CHAMAZULENE - AN ANTIOXIDANT-TYPE INHIBITOR OF LEUKOTRIENE B-4 FORMATION

Matricine and its transformation product chamazulene are constituents of chamomile extracts. Both have been demonstrated to exert anti-infla mmatory activity in vivo. Since preparations from chamomile are used f or the treatment of inflammatory skin and bowel diseases, we studied t he effects of these compounds on the leukotriene production in neutrop hilic granulocytes. Chamazulene inhibited the formation of leukotriene B-4 in intact cells and in the 105,000 x g supernatant fraction in a concentration-dependent manner. The IC50 values were 15 and 10 mu M, r espectively. Matricine showed no effect up to 200 mu M. Chamazulene (I C50: 2 mu M), but not matricine, blocked the chemical peroxidation of arachidonic acid. Additionally, matricine (up to 200 mu M) had no effe cts on the cyclooxygenase and 12-lipoxygenase activities in human plat elets. Therefore, it is concluded that chamazulene, but not matricine, may contribute to the anti-inflammatory activity of chamomile extract s by inhibiting the leukotriene synthesis and additional antioxidative effects.