The anti-inflammatory and antinociceptive actions of the protein fraction from the latex were reflected in the effects observed in experimental arthritis models, where the dose of 50 mg/kg iv reduced cell influx, myeloperoxidase activity, nitric oxide levels, inflammatory cytokines (interleukin (IL)-1β and IL-6), and edema caused by zymosan-induced arthritis (7,8). This evidence concerns the gene MPO and arthritic joint disease.