Is Dysregulation of the HPA-Axis a Core Pathophysiology Mediating Co-Morbid Depression in Neurodegenerative Diseases?

A Potential Role for MAGI-1 in the Bi-Directional Relationship Between Major Depressive Disorder and Cardiovascular Disease

PURPOSE OF REVIEW

Major Depressive Disorder (MDD) is characterized by persistent symptoms such as fatigue, loss of interest in activities, feelings of sadness and worthlessness. MDD often coexist with cardiovascular disease (CVD), yet the precise link between these conditions remains unclear. This review explores factors underlying the development of MDD and CVD, including genetic, epigenetic, platelet activation, inflammation, hypothalamic-pituitary-adrenal (HPA) axis activation, endothelial cell (EC) dysfunction, and blood-brain barrier (BBB) disruption.

RECENT FINDINGS

Single nucleotide polymorphisms (SNPs) in the membrane-associated guanylate kinase WW and PDZ domain-containing protein 1 (MAGI-1) are associated with neuroticism and psychiatric disorders including MDD. SNPs in MAGI-1 are also linked to chronic inflammatory disorders such as spontaneous glomerulosclerosis, celiac disease, ulcerative colitis, and Crohn's disease. Increased MAGI-1 expression has been observed in colonic epithelial samples from Crohn's disease and ulcerative colitis patients. MAGI-1 also plays a role in regulating EC activation and atherogenesis in mice and is essential for Influenza A virus (IAV) infection, endoplasmic reticulum stress-induced EC apoptosis, and thrombin-induced EC permeability. Despite being understudied in human disease; evidence suggests that MAGI-1 may play a role in linking CVD and MDD. Therefore, further investigation of MAG-1 could be warranted to elucidate its potential involvement in these conditions.

The Relationship between Canine Behavioral Disorders and Gut Microbiome and Future Therapeutic Perspectives

Canine behavioral disorders have become one of the most common concerns and challenging issues among dog owners. Thus, there is a great demand for knowledge about various factors affecting dogs' emotions and well-being. Among them, the gut-brain axis seems to be particularly interesting, especially since in many instances the standard treatment or behavioral therapies insufficiently improve animal behavior. Therefore, to face this challenge, the search for novel therapeutic methods is highly required. Existing data show that mammals' gut microbiome, immune system, and nervous system are in continuous communication and influence animal physiology and behavior. This review aimed to summarize and discuss the most important scientific evidence on the relationship between mental disorders and gut microbiota in dogs, simultaneously presenting comparable outcomes in humans and rodent models. A comprehensive overview of crucial mechanisms of the gut-brain axis is included. This refers especially to the neurotransmitters crucial for animal behavior, which are regulated by the gut microbiome, and to the main microbial metabolites-short-chain fatty acids (SCFAs). This review presents summarized data on gut dysbiosis in relation to the inflammation process within the organism, as well as the activation of the hypothalamic-pituitary-adrenal (HPA) axis. All of the above mechanisms are presented in this review in strict correlation with brain and/or behavioral changes in the animal. Additionally, according to human and laboratory animal studies, the gut microbiome appears to be altered in individuals with mental disorders; thus, various strategies to manipulate the gut microbiota are implemented. This refers also to the fecal microbiome transplantation (FMT) method, based on transferring the fecal matter from a donor into the gastrointestinal tract of a recipient in order to modulate the gut microbiota. In this review, the possible effects of the FMT procedure on animal behavioral disorders are discussed.

Rethinking neurodegenerative diseases: neurometabolic concept linking lipid oxidation to diseases in the central nervous system

ABSTRACT

Currently, there is a lack of effective medicines capable of halting or reversing the progression of neurodegenerative disorders, including amyotrophic lateral sclerosis, Parkinson's disease, multiple sclerosis, or Alzheimer's disease. Given the unmet medical need, it is necessary to reevaluate the existing paradigms of how to target these diseases. When considering neurodegenerative diseases from a systemic neurometabolic perspective, it becomes possible to explain the shared pathological features. This innovative approach presented in this paper draws upon extensive research conducted by the authors and researchers worldwide. In this review, we highlight the importance of metabolic mitochondrial dysfunction in the context of neurodegenerative diseases. We provide an overview of the risk factors associated with developing neurodegenerative disorders, including genetic, epigenetic, and environmental factors. Additionally, we examine pathological mechanisms implicated in these diseases such as oxidative stress, accumulation of misfolded proteins, inflammation, demyelination, death of neurons, insulin resistance, dysbiosis, and neurotransmitter disturbances. Finally, we outline a proposal for the restoration of mitochondrial metabolism, a crucial aspect that may hold the key to facilitating curative therapeutic interventions for neurodegenerative disorders in forthcoming advancements.

Alpha-synuclein-induced stress sensitivity renders the Parkinson's disease brain susceptible to neurodegeneration

A link between chronic stress and Parkinson's disease (PD) pathogenesis is emerging. Ample evidence demonstrates that the presynaptic neuronal protein alpha-synuclein (asyn) is closely tied to PD pathogenesis. However, it is not known whether stress system dysfunction is present in PD, if asyn is involved, and if, together, they contribute to neurodegeneration. To address these questions, we assess stress axis function in transgenic rats overexpressing full-length wildtype human asyn (asyn BAC rats) and perform multi-level stress and PD phenotyping following chronic corticosterone administration. Stress signaling, namely corticotropin-releasing factor, glucocorticoid and mineralocorticoid receptor gene expression, is also examined in post-mortem PD patient brains. Overexpression of human wildtype asyn leads to HPA axis dysregulation in rats, while chronic corticosterone administration significantly aggravates nigrostriatal degeneration, serine129 phosphorylated asyn (pS129) expression and neuroinflammation, leading to phenoconversion from a prodromal to an overt motor PD phenotype. Interestingly, chronic corticosterone in asyn BAC rats induces a robust, twofold increase in pS129 expression in the hypothalamus, the master regulator of the stress response, while the hippocampus, both a regulator and a target of the stress response, also demonstrates elevated pS129 asyn levels and altered markers of stress signalling. Finally, defective hippocampal stress signalling is mirrored in human PD brains and correlates with asyn expression levels. Taken together, our results link brain stress system dysregulation with asyn and provide evidence that elevated circulating glucocorticoids can contribute to asyn-induced neurodegeneration, ultimately triggering phenoconversion from prodromal to overt PD.

Prevalence and factors associated with dyslipidemia in patients with first hospitalization for major depressive disorder: a large sample cross-sectional study

BACKGROUND

Major depressive disorder (MDD) is a severe mental illness with high relapse rates and high mortality. Depression not only severely limits psychosocial functioning but also reduces quality of life. It can also negatively affect patients' clinical parameters, including lipid metabolism markers. This study aimed to investigate the prevalence and risk factors of hyperlipidemia (HL) in patients with MDD who were hospitalized for the first time.

METHODS

In this study, we enrolled 981 patients with MDD who were hospitalized for the first time, collected their demographic data and biochemical indicators, and evaluated their clinical symptoms. We divided the patients into HL and non-HL subgroups based on whether they had co-morbid HL. We compared whether there were significant differences between the two groups regarding demographics and general clinical information.

RESULTS

A total of 708 of 981 MDD patients were described as being in the hyperlipidemic group, with an incidence of 72.17%. Clinical Global Impression Scale-Severity of Illness (CGI-SI) score and Hamilton Depression Scale (HAMD) score are risk factors for co-morbid HL in patients with MDD. The area under the ROC curve for the CGI-SI and HAMD score and their combined discriminatory ability was approximately 63%, 67%, and 68%, respectively.

CONCLUSION

The prevalence of HL was high in patients with MDD who were first hospitalized; Higher HAMD score and CGI-SI score were risk factors for the development of HL in MDD; The HAMD score and the CGI-SI score are predictive of the severity of HL.

Mechanisms Involved in the Link between Depression, Antidepressant Treatment, and Associated Weight Change

Major depressive disorder is a severe mood disorder associated with a marked decrease in quality of life and social functioning, accompanied by a risk of suicidal behavior. Therefore, seeking out and adhering to effective treatment is of great personal and society-wide importance. Weight changes associated with antidepressant therapy are often cited as the reason for treatment withdrawal and thus are an important topic of interest. There indeed exists a significant mechanistic overlap between depression, antidepressant treatment, and the regulation of appetite and body weight. The suggested pathomechanisms include the abnormal functioning of the homeostatic (mostly humoral) and hedonic (mostly dopaminergic) circuits of appetite regulation, as well as causing neuromorphological and neurophysiological changes underlying the development of depressive disorder. However, this issue is still extensively discussed. This review aims to summarize mechanisms linked to depression and antidepressant therapy in the context of weight change.

Social isolation and the risk of Parkinson disease in the UK biobank study

Parkinson disease (PD) has become one of the most rapidly growing causes of disability among the older population and social isolation is a major concern in the PD community. However, the relationship between social isolation and future risk of PD remains unclear. This study included 192,340 participants aged 60 or older who were free of dementia and PD at baseline from the UK Biobank study. Social isolation was measured using a composite score derived from three questions on number in household, frequency of friend/family visits, and leisure/social activities. Incident PD cases were identified through electronic health records. Multivariable-adjusted Cox regression models were used to compute the hazard ratio (HR) and 95% confidence interval (CI). Among the 192,340 participants (mean [standard deviation] age, 64.2 [2.9] years; 103,253 [53.7%] women), 89,075 (46.3%) participants were in the least isolated group and 26,161 (13.6%) were in the most isolated group. Over a median follow-up of 12.5 years, 2048 incident PD cases were documented. Compared to the least isolated group, the multivariable-adjusted HRs (95% CIs) for PD were 1.00 (0.91-1.10) for the moderately isolated group and 1.19 (1.05-1.36) for the most isolated group (P-trend = 0.04). The observed association was independent of the genetic susceptibility to PD and consistent in subgroup analyses. Social isolation was associated with a higher risk of PD regardless of genetic risk. Our findings highlighted the importance of developing screening and intervention strategies for social isolation among older adults to reduce the risk of PD.

Sex-Specific Differences and the Role of Environmental Enrichment in the Expression of Hippocampal CB1 Receptors following Chronic Unpredictable Stress

Stress-related mental disorders have become increasingly prevalent, thus endangering mental health worldwide. Exploring stress-associated brain alterations is vital for understanding the possible neurobiological mechanisms underlying these changes. Based on existing evidence, the brain endogenous cannabinoid system (ECS) plays a significant role in the stress response, and disruptions in its function are associated with the neurobiology of various stress-related disorders. This study primarily focuses on investigating the impact of chronic unpredictable stress (CUS) on the expression of hippocampal cannabinoid type 1 (CB1) receptors, part of the ECS, in adult male and female Wistar rats. Additionally, it explores whether environmental enrichment (EE) initiated during adolescence could mitigate the CUS-associated alterations in CB1 expression. Wistar rats, shortly after weaning, were placed in either standard housing (SH) or EE conditions for a duration of 10 weeks. On postnatal day 66, specific subgroups of SH or EE animals underwent a 4-week CUS protocol. Western blot (WB) analysis was conducted in the whole hippocampus of the left brain hemisphere to assess total CB1 protein expression, while immunohistochemistry (IHC) was performed on the right hemisphere to estimate the expression of CB1 receptors in certain hippocampal areas (i.e., CA1, CA3 and dentate gyrus-DG). The WB analysis revealed no statistically significant differences in total CB1 protein levels among the groups; however, reduced CB1 expression was found in specific hippocampal sub-regions using IHC. Specifically, CUS significantly decreased CB1 receptor expression in the CA1 and DG of both sexes, whereas in CA3 the CUS-associated decrease was limited to SH males. Interestingly, EE housing proved protective against these reductions. These findings suggest a region and sex-specific endocannabinoid response to chronic stress, emphasizing the role of positive early experiences in the protection of the adolescent brain against adverse conditions later in life.

Dietary Marine Hydrolysate Improves Memory Performance and Social Behavior through Gut Microbiota Remodeling during Aging

Aging is characterized by a decline in social behavior and cognitive functions leading to a decrease in life quality. In a previous study, we show that a fish hydrolysate supplementation prevents age-related decline in spatial short-term memory and long-term memory and anxiety-like behavior and improves the stress response in aged mice. The aim of this study was to determine the effects of a fish hydrolysate enriched with EPA/DHA or not on the cognitive ability and social interaction during aging and the biological mechanisms involved. We showed for the first time that a fish hydrolysate enriched with EPA/DHA or not improved memory performance and preference for social novelty that were diminished by aging. These changes were associated with the modulation of the gut microbiota, normalization of corticosterone, and modulation of the expression of genes involved in the mitochondrial respiratory chain, circadian clock, neuroprotection, and antioxidant activity. Thus, these changes may contribute to the observed improvements in social behavior and memory and reinforced the innovative character of fish hydrolysate in the prevention of age-related impairments.

Anxiety and Alzheimer's disease pathogenesis: focus on 5-HT and CRF systems in 3xTg-AD and TgF344-AD animal models

Dementia remains one of the leading causes of morbidity and mortality in older adults. Alzheimer's disease (AD) is the most common type of dementia, affecting over 55 million people worldwide. AD is characterized by distinct neurobiological changes, including amyloid-beta protein deposits and tau neurofibrillary tangles, which cause cognitive decline and subsequent behavioral changes, such as distress, insomnia, depression, and anxiety. Recent literature suggests a strong connection between stress systems and AD progression. This presents a promising direction for future AD research. In this review, two systems involved in regulating stress and AD pathogenesis will be highlighted: serotonin (5-HT) and corticotropin releasing factor (CRF). Throughout the review, we summarize critical findings in the field while discussing common limitations with two animal models (3xTg-AD and TgF344-AD), novel pharmacotherapies, and potential early-intervention treatment options. We conclude by highlighting promising future pharmacotherapies and translational animal models of AD and anxiety.

Aerobic Exercise Improves Depressive-like Behavior in CUMS-Induced Rats via the SIRT3/ROS/NLRP3 Signaling Pathway

OBJECTIVE

This study aimed to investigate the effect of exercise on depressive-like behavior induced by chronic unpredictable mild stress (CUMS) in rats and to explore the role of the SIRT3/ROS/NLRP3 signaling pathway in this process.

METHODS

Twenty-nine male 8-week-old Sprague Dawley rats were divided into a control group (CON) (nine rats) and a model group (twenty rats). Thirteen chronic stress stimuli were randomly applied once or twice per day for 35 days to induce depression in the model group rats. After the model was established, the model group rats were randomly divided into the CUMS group (CUMS) and the aerobic exercise + CUMS group (EX + CUMS). The EX + CUMS group received 8 weeks of aerobic exercise intervention for 6 days per week. Behavioral assessments were performed using the sucrose preference test and forced swimming test. The expression of SIRT3, NLRP3, IL-1β, and IL-18 in the hippocampus was detected using RT-PCR. The ROS level in the hippocampus was detected using immunofluorescence. The protein levels of SIRT3 and NLRP3 in the hippocampus were detected using western blotting. The protein levels of IL-1β and IL-18 in the hippocampus were measured using ELISA.

RESULTS

After 5 weeks of chronic stress stimuli, the hippocampal function of rats in the CUMS model group was impaired, and their sucrose preference was reduced, while their forced swimming time was prolonged. The expression of SIRT3 decreased, ROS increased, and the expression of NLRP3 and the levels of IL-1β and IL-18 increased. Aerobic exercise increased the sucrose preference of rats, shortened their immobility time, increased the expression of SIRT3, and reduced the levels of ROS, NLRP3, IL-1β, and IL-18.

CONCLUSION

Exercise can improve the depressive behavior of CUMS model rats, and its mechanism may be related to the upregulation of SIRT3 in the hippocampus, which plays an anti-inflammatory role.

Effects of Fructose and Palmitic Acid on Gene Expression in Drosophila melanogaster Larvae: Implications for Neurodegenerative Diseases

One of the largest health problems worldwide is the development of chronic noncommunicable diseases due to the consumption of hypercaloric diets. Among the most common alterations are cardiovascular diseases, and a high correlation between overnutrition and neurodegenerative diseases has also been found. The urgency in the study of specific damage to tissues such as the brain and intestine led us to use Drosophila melanogaster to study the metabolic effects caused by the consumption of fructose and palmitic acid in specific tissues. Thus, third instar larvae (96 ± 4 h) of the wild Canton-S strain of D. melanogaster were used to perform transcriptomic profiling in brain and midgut tissues to test for the potential metabolic effects of a diet supplemented with fructose and palmitic acid. Our data infer that this diet can alter the biosynthesis of proteins at the mRNA level that participate in the synthesis of amino acids, as well as fundamental enzymes for the dopaminergic and GABAergic systems in the midgut and brain. These also demonstrated alterations in the tissues of flies that may help explain the development of various reported human diseases associated with the consumption of fructose and palmitic acid in humans. These studies will not only help to better understand the mechanisms by which the consumption of these alimentary products is related to the development of neuronal diseases but may also contribute to the prevention of these conditions.

Exploring the potential of mindfulness-based therapy in the prevention and treatment of neurodegenerative diseases based on molecular mechanism studies

Neurodegenerative diseases (ND) have received increasing attention due to their irreversibility, but there is still no means to completely cure ND in clinical practice. Mindfulness therapy (MT), including Qigong, Tai Chi, meditation, and yoga, etc., has become an effective complementary treatment modality in solving clinical and subclinical problems due to its advantages of low side effects, less pain, and easy acceptance by patients. MT is primarily used to treat mental and emotional disorders. In recent years, evidence has shown that MT has a certain therapeutic effect on ND with a potential molecular basis. In this review, we summarize the pathogenesis and risk factors of Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), relating to telomerase activity, epigenetics, stress, and the pro-inflammatory transcription factor nuclear factor kappa B (NF-κB) mediated inflammatory response, and analyze the molecular mechanism basis of MT to prevent and treat ND, to provide possible explanations for the potential of MT treatments for ND.

Modelling acute glucocorticoid transcriptome response in human embryonic stem cell derived neural cultures

Our goal is to demonstrate and characterize acute glucocorticoid transcriptome response in human embryonic stem cell (hESC) derived neural cultures. Toward this, we confirmed the differentiation of hESC lines H9 and H1 into post-mitotic neurons and astrocytes, in addition to the expressions of glucocorticoid receptor (GR) protein, and the GR co-chaperone FK506 binding protein 51 (FKBP5). In a series of experiments in hESC-derived neural cultures treated with dexamethasone (Dex) for 6 h, glucocorticoid hormone (GH) response was detected through the transcriptional upregulation of GH-responsive genes, FKBP5 and PER1. Both genes responded to Dex treatment in a dose-dependent fashion, and FKBP5 protein was significantly upregulated after a 12-hour Dex exposure. We additionally examined the transcriptome-wide effects of acute GH exposure in hESC-derived cultures and identified FKBP5 as the most highly up-regulated gene. We identified 30 additional differentially expressed (DE) genes common to cultures derived from both H9 and H1 hESCs whose expression levels changed in both lines with similar magnitudes and direction.

Putative pathological mechanisms of late-life depression and Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterized by progressive impairment in cognition and memory. AD is accompanied by several neuropsychiatric symptoms, with depression being the most prominent. Although depression has long been known to be associated with AD, controversial findings from preclinical and clinical studies have obscured the precise nature of this association. However recent evidence suggests that depression could be a prodrome or harbinger of AD. Evidence indicates that the major central serotonergic nucleus-the dorsal raphe nucleus (DRN)-shows very early AD pathology: neurofibrillary tangles made of hyperphosphorylated tau protein and degenerated neurites. AD and depression share common pathophysiologies, including functional deficits of the serotonin (5-HT) system. 5-HT receptors have modulatory effects on the progression of AD pathology i.e., reduction in Aβ load, increased hyper-phosphorylation of tau, decreased oxidative stress etc. Moreover, preclinical models show a role for specific channelopathies that result in abnormal regional activational and neuroplasticity patterns. One of these concerns the pathological upregulation of the small conductance calcium-activated potassium (SK) channel in corticolimbic structure. This has also been observed in the DRN in both diseases. The SKC is a key regulator of cell excitability and long-term potentiation (LTP). SKC over-expression is positively correlated with aging and cognitive decline, and is evident in AD. Pharmacological blockade of SKCs has been reported to reverse symptoms of depression and AD. Thus, aberrant SKC functioning could be related to depression pathophysiology and diverts its late-life progression towards the development of AD. We summarize findings from preclinical and clinical studies suggesting a molecular linkage between depression and AD pathology. We also provide a rationale for considering SKCs as a novel pharmacological target for the treatment of AD-associated symptoms.

Low serum uric acid levels may be a potential biomarker of poor sleep quality in patients with Parkinson's disease

BACKGROUND

Sleep disorders are common non-motor symptoms in patients with Parkinson's disease (PD). However, the pathogenesis of sleep disorders in PD patients remains unclear. Previous studies have implicated oxidative stress in sleep disorders associated with PD. Considering uric acid (UA) acts as a natural antioxidant, in this study, we aimed to assess the use of serum UA as a potential biomarker of sleep disorder in PD patients.

METHODS

This study recruited 149 PD patients and 84 Age- and sex-matched individuals. According to the Pittsburgh Sleep Quality Index (PSQI) score, PD patients were divided into three groups, good (≤5), intermediate (6-10), and poor (>10). Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were also performed to identify clinical features and serum UA levels that help establish an accurate diagnostic model for poor sleep quality in PD patients.

RESULTS

PD patients who experienced poor sleep quality had lower serum UA levels. PSQI scores have significant negative relationships with serum UA levels and significant positive relationships with Hamilton Depression Scale (HAMD) scores in PD. Poor sleep quality was independently associated with serum UA levels and HAMD scores. A serum UA level of 328.7 μmol/L and HAMD scores of 19.5 could distinguish PD patients with poor or intermediate sleep to a certain extent, sensitivity of 79.4% and specificity of 76.6%.

CONCLUSIONS

Low serum UA levels may correlate with the severity of sleep disorder in PD patients and may serve as a biomarker for poor sleep quality in PD.

Rationale for a Multi-Factorial Approach for the Reversal of Cognitive Decline in Alzheimer's Disease and MCI: A Review

Alzheimer's disease (AD) is a multifactorial, progressive, neurodegenerative disease typically characterized by memory loss, personality changes, and a decline in overall cognitive function. Usually manifesting in individuals over the age of 60, this is the most prevalent type of dementia and remains the fifth leading cause of death among Americans aged 65 and older. While the development of effective treatment and prevention for AD is a major healthcare goal, unfortunately, therapeutic approaches to date have yet to find a treatment plan that produces long-term cognitive improvement. Drugs that may be able to slow down the progression rate of AD are being introduced to the market; however, there has been no previous solution for preventing or reversing the disease-associated cognitive decline. Recent studies have identified several factors that contribute to the progression and severity of the disease: diet, lifestyle, stress, sleep, nutrient deficiencies, mental health, socialization, and toxins. Thus, increasing evidence supports dietary and other lifestyle changes as potentially effective ways to prevent, slow, or reverse AD progression. Studies also have demonstrated that a personalized, multi-therapeutic approach is needed to improve metabolic abnormalities and AD-associated cognitive decline. These studies suggest the effects of abnormalities, such as insulin resistance, chronic inflammation, hypovitaminosis D, hormonal deficiencies, and hyperhomocysteinemia, in the AD process. Therefore a personalized, multi-therapeutic program based on an individual's genetics and biochemistry may be preferable over a single-drug/mono-therapeutic approach. This article reviews these multi-therapeutic strategies that identify and attenuate all the risk factors specific to each affected individual. This article systematically reviews studies that have incorporated multiple strategies that target numerous factors simultaneously to reverse or treat cognitive decline. We included high-quality clinical trials and observational studies that focused on the cognitive effects of programs comprising lifestyle, physical, and mental activity, as well as nutritional aspects. Articles from PubMed Central, Scopus, and Google Scholar databases were collected, and abstracts were reviewed for relevance to the subject matter. Epidemiological, pathological, toxicological, genetic, and biochemical studies have all concluded that AD represents a complex network insufficiency. The research studies explored in this manuscript confirm the need for a multifactorial approach to target the various risk factors of AD. A single-drug approach may delay the progression of memory loss but, to date, has not prevented or reversed it. Diet, physical activity, sleep, stress, and environment all contribute to the progression of the disease, and, therefore, a multi-factorial optimization of network support and function offers a rational therapeutic strategy. Thus, a multi-therapeutic program that simultaneously targets multiple factors underlying the AD network may be more effective than a mono-therapeutic approach.

Common Neuropsychiatric S ymptoms in Alzheimer's Disease, Mild Cognitive Impairment, and Subjective Memory Complaints: A Unified Framework

The Alzheimer's disease (AD) continuum is a unique spectrum of cognitive impairment that typically involves the stages of subjective memory complaints (SMC), mild cognitive impairment (MCI), and AD dementia. Neuropsychiatric symptoms (NPS), such as apathy, anxiety, stress, and depression, are highly common throughout the AD continuum. However, there is a dearth of research on how these NPS vary across the AD continuum, especially SMC. There is also disagreement on the effects of specific NPS on each stage of the AD continuum due to their collinearity with other NPS, cognitive decline, and environmental factors (e.g., stress). In this article, we conduct a novel perspective review of the scientific literature to understand the presence of NPS across the AD continuum. Specifically, we review the effects of apathy, depression, anxiety, and stress in AD, MCI, and SMC. We then build on this knowledge by proposing two theories of NPS' occurrence across the AD continuum. Consequently, we highlight the current landscape, limitations (e.g., differing operationalization), and contentions surrounding the NPS literature. We also outline theories that could clear up contention and inspire future NPS research.

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.

Acupuncture treatment for post-stroke depression: Intestinal microbiota and its role

Stroke-induced depression is a common complication and an important risk factor for disability. Besides psychiatric symptoms, depressed patients may also exhibit a variety of gastrointestinal symptoms, and even take gastrointestinal symptoms as the primary reason for medical treatment. It is well documented that stress may disrupt the balance of the gut microbiome in patients suffering from post-stroke depression (PSD), and that disruption of the gut microbiome is closely related to the severity of the condition in depressed patients. Therefore, maintaining the balance of intestinal microbiota can be the focus of research on the mechanism of acupuncture in the treatment of PSD. Furthermore, stroke can be effectively treated with acupuncture at all stages and it may act as a special microecological regulator by regulating intestinal microbiota as well. In this article, we reviewed the studies on changing intestinal microbiota after acupuncture treatment and examined the existing problems and development prospects of acupuncture, microbiome, and poststroke depression, in order to provide new ideas for future acupuncture research.

Role of Brain-Gut-Microbiota Axis in Depression: Emerging Therapeutic Avenues

The human gut microbiota plays a significant role in the pathophysiology of central nervous system-related diseases. Recent studies suggest correlations between the altered gut microbiota and major depressive disorder (MDD). It is proposed that normalization of the gut microbiota alleviates MDD. The imbalance of brain-gut-microbiota axis also results in dysregulation of the hypothalamicpituitary- adrenal (HPA) axis. This imbalance has a crucial role in the pathogenesis of depression. Treatment strategies with certain antibiotics lead to the depletion of useful microbes and thereby induce depression like effects in subjects. Microbiota is also involved in the synthesis of various neurotransmitters (NTs) like 5-hydroxy tryptamine (5-HT; serotonin), norepinephrine (NE) and dopamine (DA). In addition to NTs, the gut microbiota also has an influence on brain derived neurotrophic factor (BDNF) levels. Recent research findings have exhibited that transfer of stress prone microbiota in mice is also responsible for depression and anxiety-like behaviour in animals. The use of probiotics, prebiotics, synbiotics and proper diet have shown beneficial effects in the regulation of depression pathogenesis. Moreover, transplantation of fecal microbiota from depressed individuals to normal subjects also induces depression-like symptoms. With the precedence of limited therapeutic benefits from monoamine targeting drugs, the regulation of brain-gut microbiota is emerging as a new treatment modality for MDDs. In this review, we elaborate on the significance of brain-gut-microbiota axis in the progression of MDD, particularly focusing on the modulation of the gut microbiota as a mode of treating MDD.

Evolutionarily conserved gene expression patterns for affective disorders revealed using cross-species brain transcriptomic analyses in humans, rats and zebrafish

Widespread, debilitating and often treatment-resistant, depression and other stress-related neuropsychiatric disorders represent an urgent unmet biomedical and societal problem. Although animal models of these disorders are commonly used to study stress pathogenesis, they are often difficult to translate across species into valuable and meaningful clinically relevant data. To address this problem, here we utilized several cross-species/cross-taxon approaches to identify potential evolutionarily conserved differentially expressed genes and their sets. We also assessed enrichment of these genes for transcription factors DNA-binding sites down- and up- stream from their genetic sequences. For this, we compared our own RNA-seq brain transcriptomic data obtained from chronically stressed rats and zebrafish with publicly available human transcriptomic data for patients with major depression and their respective healthy control groups. Utilizing these data from the three species, we next analyzed their differential gene expression, gene set enrichment and protein-protein interaction networks, combined with validated tools for data pooling. This approach allowed us to identify several key brain proteins (GRIA1, DLG1, CDH1, THRB, PLCG2, NGEF, IKZF1 and FEZF2) as promising, evolutionarily conserved and shared affective 'hub' protein targets, as well as to propose a novel gene set that may be used to further study affective pathogenesis. Overall, these approaches may advance cross-species brain transcriptomic analyses, and call for further cross-species studies into putative shared molecular mechanisms of affective pathogenesis.

Self-reported history of comorbidities and markers of ovarian reserve among subfertile women

PURPOSE

To investigate whether history of comorbidities is associated with markers of ovarian reserve among subfertile women.

METHODS

This observational study includes 645 women seeking fertility care at the Massachusetts General Hospital who enrolled in the Environment and Reproductive Health (EARTH) study (2005-2019). Women completed a comprehensive questionnaire including medical diagnosis of comorbidities. Ovarian reserve markers including antral follicle count (AFC), assessed by transvaginal ultrasound, and circulating serum levels of day 3 FSH and AMH, are assessed by immunoassays. We fit linear regression models to evaluate the association between history of comorbidities and markers of ovarian reserve while adjusting for confounders.

RESULTS

Self-reported history of hypertension, cancer, and neurological disorders was negatively associated with AFC in unadjusted models and in adjusted models for age, smoking, physical activity, comorbidity count, and BMI. Adjusted mean AFC (95% CI) was lower among women with history of hypertension, compared to women with no self-reported history of hypertension (11.5 vs 15.6, p value 0.0001). In contrast, day 3 FSH levels were positively related to history of eating disorders in both unadjusted and adjusted models (10.8 vs. 7.43 IU/L, p value ≤ 0.0001). Self-reported history of other comorbidities was unrelated to AFC, day 3 FSH, and AMH levels.

CONCLUSIONS

History of hypertension, cancer, and neurological disorders was negatively associated with AFC, and eating disorders were positively related to day 3 FSH levels. The prevention of common comorbidities among women in reproductive age may help increase women's fertility given the declining birth rates and increasing use of assisted reproductive technologies in the past years.

Plasma Amyloid-β dynamics in late-life major depression: a longitudinal study

Depressed individuals are twice as likely to develop Alzheimer's disease (AD) as compared to controls. Brain amyloid-β (Aβ) deposition is believed to have a major role in AD pathogenesis but studies also suggest associations of Aβ dynamics and depression. The aim of this study was to test if plasma Aβ levels are longitudinally associated to late-life depression. We measured plasma levels of amyloid-β_1-40 (Aβ40) and amyloid-β_1-42 (Aβ42) peptides longitudinally for three consecutive years in 48 cognitively intact elderly subjects with late-life major depressive disorder (LLMD) and 45 age-matched cognitively healthy controls. We found that the Aβ42/Aβ40 plasma ratio was significantly and steadily lower in depressed subjects compared to controls (p < 0.001). At screening, Aβ42/Aβ40 plasma did not correlate with depression severity (as measured with Hamilton Depression Scale) or cognitive performance (as measured with Mini-Mental State Examination) but was associated to depression severity at 3 years after adjustment for age, education, cognitive performance, and antidepressants use. This study showed that reduced plasma Aβ42/Aβ40 ratio is consistently associated with LLMD diagnosis and that increased severity of depression at baseline predicted low Aβ42/Aβ40 ratio at 3 years. Future studies are needed to confirm these findings and examine if the consistently lower plasma Aβ42/Aβ40 ratio in LLMD reflects increased brain amyloid deposition, as observed in AD subjects, and an increased risk for progressive cognitive decline and AD.

Neuroimmune Crosstalk in Rheumatoid Arthritis

Recent studies have demonstrated that immunological disease progression is closely related to abnormal function of the central nervous system (CNS). Rheumatoid arthritis (RA) is a chronic, inflammatory synovitis-based systemic immune disease of unknown etiology. In addition to joint pathological damage, RA has been linked to neuropsychiatric comorbidities, including depression, schizophrenia, and anxiety, increasing the risk of neurodegenerative diseases in life. Immune cells and their secreted immune factors will stimulate the peripheral and central neuronal systems that regulate innate and adaptive immunity. The understanding of autoimmune diseases has largely advanced insights into the molecular mechanisms of neuroimmune interaction. Here, we review our current understanding of CNS comorbidities and potential physiological mechanisms in patients with RA, with a focus on the complex and diverse regulation of mood and distinct patterns of peripheral immune activation in patients with rheumatoid arthritis. And in our review, we also discussed the role that has been played by peripheral neurons and CNS in terms of neuron mechanisms in RA immune challenges, and the related neuron-immune crosstalk.

