Sleep and Microbiome in Psychiatric Diseases

Multimedia: multimodal mediation analysis of microbiome data

Mediation analysis has emerged as a versatile tool for answering mechanistic questions in microbiome research because it provides a statistical framework for attributing treatment effects to alternative causal pathways. Using a series of linked regressions, this analysis quantifies how complementary data relate to one another and respond to treatments. Despite these advances, existing software's rigid assumptions often result in users viewing mediation analysis as a black box. We designed the multimedia R package to make advanced mediation analysis techniques accessible, ensuring that statistical components are interpretable and adaptable. The package provides a uniform interface to direct and indirect effect estimation, synthetic null hypothesis testing, bootstrap confidence interval construction, and sensitivity analysis, enabling experimentation with various mediator and outcome models while maintaining a simple overall workflow. The software includes modules for regularized linear, compositional, random forest, hierarchical, and hurdle modeling, making it well-suited to microbiome data. We illustrate the package through two case studies. The first re-analyzes a study of the microbiome and metabolome of Inflammatory Bowel Disease patients, uncovering potential mechanistic interactions between the microbiome and disease-associated metabolites, not found in the original study. The second analyzes new data about the influence of mindfulness practice on the microbiome. The mediation analysis highlights shifts in taxa previously associated with depression that cannot be explained indirectly by diet or sleep behaviors alone. A gallery of examples and further documentation can be found at https://go.wisc.edu/830110.

IMPORTANCE

Microbiome studies routinely gather complementary data to capture different aspects of a microbiome's response to a change, such as the introduction of a therapeutic. Mediation analysis clarifies the extent to which responses occur sequentially via mediators, thereby supporting causal, rather than purely descriptive, interpretation. Multimedia is a modular R package with close ties to the wider microbiome software ecosystem that makes statistically rigorous, flexible mediation analysis easily accessible, setting the stage for precise and causally informed microbiome engineering.

Sleep deprivation-induced shifts in gut microbiota: Implications for neurological disorders

Sleep deprivation is a prevalent issue in contemporary society, with significant ramifications for both physical and mental well-being. Emerging scientific evidence illuminates its intricate interplay with the gut-brain axis, a vital determinant of neurological function. Disruptions in sleep patterns disturb the delicate equilibrium of the gut microbiota, resulting in dysbiosis characterized by alterations in microbial composition and function. This dysbiosis contributes to the exacerbation of neurological disorders such as depression, anxiety, and cognitive decline through multifaceted mechanisms, including heightened neuroinflammation, disturbances in neurotransmitter signalling, and compromised integrity of the gut barrier. In response to these challenges, there is a burgeoning interest in therapeutic interventions aimed at restoring gut microbial balance and alleviating neurological symptoms precipitated by sleep deprivation. Probiotics, dietary modifications, and behavioural strategies represent promising avenues for modulating the gut microbiota and mitigating the adverse effects of sleep disturbances on neurological health. Moreover, the advent of personalized interventions guided by advanced omics technologies holds considerable potential for tailoring treatments to individualized needs and optimizing therapeutic outcomes. Interdisciplinary collaboration and concerted research efforts are imperative for elucidating the underlying mechanisms linking sleep, gut microbiota, and neurological function. Longitudinal studies, translational research endeavours, and advancements in technology are pivotal for unravelling the complex interplay between these intricate systems.

multimedia: Multimodal Mediation Analysis of Microbiome Data

Mediation analysis has emerged as a versatile tool for answering mechanistic questions in microbiome research because it provides a statistical framework for attributing treatment effects to alternative causal pathways. Using a series of linked regressions, this analysis quantifies how complementary data relate to one another and respond to treatments. Despite these advances, existing software's rigid assumptions often result in users viewing mediation analysis as a black box. We designed the multimedia R package to make advanced mediation analysis techniques accessible, ensuring that statistical components are interpretable and adaptable. The package provides a uniform interface to direct and indirect effect estimation, synthetic null hypothesis testing, bootstrap confidence interval construction, and sensitivity analysis, enabling experimentation with various mediator and outcome models while maintaining a simple overall workflow. The software includes modules for regularized linear, compositional, random forest, hierarchical, and hurdle modeling, making it well-suited to microbiome data. We illustrate the package through two case studies. The first re-analyzes a study of the microbiome and metabolome of Inflammatory Bowel Disease patients, uncovering potential mechanistic interactions between the microbiome and disease-associated metabolites, not found in the original study. The second analyzes new data about the influence of mindfulness practice on the microbiome. The mediation analysis highlights shifts in taxa previously associated with depression that cannot be explained indirectly by diet or sleep behaviors alone. A gallery of examples and further documentation can be found at https://go.wisc.edu/830110.

Impact of Food Intake and Sleep Disturbances on Gut Microbiota

Lactobacilli and Bifidobacteria are types of microbiota that live in the gastrointestinal (GI) system, or gut microbiota, and are essential for both human well-being and disease. This review looks at the relationship between the composition of gut microbiota and function and two important lifestyle factors - dietary intake and sleep disorders. The diversity of the gut microbiota and metabolic processes is strongly influenced by food intake. Fiber-rich diets encourage the development of good bacteria that synthesize short-chain fatty acids (SCFA), while diets heavy in fat or sugar can negatively impact the microbial balance. Microbial communities are also impacted by regular meal schedules and probiotic and prebiotic use. Sleep disturbances cause stress reactions that alter gut microbiota and upset circadian rhythms. These include irregular sleep cycles and insomnia. These effects are driven by the immune system and gut-brain axis dysregulation, which affects microbial diversity and plays a role in GI and metabolic illnesses. The significance of comprehensive lifestyle treatments to improve gut health is highlighted by an understanding of these interconnections. It may be possible to modify the composition of gut microbiota and improve general health outcomes through the use of strategies that emphasize balanced meals, consistent eating schedules, and better sleep hygiene.

