Electroacupuncture Preconditioning Research Articles

Mechanistic study of electroacupuncture preconditioning in alleviating myocardial ischemia-reperfusion injury in rats: involvement of mTOR/ROS signaling pathway to inhibit ferroptosis

Purpose The objective of this study was to investigate the mechanism of electroacupuncture pretreatment in reducing myocardial ischemia-reperfusion injury in rats. Materials and methods The comparison of HR among the different groups did not yield statistically significant differences (p > 0.05). Additionally, the trend of HR change at different time points within each group was not statistically significant (p > 0.05). In contrast, the comparison of SBP among the different groups showed statistically significant differences (p < 0.05). Furthermore, the trend of SBP change at different time points within each group exhibited significant differences (p < 0.05). Results Compared to the Sham group, rats in the I/R group and EA control group showed a significant decrease in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and an increase in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). Compared to EA control group, rats in the EA group exhibited a significant increase in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and a decrease in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). Compared to the EA group, rats in the EA + RAP group showed a significant decrease in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and an increase in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). Conclusions Electroacupuncture preconditioning confers protective effects against myocardial ischemia-reperfusion injury in rats. Its mechanism may involve the activation of the mTOR/ROS signaling pathway by electroacupuncture to inhibit ferroptosis.

Characteristics of Electroacupuncture Preconditioning and Treatment on Regulation of the Brain Transcriptome in Rats with Ischemic Stroke.

Accumulating evidence suggests that acupuncture may serve as a potent strategy to mitigate the deleterious effects of ischemic stroke on neural tissue. The present investigation delineated the neuroprotective potential of electroacupuncture (EA) administered pre-and post-stroke, with a focus on determining the commonalities and disparities between these two therapeutic approaches in ameliorating ischemic stroke-induced brain injury. The ultimate objective is to inform optimal timing for acupuncture intervention in the clinical management and prevention of stroke. The extent of cerebral infarction was quantified with 2,3,5-triphenyltetrazolium chloride staining. The integrity of the blood-brain barrier was assessed by evaluating the extravasation of Evans blue (EB) dye, while neurological function was appraised using the Longa neurological scoring system. RNA sequencing was employed to examine the transcriptomic landscape of ischemic brain tissue, with subsequent bioinformatics annotation of the sequencing data facilitated by Metascape. (1) A notable decrease in the ischemic infarct volume was observed in both the EA-preconditioned plus middle cerebral artery occlusion (MCAO), EA-preconditioned plus middle cerebral artery occlusion (EAM) and MCAO plus EA-treated (MEA) groups, compared to the MCAO group. Furthermore, the decreased leakage of EB and reduction in neurological function impairment scores were evident in the EAM and MEA groups compared with the MCAO group. (2) Relative to the Sham group, the MCAO group exhibited a total of 4798 differentially expressed genes (DEGs), with 67.84% demonstrating an expression fold change (FC) greater than 1.5, and 34.16% exceeding a FC of 2. The EAM and MEA groups displayed 4020 and 1956 DEGs, respectively, compared to the MCAO group. In both groups, more than 55% of DEGs showed an expression FC surpassing 1.5, whereas only approximately 10% exhibited a change greater than 2-fold. Remarkably, EA preconditioning and EA treatment resulted in the reversal of 18.72% and 28.91% of DEGs, respectively, in the MCAO group. (3) The DEGs upregulated in response to ischemic stroke were predominantly implicated in immune inflammatory processes and cellular apoptosis, whereas the downregulated DEGs were associated with neurogenesis and neuronal signal transduction. The MEA-induced upregulated DEGs were primarily involved in neural transmission and metabolic processes, whereas the downregulated DEGs were linked to excessive inflammatory responses to physical and chemical stimuli, as well as cell matrix adhesion chemotaxis. In the context of EAM, the upregulated DEGs were chiefly related to protein biosynthesis, and energy and metabolic processes, whereas the downregulated genes were connected to gene transcriptional activity, synaptic function, and neuronal architecture. Both preconditioning and post-event treatment with acupuncture demonstrated efficacy in mitigating pathological damage to brain tissue in a rat model of ischemic stroke, albeit with some divergences in their gene targets. The integration of EA preconditioning and treatment may potentially confer enhanced neuroprotection in the clinical management of stroke patients.

Electroacupuncture preconditioning protects against myocardial ischemia-reperfusion injury by modulating dynamic inflammatory response

BackgroundThe protective effects of electroacupuncture (EA) preconditioning against myocardial ischemia-reperfusion injury (MIRI) have been reported. However, the underlying mechanism remains unclear. Recent research has indicated that the dynamic inflammatory response following MIRI plays an essential role in the progression of myocardial injury. This study aimed to investigate the myocardial protective effects of EA preconditioning on MIRI in rats and to explore the relevant mechanism from the perspective of dynamic inflammatory response. MethodsA MIRI model was employed, and the rats were subjected to EA on Neiguan for four days prior to modeling. The myocardial protective effect of EA preconditioning was evaluated by echocardiography, Evans blue and triphenyltetrazolium chloride staining. Real-time polymerase chain reaction, Western blot, hematoxylin & eosin staining, and immunohistochemistry were utilized to detect the content of mitochondrial DNA, NOD receptor family protein 3 (NLRP3) inflammasome activation, neutrophil recruitment and macrophage infiltration in blood samples and myocardium below the ligation. ResultsWe found that EA preconditioning could accelerate the recovery of left ventricle function after MIRI and reduce the myocardial infarction area, thereby protecting the myocardium against MIRI. Furthermore, EA preconditioning was observed to ameliorate mitochondrial impairment, reduce the level of plasma mitochondrial DNA, modulate NLRP3 inflammasome activation, attenuate neutrophil infiltration, and promote the polarization of M1 macrophages towards M2 macrophages in the myocardium after MIRI. ConclusionEA preconditioning could reduce plasma mtDNA, suppress overactivation of the NLRP3 inflammasome, facilitate the transition from the acute pro-inflammatory phase to the anti-inflammatory reparative phase after MIRI, and ultimately confer cardioprotective benefits.

