Alginate/Hydroxyapatite-Based Nanocomposite Scaffolds for Bone Tissue Engineering Improve Dental Pulp Biomineralization and Differentiation

• Published in: Stem cells international Vol. 2018; no. 2018; pp. 1 - 13
• Main Authors: Cataldi, Amelia, Di Pietro, Roberta, Marsich, Eleonora, Di Nisio, Chiara, Gallorini, Marialucia, Sancilio, Silvia, Schweikl, Helmut
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Publishing Corporation 01.01.2018; Hindawi; John Wiley & Sons, Inc; Hindawi Limited
• Subjects: Alginates; Alginic acid; Biocompatibility; Biodegradability; Biodegradation; Biomarkers; Biomedical materials; Biopolymers; Bone biomaterials; Bone cancer; Bone growth; Bone healing; Bone marrow; Calcium; Calcium ions; Cancer; Cell adhesion & migration; Cell cycle; Collagen; Composite materials; Dental materials; Dental pulp; Dental restorative materials; Deposition; Differentiation (biology); Extracellular matrix; Gelation; Gene expression; Gluconic acid; Hydroxyapatite; Mechanical properties; Mineralization; Nanocomposites; Natural polymers; Osteoconduction; Oxidative stress; Polymers; Regeneration; Regeneration (physiology); Scaffolds; Stem cells; Substitute bone; Surgical implants; Tissue engineering; Tumor cell lines; Viability
• ISSN: 1687-966X; 1687-9678; 1687-9678
• DOI: 10.1155/2018/9643721

Tissue engineering is widely recognized as a promising approach for bone repair and reconstruction. Several attempts have been made to achieve materials that must be compatible, osteoconductive, and osteointegrative and have mechanical strength to provide a structural support. Composite scaffolds consisting in biodegradable natural polymers are very promising constructs. Hydroxyapatite (HAp) can support alginate as inorganic reinforcement and osteoconductive component of alginate/HAp composite scaffolds. Therefore, HAp-strengthened polymer biocomposites offer a solid system to engineer synthetic bone substitutes. In the present work, HAp was incorporated into an alginate solution and internal gelling was induced by addition of slowly acid-hydrolyzing D-gluconic acid delta-lactone for the direct release of calcium ions from HAp. It has been previously demonstrated that alginate-based composites efficiently support adhesion of cancer bone cell lines. Human dental pulp stem cells (DPSCs) identified in human dental pulp are clonogenic cells capable of differentiating in multiple lineage. Thus, this study is aimed at verifying the mineralization and differentiation potential of human DPSCs seeded onto scaffolds based on alginate and nano-hydroxyapatite. For this purpose, gene expression profile of early and late mineralization-related markers, extracellular matrix components, viability parameters, and oxidative stress occurrence were evaluated and analyzed. In summary, our data show that DPSCs express osteogenic differentiation-related markers and promote calcium deposition and biomineralization when growing onto Alg/HAp scaffolds. These findings confirm the use of Alg/HAp scaffolds as feasible composite materials in tissue engineering, being capable of promoting a specific and successful tissue regeneration as well as mineralized matrix deposition and sustaining natural bone regeneration.