Changes in inflammation are related to depression and amount of aerobic exercise in first episode schizophrenia

Exercise4Psychosis: A randomised control trial assessing the effect of moderate-to-vigorous exercise on inflammatory biomarkers and negative symptom profiles in men with first-episode psychosis

INTRODUCTION

First-Episode Psychosis (FEP) is a devastating mental health condition that commonly emerges during early adulthood, and is characterised by a disconnect in perceptions of reality. Current evidence suggests that inflammation and perturbed immune responses are involved in the pathology of FEP and may be associated specifically with negative symptoms. Exercise training is a potent anti-inflammatory stimulus that can reduce persistent inflammation, and can improve mood profiles in general populations. Therefore, exercise may represent a novel adjunct therapy for FEP. The aim of this study was to assess the effect of exercise on biomarkers of inflammation, negative symptoms of psychosis, and physiological health markers in FEP.

METHODS

Seventeen young males (26.67 ± 6.64 years) were recruited from Birmingham Early Intervention in Psychosis Services and randomised to a 6-week exercise programme consisting of two-to-three sessions per week that targeted 60-70 % heart-rate max (HRMax), or a treatment as usual (TAU) condition. Immune T-helper (Th-) cell phenotypes and cytokines, symptom severity, functional wellbeing, and cognition were assessed before and after 6-weeks of regular exercise.

RESULTS

Participants in the exercise group (n = 10) achieved 81.11 % attendance to the intervention, with an average exercise intensity of 67.54 % ± 7.75 % HRMax. This led to favourable changes in immune cell phenotypes, and a significant reduction in the Th1:Th2 ratio (-3.86 %) compared to the TAU group (p = 0.014). After the exercise intervention, there was also a significant reduction in plasma IL-6 concentration (-22.17 %) when compared to the TAU group (p = 0.006). IL-8, and IL-10 did not show statistically significant differences between the groups after exercise. Symptomatically, there was a significant reduction in negative symptoms after exercise (-13.54 %, Positive and Negative Syndrome Scale, (PANSS) Negative) when compared to the TAU group (p = 0.008). There were no significant change in positive or general symptoms, functional outcomes, or cognition (all p > 0.05).

DISCUSSION

Regular moderate-to-vigorous physical activity is feasible and attainable in clinical populations. Exercise represents a physiological tool that is capable of causing significant inflammatory biomarker change and concomitant symptom improvements in FEP cohorts, and may be useful for treatment of symptom profiles that are not targeted by currently prescribed antipsychotic medication.

The Impact of Regular Physical Exercise on Psychopathology, Cognition, and Quality of Life in Patients Diagnosed with Schizophrenia: A Scoping Review

The presence of less healthy lifestyle habits among individuals diagnosed with schizophrenia which can contribute to the escalation of physical disorders and exacerbation of psychological symptoms is well documented. The present scoping review aims to synthesize and evaluate the available evidence regarding the impact of regular physical exercise on psychopathology, cognition, and quality of life (QoL) in patients diagnosed with schizophrenia. A literature search was performed across Web of Science, SCOPUS, PubMed, and SPORTDiscus for randomized control trials published up to April 2022. Two independent reviewers applied the selection criteria and a third reviewer resolved discrepancies. A total of twelve studies were included, of which nine used endurance training and three used concurrent training (one of these additionally used resistance training). The results reveal benefits of various modalities of supervised regular exercise in the psychopathology of schizophrenia. Furthermore, regular endurance training seems to improve cognitive function in patients with schizophrenia and promote their QoL; however, results are inconclusive with respect to this last variable. The assessment of methodological quality in the reviewed articles indicates a high overall risk of bias, particularly in relation to deviations from intended interventions and the selection of reported results. Furthermore, an assessment of exercise reporting revealed that only 5 out of 19 items were fulfilled in more than 50% of the articles. Future research is needed to evaluate the effects of different training modalities and the optimal dose-response relationship in patients diagnosed with schizophrenia.

