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1.
Front Cardiovasc Med ; 11: 1342686, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562191

RESUMO

Background: Iron deficiency (ID) is the most common nutritional deficiency, with little research on its prevalence and long-term outcomes in the general population and those with heart failure (HF). Both the relationships between dietary iron and ID, as well as dietary folate and ID, are understudied. Methods: We used data from the National Health and Nutrition Examination Survey from 1999 to 2002 to investigate the prevalence, prognosis, and relationship between dietary and ID defined by different criteria in the general population (n = 6,660) and those with HF (n = 182). Results: There was no significant difference in the prevalence of ID between HF patients and the general population after propensity score matching. Transferrin saturation (TSAT) <20% was associated with higher 5-year all-cause mortality (HR: 3.49, CI: 1.40-8.72, P = 0.007), while ferritin <30 ng/ml was associated with higher 10-year (HR: 2.70, CI: 1.10-6.67, P = 0.031) and 15-year all-cause mortality (HR: 2.64, CI: 1.40-5.00, P = 0.003) in HF patients. Higher dietary total folate but dietary iron reduced the risk of ID (defined as ferritin <100 ng/ml) in HF patients (OR: 0.80; 95% CI: 0.65-1.00; P = 0.047). Conclusions: The prevalence of ID was identical in HF and non-HF individuals. Ferritin <30 ng/ml was associated with long-term outcomes whereas TSAT <20% was associated with short-term prognosis in both the general population and HF patients. A diet rich in folate might have the potential for prevention and treatment of ID in HF patients.

2.
Biochem Biophys Res Commun ; 704: 149702, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38422898

RESUMO

BACKGROUND: As a chronic inflammatory disease, diabetes mellitus (DM) contributes to the development of atherosclerosis (AS). However, how the NLRP3 inflammasome participates in diabetes-related AS remains unclear. Therefore, this study aimed to elucidate the mechanism through which NLRP3 uses high glucose (HG) levels to promote AS. METHODS: Serum and coronary artery tissues were collected from coronary artery disease (CAD) patients with and without DM, respectively. The expression of NLRP3 was detected, and the effects of this inflammasome on diabetes-associated AS were evaluated using streptozotocin (STZ)-induced diabetic apoE-/- mice injected with Adenovirus-mediated NLRP3 interference (Ad-NLRP3i). To elucidate the potential mechanism involved, ox-LDL-irritated human aortic smooth muscle cells were divided into the control, high-glucose, Si-NC, and Si-NLRP3 groups to observe the changes induced by downregulating NLRP3 expression. For up-regulating NLRP3, control and plasmid contained NLRP3 were used. TNF-α, IL-1ß, IL-6, IL-18, phosphorylated and total p38, JNK, p65, and IκBα expression levels were detected following the downregulation or upregulation of NLRP3 expression. RESULTS: Patients with comorbid CAD and DM showed higher serum levels and expression of NLRP3 in the coronary artery than those with only CAD. Moreover, mice in the Ad-NLRP3i group showed markedly smaller and more stable atherosclerotic lesions compared to those in other DM groups. These mice had decreased inflammatory cytokine production and improved glucose tolerance, which demonstrated the substantial effects of NLRP3 in the progression of diabetes-associated AS. Furthermore, using the siRNA or plasmid to downregulate or upregulate NLRP3 expression in vitro altered cytokines and the MAPK/NF-κB pathway. CONCLUSIONS: NLRP3 expression was significantly increased under hyperglycemia. Additionally, it accelerated AS by promoting inflammation via the IL/MAPK/NF-κB pathway.


Assuntos
Aterosclerose , Diabetes Mellitus Experimental , Humanos , Camundongos , Animais , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Camundongos Knockout para ApoE , Inflamação/metabolismo , Aterosclerose/complicações , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Glucose
3.
Pacing Clin Electrophysiol ; 46(9): 1035-1048, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37573146

RESUMO

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.


Assuntos
Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Cirurgia Assistida por Computador , Humanos , Eletrofisiologia Cardíaca , Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Cirurgia Assistida por Computador/métodos , Resultado do Tratamento
4.
Front Cardiovasc Med ; 9: 1037176, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386380

RESUMO

Over the last few decades, catheter ablation has emerged as the first-line treatment for ventricular arrhythmias. However, detailed knowledge of cardiac anatomy during the surgery remains the prerequisite for successful ablation. Intracardiac echocardiography (ICE) is a unique imaging technique, which provides real-time visualization of cardiac structures, and is superior to other imaging modalities in terms of precise display of cardiac tissue characteristics as well as the orientation of anatomical landmarks. This article aimed to introduce the various advantages and limitations of ICE in the ablation of ventricular arrhythmias.

