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1.
Circulation ; 146(24): 1836-1854, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-35862223

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a well-established treatment option for high- and intermediate-risk patients with severe symptomatic aortic valve stenosis. A majority of patients exhibit improvements in left ventricular ejection fraction (LVEF) after TAVR in response to TAVR-associated afterload reduction. However, a specific role for circulating microRNAs (miRNAs) in the improvement of cardiac function for patients after TAVR has not yet been investigated. Here, we profiled the differential expression of miRNAs in circulating extracellular vesicles (EVs) in patients after TAVR and, in particular, the novel role of circulating miR-122-5p in cardiomyocytes. METHODS: Circulating EV-associated miRNAs were investigated by use of an unbiased Taqman-based human miRNA array. Several EV miRNAs (miR-122-5p, miR-26a, miR-192, miR-483-5p, miR-720, miR-885-5p, and miR-1274) were significantly deregulated in patients with aortic valve stenosis at day 7 after TAVR compared with the preprocedural levels in patients without LVEF improvement. The higher levels of miR-122-5p were negatively correlated with LVEF improvement at both day 7 (r=-0.264 and P=0.015) and 6 months (r=-0.328 and P=0.0018) after TAVR. RESULTS: Using of patient-derived samples and a murine aortic valve stenosis model, we observed that the expression of miR-122-5p correlates negatively with cardiac function, which is associated with LVEF. Mice with graded wire injury-induced aortic valve stenosis demonstrated a higher level of miR-122-5p, which was related to cardiomyocyte dysfunction. Murine ex vivo experiments revealed that miR-122-5p is highly enriched in endothelial cells compared with cardiomyocytes. Coculture experiments, copy-number analysis, and fluorescence microscopy with Cy3-labeled miR-122-5p demonstrated that miR-122-5p can be shuttled through large EVs from endothelial cells into cardiomyocytes. Gain- and loss-of-function experiments suggested that EV-mediated shuttling of miR-122-5p increases the level of miR-122-5p in recipient cardiomyocytes. Mechanistically, mass spectrometry, miRNA pulldown, electrophoretic mobility shift assay, and RNA immunoprecipitation experiments confirmed that miR-122-5p interacts with the RNA-binding protein hnRNPU (heterogeneous nuclear ribonucleoprotein U) in a sequence-specific manner to encapsulate miR-122-5p into large EVs. On shuttling, miR-122-5p reduces the expression of the antiapoptotic gene BCL2 by binding to its 3' untranslated region to inhibit its translation, thereby decreasing the viability of target cardiomyocytes. CONCLUSIONS: Increased levels of circulating proapoptotic EV-incorporated miR-122-5p are associated with reduced LVEF after TAVR. EV shuttling of miR-122-5p regulates the viability and apoptosis of cardiomyocytes in a BCL2-dependent manner.


Assuntos
Estenose da Valva Aórtica , MicroRNA Circulante , Vesículas Extracelulares , MicroRNAs , Substituição da Valva Aórtica Transcateter , Humanos , Camundongos , Animais , Substituição da Valva Aórtica Transcateter/métodos , Função Ventricular Esquerda/fisiologia , Volume Sistólico/fisiologia , Células Endoteliais , Estenose da Valva Aórtica/cirurgia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Valva Aórtica/cirurgia , Resultado do Tratamento
3.
Am J Physiol Cell Physiol ; 318(1): C1-C28, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31483703

RESUMO

Although a majority of the mammalian genome is transcribed to RNA, mounting evidence indicates that only a minor proportion of these transcriptional products are actually translated into proteins. Since the discovery of the first non-coding RNA (ncRNA) in the 1980s, the field has gone on to recognize ncRNAs as important molecular regulators of RNA activity and protein function, knowledge of which has stimulated the expansion of a scientific field that quests to understand the role of ncRNAs in cellular physiology, tissue homeostasis, and human disease. Although our knowledge of these molecules has significantly improved over the years, we have limited understanding of their precise functions, protein interacting partners, and tissue-specific activities. Adding to this complexity, it remains unknown exactly how many ncRNAs there are in existence. The increased use of high-throughput transcriptomics techniques has rapidly expanded the list of ncRNAs, which now includes classical ncRNAs (e.g., ribosomal RNAs and transfer RNAs), microRNAs, and long ncRNAs. In addition, splicing by-products of protein-coding genes and ncRNAs, so-called circular RNAs, are now being investigated. Because there is substantial heterogeneity in the functions of ncRNAs, we have summarized the present state of knowledge regarding the functions of ncRNAs in heart, lungs, and skeletal muscle. This review highlights the pathophysiologic relevance of these ncRNAs in the context of human cardiovascular, pulmonary, and muscle diseases.


