Effects of Acupuncture on Behavioral Stereotypies and Brain Dopamine System in Mice as a Model of Tourette Syndrome

Efficacy and Safety of Acupuncture for Tourette Syndrome in Children: A Meta-Analysis and Systematic Review

Despite the widespread use of acupuncture, its effectiveness and safety in treating Tourette syndrome (TS) remain controversial. Our research seeks to further evaluate the safety and effectiveness of acupuncture as a replacement therapy approach for children with TS. We conducted a comprehensive search for studies published from their inception to October 2023. The statistical analysis and subgroup analysis were conducted by software. Conduct a meta-analysis on the extracted data using the appropriate effect models. The meta-analysis was conducted on 26 studies consisting 1862 pediatric patients, which were selected from 976 identified articles. Acupuncture group demonstrated a significantly lower risk with a risk ratio (RR) of 0.29 (95% confidence interval [CI] = 0.19, 0.44, P < .0001), with only 5% of participants experiencing adverse reactions. Acupuncture treatment resulted in an 18% improvement in total effectiveness rates (RR = 1.18, 95% CI = [1.12, 1.25], P < .00001). The pooled data demonstrated that acupuncture therapy had a significant advantage in reducing the total score with the weighted mean difference (WMD) -4.92 (95% CI = [-6.38, -3.45], P < .00001) of the Yale Global Tic Severity Scale (YGTSS), the motor tic scores (WMD = -2.24, 95% CI = [-3.14, -1.35], P < .00001), the vocal tic scores (WMD: -2.34, 95% CI = [-3.31, -1.37], P < .00001), and the Traditional Chinese Medicine Syndrome Scores (TCMSS) (WMD: -2.47, 95% CI = [-2.87, -2.07], P < .0001). This meta-analysis reveals that acupuncture is more effective than most existing treatments in mitigating the symptoms of motor and vocal tics in children with TS, while also reducing the incidence of adverse reactions.

Vitamin D3 improves iminodipropionitrile-induced tic-like behavior in rats through regulation of GDNF/c-Ret signaling activity

Children with chronic tic disorders (CTD), including Tourette syndrome (TS), have significantly reduced serum 25-hydroxyvitamin D [25(OH)D]. While vitamin D3 supplementation (VDS) may reduce tic symptoms in these children, its mechanism is unclear. The study aim was to investigate the effects and mechanisms of vitamin D deficiency (VDD) and VDS on TS model behavior. Forty 5-week-old male Sprague-Dawley rats were randomly divided into (n = 10 each): control, TS model, TS model with VDD (TS + VDD), or TS model with VDS (TS + VDS; two intramuscular injections of 20,000 IU/200 g) groups. The VDD model was diet-induced (0 IU vitamin D/kg); the TS model was iminodipropionitrile (IDPN)-induced. All groups were tested for behavior, serum and striatal 25(OH)D and dopamine (DA), mRNA expressions of vitamin D receptor (VDR), glial cell line-derived neurotrophic factor (GDNF), protooncogene tyrosine-protein kinase receptor Ret (c-Ret), and DA D1 (DRD1) and D2 (DRD2) receptor genes in the striatum. TS + VDD had higher behavior activity scores throughout, and higher total behavior score at day 21 compared with TS model. In contrast, day 21 TS + VDS stereotyped behavior scores and total scores were lower than TS model. The serum 25(OH)D in TS + VDD was < 20 ng/mL, and lower than control. Striatal DA of TS was lower than control. Compared with TS model, striatal DA of TS + VDD was lower, while in TS + VDS it was higher than TS model. Furthermore, mRNA expression of VDR, GDNF, and c-Ret genes decreased in TS model, and GDNF expression decreased more in TS + VDD, while TS + VDS had higher GDNF and c-Ret expressions. VDD aggravates, and VDS ameliorates tic-like behavior in an IDPN-induced model. VDS may upregulate GDNF/c-Ret signaling activity through VDR, reversing the striatal DA decrease and alleviating tic-like behavior.

The mechanistic effects of acupuncture in rodent neurodegenerative disease models: a literature review

Neurodegenerative diseases refer to a battery of medical conditions that affect the survival and function of neurons in the brain, which are mainly presented with progressive loss of cognitive and/or motor function. Acupuncture showed benign effects in improving neurological deficits, especially on movement and cognitive function impairment. Here, we reviewed the therapeutic mechanisms of acupuncture at the neural circuit level in movement and cognition disorders, summarizing the influence of acupuncture in the dopaminergic system, glutamatergic system, γ-amino butyric acid-ergic (GABAergic) system, serotonergic system, cholinergic system, and glial cells at the circuit and synaptic levels. These findings can provide targets for clinical treatment and perspectives for further studies.

Electroacupuncture for Pain Relief After Endoscopic Sinus Surgery: A Randomized Controlled Trial

Postoperative pain is a common problem after endoscopic sinus surgery (ESS). Electroacupuncture (EA) is proven to be effective in relieving postoperative pain. However, EA has not been studied in patients undergoing ESS. This study was designed to evaluate the efficacy and safety of EA compared to a sham control in relieving pain after ESS. A total of 62 patients were randomly allocated to receive either EA (n = 31) or sham EA (n = 31) for 5 sessions, 30 minutes per session for 4 days (2 hours before and 2 hours after surgery, and 3 sessions daily for the following 3 days). There were no significant differences between the 2 groups with regard to demographic characteristics. Compared to the sham EA group, the EA group showed a significantly greater reduction in the pain intensity of single daily scoring with a numerical rating scale at the day following surgery (postoperative day 1, POD1) (-1.35; 95% confidence interval [CI], -1.74 to -0.97; P < .001) and POD2 (-1.16; 95% CI, -1.55 to -0.77; P < .001), whereas no significant between-group difference was detected at the day of surgery (POD0), POD3 or POD6. Intraoperative heart rate and mean blood pressure in the EA group showed a more stable trend. A significant improvement was found for an actigraphy-measured average time of night wakings, recovery time from anesthesia, and quality of recovery-15 in the EA group. No severe adverse events occurred during the trial. Our results demonstrate that EA can serve as an effective adjuvant therapeutic tool for pain relief after ESS. PERSPECTIVE: This randomized sham-controlled, patient-and-assessor blinded trial provided evidence for the first time that EA can relieve postoperative pain and other symptom management in patients after ESS. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry, ChiCTR1900024183, http://www.chictr.org.cn/showproj.aspx?proj=40573.

Electroacupuncture inhibits hippocampal neuronal apoptosis and improves cognitive dysfunction in mice with vascular dementia via the JNK signaling pathway

BACKGROUND

Electroacupuncture (EA) has been shown to reduce cognitive impairment in vascular dementia (VaD) patients. However, the mechanism of action remains unknown.

OBJECTIVE

The c-Jun N-terminal kinase (JNK) signaling pathway plays an important role in apoptosis. Herein, we focused on whether EA can inhibit apoptosis and alleviate cognitive impairment by regulating the JNK signaling pathway using a mouse model of VaD induced by modified bilateral common carotid artery occlusion (BCCAo).

METHODS

In experiment I, 60 mice were randomly divided into a Sham group, BCCAo group, BCCAo + EA group, BCCAo + Sham-EA group, BCCAo + SP group (receiving the selective JNK inhibitor SP600125) and BCCAo + SP + EA group. Morris water maze tests, TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining and flow cytometry were used to evaluate the effect of the EA intervention on VaD. In experiment II, 30 mice were randomly divided into a Sham group, BCCAo group, BCCAo + EA group, BCCAo + SP group and BCCAo + SP + EA group. Western blotting and real-time reverse transcription polymerase chain reaction were used to detect protein and mRNA expression of key factors in the JNK signaling pathway in the hippocampus.

RESULTS

EA, SP600125 and EA + SP600125 significantly inhibited hippocampal apoptosis and improved cognitive impairment in VaD model mice. There were no significant differences between the BCCAo group and the BCCAo + Sham-EA group. EA, EA + SP600125 and SP600125 inhibited the phosphorylation of JNK and caspase-3. EA and EA + SP600125 promoted protein and mRNA expression of B-cell lymphoma 2 (Bcl-2) in the hippocampus of VaD mice and inhibited protein and mRNA expression of activator protein (AP)-1, p53 and Bax.

CONCLUSION

EA can reverse cognitive deficits and inhibit hippocampal neuronal apoptosis in VaD model mice, at least partially through inhibition of the JNK signaling pathway and regulation of apoptosis signals.

Involvement of purinergic P2Y1R in antidepressant-like effects of electroacupuncture treatment on social isolation stress mice

Depression is a common neuropsychiatric disorder with high incidence and disability. Electroacupuncture (EA) is effective in the treatment of depression. However, the underlying mechanisms are not fully understood. Social isolation stress during post-weaning period can impair purinergic signaling in the brain of rodents and has emerged as a major risk factor for depression. The purpose of this study was to investigate the involvement of P2Y1 receptor (P2Y1R) in the antidepressant-like effects of EA. In this study, C57BL/6 mice were randomly assigned to group-housed (GH) or social isolated (SI) groups at post-natal day 21. After 6 weeks of social isolation, EA was performed on acupoints "Bai-hui" (GV20) and "Yin-tang" (GV29), or non-acupoints for 4 weeks. The SI mice received either intracerebroventricular injection of a selective P2Y1R agonist, MRS2365 (1 nmol); or a selective P2Y1R antagonist, MRS2179 (2 μmol), before and after EA. We found that SI mice exhibited depression-like behaviors accompanied with anxiety-like behaviors. The expressions of P2Y1R were well co-localized with GFAP-positive astrocytes and increased in the prefrontal cortex and hippocampus of SI mice. After treated with MRS2179, the depression-like behaviors of SI mice were attenuated, but not with MRS2365. Meanwhile, we found that EA could attenuate social isolation caused depression- and anxiety-like behaviors, and inhibited the up-regulation of P2Y1R in the prefrontal cortex and hippocampus of SI mice. Notably, the positive effects of EA on depression-like behaviors of SI mice could be reversed by MRS2365, while MRS2365 had no effect on the anxiolytic-like effects of EA. Therefore, we provide new evidence that EA could ameliorate depression- and anxiety-like behaviors in social isolation stress mice, and P2Y1R was involved in the antidepressant-like effects of EA.

The inflammatory injury in the striatal microglia-dopaminergic-neuron crosstalk involved in Tourette syndrome development

Background

Tourette syndrome (TS) is associated with immunological dysfunction. The DA system is closely related to TS development, or behavioral stereotypes. Previous evidence suggested that hyper-M1-polarized microglia may exist in the brains of TS individuals. However, the role of microglia in TS and their interaction with dopaminergic neurons is unclear. In this study, we applied iminodipropionitrile (IDPN) to establish a TS model and focused on the inflammatory injury in the striatal microglia-dopaminergic-neuron crosstalk.

Methods

Male Sprague-Dawley rats were intraperitoneally injected with IDPN for seven consecutive days. Stereotypic behavior was observed to verify the TS model. Striatal microglia activation was evaluated based on different markers and expressions of inflammatory factors. The striatal dopaminergic neurons were purified and co-cultured with different microglia groups, and dopamine-associated markers were assessed.

Results

First, there was pathological damage to striatal dopaminergic neurons in TS rats, as indicated by decreased expression of TH, DAT, and PITX3. Next, the TS group showed a trend of increased Iba-1 positive cells and elevated levels of inflammatory factors TNF-α and IL-6, as well as an enhanced M1-polarization marker (iNOS) and an attenuated M2-polarization marker (Arg-1). Finally, in the co-culture experiment, IL-4-treated microglia could upregulate the expression of TH, DAT, and PITX3 in striatal dopaminergic neurons vs LPS-treated microglia. Similarly, the TS group (microglia from TS rats) caused a decreased expression of TH, DAT, and PITX3 compared with the Sham group (microglia from control rats) in the dopaminergic neurons.

Conclusion

In the striatum of TS rats, microglia activation is M1 hyperpolarized, which transmits inflammatory injury to striatal dopaminergic neurons and disrupts normal dopamine signaling.

Mechanism of Qihuang needle therapy in the management of tic disorders: a clinical trial protocol

Background

Qihuang needle therapy is a newly developed acupuncture therapy to treat tic disorders in clinical practice. However, the mechanism to reduce tic severity remains unknown. Changes in intestinal flora and circulation metabolites are perhaps the potential pathogenesis of tic disorders. As a result, we present a protocol for a controlled clinical trial using multi-omics analysis to probe the mechanism of the Qihuang needle in managing tic disorders.

Methods

This is a matched-pairs design, controlled, clinical trial for patients with tic disorders. Participants will be allocated to either an experimental group or a healthy control group. The main acupoints are Baihui (GV20), Yintang (EX-HN3), and Jueyinshu (BL14). The experimental group will receive Qihuang needle therapy for a month, while the control group will receive no interventions.

Expected outcomes

The change in the severity of the tic disorder is set as the main outcome. Secondary outcomes include gastrointestinal severity index and recurrence rate, which will be calculated after a 12-week follow-up. Gut microbiota, measured by 16S rRNA gene sequencing; serum metabolomics, assessed via LC/MS; and serum zonulin, assessed by enzyme-linked immunosorbent assay (ELISA), will be used as biological specimen analysis outcomes. The present study will investigate the possible interactions between intestinal flora and serum metabolites and the improvement of clinical profiles, which may elucidate the mechanism of Qihuang needle therapy for tic disorders.

Trial registration

This trial is registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/). Registration number: ChiCTR2200057723, Date: 2022-04-14.

Effect of Electroacupuncture on Insomnia in Patients With Depression: A Randomized Clinical Trial

IMPORTANCE

Electroacupuncture (EA) is a widely recognized therapy for depression and sleep disorders in clinical practice, but its efficacy in the treatment of comorbid insomnia and depression remains uncertain.

OBJECTIVE

To assess the efficacy and safety of EA as an alternative therapy in improving sleep quality and mental state for patients with insomnia and depression.

DESIGN, SETTING, AND PARTICIPANTS

A 32-week patient- and assessor-blinded, randomized, sham-controlled clinical trial (8-week intervention plus 24-week observational follow-up) was conducted from September 1, 2016, to July 30, 2019, at 3 tertiary hospitals in Shanghai, China. Patients were randomized to receive EA treatment and standard care, sham acupuncture (SA) treatment and standard care, or standard care only as control. Patients were 18 to 70 years of age, had insomnia, and met the criteria for depression as classified in the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition). Data were analyzed from May 4 to September 13, 2020.

INTERVENTIONS

All patients in the 3 groups were provided with standard care guided by psychiatrists. Patients in the EA and SA groups received real or sham acupuncture treatment, 3 sessions per week for 8 weeks, for a total of 24 sessions.

MAIN OUTCOMES AND MEASURES

The primary outcome was change in Pittsburgh Sleep Quality Index (PSQI) from baseline to week 8. Secondary outcomes included PSQI at 12, 20, and 32 weeks of follow-up; sleep parameters recorded in actigraphy; Insomnia Severity Index; 17-item Hamilton Depression Rating Scale score; and Self-rating Anxiety Scale score.

RESULTS

Among the 270 patients (194 women [71.9%] and 76 men [28.1%]; mean [SD] age, 50.3 [14.2] years) included in the intention-to-treat analysis, 247 (91.5%) completed all outcome measurements at week 32, and 23 (8.5%) dropped out of the trial. The mean difference in PSQI from baseline to week 8 within the EA group was -6.2 (95% CI, -6.9 to -5.6). At week 8, the difference in PSQI score was -3.6 (95% CI, -4.4 to -2.8; P < .001) between the EA and SA groups and -5.1 (95% CI, -6.0 to -4.2; P < .001) between the EA and control groups. The efficacy of EA in treating insomnia was sustained during the 24-week postintervention follow-up. Significant improvement in the 17-item Hamilton Depression Rating Scale (-10.7 [95% CI, -11.8 to -9.7]), Insomnia Severity Index (-7.6 [95% CI, -8.5 to -6.7]), and Self-rating Anxiety Scale (-2.9 [95% CI, -4.1 to -1.7]) scores and the total sleep time recorded in the actigraphy (29.1 [95% CI, 21.5-36.7] minutes) was observed in the EA group during the 8-week intervention period (P < .001 for all). No between-group differences were found in the frequency of sleep awakenings. No serious adverse events were reported.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial of EA treatment for insomnia in patients with depression, quality of sleep improved significantly in the EA group compared with the SA or control group at week 8 and was sustained at week 32.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03122080.

Investigating Acupoint Selection and Combinations of Acupuncture for Tic Disorders: An Association Rule Mining and Network Analysis Study

Objective

Tic disorders (TDs) are common mental disorders in children and adolescents, and the clinical application of acupuncture for treating TDs is becoming increasingly widespread. However, the criteria for selecting acupoint prescriptions and combinations have not been summarized. Therefore, data mining was used herein to determine the treatment principles and the most effective acupoint selection and compatibility criteria for the treatment of TDs.

Methods

Clinical studies and observations of the efficacy of acupuncture treatment for TDs were obtained from the PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang, VIP, and Chinese Biomedical (CBM) databases. The data on the acupoint prescriptions applied in these studies were collected, and network and association analyses were used to reveal the relationships between acupoints and to identify acupoint combinations. Additionally, the principles of acupuncture for TDs were determined through cluster analysis. Subgroup analysis of acupuncture prescriptions based on specific categorical diagnoses was performed to further assess the selection of acupoints.

Results

Eighty-six trials were identified, and 257 groups of effective prescriptions involving 121 acupoints were extracted. Bai-hui (DU20), Feng-chi (GB20), Tai-chong (LR3), He-gu (LI4), and San-yin-jiao (SP6) were the most regularly used acupoints for treating TDs. The Governor Vessel, gallbladder, and large intestine meridians were more commonly used than other meridians. Moreover, most acupoint sites focused on the head and neck. Network analysis revealed potentially effective acupoint prescriptions for their commonly used acupoints, namely, Bai-hui (DU20), Si-shen-cong (EX-HN1), Feng-chi (GB20), Nei-guan (PC6), Shen-men (HT7), He-gu (LI4), Zu-san-li (ST36), San-yin-jiao (SP6) and Tai-chong (LR3). Association rule mining indicated that potential point combinations that should be prioritized in TD treatment are Bai-hui (DU20), Neiguan (PC6) and Sanyinjiao (SP6). Cluster analysis revealed the treatment principle of “coordinating yin and yang, tonifying qi and blood, dispelling pathogenic wind and eliminating phlegm”. The core acupoint prescription of TS treatment comprised He-gu (LI4), Feng-chi (GB20), Tai-chong (LR3), Bai-hui (DU20), Yin-tang (EX-HN3), Si-shen-cong (EX-HN1), San-yin-jiao (SP6), and Nei-guan (PC6). The core group included He-gu (LI4) and Feng-chi (GB20). Proximal points were usually used in TS as an additional method of point selection.

Conclusion

Using data mining analysis of published studies, this study provides valuable information regarding the selection of the most effective acupoints and point combinations for clinical acupuncture practice for treating TDs.

Fecal transplantation can alleviate tic severity in a Tourette syndrome mouse model by modulating intestinal flora and promoting serotonin secretion

Background

: Tourette syndrome (TS) is a neuropsychiatric disorder with onset in childhood that warrants effective therapies. Gut microbiota can affect central physiology and function via the microbiota–gut-brain axis. Therefore, the gut microbiota plays an important role in some mental illnesses. A small clinical trial showed that fecal microbiota transplantation (FMT) may alleviate TS symptoms in children. Herein, FMT effects and mechanisms were explored in a TS mouse model.

Methods

: TS mice model (TSMO) (n = 80) were established with 3,3′-iminodipropionitrile, and 80 mice were used as controls. Mice were grouped into eight groups and were subjected to FMT with feces from children or mice with or without TS, or were given probiotics. Fecal specimens were collected 3 weeks after FMT. 16S rRNA sequencing, behavioral observation, and serum serotonin (5-HT) assay were performed. Differences between groups were analyzed using Mann-Whitney U test and Kolmogorov-Smirnov (KS) tests.

Results

: A total of 18 discriminative microbial signatures (linear discriminant analysis score > 3) that varied significantly between TS and healthy mice (CONH) were identified. A significant increase in Turicibacteraceae and Ruminococcaceae in TSMO after FMT was observed (P < 0.05). Compared with non-transplanted TSMO, the symptoms of those transplanted with feces from CONH were alleviated (W = 336, P = 0.046). In the probiotic and FMT experiments, the serum 5-HT levels significantly increased in TSMO that received probiotics (KS = 1.423, P = 0.035) and in those transplanted with feces from CONH (W = 336.5, P = 0.046) compared with TSMO without transplantation.

Conclusions

: This study suggests that FMT may ameliorate TS by promoting 5-HT secretion, and it provides new insights into the underlying mechanisms of FMT as a treatment for TS.

Neuroinflammation in a Rat Model of Tourette Syndrome

Objective

Tourette syndrome (TS) is a group of childhood-onset chronic neuropsychiatric disorders characterized by tics, i.e., repetitive, sudden, and involuntary movements or vocalizations, which is often associated with various psychopathological and/or behavioral comorbidities, including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, depression, and sleep disorders and have a worse prognosis. The mechanism of TS is still not clear. The relationship between immune activation, neuroinflammation, and neuropsychiatric disorders has attracted much attention in the past two decades. To explore the underlying mechanism in TS, the relationship between neuroinflammation and behavioral alterations in TS rats was investigated in this study.

Methods

A total of 36 Sprague-Dawley male rats were divided into three groups randomly as follows: the TS, control (CON), and drug intervention groups. The TS rat group was treated with haloperidol (Hal) (the TS + Hal group). The TS rat model was established using 3,3-iminodipropionitrile (IDPN), which is a well-known animal model of TS. The behavioral syndromes, brain tissue cytokines, like interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α), and microglial activation of the three groups were assessed.

Results

The behavioral scores of rats in the TS group and the TS + Hal group were higher than those in the CON group (P < 0.05), but the scores of behavioral tests in the TS + Hal group were lower than those in the TS group (P < 0.05). The levels of IL-6 and TNF-α in the rat brain tissue were significantly higher in the TS group than in the CON group (P < 0.05), while no significant differences were found between the CON group and the TS + Hal group (P > 0.05). The microglia was significantly activated in the TS group and slightly activated in the TS + Hal group, which was considerably less than that in the TS group.

Conclusion

The IDPN-induced TS rats had significant neuroinflammation in the brain, and the interaction between dopamine (DA) dysregulation and immune dysfunction may play a vital role in the pathogenic mechanisms of TS.

The Impact of Electroacupuncture Early Intervention on the Brain Lipidome in a Mouse Model of Post-traumatic Stress Disorder

The neuroprotective effect of electroacupuncture (EA) treatment has been well studied; growing evidence suggests that changes in lipid composition may be involved in the pathogenesis of post-traumatic stress disorder (PTSD) and may be a target for treatment. However, the influence of early EA intervention on brain lipid composition in patients with PTSD has never been investigated. Using a modified single prolonged stress (mSPS) model in mice, we assessed the anti-PTSD-like effects of early intervention using EA and evaluated changes in lipid composition in the hippocampus and prefrontal cortex (PFC) using a mass spectrometry-based lipidomic approach. mSPS induced changes in lipid composition in the hippocampus, notably in the content of sphingolipids, glycerolipids, and fatty acyls. These lipid changes were more robust than those observed in the PFC. Early intervention with EA after mSPS ameliorated PTSD-like behaviors and partly normalized mSPS-induced lipid changes, notably in the hippocampus. Cumulatively, our data suggest that EA may reverse mSPS-induced PTSD-like behaviors due to region-specific regulation of the brain lipidome, providing new insights into the therapeutic mechanism of EA.

Electroacupuncture alleviates spatial memory deficits in METH withdrawal mice by enhancing astrocyte-mediated glutamate clearance in the dCA1

Methamphetamine (METH) elicits endogenous glutamate (Glu) in the brain, which could partially explain METH-induced memory deficits. Here, we investigated the therapeutic effects of electroacupuncture (EA) on spatial memory deficits in METH withdrawal mice and its potential synaptic mechanisms. We found that EA at acupoints 'Baihui' and 'Yintang' ameliorated the impaired spatial memory in METH withdrawal mice. In parallel, EA attenuated the Glu levels in vivo and suppressed the neuronal activities within dCA1 of METH withdrawal mice, as indicated by the decreasing c-Fos levels and the amplitude of mEPSP. In the dCA1, EA decreased A1-like astrocytes but increased astrocytic glutamatergic transporting molecules including glutamate transporter 1 and glutamine synthase. However, EA seemed to have no effects on presynaptic Glu transmission from the dCA3, as evidenced by the similiar levels of c-Fos in the dCA3 neurons, synaptic vesicular markers of dCA3 neural terminals and values of paired-pulse ratio in the dCA1 neurons between EA-treated and sham EA-treated METH withdrawal mice. These findings suggest that EA might normalize the dCA1 Glu levels at least in part through enhancing astrocyte-mediated Glu clearance. Taken together, astrocytes might be a novel target for developing therapeutic interventions against the impaired memory behaviours in METH users, and EA represents a promising non-invasive therapeutic strategy for the management of drug-caused memory deficits.

Effects of Chemogenetic Inhibition of D1 or D2 Receptor-Containing Neurons of the Substantia Nigra and Striatum in Mice With Tourette Syndrome

As tourette syndrome (TS) is a common neurobehavioral disorder, the primary symptoms of which include behavioral stereotypies. Dysfunction of the substantia nigra-striatum network could be the main pathogenesis of TS, which is closely associated with dopamine (DA) and its receptors. TS is often resistant to conventional treatments. Therefore, it is necessary to investigate the neurobiological mechanisms underlying its pathogenesis. In this study, we investigated whether chemogenetic activation or inhibition of dopaminergic D1 receptor (D1R)- or D2 receptor (D2R)-containing neurons in the substantia nigra pars compacta (SNpc) or dorsal striatum (dSTR) affected the stereotyped behavior and motor functions of TS mice. Intraperitoneal injection of 3,3'-iminodipropionitrile (IDPN) was used to induce TS in mice. Stereotyped behavior test and open-field, rotarod, and grip strength tests were performed to evaluate stereotyped behavior and motor functions, respectively. Immunofluorescence labeling was used to detect the co-labeling of virus fluorescence and D1R or D2R. We found that chemogenetic inhibition of D1R- or D2R-containing neurons in the SNpc and dSTR alleviated behavioral stereotypies and motor functions in TS mice. Chemogenetic activation of D1R-containing neurons in the dSTR aggravated behavioral stereotypies and motor functions in vehicle-treated mice, but neither was aggravated in TS mice. In conclusion, chemogenetic inhibition of D1R- or D2R-containing neurons in the SNpc and dSTR alleviated behavioral stereotypies of TS, providing a new treatment target for TS. Moreover, the activation of D1R-containing neurons in the dSTR may contribute to the pathogenesis of TS, which can be chosen as a more precise target for treatment.

Establishment and evaluation of a compound fear behavior model of Tourette's syndrome in rats

Background

Tourette syndrome (TS) is a common childhood disorder characterized by unwanted movements or vocal sounds called tics. It is often accompanied by other psychobehavioral disorders, including fearful behavior. The establishment and evaluation of rat models of TS and comorbid fear can provide an experimental basis for the treatment of TS and its comorbid fear disorder.

Methods

Sixteen rats were randomly divided into a model group (n=8) and control group (n=8). In the model group, rats were injected intraperitoneally with iminodipropionitrile (IDPN) for 1 week to establish the TS model, which was followed by acoustic and electrical stimulation for 3 weeks to establish the rat models of TS and comorbid fear. The control group received intraperitoneal injection of saline for 1 week, and no further intervention was given in the last 3 weeks. The behavioral changes of the rats were observed and analyzed by the open field test (OFT). Protein kinase A (PKA), cyclic adenosine monophosphate (cAMP), and dopamine (DA) were measured by enzyme-linked immunosorbent assay (ELISA), and tyrosine hydroxylase (TH) and microRNA-134 (miRNA-134) in the brain tissue were detected by using polymerase chain reaction (PCR).

Results

One rat in the model group died on the 24th day. Compared with the control group, the model group had significantly higher scores of locomotor activity, stereotyped behavior, and motor behavior, along with prolonged freezing time and significantly lower expression of miRNA-134. The differences in the expressions of PKA, cAMP, DA, and TH in brain tissue were not statistically significant.

Conclusions

The rat models of TS and comorbid fear have similar changes in behaviors and miRNA-134 level to those in clinical settings and therefore can be used as a reliable animal model to study the mechanism of action of TS and comorbid fear.

"Glu/GABA-Gln" metabolic loop abnormalities in iminodipropionitrile (IDPN)-induced dyskinetic syndrome

OBJECTIVE

Iminodipropionitrile (IDPN)-induced dyskinetic syndrome is characterized by abnormal repetitive involuntary movements with abnormalities in the neuro-transmission. This study explored the mechanism of glutamate (Glu)/γ-aminobutyric acid (GABA)-glutamine (Gln) metabolic circuit in rat dyskinetic syndrome and the possible regulation mechanism of "tiapride (Tia)."

METHODS

Male Wistar rats were assigned to the control group, dyskinetic syndrome group, and Tia group. Dyskinetic syndrome was induced by injecting with 3,3'-iminodipropionitrile for 7 days. Tia group was treated with tiapride, while the control and dyskinetic syndrome groups were gavaged with saline. Eventually the Glu, GABA, and Gln concentrations in striatum were detected using UPLC-3QMS, additionally another amino acid neurotransmitters (aspartate, glycine) were also detected. Expressions of glutamine synthetase (GS), glutamate transporter (EAAT₂), glutamate decarboxylase (GAD65/67), and γ-aminobutyric acid transporter protein (GAD-T) were observed using Western blot and real-time polymerase chain reaction.

RESULTS

The behavior test scores of dyskinetic syndrome group were increased compared with the control group. Tia group decreased the behavior test scores compared with dyskinetic syndrome group. For amino acid neuro-transmission, dyskinetic syndrome group increased Glu level (p < 0.01), decreased GABA level (p < 0.01), increased Glu/GABA ratio (p < 0.01), and decreased Asp level (p < 0.01) compared with control group. Tia group decreased Glu level (p < 0.01), increased GABA level (p < 0.01), decreased Glu/GABA ratio (p < 0.01), and increased Asp level (p < 0.05) compared with dyskinetic syndrome group. For Glu/GABA-Gln circuit, the protein and mRNA expression of GS and EAAT₂ in dyskinetic syndrome group were decreased (p < 0.05). Tia group increased protein and mRNA expression level of GS (p < 0.05) and EAAT₂ (p < 0.01).

CONCLUSION

The rat dyskinetic syndrome has Glu/GABA-Gln abnormalities. "Tiapride" upregulated the protein expression of GS and EAAT₂, reduce Glu levels, increase γ-GABA levels, and eventually improve amino acid neurotransmitter imbalance.

Electroacupuncture Attenuates Neuropathic Pain and Comorbid Negative Behavior: The Involvement of the Dopamine System in the Amygdala

Neuropathic pain (NeuP) is an important clinical problem accompanying negative mood symptoms. Neuroinflammation in the amygdala is critically involved in NeuP, and the dopamine (DA) system acts as an important endogenous anti-inflammatory pathway. Electroacupuncture (EA) can improve the clinical outcomes in NeuP, but the underlying mechanisms have not been fully elucidated. This study was designed to assess the effectiveness of EA on pain and pain-related depressive-like and anxiety-like behaviors and explore the role of the DA system in the effects of EA. Male Sprague-Dawley rats were subjected to the chronic constrictive injury (CCI) model to induce NeuP. EA treatment was carried out for 30 min once every other day for 3 weeks. The results showed that CCI caused mechanical hyperalgesia and depressive and anxiety-like behaviors in rats and neuroinflammation in the amygdala, such as an increased protein level of TNFα and IL-1β and activation of astrocytes. EA treatment significantly improved mechanical allodynia and the emotional dysfunction induced by CCI. The effects of EA were accompanied by markedly decreased expression of TNFα, IL-1β, and glial fibrillary acid protein (GFAP) in the amygdala. Moreover, EA treatment reversed CCI-induced down-regulation of DA concentration, tyrosine hydroxylase (TH) expression, and DRD1 and DRD2 receptors. These results suggest that EA-ameliorated NeuP may possibly be associated with the DA system to inhibit the neuroinflammation in the amygdala.

Electro-acupuncture alleviates adolescent cocaine exposure-enhanced anxiety-like behaviors in adult mice by attenuating the activities of PV interneurons in PrL

We recently found that adolescent cocaine exposure (ACE) resulted in an enhancement of the γ-aminobutyric acid (GABA) neurotransmitter system in the prelimbic cortex (PrL) of adult mice. Here, we aim to further investigate the role of GABAergic transmission, especially parvalbumin (PV) interneurons within PrL in the development of ACE-induced anxiety-like behavior, and to assess whether and how electro-acupuncture (EA) therapeutically manage the ACE-induced abnormal behaviors in adulthood. ACE mice exhibited the enhanced anxiety-like behaviors in their adulthood, accompanied by increased GABAergic transmission and PV interneurons in PrL. Chemogenetic blocking PV interneurons in PrL alleviated ACE-enhanced anxiety-like behaviors in mice. Importantly, 37-day EA treatments (mixture of 2 Hz/100 Hz, 1 mA, 30 minutes once a day) at the acupoints of Yintang (GV29) and Baihui (GV20) also alleviated ACE-induced anxiety-like behaviors, and rescued ACE-impaired GABAergic neurotransmitter system and PV interneurons in PrL. In parallel, EA treatments further suppressed the activities of pyramidal neurons in PrL, suggesting that EA treatments seem to perform it beneficial effects on the ACE-induced abnormal emotional behaviors by "calming down" the whole PrL. Collectively, these findings revealed that hyper-function of GABAergic transmission, especially mediating by PV interneurons in PrL may be key etiology underlying ACE-induced anxiety-like behaviors. At least by normalizing the function of GABAergic and PV interneurons, EA may represent a promising therapeutic strategy for managing adolescent substance use-related emotional disorders.