RESUMEN
Calcium/calmodulin-dependent protein kinase II (CaMKII) has been demonstrated to be aberrantly activated in viral myocarditis (VMC), but the role of its subtype CaMKIIδ in VMC remains unclear.VMC mice and cardiomyocytes models were induced by Coxsackievirus B3 (CVB3) treatment. Mice that underwent sham surgery and saline-treated cardiomyocytes served as controls. Body weight, survival, left ventricular ejection fraction (LVEF), and fractional shortening (LVFS) were measured, and HE staining was performed to evaluate heart function in VMC mice model and sham control. Inflammation factors in serum or cell supernatant were detected by ELISA. Expressions of CaMKIIδ, Toll/interleukin-1 receptor domain containing adaptor protein (TIRAP), insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2), nuclear factor NF-kappaB (NF-κB) signals, and inflammation factors were examined by quantitative real time polymerase chain reaction (qRT-PCR) or western blot. CCK-8, EdU, and flow cytometry were used to evaluate cell behaviors. Co-immunoprecipitation (Co-IP), RNA immunoprecipitation (RIP), and RNA pull-down were utilized to validate molecule interaction. Methylated RNA immunoprecipitation (MeRIP) was performed to measure N6-methyladenosine (m6A) level of specific molecule.CaMKIIδ was upregulated in VMC mice and CVB3-treated primary cardiomyocytes, of which knockdown improved cell viability, proliferation, and suppressed cell apoptosis in vitro, thereby alleviating myocarditis in vivo. The stability of CaMKIIδ was attributed to the presence of IGF2BP2 through m6A modification. Loss of CaMKIIδ repressed NF-κB pathway via negatively and directly regulating TIRAP to be involved in inflammatory damage.CaMKIIδ, stabilized by m6A reader IGF2BP2, modulated NF-κB pathway via interacting with TIRAP to alter cell viability, proliferation, and apoptosis, thereby affecting VMC outcome.
Asunto(s)
Apoptosis , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Infecciones por Coxsackievirus , Modelos Animales de Enfermedad , Miocarditis , Miocitos Cardíacos , FN-kappa B , Proteínas de Unión al ARN , Receptores de Interleucina-1 , Transducción de Señal , Animales , Masculino , Ratones , Adenosina/análogos & derivados , Adenosina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proliferación Celular , Células Cultivadas , Infecciones por Coxsackievirus/metabolismo , Infecciones por Coxsackievirus/genética , Infecciones por Coxsackievirus/enzimología , Infecciones por Coxsackievirus/virología , Infecciones por Coxsackievirus/patología , Enterovirus Humano B/patogenicidad , Mediadores de Inflamación/metabolismo , Ratones Endogámicos BALB C , Miocarditis/metabolismo , Miocarditis/genética , Miocarditis/patología , Miocarditis/virología , Miocarditis/enzimología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/virología , FN-kappa B/metabolismo , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Función Ventricular IzquierdaRESUMEN
Obesity has been recognized as a major risk factor for the development of chronic cardiomyopathy, which is associated with increased cardiac inflammation, fibrosis, and apoptosis. We previously developed an anti-inflammatory compound C66, which prevented inflammatory diabetic complications via targeting JNK. In the present study, we have tested the hypothesis that C66 could prevent obesity-induced cardiomyopathy by suppressing JNK-mediated inflammation. High-fat diet (HFD)-induced obesity mouse model and palmitic acid (PA)-challenged H9c2 cells were used to develop inflammatory cardiomyopathy and evaluate the protective effects of C66. Our data demonstrate a protective effect of C66 against obesity-induced cardiac inflammation, cardiac hypertrophy, fibrosis, and dysfunction, overall providing cardio-protection. C66 administration attenuates HFD-induced myocardial inflammation by inhibiting NF-κB and JNK activation in mouse hearts. In vitro, C66 prevents PA-induced myocardial injury and apoptosis in H9c2 cells, accompanied with inhibition against PA-induced JNK/NF-κB activation and inflammation. The protective effect of C66 is attributed to its potential to inhibit JNK activation, which led to reduced pro-inflammatory cytokine production and reduced apoptosis in cardiomyocytes both in vitro and in vivo. In summary, C66 provides significant protection against obesity-induced cardiac dysfunction, mainly by inhibiting JNK activation and JNK-mediated inflammation. Our data indicate that inhibition of JNK is able to provide significant protection against obesity-induced cardiac dysfunction.
Asunto(s)
Antiinflamatorios/farmacología , Apoptosis/efectos de los fármacos , Compuestos de Bencilideno/farmacología , Cardiomiopatías/prevención & control , Ciclohexanonas/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Miocarditis/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Obesidad/complicaciones , Animales , Cardiomiopatías/enzimología , Cardiomiopatías/etiología , Cardiomiopatías/patología , Línea Celular , Citocinas/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos C57BL , Miocarditis/enzimología , Miocarditis/etiología , Miocarditis/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , FN-kappa B/metabolismo , Ácido Palmítico/toxicidad , Ratas , Transducción de SeñalRESUMEN
ABSTRACT: This study aimed to evaluate the protective effect of quercetin and its in-depth mechanism in TNF-α-stimulated cardiomyocytes. The differential expression of TNF-alpha (TNF-α) and signal transducer and activator of transcription 1 (STAT1) was analyzed based on the GEO database. H9c2 cells were stimulated with TNF-α to simulate myocarditis. Cell counting kit-8 assay and flow cytometry assay were performed to detect the cell viability and apoptosis. ELISA was used to measure the levels of proinflammatory cytokines (IL-6 and IL-17A) and anti-inflammatory cytokine (IL-10). STAT1 expression was downregulated by transfection with si-STAT1, and its expression was detected using quantitative real-time polymerase chain reaction and Western blot. Western blot was also performed to assess the expression of the mitogen-activated protein kinase (MAPK) pathway-related factors. In this article, TNF-α was highly expressed in patients with myocarditis, and TNF-α (20 µg/mL) declined the viability of H9c2 cells. Quercetin pretreatment partially alleviated the decrease of cell viability, the increase of apoptosis, and the release of inflammatory cytokines (IL-10, IL-6, and IL-17A) induced by TNF-α. In addition, TNF-α increased STAT1 expression, but quercetin prevented the TNF-α-increased STAT1 level. Remarkably, knockdown of STAT1 enhanced the protective effect of quercetin on TNF-α-injured H9c2 cells. Moreover, quercetin restrained the TNF-α-induced activation of the MAPK pathway. Also, the inhibitory effect of quercetin on the pathway was aggravated by STAT1 lacking. In summing, quercetin plays a protective role in TNF-α-stimulated H9c2 cell injury, which may be related to the regulation of STAT1 and MAPK pathway.