Assuntos
Doenças Cardiovasculares/genética , Pneumopatias/genética , Doenças Musculares/genética , RNA não Traduzido/genética , Animais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Regulação da Expressão Gênica , Marcadores Genéticos , Humanos , Pneumopatias/diagnóstico , Pneumopatias/metabolismo , Pneumopatias/fisiopatologia , Doenças Musculares/diagnóstico , Doenças Musculares/metabolismo , Doenças Musculares/fisiopatologia , Valor Preditivo dos Testes , RNA não Traduzido/metabolismo , Transdução de Sinais
4.
Curr Opin Cardiol ; 35(3): 199-206, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32068613

RESUMO

PURPOSE OF REVIEW: Mounting evidence suggests that long noncoding RNAs (lncRNAs) are essential regulators of gene expression. Although few lncRNAs have been the subject of detailed molecular and functional characterization, it is believed that lncRNAs play an important role in tissue homeostasis and development. In fact, gene expression profiling studies reveal lncRNAs are developmentally regulated in a tissue-type and cell-type specific manner. Such findings have brought significant attention to their potential contribution to disease cause. The current review summarizes recent studies of lncRNAs in the heart. RECENT FINDINGS: lncRNA discovery has largely been driven by the implementation of next generation sequencing technologies. To date, such technologies have contributed to the identification of tens of thousands of distinct lncRNAs in humans -- accounting for a large majority of all RNA sequences transcribed across the human genome. Although the functions of these lncRNAs remain largely unknown, gain-of-function and loss-of-function studies (in vivo and in vitro) have uncovered a number of mechanisms by which lncRNAs regulate gene expression and protein function. Such mechanisms have been stratified according to three major functional categories: RNA sponges (RNA-mediated sequestration of free miRNAs; e.g. H19, MEG3, and MALAT1); transcription-modulating lncRNAs (RNA influences regulatory factor recruitment by binding to histone modifiers or transcription factors; e.g. CAIF, MANTIS, and NEAT1); and translation-modulating lncRNAs (RNA modifies protein function via directly interacting with a protein itself or binding partners; e.g. Airn, CCRR, and ZFAS1). SUMMARY: Recent studies strongly suggest that lncRNAs function via binding to macromolecules (e.g. genomic DNA, miRNAs, or proteins). Thus, lncRNAs constitute an additional mode by which cells regulate gene expression.


Assuntos
RNA Longo não Codificante/genética , Humanos
5.
Circ Res ; 122(10): 1347-1353, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29483092

RESUMO

RATIONALE: Increasing evidence indicates the presence of lncRNAs in various cell types. Airn is an imprinting gene transcribed from the paternal chromosome. It is in antisense orientation to the imprinted, but maternally derived, Igf2r gene, on which Airn exerts its regulation in cis. Although Airn is highly expressed in the heart, functions aside from imprinting remain unknown. OBJECTIVE: Here, we studied the functions of Airn in the heart, especially cardiomyocytes. METHODS AND RESULTS: Silencing of Airn via siRNAs augmented cell death, vulnerability to cellular stress, and reduced cell migration. To find the cause of such phenotypes, the potential binding partners of Airn were identified via RNA pull-down followed by mass spectrometry, which indicated Igf2bp2 (insulin-like growth factor 2 mRNA-binding protein 2) and Rpa1 (replication protein A1) as potential binding partners. Further experiments showed that Airn binds to Igf2bp2 to control the translation of several genes. Moreover, silencing of Airn caused less binding of Igf2bp2 to other mRNAs and reduced translation of Igf2bp2 protein. CONCLUSIONS: Our study uncovers a new function of Airn and demonstrates that Airn is important for the physiology of cardiomyocytes.