Effect of electroacupuncture pretreatment on ferroptosis in neurons of rats with cerebral ischemia-reperfusion injury

To observe the effect of electroacupuncture（EA）preconditioning on ferroptosis in rats with cerebral ischemia-reperfusion injury （CIRI）, so as to explore the neuroprotective mechanism of EA preconditioning. Male SD rats were randomly divided into sham operation, model, EA, inhibitor and inducer groups with 20 rats in each group. The CIRI model was established by modified Zea Longa occlusion of the middle cerebral artery. Before modeling, EA treatment （2 Hz/15 Hz, 1-2 mA） was applied to "Baihui"（GV20）, "Fengfu"（GV16） and "Dazhui"（GV14） for rats of the EA group, 20 min a day for 7 consecutive days. Rats of the inhibitor group were intraperitoneally injected with ferristatin-1（25 mg/kg）at a slow and uniform rate. Rats of the inducer group were intraperitoneally injected with Erastin（100 mg/kg） after 7 days of EA preconditioning, once every 2 h for a total of 4 times. The CIRI models were prepared 2 d later after the above interventions finished by thread-occlusion. The degree of neurological impairment was evaluated by modified Zea Longa score. The percentage of infarct size was calculated by TTC staining. The ultrastructure of neurons in hippocampus was observed by transmission electron microscope. The contents of ferrous ion （Fe2+）, malondialdehyde （MDA） and glutathione （GSH） in cerebral tissue and reactive oxygen species （ROS） in serum were determined by biochemical method. The changes of mitochondrial membrane potential in rats brain tissues were detected by flow cytometry. The mRNA and protein expression levels of glutathione peroxidase 4 （GPX4）, acyl-CoA synthetase long-chain family member 4 （ACSL4）, transferrin receptor （TFRC）, 15-lipoxygenase （15-LOX） and cyclooxygenase-2 （COX-2） in the ischemic hippocampal region of CIRI rats were detected by real-time quantitative PCR and Western blot, respectively. Compared with the sham operation group, the neurological impairment score, the percentage of cerebral infarction area, the contents of MDA and Fe2+ in cerebral tissue as well as ROS in serum, the protein and mRNA expression levels of ACSL4, TFRC, 15-LOX, COX-2 in hippocampal tissue were increased （P<0.01）, while the content of GSH in cerebral tissue, the protein and mRNA expression levels of GPX4 in hippocampal tissue were decreased （P<0.01）, and mitochondria in brain tissue were significantly damaged （P<0.01） in the model group. Compared with the model group, the above indexes were all reversed （P<0.05, P<0.01） in the EA group and inhibitor group. Compared with the EA group, the neurological impairment score, the percentage of cerebral infarction area, the contents of MDA and Fe2+ in cerebral tissue as well as ROS in serum, the protein and mRNA expression le-vels of ACSL4, TFRC, 15-LOX, COX-2 in hippocampal tissue were increased （P<0.05, P<0.01）, while the content of GSH in cerebral tissue, the protein and mRNA expression levels of GPX4 in hippocampal tissue were decreased （P<0.01, P<0.05）, and mitochondria in brain tissue were significantly damaged （P<0.05） in the inducer group. EA preconditioning has neuroprotective effect on CIRI rats, which may be related to inhibiting ACSL4/TFRC/15-LOX/COX-2 expression and increasing GSH/GPX4 expression.

Electroacupuncture attenuates myocardial ischemia-reperfusion injury by inhibiting microglial engulfment of dendritic spines

A major side effect of reperfusion therapy following myocardial infarction is myocardial ischemia-reperfusion injury (MIRI). Electroacupuncture preconditioning (EA-pre) has a long history in the treatment of cardiovascular diseases. Here, we demonstrate how EA-pre attenuates MIRI by affecting the phagocytosis of neuronal dendritic spines of microglia of the fastigial nucleus (FNmicroglia). We observed that EA-pre increased activity in FNGABA and then improved myocardial injury by inhibiting abnormal activities of glutaminergic neurons of the FN (FNGlu) during MIRI. Interestingly, we observed changes in the quantity and shape of FN microglia in mice treated with EA-pre and a decrease in the phagocytosis of FNGABA neuronal dendritic spines by microglia. Furthermore, the effects of improving MIRI were reversed when EA-pre mice were chemically activated by intra-FN lipopolysaccharide injection. Overall, our results provide new insight indicating that EA-pre regulates microglial engulfment capacity, thus promoting the improvement of cardiac sympathetic nervous disorder during MIRI.

