RESUMO

During oocyte meiosis, mitochondria usually surround spindle to meet the energy demand of spindle migration and chromosome segregation. Therefore, the mitochondrion surrounding spindle is widely accepted as an important indicator to demonstrate the mitochondrial function in oocyte studies. However, the role of mitochondria surrounding spindle in oocyte quality is not exactly addressed. Mitofusin-2 (MFN2) is a mitochondrial outer membrane GTPase that mediates mitochondrial clustering and fusion. Here, we increased the mitochondria surrounding spindle by overexpression of MFN2 in mouse oocytes. Results indicate that the increase of mitochondria surrounding spindle has little effect on germinal vesicle breakdown (GVBD), spindle migration, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) production and Endoplasmic reticulum (ER) distribution, while blocks chromosome segregation, destroys the spindle, and finally causes most of the oocytes to arrest at metaphase I stage. Collectively, our results demonstrate the mitochondria surrounding spindle is precisely regulated during oocyte maturation, while too much of it may cause abnormal oocyte meiosis. Therefore, although mitochondrion surrounding spindle is a typical biological event during oocyte maturation, utilizing it to demonstrate the mitochondrial function and oocyte quality should be much careful.


Assuntos
Metáfase , Mitocôndrias/metabolismo , Oócitos/citologia , Fuso Acromático/metabolismo , Animais , Células Cultivadas , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Células HeLa , Humanos , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/genética , Oócitos/metabolismo , Oogênese , Espécies Reativas de Oxigênio/metabolismo , Fuso Acromático/genética , Regulação para Cima
14.
Nature ; 511(7511): 551-6, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25043020

RESUMO

Spatial patterning is a ubiquitous feature of biological systems. Meiotic crossovers provide an interesting example, defined by the classic phenomenon of crossover interference. Here we identify a molecular pathway for interference by analysing crossover patterns in budding yeast. Topoisomerase II plays a central role, thus identifying a new function for this critical molecule. SUMOylation (of topoisomerase II and axis component Red1) and ubiquitin-mediated removal of SUMOylated proteins are also required. The findings support the hypothesis that crossover interference involves accumulation, relief and redistribution of mechanical stress along the protein/DNA meshwork of meiotic chromosome axes, with topoisomerase II required to adjust spatial relationships among DNA segments.


Assuntos
Troca Genética/genética , Meiose , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Cromossomos Fúngicos/genética , Cromossomos Fúngicos/metabolismo , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Mutação/genética , Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae/metabolismo , Sumoilação
15.
J Cell Physiol ; 234(5): 6220-6229, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30317565

RESUMO

Benzo[ghi]perylene (B[ghi]P) is a polycyclic aromatic hydrocarbon widely found in haze. Long-term exposure to humans or animals can cause serious damage to the respiratory system. Melatonin is an endogenous natural hormone synthesized and released by the pineal gland. In this study, we investigated the effects of melatonin on in vitro cultured B[ghi]P-exposed mouse oocytes and the protective roles of melatonin. Our data indicate that B[ghi]P exposure leads to meiotic maturation arrest and reduced ability of sperm binding and parthenogenetic activation. Also, B[ghi]P exposure disrupts actin filament dynamics, spindle assembly, and kinetochore-microtubule attachment stability, which results in oocyte aneuploidy. Simultaneously, B[ghi]P exposure disturbs the distribution of mitochondria, increases the level of oxidative stress, and induces apoptosis of oocytes. Whereas all of these toxic effects of B[ghi]P can be restored after melatonin supplement. In conclusion, our findings validate that melatonin has a certain protective effect on preventing the reduced oocyte quality caused by B[ghi]P exposure during meiotic maturation in mouse oocytes.


