SIRT1 and rheumatoid arthritis: Previous studies demonstrated that Sirt1 overexpression promoted apoptotic resistance and inflammatory secretion in RA-FLSs;25 Sirt1 gene silencing promotes apoptosis of RA-FLSs.29 In contrast, evidence suggests that Sirt1 is important in anti-inflammation through downregulating expression of the cysteine-rich protein 61 in RA-FLSs;30 resveratrol, a Sirt1 activator, induces apoptosis of RA-FLSs.31 Recent studies report that subcellular localization of Sirt1 is associated with cell fate.