Electroacupuncture ameliorates post-stroke learning and memory through minimizing ultrastructural brain damage and inhibiting the expression of MMP-2 and MMP-9 in cerebral ischemia-reperfusion injured rats

Coenzyme Q10 and exercise training reinstate middle cerebral artery occlusion-induced behavioral deficits and hippocampal long-term potentiation suppression in aging rats

RATIONAL

Patients experience post-stroke cognitive impairment during aging. To date, no specific treatment solution has been reported for this disorder.

OBJECTIVE

The purpose of this study was to evaluate the effects of exercise training and coenzyme Q10 supplementation on middle cerebral artery occlusion (MCAO) induced behavioral impairment, long-term potentiation inhibition and cerebral infarction size in aging rats.

METHODS

Fifty aging male rats underwent MCAO surgery and were randomly distributed in to the following groups: 1-Sham, 2- control, 3- Coenzyme Q10, 4- Exercise training and 5- Exercise training with Q10 supplementation (Ex + Q10). Aerobic training groups were allowed to run on a treadmill for 12 weeks. Q10 (50 mg/kg) was administered intragastrically by gavage. Morris water maze, shuttle box and elevated plus maze tests were used to evaluate cognitive function. The population spike (PS) amplitude and slope of excitatory postsynaptic potentials (EPSP) in the dentate gyrus area were recorded as a result of perforant pathway electrical stimulation.

RESULTS

Our study showed that Q10 and aerobic training alone ameliorate spatial memory in the acquisition phase, but have no effect on spatial memory in the retention phase. Q10 and exercise training synergistically promoted spatial memory in the retention phase. Q10 and exercise training separately and simultaneously mitigated cerebral ischemia-induced passive avoidance memory impairment in acquisition and retention phases. The EPSP did not differ between the groups, but exercise training and Q10 ameliorate the PS amplitude in hippocampal responses to perforant path stimulation. Exercising and Q10 simultaneously reduced the cerebral infarction volume.

CONCLUSION

Collectively, the findings of the present study imply that 12 weeks of aerobic training and Q10 supplementation alone can simultaneously reverse cerebral ischemia induced neurobehavioral deficits via amelioration of synaptic plasticity and a reduction in cerebral infarction volume in senescent rats.

Involvement of P2X7R-mediated microglia polarization and neuroinflammation in the response to electroacupuncture on post-stroke memory impairment

PURPOSE

Post-stroke cognitive impairment (PSCI) is a common complication of ischemic stroke episodes. Memory impairment is an important component of the poststroke cognitive syndrome. Microglial activation plays a critical role in stroke-induced neuroinflammation. Previous studies have reported that electroacupuncture (EA) provides neuroprotective effects by reducing the expression levels of the Purinergic receptor P2X ligand-gated ion channel 7 (P2X7) and inhibiting neuroinflammation in rat model of ischemic stroke. Further understanding of the role and connections between P2X7R and microglial activation in EA-induced anti-inflammatory can reveal novel targets for post-stroke memory impairment treatment.

METHODS

A Middle cerebral artery occlusion and reperfusion (MCAO/R) model was established. We used 2'(3')-O-(4-benzoyl) benzoyl ATP (BzATP) as a P2X7R agonist. Following MCAO/R injury, the rats underwent EA therapy at the Baihui (DU20) and Shenting (DU24) acupoints for seven consecutive days. The Barnes maze test was used to evaluate memory function. Following intervention, a T2 weighted images (T2WI) scan was performed to identify changes in cerebral infarction volume in MCAO/R rats. The levels of Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and Interleukin-4 (IL-4), Interleukin-10 (IL-10) in the peri-infarct hippocampal were examined by ELISA. Immunofluorescence was employed to evaluate Iba-1+ / P2X7R+, Iba-1+/ iNOS+ and Iba-1+/ Arg-1+ cell populations in the peri-infarct hippocampal DG area. The protein expression of P2X7R, Nuclear factor E2-related factor 2 (Nrf2), Recombinant nlr family, pyrin domain containing protein 3 (NLRP3), Inducible nitric oxide synthase (iNOS) and Arginase-1 (Arg-1) in the peri-infarct hippocampal were investigated using western blot assays. Besides, we also measured the levels of reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA).

RESULTS

We found EA treatment reduced inflammation and oxidative stress, which is consistent with a decrease in P2X7R expression and improved learning and memory functions. In contrast, we found BzATP enhanced inflammation and oxidative stress. Moreover, our results showed EA treatment up-regulated Nrf2, down-regulated NLRP3, and promoted microglia M2 polarization. Finally, EA-mediated positive effects were reversed by intracerebroventricular injection of BzATP, which is consistent with an increase in P2X7R expression.

CONCLUSION

EA ameliorates memory impairment in a rat model of ischemic stroke by reducing inflammation and ROS through the inhibition of P2X7R expression. In turn, this mechanism regulates Nrf2 and NLRP3 expression, suggesting EA is beneficial for ischemic stroke treatment using P2X7R as target.