Study on the Mechanism for SIRT1 during the Process of Exercise Improving Depression

The mechanism behind the onset of depression has been the focus of current research in the neuroscience field. Silent information regulator 1 (SIRT1) is a key player in regulating energy metabolism, and it can regulate depression by mediating the inflammatory response (e.g., nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β)), gene expression in the nucleus accumben (NAc) and CA1 region of the hippocampus (e.g., nescient helix-loop-helix2 (NHLH2), monoamine oxidase (MAO-A), and 5-Hydroxyindole-3-acetic acid (5-HIAA)), and neuronal regeneration in the CA3 region of the hippocampus. Exercise is an important means to improve energy metabolism and depression, but it remains to be established how SIRT1 acts during exercise and improves depression. By induction and analysis, SIRT1 can be activated by exercise and then improve the function of the hypothalamic-pituitary-adrenal (HPA) axis by upregulating brain-derived neurotrophic factors (BDNF), inhibit the inflammatory response (suppression of the NF-κB and TNF-α/indoleamine 2,3-dioxygenase (IDO)/5-Hydroxytryptamine (5-HT) pathways), and promote neurogenesis (activation of the insulin-like growth factor1 (IGF-1) and growth-associated protein-43 (GAP-43) pathways, etc.), thereby improving depression. The present review gives a summary and an outlook based on this finding and makes an analysis, which will provide a new rationale and insight for the mechanism by which exercise improves depression.

Depression trajectories and cytokines in schizophrenia spectrum disorders - A longitudinal observational study

Depression occurs frequently in all phases of schizophrenia spectrum disorders. Altered activity in the immune system is seen in both depression and schizophrenia. We aimed to uncover depressive trajectories in a sample of 144 adult individuals with schizophrenia spectrum disorders followed for one year, in order to identify possible cytokine profile differences. Patients were assessed longitudinally with the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS), where a score above 6 predicts depression. The serum cytokine concentrations for tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, IL-12p70 and IL-17A were measured using immunoassays. Latent growth curve models, multilevel models and latent class growth analysis (LCGA) were applied. The LCGA model supported three latent classes (trajectories) with differing CDSS profiles during the one-year follow-up: a high CDSS group (40.8 % of participants), a moderate CDSS group (43.9 %) and a low CDSS group (15.3 %). Five single PANSS items predicted affiliation to depressive trajectory: hallucinations, difficulty in abstract thinking, anxiety, guilt feelings and tension. In the high CDSS group, despite diminishing psychotic symptoms, depressive symptoms persisted throughout one year. The pro-inflammatory cytokines IFN-γ, IL-1β and TNF-α were differentially distributed between the depressive trajectories, although levels remained remarkably stable throughout 12 months. Significant changes were found for the anti-inflammatory cytokine IL-10 at baseline with an accompanying difference in change over time. More research is required to optimize future treatment stratification and investigate the contribution of inflammation in depressed patients with schizophrenia spectrum disorders.

Linking Inflammation, Aberrant Glutamate-Dopamine Interaction, and Post-synaptic Changes: Translational Relevance for Schizophrenia and Antipsychotic Treatment: a Systematic Review

Evidence from clinical, preclinical, and post-mortem studies supports the inflammatory/immune hypothesis of schizophrenia pathogenesis. Less evident is the link between the inflammatory background and two well-recognized functional and structural findings of schizophrenia pathophysiology: the dopamine-glutamate aberrant interaction and the alteration of dendritic spines architecture, both believed to be the “quantal” elements of cortical-subcortical dysfunctional network. In this systematic review, we tried to capture the major findings linking inflammation, aberrant glutamate-dopamine interaction, and post-synaptic changes under a direct and inverse translational perspective, a paramount picture that at present is lacking. The inflammatory effects on dopaminergic function appear to be bidirectional: the inflammation influences dopamine release, and dopamine acts as a regulator of discrete inflammatory processes involved in schizophrenia such as dysregulated interleukin and kynurenine pathways. Furthermore, the link between inflammation and glutamate is strongly supported by clinical studies aimed at exploring overactive microglia in schizophrenia patients and maternal immune activation models, indicating impaired glutamate regulation and reduced N-methyl-D-aspartate receptor (NMDAR) function. In addition, an inflammatory/immune-induced alteration of post-synaptic density scaffold proteins, crucial for downstream NMDAR signaling and synaptic efficacy, has been demonstrated. According to these findings, a significant increase in plasma inflammatory markers has been found in schizophrenia patients compared to healthy controls, associated with reduced cortical integrity and functional connectivity, relevant to the cognitive deficit of schizophrenia. Finally, the link between altered inflammatory/immune responses raises relevant questions regarding potential new therapeutic strategies specifically for those forms of schizophrenia that are resistant to canonical antipsychotics or unresponsive to clozapine.