5.
Cells ; 11(17)2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-36078037

RESUMO

Atrial fibrillation (AF) is a form of sustained cardiac arrhythmia and microRNAs (miRs) play crucial roles in the pathophysiology of AF. To identify novel miR-mRNA pairs, we performed RNA-seq from atrial biopsies of persistent AF patients and non-AF patients with normal sinus rhythm (SR). Differentially expressed miRs (11 down and 9 up) and mRNAs (95 up and 82 down) were identified and hierarchically clustered in a heat map. Subsequently, GO, KEGG, and GSEA analyses were run to identify deregulated pathways. Then, miR targets were predicted in the miRDB database, and a regulatory network of negatively correlated miR-mRNA pairs was constructed using Cytoscape. To select potential candidate genes from GSEA analysis, the top-50 enriched genes in GSEA were overlaid with predicted targets of differentially deregulated miRs. Further, the protein-protein interaction (PPI) network of enriched genes in GSEA was constructed, and subsequently, GO and canonical pathway analyses were run for genes in the PPI network. Our analyses showed that TNF-α, p53, EMT, and SYDECAN1 signaling were among the highly affected pathways in AF samples. SDC-1 (SYNDECAN-1) was the top-enriched gene in p53, EMT, and SYDECAN1 signaling. Consistently, SDC-1 mRNA and protein levels were significantly higher in atrial samples of AF patients. Among negatively correlated miRs, miR-302b-3p was experimentally validated to suppress SDC-1 transcript levels. Overall, our results suggested that the miR-302b-3p/SDC-1 axis may be involved in the pathogenesis of AF.


Assuntos
Fibrilação Atrial , MicroRNAs , Fibrilação Atrial/patologia , Átrios do Coração/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , Proteína Supressora de Tumor p53
6.
Front Cardiovasc Med ; 9: 937758, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935646

RESUMO

Double-chambered right ventricle (DCRV) is a rare congenital heart defect in adults, manifesting with progressive right ventricular outflow tract obstruction. We describe the first case of DCRV coexisting with hypertrophic cardiomyopathy, which is complicated by atrial flutter. A middle-aged woman with recurrent symptomatic atrial flutter who had previously been diagnosed with biventricular hypertrophic cardiomyopathy was admitted to our department. Echocardiography and cardiac magnetic resonance revealed asymmetrical interventricular septal hypertrophy, and abnormal muscle bundles within the right ventricle, generating an obstructive gradient. Genetic testing detected a hypertrophic cardiomyopathy-associated mutation: MYH7, c.4135G > A, p. Ala1379Thr. A diagnosis of DCRV complicated by hypertrophic cardiomyopathy and atrial flutter was made. Surgical intervention was performed, which included radiofrequency ablation, removal of abnormal muscle bundles, and ventricular septal defect repair. Intraoperative transesophageal echocardiography demonstrated the well-corrected right ventricular outflow tract. Free of early postoperative complications, the patient was discharged in sinus rhythm on the 11th day after the surgery. Unfortunately, the patient died from a sudden death 38 days following the surgery. In conclusion, the coexistence of DCRV with hypertrophic cardiomyopathy in patients is an uncommon condition. The present case highlights the importance of diagnostic imaging in the management of this disorder.

7.
J Card Surg ; 37(9): 2766-2775, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35726669

RESUMO

Left atrial appendage closure (LAAC) is an effective means of preventing ischemic stroke in patients with nonvalvular atrial fibrillation. Transesophageal echocardiography (TEE) is the primary imaging technique to guide LAAC. Its shortcomings, namely the use of general anesthesia and tracheal intubation, inevitably increase procedural risks. Intracardiac echocardiography (ICE), a novel imaging modality for guiding LAAC, has proven more advantageous over TEE due to use of local anesthesia, shortened procedural time, and reduced radiation exposure. This review highlights the differences between ICE and TEE guided LAAC, aiming to provide a reference for clinical decision-making.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Cateterismo Cardíaco/métodos , Ecocardiografia Transesofagiana , Humanos , Valor Preditivo dos Testes , Resultado do Tratamento
8.
Heart Surg Forum ; 24(5): E801-E807, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34623252

