SIRT6 and osteoporosis: Sugatani et al.20, 21, 22 obtained similar results with SIRT6-KO BMSCs, which may be explained by the increased expression of Runx2 in osteoblasts.20, 21, 22 In all, SIRT6 defects further support the idea that SIRT6 leads to low calcification and exacerbates senile osteoporosis to some degree.