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Fragmentation of a linoleate-derived ?-hydroperoxy-?,?-unsaturated epoxide to ?-hydroxy- and ?-oxo-alkenals involves a unique pseudo-symmetrical diepoxycarbinyl radical.

ABSTRACT: Many of the pathological effects of lipid peroxidation are mediated by aldehydes generated through fragmentation of lipid peroxides. Among these aldehydes, the ?-hydroxy- and ?-oxo-?,?-alkenals, e.g., 4-hydroxy-2-nonenal (HNE) and 4-oxo-2-nonenal (ONE), are especially prone to modifying proteins and DNA through covalent adduction. In addition the "mirror image" ?-hydroxy- and ?-oxo-?,?-alkenal phospholipids can serve as high-affinity ligands for biological receptors triggering pathology. Therefore, the mechanisms by which these aldehydes are generated in vivo are under intense scrutiny. We now report observations supporting the intermediacy of a unique pseudo-symmetrical diepoxycarbinyl radical that accounts for the coproduction of HNE, ONE, and their mirror image analogues 9-hydroxy-12-oxo-10(E)-dodecenoic acid and 9-keto-12-oxo-10-dodecenoic acid upon fragmentation of 13-hydroperoxy-cis-9,10-epoxyoctadeca-11-enoic acid.

SUBMITTER: Gu X

PROVIDER: S-EPMC3733989 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Fragmentation of a linoleate-derived γ-hydroperoxy-α,β-unsaturated epoxide to γ-hydroxy- and γ-oxo-alkenals involves a unique pseudo-symmetrical diepoxycarbinyl radical.

Gu Xiaodong X Salomon Robert G RG

Free radical biology & medicine 20111201 3

Many of the pathological effects of lipid peroxidation are mediated by aldehydes generated through fragmentation of lipid peroxides. Among these aldehydes, the γ-hydroxy- and γ-oxo-α,β-alkenals, e.g., 4-hydroxy-2-nonenal (HNE) and 4-oxo-2-nonenal (ONE), are especially prone to modifying proteins and DNA through covalent adduction. In addition the "mirror image" γ-hydroxy- and γ-oxo-α,β-alkenal phospholipids can serve as high-affinity ligands for biological receptors triggering pathology. Therefo ...[more]

PMID: 22155057

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Dataset Information

Fragmentation of a linoleate-derived ?-hydroperoxy-?,?-unsaturated epoxide to ?-hydroxy- and ?-oxo-alkenals involves a unique pseudo-symmetrical diepoxycarbinyl radical.

Publications

Fragmentation of a linoleate-derived γ-hydroperoxy-α,β-unsaturated epoxide to γ-hydroxy- and γ-oxo-alkenals involves a unique pseudo-symmetrical diepoxycarbinyl radical.

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