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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2487-2490, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018511

RESUMO

Cardiac cellular models are utilized as the building blocks for tissue simulation. One of the imprecisions of conventional cellular modeling, especially when the models are used in tissue-level modeling, stems from the mere consideration of cellular properties (e.g., action potential shape) in parameter tuning of the model. In our previous work, we put forward an accurate framework in which membrane resistance (Rm) reflecting inter-cellular characteristics, i.e., electrotonic effects, was considered alongside cellular features in cellular model fitting. This paper, for the first time, examines the hypothesis that considering Rm as an additional optimization objective improves the accuracy of tissue-level modeling. To study this hypothesis, after cellular-level optimization of a well-known model, source-sink mismatch configurations in a 2-dimensional model are investigated. The results demonstrate that including Rm in the optimization protocol yields a substantial improvement in the relative error of the critical transition border which is defined as the minimum window size between source and sink that wave propagates. Model developers can utilize the proposed concept during parameter tuning to increase the accuracy of models.


Assuntos
Potenciais de Ação , Coração , Coração/fisiologia , Humanos , Membranas , Miocárdio/citologia
2.
Nat Commun ; 11(1): 3953, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769974

RESUMO

Many important cell types in adult vertebrates have a mesenchymal origin, including fibroblasts and vascular mural cells. Although their biological importance is undisputed, the level of mesenchymal cell heterogeneity within and between organs, while appreciated, has not been analyzed in detail. Here, we compare single-cell transcriptional profiles of fibroblasts and vascular mural cells across four murine muscular organs: heart, skeletal muscle, intestine and bladder. We reveal gene expression signatures that demarcate fibroblasts from mural cells and provide molecular signatures for cell subtype identification. We observe striking inter- and intra-organ heterogeneity amongst the fibroblasts, primarily reflecting differences in the expression of extracellular matrix components. Fibroblast subtypes localize to discrete anatomical positions offering novel predictions about physiological function(s) and regulatory signaling circuits. Our data shed new light on the diversity of poorly defined classes of cells and provide a foundation for improved understanding of their roles in physiological and pathological processes.


Assuntos
Diferenciação Celular , Fibroblastos/fisiologia , Células-Tronco Mesenquimais/fisiologia , Miócitos de Músculo Liso/fisiologia , Pericitos/fisiologia , Animais , Separação Celular , Vasos Coronários/citologia , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Citometria de Fluxo , Intestinos/irrigação sanguínea , Intestinos/citologia , Masculino , Camundongos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/citologia , Músculo Liso Vascular/citologia , Miocárdio/citologia , Miócitos de Músculo Liso/citologia , Pericitos/citologia , RNA-Seq , Análise de Célula Única , Bexiga Urinária/irrigação sanguínea , Bexiga Urinária/citologia
3.
Nature ; 584(7822): 589-594, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32814899

RESUMO

The inner surfaces of the human heart are covered by a complex network of muscular strands that is thought to be a remnant of embryonic development1,2. The function of these trabeculae in adults and their genetic architecture are unknown. Here we performed a genome-wide association study to investigate image-derived phenotypes of trabeculae using the fractal analysis of trabecular morphology in 18,096 participants of the UK Biobank. We identified 16 significant loci that contain genes associated with haemodynamic phenotypes and regulation of cytoskeletal arborization3,4. Using biomechanical simulations and observational data from human participants, we demonstrate that trabecular morphology is an important determinant of cardiac performance. Through genetic association studies with cardiac disease phenotypes and Mendelian randomization, we find a causal relationship between trabecular morphology and risk of cardiovascular disease. These findings suggest a previously unknown role for myocardial trabeculae in the function of the adult heart, identify conserved pathways that regulate structural complexity and reveal the influence of the myocardial trabeculae on susceptibility to cardiovascular disease.


