Inhibition of arachidonate lipoxygenase activities by 2-(3,4-dihydroxyphenyl)ethanol, a phenolic compound from olives.
The effects of olive fruit extract on arachidonic acid lipoxygenase activities were investigated using rat platelets and rat polymorphonuclear leukocytes (PMNL). Olive extract strongly inhibited both 12-lipoxygenase (12-LO) and 5-lipoxygenase (5-LO) activities. One of the compounds responsible for this inhibition was purified and identified as 2-(3,4-dihydroxyphenyl)ethanol (DPE). DPE inhibited platelet 12-LO activity (IC50, 4.2 microM) and PMNL 5-LO activity (IC50, 13 microM) but not cyclooxygenase activity in cell-free conditions. It also inhibited 12-LO activity in intact platelets (IC50, 50 microM) and reduced leukotriene B4 production in intact PMNL stimulated by A23187 (IC50, 26 microM). The inhibition by DPE of both lipoxygenase activities was stronger than that by oleuropein, caffeic acid, or 7 other related phenolic compounds, especially in intact cells. These results suggest that DPE is a potent specific inhibitor of lipoxygenase activities.
Kohyama
N
N
Shikoku National Agricultural Experiment Station, Kagawa, Japan.
Nagata
T
T
Fujimoto
S
S
Sekiya
K
K
D000818:Animals; D001091:Arachidonate Lipoxygenases / Q000037:antagonists & inhibitors*; D016718:Arachidonic Acid / Q000378:metabolism; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005638:Fruit; D015394:Molecular Structure; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000494:pharmacology; D010936:Plant Extracts; D051381:Rats; D017208:Rats, Wistar
D004791:Enzyme Inhibitors; D010936:Plant Extracts; C005975:3,4-dihydroxyphenylethanol; D016718:Arachidonic Acid; D001091:Arachidonate Lipoxygenases; D010626:Phenylethyl Alcohol