Preparation of cross-linked carboxymethyl chitosan for repairing sciatic nerve injury in rats.
A successful nerve regeneration process was achieved with nerve repair tubes made up of 1-ethyl-3(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) cross-linked carboxymethyl chitosan (CM-chitosan) with improved biodegradability. Chitosan has a very slow degradation rate, while the EDC cross-linked CM-chitosan tubes degraded to 30% of original weight during 8 weeks of incubation in lysozyme solution. In vitro cell culture indicated that the CM-chitosan films presented no cytotoxicity to Schwann cells. From in vivo studies using a 10 mm rat sciatic nerve defect model investigated by histomorphometry analysis, the average diameter of the fibers and the average thickness of myelin sheath in the CM-chitosan tubes were 3.7 +/- 0.33 and 0.33 +/- 0.04 mum, respectively, which demonstrated equivalence to nerve autografts (the current "gold" standard); furthermore, the average fiber density in the CM-chitosan tubes was 20.5 x 10(3)/mm(2), which was similar to that of autografts (21 x 10(3)/mm(2)) and significantly higher than that of common chitosan tubes (15.3 x 10(3)/mm(2)).
Wang
Gan
G
Department of Biological Sciences and Biotechnology, State Key Lab of Biomembrane and Membrane Biotechnology, Tsinghua University, 100084, Beijing, China.
Lu
Guangyuan
G
Ao
Qiang
Q
Gong
Yandao
Y
Zhang
Xiufang
X
D020341:Absorbable Implants; D000818:Animals; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry / Q000627:therapeutic use; D005260:Female; D048091:Guided Tissue Regeneration / Q000379:methods*; D008853:Microscopy; D009416:Nerve Regeneration / Q000502:physiology*; D019635:Neurosurgical Procedures / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000166:cytology; D012584:Sciatic Nerve / Q000293:injuries* / Q000601:surgery*
C514968:carboxymethyl-chitosan; D048271:Chitosan