Assuntos
Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/biossíntese , Animais , Linhagem Celular , Movimento Celular , Regulação da Expressão Gênica , Camundongos , Infarto do Miocárdio/metabolismo , Especificidade de Órgãos , Ligação Proteica , Biossíntese de Proteínas , Interferência de RNA , Splicing de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas de Ligação a RNA/genética , Proteína de Replicação A/metabolismo
6.
Basic Res Cardiol ; 114(1): 3, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30446837

RESUMO

Preclinical investigations support the concept that donor cells more oriented towards a cardiovascular phenotype favor repair. In light of this philosophy, we previously identified HDAC1 as a mediator of cardiac mesenchymal cell (CMC) cardiomyogenic lineage commitment and paracrine signaling potency in vitro-suggesting HDAC1 as a potential therapeutically exploitable target to enhance CMC cardiac reparative capacity. In the current study, we examined the effects of pharmacologic HDAC1 inhibition, using the benzamide class 1 isoform-selective HDAC inhibitor entinostat (MS-275), on CMC cardiomyogenic lineage commitment and CMC-mediated myocardial repair in vivo. Human CMCs pre-treated with entinostat or DMSO diluent control were delivered intramyocardially in an athymic nude rat model of chronic ischemic cardiomyopathy 30 days after a reperfused myocardial infarction. Indices of cardiac function were assessed by echocardiography and left ventricular (LV) Millar conductance catheterization 35 days after treatment. Compared with naïve CMCs, entinostat-treated CMCs exhibited heightened capacity for myocyte-like differentiation in vitro and superior ability to attenuate LV remodeling and systolic dysfunction in vivo. The improvement in CMC therapeutic efficacy observed with entinostat pre-treatment was not associated with enhanced donor cell engraftment, cardiomyogenesis, or vasculogenesis, but instead with more efficient inhibition of myocardial fibrosis and greater increase in myocyte size. These results suggest that HDAC inhibition enhances the reparative capacity of CMCs, likely via a paracrine mechanism that improves ventricular compliance and contraction and augments myocyte growth and function.


Assuntos
Histona Desacetilase 1/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Benzamidas/farmacologia , Fibrose , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/metabolismo , Piridinas/farmacologia , Ratos , Ratos Nus , Recuperação de Função Fisiológica
7.
Stem Cells ; 34(12): 2916-2929, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27501845

RESUMO

Histone deacetylase (HDAC) regulation is an essential process in myogenic differentiation. Inhibitors targeting the activity of specific HDAC family members have been shown to enhance the cardiogenic differentiation capacity of discrete progenitor cell types; a key property of donor cell populations contributing to their afforded benefits in cardiac cell therapy applications. The influence of HDAC inhibition on cardiac-derived mesenchymal stromal cell (CMC) transdifferentiation or the role of specific HDAC family members in dictating cardiovascular cell lineage specification has not been investigated. In the current study, the consequences of HDAC inhibition on patient-derived CMC proliferation, cardiogenic program activation, and cardiovascular differentiation/cell lineage specification were investigated using pharmacologic and genetic targeting approaches. Here, CMCs exposed to the pan-HDAC inhibitor sodium butyrate exhibited induction of a cardiogenic transcriptional program and heightened expression of myocyte and endothelial lineage-specific markers when coaxed to differentiate in vitro. Further, shRNA knockdown screens revealed CMCs depleted of HDAC1 to promote the induction of a cardiogenic transcriptional program characterized by enhanced expression of cardiomyogenic- and vasculogenic-specific markers, a finding which depended on and correlated with enhanced acetylation and stabilization of p53. Cardiogenic gene activation and elevated p53 expression levels observed in HDAC1-depleted CMCs were associated with improved aptitude to assume a cardiomyogenic/vasculogenic cell-like fate in vitro. These results suggest that HDAC1 depletion-induced p53 expression alters CMC cell fate decisions and identify HDAC1 as a potential exploitable target to facilitate CMC-mediated myocardial repair in ischemic cardiomyopathy. Stem Cells 2016;34:2916-2929.


