Effect of Lactobacillus rhamnosus HN001 in Pregnancy on Postpartum Symptoms of Depression and Anxiety: A Randomised Double-blind Placebo-controlled Trial

The Putative Antidepressant Mechanisms of Probiotic Bacteria: Relevant Genes and Proteins

Probiotic bacteria are widely accepted as therapeutic agents against inflammatory bowel diseases for their immunostimulating effects. In the last decade, more evidence has emerged supporting the positive effects of probiotics on the course of neurodegenerative and psychiatric diseases. This brief review summarizes the data from clinical studies of probiotics possessing antidepressant properties and focuses on the potential genes and proteins underlying these mechanisms. Data from small-sample placebo-controlled pilot studies indicate that certain strains of bacteria can significantly reduce the symptoms of depression, especially in depressed patients. Despite the disparity between studies attempting to pinpoint the bacterial putative genes and proteins accounting for these mechanisms, they ultimately show that bacteria are a potential source of metabiotics—microbial metabolites or structural components. Since the constituents of cells—namely, secreted proteins, peptides and cell wall components—are most likely to be entangled in the gut–brain axis, they can serve as starting point in the search for probiotics with concrete properties.

Gut microbiota in mental health and depression: role of pre/pro/synbiotics in their modulation

The microbiome residing in the human gut performs a wide range of biological functions. Recently, it has been elucidated that a change in dietary habits is associated with alteration in the gut microflora which results in increased health risks and vulnerability towards various diseases. Falling in line with the same concept, depression has also been shown to increase its prevalence around the globe, especially in the western world. Various research studies have suggested that changes in the gut microbiome profile further result in decreased tolerance of stress. Although currently available medications help in relieving the symptoms of depressive disorders briefly, these drugs are not able to completely reverse the multifactorial pathology of depression. The discovery of the communication pathway between gut microbes and the brain, i.e. the Gut-Brain Axis, has led to new areas of research to find more effective and safer alternatives to current antidepressants. The use of probiotics and prebiotics has been suggested as being effective in various preclinical studies and clinical trials for depression. Therefore, in the present review, we address the new antidepressant mechanisms via gut microbe alterations and provide insight into how these can provide an alternative to antidepressant therapy without the side effects and risk of adverse drug reactions.

Universal and Selective Interventions to Prevent Poor Mental Health Outcomes in Young People: Systematic Review and Meta-analysis

BACKGROUND

Much is not known about the efficacy of interventions to prevent poor mental health outcomes in young people by targeting either the general population (universal prevention) or asymptomatic individuals with high risk of developing a mental disorder (selective prevention).

METHODS

We conducted a PRISMA/MOOSE-compliant systematic review and meta-analysis of Web of Science to identify studies comparing post-test efficacy (effect size [ES]; Hedges' g) of universal or selective interventions for poor mental health outcomes versus control groups, in samples with mean age <35 years (PROSPERO: CRD42018102143). Measurements included random-effects models, I2 statistics, publication bias, meta-regression, sensitivity analyses, quality assessments, number needed to treat, and population impact number.

RESULTS

295 articles (447,206 individuals; mean age = 15.4) appraising 17 poor mental health outcomes were included. Compared to control conditions, universal and selective interventions improved (in descending magnitude order) interpersonal violence, general psychological distress, alcohol use, anxiety features, affective symptoms, other emotional and behavioral problems, consequences of alcohol use, posttraumatic stress disorder features, conduct problems, tobacco use, externalizing behaviors, attention-deficit/hyperactivity disorder features, and cannabis use, but not eating-related problems, impaired functioning, internalizing behavior, or sleep-related problems. Psychoeducation had the highest effect size for ADHD features, affective symptoms, and interpersonal violence. Psychotherapy had the highest effect size for anxiety features.

CONCLUSION

Universal and selective preventive interventions for young individuals are feasible and can improve poor mental health outcomes.

Gut microbiota-derived vitamins - underrated powers of a multipotent ally in psychiatric health and disease

Despite the well-established roles of B-vitamins and their deficiencies in health and disease, there is growing evidence indicating a key role of those nutrients in functions of the central nervous system and in psychopathology. Clinical data indicate the substantial role of B-vitamins in various psychiatric disorders, including major depression, bipolar disorder, schizophrenia, autism, and dementia, including Alzheimer's and Parkinson's diseases. As enzymatic cofactors, B-vitamins are involved in many physiological processes such as the metabolism of glucose, fatty acids and amino acids, metabolism of tryptophan in the kynurenine pathway, homocysteine metabolism, synthesis and metabolism of various neurotransmitters and neurohormones including serotonin, dopamine, adrenaline, acetylcholine, GABA, glutamate, D-serine, glycine, histamine and melatonin. Those vitamins are highly involved in brain energetic metabolism and respiration at the cellular level. They have a broad range of anti-inflammatory, immunomodulatory, antioxidant and neuroprotective properties. Furthermore, some of those vitamins are involved in the regulation of permeability of the intestinal and blood-brain barriers. Despite the fact that a substantial amount of the above vitamins is acquired from various dietary sources, deficiencies are not uncommon, and it is estimated that micronutrient deficiencies affect about two billion people worldwide. The majority of gut-resident microbes and the broad range of bacteria available in fermented food, express genetic machinery enabling the synthesis and metabolism of B-vitamins and, consequently, intestinal microbiota and fermented food rich in probiotic bacteria are essential sources of B-vitamins for humans. All in all, there is growing evidence that intestinal bacteria-derived vitamins play a significant role in physiology and that dysregulation of the "microbiota-vitamins frontier" is related to various disorders. In this review, we will discuss the role of vitamins in mental health and explore the perspectives and potential of how gut microbiota-derived vitamins could contribute to mental health and psychiatric treatment.

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

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

Probiotic Supplement Preparation Relieves Test Anxiety by Regulating Intestinal Microbiota in College Students

Test anxiety creates barriers to learning and performance, which further affects students' social, behavioural, and emotional development. Currently, the medication to treat test anxiety has not been reported yet. Here, we enrolled 120 students to evaluate the effect of probiotic supplement preparation (PSP) on test anxiety from the aspect of the intestinal microbiota. We found that the intake of PSP alleviated the symptoms of depression and anxiety in students with test anxiety by evaluating their mental state using the Hamilton Depression Rating Scale and Hamilton Anxiety Scale. High-throughput sequencing results indicated that the consumption of PSP increased the abundance of Streptococcus and Akkermansia that was lowered by the anxiety state in the intestinal microbiota of students. Meanwhile, taking PSP reduced the level of intestinal pathogens of Fusobacterium and Clostridium as well. In conclusion, our work shows that PSP can reduce test anxiety and restore the disturbed microbiota to the standard level in Chinese college students, rendering the use of PSP a promising strategy for test anxiety.

