Neuroinflammation and depressive disorder: The role of the hypothalamus

Dysregulation of immune system markers, gut microbiota and short-chain fatty acid production following prenatal alcohol exposure: A developmental perspective

Prenatal alcohol exposure (PAE) can severely impact fetal development, including alterations to the developing immune system. Immune perturbations, in tandem with gut dysbiosis, have been linked to brain and behavioral dysfunction, but this relationship is poorly understood in the context of PAE. This study takes an ontogenetic approach to evaluate PAE-induced alterations to brain and serum cytokine levels and both the composition and metabolic output of the gut microbiota. Using a well-established rat model of PAE, cytokine levels in the serum, prefrontal cortex, amygdala, and hypothalamus as well as gut microbiota composition and short-chain fatty acid (SCFA) levels were assessed at three postnatal (P) timepoints: P8 (infancy), P22 (weaning), and P38 (adolescence). Male PAE rats had increased cytokine levels in the amygdala and hypothalamus, but not prefrontal cortex, at P8. This altered neuroimmune function was not seen in the PAE females. The effect of PAE on central cytokine levels was reduced at P22/38, the same age at which PAE-induced alterations in serum cytokine levels emerge in both sexes. PAE reduced bacterial diversity in both sexes at P8, but only in females at P38, where a PAE-induced unique community composition emerged. Both sexes had alterations to specific bacterial taxa (e.g., Firmicutes), some of which are important in producing the SCFA butyric acid, which was decreased in PAE animals at P22. These results demonstrate that PAE leads to sex- and age-specific alterations in immune function, gut microbiota and SCFA production, highlighting the need to consider both age and sex in future work.

Associations between hypothalamic-pituitary-adrenal (HPA) axis hormone levels, major depression features and antidepressant effects of ketamine

BACKGROUND

Subanesthetic doses of (R,S)-ketamine (ketamine) have demonstrated rapid and robust antidepressant effects in individuals with depression. However, individual variability in response to ketamine exists, and current biomarkers of ketamine treatment response are not entirely understood. Preclinical evidence suggests a link between hypothalamic-pituitary-adrenal (HPA) axis activation, a determinant of the stress response system, and ketamine's efficacy in stressed mice exhibiting enhanced antidepressant responses. Here, we assessed the relationship between HPA axis, major depression features, and antidepressant response to ketamine in humans.

METHODS

We investigated 42 participants following medication washout with treatment-resistant depression who participated in a randomized, placebo-controlled, crossover trial receiving intravenous ketamine. Plasma levels of corticotropin-releasing factor (CRF), adrenocorticotropic hormone (ACTH), and cortisol were measured at baseline. Ketamine's antidepressant effects were assessed using the Montgomery-Asberg Depression Rating Scale.

RESULTS

We found that baseline HPA axis hormone levels did not significantly moderate the antidepressant effects of ketamine. However, a negative association was observed between ACTH and CRF levels and the overall duration of depressive episodes, suggesting potential biomarker implications. Also, a negative correlation between baseline depressive scores and age of onset was observed, suggesting that the severity of depression might be greater if it develops at a younger age, indicating more enduring stress on the brain and body.

DISCUSSION

Although we did not find a moderation effect of the plasma HPA axis hormones on the antidepressant effects of ketamine, moderation effects of the brain HPA axis hormones cannot be precluded and warrants further investigation. Importantly, our results implicate HPA axis components as potential biomarkers for the duration of depressive episodes.

Emotional and behavioral problems accelerate hypothalamic development from childhood to adolescence: Findings from a longitudinal cohort study

BACKGROUND

Despite the pivotal role of the hypothalamus in regulating various physiological processes, our understanding of its developmental trajectory and subregional organization during childhood and adolescence remains limited, as well as how emotional and behavioral problems can impact hypothalamic development, potentially leading to neurodevelopmental disorders.

METHODS

This population-based longitudinal cohort study utilized data from a representative sample of 702 children, who were followed two to five times. Emotional and behavioral problems were assessed using the Strengths and Difficulties Questionnaire (SDQ). Linear mixed models were employed to delineate developmental trajectories and behavioral regulation.

RESULTS

Using an automated segmentation technique, we quantified the volumes and asymmetries of the hypothalamus and its subregions in a large longitudinal sample of 702 subjects aged 6-15 years with 1371 MRI scans, and mapped their developmental trajectories. Our findings indicate that while the anterior and posterior regions of the hypothalamus exhibit a tendency toward decline, the tubular region demonstrates a linear increase which is influenced by lateralization, sex, and intracranial volume. Furthermore, emotional and behavioral problems - particularly emotional symptoms and peer relationship problems - accelerate development in superior tubular and anterior-superior regions.

CONCLUSIONS

In this study, we initially delineated the developmental trajectories of the hypothalamus and its subregions from childhood to adolescence based on a longitudinal cohort study. Our findings revealed that the development of hypothalamus followed the pattern of "lateral early to medial late, and dorsomedial early to ventromedial late", and the emotional and behavioral problems accelerate hypothalamic development. This study provides preliminary evidence regarding the impact of emotional and behavioral problems on the dynamic development of the hypothalamus, offering a crucial foundation for future prevention and intervention strategies targeting cognitive and emotional behavioral problems.

Neural circuits mediating chronic stress: Implications for major depressive disorder

Major depressive disorder (MDD), also known as depression, is a prevalent mental disorder that leads to severe disease burden worldwide. Over the past two decades, significant progress has been made in understanding the pathogenesis and developing novel treatments for MDD. Among the complicated etiologies of MDD, chronic stress is a major risk factor. Exploring the underlying brain circuit mechanisms of chronic stress regulation has been an area of active research for recent years. A growing body of preclinical and clinical research has revealed that abnormalities in the brain circuits are closely associated with failures in coping with stress in depressed individuals. Nevertheless, neural circuit mechanisms underlying chronic stress processing and the onset of depression remain a major puzzle. Here, we review recent literature focusing on circuit- and cell-type-specific dissection of depression-like behaviors in chronic stress-related animal models of MDD and outline the key questions.

Multiple lesion inductions intensify central sensitization driven by neuroinflammation in a mouse model of endometriosis

Introduction

Endometriosis is an inflammatory disease associated with chronic pelvic pain (CPP). Growing evidence indicates that endometriotic lesions are not the sole source of pain. Instead, central nervous system (CNS) dysfunction created by prolonged peripheral and central sensitization plays a role in developing endometriosis-associated CPP. This study investigated how CPP is established using a multiple lesion induction mouse model of endometriosis, as repeated retrograde menstruation is considered underlying endometriosis pathogenesis.

Methods

We generated endometriosis-like lesions by injecting endometrial tissue fragments into the peritoneal cavity in mice. The mice received a single (1x) or multiple inductions (6x) to simulate recurrent retrograde menstruation. Lesion development, hyperalgesia by behavioral testing, signs of peripheral sensitization, chronic inflammation, and neuroinflammation were examined with lesions, peritoneal fluids, dorsal root ganglia (DRG), spinal codes, and brain.

Results

Multiple lesion inductions increased lesion numbers and elevated abdominal and hind paw hypersensitivity compared to single induction mice. Elevated persistent glial cell activation across several brain regions and/or spinal cords was found in the multiple induction mice. Specifically, IBA1+ microglial soma size was increased in the hippocampus and thalamus. IBA1+ cells were abundant in the cortex, hippocampus, thalamus, and hypothalamus of the multiple induction mice. GFAP+ astrocytes were mainly elevated in the hippocampus. Elevated TRPV1, SP, and CGRP expressions in the DRG were persistent in the multiple induction mice. Furthermore, multiple inductions induced the severe disappearance of TIM4hi MHCIIlo residential macrophages and the influx of increased proinflammatory TIM4lo MHCIIhi macrophages in the peritoneal cavity. The single and multiple inductions elevated secreted TNFα, IL-1β, and IL-6 levels in the peritoneal cavity at 2 weeks. Elevated cytokine levels returned to the pre-induction levels in the single induction mice at 6 weeks; however, they remained elevated in the multiple induction mice.

Conclusions

Our results indicate that the repeatedly occurring lesion inductions (=mimic retrograde menstruation) can be a peripheral stimulus that induces nociceptive pain and creates composite chronic inflammatory stimuli to cause neuroinflammation and sensitize the CNS. The circuits of neuroplasticity and stimulation of peripheral organs via a feedback loop of neuroinflammation may mediate widespread endometriosis-associated CPP.

ASSOCIATION BETWEEN ANXIETY AND DEPRESSION IN METABOLIC DYSFUNCTION-ASSOCIATED STEATOTIC LIVER DISEASE (MASLD)

BACKGROUND

This study aimed to assess the frequency and intensity of anxious and depressive symptoms in patients diagnosed with metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

This is a descriptive and cross-sectional study, resulting from 106 patients from the Hepatology outpatient clinic at the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), São Paulo, Brazil without a history of alcohol abuse, verified by the alcohol use disorders identification test (AUDIT). These were assessed using the sociodemographic data sheet, Hospital Anxiety and Depression Scale (HADS), Hamilton Anxiety Rating Scale (HAM-A), and Hamilton Depression Scale (HAM-D).

RESULTS

A total of 69.8% were women and 30.2% were men, with a mean age of 61 years. The majority (71.7%) discovered MASLD through routine exams, presenting as comorbidities: Type 2 diabetes mellitus (59.4%), Dyslipidemia (49.1%), Arterial hypertension (68.9%), Obesity (61.3%) and Metabolic syndrome [MetS (63.2%)]. The HADS scale indicates 34% probability of anxiety and 33% depressive symptoms. The Hamilton's scales of intensity indicates 63.9% severe anxiety and 54.3% severe depression. There is also a relationship between anxiety, depression and the female gender, as well as between depression and MetS.

CONCLUSION

The findings point to the presence of anxiety and depression in more than one third of MASLD patients, most with severe symptoms. The group is concentrated in the elderly, with many comorbidities, including MetS. There was a positive correlation between anxiety, depression and being female; also, being significant between MetS and depression.

Novel Insights into Changes in Gene Expression within the Hypothalamus in Two Asthma Mouse Models: A Transcriptomic Lung-Brain Axis Study

Patients with asthma experience elevated rates of mental illness. However, the molecular links underlying such lung-brain crosstalk remain ambiguous. Hypothalamic dysfunction is observed in many psychiatric disorders, particularly those with an inflammatory component due to many hypothalamic regions being unprotected by the blood-brain barrier. To gain a better insight into such neuropsychiatric sequelae, this study investigated gene expression differences in the hypothalamus following lung inflammation (asthma) induction in mice, using RNA transcriptome profiling. BALB/c mice were challenged with either bacterial lipopolysaccharide (LPS, E. coli) or ovalbumin (OVA) allergens or saline control (n = 7 per group), and lung inflammation was confirmed via histological examination of postmortem lung tissue. The majority of the hypothalamus was micro-dissected, and total RNA was extracted for sequencing. Differential expression analysis identified 31 statistically significant single genes (false discovery rate FDR5%) altered in expression following LPS exposure compared to controls; however, none were significantly changed following OVA treatment, suggesting a milder hypothalamic response. When gene sets were examined, 48 were upregulated and 8 were downregulated in both asthma groups relative to controls. REACTOME enrichment analysis suggests these gene sets are involved in signal transduction metabolism, immune response and neuroplasticity. Interestingly, we identified five altered gene sets directly associated with neurotransmitter signaling. Intriguingly, many of these altered gene sets can influence mental health and or/neuroinflammation in humans. These findings help characterize the links between asthma-induced lung inflammation and the brain and may assist in identifying relevant pathways and therapeutic targets for future intervention.

Resocialization mitigates depressive behaviors induced by social isolation stress in mice: Attenuation of hippocampal neuroinflammation and nitrite level

BACKGROUND AND AIM

Social isolation stress (SIS) is a stressor known to trigger depressive behaviors. Psychiatric disorders are associated with neurobiological changes, such as neuroinflammation and an increase in nitric oxide (NO) signaling. Despite the well-established detrimental effects of SIS and the involvement of neuroinflammation and NO in depression, potential management strategies, especially resocialization, remain insufficiently explored. Our aim was to elucidate the effects of resocialization on depressive behaviors in socially isolated mice, with a focus on the possible involvement of neuroinflammation and nitrite in the hippocampus (HIP).

METHODS

We utilized 24 Naval Medical Research Institute male mice, maintained under both social and isolation conditions (SC and IC). After the isolation period, the mice were divided into two groups of eight, including the SIS group and a resocialized group. The SC group was kept without exposure to isolation stress. We conducted the open-field test, forced swimming test, and splash test to evaluate depressive behaviors. Additionally, nitrite levels, as well as the gene expression of interleukin (IL)-1β, tumor necrosis factor (TNF), and toll-like receptor 4 (TLR4) in the HIP, were measured.

RESULTS

The study found that resocialization significantly reduces depressive behaviors in SIS mice. The results suggest that the antidepressive effects of resocialization may be partially due to the modulation of the neuroinflammatory response and nitrite levels in the HIP. This is supported by the observed decrease in hippocampal gene expression of IL-1β, TLR4, and TNF, along with a reduction in nitrite levels following resocialization.

CONCLUSION

These insights could pave the way for new management strategies for depression, emphasizing the potential benefits of social interactions.