Assuntos
Doenças Cardiovasculares/genética , Fractais , Predisposição Genética para Doença , Coração/anatomia & histologia , Coração/fisiologia , Miocárdio/metabolismo , Adulto , Idoso , Animais , Doenças Cardiovasculares/fisiopatologia , Citoesqueleto/genética , Citoesqueleto/fisiologia , Técnicas de Inativação de Genes , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Coração/embriologia , Hemodinâmica , Humanos , Pessoa de Meia-Idade , Miocárdio/citologia , Oryzias/embriologia , Oryzias/genética , Fenótipo
4.
Nat Commun ; 11(1): 3133, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561764

RESUMO

Proximity proteomics has greatly advanced the analysis of native protein complexes and subcellular structures in culture, but has not been amenable to study development and disease in vivo. Here, we have generated a knock-in mouse with the biotin ligase (BioID) inserted at titin's Z-disc region to identify protein networks that connect the sarcomere to signal transduction and metabolism. Our census of the sarcomeric proteome from neonatal to adult heart and quadriceps reveals how perinatal signaling, protein homeostasis and the shift to adult energy metabolism shape the properties of striated muscle cells. Mapping biotinylation sites to sarcomere structures refines our understanding of myofilament dynamics and supports the hypothesis that myosin filaments penetrate Z-discs to dampen contraction. Extending this proof of concept study to BioID fusion proteins generated with Crispr/CAS9 in animal models recapitulating human pathology will facilitate the future analysis of molecular machines and signaling hubs in physiological, pharmacological, and disease context.


Assuntos
Carbono-Nitrogênio Ligases/genética , Proteínas de Escherichia coli/genética , Proteínas Quinases/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Proteínas Repressoras/genética , Sarcômeros/metabolismo , Animais , Animais Recém-Nascidos , Biotinilação/genética , Feminino , Técnicas de Introdução de Genes , Masculino , Redes e Vias Metabólicas , Camundongos Transgênicos , Modelos Animais , Miocárdio/citologia , Miocárdio/metabolismo , Estudo de Prova de Conceito , Mapas de Interação de Proteínas/fisiologia , Proteínas Quinases/genética , Proteostase/fisiologia , Músculo Quadríceps/citologia , Músculo Quadríceps/metabolismo , Sarcômeros/genética , Transdução de Sinais/fisiologia , Relação Estrutura-Atividade
5.
Nature ; 582(7811): 271-276, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32499640

RESUMO

A major factor in the progression to heart failure in humans is the inability of the adult heart to repair itself after injury. We recently demonstrated that the early postnatal mammalian heart is capable of regeneration following injury through proliferation of preexisting cardiomyocytes1,2 and that Meis1, a three amino acid loop extension (TALE) family homeodomain transcription factor, translocates to cardiomyocyte nuclei shortly after birth and mediates postnatal cell cycle arrest3. Here we report that Hoxb13 acts as a cofactor of Meis1 in postnatal cardiomyocytes. Cardiomyocyte-specific deletion of Hoxb13 can extend the postnatal window of cardiomyocyte proliferation and reactivate the cardiomyocyte cell cycle in the adult heart. Moreover, adult Meis1-Hoxb13 double-knockout hearts display widespread cardiomyocyte mitosis, sarcomere disassembly and improved left ventricular systolic function following myocardial infarction, as demonstrated by echocardiography and magnetic resonance imaging. Chromatin immunoprecipitation with sequencing demonstrates that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and cell cycle. Finally, we show that the calcium-activated protein phosphatase calcineurin dephosphorylates Hoxb13 at serine-204, resulting in its nuclear localization and cell cycle arrest. These results demonstrate that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and proliferation and provide mechanistic insights into the link between hyperplastic and hypertrophic growth of cardiomyocytes.


Assuntos
Calcineurina/metabolismo , Proliferação de Células , Proteínas de Homeodomínio/metabolismo , Proteína Meis1/metabolismo , Miócitos Cardíacos/citologia , Animais , Animais Recém-Nascidos , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Coração/fisiologia , Proteínas de Homeodomínio/genética , Masculino , Camundongos , Miocárdio/citologia , Ligação Proteica , Regeneração
6.
Basic Res Cardiol ; 115(4): 36, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: covidwho-245247

