The Metabolism of Arsenobetaine in Antarctic Krill Oil in Rats

Abstract:

To study the absorption, distribution, and accumulation of arsenobetaine in Antarctic krill (Euphausia superba) oil, Wistar rats were randomly divided into 3 groups and treated with 2.625 g/kg·bw of soybean oil, krill oil, or 100 mg/kg arsenobetaine added to krill oil. The plasma, liver, kidney and spleen of the rats were collected at 1 h, 2 h, 4 h, 6 h, 12 h, and 24 h after gavage, whereas the urine was also collected at 12 h and 24 h. The total arsenic content in the plasma, organs, and urine was detected by ICP-MS. The total arsenic contents in liver and kidney of rats were also measured at 7 d and 30 d after continuous gavage with the same dose of the lipids. The total arsenic contents in the plasma and organs showed no obvious changes at each time point between the krill oil group and the control group. The maximum content of total arsenic in plasma occurred at 1 h after gavage, whereas the total arsenic content in the liver, kidney, and spleen were all the highest at 6 h after gavage. At 24 h after gavage, the content of total arsenic in the liver, kidney, and spleen decreased to below 30% of the maximum. Within 24 h, 85% of the arsenic in the krill oil was passed out of the body in the urine. After continuous gavage for 7 days and 30 days, the total arsenic contents in the liver and kidney of the rats in each group showed no significant changes when compared with those of the control group. Arsenobetaine in the krill oil was rarely absorbed in rats and most passed out of the body in the urine within 24 h. No cumulative effects appeared after long-term feeding with the krill oil and the arsenobetaine.