Chronic Stress-Induced Neuroinflammation: Relevance of Rodent Models to Human Disease

The brain is the central organ of adaptation to stress because it perceives and determines threats that induce behavioral, physiological, and molecular responses. In humans, chronic stress manifests as an enduring consistent feeling of pressure and being overwhelmed for an extended duration. This can result in a persistent proinflammatory response in the peripheral and central nervous system (CNS), resulting in cellular, physiological, and behavioral effects. Compounding stressors may increase the risk of chronic-stress-induced inflammation, which can yield serious health consequences, including mental health disorders. This review summarizes the current knowledge surrounding the neuroinflammatory response in rodent models of chronic stress-a relationship that is continually being defined. Many studies investigating the effects of chronic stress on neuroinflammation in rodent models have identified significant changes in inflammatory modulators, including nuclear factor-κB (NF-κB) and toll-like receptors (TLRs), and cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-6. This suggests that these are key inflammatory factors in the chronic stress response, which may contribute to the establishment of anxiety and depression-like symptoms. The behavioral and neurological effects of modulating inflammatory factors through gene knockdown (KD) and knockout (KO), and conventional and alternative medicine approaches, are discussed.

The kynurenine and serotonin pathway, neopterin and biopterin in depressed children and adolescents: an impact of omega-3 fatty acids, and association with markers related to depressive disorder. A randomized, blinded, prospective study

Depressive disorder is a severe mental condition. In addition to genetic factors, immunological-inflammatory factors, oxidative stress, and disturbances in neurotransmitter metabolism, kynurenine and serotonin pathways may play a role. The exact mechanisms, especially in depressed children and adolescents, are not fully understood. Our primary hypothesis was whether the metabolites of tryptophan degradation in children and adolescents with depressive disorder might be influenced by omega-3 FAs compared to omega-6 FAs during a 12-week supplementation. A secondary hypothesis was to investigate whether tryptophan metabolites in children and adolescents are associated with markers of inflammatory response, oxidative stress, cortisol, and the serum omega-6/omega-3 FA ratio. Metabolites of tryptophan degradation and pteridines, neopterin, and biopterin in urine were analyzed with an HPLC system. Surprisingly, omega-3 FAs stimulated both kynurenine (kynurenine/tryptophan ratio) and serotonin (5-hydroxytryptophan) pathways, whereas omega-6 FAs only increased the kynurenine/tryptophan ratio. Neopterin and biopterin were not different from the healthy controls. Biopterin increased after omega-3 FA supplementation. Serotonin was positively correlated with lipoperoxidation and a marker of oxidative protein damage. Of the monitored tryptophan metabolites, only 5-hydroxyindolacetic acid was positively correlated with the severity of depression, total cholesterol, and negatively with brain-derived neurotrophic factor and glutathione peroxidase. In conclusion, in children and adolescents, both supplemented FAs stimulated the kynurenine pathway (kynurenine/tryptophan ratio) and kynurenine formation. However, the serotonin pathway (5-hydroxytryptophan) was stimulated only by omega-3 FA. Tryptophan metabolism is associated with oxidative stress, inflammation, total cholesterol, and cortisol. We are the first to point out the association between the kynurenine pathway (KYN/TRP ratio) and the omega-6/omega-3 FA ratio. The metabolite 5-HIAA could play a role in the pathophysiology of depressive disorder in children and adolescents.

Clinical Trial Registration

https://www.isrctn.com/ISRCTN81655012, identifier ISRCTN81655012.

New Insights into the Mutual Promotion of Rosacea, Anxiety, and Depression from Neuroendocrine Immune Aspects

Rosacea is a common chronic inflammatory skin disease with a complex etiology and undefined pathogenesis, and there is still a lack of targeted clinical treatment. Patients with rosacea are at a higher risk of anxiety and depression compared to the healthy population. Compared to skin conditions such as acne and psoriasis, rosacea has been much less studied in relation to multiple-etiology psychiatric disorders such as anxiety and depression. In contrast to the mainstream belief that the causal association between rosacea and psychiatric disorders is that rosacea increases the psychological burden of patients and thus triggers psychiatric disorders simply by altering their facial appearance, this review outlines the possible common mechanisms between rosacea and anxiety and depression disorders, starting from the pathophysiological mechanisms of transient receptor potential family cation channels, HPA axis, and Th1/Th17 cell polarization. It envisages the possibility of the neuroendocrine-immune interplay between rosacea and anxiety and depression, and new ideas on the complex causal relationship between rosacea and psychiatric disorders, offering more orientations to open up new therapeutic approaches for rosacea.

The Melanocortin System: A Promising Target for the Development of New Antidepressant Drugs

Major depression is one of the most prevalent mental disorders, causing significant human suffering and socioeconomic loss. Since conventional antidepressants are not sufficiently effective, there is an urgent need to develop new antidepressant medications. Despite marked advances in the neurobiology of depression, the etiology and pathophysiology of this disease remain poorly understood. Classical and newer hypotheses of depression suggest that an imbalance of brain monoamines, dysregulation of the hypothalamic-pituitary-adrenal axis (HPAA) and immune system, or impaired hippocampal neurogenesis and neurotrophic factors pathways are cause of depression. It is assumed that conventional antidepressants improve these closely related disturbances. The purpose of this review was to discuss the possibility of affecting these disturbances by targeting the melanocortin system, which includes adrenocorticotropic hormone-activated receptors and their peptide ligands (melanocortins). The melanocortin system is involved in the regulation of various processes in the brain and periphery. Melanocortins, including peripherally administered non-corticotropic agonists, regulate HPAA activity, exhibit anti-inflammatory effects, stimulate the levels of neurotrophic factors, and enhance hippocampal neurogenesis and neurotransmission. Therefore, endogenous melanocortins and their analogs are able to complexly affect the functioning of those body’s systems that are closely related to depression and the effects of antidepressants, thereby demonstrating a promising antidepressant potential.

Mood Disorders in Youth: Complementary and Integrative Medicine

Omega-3 polyunsaturated fatty acids, probiotics, vitamin C, vitamin D, folic acid and L-methyl folate, broad-spectrum micronutrients, N-acetylcysteine, physical activity, herbs, bright light therapy, melatonin, saffron, meditation, school-based interventions, and transcranial photobiomodulation are reviewed, with a focus on their use for treating mood disorders in children and adolescents. For each treatment, all published randomized controlled trials are summarized.

