Electric Stimulation of Ear Reduces the Effect of Toll-Like Receptor 4 Signaling Pathway on Kainic Acid-Induced Epileptic Seizures in Rats

Electroacupuncture Reduces Fibromyalgia Pain via Neuronal/Microglial Inactivation and Toll-like Receptor 4 in the Mouse Brain: Precise Interpretation of Chemogenetics

Fibromyalgia (FM) is a complex, chronic, widespread pain syndrome that can cause significant health and economic burden. Emerging evidence has shown that neuroinflammation is an underlying pathological mechanism in FM. Toll-like receptors (TLRs) are key mediators of the immune system. TLR4 is expressed primarily in microglia and regulates downstream signaling pathways, such as MyD88/NF-κB and TRIF/IRF3. It remains unknown whether electroacupuncture (EA) has therapeutic benefit in attenuating FM pain and what role the TLR4 pathway may play in this effect. We compared EA with sham EA to eliminate the placebo effect due to acupuncture. We demonstrated that intermittent cold stress significantly induced an increase in mechanical and thermal FM pain in mice (mechanical: 2.48 ± 0.53 g; thermal: 5.64 ± 0.32 s). EA but not sham EA has an analgesic effect on FM mice. TLR4 and inflammatory mediator-related molecules were increased in the thalamus, medial prefrontal cortex, somatosensory cortex (SSC), and amygdala of FM mice, indicating neuroinflammation and microglial activation. These molecules were reduced by EA but not sham EA. Furthermore, a new chemogenetics method was used to precisely inhibit SSC activity that displayed an anti-nociceptive effect through the TLR4 pathway. Our results imply that the analgesic effect of EA is associated with TLR4 downregulation. We provide novel evidence that EA modulates the TLR4 signaling pathway, revealing potential therapeutic targets for FM pain.

Complementary and alternative medicine for treating epilepsy in China: A systematic review

There are about 10 million people with epilepsy (PWE) in China. In addition to therapies approved by the National Medical Products Administration, the use of complementary and alternative medicine (CAM) is prevalent in Chines PWE. These CAM therapies mainly comprise traditional Chinese medicine herbs (TCMHs), acupuncture, and music. A retrospective literature search was performed to summarize the updates of CAM in China in the past ten years, and sixty-two papers were finally included. In this following review, we listed the animal and clinical studies to summarize the antiepileptic mechanisms and clinical efficacy of CAM in Chines PWE. The main mechanisms of TCMHs and acupuncture included regulation of neurotransmitters and receptors, voltage-gated ion channels modulation, expression of apoptosis-related genes, antioxidant response, and anti-inflammation. Although there were enormous clinical studies on them, the current available clinical trials were small, short-term, heterogeneous, and had a high risk of bias. With regard to music, a few studies conducted by Chinese scholars suggested that it was beneficial for PWE as an add-on therapy, which was consistent with the results of foreign studies. Further randomized clinical trials in large populations are required to prove the effectiveness and safety of CAM.

Transcription factors are potential therapeutic targets in epilepsy

Academics generally believe that imbalance between excitation and inhibition of the nervous system is the root cause of epilepsy. However, the aetiology of epilepsy is complex, and its pathogenesis remains unclear. Many studies have shown that epilepsy is closely related to genetic factors. Additionally, the involvement of a variety of tumour‐related transcription factors in the pathogenesis of epilepsy has been confirmed, which also confirms the heredity of epilepsy. In this review, we summarize the existing research on a variety of transcription factors and epilepsy and present relevant evidence related to transcription factors that may be targets in epilepsy. This information is of great significance for revealing the in‐depth molecular and cellular mechanisms of epilepsy.

CB2R induces a protective response against epileptic seizures through ERK and p38 signaling pathways

BACKGROUND AND PURPOSE

Epilepsy is a pivotal neurological disorder characterized by the synchronous discharging of neurons to induce momentary brain dysfunction. Temporal lobe epilepsy is the most common type of epilepsy, with seizures originating from the mesial temporal lobe. The hippocampus forms part of the mesial temporal lobe and plays a significant role in epileptogenesis; it also has a vital influence on the mental development of children. In this study, we aimed to explore the effects of CB2 receptor (CB2R) activation on ERK and p38 signaling in nerve cells of a rat epilepsy model.