Assuntos
Antioxidantes/farmacologia , Melatonina/farmacologia , Oócitos/efeitos dos fármacos , Perileno/análogos & derivados , Animais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos , Perileno/toxicidade
16.
J Cell Biochem ; 120(1): 715-726, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30191590

RESUMO

Tributyltin oxide (TBTO) has been widely used as marine antifouling composition, preservative, biocide, and a stabilizer in plastic industry. Previous studies have indicated that TBTO can cause immunotoxicity as an environmental pollutant. However, little is known about its reproductive toxicity, especially on female oocyte maturation and the underlying mechanisms. In this study, mouse oocytes were cultured with different concentrations of TBTO in vitro, and several crucial events during meiotic maturation were evaluated. We found that the first polar body extrusion rate was significantly reduced, which reflected the disruption of meiotic maturation. The rate of abnormal spindle organization increased significantly, accompanied with a higher rate of chromosome misalignment. In addition, TBTO treatment increased reactive oxygen species generation markedly, which also accelerated the early-stage apoptosis. Moreover, heterogeneous mitochondrial distribution, mitochondrial dysfunction, and higher rate of aneuploidy were detected, which consequently disrupted in vitro fertilization. In conclusion, our results indicated that TBTO exposure could impair mouse oocyte maturation by affecting spindle organization, chromosome alignment, mitochondria functions, oxidative stress, and apoptosis.


Assuntos
Aneugênicos/farmacologia , Oogênese/efeitos dos fármacos , Corpos Polares/metabolismo , Compostos de Trialquitina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Troca Genética/efeitos dos fármacos , Feminino , Fertilização in vitro/efeitos dos fármacos , Meiose/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fuso Acromático/metabolismo
17.
Reproduction ; 157(6): 511-523, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30884466

RESUMO

It is demonstrated that repeated superovulation has deleterious effects on mouse ovaries and cumulus cells. However, little is known about the effects of repeated superovulation on early embryos. Epigenetic reprogramming is an important event in early embryonic development and could be easily disrupted by the environment. Thus, we speculated that multiple superovulations may have adverse effects on histone modifications in the early embryos. Female CD1 mice were randomly divided into four groups: (a) spontaneous estrus cycle (R0); (b) with once superovulation (R1); (c) with three times superovulation at a 7-day interval (R3) and (d) with five times superovulation at a 7-day interval (R5). We found that repeated superovulation remarkably decreased the fertilization rate. With the increase of superovulation times, the rate of early embryo development was decreased. The expression of Oct4, Sox2 and Nanog was also affected by superovulation in blastocysts. The immunofluorescence results showed that the acetylation level of histone 4 at lysine 12 (H4K12ac) was significantly reduced by repeated superovulation in mouse early embryos (P < 0.01). Acetylation level of histone 4 at lysine 16 (H4K16ac) was also significantly reduced in pronuclei and blastocyst along with the increase of superovulation times (P < 0.01). H3K9me2 and H3K27me3 were significantly increased in four-cell embryos and blastocysts. We further found that repeated superovulation treatment increased the mRNA level of histone deacetylases Hdac1, Hdac2 and histone methyltransferase G9a, but decreased the expression level of histone demethylase-encoding genes Kdm6a and Kdm6b in early embryos. In a word, multiple superovulations alter histone modifications in early embryos.


Assuntos
Blastocisto/fisiologia , Desenvolvimento Embrionário , Histonas/química , Processamento de Proteína Pós-Traducional , Superovulação/fisiologia , Acetilação , Animais , Blastocisto/citologia , Metilação de DNA , Técnicas de Cultura Embrionária , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Camundongos , Gravidez
19.
Hum Reprod ; 33(3): 474-481, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29377995

