Electroacupuncture of scalp acupoint alleviates cerebral ischemic inflammatory injury by down-regulating RORγt and promoting balance of IL-17A+Th17/FOXP3+Treg in MCAO rats. / 电头针调控RORγt促进IL-17A+Th17/FOXP3+Treg细胞平衡缓解MCAOå¤§é¼ è„‘ç¼ºè¡€ç‚Žæ€§æŸä¼¤çš„ç ”ç©¶.

OBJECTIVES: To observe the effect of electroacupuncture (EA) of scalp acupoint (Dingnieqian-xiexian, MS6) on expression of retinoid-related orphan receptor γT (ROR γ t), interleukin (IL)-17A, IL-10, transfor-ming growth factor-ß1 (TGF-ß1), IL-6, IL-21, and IL-17A+ Thelper cells(Th) 17 and forkhead transcription factor P3 (FOXP3)+ regulatory T cells (Treg) differentiation of ischemic cortex in ischemic stroke rats, so as to explore its molecular mechanisms underlying relief of inflammatory injury of ischemic stroke. METHODS: A total of 120 male SD rats were randomly assigned to sham operation, model, EA, inhibitor, agonist and EA+agonist groups, with 15 rats in each group. The ischemic stroke model was established by occlusion of the left middle cerebral artery according to Longa's methods. For rats of the EA group and EA+agonist group, EA (2 Hz/100 Hz, 1 mA) was applied to bilateral MS6 for 30 min, once daily for 7 days. Rats of the inhibitor group received intraperitoneal injection of solution of SR1001 (RORγt inhibitor) (2.5 mg/mL, 10 mg/kg), once daily for 7 days. Rats of the agonist and EA+agonist groups received intraperitoneal injection of solution of SR1078 (RORγt agonist) (5 mg/mL, 5 mg/kg) before EA, once daily for 7 days. Rats of the sham operation and model groups were grabbed and fixed in the same way with the other groups. The Zea-longa's score, modified neurological severity score (mNSS) and the neurobehavioral score were assessed before and after the intervention. At the end of experiments, the ischemic cortex tissue was collected. The 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining was used to detect the volume of cerebral infarction. The expression of RORγt mRNA was detected by real-time quantitative PCR；the protein expression levels of RORγt, IL-17A, IL-10 and TGF-ß1 were detected by Western blot；the immunoactivity of IL-6 and IL-21 were detected by immunohistochemistry；the fluorescence areas of IL-17A+Th17 and FOXP3+Treg cells were measured by immunofluorescence and their ratio was calculated in the tissue of ischemic cortex. RESULTS: Relevant to the sham operation group, the model group had a significant increase in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01), and an obvious decrease in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.01). In contrast to the model group, both EA and inhibitor groups had a significant decrease in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01, P<0.05), and a marked increase in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.05, P<0.01), while the above indicators of the agonist group were all reversed (P<0.01, P<0.05). Comparison between the agonist and EA+agonist groups showed that the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg were significantly lower (P<0.01, P<0.05), and the expression of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity were obviously higher (P<0.01, P<0.05) in the EA+agonist group than in the agonist group, suggesting that EA intervention can effectively weaken the effects of RORγt agonist. CONCLUSIONS: EA of scalp acupoint MS6 can effectively improve the neurological function, behavior reaction and reduce cerebral infarct volume in ischemic stroke rats, which may be associated with its functions in down-regulating the expression of RORγt and promoting the balance of IL-17A+Th17/FOXP3+Treg to alleviate inflammatory injury after ischemic stroke.

[Effects of electro-scalp acupuncture on inflammatory response and microglial polarization in the ischemic cortex of rats with ischemic stroke].

OBJECTIVE: To observe the effects of electro-scalp acupuncture （ESA） on the expression of microglial markers CD206 and CD32, as well as interleukin (IL)-6, IL-1ß, and IL-10 in the ischemic cortex of rats with ischemic stroke, and to explore the mechanisms of ESA on alleviating inflammatory damage of ischemic stroke. METHODS: Sixty 7-week-old male SD rats were randomly selected, with 15 rats assigned to a sham surgery group. The remaining rats were treated with suture method to establish rat model of middle cerebral artery occlusion (MCAO). The rats with successful model were randomly divided into a model group, a VitD3 group, and an ESA group, with 15 rats in each group. In the ESA group, ESA was performed bilaterally at the "top-temporal anterior oblique line" with disperse-dense wave, a frequency of 2 Hz/100 Hz, and an intensity of 1 mA. Each session lasted for 30 min, once daily, for a total of 7 days. The VitD3 group were treated with intragastric administration of 1,25-dihydroxyvitamin D3 (1,25-VitD3) solution (3 ng/100 g), once daily for 7 days. The neurological deficit scores and neurobehavioral scores were assessed before and after the intervention. After the intervention, the brain infarct volume was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Immunofluorescence double staining was performed to detect the protein expression of CD32 and CD206 in the ischemic cortex. Western blot analysis was conducted to measure the protein expression of IL-6, IL-1ß, and IL-10 in the ischemic cortex. RESULTS: Compared with the sham surgery group, the model group showed increased neurological deficit scores and neurobehavioral scores (P<0.01), increased brain infarct volume (P<0.01), increased protein expression of CD32, IL-6, and IL-1ß in the ischemic cortex (P<0.01), and decreased protein expression of CD206 and IL-10 in the ischemic cortex (P<0.01). Compared with the model group, both the ESA group and the VitD3 group showed decreased neurological deficit scores and neurobehavioral scores (P<0.01), reduced brain infarct volume (P<0.01), decreased protein expression of CD32, IL-6, and IL-1ß in the ischemic cortex (P<0.01), and increased protein expression of CD206 and IL-10 in the ischemic cortex (P<0.01). Compared with the VitD3 group, the ESA group had lower neurological deficit score (P<0.05), larger brain infarct volume (P< 0.05), and lower protein expression of CD32, CD206, IL-1ß, and IL-10 in the ischemic cortex (P<0.01, P<0.05). CONCLUSION: ESA could improve neurological function in MCAO rats, and its mechanism may be related to promoting microglial M1-to-M2 polarization and alleviating inflammatory damage.