MATERIALS AND METHODS

We treated Sprague-Dawley rats with pilocarpine to induce an epilepsy model and treated such animals with a CB2R agonist (JWH133) alone or with a CB2R antagonist (AM630). Nissl's stain showed the neuron conditon in different groups. Western blot analyzed the level of p-ERK and p-p38.

RESULTS

JWH133 can increase the latent period of first seizure attack and decrease the Grades IV-V magnitude ratio after the termination of SE. Nissl's stain showed JWH133 protected neurons in the hippocampus while AM630 inhibited the functioning of CB2R in neurons. Western blot analysis showed that JWH133 decreased levels of p-ERK and p-p38, which is found at increased levels in the hippocampus of our epilepsy model. In contrast, AM630 inhibited the protective function of JWH133 and also enhanced levels of p-ERK and p-p38.

CONCLUSIONS

CB2R activation can induce neurons proliferation and survival through activation of ERK and p38 signaling pathways.

The association between toll-like receptor 4 (TLR4) genotyping and the risk of epilepsy in children

Background

Epilepsy is one of the most widely recognized neurological disorders; unfortunately, twenty to thirty percent of patients do not get cured from epilepsy, despite many trials of antiepileptic drug (AED) therapy. Immunotherapy may be a viable treatment strategy in a subset of epileptic patients. The association between Toll-like receptor polymorphisms and epilepsy clarifies the role of the immune system in epilepsy and its response to the drug. Thus, this study will focus on the relation between TLR4 rs1927914, rs11536858, rs1927911SNPs, and epilepsy in an Egyptian case-control study to assess their link to antiepileptic drug response.

Results

According to TLR4 rs1927914, there is a significant association between the SNP and the development of epilepsy, as CC genotype is 15.3 times more at risk for developing epilepsy than TT genotype, and CT is 11.1 times more at risk for developing epilepsy than TT. Also, patients with CC genotypes are 6.3 times more at risk for developing primary epilepsy than TT genotype.

According to rs11536858, there is a significant association between cases and control groups, as AA genotypes are found to be more at risk for developing epilepsy than GG genotypes. Also, there is a statistically significant association between clonazepam resistance and rs11536858, as p value < 0.001* with the highest frequency of TT genotypes at 4.3%.

According to rs1927911, there are no significant results between the cases and the control groups or between drug-responsive and drug resistance.

Conclusion

Possible involvement of the Toll-like receptor clarifies the importance of innate immunity in initiating seizures and making neuronal hyperexcitability. In this work, multiple significant associations between TLR SNPs and epilepsy, epileptic phenotype, and drug-resistant epilepsy have been found. More studies with bigger sample sizes and different techniques with different SNPs are recommended to find the proper immunotherapy for epilepsy instead of the treatment by antiepileptic drugs.

Effect of Acupuncture on the p38 Signaling Pathway in Several Nervous System Diseases: A Systematic Review

Acupuncture is clinically used to treat various diseases and exerts positive local and systemic effects in several nervous system diseases. Advanced molecular and clinical studies have continually attempted to decipher the mechanisms underlying these effects of acupuncture. While a growing understanding of the pathophysiology underlying several nervous system diseases shows it to be related to inflammation and impair cell regeneration after ischemic events, the relationship between the therapeutic mechanism of acupuncture and the p38 MAPK signal pathway has yet to be elucidated. This review discusses the latest advancements in the identification of the effect of acupuncture on the p38 signaling pathway in several nervous system diseases. We electronically searched databases including PubMed, Embase, and the Cochrane Library from their inception to April 2020, using the following keywords alone or in various combinations: "acupuncture", "p38 MAPK pathway", "signaling", "stress response", "inflammation", "immune", "pain", "analgesic", "cerebral ischemic injury", "epilepsy", "Alzheimer's disease", "Parkinson's disease", "dementia", "degenerative", and "homeostasis". Manual acupuncture and electroacupuncture confer positive therapeutic effects by regulating proinflammatory cytokines, ion channels, scaffold proteins, and transcription factors including TRPV1/4, Nav, BDNF, and NADMR1; consequently, p38 regulates various phenomena including cell communication, remodeling, regeneration, and gene expression. In this review article, we found the most common acupoints for the relief of nervous system disorders including GV20, GV14, ST36, ST37, and LI4. Acupuncture exhibits dual regulatory functions of activating or inhibiting different p38 MAPK pathways, contributing to an overall improvement of clinical symptoms and function in several nervous system diseases.

