The hypothalamic-pituitary-adrenal axis and serotonin abnormalities: a selective overview for the implications of suicide prevention

Early life stress unravels epistatic genetic associations of cortisol pathway genes with depression

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis represents one of the most consistent pathophysiological findings in depressive disorders. Cortisol signaling is affected by proteins that mediate its cellular responses or alters its availability to mineralocorticoid and glucocorticoid receptors. In our study, we evaluated candidate genes that may influence the risk for depression and suicide due to its involvement in cortisol signaling. The aim of the study was to assess whether the genotypes of these genes are associated with the risk for depression, severity of depressive symptoms, suicidal ideation, and suicide attempts. And whether there is interaction between genes and early-life stress. In this study, 100 healthy controls and 140 individuals with depression were included. The subjects were clinically assessed using the 21-item GRID-Hamilton questionnaires (GRID-HAMD-21), Beck Scale for Suicidal Ideation (BSI), and the Childhood Trauma Questionnaire (CTQ). A robust multifactorial dimensionality reduction analysis was used to characterize the interactions between the genes HSD11B1, NR3C1, NR3C2, and MDR1 and early-life stress. It was found a significant association of the heterozygous genotype of the MDR1 gene rs1128503 polymorphism with reduced risk of at least one suicide attempt (OR: 0.08, p = 0.003*) and a reduction in the number of suicide attempts (β = -0.79, p = 0.006*). Furthermore, it was found that the MDR1 rs1228503 and NR3C2 rs2070951 genes interact with early-life stress resulting in a strong association with depression (p = 0.001). Our findings suggest that polymorphisms in the MDR1 and NR3C2 genes and their interaction with childhood trauma may be important biomarkers for depression and suicidal behaviors.

Inter-relationships between suicidality and depressive symptoms among children and adolescents experiencing crisis: A network perspective

OBJECTIVES

Suicidality and depressive symptoms have emerged as major mental health issues reported among children and adolescents experiencing crises. In light of these concerns, this study was conducted to elucidate interrelationships between depressive symptoms and suicidality at an item level within this population during the COVID-19 pandemic, a worldwide public health crisis affecting children and adolescents.

METHOD

A cross-sectional study design was used. Primary and secondary school students completed the Children's Depression Inventory - Short Version (CDI-S) and two standard suicidality questions tapping suicidal ideation and suicide plans, respectively. A network analysis was performed to examine inter-connections between depressive symptoms and suicidality.

RESULTS

A total of 5380 students participated in the study. Prevalence of suicidal ideation and suicide plans were 12.8 % (95 % CI = 11.9 %-13.7 %) and 9.9 % (95 % CI = 9.2 %-10.8 %), respectively; the prevalence of depressive symptoms was 41.2 % (95%CI = 39.8 %-42.5 %). The network analysis identified CDI4 (self-hatred) as the most influential node with the highest centrality, followed by CDI8 (loneliness), CDI5 (crying), and CDI1 (sadness). Additionally, CDI5 (crying), CDI1 (sadness), CDI4 (self-hatred), and CDI10 (feeling unloved) were the most meaningful nodes linking depressive symptoms with suicidality.

CONCLUSIONS

Critical depressive symptoms linked with suicidality among children and adolescents living through the COVID-19 pandemic included self-hatred, loneliness, crying, and sadness. Interventions that target these depressive symptoms may have increased utility in reducing the risk of suicidality within this population.

Stress and the CRH System, Norepinephrine, Depression, and Type 2 Diabetes

Major depressive disorder (MDD) increases the risk of type 2 diabetes (T2D) by 60% in untreated patients, and hypercortisolism is common in MDD as well as in some patients with T2D. Patients with MDD, despite hypercortisolism, show inappropriately normal levels of corticotropin-releasing hormone (CRH) and plasma adrenocorticotropin (ACTH) in the cerebrospinal fluid, which might implicate impaired negative feedback. Also, a positive feedback loop of the CRH-norepinephrine (NE)-CRH system may be involved in the hypercortisolism of MDD and T2D. Dysfunctional CRH receptor 1 (CRHR1) and CRH receptor 2 (CRHR2), both of which are involved in glucose regulation, may explain hypercortisolism in MDD and T2D, at least in a subgroup of patients. CRHR1 increases glucose-stimulated insulin secretion. Dysfunctional CRHR1 variants can cause hypercortisolism, leading to serotonin dysfunction and depression, which can contribute to hyperglycemia, insulin resistance, and increased visceral fat, all of which are characteristics of T2D. CRHR2 is implicated in glucose homeostasis through the regulation of insulin secretion and gastrointestinal functions, and it stimulates insulin sensitivity at the muscular level. A few studies show a correlation of the CRHR2 gene with depressive disorders. Based on our own research, we have found a linkage and association (i.e., linkage disequilibrium [LD]) of the genes CRHR1 and CRHR2 with MDD and T2D in families with T2D. The correlation of CRHR1 and CRHR2 with MDD appears stronger than that with T2D, and per our hypothesis, MDD may precede the onset of T2D. According to the findings of our analysis, CRHR1 and CRHR2 variants could modify the response to prolonged chronic stress and contribute to high levels of cortisol, increasing the risk of developing MDD, T2D, and the comorbidity MDD-T2D. We report here the potential links of the CRH system, NE, and their roles in MDD and T2D.

Suicidal ideation, attempt, and its associated factors among adult HIV/AIDS patients in Ethiopia: A systematic review and meta-analysis study

BACKGROUND

WHO statistics show that someone attempts suicide every three seconds and commits suicide every 40 seconds somewhere in the world. There is a scarcity of aggregate evidence in Ethiopia. The aim of this review was to assess the pooled prevalence of suicidal ideation, attempts, and associated factors among adult HIV/AIDS patients in Ethiopia to fill this gap.

METHODS

We extensively searched the bibliographic databases of PubMed, MEDLINE, Scopus, Google Scholar, and the Web of Science to obtain eligible studies. Further screening for a reference list of articles was also done. The Microsoft Excel Spreadsheet was used to extract data, and Stata 17 was used for analysis. To check heterogeneity, the Higgs I2 and Cochran's Q tests were employed. Sensitivity and subgroup analysis were implemented. To detect publication bias, Egger's test and funnel plots were used.

RESULTS

The pooled prevalence of suicidal ideation and attempts among adult HIV/AIDS patients in Ethiopia was 20.3 with a 95% CI (14, 26.5) and 11.1 with a 95% CI (6.6, 15.5), respectively. Living alone (AOR 4.98; 95% CI: 2.96-8.37), having comorbidity or other opportunistic infection (AOR 4.67; 95% CI: 2.57-8.48), female sex (AOR 2.86; 95% CI: 1.76, 4.62), having WHO clinical stage III of HIV (AOR 3.69; 95% CI: 2.15, 6.32), having WHO clinical stage IV of HIV (AOR 5.43; 95% CI: 2.81, 10.53), having co-morbid depression (AOR 5.25; 95% CI: 4.05, 6.80), having perceived HIV stigma (AOR 2.53; 95% CI: 1.67, 3.84), and having family history of suicidal attempt (AOR 2.79; 95% CI: 1.38, 5.66) were significantly associated with suicidal ideation. Being female (AOR 4.33; 95% CI: 2.36, 7.96), having opportunistic infections (AOR 2.73; 95% CI: 1.69, 4.41), having WHO clinical stage III of HIV (AOR 3.78; 95% CI: 2.04, 7.03), having co-morbid depression (AOR 3.47; 95% CI: 2.38, 5.05), having poor social support (AOR 3.02; 95% CI: 1.78, 5.13), and having WHO clinical stage IV (AOR 7.39; 95% CI: 3.54, 15.41) were significantly associated with suicidal attempts.

CONCLUSION

The pooled magnitude of suicidal ideation and attempt was high, and factors like opportunistic infection, WHO clinical stage III of HIV, WHO clinical stage III of HIV, and co-morbid depression were related to both suicidal ideation and attempt. Clinicians should be geared towards this mental health problem in HIV patients during management.

