Tobacco Smoking in Relation to the Phenotype of Alpha-1-Antitrypsin and Serum Vitamin C Concentration

Purpose: To investigate the effects of tobacco smoking on serum alpha-1-antitrypsin (AT) concentrations in relation to the Pi types of AT (MM and non-MM phenotypes) and vitamin C concentrations in the serum of Thai smokers and non-smokers. Design: Cross-sectional study of smokers and non-smokers in a military unit in Bangkok, Thailand. Materials and Methods: 123 male smokers and 66 male non-smokers were randomly selected from a military unit in Bangkok. Venous blood was analysed by rocket immunoelectrophoresis for AT concentrations. AT phenotype and vitamin C status were determined by iso-electrofocusing (IEF) and spectro-photometric methods. Co-variance analysis was used to determine whether smoking directly influences AT levels. Results: There were statistically significantly higher levels of serum AT and thiocyanate concentrations in smokers than in non-smokers. The thiocyanate level correlated with the duration and quantity of cigarette smoking. However, vitamin C, an antioxidant, was found with statistically significantly lower concentrations in smokers compared with non-smokers. Conclusions: The results of this study suggest that the increase of AT concentrations in smokers is an immediate response of the organism to limit the damaging effects of smoking on lung tissue, while the decrease of the antioxidant vitamin C relates to the long-term risk of smokers developing cancer.