Assuntos
Epigênese Genética , Histona Desacetilase 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Biomarcadores/metabolismo , Ácido Butírico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HEK293 , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Transcrição Gênica/efeitos dos fármacos
9.
Basic Res Cardiol ; 110(5): 503, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26150250

RESUMO

It is commonly thought that the optimal method for intracoronary administration of cells is to stop coronary flow during cell infusion, in order to prolong cell/vascular wall contact, enhance adhesion, and promote extravasation of cells into the interstitial space. However, occlusion of a coronary artery with a balloon involves serious risks of vascular damage and/or dissection, particularly in non-stented segments such as those commonly found in patients with heart failure. It remains unknown whether the use of the stop-flow technique results in improved donor cell retention. Acute myocardial infarction was produced in 14 pigs. One to two months later, pigs received 10 million indium-111 oxyquinoline (oxine)-labeled c-kit(pos) human cardiac stem cells (hCSCs) via intracoronary infusion with (n = 7) or without (n = 7) balloon inflation. Pigs received cyclosporine to prevent acute graft rejection. Animals were euthanized 24 h later and hearts harvested for radioactivity measurements. With the stop-flow technique, the retention of hCSCs at 24 h was 5.41 ± 0.80 % of the injected dose (n = 7), compared with 4.87 ± 0.62 % without coronary occlusion (n = 7), (P = 0.60). When cells are delivered intracoronarily in a clinically relevant porcine model of chronic ischemic cardiomyopathy, the use of the stop-flow technique does not result in greater myocardial cell retention at 24 h compared with non-occlusive infusion. These results have practical implications for the design of cell therapy trials. Our observations suggest that the increased risk of complications secondary to coronary manipulation and occlusion is not warranted.


Assuntos
Isquemia Miocárdica/cirurgia , Miócitos Cardíacos/transplante , Transplante de Células-Tronco/métodos , Animais , Separação Celular , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Proteínas Proto-Oncogênicas c-kit , Sus scrofa
10.
Catheter Cardiovasc Interv ; 85(1): 118-29, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25204308

RESUMO

BACKGROUND: Data are limited regarding transcatheter aortic valve replacement (TAVR)-related thrombocytopenia (TP). We sought to thoroughly characterize the presence, clinical impact, and severity of TP associated with TAVR. METHODS AND RESULTS: Data were collected from 90 patients who underwent TAVR using the Edwards SAPIEN valve (59 TF, 29 TA, 2 Tao). Platelet counts were evaluated peri-procedurally and for 8 days following TAVR. Platelet levels were compared and patients were divided into a no TP (No-TP) group 1, acquired (new) TP (NTP) group 2, pre-existing (pre-TAVR) TP (PTP) group 3, and further stratified based on the severity of TP: mild (M) TP (100-149 × 10(3) cell/µL) and moderate-severe (MS) TP (<100 × 10(3) cell/µL). Pre-TAVR point prevalence and post-TAVR incidence of TP were 40% and 79%, respectively (P < 0.001); nadir platelet count in all groups occurred day 4 post-TAVR. Baseline predictors for developing MS TP in groups 2-3 included baseline TP, leaner body mass, smaller pre-procedural aortic valve area, higher peak aortic jet velocity, and worsening baseline renal function. Development of "major" TP (nadir platelet count <100 × 103 cell/µL, ≥50% decrease) predicted a higher risk of major vascular complications (OR 2.78 [95% CI, 1.58-3.82]) and major bleeding (OR 3.18 [95% CI, 1.33-5.42]) in group 3. CONCLUSION: TAVR-related TP is predictable and classification by PTP and TP severity prior to TAVR allows for better risk stratification in predicting in-hospital clinical outcomes. Major TP in the presence of worsening TP is predictable and is associated with worse clinical outcomes. © 2014 Wiley Periodicals, Inc.


