Modulation of iNOS expression by a nitric oxide-releasing derivative of the natural antioxidant ferulic acid in activated RAW 264.7 macrophages.Eur J Pharmacol. 2006 Feb 17; 532(1-2):162-9.EJ
We have previously reported that NCX 2057, a new chemical entity bearing a nitric oxide (NO)-releasing moiety linked to the natural antioxidant ferulic acid, shows marked anti-inflammatory properties in a model of chronic brain inflammation. We have now studied the effects of NCX 2057 and its metabolic products, ferulic acid and NCX 2059, on inducible nitric oxide synthase (iNOS) expression and function in lipopolysaccharide/interferon-gamma (LPS/IFNgamma)-stimulated RAW 264.7 macrophages. NCX 2057 inhibited iNOS mRNA and protein expression (IC(50)=6.2+/-1.0 microM) without altering iNOS protein degradation rate. NCX 2057 also decreased the levels of LPS/IFNgamma-induced nitrite accumulation (IC(50)=4.3+/-0.7 microM) in RAW 264.7 cells. Conversely, NCX 2059, which does not possess NO-donating properties, was only weakly effective (IC(50) >100 microM) and ferulic acid was inactive. To understand further the mechanisms underlying anti-inflammatory properties we studied the effects of NCX 2057 on selected transcription factors. Unlike ferulic acid, NCX 2057 inhibited LPS-induced translocation/activation of the nuclear factor, NF-kappaB, while other transcription factors, such as, Sp1, NF-IL2A and STAT-1 were not affected. The present data support the concept that NO adds important anti-inflammatory properties to ferulic acid. Thus, NCX 2057 represents a new prototype drug for the treatment of disorders associated with chronic inflammation and oxidative stress.