Effects of electroacupuncture pretreatment on long-term postoperative cognitive dysfunction and neuron-inflammation in aged rats

To observe the effects of electroacupuncture pretreatment on postoperative cognitive dysfunction (POCD), neuronal apoptosis and neuron-inflammation in aged rats. Thirty-six male SD rats aged 20 months were randomly divided into sham operation group, model group and electroacupuncture (EA) group, with 12 rats in each group. The POCD rats model was prepared by internal fixation of left tibial fracture. Five days before modeling, EA stimulation (2 Hz/15 Hz, 1 mA, 30 min) was applied to "Zusanli" (ST36), "Hegu" (LI4) and "Neiguan" (PC6) on the unaffected side of rats in the EA group, once a day for consecutive 5 d. The learning and memory abilities of rats were evaluated by water maze test 31-35 days after operation. The apoptosis of hippocampal neurons was observed by Tunel/NeuN double staining. The expressions of high mobility group protein B1 (HMGB1) and phosphorylated (p)-nuclear factor (NF)-κB in microglia cells in hippocampal dentate gyrus were detected by immunofluorescence staining. The expression levels of interleukin (IL)-6 and IL-1β in the hippocampus were detected by Western blot. Compared with the sham operation group, the escape latency was prolonged (P<0.05); the frequency of crossing the original platform, ratio of the swimming distance and the time in the target quadrant of the Morris water maze were significantly decreased (P<0.05); the apoptosis rate of hippocampal neurons was significantly increased (P<0.05); the expressions of HMGB1 and p-NF-κB in microglia cells in the dentate gyrus and the expression levels of IL-6 and IL-1β in hippocampus were increased (P<0.05) in the model group. Compared with the model group, the results of the above indexes were all opposite (P<0.05) in the EA group. EA preconditioning can regulate hippocampal inflammatory response, alleviate neuronal apoptosis rate and long-term cognitive dysfunction in aged rats with POCD, the mechanisms may be related to the inhibition of microglia HMGB1/NF-κB pathway in hippocampal dentate gyrus.

Effect of acupuncture pretreatment of "Quchi"(LI11) and "Xuehai" (SP10) on mast cells and IL-33/ST2 in rats with urticaria

To observe the effect of electroacupuncture (EA) pretreatment at "Quchi "(LI11) and "Xuehai "(SP10) on expression of interleukin (IL)-33, suppression of tumorigenicity 2 (ST2) and mast cell degranulation in sensitive area of skin tissue in rats with urticaria, so as to explore its mechanisms underlying prevention of urticaria. A total of 32 male SD rats were randomly divided into blank control, model, EA preconditioning and medication groups, with 8 rats in each group. The urticaria model was established by topical injection of the prepared anti-ovalbumin serum (foreign serum, 0.1 mL/spot) along the bilateral sides of the spinal column on the back, followed by injection of mixture solution of ovalbumin, 0.5% evans blue and normal saline via the tail vein 48 h later. EA intervention (2 Hz/15 Hz, 1 mA) was applied to bilateral LI11 and SP10 for 20 min, once daily for 7 d before modeling.Back sensitization was started from the 5th day on. Rats of the medication group received gavage of loratadine, and those of the model group received gavage of the same volume of normal saline. The diameter of evans blue spots at the back skin tissue was measured; the histopathological changes of the blue spot tissues were observed by light microscope after H.E. staining. The state of degranulation of mast cells in the subcutaneous loose connective tissue was observed by using toluidine blue staining. Serum IgE and histamine contents were detected by ELISA, and the immunoactivity of IL-33 and ST2 in the skin and subcutaneous tissues of the sensitized spots (evans blue exudation spots) was observed by immunohistochemistry. Compared with the blank control group, the diameter of evans blue spot, degranulation rate of mast cells, serum IgE and histamine contents, and the immunoactivity of IL-33 and ST2 in the evans blue exudation spot tissues were significantly increased in the model group (P<0.01). In comparison with the model group, the increase of the above-mentioned indexes was reversed in both EA and medication groups (P<0.01，P<0.05). No significant differences were found between the EA and medication groups in down-regulating the levels of the 6 indexes. H.E. staining of the blue spot tissues of rats in the model group showed incomplete structure of the epidermal layer of the skin, unclear interface of tissues, incomplete keratinization, chaotic epidermal cells, disorderly arrangement of fibers in the dermis, and infiltration of inflammatory cells and edema, which was relatively milder in the EA and medication groups. EA preconditioning can prevent urticaria (reduce size and sensitive reactions) in rats, which may be associated with its functions in lowering the level of IgE through inhibiting IL-33 and ST2.

Electroacupuncture preconditioning relieves cutaneous passive anaphylaxis by down-regulating IP3 mediated ROS/TRPM2 signaling pathway and inhibiting mast cell degranulation in rats with urticaria

To observe the effect of electroacupuncture (EA) preconditioning of "Quchi" (LI11) and "Xuehai" (SP10) on mast cell (MC) degranulation, and expressions of inositol triphosphate(IP3), reactive oxygen species (ROS), transient receptor potential (TRP) M2, calmodulin (CaM) in rats with urticaria, so as to reveal its molecular mechanism under-lying improving urticaria. Thirty-two male SD rats were randomly divided into blank control, model, preconditioning of EA (Pre-EA) and medication groups (n=8 rats/group). The urticaria model was established by intradermal injection of dilute allogeneic antioalbumin serum at the spots of the bilateral symmetry of the spine on the back, and followed by tail venous injection of mixture solution of egg albumin diluent, plus 0.5% Evans blue and normal saline. Ten days before the end of modeling, rats of the pre-EA group received EA stimulation of LI11 and SP10 for 20 min, once a day for 10 consecutive days, and those of the medication group received gavage of loratadine tablets diluted solution (1 mg/kg) once a day for 10 days. The times of rat's scratching the sensitized skin were recorded, the diameter of the sensitized blue spots was measured and the degranulation rate of skin MCs was counted under microscope after toluidine blue staining. The expression levels of IP3, ROS, TRPM2 and CaM in the skin tissue were measured by immunohistochemistry and western blot, respectively. Compared with the blank control group, the scratching times, diameter of the sensitized blue spots, degranulation rate of MCs, and the expression levels of ion channel related proteins (IP3, ROS, TRPM2 and CaM) were significantly increased (P<0.01) in the model group. In comparison with the model group, the scratching times, diameter of sensitized blue spot, degranulation rate of MCs, and the expression levels of IP3, ROS, TRPM2 and CaM in both pre-EA and medication groups were significantly down-regulated (P<0.01, P<0.05). No significant differences were found between Pre-EA and medication groups in down-regulating the levels of the above-mentioned 7 indexes. EA-LI11 and SP10 preconditioning can reduce the cutaneous anaphylaxis in urticaria rats, which may be related to its effects in inhibiting the degranulation of MCs, and the expression of TRP channel related proteins.

