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2.
PLoS One ; 15(7): e0236413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735567

RESUMO

OBJECTIVE: Although a number of modifiable and non-modifiable causes were implicated in arterial stiffness, its pathogenesis remains elusive, and very little is known about aortic elasticity in supraventricular arrhythmias. The potential role of disturbed kynurenine metabolism in the pathogenesis of cardiovascular disease has been recently suggested. Thus, we studied the correlations of aortic stiffness and echocardiographic parameters with biochemical markers and serum level of kynurenic acid (KYNA), an endothelial derivative of tryptophan, formed along the kynurenine pathway, among patients with atrial fibrillation (AF). METHODS: Study cohort comprised 100 patients with persistent AF (43 females/57 males). Arterial stiffness index (ASI), structural and functional indices of left atrium (LA) and left ventricle (LV) were evaluated electrocardiographically. Biochemical analyses included the measurements of serum KYNA (HPLC) and of the selected markers of lipids and glucose metabolism, thyroid status, kidney function, inflammation and coagulation. RESULTS: KYNA (ß = 0.389, P = 0.029), homocysteine (ß = 0.256, P = 0.40), total cholesterol (ß = 0.814; P = 0.044), LDL (ß = 0.663; P = 0.44), TSH (ß = 0.262, P = 0.02), fT3 (ß = -0.333, P = 0.009), fT4 (ß = -0.275, P = 0.043) and creatinine (ß = 0.374, P = 0.043) were independently correlated with ASI. ASI was also independently associated with LV end-systolic diameter (LVEDd; ß = 1.751, P = 0.045), midwall fractional shortening (mFS; ß = -1.266, P = 0.007), ratio mFS/end-systolic stress (mFS/ESS; ß = -0.235, P = 0.026), LV shortening fraction (FS; ß = -0.254, P = 0.017), and LA volume index (LAVI; ß = 0.944, P = 0.022). CONCLUSIONS: In patients with AF, aortic stiffness correlated positively with KYNA, biochemical risk factors of atherosclerosis and with the indices of diastolic dysfunction of LV and LA. Revealed relationship between ASI and KYNA is an original observation, suggesting a potential role of disturbed kynurenine metabolism in the pathogenesis of arterial stiffening. KYNA, synthesis of which is influenced by homocysteine, emerges as a novel, non-classical factor associated with ASI in patients with AF.


Assuntos
Aterosclerose/sangue , Fibrilação Atrial/sangue , Biomarcadores/sangue , Ácido Cinurênico/sangue , Adulto , Aorta/diagnóstico por imagem , Aorta/patologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Fibrilação Atrial/fisiopatologia , Estudos Transversais , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Cinurenina/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Rigidez Vascular/fisiologia
3.
Circ Arrhythm Electrophysiol ; 13(8): e008627, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32654514

RESUMO

BACKGROUND: During acute infections, the risk of malignant ventricular arrhythmias is increased, partly because of a higher propensity to develop QTc prolongation. Although it is generally believed that QTc changes almost exclusively result from concomitant treatment with QT-prolonging antimicrobials, direct effects of inflammatory cytokines on ventricular repolarization are increasingly recognized. We hypothesized that systemic inflammation per se can significantly prolong QTc during acute infections, via cytokine-mediated changes in K+ channel expression. METHODS: We evaluated (1) the frequency of QTc prolongation and its association with inflammatory markers, in patients with different types of acute infections, during active disease and remission; (2) the prevalence of acute infections in a cohort of consecutive patients with Torsades de Pointes; (3) the relationship between K+ channel mRNA levels in ventricles and peripheral blood mononuclear cells and their changes in patients with acute infection over time. RESULTS: In patients with acute infections, regardless of concomitant QT-prolonging antimicrobial treatments, QTc was significantly prolonged but rapidly normalized in parallel to CRP (C-reactive protein) and cytokine level reduction. Consistently in the Torsades de Pointes cohort, concomitant acute infections were highly prevalent (30%), despite only a minority (25%) of these cases were treated with QT-prolonging antimicrobials. KCNJ2 K+ channel expression in peripheral blood mononuclear cell, which strongly correlated to that in ventricles, inversely associated to CRP and IL (interleukin)-1 changes in acute infection patients. CONCLUSIONS: During acute infections, systemic inflammation rapidly induces cytokine-mediated ventricular electrical remodeling and significant QTc prolongation, regardless concomitant antimicrobial therapy. Although transient, these changes may significantly increase the risk of life-threatening ventricular arrhythmia in these patients. It is timely and warranted to transpose these findings to the current coronavirus disease 2019 (COVID-19) pandemic, in which both increased amounts of circulating cytokines and cardiac arrhythmias are demonstrated along with a frequent concomitant treatment with several QT-prolonging drugs. Graphic Abstract: A graphic abstract is available for this article.