Lacticaseibacillus rhamnosus GG alleviates sleep deprivation-induced intestinal barrier dysfunction and neuroinflammation in mice

Consuming probiotic products is a solution that people are willing to choose to augment health. As a global health hazard, sleep deprivation (SD) can cause both physical and mental diseases. The present study investigated the protective effects of Lacticaseibacillus rhamnosus GG (LGG), a widely used probiotic, on a SD mouse model. Here, it has been shown that SD induced intestinal damage in mice, while LGG supplementation attenuated disruption of the intestinal barrier and enhanced the antioxidant capacity. Microbiome analysis revealed that SD caused dysbiosis in the gut microbiota, characterized by increased levels of Clostridium XlVa, Alistipes, and Desulfovibrio, as well as decreased levels of Ruminococcus, which were partially ameliorated by LGG. Moreover, SD resulted in elevated pro-inflammatory cytokine concentrations in both the intestine and the brain, while LGG provided protection in both organs. LGG supplementation significantly improved locomotor activity in SD mice. Although heat-killed LGG showed some protective effects in SD mice, its overall efficacy was inferior to that of live LGG. In terms of mechanism, it was found that AG1478, an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, could diminish the protective effects of LGG. In conclusion, LGG demonstrated the ability to alleviate SD-induced intestinal barrier dysfunction through EGFR activation and alleviate neuroinflammation.

Exploring Causal Links Between Gut Microbiota and Geriatric Syndromes: A Two-Sample Mendelian Randomization Analysis

Background: Both observational studies and clinical trials have demonstrated a link between the gut microbiota and the geriatric syndrome. Nevertheless, the exact nature of this relationship, particularly concerning causality, remains elusive. Mendelian randomization (MR) is a method of inference based on genetic variation to assess the causal relationship between an exposure and an outcome. In this study, we conducted a two-sample Mendelian randomization (TSMR) study to fully reveal the potential genetic causal effects of gut microbiota on geriatric syndromes. Methods: This study used data from genome wide association studies (GWAS) to investigate causal relationships between the gut microbiota and geriatric syndromes, including frailty, Parkinson's disease (PD), delirium, insomnia, and depression. The primary causal relationships were evaluated using the inverse-variance weighted method, MR Egger, simple mode, weighted mode and weighted median. To assess the robustness of the results, horizontal pleiotropy was examined through MR-Egger intercept and MR-presso methods. Heterogeneity was assessed using Cochran's Q test, and sensitivity was evaluated via the leave-one-out method. Results: We identified 41 probable causal relationships between gut microbiota and five geriatric syndrome-associated illnesses using the inverse-variance weighted method. Frailty showed five positive and two negative causal relationships, while PD revealed three positive and four negative causal connections. Delirium showed three positive and two negative causal relationships. Similarly, insomnia demonstrated nine positive and two negative causal connections, while depression presented nine positive and two negative causal relationships. Conclusions: Using the TSMR method and data from the public GWAS database and, we observed associations between specific microbiota groups and geriatric syndromes. These findings suggest a potential role of gut microbiota in the development of geriatric syndromes, providing valuable insights for further research into the causal relationship between gut microbiota and these syndromes.

PROVIT-CLOCK: A Potential Influence of Probiotics and Vitamin B7 Add-On Treatment and Metabolites on Clock Gene Expression in Major Depression

INTRODUCTION

An increasing body of evidence suggests a strong relationship between gut health and mental state. Lately, a connection between butyrate-producing bacteria and sleep quality has been discussed. The PROVIT study, as a randomized, double-blind, 4-week, multispecies probiotic intervention study, aims at elucidating the potential interconnection between the gut's metabolome and the molecular clock in individuals with major depressive disorder (MDD).

METHODS

The aim of the PROVIT-CLOCK study was to analyze changes in core clock gene expression during treatment with probiotic intervention versus placebo in fasting blood and the connection with the serum- and stool-metabolome in patients with MDD (n = 53). In addition to clinical assessments in the PROVIT study, metabolomics analyses with 1H nuclear magnetic resonance spectroscopy (stool and serum) and gene expression (RT-qPCR) analysis of the core clock genes ARNTL, PER3, CLOCK, TIMELESS, NR1D1 in peripheral blood mononuclear cells of fasting blood were performed.

RESULTS

The gene expression levels of the clock gene CLOCK were significantly altered only in individuals receiving probiotic add-on treatment. TIMELESS and ARNTL gene expression changed significantly over the 4-week intervention period in both groups. Various positive and negative correlations between metabolites in serum/stool and core clock gene expression levels were observed.

CONCLUSION

Changing the gut microbiome by probiotic treatment potentially influences CLOCK gene expression. The preliminary results of the PROVIT-CLOCK study indicate a possible interconnection between the gut microbiome and circadian rhythm potentially orchestrated by metabolites.

The microbiota-gut-brain-immune interface in the pathogenesis of neuroinflammatory diseases: a narrative review of the emerging literature

Importance

Research is beginning to elucidate the sophisticated mechanisms underlying the microbiota-gut-brain-immune interface, moving from primarily animal models to human studies. Findings support the dynamic relationships between the gut microbiota as an ecosystem (microbiome) within an ecosystem (host) and its intersection with the host immune and nervous systems. Adding this to the effects on epigenetic regulation of gene expression further complicates and strengthens the response. At the heart is inflammation, which manifests in a variety of pathologies including neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Multiple Sclerosis (MS).

Observations

Generally, the research to date is limited and has focused on bacteria, likely due to the simplicity and cost-effectiveness of 16s rRNA sequencing, despite its lower resolution and inability to determine functional ability/alterations. However, this omits all other microbiota including fungi, viruses, and phages, which are emerging as key members of the human microbiome. Much of the research has been done in pre-clinical models and/or in small human studies in more developed parts of the world. The relationships observed are promising but cannot be considered reliable or generalizable at this time. Specifically, causal relationships cannot be determined currently. More research has been done in Alzheimer's disease, followed by Parkinson's disease, and then little in MS. The data for MS is encouraging despite this.

Conclusions and relevance

While the research is still nascent, the microbiota-gut-brain-immune interface may be a missing link, which has hampered our progress on understanding, let alone preventing, managing, or putting into remission neurodegenerative diseases. Relationships must first be established in humans, as animal models have been shown to poorly translate to complex human physiology and environments, especially when investigating the human gut microbiome and its relationships where animal models are often overly simplistic. Only then can robust research be conducted in humans and using mechanistic model systems.

