title: Curcumin upregulates S100 expression and improves regeneration of the sciatic nerve following its complete amputation in mice.
abstract: The repair of peripheral nerve injury after complete amputation is difficult, and even with anastomosis, the rapid recovery of nerve function remains challenging. Curcumin, extracted from plants of the genus Curcuma, has been shown to have anti-oxidant and anti-inflammatory properties and to improve sciatic nerve crush injury in rats. Here, we determined whether curcumin had neuroprotective effects following complete peripheral nerve amputation injury. BALB/c mice underwent complete sciatic nerve amputation, followed by an immediate epineurium anastomosis. Mice were intragastrically administered curcumin at doses of 40 (high), 20 (moderate), and 10 mg/kg/d (low) for 1 week. We found that myelin in the mice of the high- and moderate-dose curcumin groups appeared with regular shape, uniform thickness, clear boundary, and little hyperplasia surrounding the myelin. High and moderate doses of curcumin markedly improved both action potential amplitude of the sciatic nerves and the conduction velocity of the corresponding motor neurons, and upregulated mRNA and protein expression of S100, a marker for Schwann cell proliferation, in L4-6 spinal cord segments. These results suggest that curcumin is effective in promoting the repair of complete sciatic nerve amputation injury and that the underlying mechanism may be associated with upregulation of S100 expression.
authors.affiliation: Department of Orthopedics, the Second Hospital of Jilin University, Changchun, Jilin Province, China.
authors.forename: Guo-Min
authors.initials: GM
authors.lastname: Liu
authors.affiliation: Department of Health Laboratory, School of Public Health, Jilin University, Changchun, Jilin Province, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Xu
authors.affiliation: Department of Health Laboratory, School of Public Health, Jilin University, Changchun, Jilin Province, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Stomatology, the Second Hospital of Jilin University, Changchun, Jilin Province, China.
authors.forename: Yun-Gang
authors.identifier: 0000-0002-5075-2759
authors.initials: YG
authors.lastname: Luo
keywords: complete nerve amputation; electrophysiology; epineurium anatomosis; myelin sheath; myelinated fiber; nerve regeneration; neural regeneration; spinal cord