Electroacupuncture Preconditioning Alleviates Lipopolysaccharides-Induced Acute Lung Injury by Downregulating LC3-II/I and Beclin 1 Expression.

Our study aimed to investigate the effect of electroacupuncture pretreatment on the inflammatory response and expression levels of LC3-II/I and Beclin 1 using a model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). Eighteen male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (NC, n = 6), LSP modeling group (LM, n = 6), and electroacupuncture group (EA, n = 6). Rats in the EA group received electroacupuncture pretreatment at bilateral Zusanli (ST36) and Chize (LU5) points for five days (30 min each time daily, frequency; 3 Hz/15 Hz, intensity; 1 mA). Rats in the EA and LM groups were then injected with 5 mg/kg LPS (Beijing, Solarbio Company, concentration; 5 mg/mL) through the tail vein, while those in the NC group were injected with 5 mg/kg saline. The animals were sacrificed six hours after LPS or saline injection through cervical vertebrae by dislocation under deep anesthesia. Orbital blood was collected for the analysis of serum inflammatory factors including interleukin-1β (IL-1β) and transforming growth factor-β (TGF-β). The lower left lung was excised, stained with hematoxylin-eosin (HE), and subjected to histopathological analysis. The mRNA and protein expression of Beclin 1 and LC3 II/I in the lower right lung tissues were detected via RT-qPCR and Western blot analyses, respectively. The results showed that lung injury score was significantly higher in the LM group than that of the NC group (P < 0.01) and EA group (P < 0.01). The IL-1β contents were significantly decreased in the EA group (P < 0.01) than in the LM group. In contrast, the GF-β contents were increased in the EA group significantly when compared with the LM group (P < 0.01). RT-qPCR and Western blot detection showed that the relative gene expression of LC3‐II/I and Beclin 1 was significantly lower in the EA group than in the LM group (P < 0.01). However, the relative protein expression level of LC3‐II/I and Beclin 1 was slightly lower in the EA group than the in LM group (P > 0.05). These results show that electroacupuncture pretreatment reduces the inflammatory response in ALI and can protect lung tissue by inhibiting the gene and protein expression levels of LC3‐II/I and Beclin 1.

Electroacupuncture preconditioning alleviates renal injury and oxidative stress through Sirt3/MnSOD pathway in type 2 diabetic rats

To explore the protective effect and molecular mechanism of electroacupuncture (EA) preconditioning on renal injury in type 2 diabetic rats. Fifty male Wistar rats were randomly divided into control, model, EA, EA+inhibitor, and inhibitor groups, with 10 rats in each group. Diabetes model was established by high fat and high glucose diet and intraperitoneal injection of streptozotocin (40 mg/kg). EA (2 Hz, 1 mA) preconditioning was applied to "Guanyuan" (CV4), "Zhongwan" (CV12), bilateral "Zusanli" (ST36) and "Fenglong" (ST40) for 15 min, once every other day for 8 weeks. Rats of the inhibitor and EA+inhibitor groups were given intraperitoneal injection of 3-TYP (50 mg/kg) once every other day for a total of 3 times. The body weight, kidney mass, and renal index were recorded. The contents of urine microalbumin (ALB), 24 h urine 8-hydroxydeoxyguanosine (8-OHdG) and activities of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione glycine peroxidase (GSH-Px) in kidney were detected by ELISA. The activities of mitochondrial respiratory chain enzyme complex (RCCⅠ-RCCⅣ) in kidney were detected using spectrophotometric method. HE staining, Masson staining and transmission electron microscopy were used to observe the changes of renal structure. The protein and mRNA expressions of silent information regulator 3 (Sirt3), manganese superoxide dismutase (MnSOD) in kidney were detected by Western blot and quantitative real-time PCR, respectively. After modeling and compared with the control group, the contents of ALB, the renal index, activity of ROS and content of 8-OHdG, and the renal collagen volume fraction (CVF) were increased (P<0.01), while the activities of SOD, CAT and GSH-Px, RCCⅠ-RCCⅣ, and the mRNA and protein expressions of Sirt3 and MnSOD were decreased (P<0.01). After the treatment and compared with the model group, the contents of ALB, the renal index, ROS, 8-OHdG, and the CVF were decreased in the EA group(P<0.01, P<0.05), while the activities of SOD, CAT, GSH-Px, RCCⅠ-RCCⅣ, and Sirt3 and MnSOD expression levels were increased (P<0.01, P<0.05)；the RCCⅡ activity and the expression level of MnSOD mRNA were increased (P<0.05) in the EA+inhibitor group; the ALB and 8-OHdG contents and the CVF in the inhibitor group were increased (P<0.05), while the activity of SOD, and Sirt3 and MnSOD expression levels were decreased (P<0.05). In comparison with the EA group, the contents of ALB, the renal index, activities of ROS and 8-OHdG contents, and the CVF were increased (P<0.05, P<0.01), activities of SOD, CAT and GSH-Px and RCCⅠ and RCCⅡ, and the mRNA and protein expressions of Sirt3 and MnSOD were decreased (P<0.05, P<0.01) in both EA+inhibitor group and inhibitor group, whereas the activities of RCCⅢ and RCCⅣ were decreased in the inhibitor group (P<0.05). The therapeutic effect of inhibitor was notably inferior to that of EA+inhibitor in decreasing ALB and 8-OHdG contents, and CVF (P<0.01), and in up-regulating SOD and RCCⅡ activities, Sirt3 and MnSOD expression levels (P<0.01, P<0.05). EA preconditioning can increase the expressions of renal Sirt3 and MnSOD in type 2 diabetic rats, thereby reducing the oxidative stress response and protecting the kidneys.