Acupuncture modulates the gut microbiota in Alzheimer's disease: current evidence, challenges, and future opportunities

Alzheimer's disease, one of the most severe and common neurodegenerative diseases, has no effective cure. Therefore it is crucial to explore novel and effective therapeutic targets. The gut microbiota - brain axis has been found to play a role in Alzheimer's disease by regulating the neuro-immune and endocrine systems. At the same time, acupuncture can modulate the gut microbiota and may impact the course of Alzheimer's disease. In this Review, we discuss recent studies on the role of acupuncture on the gut microbiota as well current challenges and future opportunities of acupuncture as potential treatment for the prevention and treatment of Alzheimer's disease.

Involvement of Interleukin-1 β/Insulin-Like Growth Factor 1 in Ameliorating Effects of Electroacupuncture on Myocardial Fibrosis Induced by Essential Hypertension

OBJECTIVE

To investigate the effect of electroacupuncture (EA) at Neiguan (PC 6) on myocardial fibrosis in spontaneously hypertensive rats (SHRs), and to explore the contribution of interleukin-1 β (IL-1 β), insulin-like growth factor 1 (IGF-1), and transforming growth factor β 1 (TGF- β 1) to the effects.

METHODS

Nine 12-weeks-old Wistar Kyoto (WKY) male rats were employed as the normal group. Twenty-seven SHRs were equally randomized into SHR, SHR+EA, and SHR + sham groups. EA was applied at bilateral PC 6 once a day 30 min per day in 8 consecutive weeks. After 8-weeks EA treatment at PC 6, histopathologic changes of collagen type I (Col I), collagen type 1 (Col 1) and the levels of IGF-1, 1L-1 β, TGF- β 1, matrix metalloproteinase (MMP)-2 and MMP-9 were examined in myocardial tissure respectively.

RESULTS

After 8-weeks EA treatment at PC 6, the enhanced myocardial fibrosis in SHRs were characterized by the increased mean fluorescence intensity of Col I and Col 1 in myocardium tissue (P<0.01). All these abnormal alterations above in SHR + EA group was significantly lower compared with the SHR group (P<0.01). Meanwhile, the increased levels of IL-1 β, IGF-1, TGF-β 1 in serum or myocardial tissue of SHRs, diminished MMP 9 mRNA expression in SHRs were also markedly inhibited after 8 weeks of EA treatment (P<0.05 or P<0.01). Furthermore, the contents of IL-1 β, IGF-1, TGF-β 1 in myocardial tissue were positively correlated with the systolic blood pressure and hydroxyproline respectively (P<0.01).

CONCLUSION

EA at bilateral PC 6 could ameliorate cardiac fibrosis in SHRs, which might be mediated by regulation of 1L-1 β/IGF-1-TGF- β 1-MMP9 pathway.

Combination of stem cell therapy and acupuncture to treat ischemic stroke: a prospective review

Stroke is the second leading cause globally that leads to severe disability and death. Stem cell therapy has been developed over the recent years to treat stroke and diminish the mortality and disability rate of brain injuries. Acupuncture, which can activate endogenous recovery via physical stimuli, has been applied to enhance the recovery and rehabilitation of stroke patients. Attempts have been made to combine stem cell therapy and acupuncture to treat stroke patients and have shown the promising results. This prospective review will look into the possible mechanisms of stem cell therapy and acupuncture and intend to undercover the potential benefit of the combined therapy. It intends to bridge the modern emerging stem cell therapy and traditional acupuncture at cellular and molecular levels and to demonstrate the potential benefit to improve clinical outcomes.

Structure and Function of the Bestrophin family of calcium-activated chloride channels

Bestrophins are a family of calcium-activated chloride channels (CaCCs) with relevance to human physiology and a myriad of eye diseases termed "bestrophinopathies". Since the identification of bestrophins as CaCCs nearly two decades ago, extensive studies from electrophysiological and structural biology perspectives have sought to define their key channel features including calcium sensing, gating, inactivation, and anion selectivity. The initial X-ray crystallography studies on the prokaryotic homolog of Best1, Klebsiella pneumoniae (KpBest), and the Best1 homolog from Gallus gallus (chicken Best1, cBest1), laid the foundational groundwork for establishing the architecture of Best1. Recent progress utilizing single-particle cryogenic electron microscopy has further elucidated the molecular mechanism of gating in cBest1 and, separately, the structure of Best2 from Bos taurus (bovine Best2, bBest2). Meanwhile, whole-cell patch clamp, planar lipid bilayer, and other electrophysiologic analyses using these models as well as the human Best1 (hBest1) have provided ample evidence describing the functional properties of the bestrophin channels. This review seeks to consolidate these structural and functional results to paint a broad picture of the underlying mechanisms comprising the bestrophin family's structure-function relationship.

Correlation between matrix metalloproteinase-2 polymorphisms and first and recurrent atherosclerotic ischemic stroke events: a case-control study

Objective

To determine the associations between matrix metalloproteinase-2 (MMP-2, encoded by the MMP2 gene) 1306C/T and 735C/T polymorphisms and first and recurrent ischemic stroke in a Chinese population.