Asunto(s)
Antiinflamatorios/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Miocarditis/tratamiento farmacológico , Miocitos Cardíacos/efectos de los fármacos , Quercetina/farmacología , Factor de Transcripción STAT1/metabolismo , Animales , Estudios de Casos y Controles , Línea Celular , Humanos , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Miocarditis/enzimología , Miocarditis/genética , Miocarditis/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Ratas , Factor de Transcripción STAT1/genética , Transducción de Señal , Factor de Necrosis Tumoral alfa/toxicidadRESUMEN
A preclinical model of troponin I-induced myocarditis (AM) revealed a prominent role of the immunoproteasome (ip), the main immune cell-resident proteasome isoform, in heart-directed autoimmunity. Viral infection of the heart is a known trigger of cardiac autoimmunity, with the ip enhancing systemic inflammatory responses after infection with a cardiotropic coxsackievirusB3 (CV). Here, we used ip-deficient A/J-LMP7-/- mice to investigate the role of ip-mediated effects on adaptive immunity in CV-triggered myocarditis and found no alteration of the inflammatory heart tissue damage or cardiac function in comparison to wild-type controls. Aiming to define the impact of the systemic inflammatory storm under the control of ip proteolysis during CV infection, we targeted the ip in A/J mice with the inhibitor ONX 0914 after the first cycle of infection, when systemic inflammation has set in, well before cardiac inflammation. During established acute myocarditis, the ONX 0914 treatment group had the same reduction in cardiac output as the controls, with inflammatory responses in heart tissue being unaffected by the compound. Based on these findings and with regard to the known anti-inflammatory role of ONX 0914 in CV infection, we conclude that the efficacy of ip inhibitors for CV-triggered myocarditis in A/J mice relies on their immunomodulatory effects on the systemic inflammatory reaction.
Asunto(s)
Antiinflamatorios/farmacología , Infecciones por Coxsackievirus/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Células Mieloides/efectos de los fármacos , Miocarditis/tratamiento farmacológico , Miocitos Cardíacos/efectos de los fármacos , Oligopéptidos/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Animales , Células Cultivadas , Infecciones por Coxsackievirus/enzimología , Infecciones por Coxsackievirus/inmunología , Modelos Animales de Enfermedad , Enterovirus Humano B/inmunología , Enterovirus Humano B/patogenicidad , Interacciones Huésped-Patógeno , Inflamación/enzimología , Inflamación/inmunología , Inflamación/virología , Masculino , Ratones Noqueados , Células Mieloides/enzimología , Células Mieloides/inmunología , Células Mieloides/virología , Miocarditis/enzimología , Miocarditis/inmunología , Miocarditis/virología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/inmunología , Miocitos Cardíacos/virología , Complejo de la Endopetidasa Proteasomal/genética , ProteolisisRESUMEN
Myocardial inflammation has recently been recognized as a distinct feature of cardiac hypertrophy and heart failure. HectD3, a HECT domain containing E3 ubiquitin ligase has previously been investigated in the host defense against infections as well as neuroinflammation; its cardiac function however is still unknown. Here we show that HectD3 simultaneously attenuates Calcineurin-NFAT driven cardiomyocyte hypertrophy and the pro-inflammatory actions of LPS/interferon-γ via its cardiac substrates SUMO2 and Stat1, respectively. AAV9-mediated overexpression of HectD3 in mice in vivo not only reduced cardiac SUMO2/Stat1 levels and pathological hypertrophy but also largely abolished macrophage infiltration and fibrosis induced by pressure overload. Taken together, we describe a novel cardioprotective mechanism involving the ubiquitin ligase HectD3, which links anti-hypertrophic and anti-inflammatory effects via dual regulation of SUMO2 and Stat1. In a broader perspective, these findings support the notion that cardiomyocyte growth and inflammation are more intertwined than previously anticipated.
Asunto(s)
Cardiomegalia/metabolismo , Miocarditis/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Calcineurina/metabolismo , Cardiomegalia/enzimología , Cardiomegalia/prevención & control , Humanos , Inmunoprecipitación , Ratones , Microscopía Fluorescente , Miocarditis/enzimología , Miocarditis/prevención & control , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/metabolismo , Células RAW 264.7 , Ratas , Ratas Wistar , Factor de Transcripción STAT1/metabolismo , Transducción de Señal , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Sumoilación , Ubiquitina-Proteína Ligasas/fisiologíaRESUMEN
BACKGROUND: Genistein is widely used as a pharmacological compound as well as a food additive. However, the pharmaceutical effects of Genistein on myocarditis and its potential mechanisms have not been studied in detail. METHODS: H9c2 cells were continuously stimulated by lipopolysaccharide (LPS) for 12 h to simulate the in vitro model of myocarditis injury. DrugBank, String, and GEO dataset were used to investigate specific genes that interacting with Genistein. KEGG and GO enrichment analysis were employed to explore Myc-related signaling pathways. Biological behaviors of H9c2 cells were observed with the support of cell counting kit-8, MTT and flow cytometry. Expression levels of cytokines including TNF-α and ILs were evaluated by enzyme-linked immunosorbent assay. Western blot was applied to detect the expression of Myc and MAPK pathway related proteins. RESULTS: Genistein alleviated the damage of H9c2 cells subjected to LPS from the perspective of elevating cells growth ability, and inhibiting cells apoptosis and inflammatory response. Through bioinformatics analysis, we identified Myc as the potential target of Genistein in myocarditis, and MAPK as the signaling pathway. Significantly, Myc was highly up-regulated in myocarditis samples. More importantly, by performing biological experiments, we discovered that Genistein relieved H9c2 cells apoptosis and inflammatory reaction which caused by LPS stimulation through inhibiting Myc expression. Additionally, the marked augmentation of p-P38 MAPK and p-JNK expression in LPS-induced cardiomyocyte model were blocked by Genistein and si-Myc. CONCLUSIONS: Our research revealed that Myc mediated the protective effects of Genistein on H9c2 cells damage caused by LPS partly through modulation of MAPK/JNK signaling pathway.