Nutraceutical blends predict enhanced health via microbiota reshaping improving cytokines and life quality: a Brazilian double-blind randomized trial

Nutraceutical interventions supporting microbiota and eliciting clinical improvements in metabolic diseases have grown significantly. Chronic stress, gut dysbiosis, and metainflammation have emerged as key factors intertwined with sleep disorders, consequently exacerbating the decline in quality of life. This study aimed to assess the effects of two nutraceutical formulations containing prebiotics (fructooligosaccharides (FOS), galactooligosaccharides (GOS), yeast β-glucans), minerals (Mg, Se, Zn), and the herbal medicine Silybum marianum L. Gaertn., Asteraceae (Milk thistle or Silymarin). These formulations, namely NSupple (without silymarin) and NSupple_Silybum (with silymarin) were tested over 180 days in overweight/obese volunteers from Brazil's southeastern region. We accessed fecal gut microbiota by partial 16S rRNA sequences; cytokines expression by CBA; anthropometrics, quality of life and sleep, as well as metabolic and hormonal parameters, at baseline (T0) and 180 days (T180) post-supplementation. Results demonstrated gut microbiota reshaping at phyla, genera, and species level post-supplementation. The Bacteroidetes phylum, Bacteroides, and Prevotella genera were positively modulated especially in the NSupple_Silybum group. Gut microbiota modulation was associated with improved sleep patterns, quality-of-life perception, cytokines expression, and anthropometric parameters post-supplementation. Our findings suggest that the nutraceutical blends positively enhance cardiometabolic and inflammatory markers. Particularly, NSupple_Silybum modulated microbiota composition, underscoring its potential significance in ameliorating metabolic dysregulation. Clinical trial registry number: NCT04810572. 23/03/2021.

The influence of maternal diet on offspring's gut microbiota in early life

BACKGROUND

The influence of maternal diet on offspring's health is an area of study that is linked to epigenetics. Maternal diet contributes to determining the health status of offspring and maternally linked mechanisms and is a global health challenge that requires attention. The impact of gut microbiota on host metabolism and offspring health is still not established.

OBJECTIVE

In this review, we intend to discuss the evidence on the impact of maternal diet and the health of offspring gut microbiota. The paper focuses on the gut microbiome of animal models. It captures the maternal diet and its influence on the offspring's gut microbiota, behavior that is supported by cell experimental results. Both inflammation and immune status of offspring induced by maternal diet are discussed. Finally, this review used predicted biological pathways involved in maternal diet and offspring health, and the influence of maternal diet on gut microbiota and offspring behavior. Obesity, diabetes, asthma and allergies, and neurodegenerative disorders and prospects for maternal diet, and microbiota and offspring health were discussed.

CONCLUSION

The review was able to gather that a high-fat diet during pregnancy created a long-lasting metabolic signature on the infant's innate immune system, altering inflammation in the offspring microbiota, which predisposed offspring to obesity and metabolic diseases in adulthood.

Relationships Between Rapid Eye Movement Sleep Behavior Disorder and Parkinson's Disease: Indication from Gut Microbiota Alterations

Rapid eye movement sleep behavior disorder (RBD) has a close relationship with Parkinson's disease (PD) and was even regarded as the most reliable hallmark of prodromal PD. RBD might have similar changes in gut dysbiosis to PD, but the relationship between RBD and PD in gut microbial alterations is rarely studied. In this study, we aim to investigate whether there were consistent changes between RBD and PD in gut microbiota, and found some specific biomarkers in RBD that might indicate phenoconversion to PD. Alpha-diversity showed no remarkable difference and beta-diversity showed significant differences based on the unweighted (R = 0.035, P = 0.037) and weighted (R = 0.0045, P = 0.008) UniFrac analysis among idiopathic RBD (iRBD), PD with RBD, PD without RBD and normal controls (NC). Enterotype distribution indicated iRBD, PD with RBD and PD without RBD were Ruminococcus-dominant while NC were Bacteroides-dominant. 7 genera (4 increased: Aerococcus, Eubacterium, Gordonibacter and Stenotrophomonas, 3 decreased: Butyricicoccus, Faecalibacterium and Haemophilus) were consistently changed in iRBD and PD with RBD. Among them, 4 genera (Aerococcus, Eubacterium, Butyricicoccus, Faecalibacterium) remained distinctive in the comparison between PD with RBD and PD without RBD. Through clinical correlation analysis, Butyricicoccus and Faecalibacterium were found negatively correlated with the severity of RBD (RBD-HK). Functional analysis showed iRBD had similarly increased staurosporine biosynthesis to PD with RBD. Our study indicates that RBD had similar gut microbial changes to PD. Decreased Butyricicoccus and Faecalibacterium might be potential hallmarks of phenoconversion of RBD to PD.

Prevalence of and factors associated with symptoms consistent with a diagnosis of irritable bowel syndrome among resident physicians in standardised training in China: a cross-sectional study

OBJECTIVES

This study aims to investigate the incidence of and factors associated with irritable bowel syndrome (IBS) among resident physicians in standardised training at eight traditional Chinese medicine (TCM) hospitals in China.

DESIGN

A cross-sectional survey was administered to resident physicians in their first to third years of standardised training at eight TCM hospitals.

PARTICIPANTS AND SETTING

A total of 514 resident physicians in standardised training were included.

MEASURES

The questionnaire consisted of two sections, namely: section A collected basic information, and section B included the four-item Perceived Stress Scale (PSS-4), the Patient Health Questionnaire-4 (PHQ-4), the Pittsburgh Sleep Quality Index (PSQI) and the Rome IV criteria for IBS. Univariate and multivariate logistic regression models were constructed to assess the associations of age, sex, body mass index, stress, depression, anxiety, sleep quality and IBS.