Psychosocial stress, adult suicidal ideation, and the mediating effect of poor sleep quality during the COVID-19 pandemic in South Africa

OBJECTIVES

South Africa instituted one of the world's strictest lockdowns during the COVID-19 pandemic, which generated heightened conditions of psychosocial stress and posed widespread mental health risks. Despite the elevated burdens of suicidal behaviors and risk of psychiatric disease in the country, few studies have examined the impacts of psychosocial stress from the pandemic on suicidal ideation in South Africa. This study examined the association between psychosocial stress experienced under the COVID-19 pandemic and adult suicidal ideation, as well as degree to which sleep quality and duration mediated this relationship.

METHODS

An online survey assessed experiences of COVID-19 psychosocial stress, sleep quality and duration, and suicidal ideation in a sample of 189 South African adults during the second and third waves of the COVID-19 pandemic. A causal inference framework for mediation analysis was used to assess the degree to which sleep quality and duration explained the association between COVID-19 psychosocial stress and suicidal ideation.

RESULTS

Suicidal ideation was reported in 21% of adults. Adults described having moderate sleep quality and an average of 6.9 hours of sleep per night. COVID-19 psychosocial stress significantly predicted adult suicidal ideation in fully adjusted models. Sleep quality, but not sleep duration, significantly mediated the association between COVID-19 psychosocial stress and suicidal ideation, accounting for 25.9% of the total effect.

CONCLUSIONS

Poor sleep quality may play an important role in exacerbating the alarming stress-induced mental health effects of the COVID-19 pandemic. Further research is necessary to understand the underlying sleep dynamics and associated psychological and neurobiological processes that perpetuate adult suicidal ideation.

Neuroinflammation, memory, and depression: new approaches to hippocampal neurogenesis

As one of most common and severe mental disorders, major depressive disorder (MDD) significantly increases the risks of premature death and other medical conditions for patients. Neuroinflammation is the abnormal immune response in the brain, and its correlation with MDD is receiving increasing attention. Neuroinflammation has been reported to be involved in MDD through distinct neurobiological mechanisms, among which the dysregulation of neurogenesis in the dentate gyrus (DG) of the hippocampus (HPC) is receiving increasing attention. The DG of the hippocampus is one of two niches for neurogenesis in the adult mammalian brain, and neurotrophic factors are fundamental regulators of this neurogenesis process. The reported cell types involved in mediating neuroinflammation include microglia, astrocytes, oligodendrocytes, meningeal leukocytes, and peripheral immune cells which selectively penetrate the blood-brain barrier and infiltrate into inflammatory regions. This review summarizes the functions of the hippocampus affected by neuroinflammation during MDD progression and the corresponding influences on the memory of MDD patients and model animals.

Visuospatial ability and attention as risk factors for suicidal ideation in middle-aged and elderly schizophrenia patients: a cross-sectional study

BACKGROUND

Schizophrenia patients have a high risk of suicide, and their cognition function is impaired with increasing age. The association between neurocognitive and suicidality in schizophrenia patients are heterogeneous. We aimed to explore the relationship between neurocognitive function and suicidal ideation in schizophrenia patients across age groups.

METHODS

A total of 587 patients with schizophrenia were enrolled in this study. The schizophrenia patients were divided into young group (aged 18-44) and middle-aged and elderly group (aged 45-70). The schizophrenia patients were divided into suicidal ideation group and non-suicidal ideation group according to the evaluation results of the Beck Scale for Suicide Ideation. Insomnia symptoms were measured by the Insomnia Severity Index (ISI). Psychotic symptoms were measured by the Positive and Negative Syndrome Scale (PANSS), and cognitive function was measured by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

RESULTS

There was a negative correlation between the age and attention scores of RBANS (P = 0.018). The young schizophrenia patients had higher risk of suicidality than middle-aged and elderly schizophrenia patients (P = 0.001). In the logistic regression analysis, the scores of ISI and positive symptoms scores of PANSS were associated with suicidal ideation among young schizophrenia patients (All P < 0.05). Age, BMI, the scores of ISI, general symptoms scores of PANSS, visuospatial scores of RBANS and attention scores of RBANS were associated with suicidal ideation in middle-aged and elderly schizophrenia patients (All P < 0.05).

CONCLUSIONS

High visuospatial scores of RBANS and attention scores of RBANS were risk factors for suicidal ideation in middle-aged and elderly schizophrenia patients.

Vasopressin as Possible Treatment Option in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is rather common, presenting with prevalent early problems in social communication and accompanied by repetitive behavior. As vasopressin was implicated not only in salt-water homeostasis and stress-axis regulation, but also in social behavior, its role in the development of ASD might be suggested. In this review, we summarized a wide range of problems associated with ASD to which vasopressin might contribute, from social skills to communication, motor function problems, autonomous nervous system alterations as well as sleep disturbances, and altered sensory information processing. Beside functional connections between vasopressin and ASD, we draw attention to the anatomical background, highlighting several brain areas, including the paraventricular nucleus of the hypothalamus, medial preoptic area, lateral septum, bed nucleus of stria terminalis, amygdala, hippocampus, olfactory bulb and even the cerebellum, either producing vasopressin or containing vasopressinergic receptors (presumably V1a). Sex differences in the vasopressinergic system might underline the male prevalence of ASD. Moreover, vasopressin might contribute to the effectiveness of available off-label therapies as well as serve as a possible target for intervention. In this sense, vasopressin, but paradoxically also V1a receptor antagonist, were found to be effective in some clinical trials. We concluded that although vasopressin might be an effective candidate for ASD treatment, we might assume that only a subgroup (e.g., with stress-axis disturbances), a certain sex (most probably males) and a certain brain area (targeting by means of virus vectors) would benefit from this therapy.

Structural and functional brain correlates of suicidal ideation and behaviors in depression: A scoping review of MRI studies

Identifying and integrating the neural correlates of suicidal ideation and behaviors is crucial to expand the knowledge and develop targeted strategies to prevent suicide. This review aimed to describe the neural correlates of suicidal ideation, behavior and the transition between them, using different magnetic resonance imaging (MRI) modalities, providing an up-to-date overview of the literature. To be included, the observational, experimental, or quasi-experimental studies must include adult patients currently diagnosed with major depressive disorder and investigate the neural correlates of suicidal ideation, behavior and/or the transition using MRI. The searches were conducted on PubMed, ISI Web of Knowledge and Scopus. Fifty articles were included in this review: 22 on suicidal ideation, 26 on suicide behaviors and two on the transition between them. The qualitative analysis of the included studies suggested alterations in the frontal, limbic and temporal lobes in suicidal ideation associated with deficits in emotional processing and regulation, and in the frontal, limbic, parietal lobes, and basal ganglia in suicide behaviors associated with impairments in decision-making. Gaps in the literature and methodological concerns were identified and might be addressed in future studies.

Pathways from childhood trauma to suicidal ideation: mediating through difficulties in emotion regulation and depressive symptoms

OBJECTIVE

Suicidal ideation is a clinical exigency heightening the risk of suicide at different levels of suicidal behavior. This study sought to explore crucial correlates of this phenomenon with a structural equation modeling approach. Accordingly, the mediating role of depressive symptoms and difficulties in emotion regulation between childhood trauma and suicidal ideation were explored.

METHOD

The sample consisted of 372 university students (57.3% females, M = 20.75, SD = 2.25) who completed self-report measures examining experiences of childhood trauma, depressive symptoms, difficulties in emotion regulation, and suicidal ideation. Structural equation modeling was employed, and mediation analysis was conducted. Confirmatory factor analysis was used to test the measurement model of each construct before evaluating the conceptual mediated model.

RESULTS

Findings indicate that depressive symptoms with difficulties in emotion regulation had the strongest association (r = 0.60, P = 0.001), then depressive symptoms and suicidal ideation (r = 0.58, P = 0.001), suicidal ideation with difficulties in emotion regulation (r = 0.45, P = 0.001) then suicidal ideation with childhood trauma (r = 0.39, P = 0.001), difficulties in emotion regulation with childhood trauma (r = 0.36 P = 0.001) and finally depressive symptoms and childhood trauma (r = 0.35, P = 0.001). Regarding indirect paths, difficulties in emotion regulation and depression function together (in a sequential path) to mediate the association between childhood trauma and suicidal ideation ( χ²(68) = 216.86, P < 0.01, CFI = 0.95, TLI = 0.93, RMSE = 0.077, CI [0.066 to 0.089], SRMR = 0.049).

