(1) Background: The onset of inflammation and oxidative stress after biomaterial implantation can lead to complications and prolonged recovery times. To address this, bioactive mesoporous glasses doped with cerium (0, 3.6 and 5.3 mol%) were loaded with three different biomolecules—3-hydroxyflavone, quercetin and morin hydrate—to enhance antioxidant properties while preserving bioactivity. (2) Methods: Elemental analysis, specific surface area determination, spectroscopic techniques, evaluation of antioxidant activity and in vitro bioactivity assessment were performed to characterize mesoporous glass loaded with biomolecules. (3) Results: Biomolecule loading gives values in the range of 0.5–2.0% and 10.3–39.6% for loading content and loading efficiency, respectively. The loading order is quercetin > morine hydrate > 3-hydroxyflavone, and a cerium percentage of 3.6 seems to be a good compromise. The antioxidant properties evaluated on both solids and solutions in contact with simulated biological fluids improve markedly over loaded glasses, and the most promising results are obtained with quercetin. In the most efficient systems, the bioactivity results were delayed and more evident at longer times (168 h) but were still retained. (4) Conclusions: We obtained new materials still bioactive with improved antioxidant properties that can be proposed for the regeneration of both hard and soft tissues.
Background: Bioactive cerium-doped (Ce-BGs) glasses with proven antioxidant properties, which may reduce post-implant oxidative stress, were studied in vitro and in vivo to evaluate their application in bone regeneration. Based on the Kokubo (K) composition, they contain 3.6 and 5.3 mol% cerium (referred to as K3.6 and K5.3, respectively). Methods: Ce-BGs were synthesized by melting and sieved to produce granules (size range = 200–500 µm). In vitro studies were conducted against MLO-Y4 cells using direct Neutral Red (NR) and indirect Bromo-2-deoxyUridine (BrdU) assays to assess cell viability and proliferation respectively. In vivo studies were carried out using a New Zealand white rabbit model to evaluate bone healing potential. Results and discussion: NR results showed a significant increase in cell viability for Ce-BGs: 77% for K and 79 and 85% for K3.6 and K5.3, after 24 h. After 72 h, cell viability decreased for K to 58% and increased for K3.6 and K5.3 (76% and 116% respectively). Cerium inhibits cell proliferation in BrdU assay as explainable by the increased durability of Ce-BGs. In vivo studies, after 30 and 60 days, revealed a delayed degradation for Ce-BGs that can stimulate the osteo-regeneration without inflammatory or degenerative effects. Moreover, the new bone area (NBA) was higher for Ce-BGs compared to control; after 60 days 32% for K5.3 versus 21% for K. Conclusions: Ce-BGs granules show improved direct cytocompatibility in vitro and enhance the long-term bone remodeling process in vivo, contributing to a more controlled and effective bone healing compared to the K granules. This improved behavior can be linked to the antioxidant and anti-inflammatory properties of cerium, that can assist bone regeneration and reduce implant-associated inflammation, and to their slower dissolution rate that supports the controlled release of ions. These results suggest Ce-BGs as a promising device for therapeutic applications on hard tissues.