Gliadin increases iNOS gene expression in interferon-gamma-stimulated RAW 264.7 cells through a mechanism involving NF-kappa B.
Nitric oxide (NO) plays an important role in the pathogenesis of the histological changes seen in coeliac disease. We have investigated the effect of peptic-tryptic digest of gliadin (Pt-G) and gliadin (G) on inducible nitric oxide synthase (iNOS) protein expression in RAW 264.7 macrophages stimulated with interferon-gamma (IFN-gamma). Pt-G and G enhanced in a concentration and time-dependent manner NO production by IFN-gamma-stimulated RAW 264.7 cells. The increase of iNOS protein expression was correlated with NF-kappa B/DNA binding activity and occurred at transcriptional level. Pyrrolidine dithiocarbamate and N-alpha-para-tosyl-L-lysine chloromethyl ketone, two known inhibitors of NF-kappa B activation, decreased significantly NO production and iNOS protein expression as well as NF-kappa B/DNA binding activity. Our results show that the effect of Pt-G and G on enhancement of iNOS protein expression in IFN-gamma-treated RAW 264.7 cells is mainly mediated through NF-kappa B and suggest that blockage of NF-kappa B activation reduces enhancing effect of gluten on NO production in inflamed mucosa of coeliac patients.
Maiuri
Maria Chiara
MC
Dipartimento di Farmacologia Sperimentale, Facoltà di Scienze Biotecnologiche, Università degli Studi di Napoli Federico II, Via D. Montesano 49, 80131 Naples, Italy.
De Stefano
Daniela
D
Mele
Guido
G
Iovine
Barbara
B
Bevilacqua
Maria Assunta
MA
Greco
Luigi
L
Auricchio
Salvatore
S
Carnuccio
Rosa
R
D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D004586:Electrophoresis; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D015870:Gene Expression; D005903:Gliadin / Q000494:pharmacology*; D007371:Interferon-gamma / Q000378:metabolism* / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000096:biosynthesis* / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000378:metabolism; D011759:Pyrrolidines / Q000494:pharmacology; D013859:Thiocarbamates / Q000494:pharmacology; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology
D004791:Enzyme Inhibitors; D016328:NF-kappa B; D009573:Nitrites; D011759:Pyrrolidines; D013859:Thiocarbamates; D014107:Tosyllysine Chloromethyl Ketone; C020972:pyrrolidine dithiocarbamic acid; D009569:Nitric Oxide; D007371:Interferon-gamma; D005903:Gliadin; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse