Biphasic effect of IL-1beta on the activity of argininosuccinate synthetase in Caco-2 cells. Involvement of nitric oxide production.
The expression of the argininosuccinate synthetase gene (ASS), the limiting enzyme of arginine synthesis, was previously shown to be rapidly induced by a short-term (4 h) exposure to IL-1beta in Caco-2 cells [Biochimie, 2005, 403-409]. The present report shows that, by contrast, a long-term (24 h) exposure to IL-1beta inhibited the ASS activity despite an increase in both specific mRNA level and protein amount, demonstrating a post-translational effect. Concerning the mechanism involved, we demonstrate that the inhibiting effect is linked to the production of nitric oxide (NO) induced by IL-1beta. Indeed, the inhibiting effect of IL-1beta was totally blocked in the presence of l-NMMA, an inhibitor of the inducible nitric oxide synthase, or by culturing the cells in an arginine-deprived medium. Moreover, a decrease in the ASS activity was induced by culturing the cells in the presence of SNAP, a NO donor. Conversely, blocking the action of NO by antioxidant agents, the stimulatory effect of IL-1beta on ASS activity was restored, as measured at 24 h. Finally, such an inhibiting effect of NO on ASS activity may be related, at least in part, to S-nitrosylation of the protein. The physiological relevance of the antagonistic effects of IL-1beta and NO on ASS is discussed.
Brasse-Lagnel
Carole
C
Groupe Appareil Digestif, Environnement et Nutrition, Institut Fédératif de Recherches Multidisciplinaires sur les Peptides, Faculté de Médecine-Pharmacie de Rouen, 22, boulevard Gambetta, 76183 Rouen cedex, Université de Rouen, France.
Lavoinne
Alain
A
Fairand
Alain
A
Vavasseur
Karine
K
Deniel
Nicolas
N
Husson
Annie
A
D001120:Arginine / Q000172:deficiency; D001124:Argininosuccinate Synthase / Q000378:metabolism*; D018938:Caco-2 Cells; D006801:Humans; D053583:Interleukin-1beta / Q000494:pharmacology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D019323:omega-N-Methylarginine / Q000378:metabolism
D053583:Interleukin-1beta; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D001120:Arginine; D052247:Nitric Oxide Synthase Type II; D001124:Argininosuccinate Synthase