Intra-articular injectable hydroxypropyl chitin/hyaluronic acid hydrogel as bio-lubricant to attenuate osteoarthritis progression

Osteoarthritis is a chronic degenerative joint disease and its signs of progress mainly attribute to the significant increase of joint friction and the destruction of articular cartilage. Combined cartilage repair and joint lubrication may be a feasible strategy for the treatment of osteoarthritis. In this study, the hydroxypropyl chitin (HPCH)/hyaluronic acid (HA) hydrogel, prepared by physical mixing of HA and HPCH, was designed to be a new bio-lubricant and a chondroprotective agent for osteoarthritis treatment. HA release in HPCH/HA hydrogel was more durable and stable and in vitro experiments showed that HPCH/HA hydrogel could promote the synthesis of the extracellular matrix of chondrocytes. Additionally, HPCH/HA hydrogel could delay the progression of osteoarthritis in DMM-induced osteoarthritis mouse model. To sum up, HPCH/HA hydrogel developed herein can achieve the dual function of well lubrication of joints and protection of cartilage and has the clinical potential as synergetic treatment of osteoarthritis.