RESUMO

BACKGROUND: Although epicardial adipose tissue (EAT) has been proven to be related to atrial fibrillation (AF) and post-ablation AF recurrence, the association between EAT and AF after cardiac surgery (AFACS) remains unclear. OBJECTIVE: This study was a systematic review and meta-analysis that assessed the relationship between EAT and AFACS. METHODS: Electronic databases were systematically searched for "atrial fibrillation" and "epicardial adipose tissue." The analysis was stratified according to the EAT measurement into three meta-analyses as (1) total EAT volume, (2) left atrial (LA)-EAT volume, and (3) EAT thickness. Standardized mean difference (SMD) was estimated using a random effects model. RESULTS: Eight articles with 10 studies (546 patients) were included. The meta-analysis revealed that EAT was higher in those with AFACS irrespective of the EAT measurement (total EAT volume: SMD = 0.56 mL, 95% confidence interval, CI = 0.56-1.10 mL, I2 = 0.90, P = .04; EAT thickness: SMD = 0.85 mm, 95% CI = 0.04-1.65 mm, I2 = 0.90, P = .04; LA-EAT volume: SMD = 0.57 mL, 95% CI = 0.23-0.92 mL, I2 = 0.00, P = .001). CONCLUSION: EAT was higher in patients with AFACS, measured either as volume or thickness.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Pericárdio/diagnóstico por imagem , Fibrilação Atrial/diagnóstico , Humanos , Fatores de Risco , Tomografia Computadorizada por Raios X
9.
Pacing Clin Electrophysiol ; 44(7): 1207-1215, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34101856

RESUMO

BACKGROUND: Left atrial appendage occlusion (LAAO) is usually performed via the guidance of procedural transesophageal echocardiography (TEE) companied by general anesthesia (GA). OBJECTIVE: To investigate the feasibility and safety of LAAO guided by procedural fluoroscopy only. METHODS: The patients eligible for LAAO were enrolled into the current study and received implantation of either Watchman device or LAmbre device. The procedure was carried out with procedural fluoroscopy only and no companied GA; the position, shape, and leakage of the device were assessed by contrast angiography. TEE was performed after 3-month follow-up to evaluate the thrombosis, and leakage of device. RESULTS: Ninety-seven patients with atrial fibrillation (AF) with either Watchman device (n = 49) or LAmbre device (n = 48) were consecutively enrolled. Watchman device group was of lower CHA2 DS2 -VASc and HAS-BLED scores compared with LAmbre device groups (p < .05); the two groups had similar distributions of other baseline characteristics (p > .05), including procedural success rate (98.0% vs. 97.9%), mean procedure time, mean fluoroscopy time, total radiation dose, contrast medium dose, percentage of peri-device leakage. Pericardial effusions requiring intervention occurred in two of the Watchman group. TEE follow-up found no patient with residual leakage ≥5 mm at 3 months and no device related thrombosis (DRT). During the 22.0 ± 11.1 months follow-up, two patients experienced ischemic stroke. CONCLUSIONS: LAAO with the procedural imaging of fluoroscopy only exhibited the promising results of efficacy and safety. A prospective randomized multicenter study would be required to verify the observations in this study.


Assuntos
Apêndice Atrial/cirurgia , Fibrilação Atrial/cirurgia , Fluoroscopia , Cirurgia Assistida por Computador , Idoso , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Estudos de Viabilidade , Feminino , Fluoroscopia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cirurgia Assistida por Computador/efeitos adversos
10.
BMC Cardiovasc Disord ; 20(1): 219, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32397961

RESUMO

BACKGROUND: Atrioesophageal fistula (AEF) is the most fatal complication associated with catheter ablation for atrial fibrillation and cannot be easily detected when thoracic contrast-enhanced computed tomography (CT) is normal. CASE PRESENTATION: In this report, we described a diagnostic tool for detecting AEF with doubtful chest CT in which we introduced CO2-insufflation esophageal endoscopy with transthoracic echocardiography monitoring. Using this modified esophageal endoscopy, AEF was established due to the presence of both esophageal lesions and bubbles into the left atrium. That way, our patient accepted to be operated in time with good clinical prognosis. CONCLUSIONS: This modified esophageal endoscopy is an alternative tool for early detection of AEF when normal or doubtful CT findings present.


