Effect of electroacupuncture intervention on expression of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor in injured segments of rats with spinal cord injury / 中国组织工程研究

ABSTRACT

BACKGROUND: The authors found a striking similarity between the qi and blood theory and nerve repair of spinal cord injury in terms of improving blood-oxygen microenvironment in tissues. The hypothesis is that electroacupuncture can improve the blood-oxygen microenvironment of the spinal cord and promote nerve regeneration by regulating hypoxia-inducible factor 1a and vascular endothelial growth factor signal transduction. OBJECTIVE: To investigate the effect of electroacupuncture intervention on the expression of hypoxia-inducible factor 1a and vascular endothelial growth factor in injured segments of spinal cord injury rats. METHODS: Totally 120 Sprague-Dawley female rats were enrolled to make spinal cord injury models by clamping the spinal cord (20 seconds) using a microvascular clamp. Rat models were then randomly divided into three groups Ashi point group, Stomach Meridian of Foot-Yangming group and blank control group, 40 rats in each group. Electroacupuncture at two Aishi points or at both sides of Futu and Zusanli points was started on the 3rd day after modeling. Each rat was scored on the Basso, Beattie and Bresnahan locomotor rating scale at 1, 2, 3,4, and 5 weeks after intervention. Injured spinal cord specimens were then taken and observed histomorphologically. Hypoxia-inducible factor-1a and vascular endothelial growth factor protein and mRNA expressions were detected using immunohistochemistry staining, real-time fluorescence quantitative PCR and western blot assay. The study protocol was approved by the Animal Ethic Committee of the First Affiliated Hospital of Guangxi University of Chinese Medicine in China (approval No. 201712001). RESULTS AND CONCLUSION: The lower limb function score, hypoxia-inducible factor-1a and vascular endothelial growth factor gene and protein expression in the two electroacupuncture intervention groups were significantly higher than those of the blank control group. The number of neurons in Ashi point and Stomach Meridian of Foot -Yangming groups was significantly higher than that of the blank control group with the lapse of intervention time. Electroacupuncture intervention can effectively improve the lower limb function score of spinal cord injury rats, increase the number of neurons, and up-regulate the mRNA and protein expression of hypoxia-inducible factor-1 a and vascular endothelial growth factor, thus effectively promoting the neurological recovery of the spinal cord.