Electroacupuncture regulates microglial polarization via inhibiting NF-κB/COX2 pathway following traumatic brain injury.

BACKGROUND: Neuroinflammation and oxidative stress are important pathological mechanisms following traumatic brain injury (TBI). The NF-κB/COX2 pathway regulates neuroinflammation and oxidative damage, while microglia also play an important role in neuroinflammation. Since NF-κB is involved in microglial polarization, targeting this pathway and microglial polarization is a critical component of TBI treatment. Currently, electroacupuncture (EA) is widely used to treat various symptoms after TBI, but the mechanisms of EA remain poorly understood. Additionally, the optimal frequency of EA remains unclear, which affects its efficacy. This study focuses on exploring the optimal frequency parameters of EA on TBI and investigating the underlying mechanisms of EA through NF-κB/COX2 pathway and microglial polarization. METHODS: The study was divided into two parts. In Experiment 1, 42 Sprague Dawley (SD) rats were induced and randomly divided into seven groups (n = 6). Except for the sham group, all rats underwent controlled cortical impact (CCI) to establish TBI model. Four EA groups (with different frequencies) and manual acupuncture (without current stimulation) received stimulation on the acupoints of Shuigou (GV26), Fengchi (GB20) and Neiguan (PC6) once a day for 7 days. The neurological function was assessed by modified Neurological Severity Scores (mNSS), and the rats' memory and learning were examined by the Morris water maze (MWM). SOD, MDA, and GSH-Px were detected to evaluate the levels of oxidative stress. The levels of IL-1ß, IL-6, and TNF-α were evaluated by Enzyme Linked Immunosorbent Assay (ELISA). Detection of the above indicators indicated a treatment group that exerted the strongest neuroprotection against TBI, we then conducted Experiment 2 using this screened acupuncture treatment to investigate the mechanism of acupuncture. 48 rats were randomly divided into four groups (n = 12): sham, TBI model, acupuncture and PDTC (NF-κB inhibitor). Evaluations of mNSS, MWM test, SOD, MDA, GSH-Px, IL-1ß, IL-6, TNF-α, and IL-10 were the same as in Experiment 1. Western blot was applied for detecting the expression levels of NF-κB, p-NF-κB, COX2, and Arg-1. TUNEL was used to examine neuronal apoptosis. Brain structure was observed by H&E. Iba-1, COX2, and Arg-1 were investigated by immunofluorescence staining. RESULTS: EA with frequency of 2/100 Hz markedly improved neuronal and cognitive function as compared to the other treatment groups. Moreover, it downregulated the expression of MDA, IL-6, IL-1ß, and TNF-α and upregulated the levels of SOD and GSH-Px. In addition, Both EA with 2/100 Hz and PDTC reduced the levels of p-NF-κB, COX2 and M1 markers (COX2, IL-6, IL-1ß, TNF-α) and increased the levels of M2 markers (Arg-1, IL-10). Moreover, they had similar effects on reducing inflammation, oxidative stress and apoptosis, and improving neuronal and cognitive function. CONCLUSIONS: The collective findings strongly suggest that EA with 2/100 Hz can improve neurologic function by suppressing neuroinflammation, oxidative stress and apoptosis. Additionally, we confirm that EA promotes microglial polarization towards the M2 phenotype through the suppression of NF-κB/COX2 pathway, thus exerting neuroprotective effects after TBI.

[Progress of researches on mechanism of acupuncture for traumatic brain injury].

Acupuncture therapy has been shown to have a positive effect in treating symptoms of patients with traumatic brain injury (TBI) in China. The present paper summarizes findings of recent researches on the underlying mechanisms of acupuncture intervention for improving TBI from 1) inhibiting inflammatory response, 2) regulating neurotransmitters, 3) promoting nerve repair and regeneration, 4) antioxidation, 5) inhibiting intracellular calcium overload, 6) regulating aquaporin content, 7) regulating cellular energy metabolism, 8) improving brain circulation, and 9) inhibiting cell apoptosis.

[Comparison of efficacy on functional constipation treated with electroacupuncture of different acupoint prescriptions: a randomized controlled pilot trial].

OBJECTIVE: To evaluate preliminarily the efficacy on functional constipation treated with electroacupuncture of different acupoint prescriptions. METHODS: One hundred and four patients were randomized into a front-mu and back-shu points group (19 cases), a he-sea points group (34 cases), a he-sea, front-mu and back-shu points group (26 cases) and a western medication control group (25 cases). In the front-mu and back-shu points group, electroacupuncture was applied at bilateral Tianshu (ST 25) and Dachangshu (BL 25). In the he-sea points group, electroacupuncture was applied at bilateral Quchi (LI 11) and Shangjuxu (ST 37). In the he-sea, front-mu and back-shu points group, electroacupuncture was applied at unilateral Tianshu (ST 25), Dachangshu (BL 25), Quchi (LI 11) and Shangjuxu (ST 37). In the three groups above, the treatment was given 5 times a week in the first two weeks and 3 times a week in the next two weeks. In the western medication control group, mosapride citrate tablets were prescribed for oral administration, 1 table (5 mg) each time, 3 times a day, continuously for 4 weeks. The period of research was 9 weeks, including 1 week for baseline evaluation, 4 weeks for treatment and 4 weeks for follow-up. The weekly defecation frequency was taken as primary index, while the defecation difficulty and life quality score were taken as the secondary indices for the efficacy evaluation after treatment and in follow-up. RESULTS: According to the intention-to-treat (ITT) analytic principle, 104 cases were all enrolled in the final analysis. (1) After treatment, the weekly frequency of defecation was all increased significantly in the four groups (P < 0.05, P < 0.01). The efficacy of the three electroacupuncture groups was similar to that of western medication control group (P > 0.05). In follow-up, the increasing effect on the weekly frequency of defecation was maintained in the he-sea points group (P < 0.01), superior to the front-mu and back-shu points group and the western medication control group (P < 0.05, P < 0.01); the weekly frequency of defecation was not improved in the rest three groups (P > 0.05). (2) After treatment, defecation difficulty was relieved in the he-sea points group, the he-sea, front-mu and back-shu points group and the western medication control group (P < 0.05, P < 0.01). In follow-up, the improvements were still significant in the he-sea points group and the he-sea, front-mu and back-shu points group (both P < 0.01). (3) After treatment, the life quality score was significantly improved in the patients of the he-sea points group (P < 0.05). The difference was not significant in the rest three groups as compared with that before treatment (all P > 0.05). CONCLUSION: The weekly frequency of defecation is increased effectively after treatment in the three electroacupuncture groups and the efficacy is similar to mosapride citrate tablets. The bilateral Quchi (LI 11) and Shangjuxu (ST 37) in he-sea acupoints increase significantly the weekly frequency of defecation, relieve defecation difficulty and improve life quality. Acupuncture efficacy is sustained for 4 weeks. This acupoints prescription is the best in the treatment of functional constipation.