Assuntos
Estenose da Valva Aórtica/terapia , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Implante de Prótese de Valva Cardíaca/efeitos adversos , Trombocitopenia/etiologia , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/métodos , Distribuição de Qui-Quadrado , Feminino , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Kentucky , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Contagem de Plaquetas , Valor Preditivo dos Testes , Desenho de Prótese , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Trombocitopenia/sangue , Trombocitopenia/diagnóstico , Fatores de Tempo , Resultado do Tratamento
11.
Biochem Biophys Res Commun ; 437(1): 29-34, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23792098

RESUMO

Shwachman Diamond syndrome (SDS) is an inherited bone marrow failure syndrome typically characterized by neutropenia, exocrine pancreas dysfunction, metaphyseal chondrodysplasia, and predisposition to myelodysplastic syndrome and leukemia. SBDS, the gene affected in most cases of SDS, encodes a protein known to influence many cellular processes including ribosome biogenesis, mitotic spindle assembly, chemotaxis, and the regulation of reactive oxygen species production. The best characterized role for the SBDS protein is in the production of functional 60S ribosomal subunits. Given that a reduction in functional 60S subunits could impact on the translational output of cells depleted of SBDS we analyzed protein synthesis in yeast cells lacking SDO1, the ortholog of SBDS. Cells lacking SDO1 selectively increased the synthesis of POR1, the ortholog of mammalian VDAC1 a major anion channel of the mitochondrial outer membrane. Further studies revealed the cells lacking SDO1 were compromised in growth on non-fermentable carbon sources suggesting mitochondrial function was impaired. These observations prompted us to examine mitochondrial function in human cells where SBDS expression was reduced. Our studies indicate that reduced expression of SBDS decreases mitochondrial membrane potential and oxygen consumption and increases the production of reactive oxygen species. These studies indicate that mitochondrial function is also perturbed in cells expressing reduced amounts of SBDS and indicate that disruption of mitochondrial function may also contribute to SDS pathophysiology.


Assuntos
Doenças da Medula Óssea/metabolismo , Doenças da Medula Óssea/patologia , Insuficiência Pancreática Exócrina/metabolismo , Insuficiência Pancreática Exócrina/patologia , Lipomatose/metabolismo , Lipomatose/patologia , Mitocôndrias/metabolismo , Modelos Biológicos , Saccharomyces cerevisiae/metabolismo , Carbono/farmacologia , Linhagem Celular , Fermentação/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Proteínas/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/metabolismo , Síndrome de Shwachman-Diamond
13.
Front Cardiovasc Med ; 9: 913612, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845053

RESUMO

Scientific advancement is predicated upon the ability of a novel discovery to be independently reproduced and substantiated by others. Despite this inherent necessity, the research community is awash in published studies that cannot be replicated resulting in widespread confusion within the field and waning trust from the general public. In many cases, irreproducibility is the unavoidable consequence of a study that is conducted without the appropriate degree of rigor, typified by fundamental flaws in approach, design, execution, analysis, interpretation, and reporting. Combatting the irreproducibility pandemic in preclinical research is of urgent concern and is the primary responsibility of individual investigators, however there are important roles to be played by institutions, journals, government entities, and funding agencies as well. Herein, we provide an updated review of established rigor criteria pertaining to both in vitro and in vivo studies compiled from multiple sources across the research enterprise and present a practical checklist as a straightforward reference guide. It is our hope that this review may serve as an approachable resource for early career and experienced investigators alike, as they strive to improve all aspects of their scientific endeavors.

14.
Cells ; 11(14)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35883673

RESUMO

Excitable cells of the nervous and cardiovascular systems depend on an assortment of plasmalemmal potassium channels to control diverse cellular functions. Voltage-gated potassium (Kv) channels are central to the feedback control of membrane excitability in these processes due to their activation by depolarized membrane potentials permitting K+ efflux. Accordingly, Kv currents are differentially controlled not only by numerous cellular signaling paradigms that influence channel abundance and shape voltage sensitivity, but also by heteromeric configurations of channel complexes. In this context, we discuss the current knowledge related to how intracellular Kvß proteins interacting with pore complexes of Shaker-related Kv1 channels may establish a modifiable link between excitability and metabolic state. Past studies in heterologous systems have indicated roles for Kvß proteins in regulating channel stability, trafficking, subcellular targeting, and gating. More recent works identifying potential in vivo physiologic roles are considered in light of these earlier studies and key gaps in knowledge to be addressed by future research are described.


