RESUMO
CYJ-27, a synthetic analog of decursin, prevents the generation of proinflammatory cytokines and oxidative stress. In this study, the effects of CYJ-27 on the regulation of inducible nitric oxide synthase (iNOS), heme oxygenase (HO)-1, and cyclooxygenase (COX-)2 were characterized in lipopolysaccharide (LPS)-treated human umbilical vein endothelial cells (HUVECs). In addition, the effects of CYJ-27 on the production of iNOS and representative proinflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, were tested in the lung tissues of LPS-treated mice. CYJ-27 promoted the expression of HO-1, suppressed NF-κB-luciferase activity, and reduced COX-2/PGE2 and iNOS/NO, resulting in a diminution in phosphorylated-STAT-1. Furthermore, CYJ-27 promoted the nuclear translocation of Nrf2, enhanced the combination of Nrf2 to antioxidant response elements, and diminished IL-1ß production in LPS-activated HUVECs. CYJ-27-downregulated iNOS/NO expression was rescued after the RNAi suppression of HO-1. In LPS-treated mice, CYJ-27 significantly diminished iNOS production in the lung tissues and TNF-α expression in the bronchoalveolar lavage fluid. These findings indicate that CYJ-27 exerts anti-inflammatory activities by regulating iNOS through downregulation of both NF-κB activation and phosphorylated-STAT-1. Hence, it can act as a template for the development of novel substances to treat inflammatory diseases.
Assuntos
Inflamação , NF-kappa B , Animais , Benzopiranos , Butiratos , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/genética , Lipopolissacarídeos , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismoRESUMO
The global incidence of Mycobacterium abscessus (Mabc), a rapidly growing nontuberculous mycobacterial strain that causes treatment-refractory pulmonary diseases, is increasing. Despite this, the host factors that allow for protection against infection are largely unknown. In this study, we found that sirtuin 3 (SIRT3), a mitochondrial protein deacetylase, plays a critical role in host defense against Mabc infection. Mabc decreased SIRT3 and upregulated mitochondrial oxidative stress in macrophages. SIRT3 deficiency led to increased bacterial loads, histopathological, and mitochondrial damage, and pathological inflammation during Mabc infection. Administration of scavengers of mitochondrial reactive oxygen species significantly decreased the in vivo Mabc burden and excessive inflammation, and induced SIRT3 expression in infected lungs. Notably, SIRT3 agonist (resveratrol) significantly decreased Mabc growth and attenuated inflammation in mice and zebrafishes, indicating the key role for SIRT3 in metazoan host defense. Collectively, these data strongly suggest that SIRT3 is a host-directed therapeutic target against Mabc infection by controlling mitochondrial homeostasis.