CONCLUSION

Results demonstrate that childhood trauma, depressive symptoms, and difficulties in emotion regulation are linked to suicidal ideation, highlighting the necessity of recognizing and addressing suicidal ideation as well as the factors that contribute to suicidal ideation. Emotion regulation interventions can be effective in reducing the negative effects of childhood trauma and lowering the risk of suicide. These interventions can help in reducing depressive symptoms and improve overall mental well-being, leading to a lower risk of suicide.

Association of metabolic syndrome and its components with the risk of depressive symptoms: A systematic review and meta-analysis of cohort studies

BACKGROUND

The purpose of this meta-analysis was to quantitatively analyze the association between metabolic syndrome (MetS) and the risk of depressive symptoms.

METHODS

Three electronic databases (PubMed, Embase, and PsycINFO) were searched for articles published through February 15, 2022. Cohort studies evaluating the association between MetS and depressive symptoms were selected for inclusion in this study. A random-effects model was used to evaluate the pooled estimates of MetS, including each of its components, associated with depressive symptoms.

RESULTS

A total of 11 cohort studies were selected including >2.65 million participants. There was a significant association between MetS and depressive symptoms risk, albeit with a high degree of heterogeneity (relative risk = 1.29, 95 % confidence interval: 1.12-1.48; I2 = 79.3 %). This association was consistently significant in Western countries, but it was not significant in Asian countries. When stratified by sex, age, and geographical region, MetS and its components exhibited varying degrees of association with depressive symptoms.

CONCLUSIONS

MetS is a risk factor for depressive symptoms. Further large-scale prospective cohort studies are required to confirm our findings.

The Serotonergic System and Amyotrophic Lateral Sclerosis: A Review of Current Evidence

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by the premature death of motor neurons. Serotonin (5-HT) is a crucial neurotransmitter, and its dysfunction, whether as a contributor or by-product, has been implicated in ALS pathogenesis. Here, we summarize current evidence linking serotonergic alterations to ALS, including results from post-mortem and neuroimaging studies, biofluid testing, and studies of ALS animal models. We also discuss the possible role of 5-HT in modulating some important mechanisms of ALS (i.e. glutamate excitotoxity and neuroinflammation) and in regulating ALS phenotypes (i.e. breathing dysfunction and metabolic defects). Finally, we discuss the promise and limitations of the serotonergic system as a target for the development of ALS biomarkers and therapeutic approaches. However, due to a relative paucity of data and standardized methodologies in previous studies, proper interpretation of existing results remains a challenge. Future research is needed to unravel the mechanisms linking serotonergic pathways and ALS and to provide valid, reproducible, and translatable findings.

The Role of Inflammation in the Pathophysiology of Depression and Suicidal Behavior: Implications for Treatment

Depression and suicidal behavior are 2 complex psychiatric conditions of significant public health concerns due to their debilitating nature. The need to enhance contemporary treatments and preventative approaches for these illnesses not only calls for distillation of current views on their pathogenesis but also provides an impetus for further elucidation of their novel etiological determinants. In this regard, inflammation has recently been recognized as a potentially important contributor to the development of depression and suicidal behavior. This review highlights key evidence that supports the presence of dysregulated neurometabolic and immunologic signaling and abnormal interaction with microbial species as putative etiological hallmarks of inflammation in depression as well as their contribution to the development of suicidal behavior. Furthermore, therapeutic insights addressing candidate mechanisms of pathological inflammation in these disorders are proposed.

A molecular framework for autistic experiences: Mitochondrial allostatic load as a mediator between autism and psychopathology

Molecular autism research is evolving toward a biopsychosocial framework that is more informed by autistic experiences. In this context, research aims are moving away from correcting external autistic behaviors and toward alleviating internal distress. Autism Spectrum Conditions (ASCs) are associated with high rates of depression, suicidality and other comorbid psychopathologies, but this relationship is poorly understood. Here, we integrate emerging characterizations of internal autistic experiences within a molecular framework to yield insight into the prevalence of psychopathology in ASC. We demonstrate that descriptions of social camouflaging and autistic burnout resonate closely with the accepted definitions for early life stress (ELS) and chronic adolescent stress (CAS). We propose that social camouflaging could be considered a distinct form of CAS that contributes to allostatic overload, culminating in a pathophysiological state that is experienced as autistic burnout. Autistic burnout is thought to contribute to psychopathology via psychological and physiological mechanisms, but these remain largely unexplored by molecular researchers. Building on converging fields in molecular neuroscience, we discuss the substantial evidence implicating mitochondrial dysfunction in ASC to propose a novel role for mitochondrial allostatic load in the relationship between autism and psychopathology. An interplay between mitochondrial, neuroimmune and neuroendocrine signaling is increasingly implicated in stress-related psychopathologies, and these molecular players are also associated with neurodevelopmental, neurophysiological and neurochemical aspects of ASC. Together, this suggests an increased exposure and underlying molecular susceptibility to ELS that increases the risk of psychopathology in ASC. This article describes an integrative framework shaped by autistic experiences that highlights novel avenues for molecular research into mechanisms that directly affect the quality of life and wellbeing of autistic individuals. Moreover, this framework emphasizes the need for increased access to diagnoses, accommodations, and resources to improve mental health outcomes in autism.

Serotonin in the regulation of systemic energy metabolism

Serotonin is a well‐known neurotransmitter that is synthesized from the amino acid, tryptophan. To date, more than 14 different serotonin receptors have been discovered; they exist universally in our body and enable diverse biological functions in different organs. Central serotonin regulates mood and behavior, and impacts the systemic energy balance by decreasing appetite. A number of drugs that modulate central serotonin function (e.g., fenfluramine, sibutramine and lorcaserin) were approved and used as anti‐obesity drugs, but then later withdrawn due to adverse cardiovascular and carcinogenic effects. Over the past decade, the role of peripheral serotonin in regulating systemic energy metabolism has been extensively explored using tissue‐specific knockout animal models. By inhibiting the action of serotonin in liver and adipose tissues, hepatic steatosis was improved and lipid accumulation was mitigated, respectively. Recent findings show that modulation of the serotonergic system is a promising therapeutic target for metabolic diseases. This review summarizes the role of serotonin in regulating energy metabolism in different organs, and discusses the potential of serotonin modulation for treating metabolic diseases.

Suicide: Allostatic regulation and resilience

Suicide is a complex public health problem that is the result of a number of intertwined biopsychosocial factors. The diathesis-stress model suggests that suicide is the result of an interaction between genetic vulnerability and environmental stressors. Chronic stress and trauma contribute to biologic adaptations, including hypothalamus-pituitary-adrenal axis dysregulation, that contribute to the degradation of regulatory mechanisms and promote wear and tear the body, represented by allostatic load (AL). AL has been associated with a number of negative outcomes, including mental health problems and suicide. Fortunately, there are pharmacological and non-pharmacological interventions that are effective at reducing AL and reversing its effects. Thus, AL may provide a construct for supporting early risk identification, prevention, and treatment of suicide. AL biomarkers that are amenable to measurable change, effective treatments to reduce AL and perhaps help prevent suicide, and how to best tailor them to the individual and societal levels are important avenues of therapeutic inquiry.

Suicide Biomarkers to Predict Risk, Classify Diagnostic Subtypes, and Identify Novel Therapeutic Targets: 5 Years of Promising Research

BACKGROUND

Suicide is a global health crisis. However, no objective biomarkers of suicide risk currently exist, and self-reported data can be unreliable, which limits prediction, diagnostic, and treatment efforts. Reliable biomarkers that can differentiate between diagnostic subgroups, predict worsening symptoms, or suggest novel therapeutic targets would be extremely valuable for patients, researchers, and clinicians.

METHODS

MEDLINE was searched for reports published between 2016 and 2021 using search terms (suicid*) AND (biomarker*) OR (indicat*). Reports that compared biomarkers between suicidal ideation, suicide attempt, death from suicide, or any suicide subgroup against other neuropsychiatric disorders were included. Studies exclusively comparing suicidal behavior or death from suicide with healthy controls were not included to ensure that biomarkers were specific to suicide and not other psychopathology.

