EFFECT OF 3'-HYDROXYFARREROL ON AIRWAY HYPERREACTIVITY INDUCED BY ACUTE CIGARETTE-SMOKE EXPOSURE IN GUINEA-PIGS

The (+/-)-3'-hydroxyfarrerol (IdB 1031) is a new drug endowed with an interesting mucokinetic activity. In this study the effectiveness of I dB 1031 has been verified in a model of airway hyperreactivity and lun g inflammation induced in anaesthetized guinea pig by active cigarette smoke exposure. IdB 1031 (500 mg/kg per os) completely inhibited the capacity of cigarette smoke to induce airway hyperreactivity. IdB 1031 also inhibited the recruitment of proinflammatory cells within the ai rway lumen as showed in bronchoalveolar lavage fluids. In line with th ese experiments IdB 1031 inhibited 5-lipoxygenase with an IC50 of 7.36 x 10(-6) M in human leukocytes challenged by A-23187 (2 mu M). A sign ificant reduction of the above parameters was observed also in animals exposed to smoke after repeated treatment with IdB 1031 at 200 mg/kg per os for 15 days. These results show that IdB 1031 is a promising dr ug with a favourable spectrum of activities on the respiratory tract.