Differential inhibition of arachidonate cyclo-oxygenase and lipoxygenase enzymes by drugs and new approaches to anti-inflammatory therapy

ABSTRACT

We have compared the effects of various types of drugs on arachidonate cyclo-oxygenase and lipoxygenase enzymes. Several non-steroidal anti-inflammatory drugs [NSAID] were found to be predominant inhibitors of cyclo-oxygenase and had little or no effect on the lipoxygenase activity. On the other hand, anti-malarial drugs and various anti-oxidants inhibited both enzymes with varying potencies whereas anti-asthmatic drugs and anti-inflammatory steroids showed no effect. These results are demonstrative that metabolism of arachidonic acid by way of cyclo-oxygenase and lipoxygenase pathways are involved in inflammation, and that dual inhibition of cyclo- oxygenase and lipoxygenase may lead to a more selective type of anti-inflammatory action without the complicating side-effects of corticosteroids