title: Ability of 15-hydroxyeicosatrienoic acid (15-OH-20:3) to modulate macrophage arachidonic acid metabolism.
abstract: Mouse peritoneal macrophages metabolize dihomogammalinolenic acid (20:3n-6) primarily to 15-hydroxy-8,11,13-eicosatrienoic acid (15-OH-20:3). Since the biological properties of this novel trienoic eicosanoid remain poorly defined, the effects of increasing concentrations of 15-OH-20:3 and its arachidonic acid (20:4n-6) derived analogue. 15-hydroxy-5,8,11,13-eicosatetraenoic acid (15-HETE), on mouse macrophage 20:4n-6 metabolism were investigated. Resident peritoneal macrophages were prelabeled with [3H]-20:4n-6 and subsequently stimulated with zymosan in the presence of either 15-OH-20:3 or 15-HETE (1-30 microM). After 1 hr, the radiolabeled soluble metabolites were analyzed by reverse phase high performance liquid chromatography. 15-OH-20:3 inhibited zymosan-induced leukotriene C4 (IC50 = 2.4 microM) and 5-HETE (IC50 = 3.1 microM) synthesis. In contrast to the inhibition of macrophage 5-lipoxygenase, 15-OH-20:3 enhanced 12-HETE synthesis (5-30 microM) and had no measurable effect on cyclooxygenase metabolism (1-10 microM) i.e., 6-keto-prostaglandin F1 alpha and prostaglandin E2 synthesis. Addition of exogenous 15-HETE produced similar effects. These results suggest that the manipulation of macrophage 15-OH-20:3n-6 levels may provide a measure of cellular control over 20:4n-6 metabolism, specifically, leukotriene production.
mesh_terms: D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism* / Q000494:pharmacology*; D006880:Hydroxy Acids / Q000378:metabolism; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D013189:SRS-A / Q000096:biosynthesis
chemical_list: D001095:Arachidonic Acids; D005231:Fatty Acids, Unsaturated; D006880:Hydroxy Acids; D006893:Hydroxyeicosatetraenoic Acids; D013189:SRS-A; C035510:15-hydroxy-8,11,13-eicosatrienoic acid; D016718:Arachidonic Acid; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid; D015126:8,11,14-Eicosatrienoic Acid