The neurobiology of the switch process in bipolar disorder: a review

A bipolar disorder-associated missense variant alters adenylyl cyclase 2 activity and promotes mania-like behavior

The single nucleotide polymorphism rs13166360, causing a substitution of valine (Val) 147 to leucine (Leu) in the adenylyl cyclase 2 (ADCY2), has previously been associated with bipolar disorder (BD). Here we show that the disease-associated ADCY2 missense mutation diminishes the enzyme´s capacity to generate the second messenger 3',5'-cylic adenosine monophosphate (cAMP) by altering its subcellular localization. We established mice specifically carrying the Val to Leu substitution using CRISPR/Cas9-based gene editing. Mice homozygous for the Leu variant display symptoms of a mania-like state accompanied by cognitive impairments. Mutant animals show additional characteristic signs of rodent mania models, i.e., they are hypersensitive to amphetamine, the observed mania-like behaviors are responsive to lithium treatment and the Val to Leu substitution results in a shifted excitatory/inhibitory synaptic balance towards more excitation. Exposure to chronic social defeat stress switches homozygous Leu variant carriers from a mania- to a depressive-like state, a transition which is reminiscent of the alternations characterizing the symptomatology in BD patients. Single-cell RNA-seq (scRNA-seq) revealed widespread Adcy2 mRNA expression in numerous hippocampal cell types. Differentially expressed genes particularly identified from glutamatergic CA1 neurons point towards ADCY2 variant-dependent alterations in multiple biological processes including cAMP-related signaling pathways. These results validate ADCY2 as a BD risk gene, provide insights into underlying disease mechanisms, and potentially open novel avenues for therapeutic intervention strategies.

Lysophosphatidic Acid (LPA) and Its Receptors in Mood Regulation: A Systematic Review of the Molecular Mechanisms and Therapeutic Potential

Mood disorders affect over 300 million individuals worldwide, often characterized by their chronic and refractory nature, posing significant threats to patient life. There has been a notable increase in mood disorders among American adolescents and young adults, with a rising number of suicide attempts and fatalities, highlighting a growing association between mood disorders and suicidal outcomes. Dysregulation within the neuroimmune-endocrine system is now recognized as one of the fundamental biological mechanisms underlying mood and mood disorders. Lysophosphatidic acid (LPA), a novel mediator of mood behavior, induces anxiety-like and depression-like phenotypes through its receptors LPA1 and LPA5, regulating synaptic neurotransmission and plasticity. Consequently, LPA has garnered substantial interest in the study of mood regulation. This study aimed to elucidate the molecular mechanisms of lysophosphatidic acid and its receptors, along with LPA receptor ligands, in mood regulation and to explore their potential therapeutic efficacy in treating mood disorders. A comprehensive literature search was conducted using the PubMed and Web of Science databases, identifying 208 articles through keyword searches up to June 2024. After excluding duplicates, irrelevant publications, and those restricted by open access limitations, 21 scientific papers were included in this review. The findings indicate that LPA/LPA receptor modulation could be beneficial in treating mood disorders, suggesting that pharmacological agents or gintonin, an extract from ginseng, may serve as effective therapeutic strategies. This study opens new avenues for future research into how lysophosphatidic acid and its receptors, as well as lysophosphatidic acid receptor ligands, influence emotional behavior in animals and humans.

Molecular mechanisms of quetiapine bidirectional regulation of bipolar depression and mania based on network pharmacology and molecular docking: Evidence from computational biology

BACKGROUND

Quetiapine monotherapy is recommended as the first-line option for acute mania and acute bipolar depression. However, the mechanism of action of quetiapine is unclear. Network pharmacology and molecular docking were employed to determine the molecular mechanisms of quetiapine bidirectional regulation of bipolar depression and mania.

METHODS

Putative target genes for quetiapine were collected from the GeneCard, SwissTargetPrediction, and DrugBank databases. Targets for bipolar depression and bipolar mania were identified from the DisGeNET and GeneCards databases. A protein-protein interaction (PPI) network was generated using the String database and imported into Cytoscape. DAVID and the Bioinformatics platform were employed to perform the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the top 15 core targets. The drug-pathway-target-disease network was constructed using Cytoscape. Finally, molecular docking was performed to evaluate the interactions between quetiapine and potential targets.

RESULTS

Targets for quetiapine actions against bipolar depression (126 targets) and bipolar mania (81 targets) were identified. Based on PPI and KEGG pathway analyses, quetiapine may affect bipolar depression by targeting the MAPK and PI3K/AKT insulin signaling pathways via BDNF, INS, EGFR, IGF1, and NGF, and it may affect bipolar mania by targeting the neuroactive ligand-receptor interaction signaling pathway via HTR1A, HTR1B, HTR2A, DRD2, and GRIN2B. Molecular docking revealed good binding affinity between quetiapine and potential targets.

LIMITATIONS

Pharmacological experiments should be conducted to verify and further explore these results.

CONCLUSIONS

Our findings suggest that quetiapine affects bipolar depression and bipolar mania through distinct biological core targets, and thus through different mechanisms. Furthermore, our results provide a theoretical basis for the clinical use of quetiapine and possible directions for new drug development.

The Emergence of Mania After Initiating Escitalopram for Anxiety Disorder

The abrupt transition into mania, known as a bipolar switch, poses a significant challenge in the treatment of mental illnesses. We present a case of a 22-year-old Hispanic female with generalized anxiety disorder (GAD) and autism spectrum disorder (ASD) who developed mania within five days after initiating escitalopram 5 mg. The patient had no reported history of bipolar disorder prior to this episode, and an extensive medical workup ruled out organic causes. The patient was in the acute inpatient psychiatric unit for 25 days and returned to baseline after discontinuation of escitalopram and initiating divalproex and olanzapine. This case underscores the potential risk of a bipolar switch with antidepressant use and highlights the importance of vigilant monitoring and considering underlying bipolarity in such patients.

Environmental pollution and extreme weather conditions: insights into the effect on mental health

Environmental pollution exposures, including air, soil, water, light, and noise pollution, are critical issues that may implicate adverse mental health outcomes. Extreme weather conditions, such as hurricanes, floods, wildfires, and droughts, may also cause long-term severe concerns. However, the knowledge about possible psychiatric disorders associated with these exposures is currently not well disseminated. In this review, we aim to summarize the current knowledge on the impact of environmental pollution and extreme weather conditions on mental health, focusing on anxiety spectrum disorders, autism spectrum disorders, schizophrenia, and depression. In air pollution studies, increased concentrations of PM2.5, NO2, and SO2 were the most strongly associated with the exacerbation of anxiety, schizophrenia, and depression symptoms. We provide an overview of the suggested underlying pathomechanisms involved. We highlight that the pathogenesis of environmental pollution-related diseases is multifactorial, including increased oxidative stress, systematic inflammation, disruption of the blood-brain barrier, and epigenetic dysregulation. Light pollution and noise pollution were correlated with an increased risk of neurodegenerative disorders, particularly Alzheimer's disease. Moreover, the impact of soil and water pollution is discussed. Such compounds as crude oil, heavy metals, natural gas, agro-chemicals (pesticides, herbicides, and fertilizers), polycyclic or polynuclear aromatic hydrocarbons (PAH), solvents, lead (Pb), and asbestos were associated with detrimental impact on mental health. Extreme weather conditions were linked to depression and anxiety spectrum disorders, namely PTSD. Several policy recommendations and awareness campaigns should be implemented, advocating for the advancement of high-quality urbanization, the mitigation of environmental pollution, and, consequently, the enhancement of residents' mental health.

Prevalence and correlates of manic/hypomanic and depressive predominant polarity in bipolar disorder: systematic review and meta-analysis

BACKGROUND

Identification of the predominant polarity, i.e. hypomanic/manic (mPP) or depressive predominant polarity (dPP), might help clinicians to improve personalised management of bipolar disorder.

AIMS

We performed a systematic review and meta-analysis to estimate prevalence and correlates of mPP and dPP in bipolar disorder.

