Hydrogen-rich saline promotes motor functional recovery following peripheral nerve autografting in rats.

Despite the application of nerve grafts and considerable microsurgical innovations, the functional recovery across a long peripheral nerve gap is generally partial and unsatisfactory. Thus, additional strategies are required to improve nerve regeneration across long nerve gaps. Hydrogen possesses antioxidant and anti-apoptotic properties, which could be neuroprotective in the treatment of peripheral nerve injury; however, such a possibility has not been experimentally tested in vivo. The aim of the present study was to investigate the effectiveness of hydrogen-rich saline in promoting nerve regeneration after 10-mm sciatic nerve autografting in rats. The rats were randomly divided into two groups and intraperitoneally administered a daily regimen of 5 ml/kg hydrogen-rich or normal saline. Axonal regeneration and functional recovery were assessed through a combination of behavioral analyses, electrophysiological evaluations, Fluoro-Gold™ retrograde tracings and histomorphological observations. The data showed that rats receiving hydrogen-rich saline achieved better axonal regeneration and functional recovery than those receiving normal saline. These findings indicated that hydrogen-rich saline promotes nerve regeneration across long gaps, suggesting that hydrogen-rich saline could be used as a neuroprotective agent for peripheral nerve injury therapy.

Triptolide improves nerve regeneration and functional recovery following crush injury to rat sciatic nerve.

Recently, accumulating data have demonstrated that triptolide exhibits neurotrophic and neuroprotective properties. However, the role of triptolide in repair and regeneration of peripheral nerve injury (PNI) has rarely been performed. The current study was designed to observe the possible beneficial effect of triptolide on promoting peripheral nerve regeneration in rats. Rats with sciatic nerve crush injury were administered daily with triptolide for 7 days. Axonal regeneration was evaluated by morphometric analysis and Fluoro-gold retrograde tracing. Motor functional recovery was evaluated by walking track analysis, electrophysiological assessment and histological appearance of target muscles. Levels of pro-inflammatory cytokines within injured nerves were also determined. The results demonstrated that triptolide was capable of promoting peripheral nerve regeneration. Additionally, triptolide significantly decreased the levels of pro-inflammatory cytokines within injured nerves. These findings indicate the possibility of developing triptolide as a therapeutic agent for PNI. The neuroprotective effects of triptolide might be associated with its anti-inflammatory properties.

Schwann cell-seeded scaffold with longitudinally oriented micro-channels for reconstruction of sciatic nerve in rats.

To provide a more permissive environment for axonal regeneration, Schwann cells (SCs) were introduced into a collagen-chitosan scaffold with longitudinally oriented micro-channels (L-CCH). The SC-seeded scaffold was then used for reconstruction of a 15-mm-long sciatic nerve defect in rats. The axonal regeneration and functional recovery were examined by a combination of walking track analysis, electrophysiological assessment, Fluoro-Gold retrograde tracing, as well as morphometric analyses to both regenerated axons and target muscles. The findings showed that SCs adhered and migrated into the L-CCH scaffold and displayed a longitudinal arrangement in vitro. Axonal regeneration as well as functional recovery was in the similar range between SCs-seeded scaffold and autograft groups, which were superior to those in L-CCH scaffold alone group. These indicate that the SCs-seeded L-CCH scaffold, which resembles the microstructure as well as the permissive environment of native peripheral nerves, holds great promise in nerve regeneration therapies.

Salidroside promotes peripheral nerve regeneration following crush injury to the sciatic nerve in rats.

Salidroside (SDS), a phenylpropanoid glycoside isolated from Rhodiola rosea L., has been reported to be neuroprotective in vitro, which raises the possibility of using SDS as a neuroprotective agent after nerve injuries. In the present study, the possibly beneficial effect of SDS on promoting nerve regeneration after sciatic nerve crush injury in rats was investigated. Rats with sciatic nerve crush injury were administered intraperitoneally daily with 5 or 10 mg/kg body weight of SDS for 4 weeks. Rats that received mecobalamin or saline were considered as a positive or a negative control, respectively. Morphometric analysis of regenerated nerves and Fluoro-Gold retrograde tracing was used to evaluate axonal regeneration, whereas walking track analysis, electrophysiological assessment, and histological appearance of target muscles were carried out to evaluate the recovery of motor function. The results showed that SDS achieved functionally successful nerve regeneration in the rat sciatic nerve crush injury model, indicating that SDS holds potential as a neuroprotective agent for peripheral nerve therapies.

Omentum-wrapped scaffold with longitudinally oriented micro-channels promotes axonal regeneration and motor functional recovery in rats.

BACKGROUND: Tissue-engineered nerve scaffolds hold great potential in bridging large peripheral nerve defects. However, insufficient vascularization of nerve scaffolds limited neural tissues survival and regeneration, which hampered the successful implantation and clinical application of nerve scaffolds. The omentum possesses a high vascularization capacity and enhances regeneration and maturation of tissues and constructs to which it is applied. However, combined application of nerve scaffolds and omentum on axonal regeneration and functional recovery in the treatment of large peripheral nerve defects has rarely been investigated thus far. METHODS: In the present study, an omentum-wrapped collagen-chitosan scaffold was used to bridge a 15-mm-long sciatic nerve defect in rats. Rats that received nerve autografts or scaffolds alone were served as positive control or negative control, respectively. The axonal regeneration and functional recovery were examined by a combination of walking track analysis, electrophysiological assessment, Fluoro-Gold (FG) retrograde tracing, as well as morphometric analyses to both regenerated nerves and target muscles. FINDINGS: The results demonstrated that axonal regeneration and functional recovery were in the similar range between the omentum-wrapping group and the autograft group, which were significantly better than those in the scaffold alone group. Further investigation showed that the protein levels of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were significantly higher in the omentum-wrapping group than those in the scaffold alone group in the early weeks after surgery. CONCLUSION: These findings indicate that the omentum-wrapped scaffold is capable of enhancing axonal regeneration and functional recovery, which might be served as a potent alternative to nerve autografts. The beneficial effect of omentum-wrapping on nerve regeneration might be related with the proteins produced by omentum.