Regulation and metabolism of arachidonic acid

Summary The metabolism of AA reflects a carefully balanced series of biochemical pathways. The level of free arachidonate in a cells is controlled byde novo synthesis, dietary uptake, and transcellular metabolism. Lysophospholipids are key controlling substrates for a variety of acyl transferase and transacylase reactions, whose combined effect is to remodel cellular membranes placing AA in up to 20 different molecular species of phospholipids. PLA₂ enzymes, both cytosolic and secretory, can release AA for subsequent metabolism via lipoxygenase, COX, and cytochrome P450 enzymes into a variety of eicosanoid products. Reactions are often tissue- and cell-specific, and provide a spectrum of inflammatory mediator release in which many of the molecular details remain to be elucidated.