Role of CCL2/CCR2 signaling pathway in electroacupuncture-induced reduction of spinal cord injury in rats
10.3760/cma.j.cn131073-20240904-00510
- VernacularTitle:CCL2/CCR2信号通路在电针减轻大鼠脊髓损伤中的作用
- Author:
Xiang WANG
1
;
Jianzhong HUO
;
Wei FAN
;
Jing GAO
;
Yangyang SHENG
;
Jie ZHANG
;
Zhaoyu ZHANG
Author Information
1. 山西医科大学第三医院 山西白求恩医院疼痛科，太原 030032
- Publication Type:Journal Article
- Keywords:
Chemokines, CC;
Receptors, chemokine;
Electroacupuncture;
Spinal cord injuries
- From:
Chinese Journal of Anesthesiology
2025;45(5):574-580
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the role of the CC chemokine ligand 2/CC chemokine receptor 2 (CCL2/CCR2) signaling pathway in electroacupuncture (EA)-induced reduction of spinal cord injury (SCI) in rats.Methods:Sixty clean-grade healthy adult female Sprague-Dawley rats, weighing 210-250 g, were divided into 5 groups ( n=12 each) using a random number table method: sham operation group (group S), group SCI, SCI+ Anti-CCL2 group (group SCI+ A), SCI+ EA group (group SCI+ EA), and spinal cord injury+ EA+ rCCL2 group (group SCI+ EA+ R). The SCI model was established using the Allen method in anesthetized animals. Group S only underwent spinous process and laminectomy without damaging the spinal cord. In SCI+ A group, CCL2 neutralizing antibody 50 μg/kg was intrathecally injected at 0, 3 and 6 days after successful development of the SCI model. On the 7th day after the successful development of the SCI model, Jiaji, Dazhui and Mingmen acupoints were stimulated with a depth of 2 mm, voltage of 12-15 mV and frequency of 2 Hz for 30 min once a day for 7 consecutive days in SCI+ EA group. In SCI+ EA+ R group, recombinant rat CCL2 2.5 μg/kg was intrathecally injected at the site of injury at 0, 3 and 6 days after successful development of the SCI model, and the remaining treatments were similar to those in SCI+ EA group. At 1 day before developing the model, 0, 3, 7, 14, 21 and 28 days after developing the model, the mechanical paw withdraw threshold (MWT) and thermal paw withdrawal latency (TWL) were measured, and the motor function was assessed by BBB score. The rats were sacrificed after the final behavioral testing, and their spinal cord tissues were obtained for determination of the expression of CCL2 and CCR2 protein and mRNA (by Western blot or quantitative real-time polymerase chain reaction), the expression of GFAP (by immunofluorescence), contents of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-6 (by enzyme-linked immunosorbent assay) and for examination of the pathological changes (using HE staining). Results:Compared with S group, the MWT and BBB scores were significantly decreased and the TWL was shortened at each time point after developing the model, the expression of CCL2 and CCR2 protein and mRNA and GFAP was up-regulated, and the contents of TNF-α, IL-1β and IL-6 were increased in SCI group ( P<0.05). Compared with SCI group, the MWT and BBB scores were significantly increased, and the TWL was prolonged at 7 days after developing the model in SCI+ A group, the MWT and BBB scores were significantly increased, and the TWL was prolonged at 14 days after developing the model in SCI+ EA group, and the expression of CCL2 and CCR2 protein and mRNA and GFAP was significantly down-regulated, and the contents of TNF-α, IL-1β and IL-6 were decreased in SCI+ A and SCI+ EA groups ( P<0.05). Compared with SCI+ EA group, the MWT and BBB scores were significantly decreased at 14 days after developing the model, the TWL was shortened, the expression of CCL2 and CCR2 protein and mRNA and GFAP was up-regulated, and the contents of TNF-α, IL-1β and IL-6 were increased in SCI+ EA+ R group ( P<0.05). Compared with SCI+ A and SCI+ EA groups, the histopathological injury were significantly attenuated in SCI group, and the histopathological injury was aggravated in SCI+ EA+ R group. Conclusions:The CCL2/CCR2 signaling pathway is involved in the process by which EA reduces SCI, and the mechanism is related to the inhibition of astrocyte activation, thereby reducing the inflammatory response.