α7 Nicotinic acetylcholine receptor: a key receptor in the cholinergic anti-inflammatory pathway exerting an antidepressant effect

Depression is a common mental illness, which is related to monoamine neurotransmitters and the dysfunction of the cholinergic, immune, glutamatergic, and neuroendocrine systems. The hypothesis of monoamine neurotransmitters is one of the commonly recognized pathogenic mechanisms of depression; however, the drugs designed based on this hypothesis have not achieved good clinical results. A recent study demonstrated that depression and inflammation were strongly correlated, and the activation of alpha7 nicotinic acetylcholine receptor (α7 nAChR)-mediated cholinergic anti-inflammatory pathway (CAP) in the cholinergic system exhibited good therapeutic effects against depression. Therefore, anti-inflammation might be a potential direction for the treatment of depression. Moreover, it is also necessary to further reveal the key role of inflammation and α7 nAChR in the pathogenesis of depression. This review focused on the correlations between inflammation and depression as well-discussed the crucial role of α7 nAChR in the CAP.

Endometriosis leads to central nervous system-wide glial activation in a mouse model of endometriosis

BACKGROUND

Chronic pelvic pain (CPP) is a common symptom of endometriosis. Women with endometriosis are also at a high risk of suffering from anxiety, depression, and other psychological disorders. Recent studies indicate that endometriosis can affect the central nervous system (CNS). Changes in the functional activity of neurons, functional magnetic resonance imaging signals, and gene expression have been reported in the brains of rat and mouse models of endometriosis. The majority of the studies thus far have focused on neuronal changes, whereas changes in the glial cells in different brain regions have not been studied.

METHODS

Endometriosis was induced in female mice (45-day-old; n = 6-11/timepoint) by syngeneic transfer of donor uterine tissue into the peritoneal cavity of recipient animals. Brains, spines, and endometriotic lesions were collected for analysis at 4, 8, 16, and 32 days post-induction. Sham surgery mice were used as controls (n = 6/timepoint). The pain was assessed using behavioral tests. Using immunohistochemistry for microglia marker ionized calcium-binding adapter molecule-1 (IBA1) and machine learning "Weka trainable segmentation" plugin in Fiji, we evaluated the morphological changes in microglia in different brain regions. Changes in glial fibrillary acidic protein (GFAP) for astrocytes, tumor necrosis factor (TNF), and interleukin-6 (IL6) were also evaluated.

RESULTS

We observed an increase in microglial soma size in the cortex, hippocampus, thalamus, and hypothalamus of mice with endometriosis compared to sham controls on days 8, 16, and 32. The percentage of IBA1 and GFAP-positive area was increased in the cortex, hippocampus, thalamus, and hypothalamus in mice with endometriosis compared to sham controls on day 16. The number of microglia and astrocytes did not differ between endometriosis and sham control groups. We observed increased TNF and IL6 expression when expression levels from all brain regions were combined. Mice with endometriosis displayed reduced burrowing behavior and hyperalgesia in the abdomen and hind-paw.

CONCLUSION

We believe this is the first report of central nervous system-wide glial activation in a mouse model of endometriosis. These results have significant implications for understanding chronic pain associated with endometriosis and other issues such as anxiety and depression in women with endometriosis.

Electroacupuncture alleviates perioperative hypothalamus-pituitary-adrenal axis dysfunction via circRNA-miRNA-mRNA networks

Electroacupuncture (EA) has long been used to alleviate surgery-induced hypothalamic-pituitary-adrenal axis dysfunction. However, its downstream gene targets in the brain remain unclear. The aim of the present study was to clarify the potential targets of EA based on RNA sequencing techniques (RNA-seq). Rats were divided into normal control (NC), hepatectomy surgery (HT), HT + EA, and HT + sham EA groups followed by RNA-seq of two representative nuclei in the hypothalamus and amygdala. Weighted Gene Co-expression Network Analysis and Gene Set Enrichment Analysis identified six gene modules associated with neuroendocrine transmitters and neural remodeling in the hypothalamus. Furthermore, circRNA-miRNA-mRNA interaction networks revealed EA-related candidate miRNAs and circRNAs, of which opioid receptor mu 1 might be an EA-specific target, and showed regulation by competing endogenous RNA. We identified the neuroendocrine circRNA-miRNA-mRNA networks through which EA has an effect on HPA axis dysfunction, thus providing potential targets and future research directions for EA treatment.

Proinflammatory dietary pattern and depression risk in older adults: Prospective analyses from the Seniors-ENRICA studies

BACKGROUND & AIMS

Only a few studies have assessed the association between a proinflammatory diet and the risk of depression in older adults, and they have rendered weak results. The present study analysed the association between the Dietary Inflammatory Index (DII) and incident self-reported diagnosis or symptoms of depression in two cohorts of community-dwelling older adults in Spain.

METHODS

We used data from the Seniors-ENRICA-I (SE-I) and Seniors-ENRICA-II (SE-II) cohorts. In both cohorts, the baseline DII was calculated from habitual food consumption estimated with a validated computer-based diet history. The incidence of both physician self-reported diagnosis of depression and mild-to-major depressive symptoms (≥3 on the 10-item Geriatric Depression Scale) was analysed. Logistic regression models were adjusted for the main potential confounders, such as sociodemographics, lifestyles, and comorbidities. The results of both cohorts were pooled using a random effects model.

RESULTS

Among the 1627 participants in SE-I (mean age 71.5 ± 5.5 y, 53.1% women) and the 1579 in SE-II (mean age 71.4 ± 4.2, 46.7% women), 86 (5.3%) and 140 (8.9%) incident cases of depression were identified after a mean 3.2-y and 2.3-y follow-up, respectively. The fully adjusted odds ratio (95% confidence interval) of incident depression for the highest (the highest proinflammatory diet) versus the lowest quartile of DII was 2.76 (1.25-6.08, p-for-trend = 0.005) in the SE-I, 1.90 (1.04-3.40, p-for-trend = 0.005) in the SE-II and 2.07 (1.01-3.13) in the pooled cohorts. The results were consistent across strata defined by sex, age, physical activity, loneliness/poor social network, and morbidity.

CONCLUSIONS

A proinflammatory dietary pattern is associated with depression risk in older adults. Future research should evaluate whether reducing the inflammatory component of diet leads to reduced depression symptoms in this population.

Negative air ion exposure ameliorates depression-like behaviors induced by chronic mild stress in mice

The presence of negative air ions (NAI) is suggested to be a beneficial factor in improving psychological status and used in treating depression as an alternative approach. However, more biological evidence from animal models is needed to ensure the effects of NAI on the mood regulation, through which can facilitate identification of possible underlying mechanisms. In this study, the chronic mild stress (CMS) protocol was used to induce depressive-like behaviors in mice, and the effects of NAI exposure on CMS-induced depression-like behaviors were examined. Thirty-day NAI exposure prevented the CMS-induced depression-like behaviors as shown by the restoration of sucrose preference and reduced immobility time in the tail suspension test. In addition, the elevation of serous corticosterone was present in CMS-treated mice but not existed in those with the NAI exposure. Furthermore, we observed altered ratios of some cytokines secreted by type 1 T helper (Th1) cells and Th2 cells in CMS-treated mice, but it could be restored after NAI exposure. In conclusion, NAI intervention is able to ameliorate CMS-induced depression-like behaviors in mice, and this effect is associated with the alteration of corticosterone and functional rebalance between Th1 and Th2 cells.