Xiaoyaosan Improves Antibiotic-Induced Depressive-Like and Anxiety-Like Behavior in Mice Through Modulating the Gut Microbiota and Regulating the NLRP3 Inflammasome in the Colon

Disturbance of the gut microbiota plays an essential role in mental disorders such as depression and anxiety. Xiaoyaosan, a traditional Chinese medicine formula, has a wide therapeutic spectrum and is used especially in the management of depression and anxiety. In this study, we used an antibiotic-induced microbiome-depleted (AIMD) mouse model to determine the possible relationship between imbalance of the intestinal flora and behavioral abnormalities in rodents. We explored the regulatory effect of Xiaoyaosan on the intestinal flora and attempted to elucidate the potential mechanism of behavioral improvement. We screened NLRP3, ASC, and CASPASE-1 as target genes based on the changes in gut microbiota and explored the effect of Xiaoyaosan on the colonic NLRP3 pathway. After Xiaoyaosan intervention, AIMD mice showed a change in body weight and an improvement in depressive and anxious behaviors. Moreover, the gut flora diversity was significantly improved. Xiaoyaosan increased the abundance of Lachnospiraceae in AIMD mice and decreased that of Bacteroidaceae, the main lipopolysaccharide (LPS)-producing bacteria, resulting in decreased levels of LPS in feces, blood, and colon tissue. Moreover, serum levels of the inflammatory factor, IL-1β, and the levels of NLRP3, ASC, and CASPASE-1 mRNA and DNA in the colon were significantly reduced. Therefore, Xiaoyaosan may alleviate anxiety and depression by modulating the gut microbiota, correcting excessive LPS release, and inhibiting the immoderate activation of the NLRP3 inflammasome in the colon.

The Microbiota-Gut-Brain Axis: From Motility to Mood

The gut-brain axis plays an important role in maintaining homeostasis. Many intrinsic and extrinsic factors influence signaling along this axis, modulating the function of both the enteric and central nervous systems. More recently the role of the microbiome as an important factor in modulating gut-brain signaling has emerged and the concept of a microbiota-gut-brain axis has been established. In this review, we highlight the role of this axis in modulating enteric and central nervous system function and how this may impact disorders such as irritable bowel syndrome and disorders of mood and affect. We examine the overlapping biological constructs that underpin these disorders with a special emphasis on the neurotransmitter serotonin, which plays a key role in both the gastrointestinal tract and in the brain. Overall, it is clear that although animal studies have shown much promise, more progress is necessary before these findings can be translated for diagnostic and therapeutic benefit in patient populations.

Psychobiotic Supplementation of PS128TM Improves Stress, Anxiety, and Insomnia in Highly Stressed Information Technology Specialists: A Pilot Study

Background: Information technology (IT) is an industry related to the production of computers, information processing, and telecommunications. Such industries heavily rely on the knowledge and solutions provided by IT specialists. Previous reports found that the subjective stress scores were higher in IT specialists who developed diabetes, hypertension, and depression. Specific probiotics, known as psychobiotics, may alleviate stress and mood symptoms. This study aimed to examine whether an 8-week intervention of a novel psychobiotic, Lactobacillus plantarum PS128^TM (PS128^TM), improved self-perceived stress and mood symptoms among high-stress IT specialists.

Methods: This open-label, single-arm, baseline-controlled study included IT specialists from a large IT company in Northern Taiwan. Participants with a Perceived Stress Scale (PSS) 10-item version score of 27 or higher were included. Participants were asked to take two capsules containing PS128^TM powder, equivalent to 20 billion colony-forming units, daily. Self-report measures, such as the Job Stress Scale, Visual Analog Scale of Stress, the Insomnia Severity Index, the State and Trait Anxiety Index, the Questionnaire for Emotional Trait and State, the Patient Health Questionnaire, the Quality of Life Enjoyment and Satisfaction Questionnaire, and Gastrointestinal Severity Index were compared at baseline and at the end of the trial period. The primary outcome was a 20% reduction in the PSS score at endpoint. Objective measures included salivary levels of stress biomarkers, including cortisol, α-amylase, immunoglobulin A, lactoferrin, and lysozymes, as well as results of the Test of Attentional Performance.

Results: Of the 90 eligible IT specialists, 36 met the inclusion criteria. After the 8-week trial period, significant improvements in self-perceived stress, overall job stress, job burden, cortisol level, general or psychological health, anxiety, depression, sleep disturbances, quality of life, and both positive and negative emotions were found.

Conclusion: Our results suggest that PS128^TM has the distinct advantage of providing stress relief and can improve mental health for people with a high-stress job. Future placebo-controlled studies are warranted to explore the effect and underlying mechanisms of action of PS128^TM.

Clinical Trial Registration:https://clinicaltrials.gov/ (identifier: NCT04452253-sub-project 2).

What Makes a Successful Donor? Fecal Transplant from Anxious-Like Rats Does Not Prevent Spinal Cord Injury-Induced Dysbiosis

Spinal cord injury (SCI) causes gut dysbiosis and an increased prevalence of depression and anxiety. Previous research showed a link between these two consequences of SCI by using a fecal transplant from healthy rats which prevented both SCI-induced microbiota changes and the subsequent development of anxiety-like behaviour. However, whether the physical and mental state of the donor are important factors in the efficacy of FMT therapy after SCI remains unknown. In the present study, rats received a fecal transplant following SCI from uninjured donors with increased baseline levels of anxiety-like behaviour and reduced proportion of Lactobacillus in their stool. This fecal transplant increased intestinal permeability, induced anxiety-like behaviour, and resulted in minor but long-term alterations in the inflammatory state of the recipients compared to vehicle controls. There was no significant effect of the fecal transplant on motor recovery in rehabilitative training, suggesting that anxiety-like behaviour did not affect the motivation to participate in rehabilitative therapy. The results of this study emphasize the importance of considering both the microbiota composition and the mental state of the donor for fecal transplants following spinal cord injury.

Gut microbiota, kynurenine pathway and mental disorders - Review

The intestine and the gut-associated limphoid tissue constitute the largest immunity organ of the human body. Among several possible tryptophan metabolism routes, the kynurenine pathway can be influenced by the gut microbiota. Disturbances of gut biodiversity may cause increased gut permeability and cause systemic inflammation, also related to central nervous system. Proinflammatory cytokines induce kynurenine pathway enzymes resulting in formation of neuroactive metabolites, which are being associated with several psychiatric disorders. The kynurenine pathway may also be influenced by certain bacteria species directly. The aim of this review is to highlight the current knowledge on the interaction of gut microbiota and the central nervous system with the kynurenine pathway taken into special account. Up to date study results on specific psychiatric disorders such as schizophrenia, bipolar disorder, Alzheimer's disease, autism spectrum disorders, depression and alcoholism are presented. Available evidence suggests that toxicity of kynurenine metabolites may be reduced by adjunction of probiotics which can affect proinflammatory cytokines. Due to their potential for modulation of the kynurenine pathway, gut microbiota pose an interesting target for future therapies.

The gut-brain axis in irritable bowel syndrome and inflammatory bowel disease

Research increasingly demonstrates the bidirectional communication between gut microbiota and the brain, enhancing the role of gut microbiota modulation in the treatment of central nervous system (CNS) disorders. The first five years of life are extremely important as it affects the development of gut microbiota, immune system and, consequently, the onset of psychometric alterations, particularly in genetically predisposed individuals. In this review, we focus on the link between specific microbial genera, gastrointestinal (GI) disorders, anxiety and depression and on the effects of different therapeutic strategies for mood disorders on gut microbiota.