The Athlete's Paradox: Adaptable Depression

We proposed that an athlete's depressive symptoms may be different from the general population in etiology if considered from the context of a depressive disorder. By shifting focus from a limited notion of symptoms onto a comprehensive model of depression, the full scope of the phenomenon becomes clearer. This paper investigated the relationship between neurotransmitters and allostatic load to explain the incidence of depression among elite athletes. This literature review extensively analyzed exercise-induced neurohormonal imbalance resulting in depressive states among athletes. The research revealed that 5-HTTLPR polymorphism, brain-derived neurotrophic factor (BDNF), extensive psychological demands, social stigma, and overtraining syndrome (OTS) may all contribute to a unique version of depression. The research revealed that the biological standards of athletes differ from those of non-athletes, to the point that the new model may be useful, thereby introducing the new term "Adaptable Depression (AD)" to the literature. This framework suggests a new direction for future research to precisely measure the neurotransmitter-related brain changes that result in "Adaptable Depression" in athletes and to establish a better understanding of the depressive tipping point.

Association of Depression With Cardiovascular Diseases

Depression has long been associated with cardiovascular morbidity and mortality. We have reviewed the various factors (hormonal, inflammatory, neuroimmune, and behavioral) involved in depression and associated cardiovascular risk factors. Elevation of glucocorticoids due to activation of the hypothalamic-pituitary-adrenal (HPA) axis in chronic stress of depression results in hyperglycemia, causing insulin resistance, which is a risk factor for heart diseases. This increase in glucocorticoids also stimulates the production of pro-inflammatory cytokines interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha. Literature also showed that chronic stress in depression activates platelet receptors resulting in endothelial dysfunction and cardiovascular morbidity. It has been shown by various studies that depressed patients are more prone to unhealthy lifestyles like eating more processed food, physical inactivity, smoking, and alcohol consumption resulting in weight gain and insulin resistance. Further in the literature, we reviewed some genetic factors associated with depression and cardiovascular outcomes. Elevated glucocorticoids reduce brain-derived neurotrophic factor-dependent upregulation of glutamate receptors involved in various neural circuits associated with depression and neural diseases by suppressing microRNA-132 expression. In depressed obese patients, proprotein convertase subtilisin/kexin type 9 (PCSK-9), a regulator of low-density lipoprotein cholesterol, has been shown to be associated with insulin resistance. This review sheds light on the importance of diagnostic, preventive, and treatment strategies in depressed patients to reduce overall cardiovascular morbidity and mortality.

Antioxidant potential of Pediococcus pentosaceus strains from the sow milk bacterial collection in weaned piglets

BACKGROUND

In modern animal husbandry, breeders pay increasing attention to improving sow nutrition during pregnancy and lactation to favor the health of neonates. Sow milk is a main food source for piglets during their first three weeks of life, which is not only a rich repository of essential nutrients and a broad range of bioactive compounds, but also an indispensable source of commensal bacteria. Maternal milk microorganisms are important sources of commensal bacteria for the neonatal gut. Bacteria from maternal milk may confer a health benefit on the host.

METHODS

Sow milk bacteria were isolated using culturomics followed by identification using 16S rRNA gene sequencing. To screen isolates for potential probiotic activity, the functional evaluation was conducted to assess their antagonistic activity against pathogens in vitro and evaluate their resistance against oxidative stress in damaged Drosophila induced by paraquat. In a piglet feeding trial, a total of 54 newborn suckling piglets were chosen from nine sows and randomly assigned to three treatments with different concentrations of a candidate strain. Multiple approaches were carried out to verify its antioxidant function including western blotting, enzyme activity analysis, metabolomics and 16S rRNA gene amplicon sequencing.

RESULTS

The 1240 isolates were screened out from the sow milk microbiota and grouped into 271 bacterial taxa based on a nonredundant set of 16S rRNA gene sequencing. Among 80 Pediococcus isolates, a new Pediococcus pentosaceus strain (SMM914) showed the best performance in inhibition ability against swine pathogens and in a Drosophila model challenged by paraquat. Pretreatment of piglets with SMM914 induced the Nrf2-Keap1 antioxidant signaling pathway and greatly affected the pathways of amino acid metabolism and lipid metabolism in plasma. In the colon, the relative abundance of Lactobacillus was significantly increased in the high dose SMM914 group compared with the control group.

CONCLUSION

P. pentosaceus SMM914 is a promising probiotic conferring antioxidant capacity by activating the Nrf2-Keap1 antioxidant signaling pathway in piglets. Our study provided useful resources for better understanding the relationships between the maternal microbiota and offspring. Video Abstract.

Guts Imbalance Imbalances the Brain: A Review of Gut Microbiota Association With Neurological and Psychiatric Disorders

Over the last 10 years, there has been a growing interest in the relationship between gut microbiota, the brain, and neurologic-associated affections. As multiple preclinical and clinical research studies highlight gut microbiota’s potential to modulate the general state of health state, it goes without saying that gut microbiota plays a significant role in neurogenesis, mental and cognitive development, emotions, and behaviors, and in the progression of neuropsychiatric illnesses. Gut microbiota produces important biologic products that, through the gut-brain axis, are directly connected with the appearance and evolution of neurological and psychiatric disorders such as depression, anxiety, bipolar disorder, autism, schizophrenia, Parkinson’s disease, Alzheimer’s disease, dementia, multiple sclerosis, and epilepsy. This study reviews recent research on the link between gut microbiota and the brain, and microbiome’s role in shaping the development of the most common neurological and psychiatric illnesses. Moreover, special attention is paid to the use of probiotic formulations as a potential non-invasive therapeutic opportunity for prevention and management of neuropsychiatric-associated affections.

Human adaptative behavior to Antarctic conditions: A review of physiological aspects

The Antarctic environment induces adaptive metabolic and neuroendocrine changes associated with survival, as well as increased risks to physical and mental health. Circadian disruption has been observed in Antarctic expeditioners. The main consequences appear in quality of sleep, which can affect physical and cognitive performance. Physiological adaptation to cold is mediated by the norepinephrine and thyroid hormones (T₃ and 3,5-T₂ metabolite). The observed changes in the hypothalamic-pituitary-thyroid (HPT) axis of expeditioners varied according to temperature, photoperiod, time spent in the cold environment and stress level. The decrease in T₃ levels has frequently been associated with mood swings. Psychological and physical stressors cause disturbances in the hypothalamic-pituitary-adrenal (HPA) axis, with consequent maintenance of high cortisol levels, leading to memory impairment, immunosuppression, and cardiometabolic and reproductive disorders. Preventive measures, such as provision of adequate food, well-established eating times, physical activity and even the use of phototherapy, can all help maintain the circadian rhythm. In addition, the use of high-tech clothing and room temperature control in research stations provide greater protection against the effects of intense cold. However, psychological stress requires a more individualized approach based on the crew's sociocultural characteristics, but it can be mitigated by mental healthcare and training in coping strategies. This article is categorized under: Cardiovascular Diseases > Molecular and Cellular Physiology Cardiovascular Diseases > Environmental Factors Metabolic Diseases > Environmental Factors.

Combination of Stem Cells with Chinese Herbs for Secondary Depression in Neurodegenerative Diseases Based on Traditional Chinese Medicine Theories

Depression is a common secondary symptom in neurodegenerative diseases (NDs) caused by the loss of neurons and glial cells. Recent research focuses on stem cell therapy to replace dead nerve cells, but the low efficiency of stem cell differentiation and short survival time are obstacles limiting the therapy's effectiveness. Clinically, patients with different diseases cannot obtain the same effect by using the same cell therapy. However, traditional Chinese medicine (TCM) often uses syndrome differentiation to determine the treatment plan for NDs. Based on TCM syndrome differentiation and treatment, this article summarizes the advantages of Chinese herbal medicine combined with stem cell therapy, mainly for the effects of various herbs on diseases and stem cells, including prolonging the survival time of stem cells, resisting inflammation, and antidepressant-like effects. In particular, it analyzes the unique pathways of the influence of drugs and acupuncture on different therapies, seeking to clarify the scientific TCM system. This review mainly elaborates on the treatment of secondary depression in TCM and the advantages of a herbal combined stem cell therapy in various methods. We believe it can provide a new clinical concept for secondary depression to obtain good clinical effects and reduce the risks borne by patients.

