ABSTRACT

This study evaluates the DNA damage induced by pulsed magnetic field (MF) on S. cerevisiae cells exposed during chronological aging. Samples were exposed to 25 Hz pulsed MF (1.5mT, 8 h/day) while cells were aging chronologically. Clonogenic drop test was used to study cellular survival and the mutation frequency was evaluated by scoring the spontaneous revertant mutants. DNA damage analysis was performed after aging by electrophoresis and image analysis. Yeast cells aged during 40 days of exposure showing that pulsed MF exposure induced a premature aging. In addition, a gradual increase in spontaneous mutants was found in pulsed MF samples in relation to unexposed controls. An increase in DNA degradation, over the background level in relation to controls, was observed at the end of the exposure period. In conclusion, exposure of S. cerevisiae cells to pulsed MF during chronological aging could induce genomic DNA damage.

摘要

本研究评估脉冲磁场 (MF) 对酿酒酵母引起的 DNA 损伤在时间老化过程中暴露的细胞。当细胞按时间顺序老化时，将样品暴露于 25 Hz 脉冲 MF（1.5mT，8 小时/天）。克隆形成下降试验用于研究细胞存活，并通过对自发回复突变体评分来评估突变频率。老化后通过电泳和图像分析进行DNA损伤分析。酵母细胞在暴露 40 天期间老化，表明脉冲 MF 暴露会导致过早老化。此外，与未暴露的对照相比，在脉冲 MF 样本中发现自发突变体逐渐增加。在暴露期结束时观察到 DNA 降解的增加，超过了与对照相关的背景水平。总之，酿酒酵母的暴露细胞在按时间顺序老化期间脉冲 MF 可诱导基因组 DNA 损伤。