Chitosan tubes of varying degrees of acetylation for bridging peripheral nerve defects.
Biosynthetic nerve grafts are desired as alternative to autologous nerve grafts in peripheral nerve reconstruction. Artificial nerve conduits still have their limitations and are not widely accepted in the clinical setting. Here we report an analysis of fine-tuned chitosan tubes used to reconstruct 10 mm nerve defects in the adult rat. The chitosan tubes displayed low, medium and high degrees of acetylation (DAI: ≈ 2%, DA: ≈ 5%, DAIII: ≈ 20%) and therefore different degradability and microenvironments for the regenerating nerve tissue. Short and long term investigations were performed demonstrating that the chitosan tubes allowed functional and morphological nerve regeneration similar to autologous nerve grafts. Irrespective of the DA growth factor regulation demonstrated to be the same as in controls. Analyses of stereological parameters as well as the immunological tissue response at the implantation site and in the regenerated nerves, revealed that DAI and DAIII chitosan tubes displayed some limitations in the support of axonal regeneration and a high speed of degradation accompanied with low mechanical stability, respectively. The chitosan tubes combine several pre-requisites for a clinical acceptance and DAII chitosan tubes have to be judged as the most supportive for peripheral nerve regeneration.
Institute of Neuroanatomy, Hannover Medical School, Hannover, Germany; Center for Systems Neuroscience (ZSN), Hannover, Germany.
Kirsten
K
Haastert-Talini
Stefano
S
Geuna
Lars B
LB
Dahlin
Cora
C
Meyer
Lena
L
Stenberg
Thomas
T
Freier
Claudia
C
Heimann
Christina
C
Barwig
Luis F V
LF
Pinto
Stefania
S
Raimondo
Giovanna
G
Gambarotta
Silvina Ribeiro
SR
Samy
Nuno
N
Sousa
Antonio J
AJ
Salgado
Andreas
A
Ratzka
Sandra
S
Wrobel
Claudia
C
Grothe
D000107:Acetylation; D000818:Animals; D015153:Blotting, Western; D048271:Chitosan / Q000737:chemistry*; D002850:Chromatography, Gel; D004594:Electrophysiology; D005260:Female; D048091:Guided Tissue Regeneration / Q000379:methods; D007150:Immunohistochemistry; D009682:Magnetic Resonance Spectroscopy; D009416:Nerve Regeneration / Q000502:physiology; D010525:Peripheral Nerves / Q000473:pathology / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
D048271:Chitosan
Chitosan; Connective tissue; Degradation; Electrophysiology; Histomorphometry; Nerve guide