69 / 2018-06-25 18:32:46

Ionic-doped Bioceramics for Musculoskeletal Tissues Regeneration

Ionic-doping; bioceramics; musculoskeletal tissue; regenerative medicine.

全体主题 > vi. BAMOS (Biomaterials and Additive Manufacturing: Osteochondral Scaffold innovation)

Musculoskeletal disorders (MSD) are a major burden on individuals, health and social care systems. Customized approaches would not significantly benefit patient outcomes and follow-up treatments, and may result in expensive and sometimes irreversible backsets. Nanostructured bioceramics are able to reinforce tissue regeneration due to their excellent osteogenic and angiogenic capacity.1 The incorporation of ionic elements into the nanostructures have shown to play functional roles in the physiological cellular environment and influence bone health, while improving their mechanical properties.2 This study targets to evaluate calcium phosphate-based bioceramics incorporating ionic dopants, as integral parts of nanostructures designed for MSD regeneration. Results showed that ionic-doped bioceramics displayed increased crystallinity, solubility, and mechanical strength in the range of the cancellous bone values (2-12 MPa), due to ion labelling. The scaffolds presented an adequate porosity index (40-75%) and pore size (230-360 µm), favourable for cell proliferation and new tissue formation. The in vitro bioactivity assays showed the formation of apatite crystals globule-like structures on the SF scaffolds and spherulites- like structures on the SF/doped TCP composites. The release profile varied together with ions content showing a preferential release of Zn2+ in comparison to Sr2+. The biological performance of hASCs presented different responses on cell proliferation/differentiation with the incorporation of different metal ions. hASCs were induced to differentiate toward a osteogenic phenotype by culturing onto the ions coated structures as demonstrated by ALP activity and alizarin red staining. Proliferation is stimulated when Zn is incorporated, while Sr and Mn showed greater osteogenic potential. Therefore, several parameters play a crucial role in the performance of ionic-doped bioceramics, for new tissue formation process. Moreover, it is beneficial the incorporation of metals into structures, thus helping a continuous release to support early induction of osteoblast differentiation, and therefore osteogenesis.

References
1. Pina S, Oliveira JM, Reis RL (2015) Natural Polymer/Calcium Phosphates Nanocomposites for Bone Tissue Engineering and Regenerative Medicine: A Review. Adv Materials 27:1143–1169. https://doi.org/ 10.1002/adma.201403354
2. Pina S, Canadas RF, Jiménez G, Perán M, Marchal JA, Reis RL, Oliveira JM (2017) Biofunctional ionic-doped calcium phosphates – silk fibroin composites for bone tissue engineering scaffolding. Cells Tissues Organs 204: 150-163. https://doi.org/10.1159/000469703