METHOD

The protocol was registered in the Open Science Framework Registries (https://doi.org/10.17605/OSF.IO/8S2HU). We searched main electronic databases up to December 2023 and performed random-effects meta-analyses of weighted prevalence of mPP and dPP. Odds ratios and weighted mean differences (WMDs) were used for relevant correlates.

RESULTS

We included 28 studies, providing information on rates and/or correlates of mPP and dPP. We estimated similar rates of mPP (weighted prevalence = 30.0%, 95% CI: 23.1 to 37.4%) and dPP (weighted prevalence = 28.5%, 95% CI: 23.7 to 33.7%) in bipolar disorder. Younger age (WMD = -3.19, 95% CI: -5.30 to -1.08 years), male gender (odds ratio = 1.39, 95% CI: 1.10 to 1.76), bipolar-I disorder (odds ratio = 4.82, 95% CI: 2.27 to 10.24), psychotic features (odds ratio = 1.56, 95% CI: 1.01 to 2.41), earlier onset (WMD = -1.57, 95% CI: -2.88 to -0.26 years) and manic onset (odds ratio = 13.54, 95% CI: 5.83 to 31.46) were associated with mPP (P < 0.05). Depressive onset (odds ratio = 12.09, 95% CI: 6.38 to 22.90), number of mood episodes (WMD = 0.99, 95% CI: 0.28 to 1.70 episodes), history of suicide attempts (odds ratio = 2.09, 95% CI: 1.49 to 2.93) and being in a relationship (odds ratio = 1.98, 95% CI: 1.22 to 3.22) were associated with dPP (P < 0.05). No differences were estimated for other variables.

CONCLUSIONS

Despite some limitations, our findings support the hypothesis that predominant polarity might be a useful specifier of bipolar disorder. Evidence quality was mixed, considering effects magnitude, consistency, precision and publication bias. Different predominant polarities may identify subgroups of patients with specific clinical characteristics.

Compulsive Biting and Chewing with Mixed Amphetamine Salts: A Case Report

Stimulants are the first-line pharmacological treatment for attention deficit hyperactivity disorder (ADHD). We present the unique case of a patient who developed a chewing compulsion when taking mixed amphetamine salts (MAS). A 32-year-old female patient with a past medical history of gastroesophageal reflux disease (GERD), gastroparesis, and migraines was seen for initial psychiatric assessment due to concerns for irritability. She was diagnosed with post-traumatic stress disorder (PTSD); generalized anxiety disorder; ADHD, inattentive type; and unspecified bipolar disorder. Lamotrigine was started and titrated to 25mg twice per day, with improved mood stability. MAS immediate-release (IR) was started at 2.5mg and titrated to 5mg daily for ADHD. She then experienced an uncontrollable urge to chew, finding relief when chewing on a child's teething necklace, which provided satisfaction and a reduction in anxiety. She denied jaw tightness or teeth grinding. The dose of MAS IR was reduced to 2.5mg daily with improvement in symptoms and later increased again to 5mg daily, which she was then able to tolerate. Stereotyped biting behaviors have been observed in rats with the use of amphetamines, and the onset of compulsive behavior has emerged in children with the use of dextroamphetamine. However, this is the first known case of compulsive chewing or biting movements reported in humans with MAS use. This case highlights the need to assess patients for adverse events, such as compulsive biting and chewing movements or other oral facial stereotypies, after commencement of stimulants, including MAS.

The emerging neuroimmune hypothesis of bipolar disorder: An updated overview of neuroimmune and microglial findings

Bipolar disorder (BD) is a severe and multifactorial disease, with onset usually in young adulthood, which follows a progressive course throughout life. Replicated epidemiological studies have suggested inflammatory mechanisms and neuroimmune risk factors as primary contributors to the onset and development of BD. While not all patients display overt markers of inflammation, significant evidence suggests that aberrant immune signaling contributes to all stages of the disease and seems to be mood phase dependent, likely explaining the heterogeneity of findings observed in this population. As the brain's immune cells, microglia orchestrate the brain's immune response and play a critical role in maintaining the brain's health across the lifespan. Microglia are also highly sensitive to environmental changes and respond to physiological and pathological events by adapting their functions, structure, and molecular expression. Recently, it has been highlighted that instead of a single population of cells, microglia comprise a heterogeneous community with specialized states adjusted according to the local molecular cues and intercellular interactions. Early evidence has highlighted the contribution of microglia to BD neuropathology, notably for severe outcomes, such as suicidality. However, the roles and diversity of microglial states in this disease are still largely undermined. This review brings an updated overview of current literature on the contribution of neuroimmune risk factors for the onset and progression of BD, the most prominent neuroimmune abnormalities (including biomarker, neuroimaging, ex vivo studies) and the most recent findings of microglial involvement in BD neuropathology. Combining these different shreds of evidence, we aim to propose a unifying hypothesis for BD pathophysiology centered on neuroimmune abnormalities and microglia. Also, we highlight the urgent need to apply novel multi-system biology approaches to characterize the diversity of microglial states and functions involved in this enigmatic disorder, which can open bright perspectives for novel biomarkers and therapeutic discoveries.

Predictive Value of qEEG in Manic Switch of Depressed Patients

Backgrounds: More than half of the patients with bipolar disorder (BD) had depressive episodes at the onset of BD. Despite some suggested clinical predictors, there are no certain criteria for predicting which unipolar depression patient switch to manic episodes during the treatment course. Electrophysiological markers can address this issue. Methods: Pretreatment quantitative electroencephalography (qEEG) records of patients diagnosed with major depressive disorder (MDD) or BD at the first visit were included in the study. Patients with MDD were also grouped with manic switch (MS) or MDD based on the diagnosis of later visits. The qEEG spectral power was analyzed across 3 groups, that is, MS, MDD, and BD. Results: Compared to patients whose diagnosis did not change, patients with MS had accelerated high-frequency activities predominantly in the left hemisphere (central-parietal-occipital regions). In contrast, they showed increased slow wave activity predominantly in the right hemisphere (parietal-occipital regions). Conclusion: It can be concluded that searching for electrophysiological markers, which have distinct advantages of repeatability, noninvasiveness, and cost-effectiveness, can facilitate the prediction of the MS.

G protein-biased LPAR1 agonism of prototypic antidepressants: Implication in the identification of novel therapeutic target for depression

Prototypic antidepressants, such as tricyclic/tetracyclic antidepressants (TCAs), have multiple pharmacological properties and have been considered to be more effective than newer antidepressants, such as selective serotonin reuptake inhibitors, in treating severe depression. However, the clinical contribution of non-monoaminergic effects of TCAs remains elusive. In this study, we discovered that amitriptyline, a typical TCA, directly binds to the lysophosphatidic acid receptor 1 (LPAR1), a G protein-coupled receptor, and activates downstream G protein signaling, while exerting a little effect on β-arrestin recruitment. This suggests that amitriptyline acts as a G protein-biased agonist of LPAR1. This biased agonism was specific to TCAs and was not observed with other antidepressants. LPAR1 was found to be involved in the behavioral effects of amitriptyline. Notably, long-term infusion of mouse hippocampus with the potent G protein-biased LPAR agonist OMPT, but not the non-biased agonist LPA, induced antidepressant-like behavior, indicating that G protein-biased agonism might be necessary for the antidepressant-like effects. Furthermore, RNA-seq analysis revealed that LPA and OMPT have opposite patterns of gene expression changes in the hippocampus. Pathway analysis indicated that long-term treatment with OMPT activated LPAR1 downstream signaling (Rho and MAPK), whereas LPA suppressed LPAR1 signaling. Our findings provide insights into the mechanisms underlying the non-monoaminergic antidepressant effects of TCAs and identify the G protein-biased agonism of LPAR1 as a promising target for the development of novel antidepressants.

