Trans-anethole ameliorates lipopolysaccharide-induced acute liver inflammation in broilers via inhibiting NF-κB signaling pathway

The aim of this study was to investigate the protective effect of trans-anethole (TA) on lipopolysaccharide-induced acute liver inflammation model of chickens by determining the levels of inflammatory mediators in serum and liver, relative mRNA expression and protein expression of inflammation-related genes in NF-κB signaling pathway. A total of 160 one-day-old male chickens (Arbor Acres) were assigned into 4 treatments with 8 replicates of 5 birds each. On d 20, the control group was intraperitoneally injected with sterile saline and the other groups were injected with lipopolysaccharide (LPS; 5 mg/kg body weight). There were no significant differences in average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) among groups. However, compared with the control group, the LPS group significantly increased (P < 0.01) the serum levels of interleukin-6 (IL-6), interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and decreased (P < 0.01) the interleukin-10 (IL-10) level. TA attenuated (P < 0.01) these increases in IL-1β, TNF-α, ALT, and AST levels and improved (P < 0.01) the IL-10 level. In liver, the groups fed with TA had lower (P < 0.01) concentrations of IL-6 and TNF-α as well as higher (P < 0.05) concentration of IL-10. Furthermore, TA downregulated (P < 0.05) the mRNA expression levels of nuclear factor kappa B p65 (NF-κB p65) and TNF-α, also upregulated (P < 0.05) IL-10 and inhibitor of NF-κB alpha (IκBα) upon LPS challenge. In protein level, supplementation of 600 mg/kg of TA downregulated (P < 0.05) and upregulated (P < 0.05) the protein expression of NF-κB p65 and IκBα, respectively. The present findings suggest that TA could alleviate the acute liver inflammation induced by LPS via blocking the activation of NF-κB and the 600 mg/kg of TA plays more fruitful role in protecting broilers against LPS stimulus.