The value of injectable viscoelastic supplements for joints

Locally administered liposomal drug depot enhances rheumatoid arthritis treatment by inhibiting inflammation and promoting cartilage repair

Rheumatoid arthritis (RA) is a chronic autoimmune condition characterized by synovial hyperplasia, where inflammatory macrophages within the joint synovium produce multiple inflammatory cytokines, leading to cartilage damage. The development of therapeutic strategies that combine anti-inflammatory effects and cartilage repair mechanisms holds great promise for effective RA treatment. To address the limitations associated with the off-target effects of intravenous administration and the risk of synovial cavity infection with repeated local injections, we have innovatively developed a liposomal drug depot through hyaluronic acid (HA)-modified liposomes encapsulating dexamethasone sodium phosphate (DSP)-loaded nanogels, termed HA-Lipo@G/D. The nanogels were prepared by ionic cross-linking of chondroitin sulfate and gelatin, both of which have notable cartilage repair properties. In vitro studies demonstrated that this formulation exhibited sustained drug release, enhanced uptake by inflammatory macrophages, reduced secretion of inflammatory factors (TNF-α, IL-1β), and significantly decreased chondrocyte apoptosis induced by inflammatory factors. Moreover, in vivo assessments in a rat model of collagen-induced arthritis revealed effective accumulation of the liposomal drug depot at the inflamed joint site, resulting in macrophage repolarization and cartilage tissue repair. Our findings provide a synergistic strategy for inhibiting inflammation and mitigating cartilage damage through local joint cavity injection, thereby enhancing the therapeutic efficacy of RA.

The Combination of Glucocorticoids and Hyaluronic Acid Enhances Efficacy in IL-1β/IL-17-Treated Bovine Osteochondral Grafts Compared with Individual Application

Patients with knee osteoarthritis often receive glucocorticoid (GC) or hyaluronic acid (HA) injections to alleviate symptoms. This study evaluated the impact of Triamcinolone Hexacetonide (a GC), HA, and a combination of both on bovine osteochondral grafts exposed to IL-1β and IL-17 in an ex vivo culture. Metabolic activity increased with GC treatment. GCs and GCs/HA counteracted cytokine effects, with gene expressions similar to untreated controls, while HA alone did not. However, HA improved the coefficient of friction after two weeks. The highest friction values were observed in GC-containing and cytokine-treated groups. Cytokine treatment reduced tissue proteoglycan content, which HA could mitigate, especially in the GC/HA combination. This combo also effectively controlled proteoglycan release, supported by reduced sGAG release. Cytokine treatment led to surface cell death, while GCs, HA, or their combination showed protective effects against inflammation. The GC/HA combination had the best overall results, suggesting its potential as a superior treatment option for osteoarthritis.

Hyaluronic Acid in Rheumatology

Hyaluronic acid (HA), also known as hyaluronan, is an anionic glycosaminoglycan widely distributed throughout various tissues of the human body. It stands out from other glycosaminoglycans as it lacks sulfation and can attain considerable size: the average human synovial HA molecule weighs about 7 million Dalton (Da), equivalent to roughly 20,000 disaccharide monomers; although some sources report a lower range of 3-4 million Da. In recent years, HA has garnered significant attention in the field of rheumatology due to its involvement in joint lubrication, cartilage maintenance, and modulation of inflammatory and/or immune responses. This review aims to provide a comprehensive overview of HA's involvement in rheumatology, covering its physiology, pharmacology, therapeutic applications, and potential future directions for enhancing patient outcomes. Nevertheless, the use of HA therapy in rheumatology remains controversial with conflicting evidence regarding its efficacy and safety. In conclusion, HA represents a promising therapeutic option to improve joint function and alleviate inflammation and pain.

Deep eutectic solvents-Hydrogels for the topical management of rheumatoid arthritis

Deep eutectic solvents (DES) have demonstrated their ability to facilitate skin penetrability of rigid nanoparticles (NPs). Here, we reported a feasible and simple transdermal delivery strategy using mesoporous silica nanoparticles impregnated in DES hydrogels for topical management of rheumatoid arthritis (RA). To achieve this goal, nanoceria was immobilized within a silica nanoparticle matrix (MSN) and encapsulated with methotrexate (MTX). The functionalized nanoparticles were first engineered in an Arginine (Arg)-citric acid (CA) DES and then transferred to the carbomer hydrogel matrix. Due to the strong affinity of DES hydrogels to the skin, combined with solvent-driven "Drag" effects, the prepared DES-MSNs hydrogels produced dynamic mobility of MSNs through skin layers, resulting in high skin penetrability. After application to the skin, the hydrogel solvent drove the rigid NPs across the skin barrier in a nonintrusive manner, resulting in sustained penetration and accumulation of MSNs at subcutaneous inflammation sites. Subsequently, the MTX payload exerted a direct therapeutic effect, while nanoceria moderated the inflammatory microenvironment by initiating reactive oxygen species (ROS) scavenging and transformation of the macrophage phenotype. In this way, the synergistic action of the combination of immuno- and chemotherapy of the drug and its carrier on RA was achieved. Our work provides a novel strategy for multisite regulation and controlled management of RA in a noninvasive way.