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1.
Int J Mol Sci ; 25(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38542143

RESUMO

The emergence of targeted therapeutics in ovarian cancer, particularly poly (ADP-ribose) polymerase inhibitors (PARPi's), has created additional opportunities for patients seeking frontline and recurrent disease management options. In particular, PARPi's have shown clinical benefits in BRCA mutant and/or homologous recombination deficient (HRD) ovarian cancer. Until recently, response was thought to be limited in BRCA wild-type, homologous recombination proficient (HRP) cancers. Therefore, attempts have been made at combination therapy involving PARPi to improve patient outcomes. Additionally, immune checkpoint inhibitors (ICIs) have demonstrated underwhelming results involving ovarian cancer. Many are searching for reliable biomarkers of immune response to increase efficacy of ICI therapy involving ovarian cancer. In this review, we examine the evidence supporting the combination of PARPi and ICIs in ovarian cancer, which is still lacking.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Recombinação Homóloga , Biomarcadores
3.
Curr Probl Cardiol ; 49(2): 102233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38052347

RESUMO

Inflammation of the myocardium, or myocarditis, presents with varied severity, from mild to life-threatening such as cardiogenic shock or ventricular tachycardia storm. Existing data on sex-related differences in its presentation and outcomes are scarce. Using the Nationwide Readmission Database (2016-2019), we identified myocarditis hospitalizations and stratified them according to sex to either males or females. Multivariable regression analyses were used to determine the association between sex and myocarditis outcomes. The primary outcome was in-hospital mortality, and the secondary outcomes included sudden cardiac death (SCD), cardiogenic shock (CS), use of mechanical circulatory support (MCS), and 90-day readmissions. We found a total of 12,997 myocarditis hospitalizations, among which 4,884 (37.6 %) were females. Compared to males, females were older (51 ± 15.6 years vs. 41.9 ± 14.8 in males) and more likely to have connective tissue disease, obesity, and a history of coronary artery disease. No differences were noted between the two groups with regards to in-hospital mortality (adjusted odds ratio [aOR] 1.20; confidence interval [CI] 0.93-1.53; P = 0.16), SCD (aOR:1.18; CI 0.84-1.64; P = 0.34), CS (aOR: 1.01; CI 0.85-1.20;P = 0.87), or use of MCS (aOR: 1.07; CI:0.86-1.34; P = 0.56). In terms of interventional procedures, females had lower rates of coronary angiography (aOR: 0.78; CI 0.70-0.88; P < 0.01), however, similar rates of right heart catheterization (aOR 0.93; CI:0.79-1.09; P = 0.36) and myocardial biopsy (aOR: 1.16; CI:0.83-1.62; P = 0.38) compared to males. Additionally, females had a higher risk of 90-day all-cause readmission (aOR: 1.25; CI: 1.16-1.56; P < 0.01) and myocarditis readmission (aOR:1.58; CI 1.02-2.44; P = 0.04). Specific predictors of readmission included essential hypertension, congestive heart failure, malignancy, and peripheral vascular disease. In conclusion, females admitted with myocarditis tend to have similar in-hospital outcomes with males; however, they are at higher risk of readmission within 90 days from hospitalization. Further studies are needed to identify those at higher risk of readmission.


Assuntos
Miocardite , Choque Cardiogênico , Humanos , Masculino , Feminino , Choque Cardiogênico/epidemiologia , Choque Cardiogênico/terapia , Readmissão do Paciente , Miocardite/epidemiologia , Miocardite/terapia , Caracteres Sexuais , Estudos Retrospectivos , Hospitalização , Hospitais
4.
Am J Cardiol ; 210: 219-224, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37884110