Assuntos
Doenças Transmissíveis/metabolismo , Citocinas/metabolismo , Parada Cardíaca/metabolismo , Frequência Cardíaca , Ventrículos do Coração/metabolismo , Inflamação/metabolismo , Leucócitos Mononucleares/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Torsades de Pointes/metabolismo , Potenciais de Ação , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Infecciosos/efeitos adversos , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/fisiopatologia , Feminino , Parada Cardíaca/epidemiologia , Parada Cardíaca/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Humanos , Inflamação/epidemiologia , Inflamação/fisiopatologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Canais de Potássio Corretores do Fluxo de Internalização/genética , Prevalência , Fatores de Risco , Transdução de Sinais , Fatores de Tempo , Torsades de Pointes/epidemiologia , Torsades de Pointes/fisiopatologia , Adulto Jovem
4.
PLoS One ; 15(7): e0236632, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716972

RESUMO

BACKGROUND: To assess left ventricular hypertrophy, actual left ventricular mass (LVM) normalized for body size has to be compared to the LVM normative data. However, only some published normative echocardiographic data have been produced separately for girls and boys; numerous normative data for the pediatric population are not sex-specific. Thus, this study aimed to assess whether the LVM normative data should be developed separately for girls and boys practicing sports. METHODS: Left ventricular mass was computed for 331 girls and 490 boys, 5-19 years old, based on echocardiography. The effect of sex on the relationship between LVM and body size was evaluated using a linear regression model. Seven sets of the LVM normative data were developed, using different methodologies, to test concordance between sex-specific and non-specific normative data. Every set consisted of normative data that was sex-specific and non-specific. Upon these normative data, for every study participant, seven pairs of LVM z-scores were calculated based on her/his actual LVM. Each pair consisted of z-scores computed based on sex-specific and non-specific normative data from the same set. RESULTS: The regression lines fitted to the data points corresponding to LVM of boys had a higher slope than of girls, indicating that sex affects the relationship between LVM and body size. The mean differences between the paired LVM z-scores differed significantly from 0. The percentage of discordant indications, depending on the normalization method, ranged from 66.7% to 100% in girls and from 35.4% to 50% in boys. Application of the LVM normative data that were not sex-specific made relative LVM underestimated in girls and overestimated in boys. CONCLUSION: The LVM normative data should be developed separately for girls and boys practicing sports. Application of normative data that are not sex-specific results in an underestimation of relative LVM in girls and overestimation in boys.


Assuntos
Ventrículos do Coração , Caracteres Sexuais , Adolescente , Atletas , Tamanho Corporal , Criança , Pré-Escolar , Ecocardiografia , Feminino , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/fisiopatologia , Modelos Lineares , Masculino , Estudos Retrospectivos , Adulto Jovem
5.
Nat Commun ; 11(1): 2843, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487995

RESUMO

Poor access to human left ventricular myocardium is a significant limitation in the study of heart failure (HF). Here, we utilise a carefully procured large human heart biobank of cryopreserved left ventricular myocardium to obtain direct molecular insights into ischaemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM), the most common causes of HF worldwide. We perform unbiased, deep proteomic and metabolomic analyses of 51 left ventricular (LV) samples from 44 cryopreserved human ICM and DCM hearts, compared to age-, gender-, and BMI-matched, histopathologically normal, donor controls. We report a dramatic reduction in serum amyloid A1 protein in ICM hearts, perturbed thyroid hormone signalling pathways and significant reductions in oxidoreductase co-factor riboflavin-5-monophosphate and glycolytic intermediate fructose-6-phosphate in both; unveil gender-specific changes in HF, including nitric oxide-related arginine metabolism, mitochondrial substrates, and X chromosome-linked protein and metabolite changes; and provide an interactive online application as a publicly-available resource.


Assuntos
Cardiomiopatia Dilatada/metabolismo , Isquemia Miocárdica/metabolismo , Caracteres Sexuais , Transdução de Sinais , Cardiomiopatia Dilatada/patologia , Feminino , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Masculino , Metaboloma , Metabolômica , Pessoa de Meia-Idade , Isquemia Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Análise de Componente Principal , Mapas de Interação de Proteínas , Proteoma/metabolismo , Proteômica , Doadores de Tecidos
6.
PLoS One ; 15(6): e0234087, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511282