Neuroprotective and Antioxidant Effects of Riparin I in a Model of Depression Induced by Corticosterone in Female Mice

BACKGROUND

Depression is a common, chronic, and often recurrent serious mood disorder. Conventional antidepressants present limitations that stimulate the search for new drugs. Antioxidant and neuroprotective substances are potential antidepressant agents. In this context, riparin I (RIP I) has presented promising results, emerging as a potential source of a new therapeutic drug. In this study, the antidepressant effect of RIP I was evaluated in an animal model of depression induced by corticosterone (CORT). The involvement of neuroprotective and antioxidant mechanisms in the generation of this effect was also assessed.

METHODS

Female mice were submitted to CORT for 21 days and treated with RIP I in the last 7 days. Behavioral and neurochemical analyses were performed.

RESULTS

The administration of RIP I reversed the depressive and psychotic-like behavior, as well as the cognitive impairment caused by CORT, in addition to regulating oxidative stress parameters and BDNF levels in depression-related brain areas.

CONCLUSION

These findings suggest that RIP I can be a strong candidate for drugs in the treatment of depression.

Bidirectional association between physical multimorbidity and subclinical depression in Chinese older adults: Findings from a prospective cohort study

BACKGROUND

Both physical multimorbidity and subclinical depression pose a significant threat to aging population worldwide. The association between these conditions appeared to be in a bidirectional way, however the joint causal relationship yet to be fully understood in elderly Chinese population.

METHODS

A total of 4605 Chinese elders from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2015) were included for the present study. Physical multimorbidity was defined as having two or more self-reported chronic physical conditions. Subclinical depression was defined by ≥ 12 scores assessed using the 10-item Centre for Epidemiological Studies Depression Scale. The bidirectional association between physical multimorbidity and subclinical depression was examined using multivariable logistic regression models, adjusting for covariates.

RESULTS

During study period, 23.99% of participant reported incident episode of subclinical depression and 21.36% reported physical multimorbidity. In fully adjusted model, those with physical multimorbidity were two times more likely to have subclinical depression (OR = 2.05, 95% CI: 1.71-2.46). Besides that, subclinical depression was associated with physical multimorbidity (OR = 1.84, 95% CI: 1.50-2.46), but in slightly less magnitude. Furthermore, the bidirectional association remains statistically significant across different subgroups.

LIMITATIONS

Chronic conditions were all self-reported and we couldn't adjust for all confounders, which may be subject to measurement error.

CONCLUSIONS

Physical multimorbidity and subclinical depression was associated in a bidirectional way in elderly Chinese population, which highlights the necessary of covering a broad spectrum of aspects of clinical management among adults with physical multimorbidity or subclinical depression.

Hypothalamic Functional Connectivity and Apathy in People with Alzheimer's Disease and Cognitively Normal Healthy Controls

BACKGROUND

Earlier studies have described the neural markers of apathy in Alzheimer's disease (AD) and mild cognitive impairment (MCI), but few focused on the motivation circuits. Here, we targeted hypothalamus, a hub of the motivation circuit.

OBJECTIVE

To examine hypothalamic resting state functional connectivity (rsFC) in relation to apathy.

METHODS

We performed whole-brain regression of hypothalamic rsFC against Apathy Evaluation Scale (AES) total score and behavioral, cognitive, and emotional subscores in 29 patients with AD/MCI and 28 healthy controls (HC), controlling for age, sex, education, cognitive status, and depression. We evaluated the results at a corrected threshold and employed path analyses to assess possible interaction between hypothalamic rsFCs, apathy and depression/memory. Finally, we re-examined the findings in a subsample of amyloid-β-verified AD.

RESULTS

AES total score correlated negatively with hypothalamic precuneus (PCu)/posterior cingulate cortex (PCC) and positively with left middle temporal gyrus (MTG) and supramarginal gyrus rsFCs. Behavioral subscore correlated negatively with hypothalamic PCu/PCC and positively with middle frontal gyrus rsFC. Cognitive subscore correlated positively with hypothalamic MTG rsFC. Emotional subscore correlated negatively with hypothalamic calcarine cortex rsFC. In path analyses, hypothalamic-PCu/PCC rsFC negatively modulated apathy and, in turn, depression. The model where hypothalamic MTG rsFC and memory independently modulated apathy also showed a good fit. The findings of diminished hypothalamic-PCu/PCC rsFC in relation to apathy and, in turn, depression were confirmed in amyloid-verified AD.

CONCLUSION

The findings together support a role of altered hypothalamic connectivity in relation to apathy and depression, and modulation of apathy by memory dysfunction.

Insulin-like Growth Factor II Prevents MPP+ and Glucocorticoid Mitochondrial-Oxidative and Neuronal Damage in Dopaminergic Neurons

Stress seems to contribute to Parkinson’s disease (PD) neuropathology, probably by dysregulation of the hypothalamic–pituitary–adrenal axis. Key factors in this pathophysiology are oxidative stress and mitochondrial dysfunction and neuronal glucocorticoid-induced toxicity. The insulin-like growth factor II (IGF-II), a pleiotropic hormone, has shown antioxidant and neuroprotective effects in some neurodegenerative disorders. Our aim was to examine the protective effect of IGF-II on a dopaminergic cellular combined model of PD and mild to moderate stress measuring oxidative stress parameters, mitochondrial and neuronal markers, and signalling pathways. IGF-II counteracts the mitochondrial-oxidative damage produced by the toxic synergistic effect of corticosterone and 1-methyl-4-phenylpyridinium, protecting dopaminergic neurons from death and neurodegeneration. IGF-II promotes PKC activation and nuclear factor (erythroid-derived 2)-like 2 antioxidant response in a glucocorticoid receptor-dependent pathway, preventing oxidative cell damage and maintaining mitochondrial function. Thus, IGF-II is a potential therapeutic tool for treatment and prevention of disease progression in PD patients suffering mild to moderate emotional stress.

Corticotropin Releasing Factor Binding Protein as a Novel Target to Restore Brain Homeostasis: Lessons Learned From Alcohol Use Disorder Research

Stress is well-known to contribute to the development of many psychiatric illnesses including alcohol and substance use disorder (AUD and SUD). The deleterious effects of stress have also been implicated in the acceleration of biological age, and age-related neurodegenerative disease. The physio-pathology of stress is regulated by the corticotropin-releasing factor (CRF) system, the upstream component of the hypothalamic-pituitary-adrenal (HPA) axis. Extensive literature has shown that dysregulation of the CRF neuroendocrine system contributes to escalation of alcohol consumption and, similarly, chronic alcohol consumption contributes to disruption of the stress system. The CRF system also represents the central switchboard for regulating homeostasis, and more recent studies have found that stress and aberrations in the CRF pathway are implicated in accelerated aging and age-related neurodegenerative disease. Corticotropin releasing factor binding protein (CRFBP) is a secreted glycoprotein distributed in peripheral tissues and in specific brain regions. It neutralizes the effects of CRF by sequestering free CRF, but may also possess excitatory function by interacting with CRF receptors. CRFBP’s dual role in influencing CRF bioavailability and CRF receptor signaling has been shown to have a major part in the HPA axis response. Therefore, CRFBP may represent a valuable target to treat stress-related illness, including: development of novel medications to treat AUD and restore homeostasis in the aging brain. This narrative review focuses on molecular mechanisms related to the role of CRFBP in the progression of addictive and psychiatric disorders, biological aging, and age-related neurodegenerative disease. We provide an overview of recent studies investigating modulation of this pathway as a potential therapeutic target for AUD and age-related neurodegenerative disease.

Electroacupuncture Reverses CUMS-Induced Depression-Like Behaviors and LTP Impairment in Hippocampus by Downregulating NR2B and CaMK II Expression

Objective

Depression is a global mental health problem with high disability rate, which brings a huge disease burden to the world. Electroacupuncture (EA) has been shown to be an effective method for the treatment of depression. However, the mechanism underling the antidepressant effect of EA has not been clearly clarified. The change of synaptic plasticity is the focus in the study of antidepressant mechanism. This study will observe the effect of EA on LTP of hippocampal synaptic plasticity and explore its possible mechanism.

Methods

The depression-like behavior rat model was established by chronic unpredictable mild stress (CUMS). EA stimulation (Hegu and Taichong) was used to treat the depressed rats. The depression-like behavior of rats was tested by weight measurement, open field test, depression preference test, and novelty suppressed feeding test. Long-term potentiation (LTP) was recorded at CA1 synapses in hippocampal slices by electrophysiological method. N-methyl-D-aspartate receptor subunit 2B (NR2B) and calmodulin-dependent protein kinase II (CaMK II) protein levels were examined by using western blot.

