SIRT1 and osteoporosis: As miR-217 has been shown to sponge different circRNAs, such as circ-VANGL1 and promote osteoporosis development by downregulating RUNX2 expression, or circRNA_100367 [52,53] it would be interesting that future studies explore circRNAs/miR-217 interactions and SIRT1 regulation in OA chondrocytes.