RESUMO

BACKGROUND: Ventricular septal perforation and left ventricular aneurysm are examples of potentially fatal complications of myocardial infarction. While various artificial materials are used in the repair of these issues, the possibility of associated infection and calcification is non-negligible. Cell-seeded biodegradable tissue-engineered patches may be a potential solution. This study evaluated the feasibility of a new left ventricular patch rat model to study neotissue formation in biodegradable cardiac patches. METHODS: Human induced pluripotent stem cell-derived cardiac progenitor cells (hiPS-CPCs) were cultured onto biodegradable patches composed of polyglycolic acid and a 50:50 poly (l-lactide-co-ε-caprolactone) copolymer for one week. After culturing, patches were implanted into left ventricular walls of male athymic rats. Unseeded controls were also used (n = 10/group). Heart conditions were followed by echocardiography and patches were subsequently explanted at 1, 2, 6, and 9 months post-implantation for histological evaluation. RESULT: Throughout the study, no patches ruptured demonstrating the ability to withstand the high pressure left ventricular system. One month after transplantation, the seeded patch did not stain positive for human nuclei. However, many new blood vessels formed within patches with significantly greater vessels in the seeded group at the 6 month time point. Echocardiography showed no significant difference in left ventricular contraction rate between the two groups. Calcification was found inside patches after 6 months, but there was no significant difference between groups. CONCLUSION: We have developed a surgical method to implant a bioabsorbable scaffold into the left ventricular environment of rats with a high survival rate. Seeded hiPS-CPCs did not differentiate into cardiomyocytes, but the greater number of new blood vessels in seeded patches suggests the presence of cell seeding early in the remodeling process might provide a prolonged effect on neotissue formation. This experiment will contribute to the development of a treatment model for left ventricular failure using iPS cells in the future.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Engenharia Tecidual , Implantes Absorvíveis , Animais , Modelos Animais de Doenças , Ecocardiografia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/transplante , Poliésteres/química , Ácido Poliglicólico/química , Ratos , Ratos Nus , Tecidos Suporte/química , Troponina T/metabolismo , Função Ventricular
7.
PLoS Comput Biol ; 16(6): e1007572, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32502205

RESUMO

Ventricular contraction is roughly proportional to the amount of calcium released from the Sarcoplasmic Reticulum (SR) during systole. While it is rather straightforward to measure calcium levels and contractibility under different physiological conditions, the complexity of calcium handling during systole and diastole has made the prediction of its release at steady state impossible. Here we approach the problem analyzing the evolution of intracellular and extracellular calcium fluxes during a single beat which is away from homeostatic balance. Using an in-silico subcellular model of rabbit ventricular myocyte, we show that the high dimensional nonlinear problem of finding the steady state can be reduced to a two-variable general equilibrium condition where pre-systolic calcium level in the cytosol and in the SR must fulfill simultaneously two different equalities. This renders calcium homeostasis as a problem that can be studied in terms of its equilibrium structure, leading to precise predictions of steady state from single-beat measurements. We show how changes in ion channels modify the general equilibrium, as shocks would do in general equilibrium macroeconomic models. This allows us to predict when an enhanced entrance of calcium in the cell reduces its contractibility and explain why SERCA gene therapy, a change in calcium handling to treat heart failure, might fail to improve contraction even when it successfully increases SERCA expression.


Assuntos
Cálcio/metabolismo , Ventrículos do Coração/metabolismo , Íons , Células Musculares/metabolismo , Animais , Simulação por Computador , Citosol/metabolismo , Homeostase , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Coelhos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Sístole
8.
PLoS One ; 15(6): e0235220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584885

RESUMO

BACKGROUND: Approximately 30,000 patients with blunt cardiac trauma are recorded each year in the United States. Blunt cardiac injuries after trauma are associated with a longer hospital stay and a poor overall outcome. Organ damage after trauma is linked to increased systemic release of pro-inflammatory cytokines and damage-associated molecular patterns. However, the interplay between polytrauma and local cardiac injury is unclear. Additionally, the impact of surgical intervention on this process is currently unknown. This study aimed to determine local cardiac immunological and structural alterations after multiple trauma. Furthermore, the impact of the chosen fracture stabilization strategy (reamed versus non-reamed femoral nailing) on cardiac alterations was studied. EXPERIMENTAL APPROACH: 15 male pigs were either exposed to multiple trauma (blunt chest trauma, laparotomy, liver laceration, femur fracture and haemorrhagic shock) or sham conditions. Blood samples as well as cardiac tissue were analysed 4 h and 6 h after trauma. Additionally, murine HL-1 cells were exposed to a defined polytrauma-cocktail, mimicking the pro-inflammatory conditions after multiple trauma in vitro. RESULTS: After multiple trauma, cardiac structural changes were observed in the left ventricle. More specifically, alterations in the alpha-actinin and desmin protein expression were found. Cardiac structural alterations were accompanied by enhanced local nitrosative stress, increased local inflammation and elevated systemic levels of the high-mobility group box 1 protein. Furthermore, cardiac alterations were observed predominantly in pigs that were treated by non-reamed intramedullary reaming. The polytrauma-cocktail impaired the viability of HL-1 cells in vitro, which was accompanied by a release of troponin I and HFABP. DISCUSSION: Multiple trauma induced cardiac structural alterations in vivo, which might contribute to the development of early myocardial damage (EMD). This study also revealed that reamed femoral nailing (reamed) is associated with more prominent immunological cardiac alterations compared to nailing without reaming (non-reamed). This suggests that the choice of the initial fracture treatment strategy might be crucial for the overall outcome as well as for any post-traumatic cardiac consequences.


