The effect of electroacupuncture on mitochondrial autophagy in neuropathic pain rats: A study based on Keap1/Nrf2 signal pathway
CHENG Bo1, 2, TU Wenzhan1, 2, LOU Xinfa2, YANG Guanhu2, JIANG Songhe1, 2, 3,WU Qiaoyun1, 2, 3.
1.Center of Physical Medicine and Rehabilitation, the Second Affiliated Hospital & Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou 325027, China; 2.Integrative & Optimized mMedicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou 325035, China; 3.Wenzhou Key Laboratory for Rehabilitation Research, the Provincial Key Laboratory for Acupuncture and Rehabilitation in Zhejiang Province, Wenzhou 325027, China
CHENG Bo,TU Wenzhan,LOU Xinfa, et al. The effect of electroacupuncture on mitochondrial autophagy in neuropathic pain rats: A study based on Keap1/Nrf2 signal pathway[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2023, 53(5): 353-358.
Abstract：Objective: To explore the mechanism of electroacupuncture at “Zusanli” and “Kunlun” points in regulating mitochondrial autophagy and alleviating neuropathic pain. Methods: Totally 39 healthy male SD rats were selected. The model group was treated with L5 spinal nerve ligation (SNL). The sham group and the model group had the same operation but no ligation. The electroacupuncture group was treated with electroacupuncture for 7 consecutive days. The mechanical threshold and thermal threshold were detected after operation. L4-6 spinal cord segments were taken and HE staining was used to detect the histopathological changes; Mitochondrial autophagy in dorsal horn of spinal cord was observed by transmission electron microscope; The expression levels of Kelch-like ECH-associated protein-1 (Keap1), nuclear factor erythroid-related factor 2 (Nrf2), BCL2 and adenovirus E1B19 kDa interacting protein 3-like (NIX), BCL2 and adenovirus E1B19 kDa interacting protein 3 (BNIP3) were detected by Western blot. Results: The rats showed obvious pain allergic reaction after operation.Compared with the model group, the electroacupuncture group had the increased pain threshold, with significant difference (P<0.05). HE staining results showed that the morphology and structure of spinal dorsal horn neurons in the sham group were normal; In the model group, the cell nucleus was obviously pyknotic and the cell structure was destroyed; The tissue structure was improved after electroacupuncture treatment. The results of transmission electron microscopy showed that the morphology of mitochondria in pseudo module was regular and the number was small; In the model group, mitochondria were obviously swollen, cells were necrotic and apoptotic, and autophagic lysosomes were found around them. Compared with the model group, the the electroacupuncture group had relatively regular mitochondria, with partial disappearance of the mitochondrial cristae, and there was autophagic lysosome structure in the cells, without obvious necrosis and apoptosis. Western blot results showed that Keap1, Nrf2, NIX and BNIP3 expressions increased in the model group compared with the sham group (P<0.05). Compared with the model group, the electroacupuncture group had decreased Keap1 expression (P<0.05), increased Nrf2, NIX and BNIP3 expression (P<0.05). Conclusion: Electroacupuncture can promote mitochondrial autophagy to relieve neuropathic pain via Keap1/Nrf2 signaling pathway.
