Effects of cigarette smoke, nicotine and cotinine on red blood cell hemolysis and their -SH capacity.

BACKGROUND Smoking is a leading cause of premature death. Red blood cell (RBC) membrane lipids are rich in polyunsaturated fatty acids; therefore, the effect of oxygen on RBC membranes is more prominent than on other body tissues. The attachment of peroxidants to RBC membranes can result in hemolysis. OBJECTIVES The present study was conducted to assess the sensitivity of RBCs to 2,2'-azo-bis-(2-amidinopropane) dihydrochloride in smokers and nonsmokers. The effect of cigarette smoke, nicotine (1 mug/mL, 1.5 mug/mL and 2.5 mug/mL) and cotinine (1.25 mug/mL, 2.5 mug/mL and 5 mug/mL) on RBC hemolysis was also examined. RESULTS RBC hemolysis in smokers was 21.6% higher than in non-smokers (P<0.05). Cigarette smoke increased 2,2'-azo-bis-(2-amidino-propane) dihydrochloride-induced RBC hemolysis by 281.7%. Nicotine inhibited RBC hemolysis by 36.7% at the highest concentration used, but increased RBC hemolysis at the lower concentrations. Cotinine caused a 13.8% increase in RBC membrane peroxidation at the highest concentration used and its effects were dose-dependent. At their highest concentrations, nicotine and cotinine decreased -SH groups by 50%. CONCLUSIONS The present study confirms the results from previous studies of the oxidative and destructive effects of cigarette smoke, which are detrimental to the health of both active and passive smokers.