Ferrostatin-1 mitigates cognitive impairment of epileptic rats by inhibiting P38 MAPK activation

Evidence indicates that ferrostain-1 (Fer-1), a specific inhibitor of ferroptosis, could ameliorate cognitive dysfunction of rats with kainic acid (KA)-induced temporal lobe epilepsy (TLE) by suppressing ferroptosis processes. Recent studies suggest that P38 mitogen-activated protein kinase (MAPK) pathway could be mediated by ferroptosis processes. The activation of P38 MAPK results in cognitive impairment by suppressing the expression of synaptic plasticity-related proteins. However, it is unclear whether Fer-1 can mitigate cognitive impairment of rats with KA-induced TLE by inhibiting P38 MAPK activation. In the present study, treatment with Fer-1 blocked the activation of P38 MAPK, which resulted in an increased expression of synaptophysin (SYP) and postsynaptic density protein 95 (PSD-95) in the hippocampus of rats with KA-induced TLE, hence, ameliorating their cognitive impairment. Also, P38 MAPK activation in the hippocampus of the rats reduced the expression of both PSD-95 and SYP proteins. Treatment of the rats with SB203580, a P38 MAPK-specific inhibitor, prevented the activation of P38 MAPK, which resulted in an increase in SYP and PSD95 protein levels in the hippocampus. These results suggest that Fer-1 could mitigate the cognitive impairment by suppressing P38 MAPK activation thus restoring the expression of synaptic proteins. Ferroptosis processes might be involved in suppressing synaptic protein expression.

LncRNA-UCA1 inhibits the astrocyte activation in the temporal lobe epilepsy via regulating the JAK/STAT signaling pathway

This article aimed to reveal the mechanism of long noncoding RNA (lncRNA) urothelial cancer-associated 1 (UCA1) regulated astrocyte activation in temporal lobe epilepsy (TLE) rats via mediating the activation of the JAK/STAT signaling pathway. A model of TLE was established based on rats via kainic acid (KA) injection. All rats were divided into the Sham group (without any treatments), KA group, normal control (NC; injection with empty vector) + KA group, and UCA1 +  KA group. The Morris water maze was used to test the learning and memory ability of rats, and the expression of UCA1 in the hippocampus was determined by quantitative real time polymerase chain reaction (qRT-PCR). Surviving neurons were counted by Nissl staining, and expression levels of glial cells glial fibrillary acidic protein (GFAP), p-JAK1, and p-STAT3 and glutamate/aspartate transporter (GLAST) were analyzed by immunofluorescence and Western blot analysis. A rat model of TLE was established by intraperitoneal injection of KA. qRT-PCR and fluorescence analyses showed that UCA1 inhibited astrocyte activation in the hippocampus of epileptic rats. Meanwhile, the Morris water maze analysis indicated that UCA1 improved the learning and memory in epilepsy rats. Moreover, the Nissl staining showed that UCA1 might have a protective effect on neuronal injury induced by KA injection. Furthermore, the immunofluorescence and Western blot analysis revealed that the overexpression of UCA1 inhibited KA-induced abnormal elevation of GLAST, astrocyte activation of the JAK/STAT signaling pathway, as well as hippocampus of epilepsy rats. UCA1 inhibited hippocampal astrocyte activation and JAK/STAT/GLAST expression in TLE rats and improved the adverse reactions caused by epilepsy.

