DNA损伤与慢性阻塞性肺疾病的关系

目的探讨DNA损伤与慢性阻塞性肺疾病(COPD)的关系。方法取20例吸烟的COPD患者、20例健康吸烟者和15例健康无吸烟者的外周血并分离淋巴细胞,用Western blot测淋巴细胞热休克蛋白70(HSP70)水平,用彗星实验测淋巴细胞DNA损伤程度。结果(1)DNA损伤积分:COPD患者[(42·1±10·2)分]明显高于健康吸烟者[(17·4±9·3)分],健康吸烟者高于健康无吸烟者[(10·1±3·6)分](F=70·86,P<0·01)。(2)外周血淋巴细胞HSP70表达水平(吸光度值):健康吸烟者(44·8±15·3)较健康无吸烟者(56·1±18·9)低,COPD者(20·9±9·9)又较健康吸烟者低(F=26·60,P<0·05)。(3)直线相关分析显示,HSP70水平与DNA损伤积分呈明显的负相关(r=-0·73,P<0·01)。结论DNA损伤在COPD的发生及发展中可能起一定作用,而DNA损伤的程度可能与HSP70表达水平的差异有关。

DNA damage in lymphocytes from patients with chronic obstructive pulmonary disease

OBJECTIVE: To explore the relationship of DNA damage in lymphocytes with chronic obstructive pulmonary disease (COPD). METHODS: Levels of heat shock protein 70 (HSP70) in peripheral lymphocytes were measured by Western blot in 20 COPD patients with smoking, 20 healthy smoking control subjects and 15 healthy nonsmokers. DNA damage in the lymphocytes was detected by Comet Assay. RESULTS: DNA damage score was 42.1 +/- 10.2, 17.4 +/- 9.3 and 10.1 +/- 3.6 in COPD patients, healthy smoking control subjects and healthy nonsmokers, respectively; the score was higher in COPD patients than that in healthy smoking control subjects, and was higher in smokers than in nonsmokers (P < 0.01). The levels of HSP70 (absorbency value) were 20.9 +/- 9.9, 44.8 +/- 15.3 and 56.1 +/- 18.9, respectively, and the difference was significant among the three groups (P < 0.05). The level of HSP70 showed a strongly negative correlation with DNA damage scores (r = -0.73, P < 0.01). CONCLUSION: DNA damage may be involved in the pathogenesis of COPD. The difference of HSP70 level may be associated with the level of DNA damage.