Investigation on DNA damage of mouse mononuclear cells in peripheral blood induced by low-dose T-2 toxin and deoxynivalenol alone or in combination

Abstract

Objective To investigate the characteristics and extent of mononuclear ceils DNA damage in peripheral blood of mice fed with low dose T-2 toxin and Deoxynivalenol(DON) alone or in combination and to explore the long-term toxicity of the toxin at sub-clinical dose. Methods Eighty female Balb/c mice weighing (14.0 ± 1.5)g 3 weeks after birth were divided randomly into control group, T-2 toxin group, DON group and T-2 toxin combined with DON group according to their body weight, 20 in each group. The mice were injected intraperitoneally T-2 toxin(5 μg·kg-1·d-1), DON(20 μg·kg-1·d-1), T-2 toxin(5 μg·kg-1·d-1) combined with:DON (20μg·kg-1·d-1)respectively,control group were treated by isotonic NaCl. In 16 weeks and 21 weeks of exposure, the tail blood of the mice was collected. The comet rate, tail DNA content,tail length and tail extent moment of mouse mononuclear ceils in peripheral blood was observed using single cell gel electrophoresis(SCGE). Results ① In T-2 toxin group,tail DNA content,tail length and tail extent moment were (27.71 ± 15.85)%, (13.67 ± 5.56)μm, 4.26 ± 3.83 at 16 weeks and (28.38 ± 15.57)%, (13.83 ± 5.47)μm, 4.37 ± 3.82 at 21 weeks, all levels of the indexes increased. In the control group, the corresponding values were (11.87 ± 4.61)%, (10.59±6.70)μm, 1.34±0.98 at 16 weeks and (11.31 ± 3.94)%, (10.83 ± 7.05)μm, 1.29±1.01 at 21 weeks, the differences in the two groups were significant (all P < 0.05) ;②In DON group, the comet rate of cells, tail DNA content and tail extent moment of comet ceils were 5.62%, (28.13 ±13.31)%, 3.39 ± 2.35 at 16 weeks and 7.71%, (29.17 ± 15.12)%, 5.70 ± 4.17 at 21 weeks. In the control group, the tailing rate was 4.34% at 16 weeks and 4.38% at 21 weeks, the differences in the two groups were significant (all P < 0.05);③In the group of T-2 toxin combined with DON,the comet rate, tail DNA content, tail length and tail extent moment was 6.21%, (30.14 ± 15.48)%, (16.93± 6.58)μm, 5.54 ± 4.22 at 16 weeks and 8.17%, (30.85 ± 15.76)%, (17,21±6.45)μm, 5.70 ± 4.17 at 21 weeks. Moreover, the levels were significantly higher than that in the control group(all P < 0.05). The tail DNA content and length of comet cell tail significantly increased in the combine group compared with T-2 group or DON group(P < 0.05). Conclusions Low dose T-2 toxin or DON can definitely result in DNA damage of mononuclear cells in peripheral blood of mice. The damage induced by T-2 toxin combined with DON is severer than that caused by T-2 toxin or DON alone. Key words: T-2 toxin; Deoxynivalenol; DNA damage; Mononuclear ceils in peripheral blood; Single cell gel electrophoresis