The Effect of Electroacupuncture Preconditioning on Regional Cerebral Oxygen Saturation Levels in Elderly Patients with Diabetes.

ObjectiveThis study aimed to evaluate the effect of electroacupuncture preconditioning on regional cerebral oxygen saturation (rSO2) levels in elderly patients with diabetes.MethodsForty patients undergoing elective diabetic foot surgery were enrolled in this study. All patients were aged 65 years and above and weighed 45–75 kg. All were characterized as class II or III according to the American Society of Anesthesiologists’ physical status classification system. Patients were divided randomly into an electroacupuncture group (group E) and a control group (group C); both groups comprised 20 patients. In group E, the DU20 (Baihui), DU24 (Shenting), and EX-HN1 (Sishencong) acupoints were selected for electroacupuncture 30 min prior to administering anesthesia, while in group C, patients underwent routine anesthesia without electroacupuncture. The patients in both groups were anesthetized using a sciatic nerve block. The number of cases with increased or decreased regional oxygen saturation (rSO2) compared with the baseline as well as rSO2 variability in the two groups were recorded and compared.ResultsThere was no significant difference in the preoperative rSO2 values between the two groups (54.4 ± 4.8 (L), 53.9 ± 5.2 (R) [group C] vs 54.1 ± 5.2 (L), 54.5 ± 4.6 (R)[group E]). Compared with group C, the rSO2 in group E increased (50.3 ± 3.9 [group C] vs 58.4 ± 3.2[group E]), and this difference was statistically significant (P < 0.001).ConclusionElectroacupuncture stimulation can increase rSO2 levels in patients with diabetes.Clinical Registration NumberChiCTR2100048783 (http://www.chictr.org.cn).

Effects of Electroacupuncture Preconditioning at Baihui and Zusanli Acupoints on the Expression of Inflammatory Factors in Brain and Intestines of Rats with Cerebral Ischemia/Reperfusion

<sec><title>Objective</title> To observe the effects of electroacupuncture preconditioning on the expression of interleukin-17A（IL-17A）and IL-10 in the brain and intestine of rats with cerebral ischemia/reperfusion and to explore the brain-gut protective effect of electroacupuncture preconditioning. </sec><sec><title>Methods</title> A total of 36 male Sprague-Dawley rats were randomly divided into the sham group (S-con group), the model group (M-con group), and the electroacupuncture preconditioning group (EP group) ,with 12 cases in each group. The S-con group was operated according to the model of middle cerebral artery occlusion/reperfusion (MCAO/R) with no blocking of the cerebral blood flow and reperfusion. The M-con group was given the operation of MCAO/R model and the cerebral blood perfusion was restored after 120 minutes. The EP group was intervened by electroacupuncture preconditioning at Baihui (DU20) and Zusanli (ST36) acupoints for two weeks, and was given the operation of MCAO/R model after the last electroacupuncture intervention for 24 hours, the cerebral blood perfusion was restored after 120 minutes. Before surgery for one day, after reperfusion for 12 h and after reperfusion for 1,3,7 days, the grip tester was used to measure the forelimb grasping strength; after reperfusion for 7 days, ELISA methods was used to determine the content of IL-17A and IL-10 in serum, Western blot method was used to detect the expression of IL-17A and IL-10 protein in ischemic cortex and colon tissue, immunohistochemistry method was used to calculate the average optical density (AOD) value of IL-17A and IL-10 in ischemic cortex and colon tissue, and HE staining method was used to observe the pathological change of ischemic cortex. </sec><sec><title>Results</title> ① Forelimb grasping strength: compared with the S-con group, the forelimb grasping strength of rats in the M-con group after reperfusion for 12 h, 1 d, 3 d, 7 d was decreased significantly (<italic>P</italic><0.05); compared with the M-con group, the forelimb grasping strength of rats in the EP group was increased significantly (<italic>P</italic><0.05). ② Content of IL-17A and IL-10 in serum: after reperfusion for 7 days, compared with the S-con group, the content of serum IL-17A and IL-10 of rats in the M-con group were significantly increased (<italic>P</italic><0.05); compared with the M-con group, the content of serum IL-17A in the EP group were significantly decreased (<italic>P</italic><0.05), and IL-10 in the EP group were significantly increased (<italic>P</italic><0.05). ③ Expression of IL-17A and IL-10 protein: after reperfusion for 7 days, compared with the S-con group, the expression of IL-17A and IL-10 protein in ischemic cortex and colon tissue in the M-con group were significantly increased (<italic>P</italic><0.05); compared with the M-con group, the expression of IL-17A in the EP group was significantly decreased (<italic>P</italic><0.05), and the expression of IL-10 protein in the EP group was significantly increased (<italic>P</italic><0.05). ④ AOD value of IL-17A and IL-10: after reperfusion for 7 days, compared with the S-con group, the AOD value of IL-17A and IL-10 in ischemic cortex and colon tissue in the M-con group were significantly increased (<italic>P</italic><0.05); compared with the M-con group, the AOD value of IL-17A in the EP group was significantly decreased (<italic>P</italic><0.05), the AOD value of IL-10 in the EP group was significantly increased (<italic>P</italic><0.05). ⑤ Pathological change of ischemic cortex: after reperfusion for 7 days, compared with the M-con group, the pathological change of ischemic cortex in EP group was significantly decreased (<italic>P</italic><0.05). </sec><sec><title>Conclusion</title> Electroacupuncture preconditioning at Baihui and Zusanli acupoints can reduce the pathological damage degree of the ischemic cortex and intestinal-central inflammation, improve neurobehavioral function, which may be related to brain-gut protection. </sec>

