摘要
【目的】(1)研究黄曲霉毒素B1(AFB1)不同染毒水平(3,30,300μg·kg-1BW)染毒后,在不同时间点导致雏鸭肝细胞DNA损伤情况;(2)探明AFB1染毒剂量及染毒时间与雏鸭肝细胞DNA损伤之间的关系,为AFB1遗传毒性提供研究模型。【方法】96只雄性北京鸭雏鸭,随机分为16组,每组6只。第1组为对照组,第2至6组为低剂量(染毒)组、第7至11组为中剂量(染毒)组、第12至16组为高剂量(染毒)组。对照组、低剂量组、中剂量组、高剂量组雏鸭分别灌胃25%DMSO水溶液,0.25,2.5,25μg·mL-1溶液各1mL,对照组于灌胃1h后,各剂量染毒组分别于灌胃染毒1、2、8、24、48h用彗星试验检测肝细胞DNA损伤。【结果】试验表明,雏鸭对于AFB1导致的肝细胞DNA损伤非常敏感,肝细胞DNA损伤程度与AFB1摄入量以及摄入时间有关。经口染毒2h左右DNA损伤达到高峰,所有染毒组在尾长、尾部DNA百分含量、尾矩、Olive尾矩等指标上均显著高于对照组(P<0.05);随着AFB1染毒剂量增加,DNA损伤程度加深、持续时间延长。【结论】(1)AFB1致雏鸭肝细胞DNA损伤的效应非常强,低剂量(3μg·kg-1BW)AFB1暴露就能够引起雏鸭肝细胞DNA发生显著损伤。(2)经口染毒AFB12h后雏鸭肝细胞DNA损伤达到高峰,此时DNA损伤程度与AFB1暴露之间的量效关系最为明显。(3)雏鸭是研究AFB1遗传毒性的一个良好动物模型,彗星试验能够反映AFB1致雏鸭肝细胞DNA损伤的量效关系。
[Objective] Aflatoxin B1（AFB1） is one of the most potent naturally occurring carcinogens and classified as a group I carcinogen. This study has two objectives： （1） To evaluate the effect of 3, 30, 300 gg-kg^-1 BW on DNA damage in hepatic cells in Beijing ducklings at different times after administrated by oral feeding. （2） To study the relationship between the level of DNA damage and concentration of AFB1, time after exposed to AFB1 to provide research model for genotoxicity of AFB1. [Method] Ninety-six male Beijing ducklings were randomly divided into 16 groups with 6 ducklings in each one. Each duckling in group 1 was administered orally with 1mL 25% DMSO solution as control, and low （group 2 to 6）, moderate （group 7 to 11）, high （group 12 to 16） AFB1 exposure groups were given 1 mL with 0.25, 2.5, 25μg.mL^-1 25% DMSO solution by gavage, respectively. The modified comet assay was performed at 1 h in control group, and at 1, 2, 8, 24, 48 h in AFB1 exposure groups on hepatic cells after AFB1 administration. [Result] The results showed that ducklings were sensitive to hepatic DNA damage induced by AFB1, and the level of DNA damage was associated with concentration and time after AFB1 intake. DNA strand breaks reached peak value at 2 h of exposure, and all different doses of AFB1 could induce significantly higher tail length, tail DNA%, tail moment, Olive tail moment than in control group （P〈0.05）. With AFB1 concentration increasing, the duration of DNA damage prolonged, and under the condition of the same treatment time, the DNA damage was more serious. [ Conclusion ] From the results, three conclusions were drawn as follows： （1） Ducklings are sensitive to DNA damage in live cells induced by AFB1, and low level （3μg-kg^-1 BW） exposure of AFB1 can induce significantly hepatic DNA damage in ducklings. （2） The level of DNA damage reached the peak at 2 h after a single oral administration of AFB1, and at this time the dose-effect relationship was obvious in this experiment. （3） Duckling is an ideal animal model for study of AFB1 genotoxicity, and comet assay is an useful tool for monitoring the hepatic DNA damage induced by AFB1 in ducklings.
出处
《中国农业科学》
CAS
CSCD
北大核心
2010年第4期821-827,共7页
Scientia Agricultura Sinica
基金
国家"十一五"科技支撑计划重点项目(2006BAD12B03)