Methods

Patients with first and recurrent ischemic stroke were included. Serum MMP-2 was measured, and MMP2 1306C/T and 735C/T polymorphisms were detected. The associations between MMP2 1306C/T and 735C/T polymorphisms and first and recurrent ischemic stroke were analyzed.

Results

Serum MMP-2 in patients with first and recurrent ischemic stroke was significantly higher compared with controls, and patients with recurrent ischemic stroke had higher MMP-2 than those with first ischemic stroke. The frequency of the CC genotype and C allele of MMP2 735C/T was highest in patients with recurrent ischemic stroke, followed by patients with first ischemic stroke, and controls. Conversely, the genotype and allele of MMP2 1306C/T did not significantly differ between groups. The CC genotype of MMP2 735C/T was independently associated with first and recurrent ischemic stroke (odds ratios = 1.45 and 1.64, respectively), as was the C allele of MMP2 735C/T (odds ratios = 1.68 and 1.77, respectively).

Conclusions

The CC genotype and C allele of MMP2 735C/T were associated with first and recurrent ischemic stroke in a Chinese population.

Effects of Thrombin on the Neurovascular Unit in Cerebral Ischemia

Cerebral ischemia is a cerebrovascular disease with high morbidity and mortality that poses a significant burden on society and the economy. About 60% of cerebral ischemia is caused by thrombus, and the formation of thrombus proceeds from insoluble fibrin, following its transformation from liquid fibrinogen. In thrombus-induced ischemia, increased permeability of the blood-brain barrier (BBB), followed by the extravasation of blood components into the brain results in an altered brain microenvironment. Changes in the brain microenvironment affect brain function and the neurovascular unit (NVU), the working unit of the brain. Recent studies have reported that coagulation factors interact with the NVU and its components, but the specific function of this interaction is highly speculative and warrants further investigations. In this article, we reviewed the role of coagulation factors in cerebral ischemia and the role of coagulation factors in thrombosis. Additionally, the influence of thrombin on the NVU is introduced, as well as in the function of NVU, which may help to explore part of brain injury mechanism during ischemia. Lastly, we propose some novel therapeutic approaches on ischemic stroke by reducing the risk of coagulation.

Early Electroacupuncture Extends the rtPA Time Window to 6 h in a Male Rat Model of Embolic Stroke via the ERK1/2-MMP9 Pathway

Background. Recombinant tissue plasminogen activator (rtPA) is the only recommended pharmacological treatment for acute ischemic stroke, but it has a restricted therapeutic time window. When administered at time points greater than 4.5 h after stroke onset, rtPA disrupts the blood-brain barrier (BBB), which leads to serious brain edema and hemorrhagic transformation. Electroacupuncture (EA) exerts a neuroprotective effect on cerebral ischemia; however, researchers have not clearly determined whether EA increases the safety of thrombolysis and extends the therapeutic time window of rtPA administration following ischemic stroke. Objective. The present study was conducted to test the hypothesis that EA extends the therapeutic time window of rtPA for ischemic stroke in a male rat model of embolic stroke. Methods. SD rats were randomly divided into the sham operation group, model group, rtPA group, EA+rtPA group, and rtPA+MEK1/2 inhibitor group. An injection of rtPA was administered 6 h after ischemia. Rats were treated with EA at the Shuigou (GV26) and Neiguan (PC6) acupoints at 2 h after ischemia. Neurological function, infarct volume, BBB permeability, brain edema, and hemorrhagic transformation were assessed at 24 h after ischemia. Western blotting and immunofluorescence staining were performed to detect the levels of proteins involved in the ERK1/2 signaling pathway (MEK1/2 and ERK1/2), tight junction proteins (Claudin5 and ZO-1), and MMP9 in the ischemic penumbra at 24 h after stroke. Results. Delayed rtPA treatment aggravated hemorrhagic transformation and brain edema. However, treatment with EA plus rtPA significantly improved neurological function and reduced the infarct volume, hemorrhagic transformation, brain edema, and EB leakage in rats compared with rtPA alone. EA increased the levels of tight junction proteins, inhibited the activation of the ERK1/2 signaling pathway, and reduced MMP9 overexpression induced by delayed rtPA thrombolysis. Conclusions. EA potentially represents an effective adjunct method to increase the safety of thrombolytic therapy and extend the therapeutic time window of rtPA administration following ischemic stroke. This neuroprotective effect may be mediated by the inhibition of the ERK1/2-MMP9 pathway and alleviation of the destruction of the BBB.

Effectiveness of theta and gamma electroacupuncture for post-stroke patients on working memory and electrophysiology: study protocol for a double-center, randomized, patient- and assessor-blinded, sham-controlled, parallel, clinical trial

BACKGROUND

Practitioners of complementary and alternative medicine have suggested that electroacupuncture (EA) could improve post-stroke cognitive impairment, based on the clinical evidence. This study protocol is aimed at showing the effectiveness of theta and gamma EA for post-stroke patients on working memory (WM) and electrophysiology.