RESUMO

We aimed to assess the overall clinical impact of cardiac myosin inhibitors in hypertrophic cardiomyopathy (HCM). We performed a meta-analysis of published trials assessing the effect of cardiac myosin inhibitors (mavacamten and aficamten) on resting and Valsalva left ventricular outflow tract (LVOT) gradients and functional capacity in symptomatic HCM. The co-primary outcomes were mean percent change (mean difference [MD]) from baseline in LVOT gradient at rest and Valsalva LVOT gradient and the proportion of patients achieving New York Heart Association class improvement ≥1. The secondary outcomes included the mean percent change from baseline N-terminal pro-B-type natriuretic peptide, troponin I, and left ventricular ejection fraction (LVEF). A total of 4 studies (all randomized controlled trials, including 3 mavacamten-focused and 1 aficamten-focused trials) involving 463 patients were included in the meta-analysis. Compared with placebo, the cardiac myosin inhibitor group demonstrated statistically significant differences in the baseline percent change in mean LVOT gradient at rest (MD -62.48, confidence interval [CI] -65.44 to -59.51, p <0.00001) and Valsalva LVOT gradient (MD -54.21, CI -66.05 to -42.36, p <0.00001) and the proportion of patients achieving New York Heart Association class improvement ≥1 (odds ratio 3.43, CI 1.90 to 6.20, p <0.0001). Regarding the secondary outcomes, the intervention group demonstrated statistically significant reductions in mean percent change from baseline in N-terminal pro-B-type natriuretic peptide (MD -69.41, CI -87.06 to -51.75, p <0.00001), troponin I (MD, -44.19, CI -50.59 to -37.78, p <0.00001), and LVEF (MD -6.31, CI -10.35, -2.27, p = 0.002). In conclusion, cardiac myosin inhibitors may confer clinical and symptomatic benefits in symptomatic HCM at the possible expense of LVEF. Further trials with large sample sizes are needed to confirm our findings.


Assuntos
Cardiomiopatia Hipertrófica , Peptídeo Natriurético Encefálico , Humanos , Volume Sistólico , Troponina I , Função Ventricular Esquerda , Cardiomiopatia Hipertrófica/tratamento farmacológico , Miosinas Cardíacas , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Curr Probl Cardiol ; 48(11): 101980, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37473936

RESUMO

Transcatheter aortic valve replacement (TAVR) is indicated for high-risk patients with severe degenerative aortic stenosis (AS). Given the shared risk factors and coexistence of obstructive coronary artery disease (CAD) and AS, there is inconsistent clinical data regarding potential survival benefits of paired percutaneous coronary intervention (PCI) with TAVR procedures. We performed a literature search using PubMed, Embase, and Cochrane Library from inception through June 2023 assessing the impact of concomitant PCI in patients with obstructive CAD undergoing TAVR. The primary outcomes were 30-day all-cause mortality, 30-day cardiovascular mortality, and 6 months-1 year all-cause mortality. Secondary outcomes included 30-day myocardial infarction, stroke, major bleeding complications, and acute kidney injury (AKI). A total of 11 studies involving 2804 patients were included in the final analysis. Compared to patients undergoing TAVR alone, the TAVR+PCI group showed no significant difference in 30-day all-cause mortality (RR 0.90, CI 0.66, 1.22, P = 0.49), 30-day cardiovascular mortality (RR 0.71 CI 0.44, 1.14, P = 0.16), or 6 months-1 year all-cause mortality (RR 0.94, CI 0.75, 1.18, P = 0.57). Regarding secondary outcomes, 30-day myocardial infarction was higher in the TAVR+PCI group (RR 3.09, CI 1.26, 7.57, P = 0.01), with no significant differences noted in rates of 30-day stroke (RR 1.14, CI 0.56, 2.33, P = 0.72), major bleeding/vascular complications (RR 1.11, CI 0.79, 1.56, P = 0.55), and AKI (RR 1.07, CI 0.75, 1.54, P = 0.71). Concomitant PCI does not confer any mortality benefit in patients with obstructive CAD and high-grade AS undergoing TAVR. Further trials are needed to confirm our findings.


