Particulate beta-tricalcium phosphate and hydroxyapatite doped with silver promote in vitro osteoblast differentiation in MC3T3-E1 cells.

Background: Calcium phosphates including β-tricalcium phosphate (β-TCP) and hydroxyapatite (HAp) have been widely used for bone regeneration application because of their high osteoconductive activities. In addition, various kinds of inorganic ions enhance differentiation, proliferation, and mineralization of osteoblasts. However, information about the effects of silver-doped β-TCP [β-TCP (Ag)] and HAp [HAp (Ag)] particles on osteogenic differentiation is not available yet.

Objective: We focused on the impact of β-TCP (Ag) and HAp (Ag) particles on the osteogenic differentiation of MC3T3-E1 osteoblast precursor cells.

Methods: MC3T3-E1 osteoblast precursor cells were pre-treated by β-TCP (Ag) or HAp (Ag). And then the medium was changed to differentiation medium. Subsequently, osteoblast differentiation-related markers were determined.

Results: We found that treatment with β-TCP (Ag) or HAp (Ag) particles increased alkaline phosphatase activity in MC3T3-E1 cells. Expression of osteoblast differentiation-related genes also increased after treatment with β-TCP (Ag) or HAp (Ag) particles, a response thought to be regulated by zinc finger-containing transcription factor osterix. The ratio of the receptor activator of nuclear factor kappa-B ligand (RANKL) to osteoprotegerin (OPG) was decreased by β-TCP (Ag) and HAp (Ag) particles.

Conclusion: Silver doping of β-TCP and HAp particles is effective for bone regeneration.