METHODS

After assessing their eligibility, 66 patients with stroke will be enrolled from two Chinese medicine hospitals and randomly divided into theta frequency EA group, gamma frequency EA group, and sham-EA group according to the ratio of 1:1:1. All patients will receive 20 sessions of EA procedures for 4 weeks. Patients in three groups will receive EA at two same acupoints in the head: Baihui (GV20) and Shenting (GV24). The frequency of the three groups of EA is set as follows: 6 Hz (theta-EA group), 40 Hz (gamma-EA group), and no current through the electrodes (sham EA). Patients and assessors will be blinded throughout the entire study. The primary outcome is the performance accuracy of 1-back task which is a frequently used measure of WM in cognitive neuroscience research contexts. Secondary outcome measures will include the response time of 1-back task, the Rivermead Behavioral Memory Test, Trail Making Test, Loewenstein Occupational Therapy Cognitive Assessment Scale, modified Barthel Index, and electroencephalogram (EEG) signals during 1-back tasks. A blinding index will be assessed. Data will be statistically analyzed by one-way ANOVA, at 5% of significance level.

DISCUSSION

We expect this double-center, randomized, patient- and assessor-blinded, sham-controlled, parallel, clinical trial to explore the effectiveness of theta and gamma EA therapy, compared with sham EA, for post-stroke WM.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2000031995 . Registered on 17 April 2020.

Disease Stage-Associated Alterations in Learning and Memory through the Electroacupuncture Modulation of the Cortical Microglial M1/M2 Polarization in Mice with Alzheimer's Disease

Microglia are the primary cells that exert immune function in the central nervous system, and accumulating evidence suggests that microglia act as critical players in the initiation of neurodegenerative disorders, such as Alzheimer's disease (AD). Microglia seemingly demonstrate two contradictory phenotypes in response to different microenvironmental cues, the M1 phenotype and the M2 phenotype, which are detrimental and beneficial to pathogenesis, respectively. Inhibiting the M1 phenotype with simultaneous promoting the M2 phenotype has been suggested as a potential therapeutic approach for cure AD. In this study, we demonstrated that electroacupuncture at the Shenting and Baihui acupoints for 16 weeks could improve learning and memory in the Morris water maze test and reduce amyloid β-protein in the parietal association cortex and entorhinal cortex in mice with mild and moderate AD. Besides, electroacupuncture at the Shenting and Baihui acupoints not only suppressed M1 marker (iNOS/IL-1β) expression but also increased the M2 marker (CD206/Arg1) expression in those regions. We propose that electroacupuncture at the Shenting and Baihui acupoints could regulate microglial polarization and decrease Aβ plaques to improve learning and memory in mild AD mice.

Antihypertensive and Antifibrosis Effects of Acupuncture at PC6 Acupoints in Spontaneously Hypertensive Rats and the Underlying Mechanisms

Long-term hypertension can lead to both structural and functional impairments of the myocardium. Reversing left ventricular (LV) myocardial fibrosis has been considered as a key goal for curing chronic hypertension and has been a hot field of research in recent years. The aim of the present work is to investigate the effect of electroacupuncture (EA) at PC6 on hypertension-induced myocardial fibrosis in spontaneously hypertensive rats (SHRs). Thirty SHRs were randomized into model, SHR + EA, and SHR + Sham EA groups with WKY rats as a normal control. EA was applied once a day for 8 consecutive weeks. The cardiac fibrosis as well as the underlying mechanisms were investigated. After 8 weeks of EA treatment at PC6, the enhanced myocardial fibrosis in SHRs was characterized by an increased ratio of left ventricular mass index (LVMI), collagen volume fraction (CVF), and elevated content of hydroxyproline (Hyp) as well as the upregulated expression of collagen I and collagen III in myocardium tissue of SHRs. All these abnormal alterations in the SHR + EA group were significantly lower compared to the model group. In addition, EA at PC6 significantly improved the pathological changes of myocardial morphology. Meanwhile, the increased levels of angiotensin II (Ang II) and tumor necrosis factor-α (TNFα) and expression of transforming growth factor β1 (TGF-β1), connective tissue growth factor (CTGF), matrix metalloproteinase (MMP)-2, and MMP-9 in the serum or heart tissue of SHRs were also markedly diminished by EA. These results suggest that EA at bilateral PC6 could ameliorate cardiac fibrosis in SHRs, which might be mediated by the regulation of the Ang II – TGF-β₁ pathway.