Assuntos
Injúria Renal Aguda , Estenose da Valva Aórtica , Doença da Artéria Coronariana , Infarto do Miocárdio , Intervenção Coronária Percutânea , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estenose da Valva Aórtica/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Valva Aórtica/cirurgia , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Hemorragia/etiologia
6.
Am J Cardiol ; 198: 33-35, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37196531

RESUMO

Transcatheter aortic valve implantation (TAVI) has been increasingly performed among extreme elderly patients with symptomatic severe aortic stenosis. We aimed to study the trends, characteristics, and outcomes of TAVI among extreme elderly. The National Readmission Database for the years 2016 to 2019 was queried for extreme elderly who underwent TAVI. Linear regression analysis was used to calculate the temporal trends in outcomes. A total of 23,507 TAVI extreme elderly admissions (50.3% women and 95.9% Medicare insurance) were included. The in-hospital mortality and all-cause 30-day readmissions were 2% and 15% and have been stable over years of analysis (p trend = 0.79 and 0.06, respectively). We evaluated complications, such as permanent pacemaker implantation (12%) and stroke (3.2%). Stroke rates did not decrease (3.4% vs 2.9% in 2016 and 2019 [p trend = 0.24]). The mean length of stay improved from 5.5 days in 2016 to 4.3 days in 2019 (p trend <0.01). The rates of early discharge (day ≤3) has improved from 49% in 2016 to 69% in 2019 (p trend <0.01). In conclusion, this nationwide contemporary observational analysis showed that TAVI was associated with low rates of complications in the extreme elderly.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Idoso , Feminino , Humanos , Masculino , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Hospitalização , Medicare , Fatores de Risco , Acidente Vascular Cerebral/complicações , Resultado do Tratamento , Estados Unidos/epidemiologia
8.
Curr Probl Cardiol ; 48(2): 101455, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36280124

RESUMO

Supine hypertension-orthostatic hypotension disease poses a management challenge to clinicians. Data on short term outcomes of patients with orthostatic hypotension (OH) who are hospitalized with hypertensive (HTN) crises is lacking. The Nationwide Readmission Database 2016-2019 was queried for all hospitalizations of HTN crises. Hospitalizations were stratified according to whether OH was present or not. We employed propensity score to match hospitalizations for patients with OH to those without, at 1:1 ratio. Outcomes evaluated were 30-days readmission with HTN crises or falls, as well as hospital outcomes of in-hospital mortality, acute kidney injury, acute congestive heart failure, acute coronary syndrome, type 2 myocardial infarction, aortic dissection, stroke, length of stay (LOS), discharge to nursing home and hospitalization costs. We included a total of 9451 hospitalization (4735 in the OH group vs 4716 in the control group). OH group was more likely to be readmitted with falls (Odds ratio [OR]:3.27, P < 0.01) but not with HTN crises (P = 0.05). Both groups had similar likelihood of developing acute kidney injury (P = 0.08), stroke/transient ischemic attack (P = 0.52), and aortic dissection (P = 0.66). Alternatively, OH group were less likely to develop acute heart failure (OR:0.54, P < 0.01) or acute coronary syndrome (OR:0.39, P < 0.01) in the setting of HTN crises than non-OH group. OH group were more likely to have longer LOS and have higher hospitalization costs. Patients with OH who are admitted with HTN crises tend to have similar or lower HTN-related complications to non-OH group while having higher likelihood of readmission with falls, LOS and hospitalization costs. Further studies are needed to confirm such findings.


