Effects of Active and Passive Smoking on Antioxidant Enzymes and Antioxidant Micronutrients

ABSTRACT

In the present study, we analyzed the relationship between cigarette smoke exposure and several markers of oxidative status, plasma thiobarbituric acid reactive substances, erythrocyte glutathione peroxidase, superoxide dismutase and catalase in a group of students. Of the 105 men enrolled into the study, 35 had never smoked and not exposed to cigarette smoke at all. Thirty five had smoked at least 15 cigarettes per day for at least five years (active smokers) and 35 had been exposed to cigarette smoke at indoor environment at least 2 cigarette/day on ≥5d/wk for > 6 months (passive smokers). The urine cotinine level was used as a smoking marker. Erythrocyte SOD activity and plasma TBARs were significantly higher in active and passive smokers than in non-smokers (p < 0.05). However, erythrocyte GSH-Px and CAT were significanly lower in active smokers than in non smokers (p < 0.05). Serum vitamin C and E levels were significantly lower in active and passive smokers than in nonsmokers (p < 0.05). For active and passive smokers, there were significant possitive correlations between urine cotinine levels and plasma TBARs levels (r = 0.60, p < 0.01, r = 0.43, p < 0.05) and a negative correlation between urine cotinine levels and plasma vitamin C (r = -0.48, p < 0.05, r = -0.59, p < 0.01). In conclusion, during both passive and active smoking, oxidative stress was clearly exacerbated and the dynamic balance between oxidation and antioxidation was seriously disrupted, which was closely related to many disorders or diseases in active and passive smokers.