Suppression of anoikis by collagen coating of interconnected macroporous nanometric carbonated hydroxyapatite/agarose scaffolds

Abstract

Three dimensional interconnected macroporous (pore diameter: 600-800 μm) hydroxyapatite/agarose disks have been evaluated in this study as potential bone regeneration scaffolds. With this purpose, the adhesion and proliferation of human Saos-2 osteoblasts on this biomaterial were analyzed. As an index of cell function, the following parameters were measured: cell morphology, viability, cell size/complexity, cell cycle, reactive oxygen species (ROS) content, and lactate dehydrogenase (LDH) release. The existence of anoikis induced by inappropriate contacts between the cell and the scaffold has been detected by scanning electron microscopy, confocal microscopy, and flow cytometry. The intracellular nitric oxide content has been also measured as potential inducer of anoikis. The positive effects of previous scaffold coating with type I collagen on osteoblast adhesion as well as the collagen protection against anoikis have been demonstrated in this study.

Control of the pore architecture in three-dimensional hydroxyapatite-reinforced hydrogel scaffolds

“…Other shaping methods of the nanocrystalline carbonated hydroxyapatite may reduce its high surface area (120 m 2 g −1 ), increase the crystal size and dissolve it. This would decrease its reactivity and thus osteogenic capacity, thereby affecting the bioactivity of this apatite when implanted in living organisms [63]. Table 1 lists the compositions of the slurries used to prepare the scaffolds, demonstrating the versatility of the GELPOR3D technique.…”

On the synthesis and characterization of β-tricalcium phosphate scaffolds coated with collagen or poly (D, L-lactic acid) for alveolar bone augmentation

“…[ 5 7 8 10 11 13 18 ] Several ceramic materials composed of Ca/P have been used in bone reparation with predictable results. [ 5 6 19 23 24 25 26 27 ] Apatite-like ceramics such as β-TCP are commercially available due to its excellent osteoconductivity and biodegradability. The pursuit of a biodegradable synthetic bone substitute has led clinicians and the scientific community to look on the ceramic scaffolds as a feasible possibility.…”

Response of osteoblasts and preosteoblasts to calcium deficient and Si substituted hydroxyapatites treated at different temperatures

“…The absence of oxidative stress suggests that the low apoptosis levels observed in Fig. 3 (Sub G1 fraction) are due to weak contacts between the cell and the support (tissue culture plastic) in the presence of these powdered materials which can trigger a kind of apoptosis defined as anoikis, induced by loss of cell anchorage [35].…”