Electroacupuncture Preconditioning Reduces Oxidative Stress in the Acute Phase of Cerebral Ischemia-Reperfusion in Rats by Regulating Iron Metabolism Pathways.

Background Oxidative stress is an important mechanism of cerebral ischemia-reperfusion injury. Ferroptosis caused by iron overload after cerebral ischemia-reperfusion is considered a common cause of oxidative stress. Many recent studies have shown that electroacupuncture (EA) can regulate the expression of inflammatory factors, and the use of electroacupuncture preconditioning can produce a protective effect, which can reduce injury after cerebral ischemia and reperfusion. We aimed to assess whether EA could be used to reduce oxidative stress. Methods The oxidative stress level of rats during the acute phase of cerebral ischemia and reperfusion was assessed with and without preconditioning with EA. Molecular biology methods were used to detect iron metabolism and oxidative stress-related proteins. Results Rats that had EA preconditioning had lower infarct volumes than rats in the control group. Furthermore, western blot analysis showed that the expression of iron metabolism-related protein FPN-1 was higher in the intervention group than in the model group after reperfusion. In this regard, further investigation also demonstrated higher expression of glutathione and glutathione peroxidase-4, and lower reactive oxygen species values in the brain tissue of the EA group were compared with those of the control group rats. Conclusions Electroacupuncture preconditioning can reduce oxidative stress after cerebral ischemia-reperfusion by regulating iron overload.

Effect of electroacupuncture preconditioning on neuronal activities in lateral hypothalamus area of myocardial ischemia reperfusion injury rats

To observe the effect of electroacupuncture (EA) preconditioning of "Shenmen" (HT7)-"Tongli" (HT5) segment of the Heart Meridian on neuronal electrical activities of lateral hypothalamus area (LHA) in rats with myocardial ischemia reperfusion injury (MIRI), so as to investigate its possible mechanism underlying improvement of MIRI. Twenty-four SD rats were randomly divided into sham, model, EA and damage + EA (D+EA) groups, with 6 rats in each group. The MIRI model was established by occlusion of the anterior descending branch (ADB) of the left coronary artery for 30 min, followed by reperfusion for 2 h. In the sham operation group, the ADB was only threaded beneath the artery without ligation. EA (2 Hz, 1 V) was applied to bilateral HT7-HT5 for 20 min, once daily for 7 days. In the D+EA group, FN was injected with 0.4 μL of 1 g/L kainic acid solution. Electrocardiogram (ECG) of the neck-thoracic lead was recorded by using PowerLab. The electrical activities of the LHA region were recorded by the implanted microelectrode array (2×4) and Plexon multi-channel acquisition system. Cluster analysis of neuronal signals was carried out by Offline Sorter software. The discharge waveforms, autocorrelation and cross-correlation of neuronal activities were analyzed by using Neuro Explorer software. Compared with the sham group, the ECG-ST height was significantly increased (P<0.05), the discharge frequency of pyramidal neurons was significantly reduced (P<0.01), while the discharge frequency of interneurons was increased (P<0.01) in the model group. After EA treatment, the ECG-ST height was significantly decreased (P<0.05), the discharge frequency of pyramidal neurons was significantly increased (P<0.01) relevant to the model group. In comparison with the EA group, the ECG-ST height in the D+EA group was significantly elevated (P<0.05), whereas the discharge frequency of pyramidal neurons was significantly decreased (P<0.01). The discharge frequency of interneurons was kept increasing after MIRI. Real-time spectrum analysis showed that the local field potential spectrum energy of the EA group was significantly lower than that of the model group and the D+EA group. EA preconditioning of Heart Meridian can significantly increase the discharge frequency of LHA excitatory pyramidal neurons and reduce the energy of the local field potential spectrum, which maybe one of the important mechanisms of EA in anti -MIRI.

