Koul Ashwani, Singh Mona, Gangar Subhash Chander
Department of Biophysics, Basic Medical Sciences Block, Panjab University, Chandigarh 160 014, India.
Indian J Exp Biol. 2005 Dec;43(12):1139-43.
Cigarette smoke (CS) has been established as one of the major risk factors for many pathologies including lung cancer in humans and experimental animals. In view of the discrepancy about the role of alpha-tocopherol (AT) in carcinogenesis, the present study was designed to investigate the effects of different doses of AT on benzo(a)pyrene-DNA [B(a)P-DNA] adduct formation in lungs of CS inhaling mice. Extent of carcinogen-DNA adduct formation has been considered as an index for carcinogenesis. Feeding of 35 IU AT/kg body weight increased B(a)P-DNA adducts formation significantly whereas feeding of 5 IU AT/kg body weight did not altered much the B(a)P-DNA adduct levels when both were compared to the control counterparts. With CS inhalation, the B(a)P-DNA adducts formation increased in all the groups when compared to their respective sham counterparts. Interestingly, in CS exposed groups, there was least increase in B(a)P-DNA adducts formation in 5 IU AT/kg fed animals followed by the control and 35 IU AT/kg body weight fed groups respectively. The results suggest that higher doses of AT accentuate DNA adduct formation in CS inhaling mice.
香烟烟雾（CS）已被确认为人类和实验动物中包括肺癌在内的多种病理状况的主要危险因素之一。鉴于α-生育酚（AT）在致癌作用中的作用存在差异，本研究旨在探讨不同剂量的AT对吸入CS的小鼠肺部苯并（a）芘-DNA [B（a）P-DNA]加合物形成的影响。致癌物-DNA加合物的形成程度被视为致癌作用的一个指标。与对照小鼠相比，以35 IU AT/千克体重喂食可显著增加B（a）P-DNA加合物的形成，而以5 IU AT/千克体重喂食对B（a）P-DNA加合物水平的改变不大。吸入CS后，与各自的假手术组相比，所有组的B（a）P-DNA加合物形成均增加。有趣的是，在CS暴露组中，以5 IU AT/千克体重喂食的动物中B（a）P-DNA加合物形成的增加最少，其次分别是对照组和以35 IU AT/千克体重喂食的组。结果表明，较高剂量的AT会加剧吸入CS的小鼠中的DNA加合物形成。
