Acute and chronic impact of smoking on salivary and serum total antioxidant capacity.

OBJECTIVE: To investigate increased oxidative stress in saliva of smokers along with their serum. METHODS: The case-control study was conducted from September to December 2008 in the Department of Biochemistry of the Medical School, Kirikkale University, Kirikkale, Turkey. A blood sample and saliva samples before and after smoking were collected from the smokers, while blood and saliva samples were taken from the controls. All samples were taken concurrently. The samples were measured for total antioxidant capacity, total oxidant stress, oxidative stress index, malondialdehyde, nitric oxide and total sulfhydryl groups. Levels of superoxide dismutase and glutathione peroxidase were also measured on saliva samples. SPSS 13 was used for statistical analysis. RESULTS: Of the 54 subjects in the study, 27(50%) were smokers with a mean age of 28.4 ± 5.42 years, and 27 (50%) were controls with a mean age of 29.7 ± 8.03 years. Total oxidant stress, oxidative stress index, malondialdehyde and nitric oxide levels were found higher in the serum samples of smokers (p < 0.05), and the levels of total sulfhydryl groups in smokers were lower compared with the controls (p < 0.05). Among the smokers, salivary malondialdehyde levels were higher before and after smoking (p < 0.05), glutathione peroxidase levels were lower than the controls, and salivary nitric oxide levels after smoking were higher than both those of the control group and the levels before smoking (p < 0.05). CONCLUSION: Both acute and chronic increased oxidative conditions may be a significant sign of the destructive effects of smoking. The investigation of disorders in smokers concerning oxidative stress will be beneficial in terms of novel approaches and treatment modalities.