Biological performance of a novel biodegradable polyamidoamine hydrogel as guide for peripheral nerve regeneration

Department of Endocrinology, Pathophysiology, and Applied Biology, Università degli Studi di Milano, Via G. Balzaretti 9, 20133 Milan, Italy.
Journal of Biomedical Materials Research Part A (Impact Factor: 2.83). 07/2011; 98(1):19-30. DOI: 10.1002/jbm.a.33091
Source: PubMed

ABSTRACT Polyamidoamines (PAAs) are a well-known family of synthetic biocompatible and biodegradable polymers, which can be prepared as soft hydrogels characterized by low interfacial tension and tunable elasticity. For the first time we report here on the in vivo performance of a PAA hydrogel implant as scaffold for tissue engineering. In particular, an amphoteric agmatine-deriving PAA hydrogel shaped as small tubing was obtained by radical polymerization of a soluble functional oligomeric precursor and used as conduit for nerve regeneration in a rat sciatic nerve cut model. The animals were analyzed at 30, 90, and 180 days post-surgery. PAA tubing proved to facilitate nerve regeneration. Good surgical outcomes were achieved with no signs of inflammation or neuroma. Moreover, nerve regeneration was morphologically sound and the quality of functional recovery satisfactory. In conclusion, PAA hydrogel scaffolds may represent a novel and promising material for peripheral nerve regeneration.

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