Peripheral nerve impairment is a common complication in surgery, clinical researchers always do nerve sutrure using microsurgical technique and adjuvant treatment to improve peripheral nerve regeneration. Western medicine used usually adjuvant drugs, such as neurotrophic factors,are limited by their defects in clinical application. Traditional Chinese medicines (TCMs) classifies peripheral nerve impair as flaccidity Zheng and arthromyodynia, and considers that it is the result of stagnant blood block in the meridians and vessels, deficient of Qi and blood and disuse of bones and muscles. So, drugs usually have the function of invigorating vital energy, activating blood circulation and dredging collaterals. Mono-drugs include astragalus, Salvia miltiorrhiza, Astragali Radix, Epimedii Folium and so on. Extracts of TCMs have Ginkgo Folium, Cervi Cornu Pantotrichum, Achyranthis Bidentatae Radix, and so on. To be ready for further study and development, TCMs which can promote the peripheral nerve regeneration were reviewed by the literatures of the latest years.
Animals ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Nerve Growth Factors ; pharmacology ; Nerve Regeneration ; drug effects ; Peripheral Nerves ; drug effects ; physiology

AIMTo explore the effect of Simvastatin on the regeneration of sciatic nerve with crush injury in rats.

METHODSAnimals were randomized into the following experimental groups: Simvastatin-treated, vehicle and sham-operated groups. Sciatic nerves with crush injury were performed. After surgery, the functional evaluation of nerve recovery, electrophysiologic assessment, histological assessment, serum IL-6 and lipid were performed.

RESULTSThe toe spread index of Simvastatin-treated rats after operation was higher significantly than vehicle rats at 5 d and 8 d (P<0.05). CMAP was higher and NCV was faster (P < 0.05). The serum IL-6 at 5 d of post-operation was significant lower (P < 0.05). Total serum cholesterol of Simvastatin-treated animals was higher than that of other animals (P < 0.05) at 2 weeks of post-operation. The histological analysis showed that the numbers of myelinated axons and the thickness of myelin sheath of Simvastatin-treated crush injury animals at 4 weeks of post-operation were more than that of vehicle animals.

CONCLUSIONThe present study showed that Simvastatin could promote the regeneration of the sciatic nerve after crush injury in rats, partly through inhibiting immune and inflammatory responses and making the balance of serum cholesterol during these processes.

Animals ; Female ; Nerve Crush ; Nerve Regeneration ; drug effects ; physiology ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve ; drug effects ; injuries ; physiology ; Simvastatin ; pharmacology

Apoptosis ; Humans ; Nerve Regeneration ; Neuroprotective Agents ; pharmacology ; Retinal Ganglion Cells ; drug effects ; physiology ; Stem Cell Transplantation

OBJECTIVETo investigate the effect of pyrroloquinoline quinone (PQQ) on nerve regeneration of transected sciatic nerve in animal models.

METHODSForty SD rats weighing 220-240 g were randomized into a PQQ group (n = 20) and a control group (n = 20). Each animal underwent sciatic nerve transection operation. After the operation, PQQ 0.5 ml (250 microg/Kg) was injected at the operation site in the PQQ group, while the same volume of normal saline was delivered in the control group. Nerve functional evaluation, electrophysiological index recording were carried out according to the experimental design. Newly generated nerve specimens were harvested 12 weeks postoperatively for morphological studies.

RESULTSIn the PQQ group there was a good nerve regeneration and the sciatic nerve function, sciatic nerve function index, electrophysiological index and morphological appearance were superior to the control group (P < 0.05).

CONCLUSIONSPQQ has a remarkable effect in enhancing nerve regeneration of transected peripheral nerve.

Animals ; Male ; Nerve Regeneration ; drug effects ; PQQ Cofactor ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve ; injuries ; pathology ; physiology

OBJECTIVETo investigate the effects of Ginsenoside Rb(1) on the proliferation of Schwann cells in culture.

METHODSApplying MTT assay and Thymidine incorporation assay, the effects of Ginsenoside Rb(1) on the proliferation of Schwann cells isolated from the sciatic nerve of adult rat were studied.

