Physical property and biological activity of bioscaffold containing the extracted native collagen and acemannan on proliferation and growth factor secretion in primary human pulpal cells

Abstract

Dental pulp tissue regeneration is based on tissue engineering concepts using stem cells, scaffolds, and growth factors to regenerate the pulp-dentine complex. Up to now, native collagen is commonly used as a biomaterial scaffold for tissue regeneration due to its biocompatibility, biodegradability, and properties that mimic the natural extracellular matrix (ECM). However, the bioactivity of collagen scaffold on cell growth and differentiation, and regenerative activities such as extracellular matrix formation and growth factor secretion which are important for pulp revascularization and regeneration and accomplishment root formation is still unclear. Many studies elucidated that adding biomolecules into the collagen scaffold enhanced pulp regeneration. Acemannan, β-(1-4)-acetylated polymannose, is a major polysaccharide extracted from aloe vera. Acemannan functions as an immunomodulator and regenerative biomaterial. Therefore, acemannan could be alternative biomolecule for collagen scaffold. In this study, acemannan and native collagen were cold extracted from aloe vera and porcine skin, respectively, and characterized. The acemannan-collagen (AceCol) scaffolds were prepared using freeze-drying method. The physical properties of AceCol scaffold were investigated using FTIR, SEM, contact angle, swelling, and degradation tests. In vitro, biocompatibility, growth factor secretion, osteogenic proteins expression, and mineral deposition were also evaluated. Our results revealed that the AceCol scaffold has higher hydrophilicity and swelling properties rather that of collagen scaffold (p<0.05). Better cell-cell and cell-scaffold adhesions, and dentin extracellular matrix (BSP, OPN, and DSPP) expression were observed in the AceCol scaffold. Only AceCol group show DSPP expression, while the collagen group did not. Significant increasing of cellular proliferation, VEGF and BMP2 expression, and mineral deposition was detected in the AceCol scaffold compared with that of collagen scaffold (p<0.05). In conclusion, the AceCol scaffold has synergistically provided the better physical and biological properties rather than each individual part. AceCol scaffold is a promising material for tissue regeneration.