Abstract

Salmonella typhimuriuminfection is associated with gastrointestinal disorder and cellular injury in the liver of both humans and animals. Cinnamaldehyde, the main component of essential oil from cinnamon, has been reported to have anti-inflammatory, anti-oxidative, and anti-apoptotic effects. However, it remains unknown whether cinnamaldehyde can alleviateSalmonella typhimuriuminfection-induced liver injury in mice. In the present study, we found that cinnamaldehyde attenuatedSalmonella typhimurium-induced body weight loss, the increase of organ (liver and spleen) indexes, hepatocyte apoptosis, and the mortality rate in mice. Further study showed that cinnamaldehyde significantly alleviatedSalmonella typhimurium-induced liver injury as shown by activities of alanine transaminase, aspartate transaminase, and myeloperoxidase, as well as malondialdehyde. The increased mRNA level of pro-inflammatory cytokines (IL-1β,IL-6,TNF-α, andIFN-γ) and chemokines (CCL2andCCL3) induced bySalmonella typhimuriumwere significantly abolished by cinnamaldehyde supplementation. These alterations were associated with a regulatory effect of cinnamaldehyde onTLR2,TLR4, andMyD88. 16S rDNA sequence analysis showed thatSalmonella typhimuriuminfection led to upregulation of the abundances of generaAkkermansia,Bacteroides,Alistipes,Muribaculum, andPrevotellaceae UCG-001, and downregulation of the abundances of generaLactobacillus,Enterorhabdus, andEggerthellaceae(unclassified). These alterations were reversed by cinnamaldehyde supplementation. In conclusion, cinnamaldehyde attenuated the inflammatory response, oxidative stress, and apoptosis in the liver ofSalmonella typhimurium-infected mice. Supplementation of cinnamaldehyde might be a preventive strategy to alleviate liver injury caused bySalmonella typhimuriuminfection in humans and animals.Keywords:cinnamaldehyde;Salmonella typhimurium;mice;inflammation;apoptosis;oxidative stress;gut microbiota