The effects of co-administration of probiotics and prebiotics on chronic inflammation, and depression symptoms in patients with coronary artery diseases: a randomized clinical trial

BACKGROUND

It has been shown that dysbiosis might have a role in developing of chronic inflammation and depression. In this study, we are interested in exploring of anti-inflammatory and anti-depressant effects of Lactobacillus Rhamnosus G (LGG), a probiotic strain, alone or in combination with a prebiotic, Inulin, in patients with coronary artery disease (CAD).

METHODS

This randomized, double-blind clinical trial was held on 96 patients with CAD. Patients were randomly allocated into four different groups: LGG [a capsule/day, contained 1.9 × 10⁹ colony-forming unit of Lactobacillus Rhamnosus G], inulin (15 g/day), co-supplemented (LGG and inulin), and placebo. Participants consumed the supplements for two months. Beck Depression Inventory (BDI), MacNew questionnaire and Spielberger state-trait anxiety inventory (STAI-Y) were used to assess depression, quality of life and anxiety, respectively. Serum levels of C-reactive protein (hs-CRP), lipopolysaccharide (LPS), tumor necrosis factor (TNF)-α, and Interleukin (IL)-10 were also measured.

RESULTS

Probiotic-Inulin Co-supplementation significantly decreased BDI (-11.52 ± 0+3.20 vs. +2.97 ± 0.39, P = 0.001), STAI-state (-17.63 ± 3.22 vs. -0.60 ± 0.33, P = 0.021), and STAI-trait (-24.31 ± 7.41 vs. -1.45 ± 0.66, P = 0.020) scores, hs-CRP (-1.69 ± 0+66 vs. +0.82 ± 0.39 mg/dL, P = 0.020), LPS (-22.02 ± 5.40 vs. +0.31 ± 0.18 (EU/L), P = 0.047), and TNF-α (-25.05 ± 7.41 vs. +0.79 ± 0.71 (ng/L), P = 0.032) in comparison to placebo.

CONCLUSION

Co-supplementation of probiotics and inulin in CAD subjects for eight weeks had beneficial effects on depression, anxiety, and inflammatory biomarkers. Adding inulin to probiotic supplements improved psychological outcomes and inflammatory biomarkers more effectively than two supplements separately.Trial registration: Iranian Registry of Clinical Trials identifier: IRCT20180712040438N4..

Effects of Microbiota Imbalance in Anxiety and Eating Disorders: Probiotics as Novel Therapeutic Approaches

Anxiety and eating disorders produce a physiological imbalance that triggers alterations in the abundance and composition of gut microbiota. Moreover, the gut–brain axis can be altered by several factors such as diet, lifestyle, infections, and antibiotic treatment. Diet alterations generate gut dysbiosis, which affects immune system responses, inflammation mechanisms, the intestinal permeability, as well as the production of short chain fatty acids and neurotransmitters by gut microbiota, which are essential to the correct function of neurological processes. Recent studies indicated that patients with generalized anxiety or eating disorders (anorexia nervosa, bulimia nervosa, and binge-eating disorders) show a specific profile of gut microbiota, and this imbalance can be partially restored after a single or multi-strain probiotic supplementation. Following the PRISMA methodology, the current review addresses the main microbial signatures observed in patients with generalized anxiety and/or eating disorders as well as the importance of probiotics as a preventive or a therapeutic tool in these pathologies.

Maternal Distress and Offspring Neurodevelopment: Challenges and Opportunities for Pre-clinical Research Models

Pre-natal exposure to acute maternal trauma or chronic maternal distress can confer increased risk for psychiatric disorders in later life. Acute maternal trauma is the result of unforeseen environmental or personal catastrophes, while chronic maternal distress is associated with anxiety or depression. Animal studies investigating the effects of pre-natal stress have largely used brief stress exposures during pregnancy to identify critical periods of fetal vulnerability, a paradigm which holds face validity to acute maternal trauma in humans. While understanding these effects is undoubtably important, the literature suggests maternal stress in humans is typically chronic and persistent from pre-conception through gestation. In this review, we provide evidence to this effect and suggest a realignment of current animal models to recapitulate this chronicity. We also consider candidate mediators, moderators and mechanisms of maternal distress, and suggest a wider breadth of research is needed, along with the incorporation of advanced -omics technologies, in order to understand the neurodevelopmental etiology of psychiatric risk.

Interplay of Good Bacteria and Central Nervous System: Cognitive Aspects and Mechanistic Considerations

The human gastrointestinal tract hosts trillions of microorganisms that is called “gut microbiota.” The gut microbiota is involved in a wide variety of physiological features and functions of the body. Thus, it is not surprising that any damage to the gut microbiota is associated with disorders in different body systems. Probiotics, defined as living microorganisms with health benefits for the host, can support or restore the composition of the gut microbiota. Numerous investigations have proved a relationship between the gut microbiota with normal brain function as well as many brain diseases, in which cognitive dysfunction is a common clinical problem. On the other hand, increasing evidence suggests that the existence of a healthy gut microbiota is crucial for normal cognitive processing. In this regard, interplay of the gut microbiota and cognition has been under focus of recent researches. In the present paper, I review findings of the studies considering beneficial effects of either gut microbiota or probiotic bacteria on the brain cognitive function in the healthy and disease statuses.

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

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

Probiotics as a treatment for prenatal maternal anxiety and depression: a double-blind randomized pilot trial

Probiotic use may be an efficacious treatment option to effectively manage symptoms of prenatal maternal anxiety and depression. Our primary aim was to test feasibility and acceptability for a probiotic randomized controlled trial (RCT) in pregnant women with pre-existing symptoms. This double-blind pilot RCT included 40 pregnant women with low-risk pregnancies and elevated depressive symptoms and/or anxiety. Once daily, participants orally consumed a probiotic (Ecologic Barrier) or a placebo, from 26 to 30 weeks gestation until delivery. A priori key progression criteria for primary outcomes were determined to decide whether or not a full RCT was feasible and acceptable. Secondary outcomes included depressive symptoms, anxiety, stress, and maternal bonding to offspring. In 19 months, 1573 women were screened; following screening, 155 women (10%) were invited for participation, of whom 135 (87%) received study information, and 40 women (30%) were included. Four out of six a priori determined criteria for success on feasibility and acceptability were met. After 8 weeks of intervention, there was no significant difference between the probiotic and placebo groups for secondary outcomes. The pilot trial was feasible and acceptable, but hampered by recruitment method and study design. Secondary endpoints did not reveal differences between the groups for improving maternal mood.

Short-Term Tolerability, Safety, and Gut Microbial Composition Responses to a Multi-Strain Probiotic Supplement: An Open-Label Study in Healthy Adults

BACKGROUND

Probiotics are among the most commonly used dietary supplements and evidence of their efficacy is increasing. Despite the long historical use of probiotics, some experts suggest that additional research is necessary to understand their potential risks.

OBJECTIVES

Main aims of this study were to assess short-term tolerability and safety of a new, high colony-forming unit count, multi-strain probiotic supplement. Exploratory objectives included evaluating effects on gut microbial composition.

