Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Effects of NSAIDs and the Cyclooxygenase-Inhibiting Nitric Oxide Donator (CINOD) NCX 429 on Human Chondrocytes and Cartilage from OA Patients.
Bolla1, Manlio, Viappiani2, Serena, Dave4, Mandar, Patel4, Jyoti, Abramson3, Steven B., Attur3, Mukundan
The role of nitric oxide (NO) in osteoarthritis (OA) is controversial. NO, particularly when metabolized to peroxynitrite, is a recognized mediator of inflammation, which induces catabolic effects and promotes chondrocyte apoptosis. Conversely, NO delivered at low concentrations by NO donors exerts anti-inflammatory effects. Cyclooxygenase-Inhibiting Nitric Oxide Donators (CINODs) are anti-inflammatory compounds designed to inhibit both COX-1 and COX-2 while releasing nitric oxide, an important modulator of vascular tone. We studied the effect of naproxen and the CINOD NCX 429 in human chondrocytes and cartilage tissues from OA patients, to understand whether NO donation from CINODs may modulate the inflammatory/metabolic response.
The experiments were performed with human cartilage and chondrocytes isolated from OA cartilage. Isolated chondrocytes stimulated with IL-1b to induce inflammation, followed by measurement of inflammatory and matrix parameters, such as iNOS, COX-2, MMP1 and 13, PGE2, NO, matrix metalloproteinases, collagen degradation and NF-kB nuclear translocation. Reference NSAIDs naproxen and celecoxib were used in comparison to NCX 429 (10 and 50 mM), and incubated 16 h before IL-1b challenge. Cartilage explants culture supernatants (untreated and treated with modulators) were harvested at 24 and 72 hours post-treatment. RNA was extracted from chondrocytes and estimated by qPCR. NF-kB binding was assessed using Marligen Bioscience kit and both cytoplasm and nuclear p65 subunit of NF-kB was also assessed by Western blot.
The reference NSAIDs and the CINOD similarly upregulated MMP1 but inhibited MMP13, showing comparable net effect on collagen degradation as assayed by CTX-II ELISA. They similarly inhibited ADAMTS4, but only 50 mM NCX 429 downregulated COX-2 expression. In isolated OA chondrocytes, NCX 429 (10 and 50 mM) significantly and completely inhibited IL-1b-induced PGE2 production, and both the constitutive and IL-1b-stimulated induction of NF-kB activity. Western blot analysis of p65 subunit isolated from nuclear fraction showed that the cells treated with CINOD (both in unstimulated and IL-1b stimulated cells) had increased p65 accumulation although decreased NF-kB binding and also inhibited NF-kB promoter mediated luciferase reporter assay.
Reference NSAIDs and the CINOD NCX 429 appear to similarly modulate human OA chondrocytes, both in unstimulated and stimulated conditions. NO has been considered detrimental for chondrocytes; however, donation of low concentrations of NO is recognized to be beneficial in a variety of conditions. Here, the CINOD NCX 429 does not differ from reference NSAIDs, indicating that CINODs do not adversely affect chondrocytes via NO donation. In addition, NCX 429 showed inhibition of the NF-kB signalling, therefore presenting interesting anti-inflammatory features to be further explored.
To cite this abstract, please use the following information:
Bolla, Manlio, Viappiani, Serena, Dave, Mandar, Patel, Jyoti, Abramson, Steven B., Attur, Mukundan; Effects of NSAIDs and the Cyclooxygenase-Inhibiting Nitric Oxide Donator (CINOD) NCX 429 on Human Chondrocytes and Cartilage from OA Patients. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :1477