Assuntos
Pinos Ortopédicos/efeitos adversos , Fraturas do Fêmur/cirurgia , Traumatismo Múltiplo/patologia , Miocárdio/patologia , Actinina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular , Conexina 43/metabolismo , Citocinas/análise , Citocinas/metabolismo , Desmina/metabolismo , Fraturas do Fêmur/patologia , Proteína HMGB1/análise , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Inflamação , Masculino , Camundongos , Traumatismo Múltiplo/metabolismo , Traumatismo Múltiplo/veterinária , Miocárdio/metabolismo , Estresse Nitrosativo , Suínos , Troponina I/análise
9.
PLoS Genet ; 16(5): e1008782, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32421721

RESUMO

The planar cell polarity pathway is required for heart development and whilst the functions of most pathway members are known, the roles of the jnk genes in cardiac morphogenesis remain unknown as mouse mutants exhibit functional redundancy, with early embryonic lethality of compound mutants. In this study zebrafish were used to overcome early embryonic lethality in mouse models and establish the requirement for Jnk in heart development. Whole mount in-situ hybridisation and RT-PCR demonstrated that evolutionarily conserved alternative spliced jnk1a and jnk1b transcripts were expressed in the early developing heart. Maternal zygotic null mutant zebrafish lines for jnk1a and jnk1b, generated using CRISPR-Cas9, revealed a requirement for jnk1a in formation of the proximal, first heart field (FHF)-derived portion of the cardiac ventricular chamber. Rescue of the jnk1a mutant cardiac phenotype was only possible by injection of the jnk1a EX7 Lg alternatively spliced transcript. Analysis of mutants indicated that there was a reduction in the size of the hand2 expression field in jnk1a mutants which led to a specific reduction in FHF ventricular cardiomyocytes within the anterior lateral plate mesoderm. Moreover, the jnk1a mutant ventricular defect could be rescued by injection of hand2 mRNA. This study reveals a novel and critical requirement for Jnk1 in heart development and highlights the importance of alternative splicing in vertebrate cardiac morphogenesis. Genetic pathways functioning through jnk1 may be important in human heart malformations with left ventricular hypoplasia.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ventrículos do Coração/citologia , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Processamento Alternativo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Contagem de Células , Células Cultivadas , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Ventrículos do Coração/embriologia , Ventrículos do Coração/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
10.
PLoS One ; 15(5): e0231695, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392258

RESUMO

We present a novel modification of genetic algorithm (GA) which determines personalized parameters of cardiomyocyte electrophysiology model based on set of experimental human action potential (AP) recorded at different heart rates. In order to find the steady state solution, the optimized algorithm performs simultaneous search in the parametric and slow variables spaces. We demonstrate that several GA modifications are required for effective convergence. Firstly, we used Cauchy mutation along a random direction in the parametric space. Secondly, relatively large number of elite organisms (6-10% of the population passed on to new generation) was required for effective convergence. Test runs with synthetic AP as input data indicate that algorithm error is low for high amplitude ionic currents (1.6±1.6% for IKr, 3.2±3.5% for IK1, 3.9±3.5% for INa, 8.2±6.3% for ICaL). Experimental signal-to-noise ratio above 28 dB was required for high quality GA performance. GA was validated against optical mapping recordings of human ventricular AP and mRNA expression profile of donor hearts. In particular, GA output parameters were rescaled proportionally to mRNA levels ratio between patients. We have demonstrated that mRNA-based models predict the AP waveform dependence on heart rate with high precision. The latter also provides a novel technique of model personalization that makes it possible to map gene expression profile to cardiac function.


Assuntos
Potenciais de Ação , Coração/fisiologia , Miócitos Cardíacos/fisiologia , Potenciais de Ação/genética , Potenciais de Ação/fisiologia , Expressão Gênica , Transplante de Coração , Ventrículos do Coração/metabolismo , Humanos , Modelos Biológicos , Técnicas de Patch-Clamp , RNA-Seq , Doadores de Tecidos
11.
Am J Physiol Heart Circ Physiol ; 319(1): H183-H191, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32469637

