Electroacupuncture promotes functional recovery and activates energy metabolism in a rat model of sciatic nerve injury

Background: Electroacupuncture (EA) accelerates repair of peripheral nerve injury. The aim of this study was to explore how EA regulates energy metabolism by examining its effects on glucose transport and mitochondrial dynamic balance in a rat model of sciatic nerve injury. Methods: In experiment 1, expression of glucose transporter (GLUT)4 was measured in n = 16 rats at 1, 3, 5 and 7 days following EA to identify the optimal glucose uptake time. In experiment 2, n = 32 rats were randomly divided into the following four groups: Normal, Injury, EA and ES (electrical stimulation). Three days after sciatic nerve injury modeling, micro-positron emission tomography/computed tomography (PET/CT) was performed to observe glucose uptake in the sciatic nerve and surrounding tissues. After 1 week, we measured nerve conduction velocity and expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), mitofusin (Mfn)1/2 and dynamin-related protein (Drp)1 in the sciatic nerve (by Western blotting) and observed pathological changes in the sciatic nerve and gastrocnemius. Results: Protein expression levels of GLUT4, Mfn1/2 and Drp1 were significantly higher in the EA group, and histopathological changes were improved, compared with other groups. Glucose uptake by micro-PET/CT in the target area in the EA group was significantly higher than that in the other groups. Furthermore, nerve conduction velocity and NGF/BDNF expression was significantly higher in the EA group compared with the other three groups. Conclusion: EA accelerated the repair and regeneration of the injured sciatic nerve, activated glucose transport and improved mitochondrial dynamic balance, in a rat model.