The Antagonistic Effects of Selenium Yeast (SeY) on Cadmium-Induced Inflammatory Factors and the Heat Shock Protein Expression Levels in Chicken Livers

Cadmium (Cd) is a ubiquitous toxic heavy metal in the natural environment that can cause multiple organ damage to the bodies of animals and humans. Selenium yeast (SeY) is a kind of organic selenium (Se) that has a very strong function against Cd-induced injury to tissues or organs. The aim of the current study was to investigate the roles of inflammatory factors and heat shock proteins (HSPs) in inflammatory injury triggered by Cd and to analyze the protective effects of SeY on Cd-induced damnification in the livers of chickens. Two hundred 120-day-old layers were randomly divided into four groups and raised on a conventional diet, or with Se (0.5 mg/kg SeY), Cd (150 mg/kg CdCl₂), or Se + Cd (0.5 mg/kg SeY and 150 mg/kg CdCl₂) in their basic diets for 120 days. Then, the liver histopathology, production of nitric oxide (NO), activity of inducible NO synthase (iNOS), and mRNA and protein expression levels of inflammatory factors (iNOS, NF-κB, TNF-α, and PTGE) and heat shock proteins (HSPs 27, 40, 60, 70, and 90) were examined. The results showed that exposure to Cd obviously increased Cd accumulation, NO production, iNOS activity, inflammatory factor, and HSP mRNA and protein expression levels and further caused an inflammatory response. Supplementation with SeY had an antagonistic effect on Cd-induced inflammatory injury in chicken livers. Thus, the present study suggests that SeY can be taken as a potential therapeutic for Cd-induced liver inflammatory injury in chickens.