Assuntos
Síndrome Coronariana Aguda , Dissecção Aórtica , Insuficiência Cardíaca , Hipotensão Ortostática , Acidente Vascular Cerebral , Humanos , Hipotensão Ortostática/epidemiologia , Hipotensão Ortostática/terapia , Hipotensão Ortostática/complicações , Síndrome Coronariana Aguda/complicações , Hospitalização , Insuficiência Cardíaca/complicações
9.
J Card Surg ; 37(12): 5336-5340, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36335628

RESUMO

The standard practice for management for asymptomatic severe aortic stenosis with a normal left ventricular systolic function is conservative management with a few exceptions. This practice is challenged by two recent randomized controlled trials (RCT). All the prior data is observational. We performed a meta-analysis of these 2 RCTs to determine if early surgical aortic valve replacement in this patient population is beneficial compared with the standard conservative therapy.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Humanos , Estenose da Valva Aórtica/cirurgia , Tratamento Conservador , Valva Aórtica/cirurgia
10.
Am J Cardiol ; 171: 23-27, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35321805

RESUMO

This study aimed to study group differences in patients presenting with ST-elevation myocardial infarction (STEMI) based on the presence or absence of associated coronary artery aneurysms (CAA). The cause-and-effect relationship between CAAs and STEMI is largely unknown. The Nationwide Readmission database was used to identify and study group differences of patients with STEMI and with and without CAA from 2014 to 2018. The primary outcome in the 2 groups was mortality. Secondary outcomes in the 2 groups included differences in clinical outcomes, cardiovascular interventions performed, and prevalence of coronary artery dissection. The total number of patients with STEMI included was 1,038,299. In this sample, 1,543 (0.15%) had CAA. Compared with those without CAA, patients with CAAs and STEMI were younger (62.6 vs 65.4), more likely to be male (78 vs 66%), and had a higher prevalence of a history of Kawasaki disease (2.5 vs 0.01%). A difference exists in the prevalence of coronary dissection in patients with STEMI with and without CAA (73% vs 1%). Patients with CAA were more often treated with coronary artery bypass grafting (13.1 vs 5.6%), thrombectomy (16.5 vs 6%), and bare-metal stent implantation (8 vs 4.4). Patients in the CAA STEMI group had lower all-cause mortality (6.3 vs 11.7%). In conclusion, there are important differences in patients with STEMI with and without CAA, which include, but are not limited to, factors such as patient profile, the risk for coronary dissection, treatment, outcomes, and mortality.


Assuntos
Aneurisma Coronário , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Aneurisma Coronário/etiologia , Ponte de Artéria Coronária/efeitos adversos , Vasos Coronários , Feminino , Humanos , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Resultado do Tratamento , Estados Unidos/epidemiologia
11.
Oncol Rev ; 15(1): 534, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-34267890

RESUMO

Inactivating mutations of the adenomatous polyposis coli (APC) gene and consequential upregulation of the Wnt signaling pathway are critical initiators in the development of colorectal cancer (CRC), the third most common cancer in the United States for both men and women. Emerging evidence suggests APCmutations are also found in gastric, breast and other cancers. The APC gene, located on chromosome 5q, is responsible for negatively regulating the b-catenin/Wnt pathway by creating a destruction complex with Axin/Axin2, GSK-3b, and CK1. In the event of an APC mutation, b-catenin accumulates, translocates to the cell nucleus and increases the transcription of Wnt target genes that have carcinogenic consequences in gastrointestinal epithelial stem cells. A literature review was conducted to highlight carcinogenesis related to APC mutations, as well as preclinical and clinical studies for potential therapies that target steps in inflammatory pathways, including IL-6 transduction, and Wnt pathway signaling regulation. Although a range of molecular targets have been explored in murine models, relatively few pharmacological agents have led to substantial increases in survival for patients with colorectal cancer clinically. This article reviews a range of molecular targets that may be efficacious targets for tumors with APC mutations.