1-Trifluoromethoxyphenyl-3-(1-Propionylpiperidin-4-yl) Urea Protects the Blood-Brain Barrier Against Ischemic Injury by Upregulating Tight Junction Protein Expression, Mitigating Apoptosis and Inflammation In Vivo and In Vitro Model

We previously have revealed that 1-trifluoromethoxyphenyl-3-(1- propionylpiperidin-4-yl) urea (TPPU), as a soluble epoxide hydrolase (sEH) inhibitor can reduce infarct volume, protect blood-brain barrier (BBB) and brain against ischemic injury in rats. Here, we investigated the potential mechanisms of TPPU on BBB integrity in both in permanent middle cerebral artery occlusion (pMCAO) rat model and in oxygen-glucose deprivation/reperfusion (OGD/R)-induced human brain microvascular endothelial cells (HBMVECs) model. In pMCAO rat, TPPU administration decreased brain edema and Evans blue content, increased tight junction proteins (TJs) expression of claudin-5, occludin, and zonula occludens-1 (ZO-1). In OGD/R model, OGD/R significantly increased permeability and cell apoptosis, downregulated the expression of claudin-5, ZO-1, occludin, and lymphoma (Bcl)-2. Notably, TPPU pretreatment effectively protected the BBB integrity by reducing the permeability, promoting expression of claudin-5, ZO-1, occluding and Bcl-2, mitigating reactive oxygen species (ROS) injury and release of interleukin-1β (IL-1β), IL-6β, and tumor necrosis factor-α (TNF-α), downregulating expression of matrix metalloproteinase-9 (MMP-9), MMP-2, bcl-2-associated X protein (Bax), IL-1β, IL-6β, and TNF-α. Moreover, OGD/R induced the up-regulation of p-p65, p-IκB, and p-p38, which were effectively decreased after TPPU pretreatment in comparison with that of the OGD/R group. Furthermore, pyrrolidinedithiocarbamate (PDTC, a selective inhibitor of NF-κB p65) not only alleviated the OGD/R-induced HBMVECs injury and permeability, but also reduced the expression of TNF-α, IL-6, IL-1β, p-p65, and p-IκB, and the protective effect of PDTC was equivalent to that of TPPU. These results indicate that TPPU protects BBB integrity against ischemic injury by multiple protective mechanisms, at least in part, by reducing ROS, inflammation, apoptosis, and suppressing the nuclear factor-κB (NF-κB) and p38 signaling pathways.

Zafirlukast protects blood-brain barrier integrity from ischemic brain injury

Stroke has been considered the second leading cause of death worldwide, and ischemic stroke accounts for the vast majority of stroke cases. Some of the main features of ischemic stroke are increased brain permeability, ischemia/reperfusion injury, oxidative stress, and acute inflammation. Antagonism of cysLT1R has been shown to provide cardiovascular and neural benefits. In the present study, we investigated the effects of the cysLT1R antagonist zafirlukast both in vivo and in vitro using a middle cerebral artery occlusion (MCAO) mouse model and human brain microvascular endothelial cells (HBMVECs). In vivo, we found that zafirlukast pretreatment could reduce MCAO-induced increased brain permeability by rescuing the expression levels of the tight junction proteins occludin and ZO-1. In vitro, we found that zafirlukast could suppress the increase in endothelial monolayer permeability induced by OGD/R via rescue of occludin and ZO-1 expression; additionally, we found that zafirlukast prevented OGD/R-induced degradation of the extracellular matrix via inhibition of MMP-2 and MMP-9 expression. Finally, we found that zafirlukast could also inhibit OGD/R-induced activation of the critical proinflammatory regulator NF-κB by preventing phosphorylation and nuclear translocation of p65 protein. Together, our findings demonstrate a promising role for zafirlukast in preventing damage induced by ischemic stroke and reperfusion injury.

Relationship between the matrix metalloproteinase-9 gene polymorphisms and ischemic stroke

BACKGROUND

In recent years, with the further research of human genome scanning, the relationship between matrix metalloproteinase-9 (MMP-9) gene polymorphisms and many diseases has aroused increased attention. But there is little research on the relationship between MMP-9 gene polymorphisms and ischemic stroke (IS). This study was conducted to evaluate the relationships between the rs3918242 and rs17577 polymorphisms in the MMP-9 gene and IS in a Chinese population.

METHODS

152 cases of IS patients and 152 healthy controls were enrolled in this study. All subjects were genotyped for the MMP-9 rs3918242 and rs17577 polymorphisms by polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism (RFLP) and restriction analysis.

RESULTS

Rs3918242 showed genotypes TT, TC, and CC, and rs17577 exhibited genotypes AA, AG, and GG. The MMP-9 polymorphisms rs3918242 and rs17577 exhibited complete linkage. Our study found there was no significant difference in genotype and allele between rs3918242 and rs17577 between patients and controls. The MMP-9 gene rs3918242 and rs17577 polymorphisms are not significantly correlated with IS risk. Genetic polymorphisms vary among ethnic and regional populations.

CONCLUSION

Our results suggest that MMP-9 rs3918242 is completely linked to rs17577, while the rs3918242 and rs17577 polymorphisms are not significantly associated with the risk of IS. Genetic polymorphisms vary among ethnic and regional populations.

Combined Effects of Electroacupuncture and Behavioral Training on Learning-Memory Ability and Event-Related Potential P300 in Rats with Mid/Advanced Cerebral Infarction

Background:

The effectiveness of the combination of electroacupuncture (EA) and behavioral training (BT) for mid/advanced cerebral infarction (M/ACI) and related mechanisms remains unclear. This study aimed to investigate the combined effects on the learning-memory ability and event-related potential P300 in rats with M/ACI.