RESUMO

There are no definitive therapies for patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Therefore, new therapeutic strategies are needed to improve clinical outcomes, particularly in patients with severe disease. This case series explores the safety and effectiveness of intravenous allogeneic cardiosphere-derived cells (CDCs), formulated as CAP-1002, in critically ill patients with confirmed coronavirus disease 2019 (COVID-19). Adverse reactions to CAP-1002, clinical status on the World Health Organization (WHO) ordinal scale, and changes in pro-inflammatory biomarkers and leukocyte counts were analyzed. All patients (n = 6; age range 19-75 years, 1 female) required ventilatory support (invasive mechanical ventilation, n = 5) with PaO2/FiO2 ranging from 69 to 198. No adverse events related to CAP-1002 administration were observed. Four patients (67%) were weaned from respiratory support and discharged from the hospital. One patient remains mechanically ventilated as of April 28th, 2020; all survive. A contemporaneous control group of critically ill COVID-19 patients (n = 34) at our institution showed 18% overall mortality at a similar stage of hospitalization. Ferritin was elevated in all patients at baseline (range of all patients 605.43-2991.52 ng/ml) and decreased in 5/6 patients (range of all patients 252.89-1029.90 ng/ml). Absolute lymphocyte counts were low in 5/6 patients at baseline (range 0.26-0.82 × 103/µl) but had increased in three of these five patients at last follow-up (range 0.23-1.02 × 103/µl). In this series of six critically ill COVID-19 patients, intravenous infusion of CAP-1002 was well tolerated and associated with resolution of critical illness in 4 patients. This series demonstrates the apparent safety of CAP-1002 in COVID-19. While this initial experience is promising, efficacy will need to be further assessed in a randomized controlled trial.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Ensaios de Uso Compassivo , Infecções por Coronavirus/terapia , Miocárdio/citologia , Pneumonia Viral/terapia , Células-Tronco/citologia , Idoso , Betacoronavirus , Biomarcadores/sangue , Estado Terminal/terapia , Feminino , Ferritinas/sangue , Humanos , Infusões Intravenosas , Los Angeles , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Adulto Jovem
7.
Am J Physiol Heart Circ Physiol ; 319(1): H235-H241, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32469635

RESUMO

To maximize data obtainment from valuable cardiac tissue, we hypothesized that myocardium fixed in optimal cutting temperature (OCT) medium for histology could also be used to investigate the function of myofilament proteins in situ. We compared tissue prepared via conventional liquid nitrogen (LN) snap freezing with tissue fixed in OCT and then sectioned in fiber-parallel orientation. We found that actin-myosin Ca2+ sensitivity, activation rate by Ca2+, cooperativity along the thin filament, as well as cross-bridge cycling rate were unaffected by OCT storage and could reliably be interpreted after sectioning. Absolute values in maximum force generation per cross-sectional area, as well as passive strain, are difficult to investigate after sectioning, as myofibrillar continuity along the preparation cannot be guaranteed. We have shown that myocardial tissue stored in OCT and sectioned before analysis is available for functional analysis, a valuable means of maximizing usage of precious cardiac biopsies.NEW & NOTEWORTHY Myocardial tissue in optimal cutting temperature (OCT) fixation and cryostat sectioning was tested as a means of storing and preparing tissue for myofilament function analysis in relation to conventional liquid nitrogen freezing and dissection. Actomyosin interaction, Ca2+ force activation, and passive compliance were tested. The study concluded that OCT storage and cryostat sectioning do not interfere with the actomyosin cross-bridge dynamics or Ca2+ activation but that absolute tension values suffer and may not be investigated by this method.


Assuntos
Criopreservação/métodos , Secções Congeladas/métodos , Miocárdio/citologia , Miofibrilas/metabolismo , Inclusão em Parafina/métodos , Animais , Criopreservação/normas , Secções Congeladas/normas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miofibrilas/ultraestrutura , Inclusão em Parafina/normas
8.
Basic Res Cardiol ; 115(4): 36, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32399655