Assuntos
Canais de Potássio de Abertura Dependente da Tensão da Membrana , Potássio , Membrana Celular/metabolismo , Potenciais da Membrana/fisiologia , Potássio/metabolismo , Canais de Potássio/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo
15.
Matrix Biol ; 109: 49-69, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35346795

RESUMO

The cardiac extracellular matrix plays essential roles in homeostasis and injury responses. Although the role of fibrillar collagens have been thoroughly documented, the functions of non-fibrillar collagen members remain underexplored. These include a distinct group of non-fibrillar collagens, termed, fibril-associated collagens with interrupted triple helices (FACITs). Recent reports of collagen type XIX (encoded by Col19a1) expression in adult heart and evidence of its enhanced expression in cardiac ischemia suggest important functions for this FACIT in cardiac ECM structure and function. Here, we examined the cellular source of collagen XIX in the adult murine heart and evaluated its involvement in ECM structure and ventricular function. Immunodetection of collagen XIX in fractionated cardiovascular cell lineages revealed fibroblasts and smooth muscle cells as the primary sources of collagen XIX in the heart. Based on echocardiographic and histologic analyses, Col19a1 null (Col19a1N/N) mice exhibited reduced systolic function, thinning of left ventricular walls, and increased cardiomyocyte cross-sectional areas-without gross changes in myocardial collagen content or basement membrane morphology. Col19a1N/N cardiac fibroblasts had augmented expression of several enzymes involved in the synthesis and stability of fibrillar collagens, including PLOD1 and LOX. Furthermore, second harmonic generation-imaged ECM derived from Col19a1N/N cardiac fibroblasts, and transmission electron micrographs of decellularized hearts from Col19a1N/N null animals, showed marked reductions in fibrillar collagen structural organization. Col19a1N/N mice also displayed enhanced phosphorylation of focal adhesion kinase (FAK), signifying de-repression of the FAK pathway-a critical mediator of cardiomyocyte hypertrophy. Collectively, we show that collagen XIX, which had a heretofore unknown role in the mammalian heart, participates in the regulation of cardiac structure and function-potentially through modulation of ECM fibrillar collagen structural organization. Further, these data suggest that this FACIT may modify ECM superstructure via acting at the level of the fibroblast to regulate their expression of collagen synthetic and stabilization enzymes.


Assuntos
Colágeno , Colágenos Associados a Fibrilas , Animais , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Colágenos Associados a Fibrilas/metabolismo , Colágenos Fibrilares/metabolismo , Mamíferos/metabolismo , Camundongos , Função Ventricular
16.
Food Environ Virol ; 14(4): 410-416, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35982363

RESUMO

This study aimed to develop a framework for combining community wastewater surveillance with state clinical surveillance for the confirmation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants within the community and to provide recommendations on how to expand on such research and apply the findings in public health responses. Wastewater samples were collected weekly from 17 geographically resolved locations in Louisville/Jefferson County, Kentucky (USA), from February 10 to December 13, 2021. Genomic surveillance and quantitative reverse transcription PCR (RT-qPCR) platforms were used to screen for SARS-CoV-2 in wastewater, and state clinical surveillance was used for confirmation. The study results highlighted an increased epidemiological value of combining community wastewater genomic surveillance and RT-qPCR with conventional case-auditing methods. The spatial scale and temporal frequency of wastewater sampling provided promising sensitivity and specificity for gaining public health screening insights about SARS-CoV-2 emergence, seeding, and spread in communities. Improved national surveillance systems are needed against future pathogens and variants, and wastewater-based genomic surveillance exhibits great potential when coupled with clinical testing. This paper presents evidence that complementary wastewater and clinical testing are cost-effectively enhanced when used in combination, as they provide a strong tool for a joint public health framework. Future pathogens of interest may be examined in either a targeted fashion or using a more global approach where all pathogens are monitored. This study has also provided novel insights developed from evidence-based public health practices.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Águas Residuárias , COVID-19/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias , Genômica , Prática de Saúde Pública
17.
Pathogens ; 11(11)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36365000

