trans Arachidonic acid isomers inhibit NADPH-oxidase activity by direct interaction with enzyme components

H. Souabni, V. Thoma, T. Bizouarn, C. Chatgilialoglu, A. Siafaka-Kapadai, L. Baciou, C. Ferreri, C. Houée-Levin, M. A. Ostuni

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)

Abstract

NADPH-oxidase is an enzyme that represents, when activated, the major source of non-mitochondrial reactive oxygen species. In phagocytes, this production is an indispensable event for the destruction of engulfed pathogens. The functional NADPH-oxidase complex consists of a catalytic membrane flavocytochrome b (Cytb558) and four cytosolic proteins p47 phox, p67phox, Rac and p40phox. The NADPH-oxidase activity is finely regulated spatially and temporally by cellular signaling events that trigger the translocation of the cytosolic subunits to its membrane partner involving post-translational modifications and activation by second messengers such as arachidonic acid (AA). Arachidonic acid in its natural cis-poly unsaturated form (C20:4) has been described to be an efficient activator of the enzyme in vivo and in vitro. In this work, we examined in a cell-free system whether a change of the natural cis geometry to the trans configuration, which could occur either by diet or be produced by the action of free radicals, may have consequences on the functioning of NADPH-oxidase. We showed the inability of mono-trans AA isomers to activate the NADPH-oxidase complex and demonstrated the inhibitory effect on the cis-AA-induced NADPH oxidase activation. The inhibition is mediated by a direct effect of the mono-trans AA which targets both the membrane fraction containing the cytb 558 and the cytosolic p67phox. Our results suggest that the loss of the natural geometric feature (cis-AA) induces substantial structural modifications of p67phox that prevent its translocation to the complex.

Original languageEnglish
Pages (from-to)2314-2324
Number of pages11
JournalBiochimica et Biophysica Acta - Biomembranes
Volume1818
Issue number9
DOIs
Publication statusPublished - 2012 Sep
Externally publishedYes

Keywords

  • Arachidonic acid
  • Cell free system
  • NADPH oxidase
  • Protein complex assembly
  • Superoxide production inhibition
  • trans Fatty acid

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Cell Biology

Fingerprint Dive into the research topics of 'trans Arachidonic acid isomers inhibit NADPH-oxidase activity by direct interaction with enzyme components'. Together they form a unique fingerprint.

Cite this