RESUMO

There are no definitive therapies for patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Therefore, new therapeutic strategies are needed to improve clinical outcomes, particularly in patients with severe disease. This case series explores the safety and effectiveness of intravenous allogeneic cardiosphere-derived cells (CDCs), formulated as CAP-1002, in critically ill patients with confirmed coronavirus disease 2019 (COVID-19). Adverse reactions to CAP-1002, clinical status on the World Health Organization (WHO) ordinal scale, and changes in pro-inflammatory biomarkers and leukocyte counts were analyzed. All patients (n = 6; age range 19-75 years, 1 female) required ventilatory support (invasive mechanical ventilation, n = 5) with PaO2/FiO2 ranging from 69 to 198. No adverse events related to CAP-1002 administration were observed. Four patients (67%) were weaned from respiratory support and discharged from the hospital. One patient remains mechanically ventilated as of April 28th, 2020; all survive. A contemporaneous control group of critically ill COVID-19 patients (n = 34) at our institution showed 18% overall mortality at a similar stage of hospitalization. Ferritin was elevated in all patients at baseline (range of all patients 605.43-2991.52 ng/ml) and decreased in 5/6 patients (range of all patients 252.89-1029.90 ng/ml). Absolute lymphocyte counts were low in 5/6 patients at baseline (range 0.26-0.82 × 103/µl) but had increased in three of these five patients at last follow-up (range 0.23-1.02 × 103/µl). In this series of six critically ill COVID-19 patients, intravenous infusion of CAP-1002 was well tolerated and associated with resolution of critical illness in 4 patients. This series demonstrates the apparent safety of CAP-1002 in COVID-19. While this initial experience is promising, efficacy will need to be further assessed in a randomized controlled trial.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Ensaios de Uso Compassivo , Infecções por Coronavirus/terapia , Miocárdio/citologia , Pneumonia Viral/terapia , Células-Tronco/citologia , Idoso , Betacoronavirus , Biomarcadores/sangue , Estado Terminal/terapia , Feminino , Ferritinas/sangue , Humanos , Infusões Intravenosas , Los Angeles , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Adulto Jovem
9.
J Vis Exp ; (159)2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32449726

RESUMO

Afterload is known to drive the development of both physiological and pathological cardiac states. As such, studying the outcomes of altered afterload states could yield important insights into the mechanisms controlling these critical processes. However, an experimental technique for precisely fine-tuning afterload in heart tissue over time is currently lacking. Here, a newly developed magnetics-based technique for achieving this control in engineered heart tissues (EHTs) is described. In order to produce magnetically responsive EHTs (MR-EHTs), the tissues are mounted on hollow silicone posts, some of which contain small permanent magnets. A second set of permanent magnets is press-fit into an acrylic plate such that they are oriented with the same polarity and are axially-aligned with the post magnets. To adjust afterload, this plate of magnets is translated toward (higher afterload) or away (lower afterload) from the post magnets using a piezoelectric stage fitted with an encoder. The motion control software used to adjust stage positioning allows for the development of user-defined afterload regimens while the encoder ensures that the stage corrects for any inconsistencies in its location. This work describes the fabrication, calibration, and implementation of this system to enable the development of similar platforms in other labs around the world. Representative results from two separate experiments are included to exemplify the range of different studies that can be performed using this system.


Assuntos
Coração/fisiologia , Fenômenos Magnéticos , Miocárdio/citologia , Pressão , Engenharia Tecidual , Movimento
10.
J Vis Exp ; (159)2020 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-32449745

RESUMO

The isolation of ventricular cardiac myocytes from animal and human hearts is a fundamental method in cardiac research. Animal cardiomyocytes are commonly isolated by coronary perfusion with digestive enzymes. However, isolating human cardiomyocytes is challenging because human myocardial specimens usually do not allow for coronary perfusion, and alternative isolation protocols result in poor yields of viable cells. In addition, human myocardial specimens are rare and only regularly available at institutions with on-site cardiac surgery. This hampers the translation of findings from animal to human cardiomyocytes. Described here is a reliable protocol that enables efficient isolation of ventricular myocytes from human and animal myocardium. To increase the surface-to-volume ratio while minimizing cell damage, myocardial tissue slices 300 µm thick are generated from myocardial specimens with a vibratome. Tissue slices are then digested with protease and collagenase. Rat myocardium was used to establish the protocol and quantify yields of viable, calcium-tolerant myocytes by flow-cytometric cell counting. Comparison with the commonly used tissue-chunk method showed significantly higher yields of rod-shaped cardiomyocytes (41.5 ± 11.9 vs. 7.89 ± 3.6%, p < 0.05). The protocol was translated to failing and non-failing human myocardium, where yields were similar as in rat myocardium and, again, markedly higher than with the tissue-chunk method (45.0 ± 15.0 vs. 6.87 ± 5.23 cells/mg, p < 0.05). Notably, with the protocol presented it is possible to isolate reasonable numbers of viable human cardiomyocytes (9-200 cells/mg) from minimal amounts of tissue (<50 mg). Thus, the method is applicable to healthy and failing myocardium from both human and animal hearts. Furthermore, it is possible to isolate excitable and contractile myocytes from human tissue specimens stored for up to 36 h in cold cardioplegic solution, rendering the method particularly useful for laboratories at institutions without on-site cardiac surgery.