METHODS

Ten healthy adults were enrolled in a single-arm, open-label study. Over a 10-day period, participants consumed a once daily probiotic capsule (2.1 x 1011 CFU) containing Lactobacillus acidophilus NCFM, Lactobacillus paracasei Lpc-37, Lactobacillus plantarum Lp-115, Lactobacillus rhamnosus GG, Lactobacillus rhamnosus HN001, Bifidobacterium lactis Bi-07, Bifidobacterium lactis Bl-04, and Bifidobacterium lactis HN019. The primary measure of tolerability pertained to whether or not participants completed the study. Secondary safety measures included clinical biomarkers from a routine metabolic panel and a complete blood count. Exploratory measures included stool microbiota counts.

RESULTS

All participants completed the study and there were no serious adverse events. All documented adverse events were prompted by the investigators and the most commonly reported symptoms were gastrointestinal. There was a single instance of a biomarker abnormality in one individual. Overall, decreases in total bilirubin and aspartate aminotransferase, and increases in stool levels of Lactobacillus species, Faecalibacterium prausnitzii, and Akkermansia muciniphila (P < .05) were observed over the course of the study.

CONCLUSIONS

The findings of this study suggest the multi-strain probiotic supplement was well-tolerated and most likely safe. Changes in liver function measures suggest the probiotics could potentially impact liver health. Stool microbiota changes suggest the probiotic could potentially impact gut health by affecting levels of intestinal microbiota that have been described as bioindicators of health and potential keystone species. However, additional research is necessary to follow up on the exploratory findings of this preliminary work.

Postpartum Depression: Current Status and Possible Identification Using Biomarkers

Postpartum depression (PPD) is a serious health issue that can affect about 15% of the female population within after giving birth. It often conveys significant negative consequences to the offsprings. The symptoms and risk factors are somewhat similar to those found in non-postpartum depression. The main difference resides in the fact that PPD is triggered by postpartum specific factors, including especially biological changes in the hormone levels. Patients are usually diagnosed using a questionnaire onsite or in a clinic. Treatment of PPD often involves psychotherapy and antidepressant medications. In recent years, there have been more researches on the identification of biological markers for PPD. In this review, we will focus on the current research status of PPD, with an emphasis on the recent progress made on the identification of PPD biomarkers.

Effectiveness of Probiotic, Prebiotic, and Synbiotic Supplementation to Improve Perinatal Mental Health in Mothers: A Systematic Review and Meta-Analysis

Introduction: There is an emerging interest in modulating the gut microbiota to target the gut-brain axis and improve maternal mental health in the perinatal period. This systematic review evaluated the effectiveness of prebiotics, probiotics, and synbiotics supplementation during pregnancy to reduce the risk of maternal mental health problems in the perinatal period. Methods: Electronic biomedical databases and clinical trial registries were searched from database inception through August 2020 to identify randomized controlled clinical trials (RCTs) evaluating the effect of probiotic, prebiotic, or synbiotic supplements administered to women during pregnancy on measures of perinatal depression, anxiety, and other mental health outcomes. Study selection, risk of bias appraisal, and data extraction were independently performed by two reviewers. Pooled mean differences (MD) and odds ratios (pOR) with 95% confidence intervals (CI) were calculated in random-effects meta-analyses for the outcomes of interest in the review. Results: From 3,868 studies identified through the search strategy, three RCTs of low risk of bias involving 713 participants were included, all three testing probiotics. There were no differences between probiotics and control groups in the mean depression scores (MD -0.46; 95% CI -2.16, 1.25) at end of follow-up. Although statistical significance was not achieved, probiotics showed an advantage in the proportion of participants scoring below an established cut-off for depression (pOR 0.68; 95% CI 0.43, 1.07). Compared to placebo, probiotics in pregnancy reduced anxiety symptoms (MD -0.99; 95% CI -1.80, -0.18); however, this advantage was not translated in a reduction in the proportion of participants scoring above an established cut-off for anxiety (pOR 0.65; 95% CI 0.23, 1.85). There were no differences between probiotics and control groups in global mental health scores at end of follow-up (MD 1.09; 95% CI -2.04, 4.22). Conclusion: There is limited but promising evidence about the effectiveness of probiotics during pregnancy to reduce anxiety symptoms and reduce the proportion of women scoring ABOVE a cut-off depression score. There is a lack of RCT evidence supporting prebiotics and synbiotics supplementation for similar purposes in the perinatal period. More research is needed before prebiotics, probiotics, and synbiotics are recommended to support maternal mental health and well-being in the perinatal period. Systematic Review Registration: PROSPERO, CRD42019137158.

Improvements in sleep indices during exam stress due to consumption of a Bifidobacterium longum

Targeting the gut microbiome as an effective therapeutic strategy for psychological disorders has shown promise in recent years. Variation in the composition of the microbiota and restoration of a stable microbiome using targeted interventions (psychobiotics) including Bifidobacteria have shown promise in pre-clinical studies, but more human data is required on the potential health benefits of these live microorganisms. Bifidobacterium including Bif. longum 1714 has been shown to dampen the effects of acute stress in humans. However, its effects over a period of prolonged stress have not been examined. A randomised, placebo-controlled, repeated measures, cross-over intervention study was conducted to examine the effects of a probiotic intervention on measures of stress, cognitive performance, and mood in healthy human volunteers. Twenty male students participated in this crossover study. Post-intervention assessments took place during the university exam period, which was used as a naturalistic chronic stressor. Self-reported measures of stress, depression, sleep quality, physical activity, gastrointestinal symptoms, cognition, and mood were assessed by questionnaire. In addition, tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were administered to all participants. Stress and depression scores increased in both placebo and probiotic treated groups during the exam period. While overall sleep quality and duration of sleep improved significantly in the probiotic treated group during exam stress compared with the placebo treated group, B. longum 1714, similar to placebo treatment, showed no efficacy in improving measures of working memory, visual memory, sustained attention or perception. Overall, while B. longum 1714 shows promise in improving sleep quality and duration, it did not alleviate symptoms of chronic stress, depression, or any measure of cognitive assessment. Thus, further mechanistic studies into the ability of B. longum 1714 to modulate sleep during prolonged periods of stress are now warranted.

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Using a repeated measures design ​we selected stress and cognitive tests that would examine memory and sustained attention.

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Bif. longum had a positive effect on self-reported sleep quality.

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Our data supports the potential role for probiotics in modulating brain health.

PROFAST: A Randomized Trial Assessing the Effects of Intermittent Fasting and Lacticaseibacillus rhamnosus Probiotic among People with Prediabetes

Both intermittent fasting and specific probiotics have shown promise in improving glucose tolerance with a potential for synergistic effects through alterations to gut microbiota. In this randomized, double-blinded, two-arm feasibility study, we investigated whether intermittent fasting, supplemented with Lacticaseibacillus rhamnosus HN001 probiotic, reduces HbA1c in individuals with prediabetes. All participants with HbA1c 40-50 mmol/mol commenced intermittent fasting (2 days per week of calorie restriction to 600-650 kcal/day) and were randomized 1:1 to either daily probiotic (Lacticaseibacillus rhamnosus HN001) or placebo for 12 weeks. The primary outcome was a change in HbA1c. Secondary outcomes included changes in anthropometry, body composition, glucoregulatory markers, lipids, hunger hormones, liver enzymes, inflammatory markers, gut hormones, calorie and macronutrient intake, quality of life, hunger, mood and eating behavior. Of 33 participants who commenced the trial, 26 participants (mean age 52 years, body mass index (BMI) 34.7 kg/m²) completed the intervention (n = 11 placebo, n = 15 probiotic). HbA1c decreased from 43 ± 2.7 mmol/mol to 41 ± 2.3 mmol/mol, p < 0.001, with average of 5% weight loss. No significant between-group differences were seen in primary or secondary outcomes except for social functioning (p = 0.050) and mental health (p = 0.007) scores as improvements were seen in the probiotic group, but not in the placebo group. This study shows additional psychological benefits of probiotic supplementation during intermittent fasting to achieve weight loss and glycemic improvement in prediabetes.

