5-Lipoxygenase and 12-Lipoxygenase (5-LO and 12-LO (sometimes also ALOX5 and ALOX12, respectively))

5-Lipoxygenase (5-LO) and 12-Lipoxygenase (12-LO) are members of the lipoxygenase (LOX) enzyme family that catalyze the dioxygenation of polyunsaturated fatty acids, primarily arachidonic acid, to bioactive lipid mediators. 5-LO is the key enzyme in leukotriene biosynthesis, which are potent mediators of inflammation and allergy, and also contributes to the production of specialized pro-resolving mediators involved in resolution of inflammation[1][3][4][8]. In addition to its catalytic role, 5-LO can translocate to the nucleus and influence gene expression and microRNA processing[1]. 12-LO catalyzes the formation of 12-hydroperoxyeicosatetraenoic acid (12-HpETE) and is involved in cellular processes such as platelet aggregation, maintenance of the skin barrier, and neuronal injury[5][6][7]. Both enzymes have been implicated in the pathogenesis of inflammatory conditions (e.g., asthma, atherosclerosis), some cancers, and, for 12/15-LOX, neurodegenerative diseases and ischemic injury. Drugs targeting these enzymes primarily aim to reduce pro-inflammatory and pro-oxidative mediator production (e.g., zileuton for 5-LO, ML351 for 12/15-LOX inhibition). The target "5-Lipoxygenase and 12-Lipoxygenase" as a single entity is imprecise, as these are distinct enzymes with related but non-identical substrates, actions, and clinical implications[5]; thus, proper distinction between "5-Lipoxygenase" and "12-Lipoxygenase" is recommended for precise database structuring.

Other names

5-LO (for 5-Lipoxygenase)ALOX5 (for 5-Lipoxygenase gene/protein)12-LO (for 12-Lipoxygenase)ALOX12 (for 12-Lipoxygenase gene/protein)Platelet-type 12-Lipoxygenase (for 12-LO)Lipoxygenases (family)

Inhibition of leukotriene biosynthesis (by blocking 5-LO) - Suppression of pro-inflammatory eicosanoid production - Inhibition of prostaglandin export (by some 5-LO inhibitors) - Neuroprotection via 12/15-LOX inhibition - Modulation of microRNA maturation (5-LO, less commonly targeted)