title: Evaluation of nanostructure and microstructure of bone regenerated by BMP-2-porous scaffolds.
abstract: In this study, three systems containing BMP-2 were fabricated, including two electrospun sandwich-like-systems of PLGA 75:25 and PLGA 50:50 and a microsphere system of PLGA 50:50 to be implanted in a critical size defect in rat calvaria. The in vivo BMP-2 release profiles of the three systems were similar. The total dose was released during the first two weeks. To evaluate the nano and microstructure of the regenerated bone a multi-technique analysis was used, including stereo microscope, X-Ray; AFM, micro-CT, and histological analyses. The progression of bone regeneration was followed at 4, 8, and 12 weeks after the microsphere system implantation whereas the two electrospun systems were evaluated at fixed 12 weeks. All the techniques applied showed high bone regeneration. The average values of bone volume density, bone mineral density, Young's modulus, and the percent of bone repair were ∼70% of the values of the native bone. Besides, SEM-EDX analysis indicated that the main chemical elements in the new bone were oxygen, calcium, and phosphorus in a ratio similar to that of native bone. In comparison, the micro-CT may provide an alternative to histology for the evaluation of bone formation at the defect size.
authors.affiliation: Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38200, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Del Rosario
authors.affiliation: Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38200, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Rodríguez-Evora
authors.affiliation: Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38200, Spain.|Institute of Biomedical Technologies (ITB), Center for Biomedical Research of the Canary Islands, University of La Laguna, 38200, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Reyes
authors.affiliation: Department of Physico-Chemistry, Institute of Materials and Nanotechnology, University of La Laguna, 38200, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: González-Orive
authors.affiliation: Department of Physico-Chemistry, Institute of Materials and Nanotechnology, University of La Laguna, 38200, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Hernández-Creus
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling (STEM), School of Pharmacy, University of Nottingham, United Kingdom.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Shakesheff
authors.affiliation: Wolfson Centre for Stem Cells, Tissue Engineering and Modelling (STEM), School of Pharmacy, University of Nottingham, United Kingdom.
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: White
authors.affiliation: Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38200, Spain.|Institute of Biomedical Technologies (ITB), Center for Biomedical Research of the Canary Islands, University of La Laguna, 38200, Spain.
authors.forename: Araceli
authors.initials: A
authors.lastname: Delgado
authors.affiliation: Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38200, Spain.|Institute of Biomedical Technologies (ITB), Center for Biomedical Research of the Canary Islands, University of La Laguna, 38200, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Evora
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001861:Bone Regeneration / Q000187:drug effects*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D008297:Male; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016062:Porosity; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000493:pharmacokinetics; D012886:Skull / Q000187:drug effects / Q000293:injuries / Q000473:pathology; D054457:Tissue Scaffolds / Q000737:chemistry*; D055114:X-Ray Microtomography
chemical_list: C525718:BMP2 protein, human; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D011994:Recombinant Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid
keywords: AFM; BMP-2; bone regeneration; electrospinning; microspheres; multitechnique analysis