Gut Microbiota: A Perspective for Psychiatrists

There is mounting evidence that the trillions of microbes that inhabit our gut are a substantial contributing factor to mental health and, equally, to the progression of neuropsychiatric disorders. The extraordinary complexity of the gut ecosystem, and how it interacts with the intestinal epithelium to manifest physiological changes in the brain to influence mood and behaviour, has been the subject of intense scientific scrutiny over the last 2 decades. To further complicate matters, we each harbour a unique microbiota community that is subject to change by a number of factors including diet, exercise, stress, health status, genetics, medication, and age, amongst others. The microbiota-gut-brain axis is a dynamic matrix of tissues and organs including the gastrointestinal (GI) microbiota, immune cells, gut tissue, glands, the autonomic nervous system (ANS), and the brain that communicate in a complex multidirectional manner through a number of anatomically and physiologically distinct systems. Long-term perturbations to this homeostatic environment may contribute to the progression of a number of disorders by altering physiological processes including hypothalamic-pituitary-adrenal axis activation, neurotransmitter systems, immune function, and the inflammatory response. While an appropriate, co-ordinated physiological response, such as an immune or stress response, is necessary for survival, a dysfunctional response can be detrimental to the host, contributing to the development of a number of central nervous system disorders.

Effect of Probiotic Supplementation on Newborn Birth Weight for Mother with Gestational Diabetes Mellitus or Overweight/Obesity: A Systematic Review and Meta-Analysis

High birth weight indicates the future risk of obesity and increased fat mass in childhood. Maternal gestational diabetes mellitus (GDM) or overweight are powerful predictors of high birth weight. Studies on probiotic supplementation during pregnancy have reported its benefits in modulating gut microbiota composition and improving glucose and lipid metabolism in pregnant women. Therefore, probiotic intervention during pregnancy was proposed to interrupt the transmission of obesity from mothers to newborns. Thus, we performed a meta-analysis to investigate the effect of probiotic intervention in pregnant women with GDM or overweight on newborn birth weight. We searched PubMed, EMBASE, Cochrane Library, and Web of Science databases up to 18 December 2019. Randomized controlled trials (RCTs) comparing pregnant women with GDM or overweight who received probiotic intervention during pregnancy with those receiving placebo were eligible for the analysis. Newborn birth weights were pooled to calculate the mean difference with a 95% confidence interval (CI). Two reviewers assessed the trial quality and extracted data independently. Seven RCTs involving 1093 participants were included in the analysis. Compared with the placebo, probiotics had little effect on newborn birth weight of pregnant women with GDM or overweight (mean difference = -10.27, 95% CI = -90.17 to 69.63, p = 0.801). The subgroup analysis revealed that probiotic intake by women with GDM decreased newborn birth weight, whereas probiotic intake by obese pregnant women increased newborn birth weight. Thus, no evidence indicates that probiotic intake by pregnant women with GDM or overweight can control newborn birth weight.

Lacticaseibacillus paracasei Lpc-37® improves psychological and physiological markers of stress and anxiety in healthy adults: a randomized, double-blind, placebo-controlled and parallel clinical trial (the Sisu study)

Chronic stress is a risk-factor for the development of mood and stress-related disorders. Clinical evidence indicates that probiotics can influence the stress response and mood. The Sisu study investigated whether Lacticaseibacillus paracasei Lpc-37® (Lpc-37®) could modulate stress, mood and well-being. Prior to a two-week run-in period, 120 healthy adults (18-45 y) were stratified for sex and chronic stress and randomized to either 1.75 × 1010 colony forming units (CFU) of Lpc-37 or placebo (1:1) per day for 5 weeks. The primary objective was the effect of Lpc-37 on heart rate (HR) in response to the Trier Social Stress Test (TSST). Secondary objectives were assessed by biomarkers and self-report scales over the study. The primary hypothesis was not met in either the Intention-to-Treat (ITT) or Per Protocol (PP) population, but Lpc-37 reduced the increase in HR in participants with low chronic stress (LCS) and increased HR in participants with high chronic stress (HCS) during the TSST. Supporting significant efficacy in the PP population (n = 113), Lpc-37 reduced perceived stress following intervention. More significant effects were identified within the subgroups where Lpc-37 reduced exhaustion during the TSST and normalized cortisol levels at 8pm in participants with LCS, reduced perceived stress also in females, and increased perceived health and sleep-related recovery in participants with HCS. Adverse events (AEs) were similar between groups, there were no severe AEs, and vital signs remained unchanged. Overall, Lpc-37 reduced perceived stress compared to placebo. Other beneficial effects within biomarkers related to stress indicate that the effects of Lpc-37 may be differentially dependent on sex and chronic stress. (ClinicalTrials.gov: NCT03494725).

Nutrition, Microbiota and Role of Gut-Brain Axis in Subjects with Phenylketonuria (PKU): A Review

The composition and functioning of the gut microbiota, the complex population of microorganisms residing in the intestine, is strongly affected by endogenous and exogenous factors, among which diet is key. Important perturbations of the microbiota have been observed to contribute to disease risk, as in the case of neurological disorders, inflammatory bowel disease, obesity, diabetes, cardiovascular disease, among others. Although mechanisms are not fully clarified, nutrients interacting with the microbiota are thought to affect host metabolism, immune response or disrupt the protective functions of the intestinal barrier. Similarly, key intermediaries, whose presence may be strongly influenced by dietary habits, sustain the communication along the gut-brain-axis, influencing brain functions in the same way as the brain influences gut activity. Due to the role of diet in the modulation of the microbiota, its composition is of high interest in inherited errors of metabolism (IEMs) and may reveal an appealing therapeutic target. In IEMs, for example in phenylketonuria (PKU), since part of the therapeutic intervention is based on chronic or life-long tailored dietetic regimens, important variations of the microbial diversity or relative abundance have been observed. A holistic approach, including a healthy composition of the microbiota, is recommended to modulate host metabolism and affected neurological functions.