RESULTS

This review summarizes the last 5 years of research into suicide-associated biomarkers and provides a comprehensive guide for promising and novel biomarkers that encompass varying presentations of suicidal ideation, suicide attempt, and death by suicide. The serotonergic system, inflammation, hypothalamic-pituitary-adrenal axis, lipids, and endocannabinoids emerged as the most promising diagnostic, predictive, and therapeutic indicators.

CONCLUSIONS

The utility of diagnostic and predictive biomarkers is evident, particularly for suicide prevention. While larger-scale studies and further in-depth research are required, the last 5 years of research has uncovered essential biomarkers that could ultimately improve predictive strategies, aid diagnostics, and help develop future therapeutic targets.

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.

Possible Association of Cholesterol as a Biomarker in Suicide Behavior

Suicides and suicidal behavior are major causes of mortality and morbidity in public health and are a global problem. Various authors have proposed changes in lipid metabolism (total cholesterol decrease) as a possible biological marker for suicidal behavior. The objective of this study was to review the studies that have demonstrated a relationship between serum cholesterol levels and suicidal behavior and to describe the possible pathophysiological mechanisms that associate changes in cholesterol concentration and suicidal behavior. Relevant literature related to serum cholesterol levels and suicidal behavior was identified through various database searches. The data from the existing literature present the findings that relate low cholesterol levels and possible pathophysiological mechanisms (neuroinflammation, serotonergic neurotransmission), genes related to cholesterol synthesis, pharmacological treatments that alter lipid metabolism and the possible participation in suicidal behavior. Nevertheless, future research is required to describe how serum cholesterol affects cholesterol metabolism in the CNS to establish and understand the role of cholesterol in suicidal behavior.

Exploring the link between adolescent inhalant misuse and suicidal behaviour: a behavioural toxicology perspective

Adolescent inhalant misuse has a known association with suicidal thoughts and behaviour. This association persists even after inhalant misuse has ceased. Previous studies have hypothesised that this association may derive from socioeconomic disadvantage or vulnerability, and potentially mediated by impulsivity. This association may also be due to the central nervous system depressant effects of inhalants. This review takes a behavioural toxicology perspective, focussed particularly on the serotonergic system and the Hypothalamic-Pituitary-Adrenal (HPA) axis, as potential links between adolescent inhalant misuse and suicidal behaviour. The challenges of bridging the pre-clinical and clinical literature in this area are discussed, along with promising avenues for future research; ultimately aimed at reducing suicide risk in a vulnerable adolescent population group.

Neurobiological Basis of Increased Risk for Suicidal Behaviour

According to the World Health Organization (WHO), more than 700,000 people die per year due to suicide. Suicide risk factors include a previous suicide attempt and psychiatric disorders. The highest mortality rate in suicide worldwide is due to depression. Current evidence suggests that suicide etiopathogenesis is associated with neuroinflammation that activates the kynurenine pathway and causes subsequent serotonin depletion and stimulation of glutamate neurotransmission. These changes are accompanied by decreased BDNF (brain-derived neurotrophic factor) levels in the brain, which is often linked to impaired neuroplasticity and cognitive deficits. Most suicidal patients have a hyperactive hypothalamus–pituitary–adrenal (HPA) axis. Epigenetic mechanisms control the above-mentioned neurobiological changes associated with suicidal behaviour. Suicide risk could be attenuated by appropriate psychological treatment, electroconvulsive treatment, and drugs: lithium, ketamine, esketamine, clozapine. In this review, we present the etiopathogenesis of suicide behaviour and explore the mechanisms of action of anti-suicidal treatments, pinpointing similarities among them.

The role of rs242941, rs1876828, rs242939 and rs110402 polymorphisms of CRHR1 gene and the depression: systematic review and meta-analysis

BACKGROUND

Several studies have evaluated the possible association between polymorphisms or variants in Corticotropin-releasing hormone 1 receptor gene (CRHR1) with depression; however, results remain contradictory and heterogeneous.

OBJECTIVE

To our knowledge, we conducted the first comprehensive systematic review and meta-analysis evaluating the association of the CRHR1 gene and the risk of depression.

METHODS

A search online was conducted in databases for any CRHR1 genetic association studies in depression. Data were extracted for evaluation of pooled estimates using meta-analytic techniques. Statistical analyses were performed using the Comprehensive Meta-analysis, v2.0 software.

RESULT

A total of 1403 cases and 2353 mentally healthy controls were included in this study. We found a significant association of rs242941, rs1876828 and rs242939 variants of the CRHR1 gene with depression. No association of CRHR1 rs110402 and depression was observed.

CONCLUSION

Our meta-analysis shows that some variants of the CRHR1 gene (rs242941, rs1876828 and rs242939) might confer susceptibility to depression. Further studies with larger sample sizes need to be conducted.

Incidence rate and risk factors for suicide death in patients with skin malignant melanoma: a Surveillance, Epidemiology, and End Results analysis

The purpose of this study was to use the Surveillance, Epidemiology, and End Results database to identify the incidence rate and risk factors for suicide death in patients with skin malignant melanoma (MM) in the USA. We screened cases of skin MM in the SEER database. The balance of covariates between the two groups was examined by the χ-test and Fisher's exact test. Logistic regression was used to identify independent risk factors for committing suicide. A propensity 1: 2 matched analysis was applied to minimize the risk of bias. In total, 103 500 patients with skin MM were included in the study, of whom 623 had died of suicide. The rate of suicide death did not differ significantly between different time intervals. In logistic regression before propensity score matching, age, being divorced, separated, or widowed, receiving radiation or chemotherapy, and the elapsed time since diagnosis were independently associated with an increased rate of suicide death. Only age (P  <  0.001) and being in the first year after a diagnosis (P  <  0.001) significantly increased the risk of suicide death after propensity score matching. In addition, after the propensity score matching, age was a risk factor for localized, regional, and unstaged, and being the first year after a diagnosis was only a risk factor for regional. It is important to identify and treat people at risk of suicide as early as possible. These results can help clinicians to understand suicidal patients and provide them with appropriate support.

Trait anxiety, a personality risk factor associated with Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative disease in elderly population and the leading cause of dementia worldwide. While senile plaques and neurofibrillary tangles have been proposed as the principal histopathologic hallmarks of AD, the exact etiology of this disease is still far from being clearly understood. AD has been recognized as pathological consequences of complex interactions among genetic, aging, medical, life style and psychosocial factors. Recently, the roles of neuroticism personality traits in AD incidence and progression have come into focus. More specifically, increasing evidence has further shown that the trait anxiety, one major component of neuroticism predicting the individual vulnerability in response to stress, is a risk factor for AD and may correlated with various AD pathologies. In this review, we summarized recent literature on the association of trait anxiety with AD. We also discussed the possible neuroendocrinological and neurochemical mechanisms of this association, which may provide clinical implications for AD diagnosis and therapy.

A Load to Find Clinically Useful Biomarkers for Depression

Depression is heterogeneous and complex disease with diverse symptoms. Its neurobiological underpinning is still not completely understood. For now, there are still no validated, easy obtainable, clinically useful noninvasive biomarker(s) or biomarker panel that will be able to confirm a diagnosis of depression, its subtypes and improve diagnostic procedures. Future multimodal preclinical and clinical research that involves (epi)genetic, molecular, cellular, imaging, and other studies is necessary to advance our understanding of the role of monoamines, GABA, HPA axis, neurotrophins, metabolome, and glycome in the pathogenesis of depression and their potential as diagnostic, prognostic, and treatment response biomarkers. These studies should be focused to include the first-episode depression and antidepressant drug-naïve patients with large sample sizes to reduce variability in different biological and clinical parameters. At present, metabolomics study revealed with high precision that a neurometabolite panel consisting of plasma metabolite biomarkers (GABA, dopamine, tyramine, kynurenine) might represent clinically useful biomarkers of MDD.

