低强度2450 MHz微波阻断兔晶状体上皮细胞周期及对相关基因表达的影响

目的　探讨不同剂量微波辐射对兔晶状体上皮细胞 (RLEC)细胞周期的阻断作用 ,以及微波辐射对细胞周期调控基因P2 1WAF1、P2 7Kip1及c myc表达的影响。 方法　应用频率为 2 4 5 0MHz、功率密度分别为 0 10 (A组 )、0 2 5 (B组 )、0 5 0 (C组 )、1 0 0 (D组 )及 2 0 0mW /cm2 (E组 )的微波连续辐射体外培养的RLEC 8h ,光镜下观察辐射前、后细胞形态学的改变 ,采用流式细胞技术测定细胞周期 ,Western印迹法检测功率密度 2 0 0mW /cm2 的微波辐射 4、6及 8h对P2 1WAF1、P2 7Kip1及c myc基因表达的影响。以无微波辐射对照者为F组 ,进行对照研究。结果　微波辐射 8h后 ,C、D及E组RLEC肿胀和聚集 ,甚至出现细胞固缩和脱壁现象 ,G0 /G1期细胞所占比例明显升高 (P <0 0 5 )。功率密度 2 0 0mW /cm2 的微波辐射 4h ,P2 7Kip1表达水平即开始明显升高 ,而c myc表达水平开始逐渐下降 ,P2 1WAF1表达无变化。结论　功率密度≥ 0 5 0mW/cm2 的微波可阻断RLEC细胞周期 ,并使细胞停滞于G0 /G1期 ;这种阻断作用可能是通过调节调控细胞周期转换的基因P2 7Kip1和c myc而实现。

Low-intensity microwave blockes cell cycle and regulate cell cycle related gene expression in rabbit lens epithelial cells

Objective To study the cell cycle arrest induced by different doses of microwave in cultured rabbit lens epithelial cells (RLECs) and its effects on the related gene expression of P21 WAF1, P27 Kip1 and c-myc . Methods Cultured rabbit lens epithelial cells were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.10 mW/cm2 (A group), 0.25 mW/cm2 (B group), 0.50 mW/cm2 (C group), 1.00 mW/cm2 (D group) and 2.00 mW/cm2 (E group) for 8 hours. The morphological change of RLECs was observed under microscope, effects of microwave radiation on RLECs cell cycle were measured by flow cytometry. Expression of P21 WAF1, P27 Kip1 and c-myc were evaluated by western blot after 2.00 mW/cm2 microwave radiation for 4 hours, 6 hours and 8 hours respectively. All the results were compared with F group, which was as controls without microwave radiation.Results 8 hours after radiation, RLECs of C, D and E groups showed RLECs cell swelling, congregation and detachment, the percentage of cells in G 0/G 1 phase obviously was increased (P<0.01). No obvious change could be detected in 0.10 mW/cm2 and 0.25 mW/cm2 microwave groups. The gene expression of P27 Kip1 was increased and c-myc was decreased after 2.00 mW/cm2 radiation, it did not affect the gene expression of P21 WAF1 .Conclusion Microwave exceeding 0.50 mW/cm2 can block RLECs cell cycle at G 0/G 1 phase, which may be related to regulation of P27 Kip1 and c-myc expression, but not P21 WAF1.