SIRT2 and osteoporosis: To investigate whether SIRT2 in BMDMs plays a role in osteoporosis, we generated BMDM-specific SIRT2 knockout mice (SIRT2flox/floxLyz2-Cre+, SIRT2-KOlyz) by using Cre driven by Lyz2 (Lysosome C-2) promoters28.