PLASMA-LEVELS OF BETA-CAROTENE ARE INVERSELY CORRELATED WITH CIRCULATING NEUTROPHIL COUNTS IN YOUNG MALE CIGARETTE SMOKERS

Relationships between plasma levels of beta-carotene (BC) and the numb ers and oxidant-generating activities of circulating neutrophils have been investigated in a group of asymptomatic young male cigarette smok ers (N = 40) and in a group of nonsmoking control subjects. Plasma BC levels were measured using HPLC, while oxidant generation was measured using a phorbol myristate acetate (PMA) activated whole blood luminol -enhanced chemiluminescence (LECL) method. Relative to nonsmokers, the numbers of circulating neutrophils, as well as the LECL responses of these cells, were increased by 41% (p = 0.0001) and 47% (p = 0.004), r espectively, while plasma BC levels were decreased by 24% (p = 0.01). In cigarette smokers, but not in nonsmokers, the numbers of circulatin g neutrophils, as well as the LECL responses of these cells, were sign ificantly and inversely correlated with plasma BC levels (r = -0.36, p = 0.02; and r = -0.33, P = 0.04 respectively). Diminished plasma leve ls of BC in cigarette smokers probably reflect the increased numbers a nd prooxidative activities of circulating neutrophils. Intake of this antioxidant nutrient may be a determinant of susceptibility to smoking -related pulmonary dysfunction mediated by oxidants derived from smoke -activated phagocytes.