Definition | 15(S)-HETE is a hydroxyeicosatetraenoic acid. Hydroxyeicosatetraenoic acids (HETEs) are formed by the 5-, 12- and 15-lipoxygenase (LO) pathways. 5- and 12-LO products are mainly proinflammatory in the skin whereas the main 15-LO product 15-HETE has antiinflammatory capacities. In vitro 15-HETE has been shown to inhibit LTB4 formation, 12-HETE formation and specifically inhibits the neutrophil chemotactic effect of LTB4. The inhibition of LTB4 formation is probably due to modulation of the 5-LO because no changes in PGE2 formation have been determined. In vivo, 15-HETE inhibits LTB4-induced erythema and edema, and reduces LTB4 in the synovial fluid of carragheenan-induced experimental arthritis in dogs. 15-HETE has also some immunomodulatory effects. It inhibits the mixed lymphocyte reaction, induces generation of murine cytotoxic suppressor T cells, and it decreases interferon production by murine lymphoma cells. Furthermore, IL-4 and IL-13 have recently been shown to be potent activators of the 15-LO in mononuclear cells. (PMID: 11104340 ) [HMDB] |
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