比较细胞松弛素A与B在胞质分裂阻断法微核试验中的应用

Comparison of cytochalasin A and B in the cytokinesis-blocking micronucleus assay

目的比较细胞松弛素A(Cyto A)及细胞松弛素B(Cyto B)对微核试验常用细胞系——中国仓鼠肺成纤维细胞(CHL)毒性及对体外微核试验结果的影响。方法在荧光显微镜下观察由微丝组成的应力纤维结构,并使用CHL开展胞质分裂阻断法微核试验,比较两者对多核细胞率及含微核双核细胞率的影响。结果不同浓度的Cyto A和Cyto B与细胞作用24 h后,与对照组(26%±7%)比较均可诱导多核细胞形成率的显著升高(Cyto A及Cyto B 3.0μg/ml浓度组分别为58%±12%和72%±9%,P <0.001),且Cyto A在3.0μg/ml浓度条件下诱导的平均多核细胞率与1.5μg/ml浓度组比较有所降低。Cyto A处理组在MMC浓度分别为0、0.1和0.3μg/ml时的微核率分别为0.25%±0.16%、 1.98%±0.59%和3.80%±0.90%;而Cyto B处理组在相同MMC浓度时的微核率分别为0.32%±0.16%、2.50%±0.61%和5.05%±1.09%。结论虽然Cyto B的多核细胞造模效果略优于Cyto A,两者均可有效用于胞质分裂阻断法微核研究。研究结果将为相关领域研究者提供可借鉴的实际经验。

Objective To compare the cytotoxicity and the effects of cytochalasin A (Cyto A) and cytochalasin B (Cyto B) on the results of in vitro micronucleus test on Chinese hamster lung (CHL) cells frequently used in micronucleus test. Methods The stress fiber structures formed by actin microfilaments were observed under fluorescence microscope, and the cytokinesis-blocking micronucleus test was performed to compare the multinuclear cell rate and micronucleus rate induced by Cyto A and Cyto B. Results The cells were treated with different concentrations of Cyto A and Cyto B for 24 hours, and both treatment could significantly increase the multinuclear cell rate. For Cyto A and Cyto B treatment at 3.0 μg/ml, the multinuclear cell rate was 58%± 12% and 72%± 9%, respectively, compared with the control of 26%± 7%(P < 0.001). The multinuclear cell rate induced by Cyto A at 3.0 μg/ml was lower than that at 1.5 μg/ml. The micronucleus ratio of cells in Cyto A treatment group along with different concentration of MMC (0, 0.1 and 0.3 μg/ml) were 0.25%± 0.16%, 1.98%± 0.59% and 3.80%± 0.90%, respectively;while the micronucleus ratio under similar conditions after Cyto B treatment was 0.32%± 0.16%, 2.50%± 0.61% and 5.05%± 1.09%, respectively. Conclusion Although Cyto B showed slight better effects on establishing the multinucleated cell model, both Cyto A and Cyto B could be effectively used in the cytokinesis-blocking micronucleus test.