HIV Symptom Clusters are Similar Using the Dimensions of Symptom Occurrence and Distress

CONTEXT

People living with HIV infection (PLWH) in the United States continue to experience a high symptom burden despite improvements in antiretroviral therapy.

OBJECTIVES

The purpose of this study was to determine if the number and types of symptom clusters differed based on whether symptom occurrence rates or distress ratings were used to create the clusters.

METHODS

Data from 2,000 patients with complete symptom occurrence rates and distress scores on the 20-item HIV Symptom Index from their first ambulatory clinic visit at one of six national HIV centers of excellence in the Center for AIDS Research Network of Integrated Clinical Systems were used in these analyses. Exploratory factor analysis was used to create the symptom clusters.

RESULTS

The same four symptom clusters (i.e., gastrointestinal, psychological, pain, body image) were identified using occurrence rates and distress ratings. For both dimensions of the symptom experience, the psychological, pain, and body image clusters each had the same symptoms. For the gastrointestinal cluster, four symptoms loaded on the occurrence dimension and six symptoms loaded on the distress dimension.

CONCLUSION

The number and types of symptom clusters were relatively similar across the occurrence and distress dimensions of the symptom experience. Symptom clusters in PLWH may provide insights into the development of targeted interventions for multiple co-occurring symptoms.

Stress-Induced Depression and Alzheimer's Disease: Focus on Astrocytes

Neurodegenerative diseases and depression are multifactorial disorders with a complex and poorly understood physiopathology. Astrocytes play a key role in the functioning of neurons in norm and pathology. Stress is an important factor for the development of brain disorders. Here, we review data on the effects of stress on astrocyte function and evidence of the involvement of astrocyte dysfunction in depression and Alzheimer's disease (AD). Stressful life events are an important risk factor for depression; meanwhile, depression is an important risk factor for AD. Clinical data indicate atrophic changes in the same areas of the brain, the hippocampus and prefrontal cortex (PFC), in both pathologies. These brain regions play a key role in regulating the stress response and are most vulnerable to the action of glucocorticoids. PFC astrocytes are critically involved in the development of depression. Stress alters astrocyte function and can result in pyroptotic death of not only neurons, but also astrocytes. BDNF-TrkB system not only plays a key role in depression and in normalizing the stress response, but also appears to be an important factor in the functioning of astrocytes. Astrocytes, being a target for stress and glucocorticoids, are a promising target for the treatment of stress-dependent depression and AD.

Neutrophil to lymphocyte ratio is a transdiagnostic biomarker of depression and structural and functional brain alterations in older adults

The neutrophil to lymphocyte ratio (N:L) is an emergent transdiagnostic biomarker shown to predict peripheral inflammation as well as neuropsychiatric impairment. The afferent signaling of inflammation to the central nervous system has been implicated in the pathophysiology of sickness behavior and depression. Here, the N:L was compared to structural and functional limbic alterations found concomitant with depression within a geriatric cohort. Venous blood was collected for a complete blood count, and magnetic resonance imaging as well as phenotypic data were collected from the 66 community-dwelling older adults (aged 65-86 years). The N:L was regressed on gray matter volume and resting-state functional connectivity (rsFC) of the subgenual anterior cingulate (sgACC). Thresholded parameter estimates were extracted from structural and functional brain scans and bivariate associations tested with scores on the geriatric depression scale. Greater N:L predicted lower volume of hypothalamus and rsFC of sgACC with ventromedial prefrontal cortex. Both parameters were correlated (p < 0.05) with greater symptomology in those reporting moderate to severe levels of depression. These findings support the N:L as a transdiagnostic biomarker of limbic alteration underpinning mood disturbance in non-treated older adults.

Neurotensin agonist PD 149163 modulates the neuroinflammation induced by bacterial endotoxin lipopolysaccharide in mice model

OBJECTIVE

The disruption of bidirectional communication between neuroendocrine and immune components by stressors leads to mental problems. The immunomodulation therapy of neuroinflammation-led psychiatric illness is an emerging area of research. Therefore, the present study aimed to evaluate immune modulation efficacy of PD 149163 (PD) against the lipopolysaccharide (LPS)-induced neuroinflammation.

MATERIALS AND METHODS

The Swiss albino mice (female/12 weeks) were divided into six groups (6 mice/group): (I) Control: 0.9% NaCl; (II) LPS: 1 mg/kg BW, for 5 days; (III) LPS + PD Low: LPS 1 mg/kg BW (for 5 days) after that PD 100 µg/kg BW (for 21 days); (IV) LPS + PD High: LPS 1 mg/kg BW (for 5 days) after that PD 300 µg/kg BW (for 21 days); (V) PD Low: PD 100 µg/kg BW (for 21 days); (VI) PD High: PD 300 µg/kg BW (for 21 days). All treatments were given intraperitoneal.

RESULTS

The LPS-induced weight loss (body and brain) was normalized to control after PD treatment. The PD enhanced superoxide dismutase (SOD) activity while decreased lipid hydroperoxide (LOOH) level altered in LPS-exposed mice. The significantly increased pro-inflammatory cytokines (IL-6 and TNF-α) in LPS exposure were also decreased by PD. Likewise, the LPS-induced HPA axis activation was stabilized by PD. In the hippocampus, the pyramidal cell layer thickness, pyramidal neurons number and size of CA1 and CA3 regions were reduced along with misalignment, shrinkage, and impairment of cytoarchitecture. In the co-treated group, the LPS-induced hippocampus disruption was reversed after PD exposure.

CONCLUSION

We suggested that the PD modulates the LPS-induced neuroinflammation and psychiatric illness in a dose-dependent manner.

Inhibition of Connexin 36 attenuates HMGB1-mediated depressive-like behaviors induced by chronic unpredictable mild stress

BACKGROUND

High mobility group box 1 (HMGB1) released by neurons and microglia was demonstrated to be an important mediator in depressive-like behaviors induced by chronic unpredictable mild stress (CUMS), which could lead to the imbalance of two different metabolic approaches in kynurenine pathway (KP), thus enhancing glutamate transmission and exacerbating depressive-like behaviors. Evidence showed that HMGB1 signaling might be regulated by Connexin (Cx) 36 in inflammatory diseases of central nervous system (CNS). Our study aimed to further explore the role of Cx36 in depressive-like behaviors and its relationship with HMGB1.