Results

After the establishment of CUMS-induced depression model, the weight gain rate, sucrose preference rate, line crossing number, and rearing times of rats decreased, and feeding time increased. At the same time, the LTP in hippocampus was impaired, and the expressions of NR2B and CaMK II were upregulated. After EA treatment, the depression-like behavior of rats was improved, the impairment of LTP was reversed, and the expression levels of NR2B and CaMK II protein were downregulated.

Conclusion

EA can ameliorate depression-like behaviors by restoring LTP induction, downregulating NR2B and CaMK II expression in CUMS model rats, which might be part of the mechanism of EA antidepressant.

COVID-19 Associated Suicidal Ideation in Older Adults: Two Case Reports With a Review of the Literature

The COVID-19 pandemic may profoundly harm the mental health and emotional well- being of many older adults. Public health interventions to minimize the spread of the virus have had the unintended consequences of worsening social isolation, financial stress, and unemployment. Results of early research efforts assessing the impact of these interventions on the mental health of older adults have been mixed. Available findings suggest that a subset of community-dwelling older adults have been less negatively impacted than younger adults, while people of color, the poor, residents of nursing homes and other communal living environments, and those living with dementia and their caregivers are more likely to suffer from COVID-related health problems. This manuscript describes two older adults for whom COVID-19 associated stresses caused significant worsening in their psychiatric illnesses, including the emergence of suicidal ideation, summarizes the literature on the impact of interactions between psychosocial stresses and biological factors on the mental health and well-being of older adults, and discusses interventions to help older adults whose mental health has worsened due to COVID-19. Timely and accurate diagnosis, prompt provision of individualized care using both pharmacologic and psychotherapeutic interventions, adoption of new technologies that permit care to be provided safely at a distance and which allow for virtual social interactions, coupled with ongoing advocacy for policy changes that address significant health care disparities and provide older adults continued access to health care and relief from financial hardship, will help older adults remaining as healthy as possible during the pandemic.

Factors associated with anxiety and depression in rheumatoid arthritis patients: a cross-sectional study

BACKGROUND

The management of anxiety and depression symptoms in rheumatoid arthritis (RA) patients is vital. Previous study findings on this topic are conflicting, and the topic remains to be thoroughly investigated. This study aimed to clarify the association of RA disease activity with anxiety and depression symptoms after controlling for physical disability, pain, and medication.

METHODS

We conducted a cross-sectional study of RA patients from the XXX Rheumatoid Arthritis Management Alliance cohort. We assessed patients using the Disease Activity Score (DAS28), Health Assessment Questionnaire Disability Index (HAQ-DI), and Hospital Anxiety and Depression Scale (HADS). Anxiety and depression symptoms were defined by a HADS score ≥ 8. We analyzed the data using multivariable logistic regression analyses.

RESULTS

Of 517 participants, 17.6% had anxiety symptoms and 27.7% had depression symptoms. The multivariable logistic regression analysis demonstrated that DAS28 was not independently associated with anxiety symptoms (odds ratio [OR] [95% confidence interval; CI] 0.93 [0.48-1.78]; p = 0.82) and depression symptoms (OR [95% CI] 1.45 [0.81-2.61]; p = 0.22). However, DAS28 patient global assessment (PtGA) severity was associated with anxiety symptoms (OR [95% CI] 1.15 [1.02-1.29]; p = 0.03) and depression symptoms (OR [95% CI] 1.21 [1.09-1.35]; p < 0.01). Additionally, HAQ-DI scores ≤ 0.5 were associated with anxiety symptoms (OR [95% CI] 3.51 [1.85-6.64]; p < 0.01) and depression symptoms (OR [95% CI] 2.65 [1.56-4.50]; p < 0.01). Patients using steroids were more likely to have depression than those not using steroids (OR [95% CI] 1.66 [1.03-2.67]; p = 0.04).

CONCLUSIONS

No association was found between RA disease activity and anxiety and depression symptoms in the multivariable logistic regression analysis. Patients with high PtGA scores or HAQ-DI scores ≤ 0.5 were more likely to experience anxiety and depression symptoms, irrespective of disease activity remission status. Rather than focusing solely on controlling disease activity, treatment should focus on improving or preserving physical function and the patient's overall sense of well-being.

Comparative Efficacy of Multiple Therapies for the Treatment of Patients With Subthreshold Depression: A Systematic Review and Network Meta-Analysis

Background: Subthreshold depression (SD) is considered to be the precursor stage of major depression, which is correlated with functional impairment and increased suicide rate. Although there are multiple therapies for the treatment of SD, the comparison and efficacy of various methods has yet to be evaluated. This study aimed to evaluate the efficacy of different therapies by performing a Bayesian network meta-analysis.

Methods: We searched eight databases on April 3, 2021. Center for Epidemiologic Studies Depression Scale (CES-D), Beck Depression Inventory scale (BDI), the Patient Health Questionnaire-9 (PHQ-9), and the Kessler Screening Scale for Psychological Distress (K-6) were used as efficacy outcomes. This Bayesian network meta-analysis used a fixed-effects model.

Findings: Twenty-one randomized controlled trials involving 5,048 participants were included in this study. The results suggested that electroacupuncture (MD −12.00, 95% CrI −15.00, −10.00), conventional acupuncture plus wheat-grain moxibustion (MD −9.70, 95% CrI −14.00, −5.30), and the Chinese traditional peripateticism pill plus group counseling (MD −9.00, 95% CrI −11.00, −6.70) had better efficacy than the control group (CG) in improving CES-D. For BDI outcome, bright light therapy (MD −9.70, 95% CrI −13.00, −6.00), behavioral activation program (MD −5.70, 95% CrI −6.10, −5.40), and dim light therapy (MD −6.30, 95% CrI −10.00, −2.20) were better than the CG. Tai chi (MD −3.00, 95% CrI −4.00, −2.00) was better than CG for PHQ-9 outcomes. Telephone-based cognitive behavioral treatment (MD −2.50 95% CrI −2.70, −2.30) was better than the CG for K-6 scores.

Conclusion: Our results suggest that electroacupuncture or bright light therapy appear to be the better choices in the treatment of SD. This study provide new insights into clinical treatment selection and may aid the development of guidelines for the management of SD.

HPA Axis in the Pathomechanism of Depression and Schizophrenia: New Therapeutic Strategies Based on Its Participation

The hypothalamic-pituitary-adrenal (HPA) axis is involved in the pathophysiology of many neuropsychiatric disorders. Increased HPA axis activity can be observed during chronic stress, which plays a key role in the pathophysiology of depression. Overactivity of the HPA axis occurs in major depressive disorder (MDD), leading to cognitive dysfunction and reduced mood. There is also a correlation between the HPA axis activation and gut microbiota, which has a significant impact on the development of MDD. It is believed that the gut microbiota can influence the HPA axis function through the activity of cytokines, prostaglandins, or bacterial antigens of various microbial species. The activity of the HPA axis in schizophrenia varies and depends mainly on the severity of the disease. This review summarizes the involvement of the HPA axis in the pathogenesis of neuropsychiatric disorders, focusing on major depression and schizophrenia, and highlights a possible correlation between these conditions. Although many effective antidepressants are available, a large proportion of patients do not respond to initial treatment. This review also discusses new therapeutic strategies that affect the HPA axis, such as glucocorticoid receptor (GR) antagonists, vasopressin V1B receptor antagonists and non-psychoactive CB1 receptor agonists in depression and/or schizophrenia.

Impact of Glucocorticoid on a Cellular Model of Parkinson's Disease: Oxidative Stress and Mitochondrial Function

Stress seems to contribute to the neuropathology of Parkinson's disease (PD), possibly by dysregulation of the hypothalamic-pituitary-adrenal axis. Oxidative distress and mitochondrial dysfunction are key factors involved in the pathophysiology of PD and neuronal glucocorticoid-induced toxicity. Animal PD models have been generated to study the effects of hormonal stress, but no in vitro model has yet been developed. Our aim was to examine the impact of corticosterone (CORT) administration on a dopaminergic neuronal cell model of PD induced by the neurotoxin MPP⁺, as a new combined PD model based on the marker of endocrine response to stress, CORT, and oxidative-mitochondrial damage. We determined the impact of CORT, MPP⁺ and their co-incubation on reactive oxygen species production (O2^-•), oxidative stress cellular markers (advanced-oxidation protein products and total antioxidant status), mitochondrial function (mitochondrial membrane potential and mitochondrial oxygen consumption rate) and neurodegeneration (Fluoro-Jade staining). Accordingly, the administration of MPP⁺ or CORT individually led to cell damage compared to controls (p < 0.05), as determined by several methods, whereas their co-incubation produced strong cell damage (p < 0.05). The combined model described here could be appropriate for investigating neuropathological hallmarks and for evaluating potential new therapeutic tools for PD patients suffering mild to moderate emotional stress.