RESULTSGinsenoside Rb(1) (10 microg/ml) significantly induced Schwann cell proliferation, the effect was similar to NGF (50 microg/ml). At high concentrations of Ginsenoside Rb(1) (1 mg/ml), the proliferation of Schwann cells was significantly inhibited.

CONCLUSIONSGinsenoside Rb(1) at the optimal concentrations is found to be effective in inducing the proliferation of Schwann cells, but at higher concentrations the drug is cytotoxic for Schwann cells.

Animals ; Cell Division ; drug effects ; physiology ; Cells, Cultured ; Dose-Response Relationship, Drug ; Ginsenosides ; adverse effects ; pharmacology ; Immunohistochemistry ; Nerve Regeneration ; drug effects ; Probability ; Rats ; Rats, Inbred Strains ; Schwann Cells ; drug effects ; physiology ; Sciatic Nerve ; cytology ; physiology ; Sensitivity and Specificity

OBJECTIVETo explore the effect of kallikrein-binding protein (KPB) in protecting retinal ganglion cells (RGCs) and promoting axonal regeneration following optical nerve injury in rats.

METHODSCrush injury of the optic nerve at 0.5-1.0 mm from the eyeball was induced in rats, which received subsequent KBP injection into the vitreous cavity (experimental group) and PBS injection (control group). At 7, 14 and 21 days after the injury, the rats were sacrificed and frozen sections of the eyeball were prepared to observe the structure and thickness of the retina and count the number of survival RGCs with HE staining. The optic nerves were collected for Western blotting to assess the effect of KBP on the RGCs and axonal regeneration.

RESULTSRGC counts and retinal thickness showed significant differences between the two groups. Western blotting also demonstrated a significant difference in the expression of the nerve regeneration marker protein GAP-43 between the two groups.

CONCLUSIONKBP offers protection on RGCs and promotes regeneration of the optic nerve axons after optic nerve injury in rats.

Animals ; Axons ; physiology ; Female ; GAP-43 Protein ; metabolism ; Nerve Regeneration ; drug effects ; physiology ; Neuroprotective Agents ; pharmacology ; Optic Nerve Injuries ; drug therapy ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells ; drug effects ; physiology ; Serpins ; pharmacology

OBJECTIVETo set up a platform for phenotype-based primary screening of drug candidates promoting neuronal subtype differentiation in embryonic stem cells (ES) with light microscope.

METHODSHanging drop culture 4-/4+ method was employed to harvest the cells around embryoid body (EB) at differentiation endpoint. Morphological evaluation for neuron-like cells was performed with light microscope. Axons for more than three times of the length of the cell body were considered as neuron-like cells. The compound(s) that promote neuron-like cells was further evaluated. Icariin (ICA, 10(-6)mol/L) and Isobavachin (IBA, 10(-7)mol/L) were selected to screen the differentiation-promoting activity on ES cells. Immunofluorescence staining with specific antibodies (ChAT, GABA) was used to evaluate the neuron subtypes.

RESULTSThe cells treated with IBA showed neuron-like phenotype, but the cells treated with ICA did not exhibit the morphological changes. ES cells treated with IBA was further confirmed to be cholinergic and GABAergic neurons.

CONCLUSIONPhenotypic screening with light microscope for molecules promoting neuronal differentiation is an effective method with advantages of less labor and material consuming and time saving, and false-positive results derived from immunofluorescence can be avoided. The method confirms that IBA is able to facilitate ES cells differentiating into neuronal cells, including cholinergic neurons and GABAergic neurons.

Animals ; Cell Differentiation ; drug effects ; physiology ; Cell Line ; Drug Evaluation, Preclinical ; methods ; Embryoid Bodies ; cytology ; Embryonic Stem Cells ; cytology ; Mice ; Nerve Regeneration ; drug effects ; Neurons ; cytology ; Phenotype

OBJECTIVETo study the effect of compound injection of Radix Hedysari on peripheral nerve regeneration in rats.