Assuntos
Separação Celular/métodos , Ventrículos do Coração/citologia , Miocárdio/citologia , Miócitos Cardíacos/citologia , Potenciais de Ação , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Sobrevivência Celular , Feminino , Humanos , Perfusão , Ratos Wistar , Reprodutibilidade dos Testes
14.
Adv Exp Med Biol ; 1229: 163-180, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285411

RESUMO

Cardiovascular disease is a leading cause of death worldwide, and with the dramatically increasing numbers of heart failure patients in the next 10 years, mortality will only increase [1]. For patients with end-stage heart failure, heart transplantation is the sole option. Regrettably, the number of available donor hearts is drastically lower than the number of patients waiting for heart transplantation. Despite evidence of cardiomyocyte renewal in adult human hearts, regeneration of functional myocardium after injury can be neglected. The limited regenerative capacity due to inadequate proliferation of existing cardiomyocytes is insufficient to repopulate areas of lost myocardium [2]. As a solution, the hypothesis that adult stem cells could be employed to generate functional cardiomyocytes was proposed. One of the early studies that supported this hypothesis involved direct injection of hematopoietic c-kit-positive cells derived from bone marrow into the infarcted heart [3]. However, in sharp contrast, more recent evidence emerged demonstrating that these hematopoietic stem cells only differentiate into cells down the hematopoietic lineage rather than into cardiomyocytes [4, 5], and the focus shifted towards stem cells residing in the heart, called cardiac progenitor cells. These CPCs were extracted and injected into the myocardium to regenerate the heart [6]. In recent years, over 80 pre-clinical studies employing cardiac stem cells in vivo in large and small animals to evaluate the effect on functional parameters were systematically reviewed, identifying differences between large and small animals [7]. Despite the positive outcome of these stem cell therapies on functional parameters, c-kit-positive cardiac progenitor cells were shown to contribute minimally to the generation of functional cardiomyocytes [8, 9]. This heavily debated topic is summarized concisely by van Berlo and Molkentin [10]. Recently, single-cell sequencing and genetic lineage tracing of proliferative cells in the murine heart in both homeostatic and regenerating conditions did not yield a quiescent cardiac stem cell population or other cell types that support transdifferentiation into cardiomyocytes, nor did it support proliferation of cardiac myocytes [11, 12]. Now, the focus is shifting towards exploiting the limited regenerative capacity of the cardiomyocytes themselves, by re-activating proliferation of existing cardiomyocytes through dedifferentiation, reentry into the cell cycle, and cytokinesis. This process is the new focus of research to promote cardiac regeneration, and can be controlled on multiple levels, including cell-cycle manipulation, reprogramming, small molecules, extra-cellular matrix (ECM), proteins, and RNA regulation [13].


Assuntos
Miocárdio/citologia , Miócitos Cardíacos/citologia , RNA não Traduzido , Regeneração/genética , Animais , Diferenciação Celular , Humanos , Miócitos Cardíacos/transplante , Transplante de Células-Tronco
15.
Adv Exp Med Biol ; 1229: 197-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285413

RESUMO

Cardiac development in the human embryo is characterized by the interactions of several transcription and growth factors leading the heart from a primordial linear tube into a synchronous contractile four-chamber organ. Studies on cardiogenesis showed that cell proliferation, differentiation, fate specification and morphogenesis are spatiotemporally coordinated by cell-cell interactions and intracellular signalling cross-talks. In recent years, research has focused on a class of inter- and intra-cellular modulators called non-coding RNAs (ncRNAs), transcribed from the noncoding portion of the DNA and involved in the proper formation of the heart. In this chapter, we will summarize the current state of the art on the roles of three major forms of ncRNAs [microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs)] in orchestrating the four sequential phases of cardiac organogenesis.


Assuntos
Coração/crescimento & desenvolvimento , Miocárdio , RNA não Traduzido , Proliferação de Células , Humanos , MicroRNAs , Miocárdio/citologia , Miocárdio/metabolismo , RNA Longo não Codificante
16.
Gen Physiol Biophys ; 39(2): 187-194, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32329446

