Comparative assessment of individual RONS in serum of smokers compared with non-smokers and their correlation with the lipid profile and antioxidant status

OBJECTIVE: Cigarette smoking generates free radicals, such as reactive oxygen and nitrogen species (RONS) that contribute to many diseases. The aim of this study was to compare the levels of individual RONS in serum from smokers and non-smokers, and to examine their impact on lipid profiles and the endogenous antioxidant status, which is represented by vitamins C and E. METHODS: Ninety-four healthy Egyptian volunteers (48 smokers and 46 non-smokers) were enrolled. Blood samples were collected and analysed for common haematological tests, lipid profiles, and serum antioxidants. Six reactive oxygen species and three reactive nitrogen species were measured. RESULTS: A significant increase in radical levels was observed, as well as significant increases in haemoglobin (Hb), haematocrit, platelet count, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol in smokers compared with non-smokers. In contrast, high-density lipoprotein cholesterol was significantly reduced in smokers compared with non-smokers. A moderate negative correlation was found between serum levels of vitamins C and E and O(2)(–•), HO(•), H(2)O(2), NO(•), and ONO(•), reflecting a negative impact of elevated RONS levels on the endogenous antioxidant status. CONCLUSION: These results may increase our understanding of the pathological role of smoking in several diseases.