Aging in Articular Chondrocytes and Treatment Strategy for Osteoarthritis by Utilizing Stress Response

Abstract

Osteoarthritis (OA) is a frequent musculoskeletal disorder in the elderly population. OA is characterized by a gradual loss of extracellular matrix in the articular cartilage of joints. No medical agents have shown evidence that they are disease-modifying OA drugs, which attenuates progression of OA, nor has practical application of biological agents that are intended to alleviate symptoms been realized. Therefore, it is preferable to administer conservative therapy that is easy, simple, and effective in inhibiting OA progression at an early stage. Heat shock protein 70 (HSP70) has a protective effect on the cartilage and inhibits the apoptosis of chondrocytes. Hyperthermia to the joints can increase HSP70 expression in chondrocytes, and, at the same time, HSP70 expression partially enhances matrix metabolism of the cartilage. These findings suggest that hyperthermia can be applied to the treatment of OA. Hyperthermia is, therefore, expected to be an inexpensive and less-invasive conservative therapy for OA.