lipoxin b4

Lipoxin B4是花生四烯酸的代谢产物，能够抑制上呼吸道中的鼻粘膜中的白细胞浸润和粘液分泌，具有粘膜保护作用，常用于研究上、下呼吸道的过敏性炎症。

Lipoxin B4 (LXB4) methyl ester is a lipid soluble prodrug form of the transcellular metabolite LXB4 . LXB4 is a positional isomer of LXA4 produced by the metabolism of 15-HETE or 15-HpETE by human leukocytes. At a concentration of 100 nM, LXB4 inhibits polymorphonuclear leukocyte (PMN) migration stimulated by leukotriene B4 and inhibits LTB4-induced adhesion of PMNs with an IC50 value of 0.3 nM.

Lipoxin A4 methyl ester (LXA4 methyl ester) is a more lipid soluble, prodrug formulation of the transcellular metabolite LXA4. LXA4 is a trihydroxy fatty acid containing a conjugated tetraene, produced by the metabolism of 15-HETE or 15-HpETE with human leukocytes.[1] LXA4 is equipotent to leukotriene B4 (LTB4) in inducing superoxide generation in human neutrophils at 0.1 μM.[2] LXA4 is associated with several other biological functions including leukocyte activation, chemotaxis effects, natural killer cell inhibition, and monocyte migration and adhesion.[2],[3],[4]

15(R)-HETE, a monohydroxy fatty acid, is synthesized from arachidonic acid via aspirin-acetylated COX-2, leading to the formation of specialized pro-resolving mediators 15(R)-lipoxin A4 and B4 through a transcellular mechanism involving 5-lipoxygenase (5-LO). Additionally, this compound is produced by the cytochrome P450 (CYP) isoform CYP2C9 and can be generated from arachidonic acid by COX-1 in human mast cells, where it accumulates due to its resistance to conversion into 15-KETE by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). As an agonist of PPARβ δ, 15(R)-HETE induces the expression of a target gene in NIH3T3 cells, demonstrating its biological significance.