Hepatoprotective effect of anemoside B4 against sepsis-induced acute liver injury through modulating the mTOR/p70S6K-mediated autophagy

Abstract

Sepsis triggers liver dysfunction with high morbidity and mortality. Here, we elucidated the effect of anemoside B4 on sepsis in cecal ligation and puncture (CLP)-induced mouse model and LPS-induced primary hepatocytes. Following CLP surgery, septic mice were intraperitoneally injected with anemoside B4 (50 or 100 mg/kg). Anemoside B4 improved septic mouse survival rate, decreased serum AST and ALT levels and attenuated liver histopathologic damages. Western blot analysis showed that anemoside B4 elevated the expression of Beclin-1, LC3II/LC3I, Atg3, Atg5, and Atg7, and reduced p62, suggesting the restoration of autophagy flux in liver. More autophagic vesicles were observed in liver after anemoside B4 treatment using transmission electron microscopy. Using ELISA and commercial enzyme kits, we found that anemoside B4 decreased serum TNF-α, IL-6, and IL-1β levels and increased CAT, SOD and GSH activities. TUNEL staining and western blot revealed that anemoside B4 suppressed cell apoptosis, along with decreased Bax, leaved caspase-3, cleaved PARP, but increased Bcl-2. Consistent with in vivo findings, anemoside B4 inhibited apoptosis, inflammatory response, and oxidative stress and enhanced autophagy in LPS-induced primary hepatocytes. Importantly, these cellular processes were possibly mediated by mTOR/p70S6K signaling, as reflected by the offset of 3-MA in the immunosuppression of anemoside B4.