NAMPT and rheumatoid arthritis: Although Nampt could promote osteogenesis, which may be a target for osteoporosis treatment, it is noticeable that Nampt could act as double-edged swords since its expression is upregulated during inflammation, as NAMPT represents a novel clinical biomarker in acute lung injury [26], rheumatoid arthritis [27], Crohn’s disease [28], and inhibition of Nampt activity attenuates the CLP-induced sepsis in mice [29].