Suppressive effect of carotenoids on the luminol dependent chemiluminescence of the stimulated rat macrophages.

Rat macrophages stimulated by phorbol 12-myristate 13-acetate (PMA) produced significant chemiluminescence in luminol. Carotenoids suppressed the luminol-dependent chemiluminescence at the beginning and after two minutes of the stimulation. Canthaxanthin and bixin had higher suppressive activity that beta-carotene and lutein. The measurement of the absorption spectra of carotenoids showed that the absorption by carotenoids was diminished during the stimulation of macrophages. The results suggest that the suppressive effect of carotenoids may be due to their scavenging the reactive oxygen metabolites released by macrophages.