The possible place for psychedelics in pharmacotherapy of mental disorders

Since its emergence in the 1960s, the serotonergic theory of depression bore fruit in the discovery of a plethora of antidepressant drugs affecting the lives of millions of patients. While crucial in the history of drug development, recent studies undermine the effectiveness of currently used antidepressant drugs in comparison to placebo, emphasizing the long time it takes to initiate the therapeutic response and numerous adverse effects. Thus, the scope of contemporary pharmacological research shifts from drugs affecting the serotonin system to rapid-acting antidepressant drugs. The prototypical representative of the aforementioned class is ketamine, an NMDA receptor antagonist capable of alleviating the symptoms of depression shortly after the drug administration. This discovery led to a paradigm shift, focusing on amino-acidic neurotransmitters and growth factors. Alas, the drug is not perfect, as its therapeutic effect diminishes circa 2 weeks after administration. Furthermore, it is not devoid of some severe side effects. However, there seems to be another, more efficient, and safer way to target the glutamatergic system. Hallucinogenic agonists of the 5-HT2A receptor, commonly known as psychedelics, are nowadays being reconsidered in clinical practice, shedding their infamous 1970s stigma. More and more clinical studies prove their clinical efficacy and rapid onset after a single administration while bearing fewer side effects. This review focuses on the current state-of-the-art literature and most recent clinical studies concerning the use of psychedelic drugs in the treatment of mental disorders. Specifically, the antidepressant potential of LSD, psilocybin, DMT, and 5-MeO-DMT will be discussed, together with a brief summary of other possible applications.

Biological rhythms are correlated with Na+, K+-ATPase and oxidative stress biomarkers: A translational study on bipolar disorder

BACKGROUND

Bipolar disorder (BD) is a chronic, severe, and multifactorial psychiatric disorder. Although biological rhythms alterations, sodium potassium pump (Na+, K+-ATPase) changes, and oxidative stress appear to play a critical role in the etiology and pathophysiology of BD, the inter-connection between them has not been described. Therefore this study evaluated the association between biological rhythms, Na+, K+-ATPase, and oxidative stress parameters in BD patients and the preclinical paradoxical sleep deprivation model (PSD).

METHODS

A translational study was conducted, including a case-control protocol with 36 BD and 46 healthy controls (HC). Subjects completed the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN). In addition, Erythrocyte Na+, K+-ATPase activity, and oxidative and nitrosative stress markers were assessed (4-hydroxynonenal [4-HNE], 8-isoprostane [8-ISO], thiobarbituric acid reactive substances [TBARS], carbonyl, 3-nitrotyrosine [3-nitro]). In the preclinical protocol, the same biomarkers were evaluated in the frontal cortex, hippocampus, and striatum from mice submitted to the PSD.

RESULTS

BD patients had a significantly higher total score of BRIAN versus HCs. Additionally, individuals with BD showed decreased Na+, K+-ATPase activity and increased oxidative stress parameters compared to HC without psychiatric disorders. This difference was driven by actively depressed BD subjects. The mice submitted to the PSD also demonstrated decreased Na+, K+-ATPase activity and increased oxidative stress parameters.

LIMITATIONS

BRIAN biological underpinning is less well characterized; We did not control for medication status; Sample size is limited; PSD it is not a true model of BD.

CONCLUSIONS

The present study found a significant correlation between Na+, K+-ATPase and oxidative stress with changes in biological rhythms, reinforcing the importance of these parameters to BD.

Deregulation of NF-κB associated long non-coding RNAs in bipolar disorder

Long non-coding RNAs (lncRNAs) are major genetic factors whose disruption lead to many diseases, including nervous system diseases. Bipolar disorder (BD) is a neuro-psychiatric disease with no definitive diagnosis and incomplete treatment. Regarding the role of NF-κB-associated lncRNAs in the neuro-psychiatric disorders, we examined the expression of three lncRNAs, DICER1-AS1, DILC, and CHAST, in BD patients. To assess lncRNA expression in peripheral blood mononuclear cells (PBMCs) of 50 BD patients and 50 healthy individuals, Real-time PCR was used. Additionally, some clinical characteristics of BD patients were investigated via an analysis of ROC curves and correlations. Based on our results, the expression level of CHAST increased significantly in BD patients in comparison with healthy people, in BD men compared with healthy men, as well as in BD women in comparison with control females (p < 0.05). A similar increase in expression was observed for DILC and DICER1-AS1 lncRNAs in female patients compared with healthy women. Whereas compared to healthy men, DILC was decreased in diseased men. Based on the results of the ROC curve, the area under the curve (AUC) for CHAST lncRNA was 0.83 with a P value of 0.0001. So, the expression level of CHAST lncRNA could play a role in the pathobiology of the BD and be considered a good putative biomarker for individuals with bipolar disorder.

A systematic review of manic/hypomanic and depressive switches in patients with bipolar disorder in naturalistic settings: The role of antidepressant and antipsychotic drugs

The present systematic review was aimed at critically summarizing the evidence about treatment-emergent manic/hypomanic and depressive switches during the course of bipolar disorder (BD). A systematic search of the MEDLINE, EMBASE, CINAHL, Web of Science, and PsycInfo electronic databases was conducted until March 24th, 2021, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Observational studies clearly reporting data regarding the prevalence of treatment-emergent mood switches in patients with BD were considered for inclusion. Thirty-two original studies met the inclusion criteria. In the majority of cases, manic switches were analyzed; only 3 papers investigated depressive switches in type I BD. Treatment-emergent mania/hypomania in BD subjects ranged from 17.3% to 48.8% and was more frequent with antidepressant monotherapy compared to combination treatment with mood stabilizers, especially lithium, or second-generation antipsychotics. A higher likelihood of mood switch has been reported with tricyclics and a lower rate with bupropion. Depressive switches were detected in 5-16% of type I BD subjects and were associated with first-generation antipsychotic use, the concomitant use of first- and second-generation antipsychotics, and benzodiazepines. The included studies presented considerable methodological heterogeneity, small sample sizes and comparability flaws. In conclusion, many studies, although heterogeneous and partly discordant, have been conducted on manic/hypomanic switches, whereas depressive switches during treatment with antipsychotics are poorly investigated. In BD subjects, both antidepressant and antipsychotic medications seems to play a role in the occurrence of mood switches, although the effects of different pharmacological compounds have yet to be fully investigated.

Atypical antipsychotic-induced mania: A systematic review and meta-analysis

BACKGROUND

The possibility of atypical antipsychotics (AA) to induce manic symptoms has been raised by several articles. The objective of this study was to describe whether exposure to AA may induce mania in mood disorders.

METHODS

We performed a systematic review following the preferred reporting items for systematic reviews and meta-analysis guidelines. The systematic search encompassed all relevant studies published until April 4th, 2022. A meta-analysis testing whether treatment emergent mania (TEM) is more frequent with the use of AA compared with placebo was performed.

RESULTS

A total of 52 studies were included in the systematic review. We found 24 case reports or case series describing 40 manic/hypomanic episodes allegedly induced by AA. Twenty-one placebo-controlled trials were included in a meta-analysis including 4823 individuals treated with AA and 3252 individuals receiving placebo. Our meta-analysis showed that the use of AA protects against the development of TEM (OR: 0.68 [95 % CI: 0.52-0.89], p = 0.005).

LIMITATIONS

AA-induced mania/hypomania was not the primary outcome in any of the observational or interventional studies. TEM was not homogeneously defined across studies. In most case reports it was not possible to establish causality between the use of AA and the development of manic symptoms.

CONCLUSIONS

TEM is more frequent with placebo than with AA, which suggests that AA exposure does not represent a relevant risk for TEM. Mania/hypomania induced by an AA seems to be rare events, since anecdotal evidence from case reports and case series were not observed in observational prospective and interventional studies.

