Analysis of the Anti-inflammatory Effects of a Delivery System Based on Alginate Hydrogels Enriched with Bioactive Compounds from Marine Sponge Dysidea robusta.

Articular inflammatory processes are common in rheumatoid arthritis, osteoarthritis, and psoriatic arthritis. Standard therapy relies on oral anti-inflammatory drugs, which can cause systemic side effects with prolonged use. This has driven the search for natural alternatives and safer drug delivery systems. Intra-articular hydrogels enriched with bioactive compounds represent a promising approach, providing localized release of therapeutic molecules and reducing adverse effects. This study developed and characterized alginate (ALG)-based hydrogels enriched with bioactive compounds from the marine sponge Dysidea robusta and evaluated their anti-inflammatory potential in vitro. Hydrogels were prepared by dissolving ALG (1.5% and 3% w/v) and cross-linking with CaCO₃. Characterization included mass stability, scanning electron microscopy (SEM), and oscillatory rheology. Biological assays on fibroblasts and chondrocytes measured cytokine expression (IL-6 and TNF-α) by enzyme-linked immunosorbent assay (ELISA). The hydrogels showed initial mass gain followed by controlled degradation and a lamellar porous structure. Rheological analysis revealed tunable gelation and elasticity, while in vitro assays confirmed biocompatibility and a significant reduction of inflammatory markers. These findings indicate that ALG-based hydrogels containing D. robusta bioactives combine desirable physicochemical properties with anti-inflammatory activity, making them promising candidates for targeted drug delivery and tissue engineering.