title: Evaluation of biodegradable polymer conduits--poly(L-lactic acid)--for guiding sciatic nerve regeneration in mice.
abstract: Polymeric biomaterials are often used for stimulating nerve regeneration. Among different conduits, poly(lactide acid) - PLA polymer is considered to be a good substrate due to its biocompatibility and resorbable characteristics. This polymer is an aliphatic polyester which has been mostly used in biomedical application. It is an organic compound with low allergenic potential, low toxicity, high biocompatibility and predictable kinetics of degradation. In this study we fabricated and evaluated a PLA microporous hollow fiber as a conduit for its ability to bridge a nerve gap in a mouse sciatic nerve injury model. The PLA conduit was prepared from a polymer solution, throughout extrusion technique. The left sciatic nerve of C57BL/6 mouse was transected and the nerve stumps were placed into a resorbable PLA (PLA group) or a PCL conduit (PCL group), n=5 each group. We have also used another group in which the nerves were repaired by autograft (autograft group, n=5). Motor function was analyzed according to sciatic functional index (SFI). After 56days, the regenerated nerves were processed for light and electron microscopy and morphometric analyses were performed. A quantitative analysis of regenerated nerves showed significant increase in the number of myelinated fibers and blood vessels in animals that received PLA conduit. The PLA group exhibited better overall tissue organization compared to other groups. Presenting well-organized bundles, many regenerating clusters composed of preserved nerve fibers surrounded by layers of compacted perineurium-like cells. Also the SFI revealed a significant improvement in functional recovery. This work suggests that PLA conduits are suitable substrate for cell survival and it provides an effective strategy to be used to support axonal growth becoming a potential alternative to autograft.
authors.affiliation: Pós Graduação em Anatomia Patológica, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil; Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Camila Oliveira
authors.initials: CO
authors.lastname: Goulart
authors.affiliation: Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Fátima Rosalina Pereira
authors.initials: FR
authors.lastname: Lopes
authors.affiliation: Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil; Departamento de Morfologia, UFPI, Piauí, PI, Brazil.
authors.forename: Zulmira Oliveira
authors.initials: ZO
authors.lastname: Monte
authors.affiliation: Pós Graduação em Anatomia Patológica, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Severino Valentim
authors.initials: SV
authors.lastname: Dantas
authors.affiliation: Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Allana
authors.initials: A
authors.lastname: Souto
authors.affiliation: Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Júlia Teixeira
authors.initials: JT
authors.lastname: Oliveira
authors.affiliation: Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil; Pólo Universitário Macaé, UFRJ, Macaé, RJ, Brazil.
authors.forename: Fernanda Martins
authors.initials: FM
authors.lastname: Almeida
authors.affiliation: Department of Mechanics, Politecnico di Torino, Turin, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Tonda-Turo
authors.affiliation: Programa de Eng. Química, COPPE, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Cristina Cardoso
authors.initials: CC
authors.lastname: Pereira
authors.affiliation: Programa de Eng. Química, COPPE, UFRJ, Rio de Janeiro, RJ, Brazil.
authors.forename: Cristiano Piacsek
authors.initials: CP
authors.lastname: Borges
authors.affiliation: Pós Graduação em Anatomia Patológica, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil; Laboratório de Neurodegeneração e Reparo, Faculdade de Medicina, HUCFF, UFRJ, Rio de Janeiro, RJ, Brazil. Electronic address: martinez@histo.ufrj.br.
authors.forename: Ana Maria Blanco
authors.initials: AM
authors.lastname: Martinez
mesh_terms: D000818:Animals; D002470:Cell Survival; D002478:Cells, Cultured; D005069:Evaluation Studies as Topic; D020007:Implants, Experimental; D008297:Male; D008810:Mice, Inbred C57BL; D009416:Nerve Regeneration; D059348:Peripheral Nerve Injuries / Q000628:therapy; D011091:Polyesters / Q000737:chemistry*; D020127:Recovery of Function; D012583:Schwann Cells / Q000502:physiology / Q000648:ultrastructure; D012584:Sciatic Nerve / Q000503:physiopathology*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C033616:poly(lactide)
keywords: Ischiatic nerve; Mice; Nerve conduits; Nerve regeneration; Poly(l-lactic acid)