Gut-Brain Axis: Role of Gut Microbiota on Neurological Disorders and How Probiotics/Prebiotics Beneficially Modulate Microbial and Immune Pathways to Improve Brain Functions

The gut microbiome acts as an integral part of the gastrointestinal tract (GIT) that has the largest and vulnerable surface with desirable features to observe foods, nutrients, and environmental factors, as well as to differentiate commensals, invading pathogens, and others. It is well-known that the gut has a strong connection with the central nervous system (CNS) in the context of health and disease. A healthy gut with diverse microbes is vital for normal brain functions and emotional behaviors. In addition, the CNS controls most aspects of the GI physiology. The molecular interaction between the gut/microbiome and CNS is complex and bidirectional, ensuring the maintenance of gut homeostasis and proper digestion. Besides this, several mechanisms have been proposed, including endocrine, neuronal, toll-like receptor, and metabolites-dependent pathways. Changes in the bidirectional relationship between the GIT and CNS are linked with the pathogenesis of gastrointestinal and neurological disorders; therefore, the microbiota/gut-and-brain axis is an emerging and widely accepted concept. In this review, we summarize the recent findings supporting the role of the gut microbiota and immune system on the maintenance of brain functions and the development of neurological disorders. In addition, we highlight the recent advances in improving of neurological diseases by probiotics/prebiotics/synbiotics and fecal microbiota transplantation via the concept of the gut-brain axis.

Perinatal depression: Heterogeneity of disease and in animal models

Perinatal depression (PND) can have either an antepartum or postpartum onset. Although the greatest risk factor for PND is previous depression history,de novoPND occurs with the majority of cases occurring in the postpartum. Timing of depression can impact etiology, prognosis, and response to treatment. Thus, it is crucial to study the impact of the heterogeneity of PND for better health outcomes. In this review, we outline the differences between antepartum and postpartum depression onset of PND. We discuss maternal physiological changes that differ between pregnancy and postpartum and how these may differentially impact depression susceptibility. We highlight changes in the maternal steroid and peptide hormone levels, immune signalling, serotonergic tone, metabolic factors, brain morphology, and the gut microbiome. Finally, we argue that studying the heterogeneity of PND in clinical and preclinical models can lead to improved knowledge of disease etiopathology and treatment outcomes.

Fecal Microbiota Changes in Patients With Postpartum Depressive Disorder

Postpartum depressive disorder (PPD) is a unique subtype of major depressive disorder and a substantial contributor to maternal morbidity and mortality. However, the pathogenesis of PPD has still remained elusive, and it may associate with genetic and environmental factors. Gut microbiota has already been proved to be associated with depression; however, a limited number of studies have concentrated on PPD. The present study aimed to explore the potential correlations between gut microbiota and PPD. In this study, 57 participants were enrolled, in which fecal samples of 28 patients with PPD and 16 healthy controls (HCs) were collected and then analyzed by high-throughput sequencing of the 16S ribosomal RNA (rRNA) gene. The results showed that diversity and composition of gut microbial communities were partly different between PPD patients and HCs. The relative abundance of Firmicutes phyla was lower in PPD patients. The levels of several predominant genera were significantly different between PPD patients and HCs. More importantly, the PPD patients experienced reduced levels of Faecalibacterium, Phascolarctobacterium, Butyricicoccus, and Lachnospiraceae, as well as increased levels of Enterobacteriaceae family. In addition, a correlation was observed between levels of Phascolarctobacterium, Lachnospiraceae, Faecalibacterium, and Tyzzerella.3 and the severity of depressive symptoms. Various kinds of bacteria, such as Lachnospiraceae and Faecalibacterium, were found to be associated with levels of sex hormones. This study indicated the correlation between gut microbiota and PPD, and gut microbiota-based biomarkers may be helpful for the diagnosis and treatment of PPD patients. However, further studies need to be conducted to clarify the cause–effect relationship between PPD patients and gut microbiota and to highlight the suitability of gut microbiome as a biomarker.

Pre-Gestational intake of Lactobacillus helveticus NS8 has anxiolytic effects in adolescent Sprague Dawley offspring

INTRODUCTION

Adolescence is a period of heightened susceptibility to anxiety disorders. Probiotic supplementation had a positive impact on reducing anxiety. The maternal microbiome plays an important role in child health outcomes and in the establishment of the offspring microbiome. Few studies have investigated the impact of gestational probiotic supplementation on the offspring's anxiety.

METHODS

The present study examined the impact of prenatal Lactobacillus helveticus NS8 supplementation (LAC) on Sprague Dawley rat offspring's anxiety-like behavior. The behaviors tested in the present study include the elevated plus maze (EPM), the open field test (OFT), and prepulse inhibition (PPI). Analyses of variance were utilized.

RESULTS

(a) The performance of LAC adolescent rats in the EPM was similar to that in the OFT, both of which reflect that LAC caused an antianxiety effect in adolescent offspring rats and the antianxiety effect without sex differences; (b) LAC did not change performance in PPI and did not change the sex and age differences in PPI; and c. LAC decreased the body mass of rat offspring.

CONCLUSION

Lactobacillus helveticus NS8 supplementation during gestation might have a moderate antianxiety effect in both males and females (especially adolescents) and be helpful for avoiding excessive body mass.

The Effect of Probiotic Supplementation on Depressive Symptoms and Quality of Life in Patients After Myocardial Infarction: Results of a Preliminary Double-Blind Clinical Trial

OBJECTIVE

Evidence indicates that probiotic supplements may improve or prevent depression. Little is known about the effects of probiotic supplementation on symptoms of depression and quality of life (QOL) in patients with myocardial infarction (MI).

METHODS

This randomized, double-blind, and placebo-controlled clinical trial was performed in 44 patients with a recent diagnosis of MI who underwent percutaneous coronary intervention. Patients were randomly assigned to receive either capsules containing 1.6 × 10 colony-forming units of Lactobacillus rhamnosus capsules with their lunch (the active intervention group) or capsules that contained maltodextrin (the placebo control group) for 12 weeks. The Beck Depression Inventory, QOL, and biomarkers of oxidative stress (serum total antioxidant capacity), and malondialdehyde), and high-sensitivity C-reactive protein (hs-CRP) as inflammation marker were assessed. These measures were obtained at baseline and at 12 weeks' follow-up.

RESULTS

The total Beck Depression Inventory score decreased significantly in patients who received probiotic supplements compared with the placebo group (-5.57 [6.1] versus -0.51 [2.8], p = .045). Improvements in the mean QOL score were also stronger in the probiotic versus the placebo group (23.6 [39.1] versus 0.44 [42.6], p = .023). In addition, increases in total antioxidant capacity (93.7 [88.4] versus 27.54 [64.7] mmol/l, p = .009) and decreases in malondialdehyde (-40.7 [63.73] versus -4.2 [67.6] nmol/ml, p = .033) and high-sensitivity C-reactive protein (-1.74 [0.70] versus 0.67 [1.27] mg/l, p = .040) levels were stronger in patients receiving probiotic supplementation than the placebo group.

CONCLUSION

These data provide preliminary evidence that probiotic supplementation in patients with percutaneous coronary intervention post-MI has beneficial effects on depressive symptoms and markers of oxidative stress and inflammation. Multicenter studies with larger sample sizes are needed to replicate these findings and identify patient subgroups with the most benefit from probiotic supplementation.

TRIAL REGISTRATION

www.irct.ir identifier: IRCT20121028011288N15.

Precision medicine in perinatal depression in light of the human microbiome

Perinatal depression is the most common complication of pregnancy and affects the mother, fetus, and infant. Recent preclinical studies and a limited number of clinical studies have suggested an influence of the gut microbiome on the onset and course of mental health disorders. In this review, we examine the current state of knowledge regarding genetics, epigenetics, heritability, and neuro-immuno-endocrine systems biology in perinatal mood disorders, with a particular focus on the interaction between these factors and the gut microbiome, which is mediated via the gut-brain axis. We also provide an overview of experimental and analytical methods that are currently available to researchers interested in elucidating the influence of the gut microbiome on mental health disorders during pregnancy and postpartum.

