脱氧雪腐镰刀菌烯醇与黄曲霉毒素B_1单一及联合染毒对小鼠肠道菌群的影响

Effects of Single and Combined Exposure of Deoxynivalenol and Aflatoxin B1on Intestinal Microflora in Mice

本试验旨在研究脱氧雪腐镰刀菌烯醇(DON)与黄曲霉毒素B1(AFB_1)单一及联合染毒对小鼠肠道菌群多样性、物种丰度的影响。选用18日龄昆明系雄性小鼠96只,随机分成4组,每组24只。其中,对照组灌服生理盐水,DON组灌服500μg/kg DON,AFB_1组灌服200μg/kg AFB_1,DON+AFB_1组灌服200μg/kg AFB_1+500μg/kg DON,连续灌服45 d。分别在试验第0天(试验开始前)、第45天时,无菌条件下采取直肠内新鲜粪便,每组随机采取3份,用Illumina HiSeq高通量测序技术分析肠道菌群结构和组成的变化。结果显示:与对照组相比,DON组、AFB_1组以及DON+AFB_1组拟杆菌门和拟杆菌纲的丰度均极显著低于对照组(P<0.01)。与DON组和AFB_1组相比,DON+AFB_1组拟杆菌纲的丰度极显著降低(P<0.01)。DON组、AFB_1组以及DON+AFB_1组脱铁杆菌门的丰度与对照组相比均极显著降低(P<0.01)。DON组、AFB_1组以及DON+AFB_1组梭菌纲的丰度极显著高于对照组(P<0.01)。DON组和DON+AFB_1组螺旋体门的丰度与对照组相比极显著升高(P<0.01)。综上所述,DON与AFB_1单一及联合染毒均可改变肠道内菌群的丰度,降低有益菌丰度,升高有害菌丰度,并且DON和AFB_1表现出明显的互作性,具有协同效应。

The present experiment was conducted to evaluate the effects of single and combined exposure of deoxynivalenol(DON) and aflatoxin B1(AFB1) on intestinal microflora diversity and species abundance in mice.Ninety-six Kunming mice(male,18-day-old) were randomly divided into 4 groups with 24 mice in each group.Mice in control group were fed physiological saline by gavage.Mice in DON group were fed 500 μg/kg DON by gavage.Mice in AFB1 group were fed 200 μg/kg AFB1 by gavage.Mice in DON+AFB1 group were fed 500 μg/kg DON+200 μg/kg AFB1 by gavage.The trial was conducted for 45 d.On the days 0(before the experiment) and 45 of the experiment,the fresh dejections in the rectum from each group(each group was randomly taken 3 samples) were randomly taken under aseptic conditions,and then the changes of the structure and composition of the microbial community were analyzed using Illumina HiSeq high-throughput sequencing technology.The results showed that compared with the control group,the abundances of Bacteroidetes and Bacteroidia in DON,AFB1 and DON+AFB1 groups was significantly reduced(P<0.01),and the abundance of Bacteroidia in DON+AFB1 group was significantly lower than that in DON and AFB1 groups(P<0.01).Compared with the control group,the abundance of Deferribacteres in DON,AFB1 and DON +AFB1 groups was significantly reduced(P<0.01),while the abundance of Clostridia in DON,AFB1 and DON + AFB1 groups was significantly increased(P<0.01).Moreover,the abundance of Spirochaetes in DON and DON+AFB1 groups was significantly higher than that in control group(P<0.01).In conclusion,single and combined exposure of DON and AFB1 all can alter the abundances of intestinal microflora,decrease the abundances of beneficial bacteria,and increase the abundances of harmful bacteria.DON and AFB1 exhibit a significant interaction with synergistic effects.