"A sense of the bigger picture:" A qualitative analysis of follow-up interviews with people with bipolar disorder who self-reported psilocybin use

OBJECTIVES

People with bipolar disorder (BD) spend more time depressed than manic/hypomanic, and depression is associated with greater impairments in psychosocial functioning and quality of life than mania/hypomania. Emerging evidence suggests psilocybin, the psychoactive compound in "magic mushrooms," is a promising treatment for unipolar depression. Clinical trials of psilocybin therapy have excluded people with BD as a precaution against possible adverse effects (e.g., mania). Our study centered the experiences of adults living with BD who consumed psilocybin-containing mushrooms, and aimed to (1) understand its subjective impacts on BD symptoms, (2) deepen understanding of Phase I survey results, and (3) elucidate specific contextual factors associated with adverse reactions in naturalistic settings.

METHODS

Following an international survey (Phase I), follow-up interviews were conducted with 15 respondents (Phase II) to further understand psilocybin use among adults with BD. As part of a larger mixed-methods explanatory sequential design study, reflexive thematic analysis was used to elaborate findings.

RESULTS

Three major themes containing sub-themes were developed. (1) Mental Health Improvements: (1.1) decreased impact and severity of depression, (1.2) increased emotion processing, (1.3) development of new perspectives, and (1.4) greater relaxation and sleep. (2) Undesired Mental Health Impacts: (2.1) changes in sleep, (2.2) increased mania severity, (2.3) hospitalization, and (2.4) distressing sensory experiences. (3) Salient Contextual Factors for psilocybin use included: (3.1) poly-substance use and psilocybin dose, (3.2) solo versus social experiences, and (3.3) pre-psilocybin sleep deprivation.

CONCLUSION

Our findings demonstrate both benefits and risks of psilocybin use in this population. Carefully designed clinical trials focused on safety and preliminary efficacy are warranted.

What we know about the role of corticosteroids in psychiatric disorders; evidence from animal and clinical studies

Corticosteroids, often known as steroids, are anti-inflammatory medicine prescribed for various conditions. There is accumulating evidence of immune dysregulation in major psychiatric disorders. Significant changes in concentrations of inflammatory biomarkers (i.e., IL-6 and TNF-a) have been previously reported in individuals with schizophrenia, autistic individuals, and depressive patients. Thus, systemic corticosteroids can be used as an adjuvant treatment to reduce inflammation in major psychiatric disorders. However, despite their well-known potent anti-inflammatory and immunosuppressant properties, this treatment is often associated with increased severity of several psychiatric symptoms and relapse. This article reviews the available literature on psychiatric and cognitive changes during corticosteroid therapy. Specifically, we will provide data on the good and the bad of corticosteroid therapy in autism, schizophrenia, mood disorders, and PTSD. This review will summarize the vital role of corticosteroid therapy in social and cognitive behavior.

In silico analysis of metabolic effects of bipolar disorder on prefrontal cortex identified altered GABA, glutamate-glutamine cycle, energy metabolism and amino acid synthesis pathways

Bipolar disorder (BP) is a lifelong psychiatric condition, which often disrupts the daily life of the patients. It is characterized by unstable and periodic mood changes, which cause patients to display unusual shifts in mood, energy, activity levels, concentration and the ability to carry out day-to-day tasks. BP is a major psychiatric condition, and it is still undertreated. The causes and neural mechanisms of bipolar disorder are unclear, and diagnosis is still mostly based on psychiatric examination, furthermore the unstable character of the disorder makes diagnosis challenging. Identification of the molecular mechanisms underlying the disease may improve the diagnosis and treatment rates. Single nucleotide polymorphisms (SNP) and transcriptome profiles of patients were studied along with signalling pathways that are thought to be associated with bipolar disorder. Here, we present a computational approach that uses publicly available transcriptome data from bipolar disorder patients and healthy controls. Along with statistical analyses, data are integrated with a genome-scale metabolic model and protein-protein interaction network. Healthy individuals and bipolar disorder patients are compared based on their metabolic profiles. We hypothesize that energy metabolism alterations in bipolar disorder relate to perturbations in amino-acid metabolism and neuron-astrocyte exchange reactions. Due to changes in amino acid metabolism, neurotransmitters and their secretion from neurons and metabolic exchange pathways between neurons and astrocytes such as the glutamine-glutamate cycle are also altered. Changes in negatively charged (-1) KIV and KMV molecules are also observed, and it indicates that charge balance in the brain is highly altered in bipolar disorder. Due to this fact, we also hypothesize that positively charged lithium ions may stabilize the disturbed charge balance in neurons in addition to its effects on neurotransmission. To the best of our knowledge, our approach is unique as it is the first study using genome-scale metabolic models in neuropsychiatric research.

Association between thyroid autoimmunity and antidepressant treatment-emergent mania in pediatric mood disorders

Risk factors associated with antidepressant treatment-emergent mania(ATEM) are poorly characterized in child and adolescent populations. To identify better biomarkers, we aimed to explore whether thyroid autoimmunity is associated with ATEM in pediatric mood disorders. We enrolled two groups of pediatric mood disorders, those with ATEM+ (n = 29) and those with ATEM- controls (n = 31). All diagnoses were made according to structured interviews by the clinicians. Autoimmune thyroiditis (anti-thyroid peroxidase antibodies [TPO-abs] and thyroid function (thyroid-stimulating hormone [TSH] and free thyroxin [FT4]) were assessed. Logistic regression was used to explore the relationship between TPO-abs seroprevalence and ATEM+ while controlling for covariates. Group comparisons showed that the patient with ATEM+ had significantly higher seroprevalence and titer of TPO-abs compared to ATEM- controls. In logistic regression analysis adjusting for age, gender, Tanner stage, body mass index, antipsychotic treatments, smoking status and family history of thyroid disorder, the seroprevalence of TPO-abs (>60 U/mL) was significantly associated with ATEM+ (OR = 3.67, 95% confidence interval [CI] = 1.2-11.1, p = 0.022). Our findings demonstrated that seroprevalence and titer of TPO-abs in pediatric mood disorders are associated with ATEM+ status. TPO-abs could potentially serve as a biomarker when assessing the risk of ATEM in the child and adolescent population.

Effect of nighttime bedroom light exposure on mood episode relapses in bipolar disorder

OBJECTIVE

A previous cross-sectional study reported that nighttime light is associated with increased occurrence of manic symptoms in bipolar disorder; however, the longitudinal association between nighttime light and subsequent mood episode relapses remains unclear. We determined whether bedroom nighttime light was associated with mood episode relapses in patients with bipolar disorder.

METHODS

This prospective cohort study included 172 outpatients with bipolar disorder who participated in an Association between the Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study. A portable photometer was used to measure illuminance in the bedroom from bedtime to rising time during 7 consecutive nights for baseline assessment. Then, the participants were assessed at a 2-year follow-up for mood episode relapses.

RESULTS

Of the 172 participants, 157 (91%) completed the 2-year follow-up, and 39 (22%) experienced manic or hypomanic episodes (with or without mixed features), during that time. In the Cox proportional-hazards model, the hazard ratio (HR) for manic/hypomanic episode relapses was significantly higher when the average nighttime illuminance was ≥3 lux (n = 71) than when it was <3 lux (n = 101; HR, 2.54; 95% confidence interval (CI), 1.33-4.84). In the multivariable model adjusted for a propensity score in relation to nighttime light, the relationship remained significant (HR, 2.17; 95% CI, 1.04-4.52). The association between nighttime light and depressive episode relapses was not significantly different.

CONCLUSIONS

Keeping the bedroom dark at night may prevent hypomanic and manic episodes.

