用TK基因突变试验评价土荆芥精油的遗传毒性

Evaluation of the genetic toxicity of essential oil from Chenopodium ambrosioides L.with TK mutation assay

目的:采用TK基因突变试验评价土荆芥精油的遗传毒性,为其安全性评价提供资料。方法:土荆芥精油浓度设置分别为体积分数0.002%、0.004%、0.006%和0.008%,对L5178Y细胞进行3 h染毒处理;同时分别设二甲基亚砜(DMSO)和环磷酰胺(CP)为溶剂对照和阳性对照,微孔板法进行TK基因突变试验。检测土荆芥精油对L5178Y细胞的细胞毒性及TK基因位点突变频率。结果:随土荆芥精油浓度的增大,L5178Y细胞相对存活率(RS)、相对悬浮生长率(RSG)和相对总生长率(RTG)较溶剂对照组有下降趋势;0.008%剂量组时,RS、RSG和RTG分别为溶剂对照组的29.38%、38.13%和5.75%,表现出明显的细胞毒性;与溶剂对照组相比,突变频率(TMF)随土荆芥精油浓度增加则呈上升趋势(F=410.5,P=0.00)。TMF在土荆芥精油各浓度组间以及和阳性、溶剂对照组间的多重比较差异均有统计学意义(P<0.05)。小集落百分比(SC)均超过95%。结论:土荆芥精油具有一定的细胞毒性,可诱导L5178Y细胞TK基因位点突变频率增高,有一定的致突变性。

OBJECTIVE：The genotoxicity of essential oil fromChenopodium ambrosioides L. was evaluated withTK gene mutation test to provide information for its safety. METHODS：The mouse lymphoma cells L5178Y were exposed to essential oil ofC. ambrosioides at volume fraction concentrations of 0.002%, 0.004%,0.006% and 0.008% for 3 h. 1% dimethyl sulfoxide （DMSO） and 10μg/mL cyclophosphamide （CP） were used as solvent and positive controls,respectively.TK gene mutation was assessed with microwell method to detect cytotoxicity and mutation frequency atTK locus in L5178Y cells.RESULTS：Relative survival （RS）,relative suspension growth （RSG） and relative total growth （RTG） decreased when concentration of essential oil fromC. ambrosioides increased,with only 29.38%,38.13% and 5.75%,respectively,in 0.008% dose group indicating significant cytotoxicity. Compared with the solvent control mutation frequency （TMF） increased with the rising concentration of essential oil（F=410.5,P=0.00）. Multiple comparisons of TMT between the different essential oil groups,positive control group and solvent control group were statistically significant differences （P〈0.05）. The percentage of small growth mutant （SCM） was more than 95%. CONCLUSION： Essential oil fromC. ambrosioides showed strong cytotoxicity and could increase mutation frequency at TK gene locus in L5178Y cells.