Combined effects of deoxynivalenol and zearalenone on oxidative injury and apoptosis in porcine splenic lymphocytes in vitro

Deoxynivalenol (DON) and zearalenone (ZEA) are the two most common mycotoxins in animal feed. In this study, we examined oxidative injury and apoptosis of porcine splenic lymphocytes induced by DON or ZEA and their combination in vitro. Based on IC₅₀ values, porcine splenic lymphocytes were treated with 0.06, 0.3, 1.5, and 7.5 μg/mL DON, 0.08, 0.4, 2, and 10 μg/mL ZEA, or both DON and ZEA at 0.06 and 0.08 μg/mL, 0.3 and 0.4 μg/mL, and 1.5 and 2 μg/mL, respectively. After 48 h of DON and/or ZEA exposure, the cells were analyzed for antioxidant functions, apoptosis, and mRNA and protein expression of apoptosis-related genes p53, Bcl-2, Bax, caspase-3, and caspase-8 to determine their apoptosis and oxidative damage effects and mechanisms. The results showed that, compared with the control group, SOD, CAT, GPx, GSH, and Bcl-2 mRNA and protein expression levels were significantly reduced in exposed groups (P < 0.05 or P < 0.01). Furthermore, MDA contents, apoptosis rates, and p53, Bax, caspase-3 and caspase-8 protein and mRNA expression levels were increased significantly (P < 0.01). The effects of DON and ZEA were dose dependent and synergistic in combination. These data suggest that DON and ZEA induce oxidative damage and apoptosis of porcine splenic lymphocytes.