SIRT1 and osteoporosis: Other studies have shown that SIRT1 deletion can increase FoxO acetylation and reduce the levels of FoxO and its target gene heme oxygenase 1 (HO-1), while SIRT1 activation can increase the levels of FoxO and HO-1 and reduce ATP production and mitochondrial activity, thereby inhibiting osteoclast generation and playing an anti-osteoporosis role (38).