Assuntos
Dióxido de Carbono/administração & dosagem , Ecocardiografia , Embolia Aérea/prevenção & controle , Fístula Esofágica/diagnóstico , Esofagoscopia , Fístula/diagnóstico , Cardiopatias/diagnóstico , Doença Iatrogênica , Insuflação , Dióxido de Carbono/efeitos adversos , Ablação por Cateter/efeitos adversos , Diagnóstico Precoce , Ecocardiografia/efeitos adversos , Embolia Aérea/etiologia , Fístula Esofágica/etiologia , Fístula Esofágica/cirurgia , Esofagoscopia/efeitos adversos , Fístula/etiologia , Fístula/cirurgia , Cardiopatias/etiologia , Cardiopatias/cirurgia , Humanos , Insuflação/efeitos adversos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
11.
J Interferon Cytokine Res ; 40(1): 64-69, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31584315

RESUMO

Epicardial adipose tissue (EAT) is associated with the pathogenesis of atrial fibrillation (AF). The role of local inflammation in persistent AF is unclear. The purpose of this study was to assess the relationship between regional interleukin-1ß (IL-1ß) and persistent AF. Thirty-seven persistent AF patients underwent coronary artery bypass grafting surgery were enrolled. Patients without a history of AF (n = 37), but received the same surgery matched by age, gender, and body mass index, were enrolled in the control group. EAT thickness was measured by echocardiography. We obtained blood and EAT samples at open-heart surgery. In each patient, serum and EAT levels of IL-1ß and adiponectin were measured. The EAT thickness in patients with persistent AF was significantly greater than that in the control group (5.6 ± 1.1 versus 5.0 ± 1.3 mm, P = 0.02). The mRNA level of IL-1ß was higher in persistent AF group than the control group (4.94 ± 1.69 versus 2.93 ± 0.91, P < 0.01). Adiponectin expression decreased in persistent AF patients (7.04 ± 2.21 versus 8.63 ± 2.95, P = 0.01). There were no significant differences in plasma levels of IL-1ß and adiponectin between the 2 groups. Multiple logistic regression analysis showed that IL-1ß was an independent risk factor of persistent AF. These findings suggested that regional IL-1ß in EAT was an independent risk factor of persistent AF, which may promote the persistence of AF. [Figure: see text].


Assuntos
Tecido Adiposo/metabolismo , Fibrilação Atrial/sangue , Interleucina-1beta/sangue , Pericárdio/metabolismo , Tecido Adiposo/patologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Humanos , Inflamação/sangue , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/genética , Pessoa de Meia-Idade , Pericárdio/patologia , RNA Mensageiro/sangue , RNA Mensageiro/genética , Análise de Regressão , Fatores de Risco
12.
J Cell Mol Med ; 22(9): 4344-4353, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29971943

RESUMO

Atrial myocyte hypertrophy is one of the most important substrates in the development of atrial fibrillation (AF). The TWEAK/Fn14 axis is a positive regulator of cardiac hypertrophy in cardiomyopathy. This study therefore investigated the effects of Fn14 on atrial hypertrophy and underlying cellular mechanisms using HL-1 atrial myocytes. In patients with AF, Fn14 protein levels were higher in atrial myocytes from atrial appendages, and expression of TWEAK was increased in peripheral blood mononuclear cells, while TWEAK serum levels were decreased. In vitro, Fn14 expression was up-regulated in response to TWEAK treatment in HL-1 atrial myocytes. TWEAK increased the expression of ANP and Troponin T, and Fn14 knockdown counteracted the effect. Inhibition of JAK2, STAT3 by specific siRNA attenuated TWEAK-induced HL-1 atrial myocytes hypertrophy. In conclusion, TWEAK/Fn14 axis mediates HL-1 atrial myocytes hypertrophy partly through activation of the JAK2/STAT3 pathway.


Assuntos
Fibrilação Atrial/genética , Cardiomegalia/genética , Citocina TWEAK/genética , Janus Quinase 2/genética , Miócitos Cardíacos/metabolismo , Fator de Transcrição STAT3/genética , Receptor de TWEAK/genética , Idoso , Animais , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Estudos de Casos e Controles , Citocina TWEAK/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Miócitos Cardíacos/patologia , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Receptor de TWEAK/antagonistas & inibidores , Receptor de TWEAK/metabolismo , Troponina T/genética , Troponina T/metabolismo
13.
Med Sci Monit ; 22: 1250-7, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27078001