RESULTS

Of the included resident doctors, 77.2% were female, 20.4% were obese or underweight and 8.6% had symptoms consistent with a diagnosis of IBS. There were no statistically significant differences in lifestyle factors (night shift work, overtime work or working efficiency during the COVID-19 pandemic) between patients with IBS and participants without IBS (hereafter, non-IBS participants) (p=0.429, p=0.572 or p=0.464, respectively). Notably, compared with non-IBS participants, patients with IBS had significantly higher mean scores on the PSS-4 and PHQ-4 (p=0.028 and p=0.012, respectively); however, there was not a significant difference in PSQI scores between these two groups (p=0.079). Depression symptoms were significantly associated with IBS (unadjusted OR 0.498, 95% CI 0.265 to 0.935, p=0.030).

CONCLUSION

These findings suggest that IBS is common among resident physicians in standardised training. Future studies should investigate emotional distress, especially stress and depression, in the development of prevention or treatment of IBS.

Serum Zonula Occludens-1 and Claudin-5 Levels in Patients with Insomnia Disorder: A Pilot Study

Purpose

This research aimed to investigate serum Zonula occludens-1 (ZO-1) and Claudin-5 (CLDN5) levels to show whether or not their eventual changes in patients with insomnia disorder could have etiopathogenetic importance. There was no research investigating serum ZO-1 and CLDN5 concentrations in insomnia disorder.

Patients and Methods

This study included 60 insomnia disorder patients and 45 normal controls. None of the patients received drugs for insomnia. The patients completed Insomnia Severity Index (ISI) and Pittsburgh Sleep Quality Index (PSQI), and Polysomnography (PSG) to score the insomnia disorder symptoms. Venous blood samples were collected, and serum ZO-1 and claudin-5 levels were analyzed by enzyme-linked immunosorbent assay (ELISA).

Results

Serum ZO-1 level was significantly higher without a significant difference between age, sex, and body mass index, whereas the difference in serum claudin-5 level between the two groups was not statistically significant. In addition, ZO-1 levels were positively correlated with ISI and PSQI and negatively with N1 and N1_perc. We also demonstrated a positive correlation between the levels of CLDN5 and HAMA, and a negative correlation with total sleep time (TST), N1 and N1_perc.

Conclusion

Our findings suggest an association between these intestinal and brain endothelial permeability markers and insomnia disorders. However, these remain modest and preliminary and need more extensive studies, including long-term follow-up populations and involving gut microbes, to further validate and explore the mechanisms involved.

Puerarin alleviates sleep disorders in aged mice related to repairing intestinal mucosal barrier

More and more evidence suggests that puerarin, a potential remedy for gut inflammation, may have an ameliorative effect on sleep disturbances. However, the relationship between puerarin and sleep disruption has not been extensively researched. This study aims to explore the role and mechanisms of puerarin in improving sleep disorders. We established a light-induced sleep disorder model in mice and assessed the effects of puerarin on cognitive behavior using open field and water maze tests. Pathological detection demonstrated that sleep disturbances resulted in observable damage to the liver, lung, and kidney. Puerarin reversed multi-organ damage and inflammation. Further, puerarin activated paneth cells, resulting in increased lysozyme and TGF-β production, and stimulating intestinal stem cell proliferation. Puerarin also effectively inhibited the expression of F4/80, iNOS, TNF-α, and IL-1β in the small intestine, while it increased Chil3, CD206, and Arg-1 levels. Moreover, puerarin treatment significantly decreased P-P65, TLR4, Bcl-xl, and cleaved caspase-3 protein levels while increasing barrier protein levels, including ZO-1, Occludin, Claudin 1 and E-cadherin suggesting a reduction in inflammation and apoptosis in the gut. Overall, puerarin diminished systemic inflammation, particularly intestinal inflammation, and enhanced intestinal barrier integrity in mice with sleep disorders. Our findings suggest a potential new therapeutic pathway for sleep disorders.

The brain-gut-microbiota axis in the treatment of neurologic and psychiatric disorders

The human gut microbiota is a complex ecosystem made of trillions of microorganisms. The composition can be affected by diet, metabolism, age, geography, stress, seasons, temperature, sleep, and medications. The increasing evidence about the existence of a close and bi-directional correlation between the gut microbiota and the brain indicates that intestinal imbalance may play a vital role in the development, function, and disorders of the central nervous system. The mechanisms of interaction between the gut-microbiota on neuronal activity are widely discussed. Several potential pathways are involved with the brain-gut-microbiota axis, including the vagus nerve, endocrine, immune, and biochemical pathways. Gut dysbiosis has been linked to neurological disorders in different ways that involve activation of the hypothalamic-pituitary-adrenal axis, imbalance in neurotransmitter release, systemic inflammation, and increase in the permeability of the intestinal and the blood-brain barrier. Mental and neurological diseases have become more prevalent during the coronavirus disease 2019pandemic and are an essential issue in public health globally. Understanding the importance of diagnosing, preventing, and treating dysbiosis is critical because gut microbial imbalance is a significant risk factor for these disorders. This review summarizes evidence demonstrating the influence of gut dysbiosis on mental and neurological disorders.

Gut Microbiome Composition and Its Association with Sleep in Major Psychiatric Disorders

INTRODUCTION

Sleep disturbances are highly prevalent across most major psychiatric disorders. Alterations in the hypothalamic-pituitary-adrenal axis, neuroimmune mechanisms, and circadian rhythm disturbances partially explain this connection. The gut microbiome is also suspected to play a role in sleep regulation, and recent studies suggest that certain probiotics, prebiotics, synbiotics, and fecal microbiome transplantation can improve sleep quality.

METHODS

We aimed to assess the relationship between gut-microbiota composition, psychiatric disorders, and sleep quality in this cross-sectional, cross-disorder study. We recruited 103 participants, 63 patients with psychiatric disorders (major depressive disorder [n = 31], bipolar disorder [n = 13], psychotic disorder [n = 19]) along with 40 healthy controls. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). The fecal microbiome was analyzed using 16S rRNA sequencing, and groups were compared based on alpha and beta diversity metrics, as well as differentially abundant species and genera.

