艾烟中的可吸入颗粒物诱发体外微核的实验研究

Micronucleus in vitro induced by inhalable particulate matters in moxa smoke

目的:用体外微核实验检测艾烟中的可吸入颗粒物(moxa smoke condensation,MSC)是否引起染色体或有丝分裂器的损伤产生微核,进而判定艾烟致染色体损伤的遗传毒性。方法:通过四唑盐比色实验得出MSC对中国仓鼠卵巢(Chinese hamster ovary,CHO)细胞染毒24h的半数抑制率(half maximal inhibitory concentration concentration,IC50)为0.087mg/mL,将体外培养哺乳动物CHO细胞系,分为溶剂对照组(阴性对照组)、阳性对照组(环磷酰胺作为溶剂)、低、中、高剂量组。低、中、高剂量组设定在艾烟致CHO细胞半数死亡浓度(IC50)上下,分别为1/8、1/4、1/2,即低剂量组(1/8 IC50 MSC)、中剂量组(1/4 IC50 MSC)、高剂量组(1/2 IC50MSC),观察3个剂量组的MSC染毒CHO细胞后染色体或有丝分裂器损伤后产生的微核是否具有剂量效应关系。结果:高、中、低剂量组的MSC所诱发的微核形成率较溶剂对照组增加,并且具有剂量效应关系,实验重复3次,可重复且有统计学意义(均P<0.05)。结论:MSC在高浓度时具有致染色体损伤的毒性,低浓度时毒性消失,遗传毒性也呈浓度依赖,艾烟的量是关键;临床应当注意控制艾烟浓度,把握好艾烟的量,尤其是临床的艾烟浓度安全标准,需进一步研究。

Objective To investigate whether inhalable particulate matters can cause the damage of chromosome or mitotic apparatus to produce micronucleus,and to evaluate genetic toxicology of moxa smoke on chromosome.Methods By MTT method,the 24 h half maximal inhibitory concentration（IC50）of moxa smoke condensation（MSC）on Chinese hamster ovary（CHO）cells was 0.087 mg/mL.CHO cells,which were cultured in vitro,were divided into a solvent control group,apositive control group（cyclophosphamide as solvent）,a low concentration group,a moderate concentration group and a high concentration group.The low concentration group,moderate concentration group and high concentration group were set approximately 1/8,1/4,1/2 of IC50,respectively.Whether micronucleus had dose-effect response induced by the damage of chromosome or mitotic apparatus was observed after CHO cells were contaminated by MSC in the low concentration group,moderate concentration group and high concentration group.Results The rate of micronucleus induced by MSC in the low concentration group,moderate concentration group and high concentration group was higher than that in the solvent control group（all P〈0.05）,which presented dosage-effect response.The experiment was repeated 3 times,indicating it was repeatable with statistical significance.Conclusion High concentration of MSC shows toxicity to induce chromosome damage,which disappears at low concentration.The genetic toxicology is also dependent on concentration,and the concentration of moxa smoke is essential.In clinical treatment,it is noted to control the level of moxa smoke,while the clinical safety standard of moxa smoke concentration is in need of further study.