Methods:

Eighty rats with M/ACI were divided into Group Model (M), Group EA, Group BT, and Group EA-BT (n = 20) according to the random number with five healthy rats in Group Control (CON). On the 6^th week after modeling, EA, BT, and EA-BT were given to Group EA, Group BT, and Group EA-BT, respectively, whereas Group M and Group CON were not given any intervention. Y-maze test and P300 were recorded before and after the intervention.

Results:

After intervention, the P300 latency was lower and the amplitude was higher in the Group EA-BT, Group EA, and Group BT than before (for latency, t = −7.638, −4.334, and −5.916; for amplitude, t = 8.125, 3.846, and 5.238; P < 0.01), with Group EA-BT superior to Group EA (for latency, t = −3.708; for amplitude, t = 3.653; P < 0.01) and Group BT (for latency, t = −2.067; for amplitude, t = 2.816; P < 0.05), with no significant difference between Group BT and EA (for latency, t = −1.439; for amplitude, t = 1.075; P > 0.05). While the performances of Y-maze tests in the Group EA-BT, Group EA, and Group BT were all better than before (t = 10.359, 4.520, and 7.791, P < 0.01), with Group EA-BT better than Group EA (t = 5.627, P < 0.01) and Group BT (t = 2.913, P < 0.01) respectively, and Group BT better than Group EA (t = 2.912, P < 0.01).

Conclusion:

EA or BT can affect P300 in rats with M/ACI, and the combination of these two methods can significantly improve the learning-memory ability.

Acupuncture at ST36 exerts neuroprotective effects via inhibition of reactive astrogliosis in infantile rats with hydrocephalus

BACKGROUND

Acupuncture has been associated with improved cerebral circulation, analgesia, neuromodulatory function and neurogenesis. In particular, acupuncture at ST36 has been widely used in several central nervous system (CNS) disorders, including neurodegenerative diseases. However, its effects on hydrocephalus have not been studied. Our aim was to evaluate the effects of acupuncture at ST36 on behaviour, motor development and reactive astrogliosis in infantile rats with hydrocephalus.

METHODS

Hydrocephalus was induced in sixteen 7-day-old pup rats by injection of 20% kaolin into the cisterna magna. One day after hydrocephalus induction, acupuncture was applied once daily (for 30 min) for a total of 21 days in eight randomly selected animals (HAc group) while the remaining eight remained untreated (H group). An additional eight healthy animals were included as controls (C group). All animals were weighed daily and, from the fifth day after hydrocephalus induction, underwent MRI to determine the ventricular ratio (VR). Rats were also exposed to modified open-field tests every 3 days until the end of the experiment. After 21 days all the animals were euthanased and their brains removed for histology and immunohistochemistry.

RESULTS

Hydrocephalic rats showed an increase in VR when compared with control rats (P<0.01). In addition, these animals exhibited delayed weight gain, which was attenuated with acupuncture treatment. Hydrocephalic animals treated with acupuncture performed better in open field tests (P<0.05), and had a reduction in reactive astrocyte cell density in the corpus callosum and external capsule, as assessed by GFAP (glial fibrillary acidic protein) immunohistochemistry (P<0.05).

CONCLUSIONS

These findings indicate that acupuncture at ST36 has a neuroprotective potential mediated, in part, by inhibition of astrogliosis.

Possible Involvement of PTEN Signaling Pathway in the Anti-apoptotic Effect of Electroacupuncture Following Ischemic Stroke in Rats

As a traditional therapeutic method, electroacupuncture (EA) has been adopted as an alternative therapy for stroke recovery. Here, we aimed to evaluate whether EA therapy at points of Quchi (LI11) and Zusanli (ST36) alleviated neuronal apoptosis by PTEN signaling pathway after ischemic stroke. A total of 72 male Sprague-Dawley rats were randomized into three groups, including sham group, MCAO group, and EA group. EA was initiated after 24 h of reperfusion for 3 consecutive days. At 72 h following ischemia/reperfusion, neurological deficits, infarct volumes, and TUNEL staining were evaluated and the PTEN pathway-related proteins together with apoptosis-related proteins were detected. The results indicated that EA treatment significantly decreased cerebral infarct volume, neurological deficits and alleviated proportion of apoptotic cells in cerebral ischemic rats. Furthermore, EA significantly up-regulated the phosphorylation levels of PDK1, Akt(Thr308), GSK-3β, and down-regulated the phosphorylation levels of PTEN, Akt(Ser473) in the peri-infarct cortex. EA treatment significantly reduced the up-regulation of caspase-3, cleaved-caspase-3, Bim, and reversed the reduction of Bcl-2 induced by the ischemic stroke. These findings suggest that EA treatment at points of Quchi (LI11)- and Zusanli (ST36)-induced neuroprotection might involve inhibition of apoptosis via PTEN pathway.