RESUMO

Despite entering an endemic phase, SARS-CoV-2 remains a significant burden to public health across the global community. Wastewater sampling has consistently proven utility to understanding SARS-CoV-2 prevalence trends and genetic variation as it represents a less biased assessment of the corresponding communities. Here, we report that ongoing monitoring of SARS-CoV-2 genetic variation in samples obtained from the wastewatersheds of the city of Louisville in Jefferson county Kentucky has revealed the periodic reemergence of the Delta strain in the presence of the presumed dominant Omicron strain. Unlike previous SARS-CoV-2 waves/emergence events, the Delta reemergence events were geographically restricted in the community and failed to spread into other areas as determined by wastewater analyses. Moreover, the reemergence of the Delta strain did not correlate with vaccination rates as communities with lower relative vaccination have been, to date, not affected. Importantly, Delta reemergence events correlate with increased public health burdens, as indicated by increased daily case rates and mortality relative to non-Delta wastewatershed communities. While the underlying reasons for the reemergence of the Delta variant remain unclear, these data reaffirm the ongoing importance of wastewater genomic analyses towards understanding SARS-CoV-2 as it enters the endemic phase.

18.
Nat Commun ; 13(1): 2051, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440632

RESUMO

Adequate oxygen delivery to the heart during stress is essential for sustaining cardiac function. Acute increases in myocardial oxygen demand evoke coronary vasodilation and enhance perfusion via functional upregulation of smooth muscle voltage-gated K+ (Kv) channels. Because this response is controlled by Kv1 accessory subunits (i.e., Kvß), which are NAD(P)(H)-dependent aldo-keto reductases, we tested the hypothesis that oxygen demand modifies arterial [NAD(H)]i, and that resultant cytosolic pyridine nucleotide redox state influences Kv1 activity. High-resolution imaging mass spectrometry and live-cell imaging reveal cardiac workload-dependent increases in NADH:NAD+ in intramyocardial arterial myocytes. Intracellular NAD(P)(H) redox ratios reflecting elevated oxygen demand potentiate native coronary Kv1 activity in a Kvß2-dependent manner. Ablation of Kvß2 catalysis suppresses redox-dependent increases in Kv1 activity, vasodilation, and the relationship between cardiac workload and myocardial blood flow. Collectively, this work suggests that the pyridine nucleotide sensitivity and enzymatic activity of Kvß2 controls coronary vasoreactivity and myocardial blood flow during metabolic stress.


Assuntos
NAD , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Músculo Liso , Nucleotídeos , Oxirredução , Oxigênio , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Piridinas
19.
Haematologica ; 95(1): 57-64, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19713223

RESUMO

BACKGROUND: Diamond-Blackfan anemia and Shwachman-Diamond syndrome are inherited bone marrow failure syndromes linked to defects in ribosome synthesis. The purpose of this study was to determine whether yeast models for Diamond-Blackfan anemia and Shwachman-Diamond syndrome differed in the mechanism by which ribosome synthesis was affected. DESIGN AND METHODS: Northern blotting, pulse-chase analysis, and polysome profiling were used to study ribosome synthesis in yeast models. Localization of 60S ribosomal subunits was assessed using RPL25eGFP. RESULTS: Relative to wild-type controls, each disease model showed defects in 60S subunit maturation, but with distinct underlying mechanisms. In the model of Diamond-Blackfan anemia, 60S subunit maturation was disrupted at a relatively early stage with abortive complexes subject to rapid degradation. 5S ribosomal RNA, unlike other large subunit ribosomal RNA in this model, accumulated as an extra-ribosomal species. In contrast, subunit maturation in the Shwachman-Diamond syndrome model was affected at a later step, giving rise to relatively stable pre-60S particles with associated 5S ribosomal RNA retained in the nucleus. Conclusions These differences between the yeast Diamond-Blackfan anemia and Shwachman-Diamond syndrome models have implications for signaling mechanisms linking abortive ribosome assembly to cell fate decisions and may contribute to the divergent clinical presentations of Diamond-Blackfan anemia and Shwachman-Diamond syndrome.


Assuntos
Anemia de Diamond-Blackfan/genética , Modelos Biológicos , Ribossomos/genética , Proteínas de Saccharomyces cerevisiae/genética , Anemia de Diamond-Blackfan/metabolismo , Anemia de Diamond-Blackfan/patologia , Animais , Modelos Animais de Doenças , Humanos , Mutação , Proteínas Ribossômicas/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Ribossomos/patologia , Proteínas de Saccharomyces cerevisiae/biossíntese
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