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.

The complicated synthesis procedure and limited preparation size of hydrogel inhibit its clinical application. Therefore, a facile preparation method for large-size hydrogel is required. In this study, a series of curcumin (Cur)/polyvinyl alcohol (PVA) hydrogel in a large size with different Cur concentrations is prepared by a facile physical-chemical crosslinking. The physicochemical properties, antibacterial performance and accelerating wound healing ability are evaluated with the aim of attaining a novel and effective wound dressing. The results show that the as-prepared hydrogel with the optimal Cur to PVA volume ratio of 1:5 (20% Cur/PVA) exhibits the best antibacterial abilities to E. coli (85.6%) and S. aureus (97%) than other hydrogels. When the volume ratio of Cur to PVA is 1:10 (10% Cur/PVA), the hydrogel can significantly accelerate the wound healing in rats, and successfully reconstruct intact and thickened epidermis during 14 day of healing of impaired wounds after histological examination. In one word, the present approach can shed new light on designing new type of hydrogels with promising applications in wound dressing.

No abstract