Social and Biological Parameters Involved in Suicide Ideation During the COVID-19 Pandemic: A Narrative Review

Fear is an indispensable characteristic of any infectious disease, and the alarm will be further amplified when the infection spreads uncontrollable, unpredictable, and global. The novel corona virus (SARS CoV-2) lead Covid-19, has been declared as a global emergency by WHO as it has affected millions of people with a high mortality rate. The non-availability of medicine for Covid-19 and the various control measures such as social distancing, self-isolation, house quarantine, and the new normal implementation by different nations across the world to control the spread of Covid-19 made people vulnerable to fear and anxiety. As a result, considerable number of Covid-19-related suicidal deaths has been reported across the world during this pandemic. There have been several studies which describe the psychosocial aspects of suicidal ideation. However, the research on the biological aspects of suicidal ideation/suicidal risk factors that are related to pandemic are unreported. Hence this review article is intended to provide a comprehensive analysis of suicidal deaths during Covid-19 and also aimed to addresses the possible link between suicidal ideation and different factors, including psycho-social, behavioral, neurobiological factors (proximal, distal, and inflammatory) and immunity. The alterations in glutamatergic and GABAergic neurotransmitters had upregulated the GABARB3, GABARA4, GABARA3, GABARR1, GABARG2, and GAD2 gene expressions in suicidal victims. The changes in the Kynurenine (KYN) pathway, Hypothalamus-Pituitary-Adrenal axis (HPA axis) hyperactivation, and dysregulation of serotonin biosynthesis would significantly alter the brain chemistry in people with suicide ideation.

Harms associated with inhalant misuse in adolescent females - a review of the pre-clinical and clinical evidence

BACKGROUND

Inhalant misuse, or the misuse of products containing toluene is common in adolescents, and is associated with diverse physiological and psychological harms. Females comprise over half those who misuse inhalants in adolescence, however, the majority of the evidence has been derived from male-only or mixed-sex studies without exploration of sex differences. Female adolescence is a critical maturational period with potential for growth, reproductive, cognitive and psychological harms that may lead to long-term health consequences. We therefore summarise evidence of female-specific harms arising from inhalant misuse.

METHODS

We synthesised pre-clinical and clinical studies of inhalant misuse which were conducted in females, or where sex-differences were reported, into a narrative literature review.

RESULTS

Females experience growth impairments and metabolic dysfunction arising from inhalant misuse, but data on sex-differences are inconclusive. Inhalant misuse in early adolescence may impact menarche and subsequent reproductive capacity, but studies have predominantly focused on the effects of inhalants on offspring rather than on the exposed female. There is limited evidence of sex-differences in relation to cognitive outcomes following exposure to inhalants in pre-clinical models. Females are at an increased risk of psychological harms associated with inhalant misuse, particularly depression and suicidal behaviour.

CONCLUSIONS

The type and magnitude of harms associated with inhalant misuse are sex-specific, but data are limited. We recommend that both pre-clinical and clinical studies of inhalant misuse include both males and females, and should specifically test for and report sex-differences. This can be used to build an evidence base for screening and interventions tailored to females.

[18F]MPPF and [18F]FDG μPET imaging in rats: impact of transport and restraint stress

Background

Stress exposure can significantly affect serotonergic signaling with a particular impact on 5-HT_1A receptor expression. Positron emission tomography (PET) provides opportunities for molecular imaging of alterations in 5-HT_1A receptor binding following stress exposure. Considering the possible role of 5-HT_1A receptors in stress coping mechanisms, respective imaging approaches are of particular interest.

Material and methods

For twelve consecutive days, Sprague Dawley rats were exposed to daily transport with a 1 h stay in a laboratory or daily transport plus 1 h restraint in a narrow tube. Following, animals were subjected to μPET imaging with 2′-methoxyphenyl-(N-2′-pyridinyl)-p-[¹⁸F]fluoro-benzamidoethylpiperazine ([¹⁸F]MPPF) and 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG). Behavioral and biochemical parameters were analyzed to obtain additional information.

Results

In rats with repeated transport, hippocampal [¹⁸F]MPPF binding exceeded that in the naive group, while no difference in [¹⁸F]FDG uptake was detected between the groups. A transient decline in body weight was observed in rats with transport or combined transport and restraint. Thereby, body weight development correlated with [¹⁸F]MPPF binding.

Conclusions

Mild-to-moderate stress associated with daily transport and exposure to a laboratory environment can trigger significant alterations in hippocampal binding of the 5-HT_1A receptor ligand [¹⁸F]MPPF. This finding indicates that utmost care is necessary to control and report transport and associated handling procedures for animals used in μPET studies analyzing the serotonergic system in order to enhance the robustness of conclusions and allow replicability of findings. In view of earlier studies indicating that an increase in hippocampal 5-HT_1A receptor expression may be associated with a resilience to stress, it would be of interest to further evaluate 5-HT_1A receptor imaging approaches as a candidate biomarker for the vulnerability to stress.

The Involvement of Hypothalamus-Pituitary-Adrenal (HPA) Axis in Suicide Risk

Stress and Hypothalamic–Pituitary–Adrenal (HPA) axis dysregulation play a major role in various pathophysiological processes associated with both mood disorders and suicidal behavior. We conducted a systematic review with the primary aim of clarifying the nature and extent of HPA axis activity and suicidal behavior. The second aim of this review was to investigate whether potential biomarkers related to HPA axis abnormalities act as individual susceptibility factors for suicide. The PRISMA statement for reporting systematic reviews was used. Only articles published in English peer-reviewed journals were considered for possible inclusion; we excluded case reports, meta-analyses, and systematic reviews, and studies that did not clearly report statistical analysis, diagnostic criteria, or the number of patients included. Overall, 36 articles on HPA axis and suicide risk met inclusion criteria and were reviewed. Studies that investigated tests detecting biomarkers and the role of early life stressors in suicide risk were also included. We found that HPA axis activity is involved in suicide risk, regardless of the presence or absence of psychiatric conditions. The HPA axis abnormalities, mainly characterized by hyperactivity of the HPA axis, may exert an important modulatory influence on suicide risk. Impaired stress response mechanisms contribute to suicide risk. Targeting HPA axis dysregulation might represent a fruitful strategy for identifying new treatment targets and improving suicide risk prediction.

From Child Abuse to Developing Borderline Personality Disorder Into Adulthood: Exploring the Neuromorphological and Epigenetic Pathway

Borderline personality disorder (BPD) is one of the most common personality disorders seen in the general population. Among multiple identified risk factors, one of the most influential elements is exposure to an adverse childhood experience in terms of emotional, physical, or sexual abuse. A cascade of neuromorphological and epigenetic changes occurs in response to these childhood stressors, which may have a strong link to the development of BPD. PubMed and Google Scholar were searched for articles relevant to child abuse and the development of BPD. The search was not restricted to any time frame or geographic location. Significant epigenetic and neuromorphological changes are seen with child abuse, contributing to the development of BPD. Chronic stressors lead to hypothalamic-pituitary axis (HPA) activation, releasing cortisol that acts on the prefrontal cortex, amygdala, and hippocampus, producing the behavioral patterns seen in BPD. Overstimulation of gray matter leads to permanent neuromorphological changes, which can be visualized in functional MRI/brain scans. Hypermethylation of messenger ribonucleic acid in various sites suggests the impact of child abuse on the genetic level. Interestingly, the prevalence of BPD is seen equally in both genders but is diagnosed more frequently in females because they tend to be more likely to seek help. Understanding the impact of early age life stressors into adulthood calls for serious focus on early diagnosis and intervention. This implies the need for more studies in patients with BPD with or without any childhood traumatic experience and a better understanding of the changes that occur biopsychologically and genetically in response to trauma.

Prevalence of Misophonia and Correlates of Its Symptoms among Inpatients with Depression

Misophonia is an underexplored condition that significantly decreases the quality of life of those who suffer from it. It has neurological and physiological correlates and is associated with a variety of psychiatric symptoms; however, a growing body of data suggests that it is a discrete disorder. While comorbid diagnoses among people with misophonia have been a matter of research interest for many years there is no data on the frequency of misophonia among people with psychiatric disorders. This could be the next step to reveal additional mechanisms underlying misophonia. Until recently, the use of a variety of non-validated questionnaires and the dominance of internet-based studies have been also a major obstacles to a proper definition of misophonia. A total of 94 inpatients diagnosed with depression were assessed for misophonia with face-to-face interviews as well as with MisoQuest-a validated misophonia questionnaire. The prevalence of misophonia among these patients and the congruence of MisoQuest with face-to-face interviews were evaluated. Additionally, the patients filled in a series of questionnaires that measured a variety of psychiatric symptoms and psychological traits. Anxiety, depression, impulsivity, somatic pain, vegetative symptoms, post-traumatic stress disorder (PTSD) symptoms, gender, and age were analyzed in relation to the severity of symptoms of misophonia. Between 8.5 to 12.76% of inpatients with depression were diagnosed with misophonia (depending on measurement and inclusion criteria). MisoQuest accuracy was equal to 92.55%, sensitivity-66.67% and specificity-96.34%. Severity of misophonia symptoms was positively correlated to the greatest extent with anxiety. Moderate positive correlation was also found between severity of misophonia symptoms and depressive symptoms, intrusions, and somatic pain; a weak positive correlation was found between severity of misophonia and non-planning impulsivity, motor impulsivity, avoidance, and vegetative symptoms. There was no relationship between the severity of misophonia symptoms and attentional impulsivity or the age of participants.