Asunto(s)
Antiinflamatorios/farmacología , Genisteína/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Lipopolisacáridos/toxicidad , Miocarditis/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Miocarditis/enzimología , Miocarditis/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Fosforilación , Ratas , Transducción de SeñalRESUMEN
BACKGROUND: Previous studies have shown beneficial effects of acute infusion of the primary ketone body, ß-hydroxybutyrate, in heart failure (HF). However, whether chronic elevations in circulating ketones are beneficial remains unknown. METHODS: To chronically elevate circulating ketones in mice, we deleted the expression of the ketolytic, rate-limiting-enzyme, SCOT (succinyl-CoA:3-ketoacid-CoA transferase 1; encoded by Oxct1), in skeletal muscle. Tamoxifen-inducible skeletal muscle-specific Oxct1Muscle-/- knockout (n=32) mice and littermate controls (wild type; WT; n=35) were subjected to transverse aortic constriction (TAC) surgery to induce HF. RESULTS: Deletion of SCOT in skeletal, but not cardiac muscle resulted in elevated concentrations of fasted circulating ß-hydroxybutyrate in knockout mice compared with WT mice (P=0.030). Five weeks following TAC, WT mice progressed to HF, whereas knockout mice with elevated fasting circulating ketones were largely protected from the TAC-induced effects observed in WT mice (ejection fraction, P=0.011; mitral E/A, P=0.012). Furthermore, knockout mice with TAC had attenuated expression of markers of sterile inflammation and macrophage infiltration, which were otherwise elevated in WT mice subjected to TAC. Lastly, addition of ß-hydroxybutyrate to isolated hearts was associated with reduced NLRP3 (nucleotide-binding domain-like receptor protein 3)-inflammasome activation, which has been previously shown to play a role in contributing to HF-induced cardiac inflammation. CONCLUSIONS: These data show that chronic elevation of circulating ketones protects against the development of HF that is associated with the ability of ß-hydroxybutyrate to directly reduce inflammation. These beneficial effects of ketones were associated with reduced cardiac NLRP3 inflammasome activation, suggesting that ketones may modulate cardiac inflammation via this mechanism.
Asunto(s)
Ácido 3-Hidroxibutírico/sangre , Coenzima A Transferasas/deficiencia , Insuficiencia Cardíaca/prevención & control , Miocarditis/prevención & control , Miocardio/enzimología , Animales , Coenzima A Transferasas/genética , Modelos Animales de Enfermedad , Fibrosis , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/enzimología , Insuficiencia Cardíaca/fisiopatología , Hipertrofia Ventricular Izquierda/sangre , Hipertrofia Ventricular Izquierda/fisiopatología , Hipertrofia Ventricular Izquierda/prevención & control , Inflamasomas/metabolismo , Preparación de Corazón Aislado , Masculino , Ratones Noqueados , Miocarditis/sangre , Miocarditis/enzimología , Miocarditis/fisiopatología , Miocardio/patología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Regulación hacia Arriba , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/prevención & control , Función Ventricular Izquierda , Remodelación VentricularRESUMEN
BACKGROUND: Viral myocarditis (VMC) is a type of cardiac inflammation that is generally caused by coxsackievirus B3 (CVB3) infection. Several MicroRNAs (miRNAs) are known to play crucial roles in VMC pathogenesis. MiR-15 is reportedly associated with myocardial injury, inflammatory responses and viral infection. Whether miR-15 affects the occurrence and development of VMC remains largely unknown. The roles of miR-15 and their underlying mechanisms in CVB3-stimulated H9c2 cells were assessed in this study. METHODS: We infected H9c2 cells with CVB3 to establish a VMC cellular model. We then determined the effects of miR-15 inhibition on three cardiomyocyte injury markers: lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin-I (cTn-I). The impact on CVB3-induced cell apoptosis and pro-inflammatory cytokines was also investigated. The effects of miR-15 inhibition on NLRP3 inflammasome activation were also assessed. The target relationship between miR-15 and NOD-like receptor X1 (NLRX1) was determined using a luciferase reporter assay. RESULTS: MiR-15 expression was significantly upregulated in H9c2 cells after CVB3 infection. Inhibition of miR-15 significantly decreased the CVB3-induced levels of LDH, CK-MB and cTn-I. It also elevated cell viability, reduced CVB3-induced cell apoptosis and decreased the generation of the interleukins IL-1ß, IL-6 and IL-18. Furthermore, we determined that miR-15 inhibition suppressed NLRP3 inflammasome activation by downregulating NLRP3 and caspase-1 p20 expression. We found a direct target relationship between miR-15 and NLRX1. Additionally, inhibition of NLRX1 reversed the protective effects of miR-15 inhibition against CVB3-induced myocardial cell injury by regulating the NLRP3 inflammasome. CONCLUSION: Our results indicate that miR-15 inhibition alleviates CVB3-induced myocardial inflammation and cell injury. This may be partially due to NLRX1-mediated NLRP3 inflammasome inactivation.
