title: Ectopic osteogenesis and scaffold biodegradation of nano-hydroxyapatite-chitosan in a rat model.
abstract: The bone-formation and scaffold-biodegradation processes have not been fully characterized. This study aimed to determine the osteogenic ability of nHA-CS osteo-induced bone marrow mesenchymal stem cell (BMSC) composites and to explore the relationship between bone formation and scaffold biodegradation. The nHA-CS osteo-induced BMSC composites (nHA-CS+cells group) and the nHA-CS scaffolds (nHA-CS group) were implanted into the femoral spatium intermusculare of SD rats. At 2, 4, 6, 8, and 12 weeks post-implantation, the rat femurs were scanned using computerized tomography (CT), and the CT values of the implants were measured and comparatively analyzed. The implants were then harvested and subjected to hematoxylin and eosin (HE) and Masson's trichrome staining, and the percentages of bone area, scaffold area and collagen area were compared between the two groups. The CT values of the implants were higher in the nHA-CS+cells group than the nHA-CS group at the same time points (P < 0.05). Histological analysis revealed that de novo bone and collagen formation in the pores of the scaffolds gradually increased from 2 weeks post-implantation in both groups and that the scaffold gradually degraded as bone formation proceeded. However, more de novo bone and collagen formation and scaffold degradation occurred in the nHA-CS+cells group than in the nHA-CS group at the same time points (P < 0.05). In conclusion, nHA-CS osteo-induced BMSC composites are promising bone tissue engineering substitutes, and osteo-induced BMSCs can significantly enhance the osteogenic ability and play an active role in the degradation of nHA-CS scaffolds on par with bone formation.
authors.affiliation: The Orthopaedic Department of The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: He
authors.affiliation: The Orthopaedic Department of The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.
authors.forename: Youhai
authors.initials: Y
authors.lastname: Dong
authors.affiliation: State Key Laboratory of New Ceramic and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing, China.
authors.forename: Fuzhai
authors.initials: F
authors.lastname: Cui
authors.affiliation: The Orthopaedic Department of The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.
authors.forename: Xujun
authors.initials: X
authors.lastname: Chen
authors.affiliation: The Orthopaedic Department of The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.
authors.forename: Rongqiang
authors.initials: R
authors.lastname: Lin
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D001861:Bone Regeneration / Q000187:drug effects*; D018786:Bone Substitutes / Q000737:chemistry / Q000494:pharmacology; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology*; D003094:Collagen / Q000096:biosynthesis; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology*; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects / Q000293:injuries; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000187:drug effects; D053761:Nanocomposites / Q000737:chemistry / Q000627:therapeutic use; D009999:Ossification, Heterotopic / Q000139:chemically induced* / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D014057:Tomography, X-Ray Computed
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D003094:Collagen; D048271:Chitosan; D017886:Durapatite