RESUMEN
Oxyresveratrol (Oxy) is a natural polyhydroxystilbene abundant in mulberry that has anti-inflammation and anti-oxidant activities. We evaluated the protective effect of Oxy in the context of the lipopolysaccharide and d-galactosamine (LPS/d-GalN) induced acute liver injury. Oxy restricted the development of histopathological changes, markedly reduced the activity of alanine transaminase (ALT) and aspartate transaminase (AST), which are indicators of impaired liver function. Oxy significantly regulated the contents of oxidative stress related enzymes and products, and inhibited expressions of inflammatory mediators and cytokines. Oxy treatment diminished the Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway in liver, activated the Kelch-like ECH-associated protein 1(Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, and increased expressions of heme oxygenase 1 (HO-1) and quinine oxidoreductase 1(NQO1). Pretreatment with Oxy decreased LPS/d-GalN stimulated hepatocyte apoptosis by efficaciously raising the B-cell lymphoma 2 (Bcl-2)/Bcl-2 associated X (Bax) ratio, inhibiting the expression and activation of caspases, and activating the phosphoinoside-3-kinase (PI3K)-Akt pathway. Our results demonstrate the hepatoprotective efficacy of Oxy. The protection is mainly due to the prevention of TLR4/NF-κB pathway activation, induced activation of Keap1-Nrf2 signaling pathway, and decreased hepatocyte apoptosis. Oxy warrants further study as a potential therapeutic agent candidate for the management of acute liver injury.
Asunto(s)
Antiinflamatorios/uso terapéutico , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Hepatocitos/fisiología , Hígado/metabolismo , Extractos Vegetales/uso terapéutico , Estilbenos/uso terapéutico , Animales , Apoptosis , Células Cultivadas , Galactosamina/inmunología , Hemo-Oxigenasa 1/metabolismo , Hepatocitos/efectos de los fármacos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Lipopolisacáridos/inmunología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos , Morus/inmunología , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismoRESUMEN
To investigate the effects and mechanism of diosmetin on acute hepatic failure (AHF), an AHF murine model was established through administration of lipopolysaccharides/D-galactosamine (LPS/D-GalN). In vitro, diosmetin scavenged free radicals. In vivo, diosmetin decreased mortality among mice, blocked the development of histopathological changes and hepatic damage, and suppressed levels of inflammatory mediators and cytokines. In addition, diosmetin prevented the expression of phosphorylated IKK, IκBα, and NF-κB p65 in the NF-κB signaling pathway, and JNK and p38 in the MAPK signaling pathway. Diosmetin also inhibited hepatocyte apoptosis. Thus, diosmetin exerts protective effects against endotoxin-induced acute hepatic failure in mice. The underlying mechanisms are antioxidation, NF-κB signaling inhibition, inflammatory mediator/cytokine attenuation, and hepatocyte apoptosis suppression. Diosmetin is thus a potential drug candidate for use in the treatment of acute hepatic failure.