METHODSSeventy-five healthy adult SD male rats, weighing 150 g, were randomized into 5 groups (15 rats in each group). The bilateral sciatic nerves of the rats were exposed and clamped with a smooth clamp to make an injury area of 2 mm. After clamp operation Group 1 was injected with compound injection of radix Hedysari (CIRH) 1.5 ml/day, Group 2 with CIRH 1.0 ml/day, Group 3 with CIRH 0.5 ml/day, Group 4 with nerve growth factor (NGF) 50 U/day, and Group 5 was taken as the control group without any management. The bilateral sciatic nerve was taken out at 3 days, 1, 2 and 4 weeks after clamping, stained with osmic acid and observed microscopically. The myelinated nerve fibers were counted. The nerve conduction velocity was determined 2 and and 4 weeks before sample taking the sciatic nerve function index was measured 4 weeks before sample taking.

RESULTSThe results of nerve conduction velocity, the myelinated nerve fiber count and the sciatic functuion index in the CIRH treated groups were better than those in the control group. The results of the nerve conduction velocity and the myelinated nerve fiber count at 2 weeks and the nerve conduction velocity at 4 weeks in Group 1 were better than those of Group 4. Biological observation showed that degenerated and necrotic myelin sheath in CIRH treated Groups at 2 and 4 weeks decreased remarkably compared to the NGF treated group.

CONCLUSIONSCIRH can promote regeneration of peripheral nerves and absorption of degenerated and necrotic injured nerves. It has the same effect as NGF.

Animals ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; pharmacology ; Injections, Intralesional ; Male ; Nerve Crush ; Nerve Fibers ; drug effects ; physiology ; Nerve Regeneration ; drug effects ; Peripheral Nerves ; drug effects ; physiology ; Probability ; Rats ; Rats, Sprague-Dawley ; Reference Values ; Sciatic Nerve ; drug effects ; physiology ; Treatment Outcome ; Wounds and Injuries ; drug therapy ; physiopathology

OBJECTIVETo evaluate the effect of human hair keratin (HHK) in peripheral nerve repair and explore the mechanism of sciatic nerve regeneration.

METHODSRat models of sciatic nerve damage was established by creating a 10-mm gap in the sciatic nerve, which was bridged with a HHK implant. Histological examinations of the nerve tissues were performed at different time points after the surgery.

RESULTSDuring the period from 2 days to 2 weeks following HHK implantation, Schwann cells were found to undergo dedifferentiation and proliferate along the HHK implant. Three weeks after HHK implantation, numerous macrophages and megakaryocytes occurred around the HHK, and a large quantity of regenerated Schwann cells aligned in orderly fashion was seen between the fine filaments of partially degraded HHK, where axons and capillaries were also observed. Six weeks later, massive nerve fibers and capillaries developed around the HHK, and at 9 weeks, the HHK implant was substantially degraded and numerous regenerated nerve fibers occurred characterized by obvious epineurium and perineurium. Till 12 weeks after HHK implantation, HHK was almost completely degraded and replaced by the newly regenerated nerve fibers that had grown across the nerve defect.

CONCLUSIONSHHK is an ideal material for nerve injury repair. Apocytosis plays a key role in the differentiation process of highly differentiated Schwann cells into immature Schwann cells following nerve injury. As a protective mechanism, the axons undergo enclosure and dissociation following injuries, and the intact axons give rise to growth cones that extend fibers of growing buds to competitively bind the one or more Schwann cells, but only one such but finally develops into a complete axon. The nerve fiber barrier membrane is derived from the capillary menchymal stem cells and the outmost vascular barrier membrane. The regeneration of the Schwann cells, axons and the nerve membrane is the result of self-organization through a well synchronized and coordinated mechanism.

Animals ; Female ; Hair ; chemistry ; Humans ; Keratins ; administration & dosage ; pharmacology ; Male ; Nerve Regeneration ; drug effects ; physiology ; Prostheses and Implants ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve ; injuries ; physiopathology

Animals ; Animals, Newborn ; Female ; Hyperbaric Oxygenation ; Hypoxia-Ischemia, Brain ; physiopathology ; therapy ; Nerve Growth Factor ; pharmacology ; Nerve Regeneration ; drug effects ; physiology ; Rats ; Rats, Wistar