RESUMO

STUDY QUESTION: What are the effects of high-glucose concentrations on DNA methylation of human oocytes? SUMMARY ANSWER: High-glucose concentrations altered DNA methylation levels of Peg3 and Adiponectin in human in vitro maturation oocytes. WHAT IS KNOWN ALREADY: Maternal diabetes has a detrimental influence on oocyte quality including epigenetic modifications, as shown in non-human mammalian species. STUDY DESIGN, SIZE, DURATION: Immature metaphase I (MI) stage oocytes of good quality were retrieved from patients who had normal ovarian potential and who underwent ICSI in the Reproductive Medicine Center of People's Hospital of Zhengzhou University. MI oocytes were cultured in medium with different glucose concentrations (control, 10 mM and 15 mM) in vitro and 48 h later, oocytes with first polar body extrusion were collected to check the DNA methylation levels. PARTICIPANTS/MATERIALS, SETTING, METHODS: MI oocytes underwent in vitro maturation (IVM) at 37°C with 5% mixed gas for 48 h. Then the mature oocytes were treated with bisulfite buffer. Target sequences were amplified using nested or half-nested PCR and the DNA methylation status was tested using combined bisulfite restriction analysis (COBRA) and bisulfite sequencing (BS). MAIN RESULTS AND THE ROLE OF CHANCE: High-glucose concentrations significantly decreased the first polar body extrusion rate. Compared to controls, the DNA methylation levels of Peg3 in human IVM oocytes were significantly higher in 10 mM (P < 0.001) and 15 mM (P < 0.001) concentrations of glucose. But the DNA methylation level of H19 was not affected by high-glucose concentrations in human IVM oocytes. We also found that there was a decrease in DNA methylation levels in the promoter of adiponectin in human IVM oocytes between controls and oocytes exposed to 10 mM glucose (P = 0.028). LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: It is not clear whether the alterations are beneficial or not for the embryo development and offspring health. The effects of high-glucose concentrations on the whole process of oocyte maturation are still not elucidated. Another issue is that the number of oocytes used in this study was limited. WIDER IMPLICATIONS OF THE FINDINGS: This is the first time that the effects of high-glucose concentration on DNA methylation of human oocytes have been elucidated. Our result indicates that in humans, the high risk of chronic diseases in offspring from diabetic mothers may originate from abnormal DNA modifications in oocytes. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the fund of National Natural Science Foundation of China (81401198) and Doctor Foundation of Qingdao Agricultural University (1116008).The authors declare that there are no potential conflicts of interest relevant to this article.


Assuntos
Adiponectina/genética , Metilação de DNA/efeitos dos fármacos , Glucose/administração & dosagem , Fatores de Transcrição Kruppel-Like/genética , Oócitos/efeitos dos fármacos , Adiponectina/metabolismo , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Humanos , Técnicas de Maturação in Vitro de Oócitos , Fatores de Transcrição Kruppel-Like/metabolismo , Oócitos/metabolismo
20.
Phytother Res ; 32(8): 1574-1582, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29682805

RESUMO

Rhizome of Anemarrhena asphodeloides Bunge (AA, family Liliaceae) has been widely used in China for thousands of years to treat febrile diseases and diabetes. Steroidal saponins from AA show good antidiabetes effects and ameliorate diabetic complications. This study was designed to investigate the effects of sarsasapogenin (Sar), a major sapogenin from AA, on diabetic nephropathy (DN) in rats, and to explore the possible mechanisms. Diabetic rats were divided into 3 groups treated orally with Sar (0, 20, or 60 mg/kg) and carboxymethylcellulose sodium, whereas normal rats for Sar (0 or 60 mg/kg) and carboxymethylcellulose sodium. We found that chronic treatment with Sar for 9 weeks significantly ameliorated renal dysfunction of diabetic rats, as evidenced by decreases in albuminuria, kidney weight index, serum uric acid, and morphologic changes such as extracellular matrix expansion and accumulation (fibronectin and collagen IV levels, etc.). Meanwhile, Sar treatment resulted in decreases in interleukin-18, NLRP3, and activated caspase 1 levels as well as advanced glycation endproducts (AGEs) and their receptor (RAGE) levels in the renal cortex of diabetic rats. However, Sar has no effects on the above indices in the normal rats. Therefore, Sar can markedly ameliorate diabetic nephropathy in rats via inhibition of NLRP3 inflammasome activation and AGEs-RAGE interaction.


Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Espirostanos/farmacologia , Anemarrhena/química , Animais , China , Diabetes Mellitus Experimental/complicações , Medicamentos de Ervas Chinesas/farmacologia , Produtos Finais de Glicação Avançada , Interleucina-18/metabolismo , Rim/efeitos dos fármacos , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos , Ratos Sprague-Dawley , Rizoma/química , Saponinas/farmacologia , Ácido Úrico/sangue
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