Neuroprostanes

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The neuroprostanes are prostaglandin-like compounds formed in vivo from the free radical-catalyzed peroxidation of essential fatty acids (primarily docosahexaenoic acid) without the direct action of cyclooxygenase (COX) enzymes. The result is the formation of isoprostane-like compounds F4-, D4-, E4-, A4-, and J4-neuroprostanes which have been shown to be produced in vivo [1] . These oxygenated essential fatty acids possess potent biological activity as anti-inflammatory mediators inhibiting the response of human macrophages that augment the perception of pain [2] .


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GPR132 protein-coding gene in the species Homo sapiens

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13-Hydroxyoctadecadienoic acid chemical compound

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9-Hydroxyoctadecadienoic acid chemical compound

9-Hydroxyoctadecadienoic acid has been used in the literature to designate either or both of two stereoisomer metabolites of the essential fatty acid, linoleic acid: 9(S)-hydroxy-10(E),12(Z)-octadecadienoic acid and 9(R)-hydroxy-10(E),12(Z)-octadecadienoic acid ; these two metabolites differ in having their hydroxy residues in the S or R configurations, respectively. The accompanying figure gives the structure for 9(S)-HETE. Two other 9-hydroxy linoleic acid derivatives occur in nature, the 10E,12E isomers of 9(S)-HODE and 9(R)-HODE viz., 9(S)-hydroxy-10E,12E-octadecadienoic acid and 9(R)-hydroxy-10E,12E-octadecadienoic acid ; these two derivatives have their double bond at carbon 12 in the E or trans configuration as opposed to the Z or cis configuration. The four 9-HODE isomers, particularly under conditions of oxidative stress, may form together in cells and tissues; they have overlapping but not identical biological activities and significances. Because many studies have not distinguished between the S and R stereoisomers and, particularly in identifying tissue levels, the two EE isomers, 9-HODE is used here when the isomer studied is unclear.

Specialized pro-resolving mediators are a large and growing class of cell signaling molecules formed in cells by the metabolism of polyunsaturated fatty acids (PUFA) by one or a combination of lipoxygenase, cyclooxygenase, and cytochrome P450 monooxygenase enzymes. Pre-clinical studies, primarily in animal models and human tissues, implicate SPM in orchestrating the resolution of inflammation. Prominent members include the resolvins and protectins.

References

  1. Jacson, Roberts (2005). "The biochemistry of the isoprostane, neuroprostane, and isofuran Pathways of lipid peroxidation". Brain Pathology. 15 (2): 143–148. doi:10.1111/j.1750-3639.2005.tb00511.x. PMID   15912887. S2CID   43236072.
  2. Gladine, Laurie (2014). "Neuroprostanes, produced by free-radical mediated peroxidation of DHA, inhibit the inflammatory response of human macrophages" (PDF). Free Radic. Biol. 75 (S1): S15. doi:10.1016/j.freeradbiomed.2014.10.590. PMID   26461294.