Analysis of chromosome aberration due to ethidium bromide using AFM / 中国病理生理杂志

ABSTRACT

AIM:To study chromosome aberration due to ethidium bromide (EB), a heterocyclic organic compound and an organic fluorescence dye commonly used in biochemical experiment, and to help further understanding the molecular mechanism of tumor or cancer induced by EB and other heterocyclic organic compounds. METHODS: The toxicity action of EB was evaluated from three aspects including DNA, chromosome and embryo stem cells (ESCs) using atomic force microscopy (AFM), and thereinto, the morphology structural difference of ESCs treated with two EB doses was also valuated. RESULTS: The morphological structures of DNA, chromosome and ESCs were dramatically damaged. The average height of DNA decreased 0.5 nm; chromosomal arms were ruptured from centromere location; molecules of cellular membrane congregated and loop-like structure formed, and ES cell masses were collapsed and became dead after large EB doses treatment and mesh-like morphological structure was discernable. CONCLUSION: The toxicity action of EB is strong and destroys the surface structure of DNA and chromosome. EB induces structural aberration of ES cellular membrane and cell death. The results indicate that the action of EB is externalized at gene level and cell level, which is important to study the carcinogenicity of EB.