RESUMEN
BACKGROUND: Nuclear factor kappa B (NF-kappaB) is activated by several factors, which increase the inflammatory response, and this activation, in turn, leads to the expression of several genes such as cytokines, and may play an important role in cardiovascular diseases. AIMS: The aim of the study is to examine the effect of SUN C8079, a newly synthesized NF-kappaB inhibitor in vitro and in vivo. METHODS: We examined the effects of SUN C8079 on the transcriptional responses of NF-kappaB, on activation of NF-kappaB in electrophoretic mobility shift assay, and on the gene expressions of tumor necrosis factor (TNF)-alpha and iNOS. We also studied effects of SUN C8079 on lethal endotoxemia and viral myocarditis in mice. RESULTS: SUN C8079 inhibited the lipopolysaccharide (LPS)-induced expression of the genes of TNF-alpha and iNOS by inhibiting the activation of NF-kappaB in vitro. SUN C8079 inhibited the systemic release of TNF-alpha and improved mortality in LPS-treated mice. In addition to protecting mice against lethal endotoxemia, SUN C8079 prevented the development of myocarditis due to the encephalomyocarditis virus (EMCV), and inhibited the expressions of proinflammatory cytokines and the iNOS gene in cardiac tissues. CONCLUSION: These findings suggest that the activation of NF-kappaB plays an important role in the pathogenesis of endotoxemia and viral myocarditis, and that the NF-kappaB inhibitor, SUN C8079, may be therapeutic in these disorders.
Asunto(s)
Endotoxemia/prevención & control , Miocarditis/prevención & control , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico Sintasa/genética , Piperidinas/farmacología , Factor de Necrosis Tumoral alfa/genética , Animales , Infecciones por Cardiovirus/tratamiento farmacológico , Infecciones por Cardiovirus/prevención & control , Infecciones por Cardiovirus/virología , Núcleo Celular/metabolismo , Células Cultivadas , ADN Complementario/metabolismo , Virus de la Encefalomiocarditis , Endotoxemia/tratamiento farmacológico , Endotoxemia/etiología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Técnicas In Vitro , Interleucina-1/biosíntesis , Interleucina-1/genética , Lipopolisacáridos/toxicidad , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Miocarditis/tratamiento farmacológico , Miocarditis/virología , FN-kappa B/metabolismo , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa de Tipo II , Piperidinas/uso terapéutico , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
This study examined the gene expression of mouse mast cell proteases to clarify their role in the pathophysiology of viral myocarditis. Male DBA/2 mice were inoculated intraperitoneally with the encephalomyocarditis virus and the gene expression of mast cell chymase, mouse mast cell protease (mMCP)-4 and -5, and tryptase, mMCP-6, matrix metalloproteinase (MMP)-9 and type-I procollagen was measured by real-time quantitative RT-PCR analysis. The gene expression of mMCP-4, -5 and -6 mRNA was increased at 5 days, and continued to increase to day 14, coinciding with a prominent inflammatory reaction and extensive myocardial necrosis and fibrosis. The gene expression of MMP-9 was also increased, and there was a significant correlation between upregulation of mast cell proteases and MMP-9. The gene expression of type-I procollagen was increased at 5 days and continued to increase to day 14, suggesting that a fibrotic process had already begun during the acute stage of viral myocarditis. These findings suggest that mast cell chymase and tryptase participate in the acute inflammation and remodeling process of viral myocarditis.