Asunto(s)
Apoptosis/genética , Infecciones por Coxsackievirus/metabolismo , Inflamasomas/metabolismo , Inflamación/metabolismo , Miocarditis/metabolismo , Miocitos Cardíacos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Animales , Línea Celular , Supervivencia Celular/genética , Infecciones por Coxsackievirus/genética , Forma MB de la Creatina-Quinasa/metabolismo , Citocinas/metabolismo , Inflamación/genética , L-Lactato Deshidrogenasa/metabolismo , Miocarditis/enzimología , Miocarditis/genética , Miocarditis/virología , Miocitos Cardíacos/enzimología , Ratas , Regulación hacia ArribaRESUMEN
Viral myocarditis is caused by a viral infection and characterized by the inflammation of the myocardium. Coxsackievirus B3 (CVB3) infection is one of the most common among the infections caused by this virus. The host's early innate immune response to CVB3 infection particularly depends on the functions of type I interferons (IFNs). In this study, we report that a host microRNA, miR-30a, was upregulated by CVB3 to facilitate its replication. We demonstrated that miR-30a was a potent negative regulator of IFN-I signaling by targeting tripartite motif protein 25 (TRIM25). In addition, we found that TRIM25 overexpression significantly suppressed CVB3 replication, whereas TRIM25 knockdown increased viral titer and VP1 protein expression. MiR-30a inhibits the expression of TRIM25 and TRIM25-mediated retinoic acid-inducible gene (RIG)-I ubiquitination to suppress IFN-ß activation and production, thereby resulting in the enhancement of CVB3 replication. These results indicate the proviral role of miR-30a in modulating CVB3 infection for the first time. This not only provides a new strategy followed by CVB3 in order to modulate IFN-I-mediated antiviral immune responses by engaging host miR-30a but also improves our understanding of its pathogenesis.
Asunto(s)
Infecciones por Coxsackievirus/virología , Enterovirus Humano B/crecimiento & desarrollo , Interferón beta/metabolismo , MicroARNs/metabolismo , Miocarditis/virología , Factores de Transcripción/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Replicación Viral , Animales , Proteínas de la Cápside/metabolismo , Infecciones por Coxsackievirus/enzimología , Infecciones por Coxsackievirus/genética , Infecciones por Coxsackievirus/inmunología , Proteína 58 DEAD Box/metabolismo , Enterovirus Humano B/inmunología , Enterovirus Humano B/metabolismo , Células HEK293 , Células HeLa , Interacciones Huésped-Patógeno , Humanos , Interferón beta/genética , Ratones Endogámicos BALB C , MicroARNs/genética , Miocarditis/enzimología , Miocarditis/genética , Miocarditis/inmunología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/inmunología , Miocitos Cardíacos/virología , Receptores Inmunológicos/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Regulación hacia ArribaRESUMEN
OBJECTIVE: To investigate whether phenylephrine (PE) inhibits sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury through the PI3K/Akt signaling pathway. METHODS: A rat model of sepsis was established by cecal ligation and puncture. PE and/or wortmannin (a PI3K inhibitor) were administered to investigate the role of PI3K/Akt signaling in mediating the effects of PE on inhibiting sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury. Hematoxylin-eosin staining, echocardiography, and Langendorff system were used to examine the myocardial injury and function. The concentrations of TNF-α and IL-6 were analyzed by enzyme-linked immunosorbent assay. Intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), myeloperoxidase, mitochondria-related fusion/fission proteins, and PI3K/Akt signaling pathway-associated proteins were analyzed by Western blotting. RESULTS: PE improved the cardiac function and survival in septic rats. PE decreased TNF-α, IL-6, ICAM-1, VCAM-1, and myeloperoxidase contents in the myocardium of septic rats. Meanwhile, PE increased the fusion-related proteins and decreased the fission-related proteins in the myocardial mitochondria of septic rats. On the other hand, PE activated the PI3K/Akt signaling pathway in the cecal ligation and puncture-treated rats, and all the protective effects of PE were abolished by wortmannin. CONCLUSIONS: PE attenuated sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury through the PI3K/Akt signaling pathway.
Asunto(s)
Mitocondrias Cardíacas/efectos de los fármacos , Dinámicas Mitocondriales/efectos de los fármacos , Miocarditis/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Fenilefrina/farmacología , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sepsis/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Mediadores de Inflamación/metabolismo , Preparación de Corazón Aislado , Masculino , Mitocondrias Cardíacas/enzimología , Mitocondrias Cardíacas/patología , Proteínas Mitocondriales/metabolismo , Miocarditis/enzimología , Miocarditis/etiología , Miocarditis/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Peroxidasa/metabolismo , Ratas Sprague-Dawley , Sepsis/complicaciones , Transducción de Señal , Volumen Sistólico/efectos de los fármacos , Función Ventricular IzquierdaRESUMEN
AIMS: To investigate whether there exists a cardio-protective effect of Fasudil, a selective Rho kinase (ROCK) inhibitor, in an experimental murine model of acute viral myocarditis. METHODS: Male BALB/c mice were randomly assigned to three groups: control, myocarditis treated with placebo and myocarditis treated with Fasudil (n = 40 animals per group). Myocarditis was established by intraperitoneal injection with coxsackievirus B3 (CVB3). Twenty-four hours after infection, Fasudil was intraperitoneally administered for 14 consecutive days. Twenty mice were randomly selected from each group to monitor a 14-day survival rate. On day 7 and day 14, eight surviving mice from each group were sacrificed and their hearts and blood were obtained to perform serological and histological examinations. Expression of ROCKs, IL-17, IL-1b, TNFα, RORgt, and Foxp3 were quantified with RT-PCR. Plasma levels of TNF alpha, IL-1 beta, and IL-17 were measured by ELISA. In addition, protein levels of IL-17 and ROCK2 in cardiac tissues were analyzed with Western blot. RESULTS: Fasudil treatment significantly increased survival, attenuated myocardial necrotic lesions, reduced CVB3 replication and expression of ROCK2 and IL-17 in the infected hearts. This treatment also imposed a T-cell subpopulation shift, from Th17 to Treg, in cardiac tissues. CONCLUSIONS: ROCK pathway inhibition was cardio-protective in viral myocarditis with increased survival, decreased viral replication, and inflammatory response. These findings suggest that Fasudil might be a potential therapeutic agent for patients with viral myocarditis.
