Differential inhibition of matrix metalloproteinases-2, -9, and -13 activities by selected anthraquinones.

Matrix metalloproteinases (MMPs) play an important role in physiological and pathological matrix remodeling. Here, we report that the natural anthraquinones, emodin, emodic acid, chrysazin, physcion, and rhein differentially inhibit several members of this enzyme family, the gelatinases MMP-2 and -9, and the collagenase MMP-13. The IC50 values determined by measuring the activities of human recombinant catalytic domains of these enzymes varied in the micromolar range. Emodin and emodic acid most potently inhibited MMP-9 with IC50 values of 15 and 10 microM, respectively. With MMP-13, emodic acid was 3-times less potent than emodin which showed a similar IC50 value (13 microM) as chrysazin. These results are of interest in view of the widespread medicinal use of anthraquinones and their derivatives.