Auricular Electrical Stimulation Alleviates Headache through CGRP/COX-2/TRPV1/TRPA1 Signaling Pathways in a Nitroglycerin-Induced Migraine Rat Model

The study aimed to investigate effect of auricular electrical stimulation (ES) on migraine. Migraine was induced in rats by intraperitoneal administration of nitroglycerin (NTG, 10 mg/kg) three times. Auricular ES pretreatment was performed for five consecutive days. Migraine behaviors were observed by a video recording. Auricular ES pretreatment could reverse the decrease of the total time spent on exploratory (2619.0 ± 113.0 s vs 1581.7 ± 217.6 s, p=0.0029) and locomotor behaviors (271.3 ± 21.4 s vs 114.3 ± 19.7 s, p=0.0135) and also could reverse the increase of the total time spent on resting (19.0 ± 10.6 s vs 154.3 ± 46.5 s, p=0.0398) and grooming (369.9 ± 66.8 s vs 1302.0 ± 244.5 s, p=0.0324) behaviors. Auricular ES pretreatment could increase the frequency of rearing behaviors (38.0 ± 1.8 vs 7.7 ± 3.5, p < 0.0001) and total distance traveled (1372.0 ± 157.9 cm vs 285.3 ± 85.6 cm, p < 0.0001) and also could increase the percentage of inner zone time (6.0 ± 1.6% vs 0.4 ± 0.2%, p=0.0472). The CGRP, COX-2, TRPV1, and TRPA1 immunoreactive cells in the trigeminal ganglion increased in the NTG group compared with the control group (all p < 0.0001); this increase could, however, be reduced by auricular ES pretreatment (27.8 ± 2.6 vs 63.0 ± 4.2, p < 0.0001; 21.7 ± 1.2 vs 61.8 ± 4.0, p < 0.0001; 24.3 ± 1.0 vs 36.5 ± 1.7, p=0.0003; and 20.7 ± 1.9 vs 90.8 ± 6.5, p < 0.0001, respectively). Therefore, we suggest that auricular ES pretreatment is beneficial for the treatment of migraine and this effect is partly related to CGRP/COX-2/TRPV1/TRPA1 signaling pathways.

Consensus Paper: Experimental Neurostimulation of the Cerebellum

The cerebellum is best known for its role in controlling motor behaviors. However, recent work supports the view that it also influences non-motor behaviors. The contribution of the cerebellum towards different brain functions is underscored by its involvement in a diverse and increasing number of neurological and neuropsychiatric conditions including ataxia, dystonia, essential tremor, Parkinson's disease (PD), epilepsy, stroke, multiple sclerosis, autism spectrum disorders, dyslexia, attention deficit hyperactivity disorder (ADHD), and schizophrenia. Although there are no cures for these conditions, cerebellar stimulation is quickly gaining attention for symptomatic alleviation, as cerebellar circuitry has arisen as a promising target for invasive and non-invasive neuromodulation. This consensus paper brings together experts from the fields of neurophysiology, neurology, and neurosurgery to discuss recent efforts in using the cerebellum as a therapeutic intervention. We report on the most advanced techniques for manipulating cerebellar circuits in humans and animal models and define key hurdles and questions for moving forward.

Electrical Stimulation in the Treatment of Lymphedema and Associated Skin Ulcers

Background: Lymphedema is a disorder in which lymph accumulates in the interstitial spaces due to poor lymphatic flow resulting from hypoplasia or aplasia of the lymphatic vessels, or to morpho-functional alterations that impair lymphatic flow. Lymphedema is a debilitating condition associated initially with inflammation that then degenerates into hardening of affected tissues and the formation of ulcers on the skin of affected limbs. No definitive treatment is available. The only therapy for lymphedema consists of physiotherapy, surgery, and compression to reduce impairment, which only treats the symptoms, not the causes. A possible new therapy that could reinforce the treatment of lymphedema progression and complications is electrical stimulation (ES). Many studies underline the effects of electric currents on the different cell mechanisms associated with disease. Methods and Results: In this review, we summarize the effects of ES on the molecular and cellular processes involved in the pathophysiology of lymphedema, highlighting their therapeutic potential for edema reduction, ulcer repair, and restoration of lymphatic flow in vitro and in vivo. Conclusions: ES exerts its effect on the main stages that characterize lymphedema, from its onset to ulcer formation. There are few evidences on lymphatic models and more molecular studies are needed to understand the mechanism of action of this application in the treatment of lymphedema.

