In addition, SIRT2 was reported to be positively associated with NAMPT actions in human gingival fibroblasts, which was highly upregulated during periodontitis and engaged in osteoclast recruitment, inducing the expression of COX-2, matrix metalloproteinase (MMP)-1 and MMP-3 (Park et al., 2017; Hassan et al., 2018). This evidence concerns the gene SIRT2 and periodontitis.