12.
Future Oncol ; 17(21): 2817-2830, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34058833

RESUMO

Patients who have mutations of the genes BRCA1 or BRCA2 are at an increased risk for developing breast and ovarian cancer. BRCA1/2 function as tumor suppressor genes, responsible for regulating DNA repair, and play an essential role in homologous recombination. Mutation of BRCA1/2 results in homologous recombination deficiency and genomic instability which drives oncogenesis and cancer proliferation. Recently, BRCA1/2 gene expression has been implicated in regulating immune response. Here we discuss the signaling pathway of BRCA1/2 in relation to breast and ovarian cancer, with emphasis on how dysregulation facilitates the path to malignancy and current treatment options.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinogênese/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Instabilidade Genômica , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Mutação , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Prognóstico , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/uso terapêutico , Reparo de DNA por Recombinação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
13.
J Cancer ; 12(1): 38-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33391401

RESUMO

While ovarian cancer typically responds well to front line treatment, many patients will relapse within 5 years. Treatment options are less effective at each recurrence highlighting the need for novel maintenance therapies. PolyADP-ribose polymerase (PARP) inhibitors have recently gained approval in ovarian cancer maintenance. Niraparib was approved regardless of BRCA mutation status, however impact on overall survival is limited. Oliparib was approved for BRCA mutant and BRCA wildtype/homologous recombination deficient patients. This review will focus on current frontline ovarian cancer treatment as well molecularly based approaches to ovarian cancer management.

14.
J Assist Reprod Genet ; 38(2): 265-276, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33389378

RESUMO

Semen analysis is the cornerstone of evaluating male infertility, but it is imperfect and insufficient to diagnose male infertility. As a result, about 20% of infertile males have undetermined infertility, a term encompassing male infertility with an unknown underlying cause. Undetermined male infertility includes two categories: (i) idiopathic male infertility-infertile males with abnormal semen analyses with an unknown cause for that abnormality and (ii) unexplained male infertility-males with "normal" semen analyses who are unable to impregnate due to unknown causes. The treatment of males with undetermined infertility is limited due to a lack of understanding the frequency of general sperm defects (e.g., number, motility, shape, viability). Furthermore, there is a lack of trusted, quantitative, and predictive diagnostic tests that look inside the sperm to quantify defects such as DNA damage, RNA abnormalities, centriole dysfunction, or reactive oxygen species to discover the underlying cause. To better treat undetermined male infertility, further research is needed on the frequency of sperm defects and reliable diagnostic tools that assess intracellular sperm components must be developed. The purpose of this review is to uniquely create a paradigm of thought regarding categories of male infertility based on intracellular and extracellular features of semen and sperm, explore the prevalence of the various categories of male factor infertility, call attention to the lack of standardization and universal application of advanced sperm testing techniques beyond semen analysis, and clarify the limitations of standard semen analysis. We also call attention to the variability in definitions and consider the benefits towards undetermined male infertility if these gaps in research are filled.


Assuntos
Infertilidade Masculina/diagnóstico , Análise do Sêmen/tendências , Motilidade dos Espermatozoides/genética , Centríolos/genética , Dano ao DNA/genética , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Masculino , Contagem de Espermatozoides , Espermatozoides/patologia , Espermatozoides/ultraestrutura
15.
Physiol Genomics ; 53(2): 51-60, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33275540

RESUMO

A novel coronavirus disease, COVID-19, has created a global pandemic in 2020, posing an enormous challenge to healthcare systems and affected communities. COVID-19 is caused by severe acute respiratory syndrome (SARS)-coronavirus-2 (CoV-2) that manifests as bronchitis, pneumonia, or a severe respiratory illness. SARS-CoV-2 infects human cells via binding a "spike" protein on its surface to angiotensin-converting enzyme 2 (ACE2) within the host. ACE2 is crucial for maintaining tissue homeostasis and negatively regulates the renin-angiotensin-aldosterone system (RAAS) in humans. The RAAS is paramount for normal function in multiple organ systems including the lungs, heart, kidney, and vasculature. Given that SARS-CoV-2 internalizes via ACE2, the resultant disruption in ACE2 expression can lead to altered tissue function and exacerbate chronic diseases. The widespread distribution and expression of ACE2 across multiple organs is critical to our understanding of the varied clinical outcomes of COVID-19. This perspective review based on the current literature was prompted to show how disruption of ACE2 by SARS-CoV-2 can affect different organ systems.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , Sistema Renina-Angiotensina/fisiologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/epidemiologia , COVID-19/virologia , Interações Hospedeiro-Patógeno , Humanos , Pandemias , Ligação Proteica , SARS-CoV-2/fisiologia , Internalização do Vírus
16.
Nat Commun ; 9(1): 2800, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30006521

