Dexamethasone-loaded PLGA porous microspheres used as 3D-bioprinted bioink promote tissue-engineered cartilage regeneration

The current investigation focused on fabricating and thoroughly analyzing porous microspheres (MPs) comprising poly (lactic-co-glycolic acid, PLGA) encapsulating dexamethasone, by utilizing the water-in-oil-in-water (W/O/W) emulsion solvent evaporation technique. The meticulous characterization encompassed various parameters, including particle size distribution, morphology, and polymer integrity, all of which exhibited consistent attributes across the MPs populations. The analysis of drug content and release kinetics revealed a sustained and controlled liberation of dexamethasone, characterized by an initial burst release within the initial 3 days followed by a gradual, protracted release profile. Subsequent in vivo assessments further validated the potent anti-inflammatory effects of the dexamethasone-loaded PLGA MPs, as evidenced by notable reductions in CD86 immunohistochemical staining intensity, along with the change in membrane thickness. Additionally, the MPs demonstrated an impressive capability to support the maintenance of cartilage phenotype, as indicated by the augmented secretion of cartilage matrix components and elevated glycosaminoglycan content.