Association between suicide risk severity and sarcopenia in non-elderly Chinese inpatients with major depressive disorder

BACKGROUND

Sarcopenia is a skeletal muscle disorder. Recent studies have shown an association between muscle health and suicide. However, there have been no previous studies on the relationship between suicide risk severity and sarcopenia in major depressive disorder (MDD). This study aimed to explore the association between suicide risk severity and sarcopenia in non-elderly Chinese inpatients with MDD.

METHODS

The first-episode drug-naïve MDD inpatients aged 20-59 years with the 24-item Hamilton Rating Scale for Depression (HAMD-24) scores of >20 were included, who were then classified into low, intermediate, high and very high suicide risk groups according to the Nurses' Global Assessment of Suicide Risk (NGASR). The HAMD-24, the Hamilton Rating Scale for Anxiety (HAMA) and the SARC-F questionnaire were used to assess depression severity, anxiety severity and sarcopenia, respectively. The plasma levels of cortisol and adrenocorticotropic hormone (ACTH) were measured.

RESULTS

A total of 192 MDD inpatients (122 females, 70 males; aged 39.3 ± 11.7 years) were included, with 12.5% meeting criteria for sarcopenia. There were significant differences in gender, HAMD score and prevalence of sarcopenia among the suicide risk groups. Adjusted ordinal regression analysis showed that sarcopenia was significantly associated with more severe suicide risk (OR = 2.39, 95%CI 1.02-5.58, p = 0.044) independent of depression severity.

CONCLUSIONS

This study revealed that sarcopenia was significantly associated with higher suicide risk in non-elderly Chinese MDD inpatients after adjustment for depression severity. Intervention of sarcopenia might be effective in reducing the risk of suicide in non-elderly MDD patients.

Incidence of and sociological risk factors for suicide death in patients with leukemia: A population-based study

OBJECTIVES

Suicide is closely related to sociological factors, but sociological analyses of suicide risk in leukemia are lacking. This study is the first to use the Surveillance, Epidemiology, and End Results Program (SEER) database to analyze sociological risk factors for suicide death in leukemia patients.

METHODS

A retrospective search of the SEER database was conducted. Logistic regression was used to identify independent risk factors for suicide death. Variables significant in the univariate logistic regression models were subsequently analyzed using multivariate regression.

RESULTS

The death rate was highest in California (1.73%). Suicide mortality was more common during the 1970s and 1980s, after which it trended downward. Young age at diagnosis (18-34 vs. >64 years: odds ratio [OR] = 1.537, 95% confidence interval [CI] = 1.007-2.347; 35-64 vs. >64 years: OR = 1.610, 95% CI = 1.309-1.979), being male (OR = 1.518, 95% CI = 1.230-1.873), and living where a high proportion of people have at least a bachelor's degree (>50% vs. <20%: OR = 8.115, 95% CI = 5.053-13.034) significantly increased suicide death risk.

CONCLUSION

Our findings could increase clinician awareness of and appropriate support for leukemia patients at risk of death by suicide.

Understanding the Complex of Suicide in Depression: from Research to Clinics

OBJECTIVE

Amongst psychiatric disorders, major depressive disorder (MDD) is the most prevalent, by affecting approximately 15-17% of the population and showing a high suicide risk rate equivalent to around 15%. The present comprehensive overview aims at evaluating main research studies in the field of MDD at suicide risk, by proposing as well as a schematic suicide risk stratification and useful flow-chart for planning suicide preventive and therapeutic interventions for clinicians.

METHODS

A broad and comprehensive overview has been here conducted by using PubMed/Medline, combining the search strategy of free text terms and exploded MESH headings for the topics of 'Major Depressive Disorder' and 'Suicide' as following: ((suicide [Title/Abstract]) AND (major depressive disorder [Title/Abstract])). All articles published in English through May 31, 2019 were summarized in a comprehensive way.

RESULTS

Despite possible pathophysiological factors which may explain the complexity of suicide in MDD, scientific evidence supposed the synergic role of genetics, exogenous and endogenous stressors (i.e., interpersonal, professional, financial, as well as psychiatric disorders), epigenetic, the hypothalamic-pituitary-adrenal stress-response system, the involvement of the monoaminergic neurotransmitter systems, particularly the serotonergic ones, the lipid profile, neuro-immunological biomarkers, the Brain-derived neurotrophic factor and other neuromodulators.

CONCLUSION

The present overview reported that suicide is a highly complex and multifaceted phenomenon in which a large plethora of mechanisms could be variable implicated, particularly amongst MDD subjects. Beyond these consideration, modern psychiatry needs a better interpretation of suicide risk with a more careful assessment of suicide risk stratification and planning of clinical and treatment interventions.

Stress, cortisol and suicide risk

Suicide is a global health issue accounting for at least 800,000 deaths per annum. Numerous models have been proposed that differ in their emphasis on the role of psychological, social, psychiatric and neurobiological factors in explaining suicide risk. Central to many models is a stress-diathesis component which states that suicidal behavior is the result of an interaction between acutely stressful events and a susceptibility to suicidal behavior (a diathesis). This article presents an overview of studies that demonstrate that stress and dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, are important additional risk factors for suicide. Evidence for other putative stress-related suicide risk factors including childhood trauma, impaired executive function, impulsivity and disrupted sleep are considered together with the impact of family history of suicide, perinatal and epigenetic influences on suicide risk.

Suicide in DSM-5: Current Evidence for the Proposed Suicide Behavior Disorder and Other Possible Improvements

Suicide continues to be one of the greatest challenges faced by mental health clinicians and researchers, an issue made worse by increasing trends in the global suicide rate. Suicide behavior disorder (SBD) was introduced in DSM-5 as a disorder for further consideration and potential acceptance into the diagnostic system. There are numerous positive developments that would arise from the addition of a suicide-related diagnosis. Utilizing the 2009 guidelines established by Kendler and colleagues, the present review examines the evidence for SBD's validity and discusses the diagnosis' potential clinical benefits and limitations. Altogether, growing evidence indicates that SBD has preliminary validity and benefit. SBD presents with several significant limitations, however, and possible alternative additions to future DSMs are highlighted.

Zebrafish Mutants Carrying Leptin a (lepa) Gene Deficiency Display Obesity, Anxiety, Less Aggression and Fear, and Circadian Rhythm and Color Preference Dysregulation

Leptin, a hormone secreted by peripheral adipose tissues, regulates the appetite in animals. Recently, evidence has shown that leptin also plays roles in behavioral response in addition to controlling appetite. In this study, we examined the potential function of leptin on non-appetite behaviors in zebrafish model. By using genome editing tool of Transcription activator-like effector nuclease (TALEN), we successfully knocked out leptin a (lepa) gene by deleting 4 bp within coding region to create a premature-translation stop. Morphological and appetite analysis showed the lepa KO fish display a phenotype with obese, good appetite and elevation of Agouti-related peptide (AgRP) and Ghrelin hormones, consistent with the canonical function of leptin in controlling food intake. By multiple behavior endpoint analyses, including novel tank, mirror biting, predator avoidance, social interaction, shoaling, circadian rhythm, and color preference assay, we found the lepa KO fish display an anxiogenic phenotype showing hyperactivity with rapid swimming, less freezing time, less fear to predator, loose shoaling area forming, and circadian rhythm and color preference dysregulations. Using biochemical assays, melatonin, norepinephrine, acetylcholine and serotonin levels in the brain were found to be significantly reduced in lepa KO fish, while the levels of dopamine, glycine and cortisol in the brain were significantly elevated. In addition, the brain ROS level was elevated, and the anti-oxidative enzyme catalase level was reduced. Taken together, by performing loss-of-function multiple behavior endpoint testing and biochemical analysis, we provide strong evidence for a critical role of lepa gene in modulating anxiety, aggression, fear, and circadian rhythm behaviors in zebrafish for the first time.