RESUMO

In pulmonary hypertension (PH) a proinflammatory milieu drives pulmonary vascular remodeling, maladaptive right ventricular (RV) remodeling, and right-sided heart failure. There is an unmet need for RV-targeted pharmaco-therapies to improve mortality. Targeting of the P2X7 receptor (P2X7R) reduces pulmonary pressures; however, its effects on the RV are presently unknown. We investigated the effect of P2X7 receptor (P2X7R) inhibition on the pulmonary vasculature and RV remodeling using the novel P2X7R antagonist PKT100. C57BL/6 mice were administered intratracheal bleomycin or saline and treated with PKT100 (0.2 mg·kg-1·day-1) or DMSO vehicle. RV was assessed by right heart catheterization and echocardiography, 21 days posttreatment. Cytokines in serum and bronchoalveolar lavage fluid (BALF) were analyzed by ELISA and flow cytometry. Lungs and hearts were analyzed histologically for pulmonary vascular and RV remodeling. Focused-PCR using genes involved in RV remodeling was performed. Right ventricular systolic pressure (RVSP) was elevated in bleomycin-treated mice (30.2 ± 1.1; n = 7) compared with control mice (23.5 ± 1.0; n = 10; P = 0.008). PKT100 treatment did not alter RVSP (32.4 ± 1.8; n = 9), but it substantially improved survival (93% vs. 57% DMSO). There were no differences between DMSO and PKT100 bleomycin mice in pulmonary inflammation or remodeling. However, RV hypertrophy was reduced in PKT100 mice. Bleomycin decreased echocardiographic surrogates of RV systolic performance, which were significantly improved with PKT100. Four genes involved in RV remodeling (RPSA, Rplp0, Add2, and Scn7a) were differentially expressed between DMSO and PKT100-treated groups. The novel P2X7R inhibitor, PKT100, attenuates RV hypertrophy and improves RV contractile function and survival in a mouse model of PH independently of effects on the pulmonary vasculature. PKT100 may improve ventricular response to increased afterload and merits further investigation into the potential role of P2X7R antagonists as direct RV-focused therapies in PH.NEW & NOTEWORTHY This study demonstrates the therapeutic potential for right-sided heart failure of a novel inhibitor of the P2X7 receptor (P2X7R). Inflammatory signaling and right ventricular function were improved in a mouse model of pulmonary fibrosis with secondary pulmonary hypertension when treated with this inhibitor. Importantly, survival was also improved, suggesting that this inhibitor, and other P2X7R antagonists, could be uniquely effective in right ventricle (RV)-targeted therapy in pulmonary hypertension. This addresses a major limitation of current treatment options, where the significant improvements in pulmonary pressures ultimately do not prevent mortality due to RV failure.


Assuntos
Ventrículos do Coração/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Animais , Pressão Sanguínea , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/sangue , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores de Laminina/genética , Receptores de Laminina/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Remodelação Ventricular , Canais de Sódio Disparados por Voltagem/genética , Canais de Sódio Disparados por Voltagem/metabolismo
12.
Medicine (Baltimore) ; 99(19): e19992, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32384453

RESUMO

The high-sensitivity cardiac troponin I (hs-cTnI) in serum can increase due to an increase in left ventricular (LV) overload in individuals with hypertension. Since LV voltage on an electrocardiogram (ECG) reflects LV load, it is possible that LV voltage is closely associated with hs-cTnI in individuals without hypertension. This study investigated the association between LV voltage indices and serum hs-cTnI levels in normotensive Japanese individuals.Subjects who visited the Enshu Hospital for a health check-up were screened for their eligibility. Subjects with renal dysfunction, cancer, active inflammatory disease, or a history of cardiovascular events were excluded, as were subjects with obvious ST segment or T wave abnormality, Wolff-Parkinson-White syndrome, pacemaker implantation, or frequent arrhythmia in the ECG. Exclusion of individuals with hypertension left 803 subjects (54.8 ±â€Š11.3 years) for final inclusion. The R wave voltage in lead V5 (RV5 voltage), the Sokolow-Lyon voltage (a sum of the QRS wave (a complex wave consists of Q, R, and S wave) of the S wave voltage in lead V1 and the R wave voltage in lead V5), and the Cornell product (a product of QRS duration and QRS voltage) were evaluated by ECG as LV voltage indices. Laboratory measurements included serum hs-cTnI levels. Possible associations between indices of LV voltage on ECG and serum hs-cTnI levels were cross-sectionally investigated in the normotensive subjects.The median values [interquartile range] of hs-cTnI and BNP were and 2.1 [1.4-3.0] and 13.8 [7.7-24.9] pg/mL, respectively. Multivariate regression analysis identified that the levels of hs-cTnI, but not BNP, were significantly associated with RV5 voltage (ß 0.090, P = .0087), Sokolow-Lyon voltage (ß 0.112, P = .0009), and Cornell product (ß 0.101, P = .039) after adjustment for possible confounding factors. Moreover, the RV5 voltage, Sokolow-Lyon voltage, and Cornell product were significantly associated with the hs-cTnI levels after adjustment for possible confounding factors including ECG findings (ß 0.109, P = .0075; ß 0.125, P = .0010; and ß 0.096, P = .0116, respectively).Indices of LV voltage in ECG had close associations with serum hs-cTnI levels in normotensive subjects. These findings support that the ECG findings of LV voltage have significant associations with slight myocardial micro-damage even in normotensive subjects.