Asunto(s)
1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Antiinflamatorios/farmacología , Antivirales/farmacología , Infecciones por Coxsackievirus/prevención & control , Enterovirus Humano B/efectos de los fármacos , Miocarditis/prevención & control , Miocardio/enzimología , Inhibidores de Proteínas Quinasas/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Infecciones por Coxsackievirus/enzimología , Infecciones por Coxsackievirus/patología , Infecciones por Coxsackievirus/virología , Citocinas/sangre , Modelos Animales de Enfermedad , Enterovirus Humano B/crecimiento & desarrollo , Mediadores de Inflamación/sangre , Masculino , Ratones Endogámicos BALB C , Miocarditis/enzimología , Miocarditis/patología , Miocarditis/virología , Miocardio/patología , Necrosis , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/virología , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Células TH1/virología , Carga Viral , Replicación Viral/efectos de los fármacos , Quinasas Asociadas a rho/metabolismoRESUMEN
In the cardiomyocyte, CaMKII has been identified as a nodal influencer of excitation-contraction and also excitation-transcription coupling. Its activity can be regulated in response to changes in intracellular calcium content as well as after several post-translational modifications. Some of the effects mediated by CaMKII may be considered adaptive, while effects of sustained CaMKII activity may turn into the opposite and are detrimental to cardiac integrity and function. As such, CaMKII has long been noted as a promising target for pharmacological inhibition, but the ubiquitous nature of CaMKII has made it difficult to target CaMKII specifically where it is detrimental. In this review, we provide a brief overview of the physiological and pathophysiological properties of CaMKII signaling, but we focus on the physiological and adaptive functions of CaMKII. Furthermore, special consideration is given to the emerging role of CaMKII as a mediator of inflammatory processes in the heart.
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Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cardiomiopatía Chagásica/enzimología , Mediadores de Inflamación/metabolismo , Miocarditis/enzimología , Miocardio/enzimología , Animales , Apoptosis , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/química , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Cardiomiopatía Chagásica/genética , Cardiomiopatía Chagásica/patología , Cardiomiopatía Chagásica/fisiopatología , Activación Enzimática , Regulación Enzimológica de la Expresión Génica , Humanos , Miocarditis/genética , Miocarditis/patología , Miocarditis/fisiopatología , Miocardio/patología , Necrosis , Conformación Proteica , Transducción de Señal , Relación Estructura-ActividadRESUMEN
BACKGROUND: Diastolic dysfunction (DD), a hallmark of obesity and primary defect in heart failure with preserved ejection fraction, is a predictor of future cardiovascular events. We previously reported that linagliptin, a dipeptidyl peptidase-4 inhibitor, improved DD in Zucker Obese rats, a genetic model of obesity and hypertension. Here we investigated the cardioprotective effects of linagliptin on development of DD in western diet (WD)-fed mice, a clinically relevant model of overnutrition and activation of the renin-angiotensin-aldosterone system. METHODS: Female C56Bl/6 J mice were fed an obesogenic WD high in fat and simple sugars, and supplemented or not with linagliptin for 16 weeks. RESULTS: WD induced oxidative stress, inflammation, upregulation of Angiotensin II type 1 receptor and mineralocorticoid receptor (MR) expression, interstitial fibrosis, ultrastructural abnormalities and DD. Linagliptin inhibited cardiac DPP-4 activity and prevented molecular impairments and associated functional and structural abnormalities. Further, WD upregulated the expression of TRAF3IP2, a cytoplasmic adapter molecule and a regulator of multiple inflammatory mediators. Linagliptin inhibited its expression, activation of its downstream signaling intermediates NF-κB, AP-1 and p38-MAPK, and induction of multiple inflammatory mediators and growth factors that are known to contribute to development and progression of hypertrophy, fibrosis and contractile dysfunction. Linagliptin also inhibited WD-induced collagens I and III expression. Supporting these in vivo observations, linagliptin inhibited aldosterone-mediated MR-dependent oxidative stress, upregulation of TRAF3IP2, proinflammatory cytokine, and growth factor expression, and collagen induction in cultured primary cardiac fibroblasts. More importantly, linagliptin inhibited aldosterone-induced fibroblast activation and migration. CONCLUSIONS: Together, these in vivo and in vitro results suggest that inhibition of DPP-4 activity by linagliptin reverses WD-induced DD, possibly by targeting TRAF3IP2 expression and its downstream inflammatory signaling.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Cardiomiopatías/prevención & control , Dieta Occidental/efectos adversos , Dipeptidil Peptidasa 4/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Linagliptina/farmacología , Miocarditis/prevención & control , Miocardio/enzimología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Cardiomiopatías/enzimología , Cardiomiopatías/etiología , Cardiomiopatías/fisiopatología , Células Cultivadas , Diástole , Modelos Animales de Enfermedad , Regulación hacia Abajo , Femenino , Fibrosis , Ratones Endogámicos C57BL , Miocarditis/enzimología , Miocarditis/etiología , Miocarditis/fisiopatología , Miocardio/ultraestructura , FN-kappa B/metabolismo , Estrés Nitrosativo/efectos de los fármacos , Obesidad/etiología , Estrés Oxidativo/efectos de los fármacos , Recuperación de la Función , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Factor de Transcripción AP-1/metabolismo , Disfunción Ventricular Izquierda/enzimología , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/prevención & control , Función Ventricular Izquierda/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
