Targeting miR-337 mitigates disuse-induced bone loss.
Uncover the hidden culprit behind disuse-induced bone loss - microRNA-337. This key finding reveals a promising therapeutic strategy to combat the debilitating effects of long-term bed rest and spaceflight on our skeletal health.
This study used a rodent model of hindlimb unloading to investigate the mechanisms underlying disuse-induced bone loss. The researchers found that decreased numbers of leptin receptor-positive mesenchymal stem cells in the bone marrow contributed to this condition. Upregulation of microRNA-337 in these cells inhibited their proliferation by targeting the IRS-1/PI3K/Akt/mTOR pathway. Remarkably, knocking out microRNA-337 significantly mitigated disuse-induced, but not ovariectomy-induced, bone loss. Transplanting microRNA-337-deficient mesenchymal stem cells into wild-type mice under hindlimb unloading was sufficient to prevent bone loss. These findings provide valuable insights into the cellular and molecular mechanisms underlying disuse-induced bone loss and offer a promising therapeutic strategy to address this debilitating condition on Earth and during spaceflight.