Eoxin A4

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Eoxin A4
Names
Preferred IUPAC name
(5Z,8Z,10E,12E)-13-[(2S,3S)-3-Pentyloxiran-2-yl]trideca-5,8,10,12-tetraenoic acid
Other names
EXa4; 14,15-LTA4
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
  • InChI=1S/C20H30O3/c1-2-3-12-15-18-19(23-18)16-13-10-8-6-4-5-7-9-11-14-17-20(21)22/h4,6-10,13,16,18-19H,2-3,5,11-12,14-15,17H2,1H3,(H,21,22)/b6-4-,9-7-,10-8+,16-13+/t18-,19-/m0/s1
    Key: URDQSJSEGRMOIT-FDMWOPBLSA-N
  • CCCCC[C@H]1[C@@H](O1)/C=C/C=C/C=C\C/C=C\CCCC(=O)O
Properties
C20H30O3
Molar mass 318.457 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Eoxin A4, also known as 14,15-leukotriene A4, is an eoxin. Cells make eoxins by metabolizing arachidonic acid with a 15-lipoxygenase enzyme to form 15(S)-hydroperoxyeicosapentaenoic acid (i.e. 15(S)-HpETE). This product is then converted serially to eoxin A4 (i.e. EXA4), EXC4, EXD4, and EXE4 by LTC4 synthase, an unidentified gamma-glutamyltransferase, and an unidentified dipeptidase, respectively, in a pathway which appears similar if not identical to the pathway which forms leukotreines, i.e. LTA4, LTC4, LTD4, and LTE4. This pathway is schematically shown as follows:[1][2]

Arachidonic acid + O2 → 15(S)-HpETE → EXA4 → EXC4 → EXD4 → EXE4

EXA4 is viewed as an intracellular-bound, short-lived intermediate which is rapidly metabolized to the down-stream eoxins. The eoxins down stream of EXA4 are secreted from their parent cells and, it is proposed but not yet proven, serve to regulate allergic responses and the development of certain cancers (see Eoxins).[1][3]

References

  1. ^ a b Claesson HE (September 2009). "On the biosynthesis and biological role of eoxins and 15-lipoxygenase-1 in airway inflammation and Hodgkin lymphoma". Prostaglandins Other Lipid Mediat. 89 (3–4): 120–5. doi:10.1016/j.prostaglandins.2008.12.003. PMID 19130894.
  2. ^ Greene ER, Huang S, Serhan CN, Panigrahy D (2011). "Regulation of inflammation in cancer by eicosanoids". Prostaglandins & Other Lipid Mediators. 96 (1–4): 27–36. doi:10.1016/j.prostaglandins.2011.08.004. PMC 4051344. PMID 21864702.
  3. ^ Feltenmark S, Gautam N, Brunnström A, Griffiths W, Backman L, Edenius C, Lindbom L, Björkholm M, Claesson HE (2008). "Eoxins are proinflammatory arachidonic acid metabolites produced via the 15-lipoxygenase-1 pathway in human eosinophils and mast cells". Proceedings of the National Academy of Sciences of the United States of America. 105 (2): 680–5. Bibcode:2008PNAS..105..680F. doi:10.1073/pnas.0710127105. PMC 2206596. PMID 18184802.