Assuntos
Eletrocardiografia/métodos , Ventrículos do Coração , Miocárdio/metabolismo , Troponina I/sangue , Pressão Sanguínea/fisiologia , Correlação de Dados , Feminino , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Japão , Masculino , Pessoa de Meia-Idade
13.
J Vis Exp ; (158)2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32364545

RESUMO

It has been shown that endocardial endothelial cells (EECs) and coronary endothelial cells (CECs) differ in origin, development, markers, and functions. Consequently, these two cell populations play unique roles in cardiac diseases. Current studies involving isolated endothelial cells investigate cell populations consisting of both EECs and CECs. This protocol outlines a method to independently isolate these two cell populations for cell-specific characterization. Following the collection of the left and right ventricular free wall, endothelial cells from the outer surface and inner surface are separately liberated using a digestion buffer solution. The sequential digestion of the outer surface and the inner endocardial layer retained separation of the two endothelial cell populations. The separate isolation of EECs and CECs is further verified through the identification of markers specific to each population. Based on previously published single cell RNA profiling in the mouse heart, the Npr3, Hapln1, and Cdh11 gene expression is unique to EECs; while Fabp4, Mgll, and Cd36 gene expression is unique to CECs. qPCR data revealed enriched expression of these characteristic markers in their respective samples, indicating successful EEC and CEC isolation, as well as maintenance of cell phenotype, enabling further cell-specific functional analysis.


Assuntos
Vasos Coronários/citologia , Endocárdio/citologia , Endotélio Vascular/citologia , Ventrículos do Coração/citologia , Coração/fisiologia , Animais , Biomarcadores/metabolismo , Células Cultivadas , Vasos Coronários/metabolismo , Endocárdio/metabolismo , Endotélio Vascular/metabolismo , Perfilação da Expressão Gênica , Ventrículos do Coração/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Circ Heart Fail ; 13(4): e006409, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32264717

RESUMO

BACKGROUND: Ischemic tolerance of donor hearts has a major impact on the efficiency in utilization and clinical outcomes. Molecular events during storage may influence the severity of ischemic injury. METHODS: RNA sequencing was used to study the transcriptional profile of the human left ventricle (LV, n=4) and right ventricle (RV, n=4) after 0, 4, and 8 hours of cold storage in histidine-tryptophan-ketoglutarate preservation solution. Gene set enrichment analysis and gene ontology analysis was used to examine transcriptomic changes with cold storage. Terminal deoxynucleotidyl transferase 2´-Deoxyuridine, 5´-Triphosphate nick end labeling and p65 staining was used to examine for cell death and NFκB activation, respectively. RESULTS: The LV showed activation of genes related to inflammation and allograft rejection but downregulation of oxidative phosphorylation and fatty acid metabolism pathway genes. In contrast, inflammation-related genes were down-regulated in the RV and while oxidative phosphorylation genes were activated. These transcriptomic changes were most significant at the 8 hours with much lower differences observed between 0 and 4 hours. RNA velocity estimates corroborated the finding that immune-related genes were activated in the LV but not in the RV during storage. With increasing preservation duration, the LV showed an increase in nuclear translocation of NFκB (p65), whereas the RV showed increased cell death close to the endocardium especially at 8 hours. CONCLUSIONS: Our results demonstrated that the LV and RV of human donor hearts have distinct responses to cold ischemic storage. Transcriptomic changes related to inflammation, oxidative phosphorylation, and fatty acid metabolism pathways as well as cell death and NFκB activation were most pronounced after 8 hours of storage.


Assuntos
Temperatura Baixa/efeitos adversos , Transplante de Coração , Ventrículos do Coração/metabolismo , Preservação de Órgãos , Disfunção Primária do Enxerto/genética , Transcriptoma , Apoptose/efeitos dos fármacos , Apoptose/genética , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Perfilação da Expressão Gênica , Glucose/farmacologia , Transplante de Coração/efeitos adversos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Humanos , Inflamação/genética , Inflamação/patologia , Manitol/farmacologia , Preservação de Órgãos/efeitos adversos , Soluções para Preservação de Órgãos/farmacologia , Cloreto de Potássio/farmacologia , Disfunção Primária do Enxerto/patologia , Disfunção Primária do Enxerto/prevenção & controle , Procaína/farmacologia , Fatores de Risco , Fatores de Tempo , Transcriptoma/efeitos dos fármacos
15.
Proc Natl Acad Sci U S A ; 117(13): 7461-7470, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32170008

