Zong Chunyan, Ji Yongxin, He Qina, Zhu Shunxing, Qin Fenju, Tong Jian, Cao Yi
School of Public Health, Medical College of Soochow University , Suzhou, Jiangsu.
Int J Radiat Biol. 2015 Mar;91(3):270-6. doi: 10.3109/09553002.2014.980465. Epub 2015 Jan 27.
To determine whether mice exposed to radiofrequency fields (RF) and then injected with a radiomimetic drug, bleomycin (BLM), exhibit adaptive response and provide some mechanistic evidence for such response.
Adult mice were exposed to 900 MHz RF at 120 μW/cm(2) power density for 4 hours/day for 7 days. Immediately after the last exposure, some mice were sacrificed while the others were injected with BLM 4 h later. In each animal: (i) The primary DNA damage and BLM-induced damage as well as its repair kinetics were determined in blood leukocytes; and (ii) the oxidative damage was determined from malondialdehyde (MDA) levels and the antioxidant status was assessed from superoxide dismutase (SOD) levels in plasma, liver and lung tissues.
There were no indications for increased DNA and oxidative damages in mice exposed to RF alone in contrast to those treated with BLM alone. Mice exposed to RF+ BLM showed significantly: (a) reduced BLM-induced DNA damage and that remained after each 30, 60, 90, 120 and 150 min repair time, and (b) decreased levels of MDA in plasma and liver, and increased SOD level in the lung.
The overall data suggested that RF exposure was capable of inducing adaptive response and mitigated BLM- induced DNA and oxidative damages by activating certain cellular processes.
确定暴露于射频场（RF）后再注射放射模拟药物博来霉素（BLM）的小鼠是否表现出适应性反应，并为这种反应提供一些机制证据。
成年小鼠暴露于功率密度为120 μW/cm²的900 MHz射频下，每天4小时，共7天。最后一次暴露后立即处死部分小鼠，其余小鼠在4小时后注射BLM。在每只动物中：（i）测定血液白细胞中的原发性DNA损伤、BLM诱导的损伤及其修复动力学；（ii）从丙二醛（MDA）水平测定氧化损伤，并从血浆、肝脏和肺组织中的超氧化物歧化酶（SOD）水平评估抗氧化状态。
与单独用BLM处理的小鼠相比，单独暴露于RF的小鼠没有DNA和氧化损伤增加的迹象。暴露于RF+BLM的小鼠显著表现为：（a）BLM诱导的DNA损伤减少，且在每次30、60、90、120和150分钟的修复时间后仍保持减少；（b）血浆和肝脏中的MDA水平降低，肺中的SOD水平升高。
总体数据表明，RF暴露能够诱导适应性反应，并通过激活某些细胞过程减轻BLM诱导 的DNA和氧化损伤。