OBJECTIVE: To observe the effect of QiShenYiQi pill (QSYQ) on myocardial collagen metabolism in experimental autoimmune myocarditis rats, and to explore its mechanism of action. METHODS: Lewis rats underwent the injection of myocardial myosin mixed with freund's complete adjuvant were randomized into three groups: model, valsartan and QSYQ groups. And we treated rats which were injected phosphate buffered saline (PBS) mixed with freund's complete adjuvant as control group. Rats were intervened and euthanized at 4 and 8 weeks. We use alkaline hydrolysis to detect the content of myocardial hydroxyproline (HYP), and ELISA to detect the level of serum procollagen type I carboxyterminal peptide (PICP), procollagen type III amino-terminal peptide (PIIINP), and collagen C telopeptide type I (CTX-I). Myocardial MMP-1 and TIMP-1 protein expression was detected by immunohistochemistry, and myocardial MMP-1 and TIMP-1 mRNA expression was detected by real-time qPCR. RESULTS: QSYQ reduced the content of myocardial HYP, and this reduction was greater over time. QSYQ also reduced the serum concentration of PICP, PIIINP, CTX-I and the PICP/PIIINP ratio, which further reduced over time, whereas its effect on lowering PICP was significantly greater than that of valsartan at 4 and 8 weeks, and lowering CTX-I was significantly greater than that of valsartan at 8 weeks. In addition, after 4 weeks, QSYQ enhanced the protein and mRNA expression of MMP-1 and TIMP-1, and its effect on highering TIMP-1 was significantly greater than that of valsartan, whereas there was no significant difference in the expression of myocardial MMP-1 or TIMP-1 at 8 weeks. QSYQ reduced the ratio of MMP-1/TIMP-1, which further reduced over time, and the effect of QYSQ was significantly greater than that of valsartan after 4 weeks. CONCLUSION: This study provides evidence that QSYQ can reduce the rate of myocardial collagen synthesis and degradation. It also effectively improved the degree of myocardial fibrosis in experimental autoimmune myocarditis rats and it had a tendency to have a greater effect with longer treatment duration, which is related to the mechanism of regulation of MMP-1 and TIMP-1 expression in the myocardial rat.
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Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/metabolismo , Colágeno/metabolismo , Medicamentos Herbarios Chinos/uso terapéutico , Miocarditis/tratamiento farmacológico , Miocarditis/metabolismo , Animales , Enfermedades Autoinmunes/enzimología , Medicamentos Herbarios Chinos/farmacología , Hidroxiprolina/metabolismo , Masculino , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Miocarditis/enzimología , Miocardio/enzimología , Miocardio/metabolismo , Miocardio/patología , Proteolisis/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Endogámicas Lew , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-1/metabolismoRESUMEN
OBJECTIVE: To compare the changes in muscle enzyme between children with myocarditis and Duchene/Becker muscular dystrophy (DMD/BMD), and to seek the explanations for variation.â© METHODS: The retrospective analysis for 83 myocarditis children (myocarditis group) and 69 DMD/BMD children (DMD/BMD group), who were collected from Department of Pediatric of Shengjing Hospital affiliated to China Medical University since January 2008 to May 2015, was carried out. At the same time, 24 healthy children from the Department of Pediatric Development served as a control group. The examination indexes included creatine kinase (CK), creatine kinase-isoenzyme MB (CK-MB), creatine kinase isoenzyme MB mass (CK-MB mass), cardiac troponin I (cTnI) and high-sensitive-cTnT (hs-cTnT).â© RESULTS: 1) In the myocarditis group, the CK increased from 100 to 1 000 U/L, reached a peak after 5 days, which lasted for a week and then dropped to the normal; the CK-MB reached a peak after 5 to 7 days and dropped to the normal a month later; the CK-MB mass reached a peak on the first day and dropped to the normal after 3 weeks; the cTn reached to a peak after 5 days and dropped to the normal after about 17 days; hs-cTnT reached to a peak on the first day and dropped to the normal after about 19 days. 2) In the DMD/BMD group, the CK increased significantly and 27 cases had a CK value of more than 10 000 U/L. After the treatment for 1 to 2 weeks, their enzyme rose again after a slight drop. In terms of cTnI, 6 cases showed a moderate increase, 5 of them couldn't drop to the normal level until more than 3 weeks later; the hs-cTnT increased in the 45 cases, which lasted for more than 3 weeks in the 31 cases of them and showed a tendency of persisting increase.â© CONCLUSION: The cTnI and hs-cTnT rise significantly and possess wider observation window than CK and CK-MB mass in myocarditis children, with more sensitive and specific changes. The myocardial damage can occur before myasthenia and keep this trend for a long time in the DMD/BMD children. The trend of cTnI change in myocarditis children is similar to hs-cTnT, while hs-cTnT in DMD/BMD children is more sensitive than cTnI.
