Proteomic analysis of toxic effects of short-term cadmium exposure on goat livers.

Food safety is closely related to environmental pollution. It is worth noting that the long-term accumulation of Cd, a toxic heavy metal, in animals may pose a threat to human health through food chain. Previous studies have found that Cd exposure may cause liver metabolic disorders of black goats, but the mechanism of its impact on liver proteome of goats has not been widely studied. Therefore, in this study, ten male goats (Nubian black goat × native black goat) were exposed to Cd via drinking water containing CdCl2 (20 mg Cd·kg - 1·BW) for 30 days (five male goats per group). Blood physiology and liver antioxidant indices in black goats were determined and differentially expressed proteins (DEPs) in the livers of Cd-exposed goats were profiled by using TMT-labelled proteomics. It was found that plasma Hb and RBC levels as well as PCV values were decreased, liver SOD, GSH-Px, T-AOC and CAT levels were decreased, and MDA level was increased in Cd-treated goats, and 630 DEPs (up 326, down 304) in the livers of Cd-treated goats. Proteomics analysis revealed that Cd exposure affected glutathione metabolism and drug metabolism-cytochrome P450. We identified GP×2, GSTM3, and TBXAS1 as potential protein markers of early Cd toxicity in goats. This study provided theoretical basis for early diagnosis of Cd poisoning in goats.