Signal Transduction Pathways of Acupuncture for Treating Some Nervous System Diseases

In this article, we review signal transduction pathways through which acupuncture treats nervous system diseases. We electronically searched the databases, including PubMed, MEDLINE, clinical Key, the Cochrane Library, and the China National Knowledge Infrastructure from their inception to December 2018 using the following MeSH headings and keywords alone or in varied combination: acupuncture, molecular, signal transduction, genetic, cerebral ischemic injury, cerebral hemorrhagic injury, stroke, epilepsy, seizure, depression, Alzheimer's disease, dementia, vascular dementia, and Parkinson's disease. Acupuncture treats nervous system diseases by increasing the brain-derived neurotrophic factor level and involves multiple signal pathways, including p38 MAPKs, Raf/MAPK/ERK 1/2, TLR4/ERK, PI3K/AKT, AC/cAMP/PKA, ASK1-JNK/p38, and downstream CREB, JNK, m-TOR, NF-κB, and Bcl-2/Bax balance. Acupuncture affects synaptic plasticity, causes an increase in neurotrophic factors, and results in neuroprotection, cell proliferation, antiapoptosis, antioxidant activity, anti-inflammation, and maintenance of the blood-brain barrier.

Application and prospects of butylphthalide for the treatment of neurologic diseases

OBJECTIVE

The 3-N-butylphthalide (NBP) comprises one of the chemical constituents of celery oil. It has a series of pharmacologic mechanisms including reconstructing microcirculation, protecting mitochondrial function, inhibiting oxidative stress, inhibiting neuronal apoptosis, etc. Based on the complex multi-targets of pharmacologic mechanisms of NBP, the clinical application of NBP is increasing and more clinical researches and animal experiments are also focused on NBP. The aim of this review was to comprehensively and systematically summarize the application of NBP on neurologic diseases and briefly summarize its application to non-neurologic diseases. Moreover, recent progress in experimental models of NBP on animals was summarized.

DATA SOURCES

Literature was collected from PubMed and Wangfang database until November 2018, using the search terms including "3-N-butylphthalide," "microcirculation," "mitochondria," "ischemic stroke," "Alzheimer disease," "vascular dementia," "Parkinson disease," "brain edema," "CO poisoning," "traumatic central nervous system injury," "autoimmune disease," "amyotrophic lateral sclerosis," "seizures," "diabetes," "diabetic cataract," and "atherosclerosis."

STUDY SELECTION

Literature was mainly derived from English articles or articles that could be obtained with English abstracts and partly derived from Chinese articles. Article type was not limited. References were also identified from the bibliographies of identified articles and the authors' files.

RESULTS

NBP has become an important adjunct for ischemic stroke. In vascular dementia, the clinical application of NBP to treat severe cognitive dysfunction syndrome caused by the hypoperfusion of brain tissue during cerebrovascular disease is also increasing. Evidence also suggests that NBP has a therapeutic effect for neurodegenerative diseases. Many animal experiments have found that it can also improve symptoms in other neurologic diseases such as epilepsy, cerebral edema, and decreased cognitive function caused by severe acute carbon monoxide poisoning. Moreover, NBP has therapeutic effects for diabetes, diabetes-induced cataracts, and non-neurologic diseases such as atherosclerosis. Mechanistically, NBP mainly improves microcirculation and protects mitochondria. Its broad pharmacologic effects also include inhibiting oxidative stress, nerve cell apoptosis, inflammatory responses, and anti-platelet and anti-thrombotic effects.

CONCLUSIONS

The varied pharmacologic mechanisms of NBP involve many complex molecular mechanisms; however, there many unknown pharmacologic effects await further study.