METHODS

After 4-week chronic stress, behavioral tests were conducted to evaluate depressive-like behaviors, including sucrose preference test (SPT), tail suspension test (TST), forced swimming test (FST), and open field test (OFT). Western blot analysis and immunofluorescence staining were used to observe the expression and location of Cx36. Enzyme-linked immunosorbent assay (ELISA) was adopted to detect the concentrations of inflammatory cytokines. And the excitability and inward currents of hippocampal neurons were recorded by whole-cell patch clamping.

RESULTS

The expression of Cx36 was significantly increased in hippocampal neurons of mice exposed to CUMS, while treatment with glycyrrhizinic acid (GZA) or quinine could both down-regulate Cx36 and alleviate depressive-like behaviors. The proinflammatory cytokines like HMGB1, tumor necrosis factor alpha (TNF-α), and interleukin-1β (IL-1β) were all elevated by CUMS, and application of GZA and quinine could decrease them. In addition, the enhanced excitability and inward currents of hippocampal neurons induced by lipopolysaccharide (LPS) could be reduced by either GZA or quinine.

CONCLUSIONS

Inhibition of Cx36 in hippocampal neurons might attenuates HMGB1-mediated depressive-like behaviors induced by CUMS through down-regulation of the proinflammatory cytokines and reduction of the excitability and intracellular ion overload.

Determination of Cutpoints for Symptom Burden in Oncology Patients Receiving Chemotherapy

CONTEXT

Cutpoints can be used as a threshold for screening symptom(s) that warrant intervention(s) and for monitoring patients' responses to these interventions.

OBJECTIVES

In a sample of oncology patients undergoing chemotherapy, study purposes were to determine the optimal cutpoints for low, moderate, and high symptom burden and determine if these cutpoints distinguished among the symptom groups in any demographic, clinical, and stress characteristics, as well as QOL outcomes.

METHODS

Total of 1329 patients completed a modified version of the Memorial Symptom Assessment Scale (38 symptoms). Using the methodology of Serlin and colleagues, cutpoints were created using symptom occurrence rates and cancer-specific quality of life (QOL) scores. Cutpoints were validated using measures of stress and resilience and a generic measure of QOL (i.e., Medical Outcomes Study Short Form 12 (SF-12)).

RESULTS

Of the 25 possible cutpoints evaluated, the optimal cutpoint, with the largest between category F statistic, was CP8,15 (Low = 0-8, Moderate = 9-15, High = 16-38 symptoms). Percentage of patients in the Low, Moderate, and High cutpoint groups were 25.3%, 36.3%, and 38.4%, respectively. Significant differences were found among the symptom burden groups in global, cancer-specific, and cumulative life stress (i.e., Low < Moderate < High) and resilience and SF-12 (i.e., Low > Moderate > High) scores.

CONCLUSION

Our findings provide evidence for clinically meaningful cutpoints that can be used to guide symptom assessment and management. These cutpoints may be used to establish alert thresholds for electronic monitoring of symptoms in oncology patients.

Variability in Behavioral Phenotypes after Forced Swimming-Induced Stress in Rats Is Associated with Expression of the Glucocorticoid Receptor, Nurr1, and IL-1β in the Hippocampus

Individual differences in coping with stress may determine either a vulnerable or resilient phenotype. Therefore, it is important to better understand the biology underlying the behavioral phenotype. We assessed whether individual behavioral phenotype to acute stress is related with the hippocampal expression of glucocorticoid receptor (GR), Nurr1, interleukin-1 beta (IL-1β) or brain-derived neurotrophic factor (BDNF). Wistar male rats were exposed to forced swimming for 15 min and sacrificed at different times. Behavioral response was analyzed, and it was compared with the gene and protein expression of GR, Nurr1, IL-1β and BDNF in the hippocampus for each time point. Behavioral phenotyping showed a group with high immobility (vulnerable) while another had low immobility (resilient). No significant differences were found in the Nurr1, IL-1β and BDNF mRNA levels between resilient and vulnerable rats at different recovery times except for Nr3c1 (gene for GR). However, exposure to stress caused significantly higher levels of GR, Nurr1 and IL-1β proteins of vulnerable compared to resilient rats. This variability of behavioral phenotypes is associated with a differential molecular response to stress that involves GR, Nurr1, and IL-1β as mediators in coping with stress. This contributes to identifying biomarkers of susceptibility to stress.

Astrocytes in depression and Alzheimer's disease

Astrocytes are an abundant subgroup of cells in the central nervous system (CNS) that play a critical role in controlling neuronal circuits involved in emotion, learning, and memory. In clinical cases, multiple chronic brain diseases may cause psychosocial and cognitive impairment, such as depression and Alzheimer's disease (AD). For years, complex pathological conditions driven by depression and AD have been widely perceived to contribute to a high risk of disability, resulting in gradual loss of self-care ability, lower life qualities, and vast burden on human society. Interestingly, correlational research on depression and AD has shown that depression might be a prodrome of progressive degenerative neurological disease. As a kind of multifunctional glial cell in the CNS, astrocytes maintain physiological function via supporting neuronal cells, modulating pathologic niche, and regulating energy metabolism. Mounting evidence has shown that astrocytic dysfunction is involved in the progression of depression and AD. We herein review the current findings on the roles and mechanisms of astrocytes in the development of depression and AD, with an implication of potential therapeutic avenue for these diseases by targeting astrocytes.

Large-scale whole-exome sequencing association study identifies FOXH1 gene and sphingolipid metabolism pathway influencing major depressive disorder

In the present study, we performed an exome-wide investigation of the burden of rare disease-causing variants for major depressive disorder (MDD) using 16,702 samples from UK biobank. Gene-based association analysis and candidate gene prioritization analysis indicated that FOXH1 have significant association with MDD. In addition, sphingolipid metabolism pathway was found to be less enriched with rare disease-causing variants in the MDD group, suggesting that this gene set may be involved in the pathophysiology of MDD.

Epigenetics and the International Classification of Functioning, Disability and Health Model: Bridging Nature, Nurture, and Patient-Centered Population Health

Epigenetic processes enable environmental inputs such as diet, exercise, and health behaviors to reversibly tag DNA with chemical "marks" that increase or decrease the expression of an individual's genetic template. Over time, epigenetic adaptations enable the effects of healthy or unhealthy stresses to become stably expressed in the tissue of an organism, with important consequences for health and disease. New research indicates that seemingly non-biological factors such as social stress, poverty, and childhood hardship initiate epigenetic adaptations in gene pathways that govern inflammation and immunity, two of the greatest contributors to chronic diseases such as diabetes and obesity. Epigenetic processes therefore provide a biological bridge between the genome-an individual's genetic inheritance-and the Social Determinants of Health-the conditions in which they are born, grow, live, work, and age. This Perspective paper argues that physical therapy clinicians, researchers, and educators can use the theoretical framework provided by the International Classification of Functioning, Disability, and Health (ICF model) to harmonize new discoveries from both public health research and medically focused genomic research. The ICF model likewise captures the essential role played by physical activity and exercise, which initiate powerful and widespread epigenetic adaptations that promote health and functioning. In this proposed framework, epigenetic processes transduce the effects of the social determinants of health and behaviors such as exercise into stable biological adaptations that affect an individual's daily activities and their participation in social roles. By harmonizing "nature" and "nurture," physical therapists can approach patient care with a more integrated perspective, capitalizing on novel discoveries in precision medicine, rehabilitation science, and in population-level research. As the experts in physical activity and exercise, physical therapists are ideally positioned to drive progress in the new era of patient-centered population health care.

Investigating Associations Between Depressive Symptoms and Anti-/Pro-Inflammatory Nutrients in an Elderly Population in Northern China: A Bayesian Kernel Machine Regression Approach

Backgroud

The potential for dietary inflammation has been shown to be associated with a variety of chronic diseases. The relationship between the potential for dietary inflammation and depression in the elderly is unclear.

Objective

This study aimed to exam the relationship between different nutrients and the risk of depression symptoms in the elderly.

Methods

In total, 1865 elderly in northern China were investigated at baseline from 2018 to 2019 and followed up in 2020. We measured the baseline intake of 22 nutrients and used Least Absolute Shrinkage and Selection Operator(LASSO) regression analysis and Bayesian Kernel Machine Regression (BKMR) to explore the association between exposure to a variety of nutrients with different inflammatory potentials and the risk of depressive symptoms.

Results

A total of 447 individuals (24.0%) were diagnosed with depressive symptoms. Through the lasso regression model, it was found that 11 nutrients are significantly related to the risk of depressive symptoms, of which 6 nutrients are pro-inflammatory nutrients (inflammation effect score>0), and 5 are anti-inflammatory nutrients (inflammation effect score<0). We incorporated the inflammatory effect scores of 11 nutrients into the BKMR model at the same time, and found that the overall inflammatory effect of 11 nutrients increased with the increase of total inflammatory scores, suggesting that the overall effect was pro-inflammatory. BKMR subgroup analysis shows that whether in the pro-inflammatory nutrient group or the anti-inflammatory nutrient group, multiple nutrients have a significant combined effect on depressive symptoms. By comparing the overall and group effects, we found that the inflammatory effects of the pro-inflammatory diet and the anti-inflammatory diet in the study’s diet are offset by each other (P<0.005).

Conclusion

We determined the combined effect of multiple nutrients of different inflammatory potential classifications on depressive symptoms in the elderly.

Hypothalamus volume and DNA methylation of stress axis genes in major depressive disorder: A CAN-BIND study report

Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis is considered one of the mechanisms underlying the development of major depressive disorder (MDD), but the exact nature of this dysfunction is unknown. We investigated the relationship between hypothalamus volume (HV) and blood-derived DNA methylation in MDD. We obtained brain MRI, clinical and molecular data from 181 unmedicated MDD and 90 healthy control (HC) participants. MDD participants received a 16-week standardized antidepressant treatment protocol, as part of the first Canadian Biomarker Integration Network in Depression (CAN-BIND) study. We collected bilateral HV measures via manual segmentation by two independent raters. DNA methylation and RNA sequencing were performed for three key HPA axis-regulating genes coding for the corticotropin-binding protein (CRHBP), glucocorticoid receptor (NR3C1) and FK506 binding protein 5 (FKBP5). We used elastic net regression to perform variable selection and assess predictive ability of methylation variables on HV. Left HV was negatively associated with duration of current episode (ρ = -0.17, p = 0.035). We did not observe significant differences in HV between MDD and HC or any associations between HV and treatment response at weeks 8 or 16, overall depression severity, illness duration or childhood maltreatment. We also did not observe any differentially methylated CpG sites between MDD and HC groups. After assessing functionality by correlating methylation levels with RNA expression of the respective genes, we observed that the number of functionally relevant CpG sites differed between MDD and HC groups in FKBP5 (χ² = 77.25, p < 0.0001) and NR3C1 (χ² = 7.29, p = 0.007). Cross-referencing functionally relevant CpG sites to those that were highly ranked in predicting HV in elastic net modeling identified one site from FKBP5 (cg03591753) and one from NR3C1 (cg20728768) within the MDD group. Stronger associations between DNA methylation, gene expression and HV in MDD suggest a novel putative molecular pathway of stress-related sensitivity in depression. Future studies should consider utilizing the epigenome and ultra-high field MR data which would allow the investigation of HV sub-fields.

Mechanism and therapeutic strategies of depression after myocardial infarction

Depression resulted as an important factor associated with the myocardial infarction (MI) prognosis. Patients with MI also have a higher risk for developing depression. Although the issue of depression after MI has become a matter of clinical concern, the molecular mechanism underlying depression after MI remains unclear, whereby several strategies suggested have not got ideal effects, such as selective serotonin reuptake inhibitors. In this review, we summarized and discussed the occurrence mechanism of depression after MI, such as 5-hydroxytryptamine (5-HT) dysfunction, altered hypothalamus-pituitary-adrenal (HPA) axis function, gut microbiota imbalance, exosomal signal transduction, and inflammation. In addition, we offered a succinct overview of treatment, as well as some promising molecules especially from natural products for the treatment of depression after MI.

Hypothalamus-skeletal muscle crosstalk during exercise and its role in metabolism modulation

Physical inactivity is a major public health problem that contributes to the development of several pathologies such as obesity, type 2 diabetes and cardiovascular diseases. Regular exercise mitigates the progression of these metabolic problems and contributes positively to memory and behavior. Therefore, public health agencies have incorporated exercise in the treatment of widespread disorders. The hypothalamus, specifically the ventromedial and the arcuate nuclei, responds to exercise activity and modulates energy metabolism through stimulation of the sympathetic nervous system and catecholamine secretion into the circulation. In addition, physical performance enhances cognitive functions and memory, mediated mostly by an increase in brain-derived neurotrophic factor levels in brain. During exercise training, skeletal muscle myofibers remodel their biochemical, morphological and physiological state. Moreover, skeletal muscle interacts with other organs by the release into the circulation of myokines, molecules that exhibit autocrine, paracrine and endocrine functions. Several studies have focused on the role of skeletal muscle and tissues in response to physical activity. However, how the hypothalamus could influence the skeletal muscle task in the context of exercise is less studied. Here, we review recent data about hypothalamus-skeletal muscle crosstalk in response to physical activity and focus on specific aspects such as the neuroendocrinological effects of exercise and the endocrine functions of skeletal muscle, to provide a perspective for future study directions.

