Functional β-TCP/MnO₂ /PCL artificial periosteum promoting osteogenic differentiation of BMSCs by reducing locally reactive oxygen species level.

Abstract

Segmental bone defects caused by trauma, tumor resection or congenital malformations are often reconstructed with autologous, allogeneic bone grafts or artificial bone materials, of which, about 5% ~ 10% will have delayed healing or even nonunion of fractures. The loss of periosteum and excessive accumulation of ROS in fracture site leads to the aging of osteoblasts and the decline of their proliferation and differentiation, thus affecting the fracture healing process. In this study, we prepared a functional modified artificial periosteum β-TCP/MnO₂ /PCL(β-TMP) by electrospinning with a function of catalyzing decomposition of H₂ O₂ . We examined the surface morphology of β-TMP, the concentration of Ca, P and Mn of β-TMP, as well as the diameter distribution range of nanofibers on β-TMP. Through X-ray diffraction patterns and Fourier transform infrared spectra, β-TMP was characterized and its hydrophilicity was tested. The release of Mn²⁺ and Ca²⁺ of 0.1 and 0.05% β-TMP in different pH values (7.4 and 5.5) determined by ICP. We also identified that β-TMP could reduce the level of ROS in cells by lowering the level of H₂ O₂ . 0%, 0.05% and 0.1% β-TMP displayed good cell compatibility, cell adhesion and cellular morphology in the condition with or without H₂ O₂ . 0.5% β-TMP showed compromised cell compatibility in normal condition, however, the compromised phenotypes could be partially rescued in the present of H₂ O₂ . Compared with 0%, 0.05% and 0.1% β-TMP displayed higher osteoblastic differentiation with or without H₂ O₂ in BMSCs as well as in MG-63. In sum, β-TMP helped osteogenesis and promoted repair of bone defects.