Department of Biophysics, Medical School of Dicle University, 21280 Diyarbakir, Turkey.
Biol Trace Elem Res. 2010 Dec;138(1-3):238-49. doi: 10.1007/s12011-010-8615-3. Epub 2010 Feb 23.
This study was aimed to investigate the effect of extremely low-frequency magnetic field (ELF-MF) on apoptosis and oxidative stress values in the brain of rat. Rats were exposed to 100 and 500 µT ELF-MF, which are the safety standards of public and occupational exposure for 2 h/day for 10 months. Brain tissues were immunohistochemically stained for the active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. In addition, the levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were measured in rat brain. Final score of apoptosis and MPO activity were not significantly different between the groups. CAT activity decreased in both exposure groups (p < 0.05), while TAC was found to be lower in ELF 500 group than those in ELF-100 and sham groups (p < 0.05). MDA, TOS, and OSI values were found to be higher in ELF-500 group than those in ELF-100 and sham groups (p < 0.05). In conclusion, apoptosis was not changed by long-term ELF-MF exposure, while both 100 and 500 µT ELF-MF exposure induced toxic effect in the rat brain by increasing oxidative stress and diminishing antioxidant defense system.
本研究旨在探讨极低频磁场（ELF-MF）对大鼠大脑细胞凋亡和氧化应激值的影响。将大鼠暴露于 100 和 500 μT 的 ELF-MF 中，每日 2 小时，持续 10 个月，这是公众和职业暴露的安全标准。通过半定量评分系统，对大脑组织进行活性（裂解）半胱天冬酶-3 的免疫组织化学染色，以测量细胞凋亡指数。此外，还测量了大鼠大脑中的过氧化氢酶（CAT）、丙二醛（MDA）、髓过氧化物酶（MPO）、总抗氧化能力（TAC）、总氧化状态（TOS）和氧化应激指数（OSI）的水平。凋亡和 MPO 活性的最终评分在各组之间无显著差异。两组暴露组的 CAT 活性均降低（p < 0.05），而 ELF 500 组的 TAC 低于 ELF-100 组和假手术组（p < 0.05）。ELF-500 组的 MDA、TOS 和 OSI 值均高于 ELF-100 组和假手术组（p < 0.05）。总之，长期暴露于 ELF-MF 不会引起细胞凋亡，但 100 和 500 μT 的 ELF-MF 暴露均通过增加氧化应激和削弱抗氧化防御系统对大鼠大脑产生毒性作用。
