Alpha-lipoic acid loaded in chitosan conduit enhances sciatic nerve regeneration in rat

Document Type : Original Article


1 Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran

2 Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Stem Cell & Regenerative Medicine Research Group, Department of Clinical Biochemistry, Mashhad University of Medical Sciences, Mashhad, Iran

3 Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

4 Department of Clinical Sciences, Faculty of Veterinary Medicine, Lorestan University, Khoramabad, Iran


Objective(s): To investigate the effect of topical administration of alpha-lipoic acid into chitosan conduit on peripheral nerve regeneration using a rat sciatic nerve transection model.
Materials and Methods: Forty five Wistar rats were divided into three experimental groups randomly. A 10-mm gap of sciatic nerve was bridged with a chitosan conduit following surgical preparation and anesthesia. In treatment group, the conduit was filled with 30 µl alpha-lipoic acid (10 mg/kg/bw).It was filled with 30 µl phosphate buffered saline solution in control group. In Sham group sciatic nerve was just exposed.
Results: The recovery of nerve function was faster in treatment group than in control, at 4 and 8 weeks after surgery (P-value<0.05). Conduction velocity was better in treatment group than in control group at 4 and 12 weeks (P-value<0.05). Recovery index was higher in treatment group than the control group, 8 weeks after surgery (P-value <0.05). Greater nerve fiber diameter, axon diameter, and myelin sheath thickness were observed in treatment group compared to control group at 8 and 12 weeks after surgery (P-value<0.05). The immunoreactivity of regenerated axons and myelin sheath in treatment group were far more similar to sham group.
Conclusion: Alpha-lipoic acid when loaded in a chitosan conduit could improve transected sciatic nerve regeneration in rat.


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