Lipoxin

From Biology-Online Dictionary | Biology-Online Dictionary

Definition

noun, plural: lipoxins

Any member from the subfamily of eicosanoids, with a chemical formula of C20H32O5, and involved in the regulation of inflammatory responses


Supplement

Eicosanoid is the generic term to refer to the compounds derived from arachidonic acid or other polyunsaturated fatty acids of 20-carbon length. Some of the prominent eicosanoids include (1) eoxins, (2) leukotrienes, (3) lipoxins, (4) prostacyclin, (5) prostaglandins, (6) resolvins, and (7) thromboxanes.

Lipoxins belong to a subfamily of eicosanoids that have a chemical formula of C20H32O5. They are produced by various cells. They regulate inflammation. There are two chemically identified lipoxins: lipoxin A4 (LXA4) and lipoxins B4 (LXB4). They were first observed to be produced by human neutrophils.

Pro-inflammatory arachidonic acid metabolites and certain cytokines (e.g. IFN-γand IL-1β) stimulate the biosynthesis of lipoxins. Lipoxins are derived from arachidonic acid, through the enzyme, 15-lipoxygenase.

Lipoxins may also be categorized as a subgroup of polyunsaturated fatty acid metabolites. In this regard, they belong to the specialized pro-resolving mediators (SPMs) characterized by being arachidonic acid metabolites having four double bonds and three hydroxyl residues. The SPMs are formed to stimulate cells and tissues that would reverse the actions of pro-inflammatory mediators so that the inflammatory response is dampened and reversed, and so that tissue repair will be initiated.


IUPAC name:

  • 5S,14R,15S-Trihydroxy-6E,8Z,10E,12E -eicosatetraenoic acid

Chemical formula:

  • C20H32O5

Abbreviation:

  • LX

See also: