Immunological Dysfunction in Tourette Syndrome and Related Disorders

Shared molecular mechanisms and transdiagnostic potential of neurodevelopmental disorders and immune disorders

The co-occurrence and familial clustering of neurodevelopmental disorders and immune disorders suggest shared genetic risk factors. Based on genome-wide association summary statistics from five neurodevelopmental disorders and four immune disorders, we conducted genome-wide, local genetic correlation and polygenic overlap analysis. We further performed a cross-trait GWAS meta-analysis. Pleotropic loci shared between the two categories of diseases were mapped to candidate genes using multiple algorithms and approaches. Significant genetic correlations were observed between neurodevelopmental disorders and immune disorders, including both positive and negative correlations. Neurodevelopmental disorders exhibited higher polygenicity compared to immune disorders. Around 50%-90% of genetic variants of the immune disorders were shared with neurodevelopmental disorders. The cross-trait meta-analysis revealed 154 genome-wide significant loci, including 8 novel pleiotropic loci. Significant associations were observed for 30 loci with both types of diseases. Pathway analysis on the candidate genes at these loci revealed common pathways shared by the two types of diseases, including neural signaling, inflammatory response, and PI3K-Akt signaling pathway. In addition, 26 of the 30 lead SNPs were associated with blood cell traits. Neurodevelopmental disorders exhibit complex polygenic architecture, with a subset of individuals being at a heightened genetic risk for both neurodevelopmental and immune disorders. The identification of pleiotropic loci has important implications for exploring opportunities for drug repurposing, enabling more accurate patient stratification, and advancing genomics-informed precision in the medical field of neurodevelopmental disorders.

Effect of acupuncture on tic disorder: a randomized controlled clinical trial based on energy metabolomics and infrared thermography

BACKGROUND

Acupuncture is a method for treating tic disorder. However, there is a lack of sufficient clinical objective basis in regards of its treatment efficacy. Indeed, there are structural abnormalities present in energy metabolism and infrared thermography in children with tic disorder. Therefore, this study proposes a clinical trial scheme to explore the possible mechanism of acupuncture in treating tic disorder.

METHODS

This randomized controlled trial will recruit a total of 90 children, in which they will be divided into non-intervention group and intervention group. The non-intervention group consists of 30 healthy children while the intervention group consists of 60 children with tic disorder. The intervention group will be randomly allocated into either the treatment group or the control group, with 30 children randomly assigned in each group. Children either received acupuncture treatment and behavioral therapy (treatment group) or sham acupuncture treatment and behavioral therapy (control group), 3 treatment sessions per week for a period of 12 weeks, with a total of 36 treatment sessions. Outcome measures include YGTSS, urinary and fecal metabolomics, infrared thermography of body surface including governor vessel. For the intervention group, these outcome measures will be collected at the baseline and 90th day prior to intervention. Whereas for the non-intervention group, outcome measures (excluding YGTSS) will be collected at the baseline.

DISCUSSION

The main outcome will be to observe the changes of the severity of tic condition, the secondary outcome will be to observe the changes of structural characteristic of infrared thermography of body surface/acupoints along the governor vessel and to evaluate the changes of urinary and fecal metabolomics at the end of the treatment, so as to analyze the relationship between them and to provide further knowledge in understanding the possible mechanism of acupuncture in improving the clinical symptoms via regulating and restoring the body metabolomics network, which in future it can develop as a set of clinical guideline (diagnosis, treatment, assessment, prognosis) in treating tic disorder. ChiCTR2300075188(Chinese Clinical Trial Registry, http://www.chictr.org.cn , registered on 29 August 2023).

A review of common influencing factors and possible mechanisms associated with allergic diseases complicating tic disorders in children

Over the past few decades, the incidence of childhood allergic diseases has increased globally, and their impact on the affected child extends beyond the allergy itself. There is evidence of an association between childhood allergic diseases and the development of neurological disorders. Several studies have shown a correlation between allergic diseases and tic disorders (TD), and allergic diseases may be an important risk factor for TD. Possible factors influencing the development of these disorders include neurotransmitter imbalance, maternal anxiety or depression, gut microbial disorders, sleep disturbances, maternal allergic status, exposure to tobacco, and environmental factors. Moreover, gut microbial disturbances, altered immunological profiles, and DNA methylation in patients with allergic diseases may be potential mechanisms contributing to the development of TD. An in-depth investigation of the relationship between allergic diseases and TD in children will be important for preventing and treating TD.

Knockdown of the GABARAP ortholog Atg8a elicits deficits in learning and promotes obsessive behaviors in Drosophila melanogaster

In humans, trafficking of the GABA(A) receptor by GABARAP can lead to obsessive behaviors and learning deficits often in seen in neurological disorders such as Tourette's Syndrome. We find that in Drosophila melanogaster , Atg8a , the ortholog of the human GABARAP gene, is necessary in the nervous system for learning and suppression of excessive grooming. These results suggest that knocking down Atg8a in neurons of Drosophila produces a phenotype similar to that seen in human patients, potentially allowing for use of an Atg8a knockdown background as a suitable invertebrate model for related neurological conditions.

Association between body mass index and tic disorders in school-age children

OBJECTIVE

To explore the relationship between body mass index (BMI ) and the severity of tic disorders (TDs) in children 6-14 years old.

METHODS

A total of 86 children diagnosed with TDs in a hospital between Jan. 2023 and Sept. 2023 were collected by convenient sampling method, and the general data and TD-specific data were collected and analyzed.

RESULTS

Univariate analysis showed that patients with different Yale Global Tic Severity Scale (YGTSS) grades had statistically significant differences in age, BMI, residence, snacking pattern, weekly physical exercise frequency, weekly physical exercise time, and proportion of cesarean birth. Multiple linear regression analysis showed that the YGTSS score grades were related to BMI, snacking pattern, and cesarean birth of the patients. Correlation analysis revealed a positive correlation between BMI grades and the YGTSS score grades, with a higher BMI indicating more severe TDs. Predictive value evaluation showed that BMI, snacking pattern, and cesarean birth had predictive values for TD severity, and the highest value was found in the combined prediction.

CONCLUSION

BMI, snacking pattern, and cesarean birth are of predictive values for the severity of TDs. In addition, BMI is positively correlated with the severity of TDs, and a higher BMI suggests more severe TDs.

Biomarkers and Tourette syndrome: a systematic review and meta-analysis

Objective

This research aims to investigate whether peripheral biomarkers might differentiate individuals with Tourette syndrome (TS) from those without the condition.

Methods

A broad range of databases was searched through November 2022. This study employed a systematic literature review and subsequent meta-analysis of case-control studies that assessed the aberration of biomarkers of patients with TS and controls.

Results

A total of 81 studies were identified, out of which 60 met the eligibility criteria for inclusion in the meta-analysis. Following a meticulous screening procedure to determine the feasibility of incorporating case-control studies into the meta-analysis, 13 comparisons were statistically significant [CD3+ T cell, CD4+ T cell, CD4+ T cell to CD8+ T cell ratio, NK-cell, anti-streptolysin O antibodies, anti-DNase antibodies, glutamic acid (Glu), aspartic acid (Asp), ferritin (Fe), zinc (Zn), lead (Pb), vitamin D, and brain-derived neurotrophic factor (BDNF)]. Publication bias was found for anti-streptolysin O antibodies. Suggestive associations were evidenced for norsalsolinol (NSAL), neuron-specific enolase (NSE), and S100B.

Conclusion

In this study, we present empirical evidence substantiating the link between several peripheral biomarkers and the early diagnosis of TS. Larger and more standardized studies are necessary to replicate the observed results, elucidate the specificity of the biomarkers for TS, and evaluate their precision for use in clinical settings.

Tic disorder in allergic rhinitis children and adolescents: a case-control study

BACKGROUND

Allergic rhinitis is the most common allergic disease. It can accompany psychological disorders such as tic disorders due to the prolonged course of the symptoms of allergic rhinitis. This pioneer case-control study aims to investigate tic disorders in children and adolescents under 18 years of age diagnosed with allergic rhinitis.

METHOD

The case group in this study consisted of patients who had both allergic rhinitis and tic disorders. Patients with allergic rhinitis without tic disorders were also enrolled as the control group with matched gender and age. Demographic characteristics, tic classifications, and contributing factors for allergic rhinitis and tic disorders were studied among the cases. Tic disorders were evaluated using DSM-5 criteria for the classification of tic disorders.

RESULTS

47 patients in the case group and 47 patients in the control group were included in this study. 53.2% and 46.8% were males and females in the case group, respectively. The mean age of the patients was 10.46 ± 3.97 years old. Sound tics were more common among the patients compared to motor tics. Patients with concomitant AR and tic disorders had more days per week with AR symptoms (P-value ≤ 0.001; OR (every day vs. three days a week = 11.02(2.98, 40.76))). Most patients with sound tick were women (p: 0.026), and most patients with motion tic were in the Provisional tic disorder group (p: 0.001). The history of infantile eczema was seen more in patients without sound tic (p: 0.025), and otitis media was significantly less common among patients with sound tics (p: 0.026). Provisional tic disorder was the most common class among the patients. In the case group (coexistence between allergic rhinitis and tic) compared to the control group, patients had significantly more days with AR symptoms per week.

CONCLUSION

This preliminary study indicates that Provisional tic disorder was the most common classification of tic among patients with allergic rhinitis, especially in patients with motor tics. Asthma in motor tics, a history of food allergy in infancy, and a history of infantile eczema were also common among patients with vocal tics. Also, patients with allergic rhinitis and tic had more severe disease (more symptoms per week) than those with rhinitis alone. These findings emphasize the association of tic disorders with immunological pathways.

A bibliometric analysis of acupuncture for neurodevelopmental disorders: A Call for increased output and future research priorities

Objective

To perform a bibliometric analysis of published research on acupuncture for neurodevelopmental disorders and to provide new insights for future studies.

Methods

Web of Science Core Collection was used to search for articles on acupuncture for neurodevelopmental disorders in children, from inception to Dec 4, 2022. VOSviewer and CiteSpace software were used for bibliometric analyses. VOSviewer was used to analyze and visualize the knowledge maps of the articles' countries, authors, and institutions of origin, the journals and keywords. CiteSpace was used to visualize the dual-map overlay of the journals in which the articles were published and those publishing the articles they cited.

Results

A total of 119 papers were retrieved. The highest number of publications came from China, followed by the United States and South Korea. The most frequently cited article was from the United States, followed by China. The most publications were from KyungHee University, followed by Sichuan University. Author Cho, Seung-hun from KyungHee University published the most articles. The Journal of Alternative and Complementary Medicine and Medicine published the most articles. The top three most frequently used keywords were "acupuncture", "children", and "complementary".

Conclusion

Research intensity and recognition, as well as collaboration within the field of acupuncture for treating neurodevelopmental disorders in children has increased. Research is generally diverse and comprehensive, and the neuro-endocrine-immune mechanism should be a new direction for further development. More basic research is also needed, to elucidate the therapeutic mechanisms, to standardize and validate the use of acupuncture for neurodevelopmental disorders.

Transcranial Magnetic Stimulation for Developmental Neuropsychiatric Disorders with Inflammation

BACKGROUND

Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique that may potentially be helpful for neuropsychiatric symptoms of developmental disorders with inflammatory aspects. TMS utilizes a varying magnetic field to induce electrical changes in the brain. Repetitive use of TMS modulates plasticity at multiple levels, particularly at the synapse and network level.

SUMMARY

As inflammation can affect synaptic plasticity negatively, TMS may theoretically be a tool to address this inflammation-induced dysfunction. There are also data to suggest that TMS can directly downregulate inflammation. Neuropsychiatric consequences of multiple disorders with inflammatory aspects, particularly neurodevelopmental disorders like autism, Tourette syndrome, and obsessive-compulsive disorder (OCD), maybe treated effectively with TMS. Treatment of OCD, treatment-resistant major depression, and nicotine cessation (all in adults) are currently FDA-cleared indications, while migraine is cleared for ages 12 and above.

KEY MESSAGES

TMS will likely continue to grow in terms of indications as research continues to assess what brain networks are dysfunctional in various disorders and it becomes clearer how to modulate these networks. TMS may thus be best understood as a technology platform that can be utilized to modulate different brain networks affected in neuropsychiatric disorders. TMS is likely to become an increasingly important tool in targeting brain networks that could become dysfunctional in part due to inflammation in the developing brain and addressing consequent neuropsychiatric symptoms.

An Update on the Diagnosis and Management of Tic Disorders

Tic disorders (TDs) are a group of common neuropsychiatric disorders of childhood and adolescence. TDs may impact the physical, emotional, and social well-being of the affected person. In this review, we present an update on the clinical manifestations, pathophysiology, diagnosis, and treatment of TDs. We searched the PubMed database for articles on tics and Tourette syndrome. More than 400 articles were reviewed, of which 141 are included in this review. TDs are more prevalent in children than in adults and in males than in females. It may result from a complex interaction between various genetic, environmental, and immunological factors. Dysregulation in the cortico-striato-pallido-thalamo-cortical network is the most plausible pathophysiology resulting in tics. TD is a clinical diagnosis based on clinical features and findings on neurological examination, especially the identification of tic phenomenology. In addition to tics, TD patients may have sensory features, including premonitory urge; enhanced and persistent sensitivity to non-noxious external or internal stimuli; and behavioral manifestations, including attention deficit hyperactivity disorders, obsessive-compulsive disorders, and autism spectrum disorders. Clinical findings of hyperkinetic movements that usually mimic tics have been compared and contrasted with those of TD. Patients with TD may not require specific treatment if tics are not distressing. Psychoeducation and supportive therapy can help reduce tics when combined with medication. Dispelling myths and promoting acceptance are important to improve patient outcomes. Using European, Canadian, and American guidelines, the treatment of TD, including behavioral therapy, medical therapy, and emerging/experimental therapy, has been discussed.

Efficacy and Safety of Acupuncture Combined with Herbal Medicine for Children and Adolescents with Tourette Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

With the increasing prevalence of Tourette syndrome (TS), the search for alternative therapy for TS is a growing public concern. In recent years, a growing number of randomized controlled trials (RCTs) have revealed the value of acupuncture combined with herbal medicine for the treatment of TS; however, its holistic efficacy and safety remains unclear. This study aimed to evaluate the efficacy and safety of acupuncture combined with herbal medicine and to provide preliminary evidence for clinical practice.

METHODS

Eight databases were searched from their establishment to November 27, 2022, to collect RCTs of acupuncture combined with herbal medicine for TS treatment. Two researchers independently completed the study screening, data extraction, and risk of bias assessment by using NoteExpress, Excel, and Cochrane Risk of Bias Tool 2.0 (RoB 2.0). Stata 15.0 software was applied to conduct meta-analysis.

RESULTS

A total of 1,400 participants in 18 RCTs were included. Compared with the Western medicine, acupuncture combined with herbal medicine had better curative effect in the field of effective rate (risk ratio [RR] = 1.18, 95% CI: [1.12, 1.23], p < 0.05, I2 = 0%), Yale Global Tic Severity Scale (YGTSS) total score (mean difference [MD] = -3.91, 95% CI: [-5.49, -2.33], p < 0.05, I2 = 96.4%), TCM syndrome total score (MD = -2.42, 95% CI: [-3.71, -1.13], p < 0.05, I2 = 87.1%), and serum IgE negative rate (RR = 3.41, 95% CI: [1.69, 6.87], p < 0.05, I2 = 0%). Furthermore, acupuncture combined with herbal medicine reduced the adverse reaction rate (RR = 0.20, 95% CI: [0.14, 0.30], p < 0.05, I2 = 0%) and the recurrence rate (RR = 0.27, 95% CI: [0.13, 0.52], p < 0.05, I2 = 0%).

CONCLUSION

This study demonstrated the efficacy and safety of acupuncture combined with herbal medicine, which is probably a better alternative therapy for TS. However, the small number, low quality, and potential bias of the included studies caused the limitations of our results. More high-quality RCTs are required to provide supplementary evidence in the future.

Hintergrund

Mit der steigenden Prävalenz des Tourette-Syndroms (TS) ist die Suche nach alternativen Therapien für TS zunehmend zu einer Angelegenheit von öffentlichem Interesse geworden. In den vergangenen Jahren zeigte eine immer größer werdende Zahl randomisierter, kontrollierter Studien den Nutzen der Akupunktur in Kombination mit Heilkräutern; ihre ganzheitliche Wirksamkeit und Sicherheit ist jedoch weiterhin nicht klar. Mit dieser Studie sollten die Wirksamkeit und Sicherheit von Akupunktur in Kombination mit Heilkräutern beurteilt und erste Belege für die klinische Praxis gewonnen werden.

Methoden

Acht (8) Datenbanken wurden ab ihrer Einrichtung bis zum 27. November 2022 nach randomisierten kontrollierten Studien (RCTs) über Akupunktur in Kombination mit Heilkräutern zur Behandlung von TS durchsucht. Das Screening der Studien, die Datenextraktion und die Bewertung des Verzerrungsrisikos wurden von zwei unabhängigen Forschern mit Hilfe von NoteExpress, Excel und dem Cochrane Risk of Bias Tool 2.0 (RoB 2.0) durchgeführt. Die Metaanalyse erfolgte mit der Software Stata 15.0.

Ergebnisse

Insgesamt wurden 1400 Teilnehmer in 18 RCTs eingeschlossen. Im Vergleich zur westlichen Medizin (WM) hatte Akupunktur in Kombination mit Heilkräutern eine bessere kurative Wirkung in Bezug auf die Wirksamkeitsrate (RR = 1,18, 95%-KI [1,12, 1,23], p < 0,05, I2 = 0%), den Gesamtscore der Yale Global Tic Severity Scale (YGTSS) (MD = -3,91, 95%-KI [-5,49, -2,33], p < 0,05, I2 = 96,4%), den TCM-Syndrom-Gesamtscore (MD = -2,42, 95%-KI [-3,71, -1,13], p < 0,05, I2 = 87,1%) und die Serum-IgE-Negativrate (RR = 3,41, 95%-KI [1,69, 6,87], p <0,05, I2 = 0 %). Darüber hinaus verringerte Akupunktur in Kombination mit Heilkräutern die Nebenwirkungsrate (RR = 0,20, 95%-KI [0,14, 0,30], p < 0,05, I2 = 0%) sowie die Rezidivrate (RR = 0,27, 95%-KI [0,13, 0,52], p < 0,05, I2 = 0%).

Schlussfolgerung

Diese Studie belegt die Wirksamkeit und Sicherheit der Akupunktur in Kombination mit Heilkräutern, die wahrscheinlich eine bessere alternative Therapie für TS darstellt. Unsere Ergebnisse werden allerdings durch die geringe Zahl, die niedrige Qualität und die potenzielle Verzerrung der eingeschlossenen Studien eingeschränkt. Zukünftig sind weitere hochwertige RCTs erforderlich, die zusätzliche Belege liefern.

Can Red Blood Cell and Platelet Parameters Be Associated With Inflammation in Children With Tic Disorder?

OBJECTIVE

Tic disorder (TD) is one of the neurodevelopmental disorders and its etiology has not been fully elucidated. Complete blood count (CBC) values have been used as indicators of a systemic inflammatory response. In our study, we aimed to assess hemogram parameters in drug-naive, comorbidity-free children with TD compared with controls.

METHODS

This retrospective study included 62 drug-naive children with TD who had undergone CBC within one month prior to the study. A control group of 48 healthy children, matched for age and gender, without any organic or psychiatric disorders, was included. Statistical analysis was performed by using IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, New York, United States).  Results: Hematocrit (p = 0.044), mean corpuscular volume (p = 0.002), platelet count (p = 0.011), and plateletcrit (p = 0.031) values were significantly higher in the TD group, whereas mean corpuscular hemoglobin concentration (p = 0.00) was significantly lower in the TD group. Additionally, a significant negative correlation was observed between the duration of illness and platelet (p = 0.05, r=-0.282), plateletcrit (p = 0.038, r = -0.295), and neutrophil count (p = 0.006, r = -0.391), while a positive correlation was found between the duration of illness and eosinophil count (p = 0.018, r = 0.336).

CONCLUSION

The results revealed several significant differences in hemogram parameters between TD patients and the control group. These may suggest the role of inflammation and/or other underlying mechanisms in TD and may inspire new studies. Future studies with larger and more homogeneous samples, including comprehensive inflammatory markers, may contribute to a deeper understanding of the relationship between inflammation and TD.

Distinct patterns of GABAergic interneuron pathology in autism are associated with intellectual impairment and stereotypic behaviors

LAY ABSTRACT

Autism spectrum disorder is a neurodevelopmental condition characterized by deficits in sociability and communication and the presence of repetitive behaviors. How specific pathological alterations of the brain contribute to the clinical profile of autism spectrum disorder remains unknown. We previously found that a specific type of inhibitory interneuron is reduced in number in the autism spectrum disorder prefrontal cortex. Here, we assessed the relationship between interneuron reduction and autism spectrum disorder symptom severity. We collected clinical records from autism spectrum disorder (n = 20) and assessed the relationship between the severity of symptoms and interneuron number. We found that the reduced number of inhibitory interneurons that we previously reported is linked to specific symptoms of autism spectrum disorder, particularly stereotypic movements and intellectual impairments.

Hair Cortisol and Perceived Stress-Predictors for the Onset of Tics? A European Longitudinal Study on High-Risk Children

Some retrospective studies suggest that psychosocial stressors trigger the onset of tics. This study examined prospective hypothalamic-pituitary-adrenal (HPA) axis activity and perceived stress prior to tic onset. In the present study, 259 children at high risk for developing tics were assessed for hair cortisol concentration (HCC) and parent-on-child-reported perceived stress four-monthly over a three-year period. We used (i) generalised additive modelling (GAM) to investigate the time effects on HCC (hair samples n = 765) and perceived stress (questionnaires n = 1019) prior to tic onset and (ii) binary logistic regression to predict tic onset in a smaller subsample with at least three consecutive assessments (six to nine months before, two to five months before, and at tic onset). GAM results indicated a non-linear increasing course of HCC in children who developed tics, and a steady HCC course in those without tics, as well as a linear-increasing course of perceived stress in both groups. Logistic regression showed that with a higher HCC in hair samples collected in a range of two to five months before tic onset (which refers to cortisol exposure in a range of four to eight months), the relative likelihood of tic onset rose. Our study suggests increased stress prior to tic onset, as evidenced by higher HCC several months before tic onset.

Pediatric Acute-Onset Neuropsychiatric Syndrome: Current Perspectives

Pediatric acute-onset neuropsychiatric syndrome (PANS) features a heterogeneous constellation of acute obsessive-compulsive disorder (OCD), eating restriction, cognitive, behavioral and/or affective symptoms, often followed by a chronic course with cognitive deterioration. An immune-mediated etiology is advocated in which the CNS is hit by different pathogen-driven (auto)immune responses. This narrative review focused on recent clinical (ie, diagnostic criteria, pre-existing neurodevelopmental disorders, neuroimaging) and pathophysiological (ie, CSF, serum, genetic and autoimmune findings) aspects of PANS. We also summarized recent points to facilitate practitioners with the disease management. Relevant literature was obtained from PubMed database which included only English-written, full-text clinical studies, case reports, and reviews. Among a total of 1005 articles, 205 were pertinent to study inclusion. Expert opinions are converging on PANS as the effect of post-infectious events or stressors leading to "brain inflammation", as it is well-established for anti-neuronal psychosis. Interestingly, differentiating PANS from either autoimmune encephalitides and Sydenham's chorea or from alleged "pure" psychiatric disorders (OCD, tics, Tourette's syndrome), reveals several overlaps and more analogies than differences. Our review highlights the need for a comprehensive algorithm to help both patients during their acute distressing phase and physicians during their treatment decision. A full agreement on the hierarchy of each therapeutical intervention is missing owing to the limited number of randomized controlled trials. The current approach to PANS treatment emphasizes immunomodulation/anti-inflammatory treatments in association with both psychotropic and cognitive-behavioral therapies, while antibiotics are suggested when an active bacterial infection is established. A dimensional view, taking into account the multifactorial origin of psychiatric disorders, should suggest neuro-inflammation as a possible shared substrate of different psychiatric phenotypes. Hence, PANS and PANS-related disorders should be considered as a conceptual framework describing the etiological and phenotypical complexity of many psychiatric disorders.

Symptoms compatible with long COVID in an Italian pediatric cohort of Tourette patients with and without SARS‑CoV‑2 infection: a short-term follow-up assessment

BACKGROUND

Tourette Syndrome (TS) is a childhood-onset neurodevelopmental disorder with a worldwide prevalence of about 0.3-1% of the population. During the pandemic caused by SARS-CoV-2 infection, the impact on the mental health of children and adolescents was very important. The persistence of symptoms in the post-acute phase of the disease has been termed Long COVID. The neuropsychiatric symptoms seem to be the most common impairment in children and adolescents with long COVID.

OBJECTIVES

Considering the impact of pandemic on mental health, in this study we analyzed the long-term effects of SARS-CoV-2 infection in children and adolescents affected by TS.

METHODS

We conducted an online questionnaire covering socio-demographic and clinical data among 158 patients affected by TS or chronic tic disorders (CTD), of which 78 participants reported a positive SARS-CoV-2 infection. Data were collected to investigate tic severity and both the comorbidities, as well as lockdown-related changes to daily life activities and, in case of infection of SARS-CoV-2, possible symptoms of acute infection and long COVID. Markers of systemic inflammation including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), ferritin, iron, electrolytes, white blood cell counts, platelet cell counts levels, markers of liver, kidney and thyroid function were analyzed. First, all patients were screened with the Schedule for affective disorders and Schizophrenia for School age children-present and lifetime (Kiddie-SADS-PL) to rule out primary psychiatric disorders considered as criteria of exclusion. Then, all patients were clinically assessed at baseline (T0), and after three months (T1) through the administration of Yale Global Tic Severity Rating Scale (YGTSS), Multidimensional Anxiety Scale for Children (MASC), Child Depression Inventory (CDI) and Child Behavior Checklist (CBCL).

RESULTS

Among the cohort of TS patients that contracted SARS-CoV-2 infection, 84.6% (n = 66) experienced any acute symptoms, and long COVID symptoms occurred in 38.5% (n = 30). A worsening of clinical symptoms of tics and eventually associated comorbidities occurred in 34.6% (n = 27) of TS patients that contracted SARS-CoV-2 infection. TS patients with or without SARS-CoV-2 infection showed an increase in the severity of tics and also behavioral, depressive and anxious symptoms. Instead, this increase was more evident in patients who contracted the infection than in patients who did not contract it.

CONCLUSIONS

SARS-CoV-2 infection may have a role in the increase of tics and associated comorbidities in TS patients. Despite of these preliminary results, further investigations are necessary to improve knowledge about the acute and long-term impact of SARS-CoV-2 in TS patients.

Obsessive-Compulsive Disorder, PANDAS, and Tourette Syndrome: Immuno-inflammatory Disorders

In the last years, much focus has been given to the possible role of inflammatory and immunologic alterations in the pathophysiology of obsessive-compulsive disorder (OCD) and some related conditions, such as pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) and Tourette syndrome (TS). Although the matter is intriguing, the available data are still controversial and/or limited. Therefore, the aim of this chapter was at reviewing and commenting on the literature on possible dysfunctions of inflammatory and immune system processes in OCD, PANDAS, and TS.This narrative review was carried out through searching PubMed and Google Scholar for English language papers from January 1985 to December 31, 2021.The data gathered up to now would suggest that the mechanisms involved might be heterogeneous according to the age of the patients and the disorder examined. Indeed, PANDAS seem more related to infections triggering autoimmunity not necessarily following group A beta-hemolytic streptococcal (GABHS) infection, as supposed in the past. Autoimmunity seems also important in TS, if coupled with an individual vulnerability that can be genetic and/or environmental. The data in adult OCD, albeit scattered and sometimes obtained in small samples of patients, would indicate that immune system and inflammatory processes are involved in the pathophysiology of the disorder. However, it is still unclear to conclude whether they are primary or secondary phenomena.In conclusion, taken together, the current findings pave that way towards novel and promising domains to explore the pathophysiology of OCD and related disorders, as well towards the development of innovative therapeutic strategy beyond current pharmacological paradigms.

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.

Multimorbidity patterns and subgroups among autistic adults with intellectual disability: Results from the EFAAR study

LAY ABSTRACT

Multimorbidity relates to having multiple chronic health conditions. It is a risk factor for poor health and reduces life expectancy. Autistic people have multiple chronic health conditions and die prematurely, especially if they have an intellectual disability (autism spectrum disorder and intellectual disability). Certain pathophysiological processes observed in autism spectrum disorder are common to those related to the genesis and/or maintenance of multimorbidity. Furthermore, multimorbidity could be helpful in better identifying patient subgroups in autism spectrum disorder. It is therefore essential to better characterize multimorbidity and its consequences in the subgroup of autism spectrum disorder + intellectual disability individuals to offer them personalized care. We conducted a preliminary study of 63 autism spectrum disorder + intellectual disability adults to classify them according to their multimorbidity and search for a specific combination of chronic health conditions. We observed high and early multimorbidity in this sample and identified four classes of participants, distinguished by their multimorbidity status, independence and number of treatments. In addition, we observed a dominant combination of multimorbidity in our sample, combining immune dysfunction and gastrointestinal disorders, neurological and joint diseases. These findings support the hypothesis that an altered gut-brain relationship is involved in the risk of autism spectrum disorder, its outcome, and its association with chronic health conditions. Although larger studies are needed, our results suggest that subgroups of autism spectrum disorder + intellectual disability individuals can be identified based on their multimorbidity and potentially different ageing trajectories. A more comprehensive and personalized approach is needed to reduce the burden of multimorbidity and increase the quality of life and life expectancy in autism spectrum disorder/ intellectual disability.

Profiles of Proinflammatory Cytokines and T Cells in Patients With Tourette Syndrome: A Meta-Analysis

Background

Tic disorder is a neurodevelopmental disorder characterized by motor and phonic tic symptoms. Tourette syndrome (TS) is a subtype of tic disorder that shows more persistent tic symptoms. The etiological mechanism of TS concerning immune dysfunction remains unclear due to limited evidence, especially for pediatric TS patients.

Method

In the present study, a meta-analysis was performed to confirm the identified changes in proinflammatory cytokines and T cells of pediatric TS patients. A total of five databases, including PubMed, Web of Science, PsycINFO, Google Scholar and the China National Knowledge Infrastructure (CNKI), were used for the literature search. The standardized mean difference (SMD) and mean difference (MD) with a 95% confidence interval (CI) were used to present the effect size of each type of proinflammatory cytokine and T cell. Sensitivity analysis, subgroup analysis and meta-regression analysis were used to explore the heterogeneity of the meta-analysis. This meta-analysis was registered in the International Platform of Registered Systematic Review and Meta-analysis Protocols (number: INPLASY2021110079).

Results

In the 25 studies included in this meta-analysis, thirteen studies focused on the levels of T cells, and twelve studies focused on the levels of proinflammatory cytokines. Based on the random-effects model, the pooled MDs are -1.45 (95% CI: -3.44, 0.54) for CD3 cells, -4.44 (95% CI: -6.80, -2.08) for CD4 cells, and 1.94 (95% CI: -0.08, 3.97) for CD8 cells. The pooled SMDs are1.36 for IL-6 (95% CI: 0.00, 2.72) and 2.39 for tumor necrosis factor alpha (TNF-α) (95% CI: 0.93, 3.84).

Conclusion

We provided evidence of immune dysfunction in pediatric TS patients, with elevated levels of particular proinflammatory cytokines and disproportionate changes in T-cell subpopulations. Small to large effect sizes were identified for increased IL-6 levels as well as a reduced number of T helper cells, while a large effect size was identified for increased TNF-α levels. These results indicate a close association between peripheral immune activation and TS. However, the most direct and meaningful interaction between peripheral immune status and microglial activation in the central nervous system in TS patients requires further exploration.

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.

Correlation Between Tic Disorders and Serum 25-Hydroxyvitamin D Levels in Chinese Children

OBJECTIVE

To explore the correlation between serum 25-hydroxyvitamin D levels and tic disorders (TDs) in Chinese children.

METHODS

We selected 2960 children with TD and 2665 healthy controls, aged 5-14 years, from the Department of Neurology of the Shanghai Children's Hospital. Serum 25-hydroxyvitamin D levels and degrees of vitamin D deficiency were compared between patients with TD and healthy children.

RESULTS

The mean serum 25-hydroxyvitamin D level in the TD group was significantly lower than that in the control group (P < 0.001). The proportion of patients with 25-hydroxyvitamin D deficiency in the TD group was significantly higher than that in the control group. However, there was no correlation between 25-hydroxyvitamin D deficiency and the severity of TD. In addition, for age-wise comparison, mean levels of 25-hydroxyvitamin D and its deficiency in the TD group were the most significant in children over 9 years of age.

CONCLUSION

There is a correlation between 25-hydroxyvitamin D deficiency and TD in Chinese children, but not between 25-hydroxyvitamin D deficiency and the severity of TD. There was a correlation between age and deficiency of 25-hydroxyvitamin D; this deficiency was most pronounced among those over the age of 9 years.

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.

Towards an Ideology-Free, Truly Mechanistic Health Psychology

Efficient transfer of concepts and mechanistic insights from the cognitive to the health sciences and back requires a clear, objective description of the problem that this transfer ought to solve. Unfortunately, however, the actual descriptions are commonly penetrated with, and sometimes even motivated by, cultural norms and preferences, a problem that has colored scientific theorizing about behavioral control—the key concept for many psychological health interventions. We argue that ideologies have clouded our scientific thinking about mental health in two ways: by considering the societal utility of individuals and their behavior a key criterion for distinguishing between healthy and unhealthy people, and by dividing what actually seem to be continuous functions relating psychological and neurocognitive underpinnings to human behavior into binary, discrete categories that are then taken to define clinical phenomena. We suggest letting both traditions go and establish a health psychology that restrains from imposing societal values onto individuals, and then taking the fit between behavior and values to conceptualize unhealthiness. Instead, we promote a health psychology that reconstructs behavior that is considered to be problematic from well-understood mechanistic underpinnings of human behavior.

Recent progress on Tourette syndrome

Tic disorders and Tourette syndrome are the most common movement disorders in children and are characterized by movements or vocalizations. Clinically, Tourette syndrome is frequently associated with comorbid psychiatric symptoms. Although dysfunction of cortical–striatal–thalamic–cortical circuits with aberrant neurotransmitter function has been considered the proximate cause of tics, the mechanism underlying this association is unclear. Recently, many studies have been conducted to elucidate the epidemiology, clinical course, comorbid symptoms, and pathophysiology of tic disorders by using laboratory studies, neuroimaging, electrophysiological testing, environmental exposure, and genetic testing. In addition, many researchers have focused on treatment for tics, including behavioral therapy, pharmacological treatment, and surgical treatment. Here, we provide an overview of recent progress on Tourette syndrome.

Neuro-Immune Cross-Talk in the Striatum: From Basal Ganglia Physiology to Circuit Dysfunction

The basal ganglia network is represented by an interconnected group of subcortical nuclei traditionally thought to play a crucial role in motor learning and movement execution. During the last decades, knowledge about basal ganglia physiology significantly evolved and this network is now considered as a key regulator of important cognitive and emotional processes. Accordingly, the disruption of basal ganglia network dynamics represents a crucial pathogenic factor in many neurological and psychiatric disorders. The striatum is the input station of the circuit. Thanks to the synaptic properties of striatal medium spiny neurons (MSNs) and their ability to express synaptic plasticity, the striatum exerts a fundamental integrative and filtering role in the basal ganglia network, influencing the functional output of the whole circuit. Although it is currently established that the immune system is able to regulate neuronal transmission and plasticity in specific cortical areas, the role played by immune molecules and immune/glial cells in the modulation of intra-striatal connections and basal ganglia activity still needs to be clarified. In this manuscript, we review the available evidence of immune-based regulation of synaptic activity in the striatum, also discussing how an abnormal immune activation in this region could be involved in the pathogenesis of inflammatory and degenerative central nervous system (CNS) diseases.