Current Perspectives on Gut Microbiome Dysbiosis and Depression

The human gut microbiome partakes in a bidirectional communication pathway with the central nervous system (CNS), named the microbiota–gut–brain axis. The microbiota–gut–brain axis is believed to modulate various central processes through the vagus nerve as well as production of microbial metabolites and immune mediators which trigger changes in neurotransmission, neuroinflammation, and behavior. Little is understood about the utilization of microbiome manipulation to treat disease. Though studies exploring the role of the microbiome in various disease processes have shown promise, mechanisms remain unclear and evidence-based treatments for most illnesses have not yet been developed. The animal studies reviewed here offer an excellent array of basic science research that continues to clarify mechanisms by which the microbiome may affect mental health. More evidence is needed, particularly as it relates to translating this work to human subjects. The studies presented in this paper largely demonstrate encouraging results in the treatment of depression. Limitations include small sample sizes and heterogeneous methodology. The exact mechanism by which the gut microbiota causes or alters neuropsychiatric disease states is not fully understood. In this review, we focus on recent studies investigating the relationship between gut microbiome dysbiosis and the pathogenesis of depression. This article is based on previously conducted studies and does not contain any studies with human participants or animals performed by any of the authors.

Association between habitual weekday sleep duration and depressive symptoms among Chinese adolescents:The role of mode of birth delivery

BACKGROUND

Depressive symptoms among adolescents are common. This study aimed to assess, among Chinese adolescents, the associations of habitual weekday sleep duration with depressive symptoms and whether these associations varied with the mode of birth delivery.

METHODS

Data were from the 2015 School-based Chinese Adolescents Health Survey, and 150,053 students' questionnaires were qualified for analysis. Multi-level logistic regression models were performed.

RESULTS

A weekday sleep duration of ≤5 h/night was associated with depressive symptoms (adjusted odds ratio [aOR]=2.98, 95% CI=2.75-3.24), and adolescents who reported a weekday sleep duration of 5-7 h/night (aOR=1.69, 95% CI=1.60-1.79) and >9 h/night (aOR=1.28, 95% CI=1.11-1.45) were also at a higher risk of depressive symptoms. Stratification analyses showed that in both adolescents delivered by vaginal birth and cesarean section (CS), a weekday sleep duration of ≤5 h/night, 5-7 h/night, and >9 h/night were associated with the increased risk of depressive symptoms in the adjusted models, and the magnitudes of the aORs in adolescents delivered by CS were slightly higher than those in adolescents delivered by vaginal birth.

LIMITATIONS

The cross-sectional study design and self-reported sleep duration and depressive symptoms.

CONCLUSION

This study demonstrates a significant U-shaped association between weekday sleep duration and depressive symptoms among Chinese adolescents. In both adolescents delivered by vaginal birth and CS, those who reported having abnormal sleep duration were at a high risk of depressive symptoms. Based on the findings of this study, we suggest sleep duration and mode of delivery should be a matter of concern for public health authorities.

Modulation of the intestinal microbiota and the metabolites produced by the administration of ice cream and a dietary supplement containing the same probiotics

The aim of the present work was to compare the capacity to modulate the intestinal microbiota and the production of metabolites after 14 d administration of a commercial dietary supplement and a manufactured ice cream, both containing the same quantity of inulin and the same viable counts of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis BB-12, using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) model. Samples of the colonic contents were evaluated microbiologically by real-time quantitative PCR (qRT-PCR) and next-generation sequencing and chemically by the production of SCFA (acetate, propionate and butyrate) and ammonium ions ($\text{NH}_4^ + $). Statistical analyses were carried out for all the variables using the two-way ANOVA followed by the Tukey multiple comparisons test (P < 0·05) for metabolite production, qRT-PCR and the bioinformatics analysis for microbiota diversity. Dietary supplement and ice cream were able to deliver the probiotic L. acidophilus and B. animalis to the simulated colon and modulate the microbiota, increasing beneficial micro-organisms such as Bifidobacterium spp., Bacteroides spp. and Faecalibacterium spp. for dietary supplement administration, and Lactobacillus spp. for ice cream supplementation. However, the ice cream matrix was probably more favourable for the maintenance of the metabolic activity of the probiotics in the SHIME® model, due to the larger amounts of acetate, propionate, butyrate and ammonium ions obtained after 14 d of supplementation. In conclusion, both ways of probiotic supplementation could be efficient, each with its own particularities.

Effect of heat-inactivated Lactobacillus paracasei N1115 on microbiota and gut-brain axis related molecules

This study was conducted to evaluate the possibility of using heated-inactivated lactobacilli to protect neonates from harmful effects of antibiotics. Thirty neonate mice were randomly divided into three groups of ten and treated with either sterilized water, an antibiotics cocktail, or the same antibiotics plus heat-inactivated Lactobacillus paracasei N1115. The administration of antibiotics significantly increased the serum interleukin-6 (IL-6) levels of the tested mice (p<0.01, p<0.001, respectively) and decreased their serum corticosterone levels (p<0.01, p<0.01, respectively). The colonic crypts were significantly less deep in mice treated with antibiotics and with antibiotics plus N1115 (p<0.05). Antibiotics caused significantly abnormal expression of brain-derived neurotrophic factor (BDNF), γ-aminobutyric acid type A receptor α1 (GABA_Aα1), γ-aminobutyric acid type B receptor1 (GABA_b1), and 5-hydroxytryptamine receptor1A (5-HT_1A) in the hippocampus (p<0.05, p<0.01, p<0.01, respectively) and of GABA_Aα1 in the prefrontal cortex (p<0.01). Heat-inactivated lactobacilli alleviated these abnormal changes. Antibiotics greatly decreased the Shannon index of the fecal microbiota and significantly increased the number of Proteobacteria (p<0.001), with fewer Bacteroidetes and Firmicutes (p<0.05). Antibiotics not only cause microbiota dysbiosis, but also cause abnormal changes in important molecules in the gut-brain axis. All these abnormal changes are alleviated by heat-inactivated L. paracasei N1115. This indicates that heat-inactivated L. paracasei N1115 has a certain improvement effect on changes caused by antibiotics.

Finding intestinal fortitude: Integrating the microbiome into a holistic view of depression mechanisms, treatment, and resilience

Depression affects at least 322 million people globally, or approximately 4.4% of the world's population. While the earnestness of researchers and clinicians to understand and treat depression is not waning, the number of individuals suffering from depression continues to increase over and above the rate of global population growth. There is a sincere need for a paradigm shift. Research in the past decade is beginning to take a more holistic approach to understanding depression etiology and treatment, integrating multiple body systems into whole-body conceptualizations of this mental health affliction. Evidence supports the hypothesis that the gut microbiome, or the collective trillions of microbes inhabiting the gastrointestinal tract, is an important factor determining both the risk of development of depression and persistence of depressive symptoms. This review discusses recent advances in both rodent and human research that explore bidirectional communication between the gut microbiome and the immune, endocrine, and central nervous systems implicated in the etiology and pathophysiology of depression. Through interactions with circulating inflammatory markers and hormones, afferent and efferent neural systems, and other, more niche, pathways, the gut microbiome can affect behavior to facilitate the development of depression, exacerbate current symptoms, or contribute to treatment and resilience. While the challenge of depression may be the direst mental health crisis of our age, new discoveries in the gut microbiome, when integrated into a holistic perspective, hold great promise for the future of positive mental health.

