title: Effects of Nano-hydroxyapatite/Poly(DL-lactic-co-glycolic acid) Microsphere-Based Composite Scaffolds on Repair of Bone Defects: Evaluating the Role of Nano-hydroxyapatite Content.
abstract: The aim of the current study was to prepare microsphere-based composite scaffolds made of nano-hydroxyapatite (nHA)/poly (DL-lactic-co-glycolic acid) (PLGA) at different ratios and evaluate the effects of nHA on the characteristics of scaffolds for tissue engineering application. First, microsphere-based composite scaffolds made of two ratios of nHA/PLGA (nHA/PLGA = 20/80 and nHA/PLGA = 50/50) were prepared. Then, the effects of nHA on the wettability, mechanical strength, and degradation of scaffolds were investigated. Second, the biocompatibility and osteoinductivity were evaluated and compared by co-culture of scaffolds with bone marrow stromal stem cells (BMSCs). The results showed that the adhesion, proliferation, and osteogenic differentiation of BMSCs with nHA/PLGA (50/50) were better than those with nHA/PLGA (20/80). Finally, we implanted the scaffolds into femur bone defects in a rabbit model, then the capacity of guiding bone regeneration as well as the in vivo degradation were observed by micro-CT and histological examinations. After 4 weeks' implantation, there was no significant difference on the repair of bone defects. However, after 8 and 12 weeks' implantation, the nHA/PLGA (20/80) exhibited better bone formation than nHA/PLGA (50/50). These results suggested that a proper concentration of nHA in the nHA/PLGA composite should be taken into account when the composite scaffolds were prepared, which plays an important role in the biocompatibility, degradation rate and osteoconductivity.
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Shu
authors.initials: S
authors.lastname: He
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Kai-Feng
authors.initials: KF
authors.lastname: Lin
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Yi-Nan
authors.initials: YN
authors.lastname: Zhao
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Long
authors.initials: L
authors.lastname: Bi
authors.affiliation: Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D002478:Cells, Cultured; D017886:Durapatite / Q000737:chemistry*; D005269:Femur / Q000166:cytology / Q000293:injuries / Q000473:pathology / Q000502:physiology; D019344:Lactic Acid / Q000737:chemistry*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D008863:Microspheres; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010012:Osteogenesis; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D017886:Durapatite
keywords: Bone regeneration; Bone tissue engineering; Microsphere-based composite; Nano-hydroxyapatite; Poly(DL-lactic-co-glycolic acid)