RESUMO

Local control of blood flow in the heart is important yet poorly understood. Here we show that ATP-sensitive K+ channels (KATP), hugely abundant in cardiac ventricular myocytes, sense the local myocyte metabolic state and communicate a negative feedback signal-correction upstream electrically. This electro-metabolic voltage signal is transmitted instantaneously to cellular elements in the neighboring microvascular network through gap junctions, where it regulates contractile pericytes and smooth muscle cells and thus blood flow. As myocyte ATP is consumed in excess of production, [ATP]i decreases to increase the openings of KATP channels, which biases the electrically active myocytes in the hyperpolarization (negative) direction. This change leads to relative hyperpolarization of the electrically connected cells that include capillary endothelial cells, pericytes, and vascular smooth muscle cells. Such hyperpolarization decreases pericyte and vascular smooth muscle [Ca2+]i levels, thereby relaxing the contractile cells to increase local blood flow and delivery of nutrients to the local cardiac myocytes and to augment ATP production by their mitochondria. Our findings demonstrate the pivotal roles of local cardiac myocyte metabolism and KATP channels and the minor role of inward rectifier K+ (Kir2.1) channels in regulating blood flow in the heart. These findings establish a conceptually new framework for understanding the hugely reliable and incredibly robust local electro-metabolic microvascular regulation of blood flow in heart.


Assuntos
Circulação Coronária/fisiologia , Coração/fisiologia , Canais KATP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Células Endoteliais/metabolismo , Feminino , Ventrículos do Coração/metabolismo , Canais KATP/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Músculo Liso Vascular/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos de Músculo Liso/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/fisiologia , Transdução de Sinais
16.
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
17.
J Cardiovasc Magn Reson ; 22(1): 13, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036784

RESUMO

BACKGROUND: Using cardiovascular magnetic resonance imaging (CMR), it is possible to detect diffuse fibrosis of the left ventricle (LV) in patients with atrial fibrillation (AF), which may be independently associated with recurrence of AF after ablation. By conducting CMR, clinical, electrophysiology and biomarker assessment we planned to investigate LV myocardial fibrosis in patients undergoing AF ablation. METHODS: LV fibrosis was assessed by T1 mapping in 31 patients undergoing percutaneous ablation for AF. Galectin-3, coronary sinus type I collagen C terminal telopeptide (ICTP), and type III procollagen N terminal peptide were measured with ELISA. Comparison was made between groups above and below the median for LV extracellular volume fraction (ECV), followed by regression analysis. RESULTS: On linear regression analysis LV ECV had significant associations with invasive left atrial pressure (Beta 0.49, P = 0.008) and coronary sinus ICTP (Beta 0.75, P < 0.001), which remained significant on multivariable regression. CONCLUSION: LV fibrosis in patients with AF is associated with left atrial pressure and invasively measured levels of ICTP turnover biomarker.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda , Remodelação Ventricular , Adulto , Idoso , Fibrilação Atrial/sangue , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Função do Átrio Esquerdo , Pressão Atrial , Biomarcadores/sangue , Ablação por Cateter , Colágeno Tipo I/sangue , Técnicas Eletrofisiológicas Cardíacas , Feminino , Fibrose , Galectina 3/sangue , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Valor Preditivo dos Testes , Pró-Colágeno/sangue
18.
PLoS One ; 15(2): e0217732, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32012157

RESUMO

BACKGROUND: Ventricle retraining has been extensively studied by our laboratory. Previous studies have demonstrated that intermittent overload causes a more efficient ventricular hypertrophy. The adaptive mechanisms involved in the ventricle retraining are not completely established. This study assessed vascular endothelial growth factor (VEGF) expression in the ventricles of goats submitted to systolic overload. METHODS: Twenty-one young goats were divided into 3 groups (7 animals each): control, 96-hour continuous systolic overload, and intermittent systolic overload (four 12-hour periods of systolic overload paired with 12-hour resting period). During the 96-hour protocol, systolic overload was adjusted to achieve a right ventricular (RV) / aortic pressure ratio of 0.7. Hemodynamic evaluations were performed daily before and after systolic overload. Echocardiograms were obtained preoperatively and at protocol end to measure cardiac masses thickness. At study end, the animals were killed for morphologic evaluation and immunohistochemical assessment of VEGF expression. RESULTS: RV-trained groups developed hypertrophy of RV and septal masses, confirmed by increased weight and thickness, as expected. In the study groups, there was a small but significantly increased water content of the RV and septum compared with those in the control group (p<0.002). VEGF expression in the RV myocardium was greater in the intermittent group (2.89% ± 0.41%) than in the continuous (1.80% ± 0.19%) and control (1.43% ± 0.18%) groups (p<0.023). CONCLUSIONS: Intermittent systolic overload promotes greater upregulation of VEGF expression in the subpulmonary ventricle, an adaptation that provides a mechanism for increased myocardial perfusion during the rapid myocardial hypertrophy of young goats.