Old and New Biomarkers for Infection, Inflammation, and Autoimmunity in Treatment-Resistant Affective and Schizophrenic Spectrum Disorders

Affective (AF) and Schizophrenic (SZ) Spectrum disorders manifest with risk factors, involving inflammatory processes linked to infections and autoimmunity. This study searched for novel biomarkers in cerebrospinal fluid (CSF) and peripheral blood. A total of 29 AF and 39 SZ patients with treatment-resistant disease were included. In CSF, the chemokine IL-8 was significantly elevated in AF and SZ patients. IL-8 promotes chemotaxis by neutrophils and may originate from different tissues. S100B, a glia-derived brain damage marker, was higher in CSF from AF than SZ patients. Among the plasma-derived biomarkers, ferritin was elevated in AF and SZ. Soluble CD25, indicating Treg dysfunction, was higher in SZ than in AF patients. Interferon-γ, implying virus-specific immune activation, was positive in selective AF patients, only. Both groups showed elevated expression of immunosuppressive CD33 on monocytes, but higher amounts of CD123+ plasmacytoid dendritic cells were restricted to SZ. In conclusion, chemotactic IL-8 indicates neuronal stress and inflammation in the CSF of both groups. Novel plasma-derived biomarkers such as sCD25 and monocytic CD33 distinguish SZ from AF with an autoimmune phenotype.

Reduced Serum Levels of Soluble Interleukin-15 Receptor α in Schizophrenia and Its Relationship to the Excited Phenotype

Our previous studies documented that interleukin-15 receptor α (IL-15Rα) knockout (KO) mice exhibited hyperactivity, memory impairment, and desperate behavior, which are core features of schizophrenia and depression. Due to the overlapping symptomology and pathogenesis observed for schizophrenia and depression, the present study attempted to determine whether IL-15Rα was associated with the risk of schizophrenia or depression. One hundred fifty-six participants, including 63 schizophrenia patients, 29 depressive patients, and 64 age-matched healthy controls, were enrolled in the study. We investigated the circulating levels of soluble IL-15Rα and analyzed potential links between the IL-15Rα levels and clinical symptoms present in schizophrenia or depressive patients. We observed reduced serum IL-15Rα levels in schizophrenia patients, but not depressive patients compared with controls. Moreover, a significant negative association was observed between the circulating IL-15Rα levels and excited phenotypes in the schizophrenia patients. The IL-15Rα KO mice displayed pronounced pre-pulse inhibition impairment, which was a typical symptom of schizophrenia. Interestingly, the IL-15Rα KO mice exhibited a remarkable elevation in the startle amplitude in the startle reflex test compared to wild type mice. These results demonstrated that serum levels of soluble IL-15Rα were reduced in schizophrenia and highlighted the relationship of IL-15Rα and the excited phenotype in schizophrenia patients and mice.

Exploring low grade inflammation by soluble urokinase plasminogen activator receptor levels in schizophrenia: a sex-dependent association with depressive symptoms

BACKGROUND

There is evidence of increased low grade inflammation (LGI) in schizophrenia patients. However, the inter-individual variation is large and the association with demographic, somatic and psychiatric factors remains unclear. Our aim was to explore whether levels of the novel LGI marker soluble urokinase plasminogen activator receptor (suPAR) were associated with clinical factors in schizophrenia and if such associations were sex-dependent.

