Xu Qian, Tong Jian, Jin Zong-da, Lu Min-xia, Du Hou-bing, Cao Yi
School of Radiation Medicine and Public Health, Sowchow University, Suzhou 215123, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2009 Sep;27(9):520-4.
To investigate radiation protection and possible mechanisms of low intensity microwave on gamma-ray exposed mice.
96 healthy Kunming mice were randomly divided into the following four groups: normal control, microwave (120 microW/cm(2), 900 MHz), gamma-ray irradiation (5 Gy), combined exposure of microwave and gamma-ray (120 microW/cm(2) + 5 Gy). The microwave group and combined group were exposed to 120 microW/cm(2) microwave firstly, 1 h/d, for 14 days. Then the ionization and combined group were exposed to 5 Gy (60)Co gamma-ray irradiation on the 15th day. Animals were sacrificed on the third, 6th, 9th and 12th day after irradiation. The sternum and spleen paraffin section were produced, and the histological changes were observed. Apoptosis rate of mice splenic cells in each group was examined by flow cytometry, and serum concentration of antioxidant and lipid peroxide was detected at the same time.
Bone marrow was obviously injured either by radiation or microwave exposure, characterized by undergoing four-phase lesions, namely apoptosis-necrosis, void, regeneration and recovery phase. Compared with the gamma-ray group, the pathological changes in combined group were slighter and the recovery was quicker. The pathological injuries of spleen were similar to that of bone marrow. Injuries in the combined group were slighter than gamma-ray group. It showed that apoptosis rate of splenic cells in combined group was significantly lower on the 6th and 9th day after gamma-ray radiation (23.02% +/- 15.18%, 25.37% +/- 11.62% respectively) from FCM results. Assays of oxidative damages suggested that serum superoxide dismutase (SOD) level in combined group increased while lipid peroxide level decreased significantly (P < 0.05).
Low intensity microwave may exert protection effects on injuries induced by ionizing radiation. The underlying mechanisms might be related with suppression on the hematopoietic cells apoptosis induced by gamma-ray radiation, inhibition of oxidative damages, and thus enhanced reconstruction of the hematopoietic system.
探讨低强度微波对γ射线照射小鼠的辐射防护作用及其可能机制。
将96只健康昆明小鼠随机分为四组：正常对照组、微波组（120 μW/cm²，900 MHz）、γ射线照射组（5 Gy）、微波与γ射线联合照射组（120 μW/cm² + 5 Gy）。微波组和联合组先接受120 μW/cm²微波照射，1 h/d，共14天。然后在第15天，照射组和联合组接受5 Gy ⁶⁰Coγ射线照射。照射后第3、6、9和12天处死动物。制作胸骨和脾脏石蜡切片，观察组织学变化。采用流式细胞术检测各组小鼠脾细胞凋亡率，同时检测血清抗氧化剂和脂质过氧化物浓度。
辐射或微波照射均可导致骨髓明显损伤，表现为经历四个阶段的损伤，即凋亡 - 坏死、空虚、再生和恢复阶段。与γ射线组相比，联合组的病理变化较轻，恢复较快。脾脏的病理损伤与骨髓相似。联合组的损伤比γ射线组轻。流式细胞术结果显示，联合组在γ射线辐射后第6天和第9天脾细胞凋亡率显著降低（分别为23.02% ± 15.18%，25.37% ± 11.62%）。氧化损伤检测表明，联合组血清超氧化物歧化酶（SOD）水平升高，脂质过氧化物水平显著降低（P < 0.05）。
低强度微波可能对电离辐射诱导的损伤具有防护作用。其潜在机制可能与抑制γ射线辐射诱导的造血细胞凋亡、抑制氧化损伤以及增强造血系统的重建有关。
