Phenolic constituents from Yucca schidigera inhibit COX-1, COX-2 and 5-LOX in vitro

Abstract

Yucca schidigera Roezl (Agavaceae) is a plant native to the South-Western United States and Mexico. It has been used for centuries in traditional medicine against a variety of inflammatory disorders like headaches, gonorrhoea, arthritis and rheumatism. Apart from a high level of saponins, the plant contains considerable amounts of phenolics which occur in the stem bark [1]. In order to investigate the anti-inflammatory potential of this plant, we have tested a yucca bark extract concentrated of phenolics, as well as the major phenolic constituents of this extract, resveratrol (1), trans-3,3',5,5'-tetrahydroxy-4'-methoxystilbene (2) and yuccaols A (3), B (5) and C (4), for their inhibitory activity against cyclooxygenase (COX)-1, COX-2 and 5-lipoxygenase (LOX) [2,3]. The extract significantly inhibited all three enzymes (IC50 COX-1 18.48µg/ml, COX-2 65.95µg/ml and 5-LOX 42.22µg/ml). The pure compounds also inhibited COX-1, COX-2 and 5-LOX to a different extent. In general, they were more active against COX-1 than against COX-2 and 5-LOX, and the inhibitory potential seems to be strongly influenced by the substitution of ring B in the stilbenic moiety.