J4

• 基础研究 • 上一篇    下一篇

低剂量X线照射诱导小鼠胸腺细胞凋亡适应性反应的相关凋亡基因p53、Bcl-2和Bax蛋白表达

吕 喆,刘 扬,王珍琦,马淑梅,刘光伟,孙延红,龚守良*   

  1. 吉林大学公共卫生学院卫生部放射生物学重点实验室,吉林 长春130021
  • 收稿日期:2004-03-23 修回日期:1900-01-01 出版日期:2004-11-28 发布日期:2004-11-28
  • 通讯作者: 龚守良

Expression of protein encoded by apoptosis-associated gene p53, Bcl-2,and Bax in adaptive response of thymocyte apoptosis in miceinduced by low dose radiation with X-rays

LU Zhe, LIU Yang, WANG Zhen-qi, MA Shu-mei, LIU Guang-wei, SUN Yan-hong, GONG Shou-liang*   

  1. MH Radiobiology Research Unit, School of Public Health, Jilin University, Changchun 130021, China
  • Received:2004-03-23 Revised:1900-01-01 Online:2004-11-28 Published:2004-11-28
  • Contact: GONG Shou-liang

摘要: 目的:探讨低剂量辐射诱导胸腺细胞凋亡适应性反应的相关基因蛋白调控机制。方法:用X射线全身照射Kunming系雄性小鼠,其诱导剂量(D1)为25、50、75、100和200 mGy(剂量率12.5 mGy•min-1),攻击剂量(D2)为1.5 Gy(剂量率287 mGy•min-1),D1和D2间隔6 h。通过流式细胞仪检测胸腺细胞凋亡相关基因p53、Bcl-2和Bax蛋白表达水平。 结果:D2组与假照射组比较,其胸腺细胞Bcl-2蛋白阳性百分率明显降低(P<0.05),Bax蛋白明显增加(P<0.05),而Bcl-2/Bax比值非常明显降低(P<0.001);p53蛋白非常明显增加(P<0.001)。D1+D2组与D2组比较,D1在25~75 mGy时,Bcl-2蛋白阳性百分率不同程度增加,Bax蛋白不同程度降低,而Bcl-2/Bax比值非常明显增高(P<0.01);p53蛋白明显降低(P<0.001或P<0.05)。 结论:在25~75 mGy低剂量辐射诱导小鼠胸腺细胞凋亡的适应性反应中,其相关凋亡基因蛋白Bcl-2表达增加,Bax降低,Bcl-2/Bax比值增高,p53降低,导致凋亡的胸腺细胞减少。

关键词: 电离, 辐射剂量, 细胞凋亡, 凋亡基因, 抗凋亡基因

Abstract: Objective To explore the regulative mechanism of apoptosis-associated gene proteins on the adaptive response of thymocyte apoptosis in mice induced by low dose radiation with X-rays. Methods Kunming male mice were irradiated with the inductive doses (D1: 25, 50, 75, 100 and 200 mGy; dose rate: 12.5 mGy•min-1) and the challenging dose (D2: 1.5 Gy; dose rate: 287 mGy•min-1). The time interval between D1 and D2 was 6 h. The expressive levels of thymocyte apoptosis-associated gene proteins were measured with flow cytometry. Results As compared with the sham-irradiation, the positive percentage of thymocyte Bcl-2 protein expression decreased significantly in D2 group (P<0.05), Bax increased significantly (P<0.05), and Bcl-2/Bax decreased significantly (P<0.001); p53 increased significantly (P<0.001). As compared with D2 group, the positive percentage of thymocyte Bcl-2 protein expression increased in varying degree in D1+D2 group of 25~75 mGy D1, Bax decreased in varying degree, and Bcl-2/Bax increased significantly (P<0.01); p53 decreased significantly (P<0.001 or P<0.05). Conclusion The apoptotic thymocytes in the adaptive response of thymocyte apoptosis in mice induced by irradiation with 25~75 mGy decrease significantly due to the increase of apoptosis-associated gene Bcl-2 protein expression and Bcl-2/Bax, the decrease of Bax and p53 protein expressions.

Key words: ionizing, radiation effects, apoptosis, apoptotic gene, anti-apoptotic gene

中图分类号: 

  • R144.1