RESULTS

A transdiagnostic decrease in alpha diversity and differences in beta diversity indices were observed in psychiatric patients, compared to controls. Correlation analysis of diversity metrics and PSQI score showed no significance in the patient and control groups. However, three species, Ellagibacter isourolithinifaciens, Senegalimassilia faecalis, and uncultured Blautia sp., and two genera, Senegalimassilia and uncultured Muribaculaceae genus, were differentially abundant in psychiatric patients with good sleep quality (PSQI >8), compared to poor-sleep quality patients (PSQI ≤8).

CONCLUSION

In conclusion, this study raises important questions about the interconnection of the gut microbiome and sleep disturbances.

Altered gut microbiota profile in patients with perimenopausal panic disorder

Introduction

Females in the perimenopausal period are susceptible to mood disorders. Perimenopausal panic disorder (PPD) is characterized by repeated and unpredictable panic attacks during perimenopause, and it impacts the patient's physical and mental health and social function. Pharmacotherapy is limited in the clinic, and its pathological mechanism is unclear. Recent studies have demonstrated that gut microbiota is strongly linked to emotion; however, the relation between PPD and microbiota is limitedly known.

Methods

This study aimed to discover specific microbiota in PPD patients and the intrinsic connection between them. Gut microbiota was analyzed in PPD patients (n = 40) and healthy controls (n = 40) by 16S rRNA sequencing.

Results

The results showed reduced α-diversity (richness) in the gut microbiota of PPD patients. β-diversity indicated that PPD and healthy controls had different intestinal microbiota compositions. At the genus level, 30 species of microbiota abundance had significantly different between the PPD and healthy controls. In addition, HAMA, PDSS, and PASS scales were collected in two groups. It was found that Bacteroides and Alistipes were positively correlated with PASS, PDSS, and HAMA.

Discussion

Bacteroides and Alistipes dysbiosis dominate imbalanced microbiota in PPD patients. This microbial alteration may be a potential pathogenesis and physio-pathological feature of PPD. The distinct gut microbiota can be a potential diagnostic marker and a new therapeutic target for PPD.

The Role of the Gut Microbiome in Bipolar Disorder and its Common Comorbidities

Bipolar disorder is a decidedly heterogeneous and multifactorial disease, with significant psychosocial and medical disease burden. Much difficulty has been encountered in developing novel therapeutics and objective biomarkers for clinical use in this population. In that regard, gut-microbial homeostasis appears to modulate several key pathways relevant to a variety of psychiatric, metabolic, and inflammatory disorders. Microbial impact on immune, endocrine, endocannabinoid, kynurenine, and other pathways are discussed throughout this review. Emphasis is placed on this system's relevance to current pharmacology, diet, and comorbid illness in bipolar disorder. Despite the high level of optimism promoted in many reviews on this topic, substantial obstacles exist before any microbiome-related findings can provide meaningful clinical utility. Beyond a comprehensive overview of pathophysiology, this review hopes to highlight several key areas where progress is needed. As well, novel microbiome-associated suggestions are presented for future research.

Neuropsychiatric sequelae after liver transplantation and their possible mechanism via the microbiota-gut-liver-brain axis

Patients after liver transplantation are often impacted by mental and even neuropsychiatric disorders, including depression, sleep disorders, anxiety, and post-traumatic stress disorder. Neuropsychiatric sequelae have an adverse impact on rehabilitation and can even incapacitate people, reducing their quality of life. Despite screening tools and effective treatments, neuropsychiatric sequelae after liver transplantation (NSALT) have not been fully diagnosed and treated. Current research suggests that NSALT may be partly related to intestinal microbial variation, but the detailed mechanism remains unclear. In this review, we describe the clinical and diagnostic features, prevalence, prediction, clinical course and outcome, management, and treatment of NSALT; we also summarize their mechanisms through the microbiota-gut-liver-brain axis. Finally, we propose to improve NSALT on the basis of adjusting the gastrointestinal flora, immune inflammation or vagus nerve (VN), providing a novel strategy for clinical prevention and treatment.

Complementary and Integrative Approaches to Sleep Disorders in Children

Sleep problems are very common in children and adolescents. Chronic insomnia is the leading cause of sleep disorders in children and adolescents. Adjunctive interventions that address low ferritin levels and vitamin D3 deficiency are helpful in children and adolescents. The addition of l-5-hydroxytryptophan, gabadone, l-theanine, Ashwagandha, omega 3 fatty acids, probiotics in bipolar disorder, and children with colic, meditation, and changing from a high-fat diet to a Mediterranean diet are also helpful adjunctive interventions. Actigraphy data should be collected in future sleep studies because subjective data may not indicate the true effect of the intervention.

New Perspectives on Sleep Regulation by Tea: Harmonizing Pathological Sleep and Energy Balance under Stress

Sleep, a conservative evolutionary behavior of organisms to adapt to changes in the external environment, is divided into natural sleep, in a healthy state, and sickness sleep, which occurs in stressful environments or during illness. Sickness sleep plays an important role in maintaining energy homeostasis under an injury and promoting physical recovery. Tea, a popular phytochemical-rich beverage, has multiple health benefits, including lowering stress and regulating energy metabolism and natural sleep. However, the role of tea in regulating sickness sleep has received little attention. The mechanism underlying tea regulation of sickness sleep and its association with the maintenance of energy homeostasis in injured organisms remains to be elucidated. This review examines the current research on the effect of tea on sleep regulation, focusing on the function of tea in modulating energy homeostasis through sickness sleep, energy metabolism, and damage repair in model organisms. The potential mechanisms underlying tea in regulating sickness sleep are further suggested. Based on the biohomology of sleep regulation, this review provides novel insights into the role of tea in sleep regulation and a new perspective on the potential role of tea in restoring homeostasis from diseases.

Gut microbiota is associated with the effect of photoperiod on seasonal breeding in male Brandt's voles (Lasiopodomys brandtii)

BACKGROUND

Seasonal breeding in mammals has been widely recognized to be regulated by photoperiod, but the association of gut microbiota with photoperiodic regulation of seasonal breeding has never been investigated.