Effect of Electroacupuncture Preconditioning on Inflammatory Factors of Rabbits after Spinal Cord Ischemia-Reperfusion Injury

Effect of Electroacupuncture Preconditioning on Inflammatory Factors of Rabbits after Spinal Cord Ischemia-Reperfusion Injury

Effect of electroacupuncture preconditioning of "Neiguan"(PC6) on myocardial LKB1/AMPK/PFK2 pathway in myocardial ischemia rats

To observe the effect of electroacupuncture (EA) preconditioning on the expression of liver protein kinase 1 (LKB1), adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and 6-phosphofructo-2-kinase (PFK2) in cardiomyocytes of rats with acute myocardial ischemia (AMI), so as to explore its mechanisms underlying cardioprotective effect. Thirty male Wistar rats were randomly divided into sham-operation, model and EA pretreatment groups (n＝10 rats per group). The AMI model was established by ligation of the left anterior descending branch of coronary artery. Before modeling, EA preconditioning (2 Hz/15 Hz, 1 mA) was applied to bilateral "Neiguan"(PC6) for 30 min, once daily for 14 days. Histopathological changes of myocardium was observed by microscope after H．E. staining. The level of lactate dehydrogenase (LDH) in serum was detected by ELISA. The expression of autophagy-associated proteins and mRNAs as LKB1, AMPKa1, AMPKa2 and PFK2 were detected by Western blot and real-time PCR, respectively. Compared with the sham-operation group, serum LDH content, and expression levels of myocardial AMPKa2 and PFK2 proteins and mRNAs were significantly up-regulated (P<0.01), and those of LKB1 and AMPKa1 proteins and mRNAs were increased in the model group (P<0.05). Following the intervention, serum LDH were apparently down-regulated (P<0.01), and expression levels of myocardial LKB1, AMPKa1 and PFK2 proteins and mRNAs were apparently up-regulated (P<0.01), but that of AMPKa2 protein and mRNA was remarkably down-regulated in the EA group (P<0.01). H．E. staining showed cell swelling, disordered arrangement of myocardial fibers with obvious rupture, interstitial bleeding and inflammatory infiltration, which was relatively milder in the EA preconditioning group. EA pretreatment can trigger LKB1/AMPK/PFK2 signaling pathway in AMI rats, which may contribute to its cardioprotective effect against ischemic myocardial injury by activating autophagy of cardiomyocytes. .

Development of research on mechanisms of electroacupuncture intervention underlying improvement of cerebral ischemia rats in recent five years

In the present paper, we summarized the relevant research literature on the underlying mechanism of electroacupuncture (EA) intervention in improving cerebral ischemia (CI) in middle cerebral artery occlusion (MCAO) model rats in recent 5 years from preconditioning and regular intervention. Outcomes showed that both EA preconditioning and regular intervention could relieve CI by reducing toxicity of excitatory amino acids (glutamate, aspartate) and TLR4/NF-κB-mediated inflammatory cascade reaction to relieve inflammatory injury. Moreover, EA preconditioning also could suppress the expression of pro-apoptosis genes and proteins to relieve apoptosis, regulate activation of microglia, and down-regulate the expression of blood brain barrier integrity-related matrix metalloprotein 9. Regular EA intervention also could promote angiogenesis to increase supply of blood and oxygen, facilitate regeneration, proliferation and differentiation of neural stem cells via triggering activation of Notch and Shh signaling pathways, and promote the secretion of neurotrophin by up-regulating the expression of brain derived neurotrophic factor and nerve growth factor /Trk A receptor, and promote expression of axon growth and synaptic remodeling-related factor (Ephrin B2/Eph B2) and sr-GTPase activating protein 1 and cell division cycle 42 (Cdc42, axon growth and orientated down-stream molecules). However, up to now, the conclusion is still fragmentary and one-sided, and can not explain the specific mechanism of electroacupuncture in MCAO rats, needing further in-depth study.

Effect of "Jiaji" (EX-B2)-electroacupuncture preconditioning on expression of myocardial cytochrome P450 enzyme in rats with acute myocardial ischemia-reperfusion injury

To investigate the effect of "Jiaji"(EX-B2)-electroacupuncture(EA) preconditioning on structural changes of myocardium and expression of cytochrome P450 (CYP450) enzymes in acute myocardial ischemia-reperfusion injury (MIRI) rats. Sixty male Wistar rats were randomly divided into sham operation, model, EX-B2, Neiguan (PC6), Yanglingquan(GB34) and Quchi (LI11) groups (n＝10 in each group). The MIRI model was established by occlusion of the descending anterior branch of the left coronary artery for 30 min, followed by reperfusion for 30 min. EA preconditioning (2 Hz/100 Hz, 1 mA) was respectively applied to EX-B2, PC6, GB34, and LI11 for 30 min, once daily for 7 days. Morphological changes of myocardium were observed by H．E. staining. The ultrastructure of myocardial cells was observed by transmission electron microscope (TEM). The protein expression levels of myocardial CYP450 (CYP1A1, CYP2B2, CYP2C11 and CYP4A2) were detected by Western blot. In MIRI rats, myocardial pathological changes as swollen, disorganized arrangement, and partially ruptured myocardial fibers with unclear limit and necrosis and infiltration of lots of inflammatory cells under microscope, and focal myofilament degeneration, dissolution and necrosis with interstitial edema, vague mitochondria with swelling and vacuolation, ruptured and disorganized arrangement of crests under TEM were found in the ischemic area, which was obviously milder in rats of both EX-B2 and PC6 groups. After modeling, the expression of myocardial CYP1A1 and CYP2B2 protein were significantly up-regulated in the model group relevant to the sham operation group (P<0.05). In EA preconditioning groups, the expression levels of CYP1A1 and CYP4A2 proteins in the EX-B2, PC6 and GB34 groups were obviously down-regulated (P<0.01), and those of CYP2B2 and CYP2C11 proteins in both EX-B2 and PC6 groups were markedly up-regulated relevant to the model group (P<0.01). Compared with the EX-B2 group, the expression levels of CYP1A1, CYP4A2 proteins in the LI11 group were significantly up-regulated (P<0.05), and CYP2B2, CYP2C11 proteins were significantly down-regulated (P<0.05). No significant differences were found between the model and sham operation groups in the expression levels of myocardial CYP2C11 and CYP4A2 proteins, between the LI11 and model groups in the expression of CYP1A1, CYP2B2, CYP2C11 and CYP4A2, between the GB34 and model groups in the expression of CYP2B2, CYP2C11 (all P>0.05)．. EA preconditioning at EX-B2 and PC6 can suppress MIRI induced up-regulation of myocardial CYP450 ω-hydroxylase CYP1A1 and CYP4A2 expression and further up-regulate the expression of myocardial epoxygenase CYP2B2 and CYP2C11 proteins in acute MIRI rats, thus playing a role in myocardial protection.