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Forma MB de la Creatina-Quinasa/metabolismo , Creatina Quinasa/metabolismo , Distrofia Muscular de Duchenne/enzimología , Miocarditis/enzimología , Troponina I/metabolismo , Troponina T/metabolismo , Biomarcadores , Niño , China , Creatina Quinasa/sangre , Forma MB de la Creatina-Quinasa/sangre , Femenino , Humanos , Masculino , Debilidad Muscular/enzimología , Distrofia Muscular de Duchenne/terapia , Miocarditis/terapia , Estudios Retrospectivos , Factores de Tiempo , Troponina I/sangre , Troponina T/sangreRESUMEN
BACKGROUND: Myocarditis, characterized by myocyte necrosis, fibrosis, and degeneration with mononuclear cell infiltration, always causes heart failure in patients. Phosphoinositide 3-kinase (PI3K) is a pivotal kinase known to regulate inflammatory responses in cardiac diseases. Although previous research has suggested that PI3K was involved in cardiac diseases such as myocardial infarction, it is still unclear whether the inhibition of PI3K is essential for the treatment of myosin-induced myocarditis. The aim of this study was to explore whether pharmacological blockade of PI3K is able to protect mice against experimental autoimmune myocarditis (EAM). MATERIALS AND METHODS: We used the cardiac myosin-induced murine EAM model to investigate the therapeutic effect of PI3K inhibitor LY294002 on autoimmune myocarditis in mice. RESULTS: LY294002 significantly alleviated EAM injury in mice, as indicated by the reduction of cardiac necrosis, inflammatory infiltrates, and CD3(+) T cells. LY294002 also decreased the expression of p-Akt upon cardiac myosin treatment in the cardiac tissue of the mice. In the present study, LY294002 resulted in a moderate reduction in absolute CD4(+) cell numbers and a significant decrease in the absolute numbers of CD8(+) cells. Consequently, LY294002 increased the CD4(+)/CD8(+) ratio compared with peptide treatment alone. CONCLUSION: This report provides evidence that PI3K inhibitor LY294002 has potent effects against cardiac injury caused by EAM, suggesting that it has therapeutic value for the treatment of myocarditis.
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Enfermedades Autoinmunes/tratamiento farmacológico , Cromonas/uso terapéutico , Morfolinas/uso terapéutico , Miocarditis/tratamiento farmacológico , Inhibidores de las Quinasa Fosfoinosítidos-3 , Animales , Enfermedades Autoinmunes/enzimología , Enfermedades Autoinmunes/etiología , Enfermedades Autoinmunes/patología , Cromonas/farmacología , Citocinas/sangre , Evaluación Preclínica de Medicamentos , Femenino , Inmunización , Ratones , Ratones Endogámicos BALB C , Morfolinas/farmacología , Miocarditis/enzimología , Miocarditis/etiología , Miocarditis/patología , Miocardio/inmunología , Miocardio/patología , Cadenas Pesadas de Miosina/inmunología , Cadenas Pesadas de Miosina/toxicidad , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/toxicidad , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas c-akt/metabolismo , Miosinas Ventriculares/inmunología , Miosinas Ventriculares/toxicidadRESUMEN
Mammalian target of rapamycin (mTOR) is an evolutionary conserved kinase that senses the nutrient and energy status of cells, the availability of growth factors, stress stimuli and other cellular and environmental cues. It responds by regulating a range of cellular processes related to metabolism and growth in accordance with the available resources and intracellular needs. mTOR has distinct functions depending on its assembly in the structurally distinct multiprotein complexes mTORC1 or mTORC2. Active mTORC1 enhances processes including glycolysis, protein, lipid and nucleotide biosynthesis, and it inhibits autophagy. Reported functions for mTORC2 after growth factor stimulation are very diverse, are tissue and cell-type specific, and include insulin-stimulated glucose transport and enhanced glycogen synthesis. In accordance with its cellular functions, mTOR has been demonstrated to regulate cardiac growth in response to pressure overload and is also known to regulate cells of the immune system. The present manuscript presents recently obtained insights into mechanisms whereby mTOR may change anabolic, catabolic and stress response pathways in cardiomocytes and discusses how mTOR may affect inflammatory cells in the heart during hemodynamic stress. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
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Cardiomegalia/enzimología , Mediadores de Inflamación/metabolismo , Miocarditis/enzimología , Miocitos Cardíacos/enzimología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/genética , Cardiomegalia/patología , Cardiomegalia/fisiopatología , Fármacos Cardiovasculares/farmacología , Humanos , Miocarditis/tratamiento farmacológico , Miocarditis/genética , Miocarditis/patología , Miocarditis/fisiopatología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Biosíntesis de Proteínas , Inhibidores de Proteínas Quinasas/farmacología , Proteolisis , Transducción de Señal , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/genética , Remodelación VentricularRESUMEN
Fenofibrate (FF), as a peroxisome-proliferator-activated receptor α (PPARα) agonist, has been used clinically for decades to lower lipid levels. In the present study, we examined whether FF can be repurposed to prevent the pathogenesi of the heart in Type 1 diabetes and to describe the underlying mechanism of its action. Streptozotocin (STZ)-induced diabetic mice and their age-matched control mice were treated with vehicle or FF by gavage every other day for 3 or 6 months. FF prevented diabetes-induced cardiac dysfunction (e.g. decreased ejection fraction and hypertrophy), inflammation and remodelling. FF also increased cardiac expression of fibroblast growth factor 21 (FGF21) and sirtuin 1 (Sirt1) in non-diabetic and diabetic conditions. Deletion of FGF21 gene (FGF21-KO) worsened diabetes-induced pathogenic effects in the heart. FF treatment prevented heart deterioration in the wild-type diabetic mice, but could not do so in the FGF21-KO diabetic mice although the systemic lipid profile was lowered in both wild-type and FGF21-KO diabetic mice. Mechanistically, FF treatment prevented diabetes-impaired autophagy, reflected by increased microtubule-associated protein 1A/1B-light chain 3, in the wild-type diabetic mice but not in the FGF21-KO diabetic mice. Studies with H9C2 cells in vitro demonstrated that exposure to high glucose (HG) significantly increased inflammatory response, oxidative stress and pro-fibrotic response and also significantly inhibited autophagy. These effects of HG were prevented by FF treatment. Inhibition of either autophagy by 3-methyladenine (3MA) or Sirt1 by sirtinol (SI) abolished FF's prevention of HG-induced effects. These results suggested that FF could prevent Type 1 diabetes-induced pathological and functional abnormalities of the heart by increasing FGF21 that may up-regulate Sirt1-mediated autophagy.