Assuntos
Cardiomegalia/metabolismo , Artéria Pulmonar/cirurgia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Pressão Sanguínea , Cardiomegalia/cirurgia , Cabras , Ventrículos do Coração/metabolismo , Ventrículos do Coração/cirurgia , Masculino , Sístole , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/genética
19.
PLoS One ; 15(2): e0218228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32032358

RESUMO

Systemic and central cardiovascular adaptations may vary in response to chronic exercise performed with different intensities and volumes. This study compared the effects of aerobic training with different intensities but equivalent volume upon microvascular reactivity in cremaster muscle and myocardial biomarkers of oxidative stress in Wistar rats. After peak oxygen uptake (VO2peak) assessment, rats (n = 24) were assigned into three groups: moderate-intensity exercise training (MI); high-intensity exercise training (HI); sedentary control (SC). Treadmill training occurred during 4 weeks, with exercise bouts matched by the energy expenditure (3.0-3.5 Kcal). Microvascular reactivity was assessed in vivo by intravital microscopy in cremaster muscle arterioles, while biomarkers of oxidative stress and eNOS expression were quantified at left ventricle and at aorta, respectively. Similar increasing vs. sedentary control group (SC) occurred in moderate intensity training group (MI) and high-intensity training group (HI) for endothelium-dependent vasodilation (10-4M: MI: 168.7%, HI: 164.6% vs. SC: 146.6%, P = 0.0004). Superoxide dismutase (SOD) (HI: 0.13 U/mg vs. MI: 0.09 U/mg and SC: 0.06 U/mg; P = 0.02), glutathione peroxidase (GPX) (HI: 0.00038 U/mg vs. MI: 0.00034 U/mg and SC: 0.00024 U/mg; P = 0.04), and carbonyl protein content (HI: 0.04 U/mg vs. MI: 0.03 U/mg and SC: 0.01 U/mg; P = 0.003) increased only in HI. No difference across groups was detected for catalase (CAT) (P = 0.12), Thiobarbituric acid reactive substances (TBARS) (P = 0.38) or eNOS expression in aorta (P = 0.44). In conclusion, higher exercise intensity induced greater improvements in myocardium antioxidant defenses, while gains in microvascular reactivity appeared to rely more on exercise volume than intensity.


Assuntos
Terapia por Exercício/métodos , Isquemia Miocárdica/terapia , Estresse Oxidativo , Condicionamento Físico Animal/métodos , Vasodilatação , Animais , Aorta/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Ventrículos do Coração/metabolismo , Masculino , Microvasos/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Consumo de Oxigênio , Carbonilação Proteica , Ratos , Ratos Wistar , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
20.
Oxid Med Cell Longev ; 2020: 3690123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064022

RESUMO

Thioridazine (THIO) is a phenothiazine derivative that is mainly used for the treatment of psychotic disorders. However, cardiac arrhythmias especially QT interval prolongation associated with the application of this compound have received serious attention after its introduction into clinical practice, and the mechanisms underlying the cardiotoxicity induced by THIO have not been well defined. The present study was aimed at exploring the long-term effects of THIO on the hERG and L-type calcium channels, both of which are relevant to the development of QT prolongation. The hERG current (I hERG) and the calcium current (I Ca-L) were measured by patch clamp techniques. Protein levels were analyzed by Western blot, and channel-chaperone interactions were determined by coimmunoprecipitation. Reactive oxygen species (ROS) were determined by flow cytometry and laser scanning confocal microscopy. Our results demonstrated that THIO induced hERG channel deficiency but did not alter channel kinetics. THIO promoted ROS production and stimulated endoplasmic reticulum (ER) stress and the related proteins. The ROS scavenger N-acetyl cysteine (NAC) significantly attenuated hERG reduction induced by THIO and abolished the upregulation of ER stress marker proteins. Meanwhile, THIO increased the degradation of hERG channels via disrupting hERG-Hsp70 interactions. The disordered hERG proteins were degraded in proteasomes after ubiquitin modification. On the other hand, THIO increased I Ca-L density and intracellular Ca2+ ([Ca2+]i) in neonatal rat ventricular cardiomyocytes (NRVMs). The specific CaMKII inhibitor KN-93 attenuated the intracellular Ca2+ overload, indicating that ROS-mediated CaMKII activation promoted calcium channel activation induced by THIO. Optical mapping analysis demonstrated the slowing effects of THIO on cardiac repolarization in mouse hearts. THIO significantly prolonged APD50 and APD90 and increased the incidence of early afterdepolarizations (EADs). In human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), THIO also resulted in APD prolongation. In conclusion, dysfunction of hERG channel proteins and activation of L-type calcium channels via ROS production might be the ionic mechanisms for QT prolongation induced by THIO.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Cardiotoxicidade/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go/metabolismo , Tioridazina/toxicidade , Potenciais de Ação/fisiologia , Animais , Benzilaminas/farmacologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Estresse do Retículo Endoplasmático/genética , Canais de Potássio Éter-A-Go-Go/fisiologia , Células HEK293 , Proteínas de Choque Térmico HSP70/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sulfonamidas/farmacologia , Ubiquitinação
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