RESUMO

In the original version of this Article, the affiliation details for Jadranka Loncarek and Vito Mennella were incorrectly given as 'Cell Biology Program, The Hospital for Sick Children, Department of Biochemistry, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada' and 'Laboratory of Protein Dynamics and Signaling, Center for Cancer Research, National Cancer Institute, 1050 Boyles Street, Frederick, MD, 21702, USA', respectively. This has now been corrected in both the PDF and HTML versions of the Article.

17.
Nat Commun ; 9(1): 2210, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880810

RESUMO

The inheritance of the centrosome during human fertilization remains mysterious. Here we show that the sperm centrosome contains, in addition to the known typical barrel-shaped centriole (the proximal centriole, PC), a surrounding matrix (pericentriolar material, PCM), and an atypical centriole (distal centriole, DC) composed of splayed microtubules surrounding previously undescribed rods of centriole luminal proteins. The sperm centrosome is remodeled by both reduction and enrichment of specific proteins and the formation of these rods during spermatogenesis. In vivo and in vitro investigations show that the flagellum-attached, atypical DC is capable of recruiting PCM, forming a daughter centriole, and localizing to the spindle pole during mitosis. Altogether, we show that the DC is compositionally and structurally remodeled into an atypical centriole, which functions as the zygote's second centriole. These findings now provide novel avenues for diagnostics and therapeutic strategies for male infertility, and insights into early embryo developmental defects.


Assuntos
Centríolos/fisiologia , Fertilização/fisiologia , Espermatogênese/fisiologia , Espermatozoides/citologia , Animais , Bovinos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Centríolos/ultraestrutura , Anormalidades Congênitas/etiologia , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização in vitro , Flagelos/fisiologia , Humanos , Infertilidade Masculina/etiologia , Masculino , Microscopia Eletrônica , Microtúbulos/fisiologia , Microtúbulos/ultraestrutura , Mitose/fisiologia , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Testículo/citologia , Tubulina (Proteína)/metabolismo , Xenopus laevis , Zigoto/citologia
18.
Open Biol ; 7(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28298310

RESUMO

Typical centrioles are made of microtubules organized in ninefold symmetry. Most animal somatic cells have two centrioles for normal cell division and function. These centrioles originate from the zygote, but because the oocyte does not provide any centrioles, it is surprising that the zygotes of many animals are thought to inherit only one centriole from the sperm. Recently, in the sperm of Drosophila melanogaster, we discovered a second centriolar structure, the proximal centriole-like structure (PCL), which functions in the zygote. Whether the sperm of other insects has a second centriolar structure is unknown. Here, we characterized spermiogenesis in the red flour beetle, Tribolium castaneum Electron microscopy suggests that Tribolium has one microtubule-based centriole at the tip of the axoneme and a structure similar to the PCL, which lacks microtubules and lies in a cytoplasmic invagination of the nucleus. Immunostaining against the orthologue of the centriole/PCL protein, Ana1, also recognizes two centrioles near the nucleus during spermiogenesis: one that is microtubule-based at the tip of the axoneme, suggesting it is the centriole; and another that is more proximal and appears during early spermiogenesis, suggesting it is the PCL. Together, these findings suggest that Tribolium sperm has one microtubule-based centriole and one microtubule-lacking centriole.


Assuntos
Centríolos/ultraestrutura , Microtúbulos/ultraestrutura , Espermatozoides/ultraestrutura , Tribolium/ultraestrutura , Animais , Centríolos/metabolismo , Masculino , Microtúbulos/metabolismo , Espermátides/metabolismo , Espermátides/ultraestrutura , Espermatogênese , Espermatozoides/metabolismo , Tribolium/fisiologia
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