Salvianolic acid B protects against sepsis-induced liver injury via activation of SIRT1/PGC-1[alpha] signaling

Liver injury occurs frequently during sepsis, which leads to high mortality and morbidity. A previous study has suggested that salvianolic acid B (SalB) is protective against sepsis-induced lung injury. However, whether SalB is able to protect against sepsis-induced liver injury remains unclear. The present study aimed to investigate the effects of SalB on sepsis-induced liver injury and its potential underlying mechanisms. Sepsis was induced in mice using a cecal ligation and puncture (CLP) method. The mice were treated with SalB (30 mg/kg intraperitoneally) at 0.5, 2 and 8 h after CLP induction. Pathological alterations of the liver were assessed using hematoxylin and eosin staining. The serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), tumor necrosis factor (TNF)-[alpha] and interleukin (IL)-6 were measured. The hepatic mRNA levels of TNF-[alpha], IL-6, Bax and Bcl-2 were also detected. The results suggested that treatment with SalB ameliorated sepsis-induced liver injury in the mice, as supported by the mitigated pathologic changes and lowered serum aminotransferase levels. SalB also decreased the levels of the inflammatory cytokines TNF-[alpha] and IL-6 in the serum and the liver of the CLP model mice. In addition, SalB significantly downregulated Bax expression and upregulated Bcl-2 expression, and upregulated the expression levels of SIRT1 and PGC-1[alpha]. However, when sirtuin 1 (SIRT1) small interfering RNA was co-administered with SalB, the protective effects of SalB were attenuated and the expression levels of SIRT1 and PGC-1[alpha] were reduced. In summary, these results indicate that SalB mitigates sepsis-induced liver injury via reduction of the inflammatory response and hepatic apoptosis, and the underlying mechanism may be associated with the activation of SIRT1/PGC-1[alpha] signaling. Key words: salvianolic acid B, sepsis, liver injury, SIRT1/PGC-1[alpha] signaling