RESULTS

In this study, we investigated the association of gut microbiota with photoperiod-induced reproduction in male Brandt's voles (Lasiopodomys brandtii) through a long-day and short-day photoperiod manipulation experiment and fecal microbiota transplantation (FMT) experiment. We found photoperiod significantly altered reproductive hormone and gene expression levels, and gut microbiota of voles. Specific gut microbes were significantly associated with the reproductive hormones and genes of voles during photoperiod acclimation. Transplantation of gut microbes into recipient voles induced similar changes in three hormones (melatonin, follicle-stimulating hormone, and luteinizing hormone) and three genes (hypothalamic Kiss-1, testicular Dio3, and Dio2/Dio3 ratio) to those in long-day and short-day photoperiod donor voles and altered circadian rhythm peaks of recipient voles.

CONCLUSIONS

Our study firstly revealed the association of gut microbiota with photoperiodic regulation of seasonal breeding through the HPG axis, melatonin, and Kisspeptin/GPR54 system. Our results may have significant implications for pest control, livestock animal breeding, and human health management. Video Abstract.

Multiomics Analysis Reveals Aberrant Metabolism and Immunity Linked Gut Microbiota with Insomnia

Studies have confirmed that insomnia is related to gut microbiota. Previous research suggests that immunity and metabolism are also associated with insomnia. However, to our knowledge, the integration of these factors has not been investigated in insomnia. Here, we explored the correlations across gut microbiota, serum metabolism, and inflammatory factors in insomnia. Our results showed that the composition and structure of gut microbiota and metabolism in insomnia patients were different from healthy controls. Compared to healthy controls, the relative abundances of Lactobacillus, Streptococcus, and Lactobacillus crispatus were significantly increased in insomniacs. There were five metabolic pathways in insomniacs (glycerophospholipid metabolism; glutathione metabolism; nitrogen metabolism; alanine, aspartate, and glutamate metabolism; aminoacyl-tRNA biosynthesis) significantly different between the two groups. Moreover, we found that IL-1β levels were significantly higher in insomnia patients while TNF-α was significantly reduced. We further identified that the changes in the level of IL-1β and TNF-α were associated with some specific bacteria and metabolites, such as Prevotella amnii, Prevotella buccalis, Prevotella timonensis, and Prevotella colorans. Mediation analysis further determined that the immune factors and metabolites could mediate the relationship between gut microbes and insomnia. IMPORTANCE Our study indicated that systematic inflammation and metabolites might be a pathway linking the gut microbiome with insomnia. These findings provide new insights and a better understanding of gut microbiota's role in insomnia as well as potential novel microbiome-related etiologies for insomnia.

Intervention Effects of Okra Extract on Brain-Gut Peptides and Intestinal Microorganisms in Sleep Deprivation Rats

Objective

Okra, possessing various bioactive components, is used to treat different diseases. This study sought to estimate the intervention effects of okra extract (OE) on brain-gut peptides (BGPs) and intestinal microorganisms in sleep deprivation (SD) rats.

Methods

SD rat models were established using the modified multiple platform method and then treated with normal saline, diazepam tablets, or different doses of OE. Body weight and average daily water consumption of rats were recorded. Depressive behaviors of rats were assessed by the open field test and sucrose preference test. Serum levels of noradrenaline, melatonin, inflammatory factors (IL-1β/IL-6/TNF-α/IL-4/IL-10), and BGP indexes, including gastrin (GAS), motilin (MTL), 5-hydroxytryptamine (5-HT), cholecystokinin (CCK), and vasoactive intestinal peptide (VIP) were measured by ELISA. Additionally, the DNA relative contents of representative intestinal microorganisms in the collected rat feces were determined using RT-qPCR.

Results

SD decreased body weight and average daily water consumption and induced depressive behaviors as well as stress and inflammatory responses in rats. SD rats exhibited lowered GAS, MTL, 5-HT, and VIP but elevated CCK and showed diminished DNA relative contents of Bacteroidetes and probiotics (Bifidobacteria and Lactobacilli) but increased Clostridium perfringens. OE at different doses ameliorated the depressive behaviors and mitigated the stress and inflammatory responses in SD rats, raised the serum contents of GAS, MTL, 5-HT, and VIP, reduced CCK level, elevated the DNA relative contents of Bacteroidetes and probiotics, but diminished Clostridium perfringens. OE exhibited similar intervention effects to diazepam tablets (positive control).

Conclusion

OE exerts intervention effects on BGPs and intestinal microorganisms in SD rats.

The PROVIT Study-Effects of Multispecies Probiotic Add-on Treatment on Metabolomics in Major Depressive Disorder-A Randomized, Placebo-Controlled Trial

The gut-brain axis plays a role in major depressive disorder (MDD). Gut-bacterial metabolites are suspected to reduce low-grade inflammation and influence brain function. Nevertheless, randomized, placebo-controlled probiotic intervention studies investigating metabolomic changes in patients with MDD are scarce. The PROVIT study (registered at clinicaltrials.com NCT03300440) aims to close this scientific gap. PROVIT was conducted as a randomized, single-center, double-blind, placebo-controlled multispecies probiotic intervention study in individuals with MDD (n = 57). In addition to clinical assessments, metabolomics analyses (1H Nuclear Magnetic Resonance Spectroscopy) of stool and serum, and microbiome analyses (16S rRNA sequencing) were performed. After 4 weeks of probiotic add-on therapy, no significant changes in serum samples were observed, whereas the probiotic groups' (n = 28) stool metabolome shifted towards significantly higher concentrations of butyrate, alanine, valine, isoleucine, sarcosine, methylamine, and lysine. Gallic acid was significantly decreased in the probiotic group. In contrast, and as expected, no significant changes resulted in the stool metabolome of the placebo group. Strong correlations between bacterial species and significantly altered stool metabolites were obtained. In summary, the treatment with multispecies probiotics affects the stool metabolomic profile in patients with MDD, which sets the foundation for further elucidation of the mechanistic impact of probiotics on depression.

Effects of vaccination, new SARS-CoV-2 variants and reinfections on post-COVID-19 complications

Post-COVID-19 complications involve a variety of long-lasting health complications emerging in various body systems. Since the prevalence of post-COVID-19 complications ranges from 8-47% in COVID-19 survivors, it represents a formidable challenge to COVID-19 survivors and the health care system. Post-COVID-19 complications have already been studied in the connection to risk factors linked to their higher probability of occurrence and higher severity, potential mechanisms underlying the pathogenesis of post-COVID-19 complications, and their functional and structural correlates. Vaccination status has been recently revealed to represent efficient prevention from long-term and severe post-COVID-19 complications. However, the exact mechanisms responsible for vaccine-induced protection against severe and long-lasting post-COVID-19 complications remain elusive. Also, to the best of our knowledge, the effects of new SARS-CoV-2 variants and SARS-CoV-2 reinfections on post-COVID-19 complications and their underlying pathogenesis remain to be investigated. This hypothesis article will be dedicated to the potential effects of vaccination status, SARS-CoV-2 reinfections, and new SARS-CoV-2 variants on post-COVID-19 complications and their underlying mechanisms Also, potential prevention strategies against post-COVID complications will be discussed.

Drugs, Guts, Brains, but Not Rock and Roll: The Need to Consider the Role of Gut Microbiota in Contemporary Mental Health and Wellness of Emerging Adults

Emerging adulthood (ages 18-25) is a critical period for neurobiological development and the maturation of the hypothalamic-pituitary-adrenal axis. Recent findings also suggest that a natural perturbation of the gut microbiota (GM), combined with other factors, may create a unique vulnerability during this period of life. The GM of emerging adults is thought to be simpler, less diverse, and more unstable than either younger or older people. We postulate that this plasticity in the GM suggests a role in the rising mental health issues seen in westernized societies today via the gut-brain-microbiota axis. Studies have paid particular attention to the diversity of the microbiota, the specific function and abundance of bacteria, and the production of metabolites. In this narrative review, we focus specifically on diet, physical activity/exercise, substance use, and sleep in the context of the emerging adult. We propose that this is a crucial period for establishing a stable and more resilient microbiome for optimal health into adulthood. Recommendations will be made about future research into possible behavioral adjustments that may be beneficial to endorse during this critical period to reduce the probability of a "dysbiotic" GM and the emergence and severity of mental health concerns.

Gut Microbial Dysbiosis and Cognitive Impairment in Bipolar Disorder: Current Evidence

Recent studies have reported that the gut microbiota influences mood and cognitive function through the gut-brain axis, which is involved in the pathophysiology of neurocognitive and mental disorders, including Parkinson’s disease, Alzheimer’s disease, and schizophrenia. These disorders have similar pathophysiology to that of cognitive dysfunction in bipolar disorder (BD), including neuroinflammation and dysregulation of various neurotransmitters (i.e., serotonin and dopamine). There is also emerging evidence of alterations in the gut microbial composition of patients with BD, suggesting that gut microbial dysbiosis contributes to disease progression and cognitive impairment in BD. Therefore, microbiota-centered treatment might be an effective adjuvant therapy for BD-related cognitive impairment. Given that studies focusing on connections between the gut microbiota and BD-related cognitive impairment are lagging behind those on other neurocognitive disorders, this review sought to explore the potential mechanisms of how gut microbial dysbiosis affects cognitive function in BD and identify potential microbiota-centered treatment.

Gut microbiome and daytime function in Chinese patients with major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is underscored by daytime dysfunction-associated features, including mood disturbances, impaired cognition, fatigue, and daytime sleepiness. Importantly, the gut-brain axis may represent a potential mechanistic link between MDD and daytime dysfunction. Therefore, this study aimed to explore the gut microbiome composition and daytime dysfunction in Chinese patients with MDD.

METHODS

We enrolled 36 patients with MDD and 45 healthy controls (HCs) matched by age, sex, and body mass index (BMI). Daytime function including emotion, fatigue, and sleepiness were assessed using the Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD). 16S rRNA sequencing was employed to characterize the gut microbiota in stool samples.

RESULTS

The operational taxonomic units (OTUs) OTU255, OUT363 were positively correlated with HAMD and HAMA. OTU244, OTU542 and OTU221 were positively correlated with ESS, HAMD and HAMA. OTU725 and OTU80 were positively correlated with FSS, ESS, HAMD and HAMA, while OTU423 and OTU502 were negatively correlated with all above. Flavonifractor positively correlated with fatigue in patients with MDD and all individuals simultaneously. The correlation between gut microbiome and daytime function was different in MDD and HCs.

CONCLUSIONS

We identified several OTUs associated with the severity of fatigue, depression, daytime sleepiness and anxiety in all individuals. Our results revealed the differences in microbiome found between patients with MDD and HCs. These findings provide insights into the potential microbiota changes that occur in MDD, and will enable the development of specific therapeutic strategies for targeting the various symptoms of depression.

New sources of lactic acid bacteria with potential antibacterial properties

In the face of the growing demand for functional food, the search for new sources of lactic acid bacteria (LAB) becomes a priority. In our research, we used multiplied culture conditions followed by identification via the matrix-assisted laser desorption ionization-time of flight mass spectrometry for seeking LAB strains in plant- and animal-derived sources. Furthermore, the selected LAB isolates were examined for their proteolytic activity as well as antimicrobial action against different bacterial pathogens. The applied method appeared to be useful tool for searching LAB strains within different types of the biological matrices. The best source of the LABs was from calf. Comparing properties of the two selected LABs, those isolated from calf demonstrated the greatest proteolytic and antibacterial properties suggesting that gastrointestinal microbiota are the most valuable LAB source. Nevertheless, second selected strain derived from pickled cucumber juice may be also treated as a promising source of potential probiotic strains.