Effectiveness of a musical fitness programme for older adults with cognitive impairment in long-term care facilities: A quasi-experimental study

OBJECTIVE

To investigate the effectiveness of a musical fitness programme (MFP) intervention in improving neuropsychiatric symptoms, depression, upper-limb muscle strength and cognition of older adults with cognitive impairment in long-term care (LTC) facilities.

BACKGROUND

Because of population ageing, the number of older adults with cognitive impairment has been increasing. The effectiveness of medications in treating cognitive impairment is limited; therefore, the global trend has been for non-pharmacological treatments. However, intervention studies of MFPs on older LTC residents with cognitive impairment are scant.

DESIGN

This study adopted a quasi-experimental design in accordance with the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) checklist. In total, 84 older adults with cognitive impairment were recruited from seven LTC facilities. The MFP was implemented from July-November 2019.

METHODS

The intervention group received the MFP, which was 50 min per session, twice a week for 12 weeks, whereas the comparison group received usual care. Neuropsychiatric inventory nursing home version, the Cornell scale for depression in dementia Chinese version, 30-s arm curl test and Mini-Mental State Examination were the outcome measures. Data were analysed using Chi-square test, t test and repeated measure analysis of variance.

RESULTS

After the intervention, the scores of neuropsychiatric inventory and the Cornell depression exhibited significant differences over time between two groups (F = 3.6, p = .029; F = 5.96, p = .003, respectively). Nevertheless, 30-s arm curl test and Mini-Mental State Examination demonstrated non-significant between-group differences.

CONCLUSION

The MFP can effectively reduce neuropsychiatric symptoms and depression in older adults with cognitive impairment in LTC facilities. To ensure a more robust evidence base, more research is warranted.

RELEVANCE TO CLINICAL PRACTICE

The MFP is a non-pharmacological treatment that can be implemented to promote psychological well-being among older adults with cognitive impairment in LTC facilities, and to indirectly reduce nursing staff burden. To assist nursing staff in providing this intervention, on-the-job training is needed.

Sexual Dysfunction and its Determinants in Male Patients with Rheumatoid Arthritis

BACKGROUND: Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease affects about 0.5–1% of adults. Sexuality is an integral part of human quality of life and responsible for our individual welfare, study the association between them is highly important as many studies revealed that sexuality is greatly affected in RA patients. AIM: This study aims to determine the possible different risk factors for sexual dysfunction (SD) in RA and to study the magnitude of SD among RA male patients. METHODS: This is a case–control study carried on 60 males – aged between 18–45 years – attending Family Medicine and Rheumatology Clinic in Kasr Alainy, Cairo University, Egypt. Participants were divided into case and control groups, both groups were matched regarding socioeconomic status. All participants were evaluated for sexual function using international index of erectile function (IIEF), psychological state using patient health questionnaire (PHQ9), disease-related disability using health assessment questionnaire, disease severity using disease activity score 28, and serum testosterone level was assessed. RESULTS: There was a statistically significant difference between both groups regarding IIEF (OR o’s SD among patients were 1.66), PHQ9, and serum testosterone (p = 0.005). There was highly statistically significant negative correlation between sexual problems and depression, disease caused disability, RA duration and there was highly statistically significant positive correlation between sexual problems and serum hormonal level. CONCLUSION: Sexual problems are a prominent problem in males who suffer from RA. Sexual function was significant associated with disease activity, depression, quality of life, and with lower levels of total and free testosterone.

Cardinal role of the environment in stress induced changes across life stages and generations

The stress response in rodents and humans is exquisitely dependent on the environmental context. The interactive element of the environment is typically studied by creating laboratory models of stress-induced plasticity manifested in behavior or the underlying neuroendocrine mediators of the behavior. Here, we discuss three representative sets of studies where the role of the environment in mediating stress sensitivity or stress resilience is considered across varying windows of time. Collectively, these studies testify that environmental variation at an earlier time point modifies the relationship between stressor and stress response at a later stage. The metaplastic effects of the environment on the stress response remain possible across various endpoints, including behavior, neuroendocrine regulation, region-specific neural plasticity, and regulation of receptors. The timescale of such variation spans adulthood, across stages of life history and generational boundaries. Thus, environmental variables are powerful determinants of the observed diversity in stress response. The predominant role of the environment suggests that it is possible to promote stress resilience through purposeful modification of the environment.

Treatment response and age of onset as risk indicators for parkinson disease in patients with major depressive disorder: A nationwide longitudinal study

BACKGROUND

Individuals with major depressive disorder (MDD) have a higher risk of developing Parkinson disease (PD). This study investigated whether response to treatment with antidepressants for MDD can determine patients at risk of developing PD later in life.

METHODS

We enrolled 3303 patients with newly-diagnosed MDD and 13,212 controls between 2002 and 2004 using Taiwan's Nationwide Health Insurance Research Database. We stratified patients with MDD according to the number of antidepressant regimens prescribed to them and the age at MDD onset and followed all participants until the end of 2013. During follow-up, we evaluated patients for the possibility of developing PD.

RESULTS

Patients with MDD had a greater likelihood of developing PD than controls. Patients with difficult-to-treat (DTT) MDD had a higher risk of developing PD than the other MDD subgroups (hazard ratio [HR] = 3.44, 95% confidence interval [95% CI]: = 1.99-5.95). When stratified by age (<50, 50-65, >65 years), DTT patients with middle-age or late-onset MDD exhibited elevated risks of developing PD (50-65 years: HR: 7.03, 95% CI: 2.95-16.76; >65 years: HR: 2.89, 95% CI: 1.26-6.65).

DISCUSSION

Patients with MDD and an onset age of >50 years who responded poorly to antidepressant treatment have an associated higher risk of subsequently developing PD. Therefore, when treating patients with MDD, clinicians should provide intensive antidepressant treatment and evaluations for PD so that risk-prevention measures can be implemented upon MDD diagnosis.

Impact of Surgical Status, Loneliness, and Disability on Interleukin 6, C-Reactive Protein, Cortisol, and Estrogen in Females with Symptomatic Type I Chiari Malformation

Chiari malformation type I (CMI) provides an opportunity for examining possible moderators of allostatic load. CMI patients who had (n = 43) and had not (n = 19) undergone decompression surgery completed questionnaires regarding pain, disability, and loneliness, and provided serum samples for IL-6, CRP, estrogen, and free estradiol assays, and saliva samples to assess diurnal cortisol curves. ANOVAs examining surgical status (decompressed versus non-decompressed), loneliness (high vs. low), and disability (high vs. low) as independent variables and biomarker variables as dependent factors found that loneliness was associated with higher levels of cortisol, F(1, 37) = 4.91, p = .04, η²_P = .11, and lower levels of estrogen, F(1, 36) = 7.29, p = .01, η²_P = .17, but only in decompressed patients. Results highlight the possible impact of loneliness on biological stress responses and the need to intervene to reduce loneliness in patients with symptomatic CMI.

Glucocorticoid impairs mitochondrial quality control in neurons

Neurons are particularly vulnerable to mitochondrial dysfunction due to high energy demand and an inability to proliferate. Therefore, dysfunctional mitochondria cause various neuropathologies. Mitochondrial damage induces maintenance pathways to repair or eliminate damaged organelles. This mitochondrial quality control (MQC) system maintains appropriate morphology, localization, and removal/replacement of mitochondria to sustain brain homeostasis and counter progression of neurological disorders. Glucocorticoid release is an essential response to stressors for adaptation; however, it often culminates in maladaptation if neurons are exposed to chronic and severe stress. Long-term exposure to high levels of glucocorticoids induces mitochondrial dysfunction via genomic and nongenomic mechanisms. Glucocorticoids induce abnormal mitochondrial morphology and dysregulate fusion and fission. Moreover, mitochondrial trafficking is arrested by glucocorticoids and dysfunctional mitochondria are subsequently accumulated around the soma. These alterations lead to energy deficiency, particularly for synaptic transmission that requires large amounts of energy. Glucocorticoids also impair mitochondrial clearance by preventing mitophagy of damaged organelle and suppress mitochondrial biogenesis, resulting in the reduced number of healthy mitochondria. Failure to maintain MQC degrades brain function and contributes to neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and Huntington's disease. However, mechanisms of glucocorticoid action on the regulation of MQC during chronic stress conditions are not well understood. The present review discusses pathways involved in the impairment of MQC and the clinical significance of high glucocorticoid blood levels for neurodegenerative diseases.