Anti-Inflammation and Joint Lubrication Dual Effects of a Novel Hyaluronic Acid/Curcumin Nanomicelle Improve the Efficacy of Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease, which can cause endless suffering to the patients and severely impact their normal lives. To treat RA, the drugs in use have many serious side effects, high cost, or only focus on their anti-inflammatory mechanisms without taking joint lubrication into consideration. Therefore, in this study, we aim to construct a novel anti-RA drug composed of hyaluronic acid/curcumin (HA/Cur) nanomicelle to resolve these problems. Characterizations show that Cur is bound to HA by ester linkages and self-assembles to form a spherical nanomicelle with a diameter of around 164 nm under the main driving of the hydrophilic and hydrophobic forces. The nanomicelle enjoys excellent biocompatibility that effectively promotes the proliferation of chondrocytes. When injected to the RA rats, the nanomicelle significantly lowers the edema degree of the arthritic rats compared to other groups; more critically, a dramatic decrease in friction between the surfaces of cartilage around the joints has been found, which protects the cartilage from the RA-induced damage. Additionally, systematic mechanism investigation indicates that the nanomicelle diminishes the expression of related cytokines and vascular endothelial growth factor, finally leading to the excellent performance. The newfound nanomicelle has a potential for clinical practice of RA therapy, which will contribute significantly to alleviating the pain of patients and improving the quality of life for them.