OBJECTIVETo assess the effect of cyclosporine A (CsA) loaded in chitosan conduit on bridging the sciatic nerve defects in a rat model.

METHODSA 10 mm sciatic nerve defect was bridged using a chitosan conduit filled with 10 μl carrier-drug dilution (10 μg/L CsA). In control group, the conduit was filled with the same volume of carrier dilution alone. The regene-rated fibers were studied 4, 8 and 12 weeks after surgery.

RESULTSThe functional study confirmed faster recovery of the regenerated axons in treatment group than control group (P<0.05). There was statistically significant difference of the gastrocnemius muscle weight ratios between treatment and control groups (P<0.05). Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in CsA-treated animals were significantly higher than those in control group. In immunohistochemistry, the location of reactions to S-100 in CsA group was clearly more positive than control group.

CONCLUSIONCsA loaded in a chitosan conduit results in improvement of functional recovery and quantitative morphometric indices of sciatic nerve. It is easily available without any complications compared with its systemic administration.

Animals ; Chitosan ; Cyclosporine ; administration & dosage ; pharmacology ; Immunohistochemistry ; Nerve Regeneration ; drug effects ; Rats ; Sciatic Nerve ; chemistry ; injuries

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

Diabetic Neuropathies ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Nerve Regeneration ; drug effects

Ginsenoside Rb1 is a representative component of panaxadiol saponins, which belongs to dammarane-type tritepenoid saponins and mainly exists in family araliaceae. It has been reported that ginsenoside Rb1 has diverse biological activities. In this paper, the research development in recent decade on its pharmacological effects of cardiovascular system, anti-senility, reversing multidrug resistance of tumor cells, adjuvant anti-cancer chemotherapy, promoting peripheral nerve regeneration, et al, are reviewed.
Aging ; drug effects ; Animals ; Cardiovascular System ; drug effects ; pathology ; Drug Resistance, Neoplasm ; drug effects ; Ginsenosides ; metabolism ; pharmacokinetics ; pharmacology ; Humans ; Nerve Regeneration ; drug effects

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

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

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 evaluate the local effect of vascular endothelial growth factor (VEGF) on transected sciatic nerve regeneration.

METHODSSixty male white Wistar rats were divided into four experimental groups randomly (n equal to 15). In transected group the left sciatic nerve was transected and the stump was fixed to adjacent muscle. In treatment group the defect was bridged using a silicone graft filled with 10 microlitre VEGF. In silicone group the graft was filled with phosphate-buffered saline. In sham-operated group the sciatic nerve was exposed and manipulated. Each group was subdivided into three subgroups with five animals in each and nerve fibers were studied 4, 8 and 12 weeks after operation.

RESULTSBehavioral test, functional study of sciatic nerve, gastrocnemius muscle mass and morphometric indices confirmed a faster recovery of regenerated axons in VEGF group than in silicone group (P less than 0.05). In immunohistochemical assessment, reactions to S-100 in VEGF group were more positive than that in silicone group.

CONCLUSIONLocal administration of VEGF will improve functional recovery and morphometric indices of sciatic nerve.

Administration, Topical ; Animals ; Nerve Regeneration ; drug effects ; Rats ; Rats, Wistar ; Sciatic Nerve ; surgery ; Vascular Endothelial Growth Factor A

Vascular endothelial growth factor (VEGF) has been found to be the most powerful angiogenic factor. Studies have shown that cerebral ischemia and hypoxia stimulate the expressions of VEGF and its receptors in the brain, while exogenous VEGF promotes the formation of new blood vessels in the ischemic brain penumbra, and reduce the volume of cerebral infarction. The effect of VEGF on cerebral ischemia was previously explained the mechanism that VEGF had a specific mitogenetic roles in cerebral endothelial cells and thus promoted neovascularization; however recent evidence has shown that VEGF also has direct effects on neural and glial cells. Its multiple protection roles on central nervous system involve vascularization, neurogenesis, direct neurotrophic and neuroprotective effect, as well as antiapoptosis effect, especially when brain ischemia occurs. Further elucidation of these mechanisms on central nervous system may serve as a key procedure in understanding the main aspects of neural repair and neural protection, and develop effective therapeutic measures for intervention in stroke.
Animals ; Brain Ischemia ; drug therapy ; physiopathology ; Dose-Response Relationship, Drug ; Neovascularization, Physiologic ; drug effects ; Nerve Regeneration ; drug effects ; Neuroprotective Agents ; pharmacology ; Vascular Endothelial Growth Factor A ; administration & dosage ; pharmacology

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