OBJECTIVE AND DESIGN: Determine the sources of nitric oxide (NO) and evaluate its role in the activation of nuclear Factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) and in the expression of NO synthase II (NOS II), induced by interleukin-1beta (IL-1). MATERIAL OR SUBJECTS: Primary cultures of bovine articular chondrocytes. TREATMENT: The cells were treated with IL-1, 5 ng/ml with or without the NO donor S-nitroso-N-acetylpenicillamine (SNAP), in concentrations ranging from 10 to 300 microM. METHODS: NF-kappaB and AP-1 activation were evaluated by electrophoretic mobility shift assay. Northern blot was used to detect NOS II mRNA levels and western blot to evaluate IkappaB-alpha, NOS I and NOS II protein levels. RESULTS: Under basal conditions, chondrocytes expressed NOS I, which was lost upon IL-I treatment. SNAP inhibited IL-I-induced NF-kappaB activation and NOS II expression. When added alone, SNAP induced AP-1 activation to approximately the same extent as IL-I. CONCLUSIONS: These results suggest that, in chondrocytes, NO is a key regulator of the signaling pathways leading from IL-I to NF-kappaB and AP-1 activation and to the expression of genes that are involved in the pathophysiology of arthritic diseases.
OBJECTIVE AND DESIGN: Determine the sources of nitric oxide (NO) and evaluate its role in the activation of nuclear Factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) and in the expression of NO synthase II (NOS II), induced by interleukin-1beta (IL-1). MATERIAL OR SUBJECTS: Primary cultures of bovine articular chondrocytes. TREATMENT: The cells were treated with IL-1, 5 ng/ml with or without the NO donorS-nitroso-N-acetylpenicillamine (SNAP), in concentrations ranging from 10 to 300 microM. METHODS: NF-kappaB and AP-1 activation were evaluated by electrophoretic mobility shift assay. Northern blot was used to detect NOS II mRNA levels and western blot to evaluate IkappaB-alpha, NOS I and NOS II protein levels. RESULTS: Under basal conditions, chondrocytes expressed NOS I, which was lost upon IL-I treatment. SNAP inhibited IL-I-induced NF-kappaB activation and NOS II expression. When added alone, SNAP induced AP-1 activation to approximately the same extent as IL-I. CONCLUSIONS: These results suggest that, in chondrocytes, NO is a key regulator of the signaling pathways leading from IL-I to NF-kappaB and AP-1 activation and to the expression of genes that are involved in the pathophysiology of arthritic diseases.
Authors: Jeriel T R Keeney; Sarah Förster; Rukhsana Sultana; Lawrence D Brewer; Caitlin S Latimer; Jian Cai; Jon B Klein; Nada M Porter; D Allan Butterfield Journal: Free Radic Biol Med Date: 2013-07-18 Impact factor: 7.376
Authors: T T Chowdhury; S Arghandawi; J Brand; O O Akanji; D L Bader; D M Salter; D A Lee Journal: Arthritis Res Ther Date: 2008-03-18 Impact factor: 5.156