Cocaine- and Amphetamine-Regulated Transcript (CART) Peptide Plays Critical Role in Psychostimulant-Induced Depression

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter expressed in the central nervous systems. Previously, several reports demonstrated that nucleus accumbal-injected CART peptide positively modulated behavioral sensitization induced by psychostimulants and regulated the mesocorticolimbic dopaminergic pathway. It is confirmed that CART peptide exerted inhibitory effect on psychostimulant-enhanced dopamine receptors signaling, Ca²⁺/calmodulin-dependent kinase signaling and crucial transcription factors expression. Besides modulation of dopamine receptors-related pathways, CART peptide also exhibited elaborated interactions with other neurotransmitter receptors, such as glutamate receptors and γ-aminobutyric acid receptors, which further account for attribution of CART peptide to inhibition of psychostimulant-potentiated locomotor activity. Recently, CART peptide has been shown to have anxiolytic functions on the aversive mood and uncontrolled drug-seeking behaviors following drug withdrawal. Moreover, microinjection of CART peptide has been shown to have an anti-depressant effect, which suggests its potential utility in the mood regulation and avoidance of depression-like behaviors. In this review, we discuss CART pathways in neural circuits and their interactions with neurotransmitters associated with psychostimulant-induced depression.

May nesfatin-1 be a state marker in major depressive disorder with suicidal ideation?

The best known effects of nesfatin-1 are on appetite and metabolic regulation. Moreover, several research suggest that nesfatin-1 play a role in stress responses. This molecule may be involved in the pathophysiology of mood disorders and suicidal behavior. We compared nesfatin-1 levels between depressed patients with suicidal ideation (n = 32, mean ± SD, 1,40 ± 0.11), without suicidal ideation(n = 31, 1.46 ± 0.14) and healthy controls (n = 32, 1.52 ± 0.13). Suicidal ideation was assessed with the Suicide Probability Scale, Scale for Suicide Ideation and depressive symptoms were evaluated with the Hamilton Depression Rating Scale. Blood samples were collected to measure serum nesfatin-1levels by using ELISA method. The study revealed that serum nesfatin-1 levels were significantly lower in MDD with suicidal ideation than in healthy volunteers (p < 0.001). There were a negative correlation between the scores of suicidal ideation and nesfatin-1 levels in MDD with SI group (r = -0.215; p = 0.016). In the future, nesfatin-1 levels may one day be applied in predicting and monitoring patients' suicide risk. Further prospective studies are required to elucidate this potential association.

5-HT1A receptor-mediated activation of neuroendocrine responses and multiple protein kinase pathways in the peripubertal rat hypothalamus

Increasing evidence suggests that multiple factors can produce effects on the immature brain that are distinct and more long-lasting than those produced in adults. The hypothalamic paraventricular nucleus (PVN) is a region integral to the hypothalamic-pituitary-adrenal axis and is affected by anxiety, depression, and drugs used to treat these disorders, yet receptor signaling mechanisms operative in hypothalamus prior to maturation remain to be elucidated. In peripubertal male rats, systemic injection of the selective serotonin 1A (5-HT_1A) receptor agonist (+)8-OH-DPAT (0.2 mg/kg) markedly elevated plasma levels of oxytocin and adrenocorticotropic hormone (ACTH) at 5 and 15 min post-injection. The 5-HT_1A receptor selectivity was demonstrated by the ability of the 5-HT_1A receptor selective antagonist WAY100635 to completely block both oxytocin and ACTH responses at 5 min, with some recovery of the ACTH response at 15 min. At 15 min post-injection, (+)8-OH-DPAT also increased levels of phosphorylated extracellular signal-regulated kinase (pERK) and phosphorylated protein kinase B (pAkt) in the PVN. As previously observed in adults, (+)8-OH-DPAT reduced levels of pERK in hippocampus. WAY100635 also completely blocked (+)8-OH-DPAT-mediated elevations in hypothalamic pERK and pAkt and the reductions in hippocampal pERK, demonstrating 5-HT_1A receptor selectivity of both kinase responses. This study provides the first demonstration of functional 5-HT_1A receptor-mediated ERK and Akt signaling pathways in the immature hypothalamus, activated by a dose of (+)8-OH-DPAT that concomitantly stimulates neuroendocrine responses. This information is fundamental to identifying potential signaling pathways targeted by biased agonists in the development of safe and effective treatment strategies in children and adolescents.

Plasma cortisol and oxytocin levels predict help-seeking intentions for depressive symptoms

BACKGROUND

Depressed individuals often refuse or withdraw from help, a phenomenon termed help-negation, which is a risk factor for poor outcomes. Most previous research has investigated psychosocial factors including stigma as causes of low help-seeking intentions for depression, however these do not adequately explain the problem. We hypothesised that because help-negation worsens with symptom severity, it might be linked to important biological changes associated with depression itself. We investigated the relative contributions of cortisol, a stress hormone linked to depression, and oxytocin, a hormone which mediates social behaviours, alongside psychosocial factors, to help-seeking intentions among depressed and non-depressed individuals.

METHODS

Morning plasma cortisol and oxytocin levels, psychopathology, suicidal ideation, help-seeking intentions from informal sources including family and friends, and formal sources including health professionals, and perceived social support were quantified in 63 adults meeting DSM-5 criteria for major depressive disorder (MDD) who were not receiving any treatment, and 60 healthy controls. Between-group analyses of variance, correlations, and hierarchical multiple regressions were employed.

RESULTS

Help-seeking intentions were lower in depressed than healthy participants, negatively correlated to cortisol and positively correlated to oxytocin. Cortisol negatively, and oxytocin positively, predicted help-seeking intentions from informal but not formal sources, after controlling for psychopathology and psychosocial factors.

CONCLUSIONS

Neuroendocrine changes associated with depression may contribute to low help-seeking from friends and family, which may have implications for interpersonal support and outcomes. Research and clinical approaches which incorporate biological as well as psychosocial factors may allow for more targeted and effective early interventions to address lack of help-seeking and depression progression.

Serum cholesterol and Suicide in first episode psychosis: A preliminary study

BACKGROUND

Low levels of cholesterol have been described in suicide behavior including among those individuals who have an increased tendency for impulsivity. Violent suicide attempters show significantly lower cholesterol levels than nonviolent suicide attempters. The suicide rate is particularly high in the prodromal and early phase of schizophrenia. It is unclear if there is a psychopathological relationship between early psychosis, suicide, and cholesterol levels. The present study examines levels of cholesterol and suicide behavior in a cohort of early psychosis.

METHODOLOGY

Sixty admitted patients with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis of nonaffective schizophrenia spectrum disorder (early psychosis) were assessed in a naturalistic cross-sectional, cohort study. Psychopathology was assessed with the Positive and Negative Symptom Scale for Schizophrenia (PANSS), Hamilton Depression Rating Scale, and Scale for Impact of Suicidality-Management, Assessment and Planning of Care (SIS-MAP). Serum levels of cholesterol were estimated in the cohort as well. The findings were analyzed for a clinical correlation of cholesterol levels, suicidal attempters, and psychopathology.

RESULTS

Out of 60 patients, 13 patients had a suicide attempt in the recent past. No serum cholesterol abnormality (3.7 ± 1.2 mmol/L) was observed in patients as a group and those with low suicidality (SIS-MAP <17, serum cholesterol: 4.1 ± 1.3 mmol/L). However, low levels of cholesterol were observed in a subgroup with severe suicidality (SIS-MAP >33; serum cholesterol: 3.5 ± 1.4 mmol/L). Females with moderate suicidality showed statistically significant lower cholesterol levels than males (P = 0.047).

CONCLUSIONS

The study suggests lower levels of cholesterol in patients of psychosis with severe suicidal thoughts and depression in early psychosis. More research is required in this field to determine the neurochemistry of suicide behavior in psychosis and its significance in the prediction of suicidal behavior.