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Autofagia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Cardiomiopatías Diabéticas/prevención & control , Fenofibrato/farmacología , Factores de Crecimiento de Fibroblastos/metabolismo , Miocarditis/prevención & control , Miocardio/enzimología , Sirtuina 1/metabolismo , Remodelación Ventricular/efectos de los fármacos , Animales , Glucemia/metabolismo , Línea Celular , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/enzimología , Diabetes Mellitus Tipo 1/patología , Cardiomiopatías Diabéticas/enzimología , Cardiomiopatías Diabéticas/etiología , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/fisiopatología , Factores de Crecimiento de Fibroblastos/deficiencia , Factores de Crecimiento de Fibroblastos/genética , Fibrosis , Inhibidores de Histona Desacetilasas/farmacología , Hipertrofia Ventricular Izquierda/enzimología , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Izquierda/prevención & control , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Miocarditis/enzimología , Miocarditis/etiología , Miocarditis/patología , Miocarditis/fisiopatología , Miocardio/patología , Estrés Oxidativo/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
UNLABELLED: Viral myocarditis, which is most prevalently caused by coxsackievirus B3 (CVB3), is a serious clinical condition characterized by excessive myocardial inflammation. Recent studies suggest that regulation of protein acetylation levels by inhibiting histone deacetylase (HDAC) activity modulates inflammatory response and shows promise as a therapy for several inflammatory diseases. However, the role of HDAC activity in viral myocarditis is still not fully understood. Here, we aim to investigate the role of HDAC activity in viral myocarditis and its underlying mechanism. CVB3-infected BALB/c mice were treated with the HDAC inhibitor (HDACI) suberoylanilide hydroxamic acid (SAHA) or trichostatin A (TSA). We found inhibition of HDAC activity aggravated rather than ameliorated the severity of CVB3-induced myocarditis, which was contrary to our expectations. The aggravated myocarditis by HDACI treatment seemed not to be caused by an elevated inflammatory response but by the increased CVB3 replication. Further, it was revealed that the increased CVB3 replication was closely associated with the HDACI-enhanced autophagosome formation. Inhibition of autophagosome formation by wortmannin or ATG5 short hairpin RNA dramatically suppressed the HDACI-increased CVB3 replication. The increased viral replication subsequently elevated CVB3-induced myocardial apoptosis. Conversely, inhibition of CVB3 replication and ensuing myocardial apoptosis by the antiviral drug ribavirin significantly reversed the HDACI-aggravated viral myocarditis. In conclusion, we elucidate that the inhibition of HDAC activity increases CVB3 replication and ensuing myocardial apoptosis, resulting in aggravated viral myocarditis. Possible adverse consequences of administering HDACI should be considered in patients infected (or coinfected) with CVB3. IMPORTANCE: Viral myocarditis, which is most prevalently caused by CVB3, is characterized by excessive myocardial inflammation. Inhibition of HDAC activity was originally identified as a powerful anti-cancer therapeutic strategy and was recently found to be implicated in the regulation of inflammatory response. HDACI has been demonstrated to be efficacious in animal models of several inflammatory diseases. Thus, we hypothesize that inhibition of HDAC activity also protects against CVB3-induced viral myocarditis. Surprisingly, we found inhibition of HDAC activity enhanced myocardial autophagosome formation, which led to the elevated CVB3 viral replication and ensuing increased myocardial apoptosis. Viral myocarditis was eventually aggravated rather than ameliorated by HDAC inhibition. In conclusion, we elucidate the role of HDAC activity in viral myocarditis. Moreover, given the importance of HDACI in preclinical and clinical treatments, the possible unfavorable effect of HDACI should be carefully evaluated in patients infected with viruses, including CVB3.
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Infecciones por Coxsackievirus/virología , Enterovirus Humano B/patogenicidad , Inhibidores de Histona Desacetilasas/efectos adversos , Histona Desacetilasas/genética , Miocarditis/virología , Replicación Viral/efectos de los fármacos , Androstadienos/farmacología , Animales , Antivirales/farmacología , Apoptosis/efectos de los fármacos , Proteína 5 Relacionada con la Autofagia , Infecciones por Coxsackievirus/enzimología , Infecciones por Coxsackievirus/genética , Infecciones por Coxsackievirus/patología , Modelos Animales de Enfermedad , Enterovirus Humano B/efectos de los fármacos , Enterovirus Humano B/fisiología , Regulación de la Expresión Génica , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/efectos adversos , Ácidos Hidroxámicos/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos BALB C , Proteínas Asociadas a Microtúbulos/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Miocarditis/enzimología , Miocarditis/genética , Miocarditis/patología , Miocardio/enzimología , Miocardio/patología , Fagosomas/química , Fagosomas/efectos de los fármacos , Fagosomas/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ribavirina/farmacología , Replicación Viral/genética , Vorinostat , WortmaninaRESUMEN
RATIONALE: The development of molecular imaging approaches that assess specific immunopathologic mechanisms can advance the study of myocarditis. OBJECTIVE: This study validates a novel molecular imaging tool that enables the in vivo visualization of granzyme B activity, a major effector of cytotoxic CD8+ T lymphocytes. METHODS AND RESULTS: We synthesized and optimized a fluorogenic substrate capable of reporting on granzyme B activity and examined its specificity ex vivo in mice hearts with experimental cytotoxic CD8+ T lymphocyte-mediated myocarditis using fluorescence reflectance imaging, validated by histological examination. In vivo experiments localized granzyme B activity in hearts with acute myocarditis monitored by fluorescent molecular tomography in conjunction with coregistered computed tomography imaging. A model anti-inflammatory intervention (dexamethasone administration) in vivo reduced granzyme B activity (vehicle versus dexamethasone: 504±263 versus 194±77 fluorescence intensities in hearts; P=0.002). CONCLUSIONS: Molecular imaging of granzyme B activity can visualize T cell-mediated myocardial injury and monitor the response to an anti-inflammatory intervention.