title: Michael adducts of palmitoylascorbic acid: effects on the oxidative burst of neutrophils and the production of tumor necrosis factor-alpha in monocytes.
abstract: The effects of Michael adducts of 6-O-palmitoyl-L-ascorbic acid (compounds 1-4) on the phosphorylation-dependent response of stimulated monocytes and neutrophils was investigated. The pyranosyl derivative 3 increased the production of tumor necrosis factor-alpha in human monocytes stimulated with lipopolysaccharide (LPS). Compound 3 also enhanced the release of tumor necrosis factor-alpha from nonstimulated monocytes. Michael adducts 1-4 inhibited the formation of reactive oxygen species in fMLP-stimulated human neutrophils as measured by luminol chemiluminescence. Treatment with 6-O-palmitoyl-L-ascorbic acid (compound 5) also led to a decreased luminescence response of neutrophils. Results are discussed with respect to the inhibitory activity of Michael adducts of ascorbic acids towards protein phosphatases PP1/PP2A.
authors.affiliation: Pharmaceutical Institute, Poppelsdorf, University of Bonn, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Gütschow
authors.forename: Sunna
authors.initials: S
authors.lastname: Hauschildt
authors.forename: Stefan
authors.initials: S
authors.lastname: Benard
authors.forename: Sabine
authors.initials: S
authors.lastname: Reichl
authors.forename: Uta G
authors.initials: UG
authors.lastname: Witt
authors.forename: Kurt
authors.initials: K
authors.lastname: Eger
authors.forename: Jürgen
authors.initials: J
authors.lastname: Arnhold
mesh_terms: D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D006801:Humans; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D016897:Respiratory Burst / Q000187:drug effects* / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D001205:Ascorbic Acid; C031226:6-O-palmitoylascorbic acid