METHOD

In this observational study a total of 187 participants with schizophrenia (108 males, 79 females) underwent physical examination and assessment with clinical interviews (Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale for Schizophrenia (CDSS), Alcohol Use Disorder Identification Test (AUDIT), and Drug Use Disorder Identification Test (DUDIT)). Blood levels of suPAR, glucose, lipids, and high sensitivity C-reactive protein (hsCRP) were determined and body mass index (BMI) calculated. Multivariable linear regression analyses were used adjusting for confounders, and sex interaction tested in significant variables.

RESULTS

Adjusting for sex, age, current tobacco smoking and BMI, we found that levels of hsCRP and depressive symptoms (CDSS) were positively associated with levels of suPAR (p < 0.001). The association between suPAR and CDSS score was significant in females (p < 0.001) but not in males. Immune activation measured by hsCRP was not associated with depressive symptoms after adjusting for BMI.

CONCLUSION

Our findings indicate that increased suPAR levels are associated with depressive symptoms in females with schizophrenia, suggesting aberrant immune activation in this subgroup. Our results warrant further studies, including longitudinal follow-up of suPAR levels in schizophrenia and experimental studies of mechanisms.

The Effects and Mechanisms of Exercise on the Treatment of Depression

Background: It is necessary to seek alternative therapies for depression, because side effects of medications lead to poor adherence and some patients do not achieve a clinical treatment effect. Recently the role of exercise as a low-cost and easy-to-use treatment for depression has gained attention with a number of studies showing that exercise is effective at reducing depressive symptoms and improving body functions such as cardiorespiratory system and cognitive function. Because of the heterogeneity of exercise therapy programs, there is no standardized and unified program. Few studies have summarized the specific properties of exercise programs (type, intensity, duration, and frequency) and clinical prescriptions for exercise are not mentioned in most articles. Aims: This study aimed to investigate the feasibility and efficacy of exercise therapy for patients with depression, in order to appraise the evidence and outline accepted guidelines to direct individualized treatment plans for patients with depression based on their individual situations. Methods: A systematic review of English language literature including papers published from 2010 to present in PubMed was performed. Given the feasibility of prescribing exercise therapy for patients with depression, nearly 3 years of clinical studies on the treatments of depressive symptoms with exercise were first reviewed, comparing the exercise programs utilized. Conclusions: Exercise has therapeutic effects on depression in all age groups (mostly 18-65 years old), as a single therapy, an adjuvant therapy, or a combination therapy, and the benefits of exercise therapy are comparable to traditional treatments for depression. Moderate intensity exercise is enough to reduce depressive symptoms, but higher-dose exercise is better for overall functioning. Exercise therapy has become more widely used because of its benefits to the cardiovascular system, emotional state, and systemic functions. Recommendations: Aerobic exercise/mind-body exercise (3-5 sessions per week with moderate intensity lasting for 4-16 weeks) is recommended. Individualized protocols in the form of group exercise with supervision are effective at increasing adherence to treatment.

Alleviation of depression-like behavior in a cystic fibrosis mouse model by Hdac6 depletion

Cystic fibrosis (CF) patients experience heightened levels of anxiety and depression. Stress from dealing with chronic disease and rigorous treatment regimens certainly are primary contributors to these outcomes. We previously have demonstrated that microtubule alterations in CF are linked to a number of CF phenotypes including growth regulation and inflammatory responses to airway bacterial challenge. Deletion of histone deactelyase 6 (HDAC6), a cytosolic deacetylase that regulates tubulin acetylation, in CF mice restores growth and inflammatory phenotypes to wild type (WT) profiles. In this study, the hypothesis that Hdac6 depletion in CF mice would impact behaviors since Hda6 inhibition has been previously reported to have anti-depressive properties. Data demonstrate that CF mice exhibit reduced activity and reduced open arm time in an elevated plus maze test which can be consistent with anxiety-like behavior. CF mice also exhibit depression-like behaviors compared to WT mice in an age dependent manner. By eight weeks of age, CF mice exhibit significantly more immobile time in the tail-suspension test, however, Hdac6 depletion reverses the depressive phenotype. These data demonstrate that loss of CFTR function may predispose patients to experience depression and that this behavior is Hdac6 dependent.