Altered gut microbiota correlates with cognitive impairment in Chinese children with Down's syndrome

Down's syndrome (DS), a common chromosomal disease caused by chromosome 21 trisomy, is the main cause of cognitive impairment in children worldwide. Emerging evidence suggests that the microbiota-gut-brain axis plays a potential role in cognitive impairment. However, data regarding gut microbiota alterations in DS patients remain scarce, especially data from children with DS. This case-control study was conducted to explore the gut microbiota composition in Chinese DS children. Additionally, the potential association between gut microbiota and cognitive function in DS was evaluated. Microbiota communities in the feces of 15 DS subjects and 15 matched controls were investigated using high-throughput Illumina Miseq sequencing targeting the V3-V4 region of 16S rRNA gene. The relationships between gut microbiota composition and DS cognitive function scores were analyzed. The structure and richness of the gut microbiota differed between DS patients and healthy controls. The abundance of Acidaminococcaceae was decreased in DS patients. Moreover, the Kyoto Encyclopedia of Genes and Genomes analysis showed increased modules related to peptidases and pyrimidine metabolism. Overall, we confirmed that gut microbiota alterations occurred in Chinese patients with DS. Additionally, the fecal microbiota was closely related to DS cognitive impairment. Larger cohorts are needed to confirm these findings and to clarify the mechanisms involved. Elucidating these novel findings in the field of microbiota-gut-brain axis will provide a promising strategy for future studies of DS cognitive impairment.

Synchronizing Our Clocks as We Age: The Influence of the Brain-Gut-Immune Axis on the Sleep-Wake Cycle Across the Lifespan

The microbes that colonize the small and large intestines, known as the gut microbiome, play an integral role in optimal brain development and function. The gut microbiome is a vital component of the bi-directional communication pathway between the brain, immune system, and gut, also known as the brain-gut-immune axis. To date there has been minimal investigation into the implications of improper development of the gut microbiome and the brain-gut-immune axis on the sleep-wake cycle, particularly during sensitive periods of physical and neurological development, such as childhood, adolescence, and senescence. Therefore, this review will explore the current literature surrounding the overlapping developmental periods of the gut microbiome, brain, and immune system from birth through to senescence, while highlighting how the brain-gut-immune axis affects maturation and organisation of the sleep-wake cycle. We also examine how dysfunction to either the microbiome or the sleep-wake cycle negatively affects the bidirectional relationship between the brain and gut, and subsequently the overall health and functionality of this complex system. Additionally, this review integrates therapeutic studies to demonstrate when dietary manipulations, such as supplementation with probiotics and prebiotics, can modulate the gut microbiome to enhance health of the brain-gut-immune axis and optimize our sleep-wake cycle.

Comprehensive 16S rDNA Sequencing and LC-MS/MS-Based Metabolomics to Investigate Intestinal Flora and Metabolic Profiles of the Serum, Hypothalamus and Hippocampus in p‑Chlorophenylalanine-Induced Insomnia Rats Treated with Lilium brownie

Gut microbiota homeostasis in the organism and insomnia have been reported to influence each other. In the study, a method of 16S rRNA gene sequencing combined with ultra-high performance liquid chromatography-mass/mass spectrometry was adopted to evaluate the effects of Lilium brownie (LB) on intestinal flora and metabolic profiles of serum, hypothalamus and hippocampus in insomnia rat induced by p‑chlorophenylalanine (PCPA). It was observed that the imbalance in the diversity and abundance of gut microbiota induced by PCPA was restored after LB intervention. Among these, the Porphyromonadaceae, Lactobacillus and Escherichia were significantly adjusted at the genus level by PCPA and LB, respectively. It was also found that the most of metabolic phenotypes in serum, hypothalamus and hippocampus perturbed by PCPA were regulated towards normal after LB intervention, especially 5-hydroxy-L-tryptophan of the hypothalamus involving in 5-HT metabolism. Moreover, the arachidonic acid metabolism in serum, hypothalamus and hippocampus, and the serotonergic synapse in hypothalamus and hippocampus were the most fundamentally and significantly affected pathways after LB intervention. The results of correlation analysis showed that several floras including Pseudoruegeria have an outstanding contribution to the change of differential metabolites. In brief, the results confirm that gut microbiota is significantly returned to normal and may interact with the corresponding metabolites to relieve insomnia under LB intervention.

COVID-19-related fears and information frequency predict sleep behavior in bipolar disorder

INTRODUCTION

The coronavirus disease (COVID-19) pandemic and consequent restrictions including social distancing had a great impact on everyday life. To date, little is known about how the restrictions affected sleep, which is commonly disturbed in bipolar disorder (BD). The aim of this study was to elucidate sleep patterns during the pandemic in Austrian BD individuals.

METHODS

An online survey assessed sleep with the Pittsburgh Sleep Quality Index (PSQI) and COVID-19-associated attitudes, fears, and emotional distress of 20 BD individuals and 19 controls (HC) during the pandemic. The survey was conducted in April 2020, when very strict regulations were declared, and repeated in May, when they were loosened.

RESULTS

Individuals with BD reported overall poor sleep according to PSQI sum at both time points. Subjective sleep quality, sleep latency, daytime sleepiness, and PSQI sum were worse in individuals with BD than in HC. Individuals with BD informed themselves more frequently about pandemic-related topics. Higher information frequency and more COVID-19 fears (about the virus, own infection, contracting others) correlated with worse PSQI values. Regression models found in BD group that higher information frequency as well as higher COVID-19 fears in April predicted worse sleep characteristics in May, in particular subjective sleep quality, sleep duration, sleep efficiency, and daytime sleepiness.

CONCLUSION

As sufficient sleep duration and quality are essential for well-being and particularly important for vulnerable BD individuals, it is important that information about the pandemic is gathered to a reasonable extent and mental health professionals include COVID-19-related fears when currently treating BD.

Insomnia disorder and its reciprocal relation with psychopathology

Sleep is crucial for daytime functioning. In populations with psychiatric conditions, many people suffer from insomnia symptoms or an insomnia disorder. Emerging evidence suggests a bidirectional relationship between insomnia and various psychopathologies, implying that insomnia not only may be a consequence of mental disorders but also may contribute to new development, symptom severity, and reoccurrence of diverse mental disorders. Research on potential mechanisms underlying the insomnia psychopathology association is important, both from the preventive and treatment perspective. Most hypotheses concern the influence of insomnia on emotion regulation and on shared pathophysiological pathways, ranging from gut microbiome composition to genetic and specific neurotransmitter system aberrations.