Protective effects of pelargonidin on lipopolysaccharide-induced hepatic failure

Pelargonidin (PEL) is a well-known red pigment found in plants and has important biological activities that are potentially beneficial for human health. The aim of this study was to investigate the effect of PEL on lipopolysaccharide (LPS)-induced liver failure in mice, and to elucidate its underlying molecular mechanisms. Liver failure was induced by LPS (15 mg/kg, i.p.) in mice, and 12 h later, they were treated intravenously with PEL. Administration of LPS significantly increased mortality, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), and inflammatory cytokines, and expression of toll-like receptor 4 (TLR4) protein; PEL treatment effectively countered these effects of LPS. Further, LPS treatment markedly increased the expression of myeloid differentiation primary response gene 88 (MyD88), phosphorylation of p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), and expressions of nuclear proteins, such as nuclear factor (NF)-B and phosphorylated c-Jun. Additionally, LPS increased the serum levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6. All these effects of LPS were attenuated by PEL. In addition, the LPS-mediated increase in the level of serum interferon (IFN)-β expression of the TLR-associated activator of IFN (TRIF) protein, and phosphorylation of IFN regulatory factor 3 (IRF3) were reduced by PEL. Our results suggest that PEL attenuates LPS-induced liver damage by inhibition of the TLR-mediated inflammatory pathway and could be used to treat liver diseases.