CIGARETTE-SMOKING INFLUENCES CYTOKINE PRODUCTION AND ANTIOXIDANT DEFENSES

1. Smoking exerts an inflammatory stimulus on lung macrophages, and sm okers generally have low intakes of antioxidant micronutrients. This s tudy was performed to investigate the relationship between whole-blood tumour necrosis factor production, plasma interleukin-6 and acute-pha se protein concentration and antioxidant vitamins in smokers and non-s mokers. 2. Measurement of tumour necrosis factor was conducted in whol e blood stimulated with endotoxin (lipopolysaccharide), and interleuki n-6 concentrations were measured in the plasma of smokers and nonsmoke rs. Enzyme and dietary antioxidant concentrations and acute-phase prot eins were determined in the two groups. 3. Tumour necrosis factor prod uction and plasma interleukin-6 concentrations were 38% (P=0.01) and 1 6% (P=0.07) greater, respectively, in smokers than in non-smokers. Pla sma vitamin A and E concentrations were unaffected by smoking; however , a 21% lower plasma vitamin C (P=0.04) concentration was observed in smokers, than in non-smokers despite a similar intake of this vitamin by the two groups. 4. Concentrations of the acute-phase proteins alpha (1)-acid glycoprotein, caeruloplasmin and alpha(2)-macroglobulin were increased in the plasma of smokers compared with non-smokers by 39%, 2 8%, and 12% respectively (P<0.01). Our studies indicate that smokers h ave a compromised antioxidant status and elevated concentrations of tu mour necrosis factor and interleukin-6 as a consequence of smoking. 5. These observations may provide some insight into the biological mecha nisms underlying the pathology associated with smoking.