Protective Roles of Sodium Selenite against Aflatoxin B1-Induced Apoptosis of Jejunum in Broilers

The effects of aflatoxin B-1 (AFB(1)) exposure and sodium selenite supplementation on cell apoptosis of jejunum in broilers were studied. A total of 240 one-day-old male AA broilers were randomly assigned four dietary treatments containing 0 mg/kg of AFB(1) (control), 0.3 mg/kg AFB(1) (AFB(1)), 0.4 mg/kg supplement Se (+ Se) and 0.3 mg/kg AFB(1) + 0.4 mg/kg supplement Se (AFB(1) + Se), respectively. Compared with the control broilers, the number of apoptotic cells, the expression of Bax and Caspase-3 mRNA were significantly increased, while the expression of Bcl-2 mRNA and the Bcl-2/Bax ratio were significantly decreased in AFB(1) broilers. The number of apoptotic cells and the expression of Caspase-3 mRNA in AFB(1) + Se broilers were significantly higher than those in the control broilers, but significantly lower than those in AFB(1) broilers. There were no significant changes in the expression of Bax mRNA between AFB(1) + Se and control broilers; the expression of Bcl-2 mRNA and the Bcl-2/Bax ratio in AFB(1) + Se broilers were significantly lower than those in the control broilers, but significantly higher than those in AFB(1) broilers. In conclusion, 0.3 mg/kg AFB(1) in the diet can increase cell apoptosis, decrease Bcl-2 mRNA expression, and increase of Bax and Caspase-3 mRNA expression in broiler's jejunum. However, supplementation of dietary sodium selenite at the concentration of 0.4 mg/kg Se may ameliorate AFB(1)-induced apoptosis by increasing Bcl-2 mRNA expression, and decreasing Bax and Caspase-3 mRNA expression.