Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland.
Department of Physics, Institute of Applied Physics (INFAP), Universidad Nacional de San Luis-CONICET, San Luis, Argentina.
Int J Radiat Biol. 2022;98(10):1581-1591. doi: 10.1080/09553002.2022.2055803. Epub 2022 Apr 21.
We investigated the possible effects of 50 and 60 Hz magnetic fields (MFs) on reactive oxygen species (ROS) production, DNA damage, DNA damage repair rate, as well as gene expression related to oxidative stress and DNA damage signaling.
Human SH-SY5Y neuroblastoma cells were sham-exposed or exposed to 100 µT MFs for 24 h, then assayed or further treated with 100 µM menadione for 1 h before the assay. The levels of ROS and cytosolic superoxide anion (O) were assayed fluorometrically. DNA damage and gene expression were assayed by comet assay and RT-qPCR, respectively. To examine whether MFs affected DNA damage repair rate, cells were allowed to repair their DNA for 1 or 2 h after menadione treatment and then assayed for DNA damage.
There was suggestive evidence of a general low-magnitude increase in the expression of ROS-related genes (primarily genes with antioxidant activity) when quantified immediately after MF exposure, suggesting a response to a small increase in ROS level. The possible upregulation of ROS-related genes is supported by the finding that the level of menadione-induced ROS was consistently decreased by 50 Hz MFs (not significantly by 60 Hz MFs) in several measurements 30-60 min after MF exposure. MF exposures did not affect cytosolic O levels, DNA damage, or its repair rate. Changes in the expression of DNA damage-signaling genes in the MF-exposed cells did not exceed the expected rate of false-positive findings. No firm evidence was found for differential effects from 50 60 Hz MFs.
While only weak effects were found on the endpoints measured, the results are consistent with MF effects on ROS signaling.
我们研究了 50Hz 和 60Hz 磁场（MFs）对活性氧（ROS）产生、DNA 损伤、DNA 损伤修复率以及与氧化应激和 DNA 损伤信号相关的基因表达的可能影响。
人类 SH-SY5Y 神经母细胞瘤细胞接受假暴露或暴露于 100μT MFs 24 小时，然后在测定前用 100μM 甲萘醌处理 1 小时。通过荧光法测定 ROS 和胞浆超氧阴离子（O）的水平。通过彗星试验和 RT-qPCR 分别测定 DNA 损伤和基因表达。为了研究 MFs 是否影响 DNA 损伤修复率，在用甲萘醌处理后允许细胞修复其 DNA 1 或 2 小时，然后测定 DNA 损伤。
MF 暴露后立即定量，发现与 ROS 相关的基因（主要是具有抗氧化活性的基因）的表达有暗示性的低幅度增加，表明对 ROS 水平略有增加的反应。MF 暴露后 30-60 分钟，MF 暴露可一致降低（60Hz MF 无显著降低）几种测量中甲萘醌诱导的 ROS 水平，这支持了 ROS 相关基因可能上调的观点。MF 暴露不会影响胞浆 O 水平、DNA 损伤或其修复率。MF 暴露细胞中 DNA 损伤信号基因的表达变化未超过假阳性发现的预期率。没有确凿的证据表明 50Hz 和 60Hz MFs 的作用存在差异。
尽管在测量的终点上只发现了微弱的影响，但结果与 MF 对 ROS 信号的影响一致。