Characterization of Hemodynamic Alterations in Schizophrenia and Bipolar Disorder and Their Effect on Resting-State fMRI Functional Connectivity

Common and distinct neural bases of Schizophrenia (SZ) and bipolar disorder (BP) have been explored using resting-state fMRI (rs-fMRI) functional connectivity (FC). However, fMRI is an indirect measure of neural activity, which is a convolution of the hemodynamic response function (HRF) and latent neural activity. The HRF, which models neurovascular coupling, varies across the brain within and across individuals, and is altered in many psychiatric disorders. Given this background, this study had three aims: quantifying HRF aberrations in SZ and BP, measuring the impact of such HRF aberrations on FC group differences, and exploring the genetic basis of HRF aberrations. We estimated voxel-level HRFs by deconvolving rs-fMRI data obtained from SZ (N = 38), BP (N = 19), and matched healthy controls (N = 35). We identified HRF group differences (P < .05, FDR corrected) in many regions previously implicated in SZ/BP, with mediodorsal, habenular, and central lateral nuclei of the thalamus exhibiting HRF differences in all pairwise group comparisons. Thalamus seed-based FC analysis revealed that ignoring HRF variability results in false-positive and false-negative FC group differences, especially in insula, superior frontal, and lingual gyri. HRF was associated with DRD2 gene expression (P < .05, 1.62 < |Z| < 2.0), as well as with medication dose (P < .05, 1.75 < |Z| < 3.25). In this first study to report HRF aberrations in SZ and BP, we report the possible modulatory effect of dopaminergic signalling on HRF, and the impact that HRF variability can have on FC studies in clinical samples. To mitigate the impact of HRF variability on FC group differences, we suggest deconvolution during data preprocessing.

Key considerations for the use of ketamine and esketamine for the treatment of depression: focusing on administration, safety, and tolerability

INTRODUCTION

Racemic ketamine, a derivative of phencyclidine, has been used as a dissociative anesthetic since 1970. In 2000, the first randomized controlled trial showed a rapid relief of depressive symptoms. Since then, intravenous ketamine and intranasal S-ketamine have been validated for the treatment of depression and suicidal ideation following dose-response and double-blind placebo-controlled clinical trials. In clinical practice, after dose titration and with repeated treatments, patients may experience approximately 2-3 weeks of symptomatic relief from depression.

AREAS COVERED

Areas covered in this narrative review include mechanism of action, dosing, safety, and tolerability. Some attention is paid to the possibility of R-ketamine as a future antidepressant.

EXPERT OPINION

We recommend further investigation into treatment dosing and frequency strategies as well as approaches that prolong the therapeutic effects. The current fixed dosing of esketamine for obese individuals may be insufficient. Additional investigation into co-administration with somatic and neuromodulation treatments needs investigation. Finally, continuing to monitor research subjects and patients long-term for the emergence of adverse effects on cognition or other organ systems is critical.

Treatment-induced mood switching in affective disorders

Many patients under treatment for mood disorders, in particular patients with bipolar mood disorders, experience episodes of mood switching from one state to another. Various hypotheses have been proposed to explain the mechanism of mood switching, spontaneously or induced by drug treatment. Animal models have also been used to test the role of psychotropic drugs in the switching of mood states. We examine the possible relationship between the pharmacology of psychotropic drugs and their reported incidents of induced mood switching, with reference to the various hypotheses of mechanisms of mood switching.

Psycho-Behavioural Changes in Dogs Treated with Corticosteroids: A Clinical Behaviour Perspective

Simple Summary

Corticosteroids hormones are central to stress responses and, along with other hormones and neurotransmitters, contribute to the onset of physiological and behavioural changes aimed at helping the animal cope with anticipated demand. Both the human and animal literature suggest that exposure to systemic exogenous corticosteroid treatments can be associated with negative emotional states. In this paper, the potential behavioural effects of exogenous corticosteroid treatment on dogs and other species are discussed to show why consideration should be given to this matter when prescribing these drugs.

Abstract

Arousal and distress are often important factors in problematic behaviours, and endogenous corticosteroids are important mediators in the associated stress responses. Exogenous corticosteroid treatments have been reported to change behaviour in human patients and laboratory animals, with similar changes also noted in pet dogs. These behaviours not only potentially adversely impact the welfare of the dogs, but also the quality of life of their owners. Indeed, corticosteroids can bias sensitivity towards aversion in dogs. A decrease in behaviours associated with positive affective states, such as play and exploratory behaviours, together with an increase in aggression and barking have also been described in dogs. According to the available literature, human patients with pre-existing psychiatric disorders are more at risk of developing behavioural side effects due to corticosteroid treatments. It is reasonable to consider that the same may happen in dogs with pre-existing behavioural problems. In this paper, the possible behavioural side effects of exogenous corticosteroids are summarised to help inform and support veterinarians prescribing these drugs.

Index depressive episode and antidepressant exposure were associated with illness characteristics of pediatric bipolar disorder

OBJECTIVE

Pediatric bipolar disorder (PBD) is a serious, recurrent disorder leading to severe functional impairment. As a first mood episode, index episode could affect the long-term course of the illness. This study aimed to investigate the clinical characteristics of youth with PBD from our multicenter, nationwide, naturalistic follow-up samples and to identify (i) the effects of index mood episode and (ii) the effect of previous antidepressant treatments on the age at mania onset of PBD.

METHOD

The study sample consisted of 271 youth with BD-I followed by the child and adolescent psychiatry clinics of seven different university hospitals and three research state hospitals, representing six geographic regions across Turkey. All diagnoses were made according to structured interviews, and all data were retrospectively obtained from clinical records by the clinicians.

RESULTS

When patients with index depressive/mixed episodes (IDE, n=129) and patients with index (hypo)manic episodes (IME, n=142) were compared, the total number of mood episodes and rapid cycling feature were significantly higher in the IDE group than in the IME group. The Cox regression analysis adjusted for sociodemographic and illness characteristics revealed female adolescents in the IDE group treated with antidepressants were more likely to have an earlier onset of mania (hazard ratio=2.03, 95% confidence interval=1.31-3.12, p=0.001).

CONCLUSION

This is the first large-scale nationwide follow-up study in Turkey that indicated prior antidepressant treatments were associated with an earlier onset of mania in youth, particularly in adolescent females. Larger prospective studies are needed to identify neurodevelopmental processes underlying PBD and initiate prevention approaches.

Ketamine for treatment of mood disorders and suicidality: A narrative review of recent progress

BACKGROUND

Mood disorders are a leading cause of morbidity. Many patients experience treatment-resistant depression (TRD), and suicide rates are rising. Faster-acting and more effective antidepressant medications are needed. Four decades of research has transformed the use of ketamine from an anesthetic to an outpatient treatment for major depressive disorder (MDD). Ketamine is a N-methyl-d-aspartate (NMDA) receptor antagonist and has been shown to rapidly improve mood symptoms and suicidal ideation by targeting the glutamate system directly.

METHODS

We used the PubMed database to identify relevant articles published until September 1, 2020. We focused on meta-analyses, randomized controlled trials, and original observational studies. We included relevant studies for depression, MDD, TRD, bipolar disorder, anxiety, posttraumatic stress disorder (PTSD), suicide, ketamine, and esketamine.

RESULTS

Both racemic ketamine and esketamine have been shown to rapidly treat depression and suicidality. There is evidence that ketamine can be helpful for anxiety and PTSD; however, more research is needed. Intranasal esketamine has been FDA approved to treat depression.

CONCLUSIONS

This narrative review describes the evolution of ketamine to treat mood disorders and suicidality. We provide the evidence supporting recent developments using esketamine as well as unresolved issues in the field, such as dosing and safety.

Functional neuroanatomy of mania

Mania, the diagnostic hallmark of bipolar disorder, is an episodic disturbance of mood, sleep, behavior, and perception. Improved understanding of the neurobiology of mania is expected to allow for novel avenues to address current challenges in its diagnosis and treatment. Previous research focusing on the impairment of functional neuronal circuits and brain networks has resulted in heterogenous findings, possibly due to a focus on bipolar disorder and its several phases, rather than on the unique context of mania. Here we present a comprehensive overview of the evidence regarding the functional neuroanatomy of mania. Our interpretation of the best available evidence is consistent with a convergent model of lateralized circuit dysfunction in mania, with hypoactivity of the ventral prefrontal cortex in the right hemisphere, and hyperactivity of the amygdala, basal ganglia, and anterior cingulate cortex in the left hemisphere of the brain. Clarification of dysfunctional neuroanatomic substrates of mania may contribute not only to improve understanding of the neurobiology of bipolar disorder overall, but also highlights potential avenues for new circuit-based therapeutic approaches in the treatment of mania.

Bipolar spectrum disorders in neurologic disorders

Psychiatric symptoms frequently predate or complicate neurological disorders, such as neurodegenerative diseases. Symptoms of bipolar spectrum disorders (BSD), like mood, behavioral, and psychotic alterations, are known to occur - individually or as a syndromic cluster - in Parkinson's disease and in the behavioral variant of frontotemporal dementia (FTD). Nonetheless, due to shared pathophysiological mechanisms, or genetic predisposition, several other neurological disorders show significant, yet neglected, clinical and biological overlaps with BSD like neuroinflammation, ion channel dysfunctions, neurotransmission imbalance, or neurodegeneration. BSD pathophysiology is still largely unclear, but large-scale network dysfunctions are known to participate in the onset of mood disorders and psychotic symptoms. Thus, functional alterations can unleash BSD symptoms years before the evidence of an organic disease of the central nervous system. The aim of our narrative review was to illustrate the numerous intersections between BSD and neurological disorders from a clinical-biological point of view and the underlying predisposing factors, to guide future diagnostic and therapeutical research in the field.

The Elusive "Switch Process" in Bipolar Disorder and Photoperiodism: A Hypothesis Centering on NADPH Oxidase-Generated Reactive Oxygen Species Within the Bed Nucleus of the Stria Terminalis

One of the most striking and least understood aspects of mood disorders involves the "switch process" which drives the dramatic state changes characteristic of bipolar disorder. In this paper we explore the bipolar switch mechanism as deeply grounded in forms of seasonal switching (for example, from summer to winter phenotypes) displayed by many mammalian species. Thus we develop a new and unifying hypothesis that involves four specific claims, all converging to demonstrate a deeper affinity between the bipolar switch process and the light-sensitive (photoperiodic) nonhuman switch sequence than has been appreciated. First, we suggest that rapid eye movement (REM) sleep in both human and nonhuman plays a key role in probing for those seasonal changes in length of day that trigger the organism's characteristic involutional response (in certain animals, hibernation) to shorter days. Second, we claim that this general mammalian response requires the integrity of a neural circuit centering on the anterior bed nucleus of the stria terminalis. Third, we propose that a key molecular mediator of the switch process in both nonhumans and seasonal humans involves reactive oxygen species (ROS) of a particular provenance, namely those created by the enzyme NADPH oxidase (NOX). This position diverges from one currently prominent among students of bipolar disorder. In that tradition, the fact that patients afflicted with bipolar-spectrum disorders display indices of oxidative damage is marshaled to support the conclusion that ROS, escaping adventitiously from mitochondria, have a near-exclusive pathological role. Instead, we believe that ROS, originating instead in membrane-affiliated NOX enzymes upstream from mitochondria, take part in an eminently physiological signaling process at work to some degree in all mammals. Fourth and finally, we speculate that the diversion of ROS from that purposeful, genetically rooted seasonal switching task into the domain of human pathology represents a surprisingly recent phenomenon. It is one instigated mainly by anthropogenic modifications of the environment, especially "light pollution."

Selective serotonin reuptake inhibitors and manic switch: A pharmacovigilance and pharmacodynamical study

BACKGROUND

There is still no approved mechanism of manic switch in bipolar disorder, yet many selective serotonin reuptake inhibitors were accused for this important adverse event. Therefore, we aimed to investigate to estimate SSRI's risk for reporting mania and elevated mood using FEARS database and investigate receptor mechanisms involved.

METHODS

Mania and relevant side effects approved by FDA were screened in this dataset from the first quarter of 2004 to the third quarter of 2020. Disproportionality analysis were performed to estimate reporting odds ratio (ROR) and linear regressions were conducted to investigate relationship between ROR and Ki values. Receptor occupancy ratios were calculated from in vitro receptor binding profiles. The pharmacodynamical profile was extracted from the International Union of Basic and Clinical Pharmacology and the British Pharmacology Society dataset. Child and adolescent population was also investigated separately.

RESULTS

The analysis showed that the odds of a spontaneous report of mania in the FAERS database involving an SSRI were higher than the odds that such a report involved other types of drugs (ROR: 5.324 [CI: 3.773; 7.514]). The largest effect size in this estimation was found in fluvoxamine (ROR: 13.957 [CI: 10.391; 18.747]). Significant effects were found in regression analysis for Ki values of H1 and M1 receptors on ROR. Receptor occupation was not found to have an effect on ROR.

CONCLUSION

Lower degress of Ki values on M1 and H1 may be plausible pharmacological mechanism. Further pharmacological data and clinical assessments may be important to validate this safety signal.

Ketamine and other glutamate receptor modulators for depression in adults with bipolar disorder

BACKGROUND

Glutamergic system dysfunction has been implicated in the pathophysiology of bipolar depression. This is an update of the 2015 Cochrane Review for the use of glutamate receptor modulators for depression in bipolar disorder.

OBJECTIVES

1. To assess the effects of ketamine and other glutamate receptor modulators in alleviating the acute symptoms of depression in people with bipolar disorder. 2. To review the acceptability of ketamine and other glutamate receptor modulators in people with bipolar disorder who are experiencing depressive symptoms.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase and PsycINFO all years to July 2020.  We did not apply any restrictions to date, language or publication status.

SELECTION CRITERIA

RCTs comparing ketamine or other glutamate receptor modulators with other active psychotropic drugs or saline placebo in adults with bipolar depression.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, assessed trial quality and extracted data. Primary outcomes were response rate and adverse events. Secondary outcomes included remission rate, depression severity change scores, suicidality, cognition, quality of life, and dropout rate. The GRADE framework was used to assess the certainty of the evidence.

MAIN RESULTS

Ten studies (647 participants) were included in this review (an additional five studies compared to the 2015 review). There were no additional studies added to the comparisons identified in the 2015 Cochrane review on ketamine, memantine and cytidine versus placebo. However, three new comparisons were found: ketamine versus midazolam, N-acetylcysteine versus placebo, and riluzole versus placebo. The glutamate receptor modulators studied were ketamine (three trials), memantine (two), cytidine (one), N-acetylcysteine (three), and riluzole (one). Eight of these studies were placebo-controlled and two-armed. In seven trials the glutamate receptor modulators had been used as add-on drugs to mood stabilisers. Only one trial compared ketamine with an active comparator, midazolam. The treatment period ranged from a single intravenous administration (all ketamine studies), to repeated administration for riluzole, memantine, cytidine, and N-acetylcysteine (with a follow-up of eight weeks, 8 to 12 weeks, 12 weeks, and 16 to 20 weeks, respectively). Six of the studies included sites in the USA, one in Taiwan, one in Denmark, one in Australia, and in one study the location was unclear. All participants had a primary diagnosis of bipolar disorder and were experiencing an acute bipolar depressive episode, diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders fourth edition (IV) or fourth edition text revision (IV-TR). Among all glutamate receptor modulators included in this review, only ketamine appeared to be more efficacious than placebo 24 hours after infusion for response rate (odds ratio (OR) 11.61, 95% confidence interval (CI) 1.25 to 107.74; P = 0.03; participants = 33; studies = 2; I² = 0%, low-certainty evidence). Ketamine seemed to be more effective in reducing depression rating scale scores (MD -11.81, 95% CI -20.01 to -3.61; P = 0.005; participants = 32; studies = 2; I² = 0%, very low-certainty evidence). There was no evidence of ketamine's efficacy in producing remission over placebo at 24 hours (OR 5.16, 95% CI 0.51 to 52.30; P = 0.72; participants = 33; studies = 2; I² = 0%, very low-certainty evidence). Evidence on response, remission or depression rating scale scores between ketamine and midazolam was uncertain at 24 hours due to very low-certainty evidence (OR 3.20, 95% CI 0.23 to 45.19). In the one trial assessing ketamine and midazolam, there were no dropouts due to adverse effects or for any reason (very low-certainty evidence). Placebo may have been more effective than N-acetylcysteine in reducing depression rating scale scores at three months, although this was based on very low-certainty evidence (MD 1.28, 95% CI 0.24 to 2.31; participants = 58; studies = 2). Very uncertain evidence found no difference in response at three months (OR 0.82, 95% CI 0.32 to 2.14; participants = 69; studies = 2; very low-certainty evidence). No data were available for remission or acceptability. Extremely limited data were available for riluzole vs placebo, finding only very-low certainty evidence of no difference in dropout rates (OR 2.00, 95% CI 0.31 to 12.84; P = 0.46; participants = 19; studies = 1; I² = 0%).

AUTHORS' CONCLUSIONS

It is difficult to draw reliable conclusions from this review due to the certainty of the evidence being low to very low, and the relatively small amount of data usable for analysis in bipolar disorder, which is considerably less than the information available for unipolar depression. Nevertheless, we found uncertain evidence in favour of a single intravenous dose of ketamine (as add-on therapy to mood stabilisers) over placebo in terms of response rate up to 24 hours, however ketamine did not show any better efficacy for remission in bipolar depression. Even though ketamine has the potential to have a rapid and transient antidepressant effect, the efficacy of a single intravenous dose may be limited. We did not find conclusive evidence on adverse events with ketamine, and there was insufficient evidence to draw meaningful conclusions for the remaining glutamate receptor modulators. However, ketamine's psychotomimetic effects (such as delusions or delirium) may have compromised study blinding in some studies, and so we cannot rule out the potential bias introduced by inadequate blinding procedures. To draw more robust conclusions, further methodologically sound RCTs (with adequate blinding) are needed to explore different modes of administration of ketamine, and to study different methods of sustaining antidepressant response, such as repeated administrations.

Dynamics of data-driven microstates in bipolar disorder

Many of the existing models of mood in bipolar disorder can largely be divided into two camps, tracking mood as either a discrete or continuous variable. Both groups rely upon certain assumptions, with most considering only aggregate scores on clinical instruments. In this study, we propose a novel framework that combines elements from both discrete and continuous mood models, using a machine learning pipeline to detect subtle patterns across individuals. Latent factors are constructed from assessments at the item level, then clustered into groups referred to as microstates. Transitions between microstates are captured via a discrete-time Markov chain, allowing for characterization of mood's dynamic nature. Key findings include a factor mapping heavily onto irritability and aggression, as well as a hierarchical pattern of microstates within depression and mania. Validity of these results is confirmed by reproduction in an unseen data set from a separate subject cohort.

Genetic Association of Butyrylcholinesterase with Major Depressive Disorder

Major depressive disorder (MDD) is characterized as clinical depression, which primarily affects the mood and behaviour of an individual. In the present study butyrylcholinesterase (BChE), a co-regulatory cholinergic neurotransmitter enzyme implicated in several putative neuronal and non-neuronal physiological roles was investigated for its role in MDD. Eighty MDD patients and sixty-one healthy controls were recruited for the study. BChE activity was measured by Ellman's method using serum while DNA samples of the patients were genotyped for BCHE polymorphisms rs3495 (c.*189G > A) and rs1803274 (c.1699G > A) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and tetra-primer Amplification Refractory Mutation System- polymerase chain reaction (ARMS-PCR). The genotyping was further validated by Sanger Sequencing. Biochemical estimation of serum BChE levels revealed a statistically significant decrease of enzyme activity in MDD patients (69.96) as compared to healthy controls (90.97), which was independent of age and gender. BCHE single nucleotide polymorphism rs1803274 genotype GA was found to be associated with the disease under a dominant model (OR 2.32; 95% CI 1.09-4.96; p value = 0.025). Furthermore, risk allele-A frequency was higher in cases (p value = 0.013) than control. Carriers of rs1803274 GA genotype showed reduced mean BChE activity than wild-type allele GG homozygotes (p value = 0.040). Gender-based analysis revealed a protective role of rs3495 in females (χ² = 6.87, p value = 0.032, RM: OR 0.173, CI = 0.043-0.699 (p value = 0.017). In addition, rs1803274 risk allele-A was observed to be significantly higher in males (χ² = 4.258, p value = 0.039). In conclusion, the present study is indicative of a role of BChE in the pathophysiology of MDD where genetic polymorphisms were observed to effect BChE activity. Further replication studies in different ethnicities are recommended to validate the current observations.

Dissociation Pattern in Default-Mode Network Homogeneity in Drug-Naive Bipolar Disorder

Default mode network (DMN) plays a key role in the pathophysiology of in bipolar disorder (BD). However, the homogeneity of this network in BD is still poorly understood. This study aimed to investigate abnormalities in the NH of the DMN at rest and the correlation between the NH of DMN and clinical variables in patients with BD. Forty drug-naive patients with BD and thirty-seven healthy control subjects participated in the study. Network homogeneity (NH) and independent component analysis (ICA) methods were used for data analysis. Support vector machines (SVM) method was used to analyze NH in different brain regions. Compared with healthy controls, significantly increased NH in the left superior medial prefrontal cortex (MPFC) and decreased NH in the right posterior cingulate cortex (PCC) and bilateral precuneus were found in patients with BD. NH in the right PCC was positively correlated with the verbal fluency test and verbal function total scores. NH in the left superior MPFC was negatively correlated with triglyceride (TG). NH in the right PCC was positively correlated with TG but negatively correlated with high-density lipoprotein cholesterol (HDL-C). NH in the bilateral precuneus was positively correlated with cholesterol and low-density lipoprotein cholesterol (LDL-C). In addition, NH in the left superior MPFC showed high sensitivity (80.00%), specificity (71.43%), and accuracy (75.61%) in the SVM results. These findings contribute new evidence of the participation of the altered NH of the DMN in the pathophysiology of BD.

Enlightened: addressing circadian and seasonal changes in photoperiod in animal models of bipolar disorder

Bipolar disorders (BDs) exhibit high heritability and symptoms typically first occur during late adolescence or early adulthood. Affected individuals may experience alternating bouts of mania/hypomania and depression, with euthymic periods of varying lengths interspersed between these extremes of mood. Clinical research studies have consistently demonstrated that BD patients have disturbances in circadian and seasonal rhythms, even when they are free of symptoms. In addition, some BD patients display seasonal patterns in the occurrence of manic/hypomanic and depressive episodes as well as the time of year when symptoms initially occur. Finally, the age of onset of BD symptoms is strongly influenced by the distance one lives from the equator. With few exceptions, animal models useful in the study of BD have not capitalized on these clinical findings regarding seasonal patterns in BD to explore molecular mechanisms associated with the expression of mania- and depression-like behaviors in laboratory animals. In particular, animal models would be especially useful in studying how rates of change in photoperiod that occur during early spring and fall interact with risk genes to increase the occurrence of mania- and depression-like phenotypes, respectively. Another unanswered question relates to the ways in which seasonally relevant changes in photoperiod affect responses to acute and chronic stressors in animal models. Going forward, we suggest ways in which translational research with animal models of BD could be strengthened through carefully controlled manipulations of photoperiod to enhance our understanding of mechanisms underlying seasonal patterns of BD symptoms in humans. In addition, we emphasize the value of incorporating diurnal rodent species as more appropriate animal models to study the effects of seasonal changes in light on symptoms of depression and mania that are characteristic of BD in humans.

Bipolar disorder: An evolutionary psychoneuroimmunological approach

Bipolar disorder is a mental health disorder characterized by extreme shifts in mood, high suicide rate, sleep problems, and dysfunction of psychological traits like self-esteem (feeling inferior when depressed and superior when manic). Bipolar disorder is rare among populations that have not adopted contemporary Western lifestyles, which supports the hypothesis that bipolar disorder results from a mismatch between Homo sapiens's evolutionary and current environments. Recent studies have connected bipolar disorder with low-grade inflammation, the malfunctioning of the internal clock, and the resulting sleep disturbances. Stress is often a triggering factor for mania and sleep problems, but stress also causes low-grade inflammation. Since inflammation desynchronizes the internal clock, chronic stress and inflammation are the primary biological mechanisms behind bipolar disorder. Chronic stress and inflammation are driven by contemporary Western lifestyles, including stressful social environments, unhealthy dietary patterns, limited physical activity, and obesity. The treatment of bipolar disorder should focus on reducing stress, stress sensitivity, and inflammation by lifestyle changes rather than just temporarily alleviating symptoms with psychopharmacological interventions.

