Modulating systemic anti-inflammatory response mitigates osteoarthritis progression and associated pain after low-dose radiotherapy.

Abstract

Osteoarthritis (OA) is a degenerative joint disease, often accompanied by inflammation. It has reported that low-dose radiotherapy (LDRT) has anti-inflammatory effect for benign pathologies and has been used for clinical treatment of OA in some European regions. However, the underlying molecular mechanisms of LDRT alleviating OA are only poorly understood. Herein, it is verified that LDRT improved the locomotor ability of OA rats, increased the locomotor distance and speed in the in vivo experiments. Moreover, LDRT decreased the degree of cartilage damage, attenuated the synovial inflammation, and promoted macrophage polarization towards M2 type. For the in vitro experiments, LDRT promoted macrophage polarization towards M2-type, which enhanced cell growth and adjusted the inflammatory factors in chondrocyte. Additionally, it is found LDRT could ameliorate OA pain through inhibiting spinal cord inflammation. Take together, our study suggests that LDRT could ameliorate OA symptoms and relieve OA-related pain by exerting its anti-inflammatory effect.