Early BBB breakdown and subacute inflammasome activation and pyroptosis as a result of cerebral venous thrombosis

Cerebral venous thrombosis (CVT) is a rare form of cerebral stroke that causes a variety of symptoms, ranging from mild headache to severe morbidity or death in the more severe forms. The use of anti-coagulant or thrombolytic agents is the classical treatment for CVT. However, the development of new therapies for the treatment of the condition has not been the focus. In this study, we aimed to analyze the pathophysiology of CVT and to identify the pathways associated with its pathology. Moreover, mechanisms that are potential drug targets were identified. Our data showed the intense activation of immune cells, particularly the microglia, along with the increase in macrophage activity and NLRP3 inflammasome activation that is indicated by NLRP3, IL-1β, and IL-18 gene and caspase-1 upregulation and cleavage as well as pyroptotic cell death. Leukocytes were observed in the brain parenchyma, indicating a role in CVT-induced inflammation. In addition, astrocytes were activated, and they induced glial scar leading to parenchymal contraction during the subacute stage and tissue loss. MMP9 was responsible primarily for the BBB breakdown after CVT and it is mainly produced by pericytes. MMP9 activation was observed before inflammatory changes, indicating that BBB breakdown is the initial driver of the pathology of CVT. These results show an inflammation driven pathophysiology of CVT that follows MMP9-mediated BBB breakdown, and identified several targets that can be targeted by pharmaceutical agents to improve the neuroinflammation that follows CVT, such as MMP9, NLRP3, and IL-1β. Some of these pharmaceutical agents are already in clinical practice or under clinical trials indicating a good potential for translating this work into patient care.

Electroacupuncture Ameliorates Cognitive Impairment and Spontaneous Low-Frequency Brain Activity in Rats with Ischemic Stroke

BACKGROUND

To evaluate whether electroacupuncture (EA) at Baihui (DU20) and Shenting (DU24) acupoints could improve cognitive function and enhance spontaneous low-frequency brain activity in rats with ischemic stroke.

METHODS

Total 36 rats were randomly divided into 3 groups-the sham surgery (Sham) group, the middle cerebral artery occlusion induced cognitive deficit (MICD) group, and the MICD with EA (MICD + EA) treatment group. The rats in MICD + EA group received EA treatment at DU20 and DU24 acupoints for 14 consecutive days after the surgery. The Morris water maze test was performed to assess the spatial learning and memory ability of the rats. Magnetic resonance imaging (MRI) was used to investigate the infarction volume and spontaneous low-frequency brain activity of each group.

RESULTS

After EA for 14 days, the learning and memory ability of the MICD rats was improved, and the brain infarction volume was reduced. Furthermore, basing on the fMRI amplitude of low-frequency fluctuation (ALFF) analysis, the decreased ALFF of the MICD rats was found in auditory cortex, cingulate gyrus, lateral nucleus group of dorsal thalamus, hippocampus, motor cortex, prelimbic cortex, retrosplenial cortex, and sensory cortex compared with the rats in sham group. However, these suppressive regions were notably attenuated after EA treatment.

CONCLUSIONS

Our results suggested that EA at DU20 and DU24 acupoints could ameliorate cognitive impairment in rats with ischemic stroke, and the protective effect of EA may attribute to reactivating the cognition-related brain regions, such as hippocampus, retrosplenial cortex, cingulate gyrus, prelimbic cortex, and sensory cortex.

The effect of different frequencies of electroacupuncture on BDNF and NGF expression in the hippocampal CA3 area of the ischemic hemisphere in cerebral ischemic rats

OBJECTIVE

The aim of this study was to observe the effects of different frequencies of electroacupuncture (EA) on expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the hippocampal CA3 region of cerebral ischemic rats.

METHODS

Middle cerebral artery occlusion was successfully introduced to simulate cerebral infarction in 48 healthy male Sprague-Dawley rats. Totally, 48 rats were randomly divided into three groups: the control group, the EA 5-Hz group, and the EA 50-Hz group, 16 in each group. The rats in the control group were placed in an ordinary cage and fed normally without any treatment. EA treatment was given at a certain frequency 24 hours after surgery in the EA 5-Hz group and EA 50-Hz group. Morris water maze test was used to measure the learning and memory abilities of rats in each group after 14-day treatment with EA. Immunohistochemical staining was used to detect the expression of BDNF- and NGF-positive cells in the ischemic hippocampal CA3 area of the rats.

RESULTS

The EA 5-Hz group and EA 50-Hz group had significantly improved learning and memory ability compared with the control group according to Morris water maze findings (P<0.05). The number of BDNF- and NGF-positive cells in the hippocampal CA3 region of the ischemic hemisphere in the 5-Hz group and 50-Hz EA group was significantly more than that in the control group after EA treatment (P<0.05), and the difference in the 50-Hz group was more obvious than that in the 5-Hz group. The difference was statistically significant (P<0.05).

CONCLUSION

EA stimulation of "Baihui" and "Dazhui" can promote the expression of BDNF and NGF in the hippocampal CA3 region of cerebral ischemic rats, and the 50-Hz EA stimulation effect is more obvious.