Probiotics as a Treatment for "Metabolic Depression"? A Rationale for Future Studies

Depression and metabolic diseases often coexist, having several features in common, e.g., chronic low-grade inflammation and intestinal dysbiosis. Different microbiota interventions have been proposed to be used as a treatment for these disorders. In the paper, we review the efficacy of probiotics in depressive disorders, obesity, metabolic syndrome and its liver equivalent based on the published experimental studies, clinical trials and meta-analyses. Probiotics seem to be effective in reducing depressive symptoms when administered in addition to antidepressants. Additionally, probiotics intake may ameliorate some of the clinical components of metabolic diseases. However, standardized methodology regarding probiotics use in clinical trials has not been established yet. In this narrative review, we discuss current knowledge on the recently used methodology with its strengths and limitations and propose criteria that may be implemented to create a new study of the effectiveness of probiotics in depressive disorders comorbid with metabolic abnormalities. We put across our choice on type of study population, probiotics genus, strains, dosages and formulations, intervention period, as well as primary and secondary outcome measures.

The Effect of Omega-3 Fatty Acids on Thromboxane, Brain-Derived Neurotrophic Factor, Homocysteine, and Vitamin D in Depressive Children and Adolescents: Randomized Controlled Trial

In the DEPOXIN project, we have found that a high ratio of omega-6/omega-3 fatty acids (FA) is associated with worsening of depressive symptoms in children and adolescents with depressive disorder (DD) and that the 12-week omega-3 FA supplementation modulates DD symptoms. Here we present our results of the secondary outcomes: the levels of thromboxane (TXB), brain-derived neurotrophic factor (BDNF), homocysteine (HCy) and vitamin D. Fifty-eight patients were randomized into two arms. One group received a fish oil emulsion enriched with omega-3 FA, and the other received a sunflower oil emulsion containing omega-6 FA, for 12 weeks. Depressive symptoms were evaluated, using the Child's Depressive Inventory (CDI). The patients with DD had elevated TXB levels and decreased vitamin D levels, as compared to healthy controls. Both CDI and omega-6/omega-3 ratio correlated positively with TXB and negatively with BDNF at baseline. Compared to the omega-6 FA group, the supplementation with omega-3 FA for 12 weeks significantly reduced plasma TXB (p = 0.024) and increased BDNF (p = 0.011) levels. No changes in HCy and vitamin D were observed. Our results demonstrate the possible role of TXB and BDNF in the pathophysiology of DD and the benefits of omega-3 FA supplementation. The study was registered with the ISRCTN registry (ISRCTN81655012).

Hypothalamic Inflammation as a Potential Pathophysiologic Basis for the Heterogeneity of Clinical, Hormonal, and Metabolic Presentation in PCOS

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age. It is a heterogeneous condition characterized by reproductive, endocrine, metabolic, and psychiatric abnormalities. More than one pathogenic mechanism is involved in its development. On the other hand, the hypothalamus plays a crucial role in many important functions of the body, including weight balance, food intake, and reproduction. A high-fat diet with a large amount of long-chain saturated fatty acids can induce inflammation in the hypothalamus. Hypothalamic neurons can sense extracellular glucose concentrations and participate, with a feedback mechanism, in the regulation of whole-body glucose homeostasis. When consumed nutrients are rich in fat and sugar, and these regulatory mechanisms can trigger inflammatory pathways resulting in hypothalamic inflammation. The latter has been correlated with metabolic diseases, obesity, and depression. In this review, we explore whether the pattern and the expansion of hypothalamic inflammation, as a result of a high-fat and -sugar diet, may contribute to the heterogeneity of the clinical, hormonal, and metabolic presentation in PCOS via pathophysiologic mechanisms affecting specific areas of the hypothalamus. These mechanisms could be potential targets for the development of effective therapies for the treatment of PCOS.

Adiposity in Depression or Depression in Adiposity? The Role of Immune-Inflammatory-Microbial Overlap

Some of the most common and debilitating conditions are metabolic disorders (metabolic syndrome and non-alcoholic fatty liver disease) and depression. These conditions are also exacerbated by the fact that they often co-occur. Although the exact mechanisms underlying such relationships are poorly known, antipsychotic medication and antidepressant use, diet and physical activity, and lifestyle factors are believed to play a role; however, their high co-occurrence rate suggests a possible pathophysiological overlap. This paper reviews several possible bases for this overlap, including hypothalamic-pituitary-adrenal axis dysregulation, immune alterations with chronic inflammation, and oxidative stress. While it is entirely possible that changes in the microbiota may play a role in each of them, interventions based on the implementation of dietary and other lifestyle changes, supplementation with prebiotics or probiotics and faecal microbiota transplantation have failed to achieve conclusive results. A better characterization of the above associations may allow a more targeted approach to the treatment of both depressive and metabolic disorders. The paper also presents several practical applications for future studies.

Role of Oxidative Stress and Neuroinflammation in Attention-Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder of childhood. Although abnormalities in several brain regions and disturbances of the catecholaminergic pathway have been demonstrated, the pathophysiology of ADHD is not completely understood, but as a multifactorial disorder, has been associated with an increase in oxidative stress and neuroinflammation. This review presents an overview of factors that increase oxidative stress and neuroinflammation. The imbalance between oxidants and antioxidants and also the treatment with medications are two factors that can increase oxidative damage, whereas the comorbidity between ADHD and inflammatory disorders, altered immune response, genetic and environmental associations, and polymorphisms in inflammatory-related genes can increase neuroinflammation. Evidence of an association with these factors has become valuable for research on ADHD. Such evidence opens up new intervention routes for the use of natural products as antioxidants that could have potential as a treatment against oxidative stress and neuroinflammation in ADHD.

Stress and coping in women with breast cancer:unravelling the mechanisms to improve resilience

Breast cancer diagnosis, surgery, adjuvant therapies and survivorship can all be extremely stressful. In women, concerns about body image are common as a result of the disease and can affect interpersonal relationships, possibly leading to social isolation, increasing the likelihood for mood disorders. This is particularly relevant as women are at greater risk to develop anxiety and depressive symptoms in response to highly stressful situations. Here we address the mechanisms and the pathways activated as a result of stress and contributing to changes in the pathophysiology of breast cancer, as well as the potential of stress management factors and interventions in buffering the deleterious effects of chronic stress in a gender perspective. An improved understanding of the biological mechanisms linking stress-management resources to health-relevant biological processes in breast cancer patients could reveal novel therapeutic targets and help clarifying which psychosocial interventions can improve cancer outcomes, ultimately offering a unique opportunity to improve contemporary cancer treatments.