Applications of Phospho-histone H2AX Enzyme-Linked Immunosorbent Assay in Vitro Genotoxicity Evaluation of Cigarette Smoke / 分析化学

ABSTRACT

Phospho-histone H2AX(γH2AX) has been widely used in vitro genotoxicity evaluation of ionizing radiation, carcinogenic substances and cigarette smoke as an important biomarker of DNA double stranded breaks ( DSBs) . The study developed an enzyme-linked immunesorbent assay for detection of the content ofγH2AX in cells to evaluate the genotoxicity of cigarette smoke. The study exposed CHO cells with cigarette smoke total particulate matter ( TPM) and cigarette smoke condensate ( CSC) of different dose, dose-effect relationship between smoke exposure and DNA damage and the poisonous difference of cigarette smoke components has been investigated by detecting the content change ofγH2 AX in cells under different exposure time and dose. In addition, reactive oxygen species ( ROS) in cells were also detected to study the mechanism of cigarette smoke exposure induced DSBs. The experiment result showed that the required time for the level ofγH2AX in cells grew to the peak prolonged with increased exposure dose. Once the level of γH2AX in cells grew to the peak value, then it decreased slowly; the level of γH2AX in cells rised with increasing dose of cigarette smoke;The effect of TPM on the content change of γH2AX was more than CSC; Moreover, smoke exposure could induce concentration increase of ROS in cells, and a good correlation of content change of ROS and γH2AX in cells were found, free radicals in cigarette smoke may be one major cause of DSBs.