Endogenous metabolites of vitamin E limit inflammation by targeting 5-lipoxygenase

Pein H, Ville A, Pace S, Temml V, Garscha U, Raasch M, Alsabil K, Viault G, Dinh CP, Guilet D, Troisi F, Neukirch K, König S, Bilancia R, Waltenberger B, Stuppner H, Wallert M, Lorkowski S, Weinigel C, Rummler S, Birringer M, Roviezzo F, Sautebin L, Helesbeux JJ, Séraphin D, Mosig AS, Schuster D, Rossi A, Richomme P, Werz O, Koeberle A

Abstract

Systemic vitamin E metabolites have been proposed as signaling molecules, but their physiological role is unknown. Here we show, by library screening of potential human vitamin E metabolites, that long-chain ω-carboxylates are potent allosteric inhibitors of 5-lipoxygenase, a key enzyme in the biosynthesis of chemoattractant and vasoactive leukotrienes. 13-((2R)-6-hydroxy-2,5,7,8-tetramethylchroman-2-yl)-2,6,10-trimethyltridecanoic acid (α-T-13′-COOH) can be synthesized from α-tocopherol in a human liver-on-chip, and is detected in human and mouse plasma at concentrations (8-49 nM) that inhibit 5-lipoxygenase in human leukocytes. α-T-13′-COOH accumulates in immune cells and inflamed murine exudates, selectively inhibits the biosynthesis of 5-lipoxygenase-derived lipid mediators in vitro and in vivo, and efficiently suppresses inflammation and bronchial hyper-reactivity in mouse models of peritonitis and asthma. Together, our data suggest that the immune regulatory and anti-inflammatory functions of α-tocopherol depend on its endogenous metabolite α-T-13′-COOH, potentially through inhibiting 5-lipoxygenase in immune cells.

Read More