NAMPT Is an Essential Regulator of RA-Mediated Periodontal Inflammation:

Recent studies have indicated a potential correlation between rheumatoid arthritis (RA) and periodontal inflammation. We undertook this study to verify whether RA mediates periodontitis-like phenotypes in experimental mouse models of RA and to explore the role of nicotinamide phosphoribosyltransferase (NAMPT) in periodontal inflammation during RA pathogenesis. Periodontal inflammation and alveolar bone loss have been reported in mice with collagen-induced arthritis (CIA) and in genetically modified tumor necrosis factor–α (TNF-α) transgenic (TG) mouse models. Among the adipokines examined in our study, NAMPT expression was markedly upregulated in the periodontal ligament (PDL) tissues in RA mouse models and in human PDL cells stimulated by the proinflammatory cytokines, interleukin (IL) 1β and TNF-α. When NAMPT was overexpressed with the Nampt-synthesizing adenovirus vector (Ad-Nampt), the PDL cells exhibited an increased expression of cytokines (IL6), chemokines (IL8 and chemokine [C-C motif] ligand 5 [C...