Sleep deprivation as treatment for depression: Systematic review and meta-analysis

OBJECTIVE

To systematically review evidence on the efficacy and safety of sleep deprivation (SD) as a treatment option for patients with unipolar or bipolar depression.

METHODS

A systematic review according to PRISMA guidelines was conducted. The certainty of evidence was assessed using the GRADE approach. Controlled trials were included in efficacy analysis, case series for evaluating complications and qualitative studies for patients' experiences.

RESULTS

Eight controlled studies (368 patients), one qualitative study and seven case series (825 patients) were included. One week after treatment start, SD combined with standard treatment did not reduce depressive symptoms compared with standard treatment (standardized mean difference, SMD = -0.29, [95% confidence interval, CI: -0.84 to 0.25], p = 0.29). When excluding a study in elderly patients in a post hoc analysis, the difference was statistically significant (SMD = -0.54 ([95% CI: -0.86 to -0.22], p < 0.001)) but it diminished two weeks after treatment start. No superiority of SD was found compared with antidepressants, but SD may be superior to exercise in certain settings. It is uncertain whether SD affects quality of sleep, quality of life, everyday functioning or length of stay. Apart from switch to mania (ranging between 2.7% and 10.7%), no other serious complications were reported.

CONCLUSION

Sleep deprivation has been studied in a wide range of settings resulting in divergent results for the short-term efficacy on depressive symptoms. Post hoc analyses indicated that there may be a significant but transient effect in certain populations. Further studies should focus on identifying subgroups of responders as well as examining feasibility in routine clinical care.

Association between exposure to toxoplasmosis and major psychiatric disorders: a systematic review

Objective:

To assess the association between exposure to toxoplasmosis and major psychiatric disorders through a systematic review of the literature.

Methods:

The literature review was performed in the MEDLINE, SciELO, and PsycINFO databases. To evaluate the quality of the studies included in the review, the Newcastle-Ottawa Scale was used.

Results:

Thirty-one studies were included, and the majority found an association between exposure to toxoplasmosis and schizophrenia or bipolar disorder (58.3 and 54.5% of the included papers, respectively), but not major depressive disorder. We found no significant difference in mean quality scores between studies that corroborated and contradicted the association hypothesis for either schizophrenia or bipolar disorder. All included papers were considered at least satisfactory according to the Newcastle-Ottawa Scale (total scores ≥ 6 out of 9).

Conclusion:

Although there was no association between exposure to toxoplasmosis and major depressive disorder, the results indicate an association with both bipolar disorder and schizophrenia, despite their heterogeneity. Further studies should be performed with more specific variables so that the nature of these relationships can be elucidated.

Exercise is medicine: a new perspective for health promotion in bipolar disorder

INTRODUCTION

Similar effects in reducing the symptoms of the mood disorder are reported in the literature compared the action of drugs and aerobic exercise sessions, demonstrating the potential of exercise in the control and mood stabilization. Therefore, there are many reasons to believe that the increased cardiorespiratory fitness (VO_2max) can be an important means of protection and a reducing potential of physical and mental damage in bipolar disorders (BD). This review will highlight the current pattern of response of exercise on the pathophysiology of BD, relating the possible mechanisms, and hypotheses based on exercises.

AREAS COVERED

The mechanism of monoaminergic action and its relationship with exercise, role of physical conditioning and increased VO_2Max on neurotrophin release, and new perspectives on long-term exercise will be reviewed.

EXPERT OPINION

The adaptations to training, although little explored in the context of BD, can induce the expression of substances that co-regulate several processes related to the pathophysiology of BD. Furthermore, high intensity interval training (HIIT) can also be adjusted to improve the physical fitness and health in patients with BD. Future research is needed to adopt a training strategy that is both time efficient and adequate for the population in question.

Urinary metabolite signature in bipolar disorder patients during depressive episode

The first few episodes of bipolar disorder (BD) are highly likely to be depressive. This phenomenon causes many BD patients to be misdiagnosed as having major depression. Therefore, it is very important to correctly diagnose BD patients during depressive episode. Here, we conducted this study to identify potential biomarkers for young and middle-aged BD patients during depressive episode. Both gas chromatography-mass spectroscopy (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy were used to profile the urine samples from the recruited subjects. In total, 13 differential metabolites responsible for the discrimination between healthy controls (HCs) and patients were identified. Most differential metabolites had a close relationship with energy homeostasis. Meanwhile, a panel consisting of five differential metabolites was identified. This panel could effectively distinguish the patients from HCs with an AUC of 0.998 in the training set and 0.974 in the testing set. Our findings on one hand could be helpful in developing an objective diagnostic method for young and middle-aged BD patients during depressive episode; on the other hand could provide critical insight into the pathological mechanism of BD and the biological mechanisms responsible for the transformation of different episodes.

Ketamine in Bipolar Disorder: A Review

Bipolar disorder (BD) is a psychiatric illness associated with high morbidity, mortality and suicide rate. It has neuroprogressive course and a high rate of treatment resistance. Hence, there is an unquestionable need for new BD treatment strategies. Ketamine appears to have rapid antidepressive and antisuicidal effects. Since most of the available studies concern unipolar depression, here we present a novel insight arguing that ketamine might be a promising treatment for bipolar disorder.

Affective Switch Associated With Oral, Low Dose Ketamine Treatment in a Patient With Treatment Resistant Bipolar I Depression. Case Report and Literature Review

There is a growing evidence for the rapid and robust antidepressive effect of ketamine in unipolar and bipolar treatment resistant depression although evidence for the risk of affective switch is still limited. This case presents bipolar I disorder patient with treatment resistant depressive episode experiencing a switch to manic episode with mixed features shortly after receiving eight subanaesthetic doses of oral ketamine as an add-on treatment preceded by 2-day period of manic symptoms.

Repetitive Transcranial Magnetic Stimulation in the Treatment of Bipolar Depression: Experience From a Clinical Setting

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive Food and Drug Administration (FDA)-approved treatment for unipolar treatment-resistant depression (TRD). rTMS has been utilized clinically to treat bipolar TRD; however, there remains a lack of evidence and support for effectively utilizing this intervention for bipolar TRD. We retrospectively analyzed data from a group of patients who were treated with rTMS for unipolar or bipolar TRD and describe a case example to further delineate management techniques for employing rTMS in the treatment of bipolar TRD.

METHODS

Records of 71 patients treated with rTMS for unipolar (n=54) or bipolar (n=17) TRD between 2008 and 2017 were reviewed. The primary outcome of depression severity, the Quick Inventory of Depressive Symptomatology, was completed at baseline and after every 5 sessions throughout the course of 30 treatments. Secondary outcomes involved a comparison of outcomes and clinical characteristics within and between the bipolar and unipolar TRD groups.

RESULTS

In the total sample, patients' depression improved significantly over the course of treatment. Patients with bipolar TRD showed greater response and remission rates over the course of treatment compared with patients with unipolar TRD, but this difference was not statistically significant. Both groups showed a similar pattern of depression response over treatment time. No manic or hypomanic episodes occurred during any patient's course of rTMS treatment. A case example is provided discussing the timing of rTMS in a patient with bipolar depression to decrease the likelihood of treatment-induced hypomania.

LIMITATIONS

Limitations included the small overall sample size, the smaller size of the patient group with bipolar TRD compared with the group with unipolar TRD, and the naturalistic setting of this study.

CONCLUSIONS

Our data suggest that rTMS may be equally effective and safe for patients with both unipolar and bipolar depression. Patients with bipolar TRD showed a similar response profile over treatment time compared with patients with unipolar TRD.