角质细胞生长因子对肠上皮细胞辐射损伤的防护作用

Protective effect of keratinocyte growth factor on intestinal epithelial cell line No. 6 after irradiation

目的 探讨角质细胞生长因子 (KGF)的辐射防护作用与机制 ,为应用KGF防护肠道辐射损伤提供实验依据。方法 应用正常及不同剂量γ射线损伤的肠上皮细胞 (IEC 6) ,通过在培养体系中加入不同剂量的KGF后检测细胞增殖活性的变化以及凋亡细胞百分率 ,作为KGF辐射防护效应和细胞辐射敏感性变化的指标。结果 正常培养的IEC 6细胞 ,KGF呈剂量依赖型促细胞增殖作用 ;10Gy照射后KGF促细胞增殖作用显著减弱。KGF预处理能显著降低IEC 6细胞辐射敏感性 ,其IP50 ( 50 %增殖抑制照射量 )从对照( 15.3± 0 .6)Gy降至 ( 12 .2± 0 .4 )Gy。结论 KGF具有促肠上皮细胞增殖作用 ,其辐射防护作用表现为降低细胞辐射敏感性 ,抑制辐射诱导的细胞凋亡可能是其作用机制之一。

Objective To study radioprotective effect and the mechanism of keratinocyte growth factor (KGF) on irradiation induced intestinal epithelial cell line No. 6 (IEC 6) in order to found a basis for KGF clinical application. Methods KGF was added to the culture medium of IEC 6 pre and post exposured to various doses of irradiation. Cell proliferation and percentage of apoptic cells were determined to indicate the radioprotective effect and cell radiation sensitivity of KGF. Results KGF exerted dose depended effect on the proliferation of normal cultured IEC 6 and the effect was significantly alleviated on that of the radiated IEC 6. The pre administration of KGF reduced the IEC 6 radiation sensitivity significantly and 50% inhibition dose of irradiation for cell proliferation (IP 50 ) was decreased from (15.3 ±0.6)Gy in non KGF treated group to (12.2±0.4)Gy in KGF treated group. Conclusion KGF possesses the effect of improving the proliferation of IEC 6 and its radioprotective effect might be due to the decrease of cell radiation sensitivity and the inhibition of the apoptosis of radiation reduced cells.