Osteogenic effect of self-assembled amelogenin-inspired oligopeptide amphiphile on rat bone defect
Objective:To investigate the reparative effect of self-assembled amelogenin-inspired oligopeptide amphiphile on bone defects.Methods:We prepared self-assembled amelogenin-inspired oligopeptide amphiphile nanogel with adhesive properties and bone marrow stromal cells(BMSCs)cell sheets,and constructed a rat femoral bone defect model.SD rats were randomly divided into four groups,blank control group(Control),BMSCs cell sheet group(Cell Sheet),amelogenin-inspired oligopeptide amphiphile scaffold group(OPA Scaffold),and BMSCs cell sheet plus amelogenin-inspired oligopeptide amphiphile scaffold group(Cell Sheet/OPA Scaffold).The femoral bone defects were filled with these materials,and the reparative effect was evaluated through gross observation,Micro-CT scanning and histopathological examination at week 8 after surgery.Results:Postoperative gross observation showed that varying degrees of bone repair occurred in all groups.The cell sheet group still had a clear outline of the defect area and the area was still deep,resulting in the worst bone repair.The other two groups exhibited better bone repair than the control group,and the cell sheet/OPA scaffold group had the best bone repair,and the defect area was no longer obvious.Micro-CT 3D reconstruction and quantitative analysis showed that the new bone formation rate in the cell sheet group was lower than that in the control group(P<O.05).The rates in the OPA scaffold group and the cell sheet/OPA scaffold group were higher than that in the control group(P<0.05),and both groups had higher trabeculae number,trabecular thickness,bone volume/total volume and connective density(Tb.N,Tb.Th,BV/TV and Conn.D)and lower trabecular spacing(Tb.Sp)in the defect area,with the cell sheet/OPA scaffold group having highest values.Histopathological examination showed that the OPA scaffold group and cell sheet/OPA scaffold group had more mature bone trabecular formation,while the control group and cell sheet group had fewer.Conclusion:Self-assembled amelogenin-inspired oligopeptide amphiphile nanogel has good osteogenic ability and bone defect repair ability,so it has the potential to be used as a scaffold material for further exploration in bone tissue engineering.