RESUMO

We aimed to investigate the effects of CX-C chemokine receptor type 4 (CXCR4) on transforming growth factor (TGF)-ß1-induced cardiac fibrosis in Human cardiac fibroblasts (HCFs). HCFs were stimulated with TGF-ß1, and the level of α-smooth muscle actin (α-SMA) was assessed by immunofluorescence assay. The expression of CXCR4 was detected by Western blotting. Then the cells were incubated with CXCR4 antagonist AMD 3465. Cell viability was measured by CCK-8 assay. The expression of α-SMA, proliferating cell nuclear antigen (PCNA) and Ki67 were examined. Collagen synthesis was detected by sirius red staining. Moreover, the expression of phpspho-Smad2 (p-Smad2) and p-Smad3 were determined. We found that the level of α-SMA was increased after induction with TGF-ß1. The expression of CXCR4 was upregulated in TGF-ß1-treated HCFs. Following treatment with AMD 3465, cell proliferation was inhibited coupled with a decrease in PCNA and Ki67 expression. Additionally, the expression of α-SMA was decreased after being intervened with AMD 3465. Concurrently, the levels of collagen were reduced accompanied by downregulation of Collagen I and III. Furthermore, AMD 3465 treatment decreased the expression of p-Smad2 and p-Smad3. Our findings suggested that CXCR4 antagonist AMD 3465 could alleviate cardiac fibrosis via blocking TGF-ß1-induced activation of Smad2/3 in HCFs.


Assuntos
Colágeno/biossíntese , Fibroblastos/citologia , Miocárdio/citologia , Piridinas/farmacologia , Receptores CXCR4/antagonistas & inibidores , Fator de Crescimento Transformador beta1/farmacologia , Proliferação de Células , Humanos , Transdução de Sinais
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(1): 37-46, 2020 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-32131938

RESUMO

Objective To study the gene expression of cardiac mesenchymal cells in patients with type 2 diabetes mellitus (T2DM)based on a whole-genome high-throughput sequencing dataset,screen differentially expressed genes,analyze the genetics signature of cardiac mesenchymal cells in T2DM patients by bioinformatics analysis,and explore the environmental chemicals related to the key differentially expressed genes. Methods The dataset GSE106177 was obtained from Gene Expression Omnibus (GEO) database.The dataset was pre-processed and analyzed by Network Analyst,Cytoscape 3.7.1,String11.0,CTD,and HMDD for screening for differentially expressed genes,enrichment analysis,establishment of protein-protein interaction (PPI) networks,and screening for relevant environmental chemicals. Results The gene expression pattern of cardiac mesenchymal cells in T2DM patients was significantly different from that in the control group.There were 135 differentially expressed genes,of which 58 (42.96%) were up-regulated and 77 (57.04%) were down-regulated.The differentially expressed genes mainly participated in biological processes such as multicellular organism development,anatomical structure development,and system development and were mainly involved in hepatocellular carcinoma,Cushing's syndrome,and cholesterol metabolism.PPI network showed that UBC was the core protein node.The microRNA-Gene interaction network showed that seven microRNAs,represented by hsa-mir-8485,interacted with the differentially expressed genes.Key T2DM related genes such as UBC,DNER,and CNTN1 interacted with bisphenol A. Conclusions The gene expression profile of cardiac mesenchymal cells markedly changes in T2DM patients,during which UBC may play an important biological role.Bisphenol A exposure may also affect the development and normal function of cardiac cells in T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Miocárdio/citologia , Transcriptoma , Biologia Computacional , Perfilação da Expressão Gênica , Humanos
18.
Life Sci ; 250: 117569, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32201277

RESUMO

Individuals suffering from diabetes have an increased risk of developing cardiovascular complications such as heart failure. Heart failure can be a result of the stiffening of the left ventricle, which occurs when cardiac fibroblasts become "active" and begin to remodel the extracellular matrix (ECM). Fibroblast "activation" can be triggered by the AGE/RAGE signaling cascade. Advanced Glycation End products (AGEs) are produced and accumulate in the ECM over time in a healthy individual, but under hyperglycemic conditions, this process is accelerated. In this study, we investigated how the presence of AGEs in either non-diabetic or diabetic ECM affected fibroblast-mediated matrix remodeling. In order to address this question, diabetic and non-diabetic fibroblasts were embedded in 3D matrices composed of collagen isolated from either non-diabetic or diabetic mice. Fibroblast function was assessed using gel contraction, migration, and protein expression. Non-diabetic fibroblasts displayed similar gel contraction to diabetic cells when embedded in diabetic collagen. Thus, suggesting the diabetic ECM can alter fibroblast function from an "inactive" to "active" state. Addition of AGEs increase the AGE/RAGE cascade leading to increased gel contraction, whereas inhibiting the cascade resulted in little or no gel contraction. These results indicated 1) the ECM from diabetic and non-diabetic mice differ from one another, 2) diabetic ECM can impact fibroblast function and shift them toward an "active" state, and 3) that fibroblasts can modify the ECM through activation of the AGE/RAGE signaling cascade. These results suggested the importance of understanding the impact diabetes has on the ECM and fibroblast function.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais , Animais , Técnicas de Cultura de Células , Colágeno/metabolismo , Cruzamentos Genéticos , Ventrículos do Coração/metabolismo , Masculino , Camundongos , Miocárdio/citologia
19.
Nat Cell Biol ; 22(3): 332-340, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32123336

