Reference

Prostaglandin H-synthase-2 is the main enzyme involved in the biosynthesis of octadecanoids from linoleic acid in human dermal fibroblasts stimulated with interleukin-1b

Prostaglandin H-synthase-2 is the main enzyme involved in the biosynthesis of octadecanoids from linoleic acid in human dermal fibroblasts stimulated with interleukin-1b. Godessart, Nuria; Camacho, Mercedes; Lopez-Belmonte, Jesus; Anton, Rosa; Garcia, Montserrat; De Moragas, Josep-Maria; Vila, Luis (Institute Research, Santa Creu i Sant Pau Hospital, Barcelona, Spain). Journal of Investigative Dermatology, 107(5), 726-732 (English) 1996 Blackwell. CODEN: JIDEAE. ISSN: 0022-202X. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) This study was focused on the characterization of the metab. of linoleic acid by human dermal fibroblasts and the effect of interleukin-1 on the biosynthesis of octadecanoids. Dermal fibroblasts untreated and treated with recombinant IL-1b were incubated with exogenous labeled linoleic acid. A combination of high performance liq. chromatog. and gas chromatog.Several reagents with their cas registry numbers 98524-19-7 and 10075-11-3 are used here.-mass spectrometry was used as the analytic technique. The authors found that dermal fibroblasts convert linoleic acid mainly into 13-hydroxy-9-cis,11-trans-octadecadienoic acid (13-HODE) and 9-hydroxy-10-trans,12-cis-octadecadienoic acid (9-HODE), 13(S)-HODE and 9(R)-HODE being the predominant enantiomers. IL-1b increased the formation of both 13-HODE and 9-HODE in a concn.-dependent manner with similar EC50 values as for prostanoid formation. This effect of IL-1b on HODEs formation was concomitant with the expression of prostaglandin H-synthase-2. Formation of octadecanoids was inhibited in a concn.-dependent manner by acetylsalicylic acid and indomethacin. Dexamethasone, actinomycin D, and cycloheximide abolished the effect of IL-1b on HODEs biosynthesis. Octadecanoid biosynthetic activity was assocd. with the microsomal fraction. Dermal fibroblasts incorporated [14C]-9-HODE and [14C]-13-HODE into phospholipids, mainly into phosphatidylcholine. IL-1b increased significantly the esterification of 13-HODE in all glycerophospholipids, the major increase being obsd. in phosphatidylinositol. These results indicate that prostaglandin H-synthase-2 is the enzyme responsible for the increase in the ability to form HODEs of dermal fibroblasts stimulated with IL-1b. .

Preferential formation of 13-hydroxylinoleic acid by human peripheral blood eosinophils

Preferential formation of 13-hydroxylinoleic acid by human peripheral blood eosinophils. Engels, F.; Kessels, G. C. R.; Henricks, P. A.Chemicals with cas numbers 67030-67-5 and 98524-19-7 also play role. J.; Nijkamp, F. P. (Dep. Pharmacol., Utrecht Inst. Pharmaceutical Sci., Utrecht Univ., Neth.). Prostaglandins, 52(2), 117-124 (English) 1996 Elsevier. CODEN: PRGLBA. ISSN: 0090-6980. DOCUMENT TYPE: Journal CA Section: 13 (Mammalian Biochemistry) Lipid mediators released by inflammatory and immune cells play an important role in inflammatory and immune processes. Most attention has been focussed on arachidonic-derived mediators, including prostaglandins, thromboxanes, leukotrienes, and lipoxins. Literature data, however, suggest that metabolites of the unsatd. fatty acid linoleic acid may also be important in this respect. The formation and release of 9-hydroxy- and 13-hydroxy-linoleic acid (9-HODE and 13-HODE) were studied here by enriched populations of human peripheral blood neutrophils, eosinophils, basophils, monocytes, and lymphocytes. It is demonstrated that the eosinophil preferentially produces 13-HODE, whereas the other cell types produce equal amts. of 9-HODE and 13-HODE. The biol. significance of these findings is discussed. .