Amara Salem, Douki Thery, Ravanat Jean-Luc, Garrel Catherine, Guiraud Pascale, Favier Alain, Sakly Mohsen, Ben Rhouma Khémais, Abdelmelek Hafedh
Laboratoire de Physiologie Animale, Faculté des Sciences de Bizerte, 7021 Jarzouna, Tunisia.
Phys Med Biol. 2007 Feb 21;52(4):889-98. doi: 10.1088/0031-9155/52/4/002. Epub 2007 Jan 22.
The aim of this study was to investigate the effect of static magnetic field (SMF) exposure in antioxidant enzyme activity, the labile zinc fraction and DNA damage in THP1 cells (monocyte line). Cell culture flasks were exposed to SMF (250 mT) during 1 h (group 1), 2 h (group 2) and 3 h (group 3). Our results showed that cell viability was slightly lower in SMF-exposed groups compared to a sham exposed group. However, SMF exposure failed to alter malondialdehyde (MDA) concentration (+6%, p>0.05) and glutathione peroxidase (GPx) (-5%, p>0.05), catalase (CAT) (-6%, p>0.05) and superoxide dismutase (SOD) activities (+38%, p>0.05) in group 3 compared to the sham exposed group. DNA analysis by single cell gel electrophoresis (comet assay) revealed that SMF exposure did not exert any DNA damage in groups 1 and 2. However, it induced a low level of DNA single strand breaks in cells of group 3. To further explore the oxidative DNA damage, cellular DNA for group 3 was isolated, hydrolyzed and analysed by HPLC-EC. The level of 8-oxodGuo in this group remained unchanged compared to the sham exposed group (+6.5%, p>0.05). Cells stained with zinc-specific fluorescent probes zinpyr-1 showed a decrease of labile zinc fraction in all groups exposed to SMF. Our data showed that SMF exposure (250 mT, during 3 h) did not cause oxidative stress and DNA damage in THP1 cells. However, SMF could alter the intracellular labile zinc fraction.
本研究的目的是调查静磁场（SMF）暴露对THP1细胞（单核细胞系）抗氧化酶活性、不稳定锌组分和DNA损伤的影响。将细胞培养瓶暴露于SMF（250 mT）下1小时（第1组）、2小时（第2组）和3小时（第3组）。我们的结果表明，与假暴露组相比，SMF暴露组的细胞活力略低。然而，与假暴露组相比，第3组中SMF暴露未能改变丙二醛（MDA）浓度（+6%，p>0.05）以及谷胱甘肽过氧化物酶（GPx）（-5%，p>0.05）、过氧化氢酶（CAT）（-6%，p>0.05）和超氧化物歧化酶（SOD）活性（+38%，p>0.05）。通过单细胞凝胶电泳（彗星试验）进行的DNA分析显示，第1组和第2组中SMF暴露未造成任何DNA损伤。然而，它在第3组细胞中诱导了低水平的DNA单链断裂。为了进一步探索氧化性DNA损伤，分离、水解并通过高效液相色谱-电化学检测法（HPLC-EC）分析了第3组的细胞DNA。与假暴露组相比，该组中8-氧代鸟嘌呤（8-oxodGuo）水平保持不变（+6.5%，p>0.05）。用锌特异性荧光探针zinpyr-1染色的细胞显示，所有暴露于SMF的组中不稳定锌组分均减少。我们的数据表明，SMF暴露（250 mT，持续3小时）不会在THP1细胞中引起氧化应激和DNA损伤。然而，SMF可改变细胞内不稳定锌组分。