RESUMO

BACKGROUND Plumbagin is a potent antioxidant with anti-inflammatory and anti-carcinogenic action. Myocardial ischemia/reperfusion injury results in organ damage through oxidative stress and inflammatory mechanisms. In this study, we analyzed the potential role of plumbagin against myocardial I/R injury in Wistar rats. MATERIAL AND METHODS Oxidative stress was measured through ROS, lipid peroxide content, and antioxidant enzyme activities. The expression of redox signaling and inflammatory proteins was analyzed through Western blotting. Inflammatory cytokine expressions were determined through ELISA. RESULTS Oxidative stress status was reduced by plumbagin by decreasing ROS and lipid peroxide levels in rats with myocardial I/R (MI/R) injury. Plumbagin regulated redox imbalance induced by I/R injury by modulating the transcription factors NF-κB and Nrf-2. Further, downstream targets of NF-κB (COX-2, iNOS) and Nrf-2 (HO-1, NQO1 and GST) expression were significantly downregulated by plumbagin treatment. Pro-inflammatory cytokine expressions were significantly abrogated by plumbagin treatment. CONCLUSIONS This study shows the protective role of plumbagin against myocardial I/R injury by regulating antioxidant and inflammatory mechanisms.


Assuntos
Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Naftoquinonas/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Anticarcinógenos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
14.
Ann Med ; 47(4): 316-24, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25982799

RESUMO

Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice and a major cause of morbidity and mortality. Although the fundamental mechanisms underlying AF remain incompletely understood, atrial remodeling, including structural, electrical, contractile, and autonomic remodeling, has been demonstrated to contribute to the substrate for AF maintenance. Accumulating evidence shows that tumor necrosis factor alpha (TNF-α) plays exceedingly important roles in atrial remodeling. This article reviews recent advances in the roles of TNF-α in the pathogenesis of AF, elucidates the related mechanisms, and exploits its potential usefulness as a novel therapeutic target.


Assuntos
Fibrilação Atrial/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/fisiologia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/etiologia , Fibrilação Atrial/patologia , Autofagia/fisiologia , Biomarcadores/metabolismo , Humanos , Terapia de Alvo Molecular , Fator de Necrose Tumoral alfa/uso terapêutico
15.
Int J Clin Exp Pathol ; 7(10): 6514-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25400729

RESUMO

An immerging role of TNF-α in collagen synthesis and cardiac fibrosis implies the significance of TNF-α production in the development of myocardial remodeling. Our previous study showed a reduction of TNF-α and attenuated cardiac remodeling in CXCR6 knockout (KO) mice after ischemia/reperfusion injury. However, the potential mechanism of TNF-α-mediated cardiac fibrosis with pressure overload has not been well elucidated. In the present study, we aim to investigate the role of CXCR6 in TNF-α release and myocardial remodeling in response to pressure overload. Pressure overload was performed by constriction of transverse aorta (TAC) surgery on CXCR6 KO mice and C57 wild-type (WT) counterparts. At 6 weeks after TAC, cardiac remodeling was assessed by echocardiography, cardiac TNF-α release and its type I receptor (TNFRI), were detected by ELISA and western blot, collagen genes Col1a1 (type I) and Col3a1 (type III) were examined by real-time PCR. Compared with CXCR6 WT mice, CXCR6 KO mice exhibited less cardiac dysfunction, reduced expression of TNFRI, Col1a1 and Col3a. In vitro, we confirmed that CXCR6 deficiency led to reduced homing and infiltration of CD11b(+) monocytes, which contributed to attenuated TNF-α release in myocardium. Furthermore, TNFRI antagonist pretreatment blocked AT1 receptor signaling and NOX4 expression, reduced collagen synthesis, and blunted the activity of MMP9 in CXCR6 WT mice after TAC, but these were not observed in CXCR6 KO mice. In the present work, we propose a mechanism that CXCR6 is essential for pressure overload-mediated myocardial recruitment of monocytes, which contributes to cardiac fibrosis through TNF-α-dependent MMP9 activation and collagen synthesis.


Assuntos
Quimiotaxia de Leucócito , Cardiopatias/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Monócitos/metabolismo , Miocárdio/metabolismo , Receptores CXCR/deficiência , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Remodelação Ventricular , Animais , Antígeno CD11b/metabolismo , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Ativação Enzimática , Fibrose , Cardiopatias/genética , Cardiopatias/imunologia , Cardiopatias/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Miocárdio/imunologia , Miocárdio/patologia , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Receptores CXCR/genética , Receptores CXCR6 , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo
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