Using electroacupuncture and moxibustion to treat peripheral nerve injury is highly efficient with low side effects. However, the electroacupuncture- and moxibustion-based mechanisms underlying nerve repair are still unclear. Here, in vivo and in vitro experiments uncovered one mechanism through which electroacupuncture and moxibustion affect regeneration after peripheral nerve injury. We first established rat models of sciatic nerve injury using neurotomy. Rats were treated with electroacupuncture or moxibustion at acupoints Huantiao (GB30) and Zusanli (ST36). Each treatment lasted 15 minutes, and treatments were given six times a week for 4 consecutive weeks. Behavioral testing was used to determine the sciatic functional index. We used electrophysiological detection to measure sciatic nerve conduction velocity and performed hematoxylin-eosin staining to determine any changes in the gastrocnemius muscle. We used immunohistochemistry to observe changes in the expression of S100-a specific marker for Schwann cells-and an enzyme-linked immunosorbent assay to detect serum level of nerve growth factor. Results showed that compared with the model-only group, sciatic functional index, recovery rate of conduction velocity, diameter recovery of the gastrocnemius muscle fibers, number of S100-immunoreactive cells, and level of nerve growth factor were greater in the electroacupuncture and moxibustion groups. The efficacy did not differ between treatment groups. The serum from treated rats was collected and used to stimulate Schwann cells cultured in vitro. Results showed that the viability of Schwann cells was much higher in the treatment groups than in the model group at 3 and 5 days after treatment. These findings indicate that electroacupuncture and moxibustion promoted nerve regeneration and functional recovery; its mechanism might be associated with the enhancement of Schwann cell proliferation and upregulation of nerve growth factor.

SCOPE:Recent findings indicate that ketogenic diet is neuroprotective and electrical stimulation can improve functional recovery from peripheral nerve injury. However, it is not clear whether ketogenic diet and electrical stimulation play synergistical role in the peripheral nerve recovery following injury.

METHODS AND RESULTS:We used ketogenic diet consisting of 3:1 ratio of fat to carbohydrate+protein and coupled it with electrical stimulation treatment in a rat model of peripheral nerve crush injury. Neuromuscular recovery was evaluated by electromyography, and axonal regeneration and myelination by histological methods. We also investigated the effects on IGF-1 and IGF-1 receptor expression in peripheral nerve tissue, pre- and post-nerve injury. Combination of ketogenic diet and electrical stimulation synergistically increased muscle force in biceps femoris and gluteus maximus and prevented development of hypersensitivity in biceps femoris. It promoted peripheral nerve regeneration by increasing total axons, axons density, and axonal diameter, as well as myelin thickness and axon/fiber ratio. These effects were due to modulation of IGF system as the treatment expression of IGF-1 and IGF-1 receptor in regenerated nerve tissue.

CONCLUSION:Our results establish that ketogenic diet and electrical stimulation promote peripheral nerve regeneration. Patients recovering from peripheral nerve injury may benefit from this combinational approach. This article is protected by copyright. All rights reserved.

OBJECTIVE:Peripheral nerve injury is a common, important problem that lacks a definitive, effective treatment. It can cause neurologic deficits ranging from paresthesia to paralysis. This study evaluated the effect of ozone therapy on sciatic nerve crush injury in rats.

MATERIALS AND METHODS:Twenty-four male rats were divided into control sham surgery, sciatic nerve injury, and sciatic nerve injury with ozone groups (each n = 8). The sciatic nerve injury was inflicted via De Koning's crush-force method. The sciatic nerve injury group received medical air and the sciatic nerve injury ozone group received 0.7 mg/kg ozone. Sciatic nerve samples were obtained 4 weeks after injury. Vascular congestion, vacuolization, edema formation, S100 expression, and the thicknesses of the perineurium and endoneurium and diameter of the injured sciatic nerves were evaluated.

RESULTS:The diameter of the sciatic nerve and thicknesses of the perineurium and epineurium were significantly greater in the sciatic nerve injury group (P <0.05) and significantly less in the sciatic nerve injury with ozone group (P<0.001). High S100 immunoreactivity was seen in the sciatic nerve injury group compared with the other 2 groups (P<0.05). The distributions of vascular congestion and vacuolization were significantly less in the sciatic nerve injury with ozone group (P < 0.05).

CONCLUSIONS:Ozone therapy improved sciatic nerve injury recovery without causing an increase in fibrotic tissue. Ozone reduced fibrosis, vascular congestion, vacuolization, and edema in rodents. Ozone treatment might be used to assist in sciatic nerve injury.