Stress hormones at rest and following exercise testing predict coronary artery disease severity and outcome

OBJECTIVES

Despite considerable knowledge regarding the importance of stress in coronary artery disease (CAD) pathogenesis, its underestimation persists in routine clinical practice, in part attributable to lack of a standardized, objective assessment. The current study examined the ability of stress hormones to predict CAD severity and prognosis at basal conditions as well as during and following an exertional stimulus.

MATERIALS AND METHODS

Forty Caucasian subjects with significant coronary artery lesions (≥50%) were included. Within 2 months of coronary angiography, cardiopulmonary exercise testing (CPET) on a recumbent ergometer was performed in conjunction with stress echocardiography (SE). At rest, peak and after 3 min of recovery following CPET, plasma levels of cortisol, adrenocorticotropic hormone (ACTH) and NT-pro-brain natriuretic peptide (NT-pro-BNP) were measured by immunoassay sandwich technique, radioimmunoassay, and radioimmunometric technique, respectively. Subjects were subsequently followed a mean of 32 ± 10 months.

RESULTS AND DISCUSSION

Mean ejection fraction was 56.7 ± 9.6%. Subjects with 1-2 stenotic coronary arteries (SCA) demonstrated a significantly lower plasma cortisol levels during CPET compared to those with 3-SCA (p < .05), whereas ACTH and NT-pro-BNP were not significantly different (p > .05). Among CPET, SE, and hormonal parameters, cortisol at rest and during CPET recovery demonstrated the best predictive value in distinguishing between 1-, 2-, and 3-SCA [area under ROC curve 0.75 and 0.77 (SE = 0.11, 0.10; p = .043, .04) for rest and recovery, respectively]. ΔCortisol peak/rest predicted cumulative cardiac events (area under ROC curve 0.75, SE = 0.10, p = .049).

CONCLUSIONS

Cortisol at rest and following an exercise test holds predictive value for CAD severity and prognosis, further demonstrating a link between stress and unwanted cardiac events.

Borderline personality disorder and childhood trauma: exploring the affected biological systems and mechanisms

BACKGROUND

According to several studies, the onset of the Borderline Personality Disorder (BPD) depends on the combination between genetic and environmental factors (GxE), in particular between biological vulnerabilities and the exposure to traumatic experiences during childhood. We have searched for studies reporting possible alterations in several biological processes and brain morphological features in relation to childhood trauma experiences and to BPD. We have also looked for epigenetic mechanisms as they could be mediators of the effects of childhood trauma in BPD vulnerability.

DISCUSSION

We prove the role of alterations in Hypothalamic-Pituitary-Adrenal (HPA) axis, in neurotrasmission, in the endogenous opioid system and in neuroplasticity in the childhood trauma-associated vulnerability to develop BPD; we also confirm the presence of morphological changes in several BPD brain areas and in particular in those involved in stress response. Not so many studies are available on epigenetic changes in BPD patients, although these mechanisms are widely investigated in relation to stress-related disorders. A better comprehension of the biological and epigenetic mechanisms, affected by childhood trauma and altered in BPD patients, could allow to identify "at high risk" subjects and to prevent or minimize the development of the disease later in life.

Non-violent and violent forms of childhood abuse in the prediction of suicide attempts: Direct or indirect effects through psychiatric disorders?

BACKGROUND

Childhood abuse is linked to suicide. Potential pathways include the increased risk for the development of psychiatric disorders and the contribution of abuse to suicide capability. The current study compared the effects of childhood non-violent and violent abuse in the prediction of suicide attempts, and examined the potential mediated effects of psychiatric disorders.

METHODS

Data from the National Comorbidity Surveys were obtained. At baseline, assessments of childhood non-violent abuse (e.g., parental verbal abuse) and violent abuse (e.g., parental physical abuse, relative rape) were obtained. We also assessed for other adverse childhood experiences, baseline suicidal behaviors, and psychiatric disorders. At the ten-year follow-up, we assessed for psychiatric disorders and suicide attempts that had occurred over time.

RESULTS

Both non-violent and violent abuse predicted attempts, though participants experiencing violent abuse had significantly higher rates. Bootstrapped mediation analyses determined that the influence of non-violent abuse on suicide attempts was indirect, and exerted its influence through the psychiatric disorders that occurred during the ten-year follow-up.

LIMITATIONS

The study relied on retrospective reports of childhood abuse. Further, we could not clearly determine the temporal order of the psychiatric disorders and suicide attempts occurring over follow-up.

CONCLUSION

Different mechanisms may underlie the pathway between violent and non-violent abuse and suicide attempts. Verbal abuse may lead to negative cognitive styles and psychiatric disorders associated with suicidality; violent abuse may contribute to the capacity for suicide. Interventions may need to be specifically tailored to meet the distinct needs of individuals who have experienced past childhood abuse.

The Rodent Forced Swim Test Measures Stress-Coping Strategy, Not Depression-like Behavior

The forced swim test (FST) measures coping strategy to an acute inescapable stress and thus provides unique insight into the neural limb of the stress response. Stress, particularly chronic stress, is a contributing factor to depression in humans and depression is associated with altered response to stress. In addition, drugs that are effective antidepressants in humans typically promote active coping strategy in the FST. As a consequence, passive coping in the FST has become loosely equated with depression and is often referred to as "depression-like" behavior. This terminology oversimplifies complex biology and misrepresents both the utility and limitations of the FST. The FST provides little construct- or face-validity to support an interpretation as "depression-like" behavior. While stress coping and the FST are arguably relevant to depression, there are likely many factors that can influence stress coping strategy. Importantly, there are other neuropsychiatric disorders characterized by altered responses to stress and difficulty in adapting to change. One of these is autism spectrum disorder (ASD), and several mouse genetic models of ASD exhibit altered stress-coping strategies in the FST. Here we review evidence that argues a more thoughtful consideration of the FST, and more precise terminology, would benefit the study of stress and disorders characterized by altered response to stress, which include but are not limited to depression.

Menarche, menstrual problems and suicidal behavior in Chinese adolescents

BACKGROUND

Menarche is the first menstrual cycle. Menstrual problems, such as dysmenorrheal menorrhagia, oligomenorrhea, and irregular cycle are common in female adolescents. This research aims to examine the associations between age at menarche and menstrual problems and suicidal behavior among Chinese female adolescents.

METHODS

An epidemiological survey of 5831 female adolescents from eight high schools of three counties of Shandong province, China, was conducted. A self-administered paper-and-pencil questionnaire was used to collect information. Logistic regression analyses were used to examine the association between menstruation and suicidality.

RESULTS

The mean age of the sample was 15.02 (SD=1.44) years. Of the sample, 5,231 (90.0%) had experienced their first menstrual cycle, and 23.2%, 10.4%, and 4.5% of the sample reported having had suicidal ideation, plan and attempt, respectively. In multivariate models, menarche at ≤11 years was associated with increased risk of suicidal ideation (OR=1.41, 95%CI: 1.10-1.81) and menarche at 12 years was associated with suicide plan (OR=1.23, 95%CI: 1.00-1.51). Irregular menstrual cycle was significantly associated with increased risk of suicidal ideation (OR=1.40, 95%CI: 1.05-1.86) and menstrual period less than or equal to 4 days was significantly associated with increased risk of suicide plan (OR=1.32, 95%CI: 1.06-1.66).

LIMITATIONS

This cross-sectional study cannot establish the causal directions between menstrual problems and suicidality in adolescents.

CONCLUSIONS

Our study suggests that earlier menarche, irregular menstrual cycle and short menstrual period are associated with suicidal behavior in female adolescents. Further research is warranted to examine the causal relationship between menstrual problems and suicidal behavior in adolescents.

Suicide in patients with genitourinary malignancies

Genitourinary cancers are significant causes of morbidity and mortality around the world. The present review summarises the current literature on suicide and its risk factors among patients with genitourinary cancers. The review was based on relevant articles published in MEDLINE, ProQuest, PsycINFO, Science Direct and Scopus databases. Patients with prostate cancer represented the most important risk group for suicide, among patients with urogenital cancers. Other risk factors are male gender, older age, white race, advanced disease, living alone and co-existing psychological comorbidities. Findings from the review call for a greater caregiver awareness on psychosocial morbidity and suicidality among genitourinary cancer patients pre- and post-treatment and their early identification, adoption of risk-reduction strategies and prompt referral for expert mental health care.