Electroacupuncture Suppresses the NF-κB Signaling Pathway by Upregulating Cylindromatosis to Alleviate Inflammatory Injury in Cerebral Ischemia/Reperfusion Rats

Electroacupuncture (EA) may reduce inflammatory injury by inhibiting nuclear factor-kappa B (NF-κB) signaling pathway activation after ischemic stroke. Thus, we explored temporal and spatial expression of cylindromatosis (CYLD), a negative feedback inhibitor of the NF-κB signaling pathway, to learn whether CYLD is essential for EA and reduction of inflammatory injury after focal cerebral ischemia/reperfusion. A middle cerebral artery occlusion/reperfusion (MCAO/R) model was established in male Sprague-Dawley (SD) rats and CYLD gene interference was used to investigate a potential role of neuroprotection. Rats were treated with EA (1 mA, 20 Hz for 5 min, 2 Hz for 30 min) at Baihui (GV 20), Hegu (LI 4) and Taichong (LR 3) acupoints, once daily, beginning 2 h after focal cerebral ischemia. Microglial activation and co-expression of CYLD and NF-κB were measured with immunofluorescence. Neuronal CX3CL1 expression was assayed to investigate the role of EA in the interaction between neurons and microglia via upregulation of CYLD. Then, CYLD, NF-κB p65 and p-IκBα protein expression was measured with Western blot. CYLD was mainly expressed in neurons of the peri-ischemic area after MCAO/R in rats and EA upregulated CYLD mRNA and protein from 24 to 72 h after focal cerebral ischemia/reperfusion. In addition, CYLD overexpression was positively correlated to neurobehavior and negatively connected with infarct volume and pro-inflammatory cytokines (TNF-α and IL-1β). Upregulation of CYLD by EA prevented NF-κB nuclear translocation and inhibition of neuronal CX3CL1 expression, which repressed activation of microglia. Finally, CYLD silencing significantly weakened suppression of the NF-κB signaling pathway by EA. In conclusion, upregulation of CYLD may underlie how EA could alleviate inflammatory injury after focal cerebral ischemia/reperfusion.

Anti-Inflammatory Targets for the Treatment of Reperfusion Injury in Stroke

While the mainstay of acute stroke treatment includes revascularization via recombinant tissue plasminogen activator or mechanical thrombectomy, only a minority of stroke patients are eligible for treatment, as delayed treatment can lead to worsened outcome. This worsened outcome at the experimental level has been attributed to an entity known as reperfusion injury (R/I). R/I is occurred when revascularization is delayed after critical brain and vascular injury has occurred, so that when oxygenated blood is restored, ischemic damage is increased, rather than decreased. R/I can increase lesion size and also worsen blood barrier breakdown and lead to brain edema and hemorrhage. A major mechanism underlying R/I is that of poststroke inflammation. The poststroke immune response consists of the aberrant activation of glial cell, infiltration of peripheral leukocytes, and the release of damage-associated molecular pattern (DAMP) molecules elaborated by ischemic cells of the brain. Inflammatory mediators involved in this response include cytokines, chemokines, adhesion molecules, and several immune molecule effectors such as matrix metalloproteinases-9, inducible nitric oxide synthase, nitric oxide, and reactive oxygen species. Several experimental studies over the years have characterized these molecules and have shown that their inhibition improves neurological outcome. Yet, numerous clinical studies failed to demonstrate any positive outcomes in stroke patients. However, many of these clinical trials were carried out before the routine use of revascularization therapies. In this review, we cover mechanisms of inflammation involved in R/I, therapeutic targets, and relevant experimental and clinical studies, which might stimulate renewed interest in designing clinical trials to specifically target R/I. We propose that by targeting anti-inflammatory targets in R/I as a combined therapy, it may be possible to further improve outcomes from pharmacological thrombolysis or mechanical thrombectomy.

Electroacupuncture Regulates Hippocampal Synaptic Plasticity via miR-134-Mediated LIMK1 Function in Rats with Ischemic Stroke

MircoRNAs (miRs) have been implicated in learning and memory, by regulating LIM domain kinase (LIMK1) to induce synaptic-dendritic plasticity. The study aimed to investigate whether miRNAs/LIMK1 signaling was involved in electroacupuncture- (EA-) mediated synaptic-dendritic plasticity in a rat model of middle cerebral artery occlusion induced cognitive deficit (MICD). Compared to untreatment or non-acupoint-EA treatment, EA at DU20 and DU24 acupoints could shorten escape latency and increase the frequency of crossing platform in Morris water maze test. T2-weighted imaging showed that the MICD rat brain lesions were located in cortex, hippocampus, corpus striatum, and thalamus regions and injured volumes were reduced after EA. Furthermore, we found that the density of dendritic spine and the number of synapses in the hippocampal CA1 pyramidal cells were obviously reduced at Day 14 after MICD. However, synaptic-dendritic loss could be rescued after EA. Moreover, the synaptic-dendritic plasticity was associated with increases of the total LIMK1 and phospho-LIMK1 levels in hippocampal CA1 region, wherein EA decreased the expression of miR-134, negatively regulating LIMK1 to enhance synaptic-dendritic plasticity. Therefore, miR-134-mediated LIMK1 was involved in EA-induced hippocampal synaptic plasticity, which served as a contributor to improving learning and memory during the recovery stage of ischemic stroke.