Serum metabolic profile involving protective effect of "Neiguan"(PC6)-electroacupuncture preconditioning in rats with myocardial ischemia reperfusion injury

To observe the effect of "Neiguan" (PC6)-electroacupuncture (EA) preconditioning on serum metabolites in myocardial ischemia-reperfusion injury (MIRI) rats, so as to reveal its mechanism underlying improvement of ischemic myocardium from metabonomics. A total of 48 male SD rats were randomly divided into control, model, EA "Neiguan"(PC6) and EA "Hegu"(LI4) groups (n＝12 rats/ group). Rats of the control group were just banded on animal boards for 30 min, once daily for 7 days. The MIRI model was established by occlusion of the left anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 1 h, and rats of the model group were also banded as those in the control group. Before modeling, EA (10 Hz/50 Hz, 1 mA) was applied to bilateral "Neiguan"(PC6) and "Hegu"(LI4) for 30 min, once daily for 7 successive days. After the treatment, serum samples were collected to be analyzed by proton nuclear magnetic resonance (1H NMR) spectroscopy. The orthogonal partial least squares discriminate analysis (PLS-DA) was employed to distinguish the serum differential metabolic profile of rats in different groups and identify potential biomarkers. After modeling, the ECG of model group and electroacupuncture groups showed T wave towering, and there was no obvious ST segment between R wave and T wave. The T wave decreased more than 0.2 mV after reperfusion, and there was no obvious ST segment. Compared with the control group, MIRI induced significant changes of metabolites in the serum including increase of acetoacetate acid, lectic acid, creatine, glycerol and glucose, and decrease of alanine, glutamine, glycerophosphoryl choline and phosphorylcholine. In comparison with the model group, PC6-EA preconditioning induced significant changes, including an increase of glucose, and a decrease of leucine，isoleucine, valine，3-hydroxybutyric acid，lactate，acetate，acetone，acetoacetate acid，pyruvic acid，glutamine，creatine and glycerol. There is no significant difference in metabolic patterns between "Hegu" group and model group. Metabolic pathway enrichment analysis indicated that the protective effect of PC6-EA pretreatment was realized mainly by regulating pathways of glycolysis, gluconeogenesis, citric acid metabolism, pyruvate metabolism, ketone body metabolism, etc. PC6-EA pretreatment has a role in regulating gluconeogenesis, pyruvate metabolism, amino metabolism, ketone body metabolism and energy metabolism in rats with MIRI, which maybe contribute to its protective effect on ischemic myocardium, but the specific metabolic pathways and mechanisms need being studied further.

Effect of Electroacupuncture at "Shenmen" (HT 7)- "Tongli" (HT 5) of Heart Meridian on Neuronal Activities in Paraventricular Nucleus of Hypothalamus in Myocardial Ischemia Rats

To observe the effect of electroacupuncture (EA) stimulation of "Shenmen" (HT 7) - "Tongli" (HT 5) segment of the Heart Meridian on neuronal electrical activities of hypothalamic paraventricular nucleus (PVN) in rats with myocardial ischemia (MI), so as to investigate its possible mechanism underlying improvement of MI. Thirty-two SD rats were randomly divided into sham control, model, HT 7-HT 5 and "Taiyuan" (LU 9)- "Lieque" (LU 7) groups (n=8 in each group). EA preconditioning (2 Hz, 1 V, 20 min) was applied to bilateral HT 7-HT 5 and bilateral LU 9-LU 7, respectively, once everyday for 7 days. The electrical activities of the right PVN region were recorded by the implanted microelectrode array(2×4)and Plexon multi-channel acquisition system. Cluster analysis of neuronal signals was carried out by Offline Sorter software. The discharge waveforms, autocorrelation and cross-correlation of neuronal activities were analyzed by using Neuro Explorer software. Cluster analysis of neuronal signals showed that 2, 2, 1 and 1 interneuron in the sham, model, HT 7-HT 5, and LU 9-LU 7 groups, and 3 pyramidal neurons in the HT 7-HT 5 were acquired. Cross correlation analysis showed that the SPK 02 a and SPK 02 b neurons of the HT 7-HT 5 group had an inhibitory relationship. The total discharge frequency was significantly increased in the model group relevant to the sham group (P<0.01), and was markedly lower in the HT 7-HT 5 group than in the model group and LU 9-LU 7 group (P<0.01). Real-time spectrum analysis showed that the local field potential spectrum energy of the HT 7-HT 5 group was significantly lower than that of the model group and the LU 9-LU 7 group. EA of HT 7-HT 5 segment of the Heart Meridian can inhibit the electrical activity of interneuron and activate the electrical activity of pyramidal neuron in PVN region, and an inhibitory relationship exists between the interneuron and pyramidal neuron in MI rats, which may be a mechanism of EA in regulating activities of the ischemic heart.