RESUMO

Mapping of the holistic cell behaviours sculpting the four-chambered mammalian heart has been a goal or previous studies, but so far only success in transparent invertebrates and lower vertebrates with two-chambered hearts has been achieved. Using a live-imaging system comprising a customized vertical light-sheet microscope equipped with a mouse embryo culture module, a heartbeat-gated imaging strategy and a digital image processing framework, we realized volumetric imaging of developing mouse hearts at single-cell resolution and with uninterrupted cell lineages for up to 1.5 d. Four-dimensional landscapes of Nppa+ cardiomyocyte cell behaviours revealed a blueprint for ventricle chamber formation by which biased outward migration of the outermost cardiomyocytes is coupled with cell intercalation and horizontal division. The inner-muscle architecture of trabeculae was developed through dual mechanisms: early fate segregation and transmural cell arrangement involving both oriented cell division and directional migration. Thus, live-imaging reconstruction of uninterrupted cell lineages affords a transformative means for deciphering mammalian organogenesis.


Assuntos
Ventrículos do Coração/citologia , Ventrículos do Coração/embriologia , Processamento de Imagem Assistida por Computador/métodos , Miócitos Cardíacos/citologia , Animais , Divisão Celular , Linhagem da Célula , Movimento Celular , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Coração/embriologia , Camundongos , Microscopia , Morfogênese , Miocárdio/citologia , Análise de Célula Única , Técnicas de Cultura de Tecidos
20.
Food Funct ; 11(2): 1764-1778, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32044910

RESUMO

Dietary methionine restriction (MR) has been reported to extend lifespan, reduce obesity and decrease oxidative damage to mtDNA in the heart of rats, and increase endogenous hydrogen sulfide (H2S) production in the liver and blood. H2S has many potential benefits in the pathophysiology of the cardiovascular system. MR also increases the level of homocysteine (Hcy) in the liver and plasma, but elevated plasma Hcy is a risk factor for cardiovascular disease. Therefore, this study aimed to determine the effect of MR on cardiac function and metabolic status in obese middle-aged mice and its possible mechanisms. C57BL/6J mice (aged approximately 28 weeks) were divided into six dietary groups: CON (0.86% methionine + 4% fat), CMR40 (0.52% methionine + 4% fat), CMR80 (0.17% methionine + 4% fat), HFD (0.86% methionine + 24% fat), HMR40 (0.52% methionine + 24% fat) and HMR80 (0.17% methionine + 24% fat) for 15 consecutive weeks. Our results showed that 80% MR improves systolic dysfunction in middle-aged obese mice and enhances myocardial energy metabolism. 80% MR also reduces myocardial oxidative stress and improves inflammatory response. In addition, 80% MR increased mice Hcy levels and activated remethylation and transsulfur pathways of Hcy and promoted endogenous H2S production in the heart. 40% MR has the same trend, but is not significant. Moreover 40% MR at variance with 80% MR, did not decrease the body weight in both control and high-fat diet mice. These findings suggest that MR can improve myocardial energy metabolism, reduce heart inflammation and oxidative stress by increasing cardiac H2S production, and improve cardiac dysfunction in middle-aged obese mice.


Assuntos
Dieta , Metionina , Miocárdio , Obesidade/metabolismo , Animais , Peso Corporal , Cardiomegalia/metabolismo , Metabolismo Energético/fisiologia , Homocisteína/metabolismo , Sulfeto de Hidrogênio/metabolismo , Masculino , Metionina/administração & dosagem , Metionina/metabolismo , Metionina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Miocárdio/citologia , Miocárdio/metabolismo , Estresse Oxidativo/fisiologia
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