Probiotics and Maternal Mental Health: A Randomised Controlled Trial among Pregnant Women with Obesity

Poor maternal mental health has been associated with a myriad of pregnancy and child health complications. Obesity in pregnancy is known to increase one’s risk of experiencing poor maternal mental health and associated physical and mental health complications. Probiotics may represent a novel approach to intervene in poor mental health and obesity. We conducted this pre-specified secondary analysis of the Healthy Mums and Babies (HUMBA) randomised controlled trial to investigate whether probiotics would improve maternal mental health outcomes up to 36 weeks of pregnancy. Two-hundred-and-thirty pregnant women with obesity (BMI ≥ 30.0 kg/m²) were recruited and randomised to receive probiotic (Lactobacillus rhamnosus GG and Bifidobacterium lactis BB12, minimum 6.5 × 10⁹ CFU) or placebo capsules. Depression, anxiety, and functional health and well-being were assessed at baseline (12⁰−17⁶ weeks’ gestation) and 36 weeks of pregnancy. Depression scores remained stable and did not differ between the probiotic (M = 7.18, SD = 3.80) and placebo groups (M = 6.76, SD = 4.65) at 36 weeks (p-values > 0.05). Anxiety and physical well-being scores worsened over time irrespective of group allocation, and mental well-being scores did not differ between the two groups at 36 weeks. Probiotics did not improve mental health outcomes in this multi-ethnic cohort of pregnant women with obesity.

Maternal psychological distress before birth influences gut immunity in mid-infancy

BACKGROUND

Maternal pre-postnatal psychosocial distress increases the risk for childhood allergic disease. This may occur through a host immunity pathway that involves intestinal secretory immunoglobulin A (sIgA). Experimental animal models show changes in the gut microbiome and immunity of offspring when exposed to direct or prenatal maternal stress, but little is known in humans.

OBJECTIVE

We determined the association between maternal depression and stress symptom trajectories and infant fecal sIgA concentrations.

METHODS

1043 term infants from the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort were studied. Trajectories of maternal perceived stress and depression were based on scored scales administered in pregnancy and postpartum. sIgA was quantified in infant stool (mean age 3.7 months) with Immundiagnostik ELISA. Linear regression and logistic regression were employed to test associations.

RESULTS

Very low fecal sIgA concentrations were more common in infants of mothers in the antepartum and persistent depression trajectories (6% and 2% of women, respectively). Independent of breastfeeding status at fecal sampling, infant antibiotic exposure or other covariates, the antepartum depressive symptom trajectory was associated with reduced mean infant sIgA concentrations (β=-0.07, P < .01) and a two fold risk for lowest quartile concentrations (OR, 1.86; 95% CI: 1.02, 3.40). This lowering of sIgA yielded a large effect size in older infants (4-8 months)-breastfed and not. No associations were seen with postpartum depressive symptoms (7% of women) or with any of the perceived stress trajectories.

CONCLUSION AND CLINICAL RELEVANCE

Despite improved mood postpartum and independent of breastfeeding status, mothers experiencing antepartum depressive symptoms delivered offspring who exhibited lower fecal sIgA concentrations especially in later infancy. The implications of lowered sIgA concentrations in infant stool are altered microbe-sIgA interactions, greater risk for C difficile colonization and atopic disease in later years.

Antidepressive Mechanisms of Probiotics and Their Therapeutic Potential

The accumulating knowledge of the host-microbiota interplay gives rise to the microbiota-gut-brain (MGB) axis. The MGB axis depicts the interkingdom communication between the gut microbiota and the brain. This communication process involves the endocrine, immune and neurotransmitters systems. Dysfunction of these systems, along with the presence of gut dysbiosis, have been detected among clinically depressed patients. This implicates the involvement of a maladaptive MGB axis in the pathophysiology of depression. Depression refers to symptoms that characterize major depressive disorder (MDD), a mood disorder with a disease burden that rivals that of heart diseases. The use of probiotics to treat depression has gained attention in recent years, as evidenced by increasing numbers of animal and human studies that have supported the antidepressive efficacy of probiotics. Physiological changes observed in these studies allow for the elucidation of probiotics antidepressive mechanisms, which ultimately aim to restore proper functioning of the MGB axis. However, the understanding of mechanisms does not yet complete the endeavor in applying probiotics to treat MDD. Other challenges remain which include the heterogeneous nature of both the gut microbiota composition and depressive symptoms in the clinical setting. Nevertheless, probiotics offer some advantages over standard pharmaceutical antidepressants, in terms of residual symptoms, side effects and stigma involved. This review outlines antidepressive mechanisms of probiotics based on the currently available literature and discusses therapeutic potentials of probiotics for depression.

Healthy Eating, Physical Activity, and Sleep Hygiene (HEPAS) as the Winning Triad for Sustaining Physical and Mental Health in Patients at Risk for or with Neuropsychiatric Disorders: Considerations for Clinical Practice

Neuropsychiatric disorders stem from gene-environment interaction and their development can be, at least in some cases, prevented by the adoption of healthy and protective lifestyles. Once full blown, neuropsychiatric disorders are prevalent conditions that patients live with a great burden of disability. Indeed, the determinants that increase the affliction of neuropsychiatric disorders are various, with unhealthy lifestyles providing a significant contribution in the interplay between genetic, epigenetic, and environmental factors that ultimately represent the pathophysiological basis of these impairing conditions. On one hand, the adoption of Healthy Eating education, Physical Activity programs, and Sleep hygiene promotion (HEPAS) has the potential to become one of the most suitable interventions to reduce the risk to develop neuropsychiatric disorders, while, on the other hand, its integration with pharmacological and psychological therapies seems to be essential in the overall management of neuropsychiatric disorders in order to reduce the disability and improve the quality of life of affected patients. We present an overview of the current evidence in relation to HEPAS components in the prevention and management of neuropsychiatric disorders and provide suggestions for clinical practice.

You've got male: Sex and the microbiota-gut-brain axis across the lifespan

Sex is a critical factor in the diagnosis and development of a number of mental health disorders including autism, schizophrenia, depression, anxiety, Parkinson's disease, multiple sclerosis, anorexia nervosa and others; likely due to differences in sex steroid hormones and genetics. Recent evidence suggests that sex can also influence the complexity and diversity of microbes that we harbour in our gut; and reciprocally that our gut microbes can directly and indirectly influence sex steroid hormones and central gene activation. There is a growing emphasis on the role of gastrointestinal microbiota in the maintenance of mental health and their role in the pathogenesis of disease. In this review, we introduce mechanisms by which gastrointestinal microbiota are thought to mediate positive health benefits along the gut-brain axis, we report how they may be modulated by sex, the role they play in sex steroid hormone regulation, and their sex-specific effects in various disorders relating to mental health.