Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects. Br J Nutr. 2011;105:755-764. [PMID: 20974015 DOI: 10.1017/s0007114510004319]

Probiotics Encapsulated via Biological Macromolecule for Neurological Therapy and Functional Food: A Review

Probiotics are live microorganisms that confer health benefits to humans, offering significant potential for preventing and treating various diseases. Neurological disorders, driven by multifaceted factors and linked to high disability rates, have become a growing global concern, particularly in the context of an aging population. Recent studies emphasize a strong connection between dysbiosis of the gut microbiota and neurological disorders. Probiotics have emerged as promising therapeutic interventions due to their ability to modulate the gut microbiota and influence the production of key metabolites, such as short-chain fatty acids and neurotransmitters, crucial for neurological health. However, probiotic viability is often compromised, limiting their therapeutic efficacy. We propose that developing high-activity probiotic formulations, coupled with innovative delivery strategies, holds considerable promise for advancing neurological treatments. Encapsulation systems have proven effective in enhancing probiotic stability and efficacy. This review discusses advances in probiotic delivery using biological macromolecule-based encapsulation, addressing key challenges in maintaining viability during production, storage, and digestion. It also highlights emerging delivery systems, such as microencapsulation, aimed at improving stability and therapeutic effectiveness. Additionally, the review explores the potential of functional foods enriched with probiotics for neurological health. Future research should explore clinical applications of encapsulated probiotics and support the development of functional foods to enhance neurological health.

Gut microbiota and the tryptophan-kynurenine pathway in anxiety: new insights and treatment strategies

Anxiety disorders are mental health disorders characterized by long-lasting fear, worry, nervousness, and alterations in gut microbiota (GM). The GM is a vital modulator of brain function through the gut-brain axis, which acts as the neural pathway between the central and peripheral nervous systems. Dysbiosis of GM plays an essential role in anxiety development because of alterations in the vagus nerve, increased intestinal permeability, and altered breakdown of tryptophan (TRP). The Kynurenine (KYN) pathway plays a crucial role in the pathogenesis of anxiety disorders, primarily through its neuroprotective (KYNA) and neurotoxic (QUIN) metabolites. Higher ratios of KYNA/QUIN result in neuroprotection, whereas higher KYN/TRP ratios indicate increased QUIN production causing neuroinflammation. Studies on germ-free models exhibit higher plasma TRP levels, which interrupt the metabolic balance of TRP-derived compounds, thus causing brain impairment. A key issue in anxiety disorders is the dysregulation of GM, which disrupts TRP metabolism and neuroinflammatory pathways, however, remains poorly understood. Hence, the proper understanding of these mechanisms is crucial for future therapeutic advancements. Here, we highlight the significance of the TRP-KYN pathway and the potential of modulating KYN pathway enzymes, such as kynurenine aminotransferases (KATs), to adjust KYNA levels and restore neurotransmitter balance. It further discusses new therapeutic methods with a particular focus on probiotics that may restore GM and modulate TRP metabolism. Advancing our understanding of the intricate relationship between GM and anxiety disorders may facilitate novel, microbiota-targeted interventions. This ultimately contributes to precision medicine approaches in mental health care, thereby enhancing treatment efficacy and patient outcomes.

Synbiotics of encapsulated Limosilactobacillus fermentum K73 promotes in vitro favorable gut microbiota shifts and enhances short-chain fatty acid production in fecal samples of children with autism spectrum disorder

Modulation of the gut microbiota has emerged as a promising approach for addressing the gastrointestinal and neurodevelopmental symptoms associated with autism spectrum disorder (ASD). Consequently, this study aimed to evaluate the impact of four formulated synbiotics comprising Limoscilactobacillus fermentum K73, high-oleic palm oil and whey, on the gut microbiota composition of Colombian children with and without ASD. These components were encapsulated through high-shear emulsification and spray drying. The four synbiotics and their individual components were subjected to in vitro digestion and fermentation using samples of Colombian children gut microbiota. Short-chain fatty acids (SCFAs), including lactic, acetic, propionic, and butyric acids, were quantified using HPLC-DAD, while serotonin was determined by an ELISA kit after in vitro fermentations. Changes in microbial structure were assessed by the sequencing of the 16S rRNA gene via next-generation sequencing (NGS). The results revealed a decrease in the abundance of genera like Bacteroides and Dorea in ASD-associated samples after the treatment with the synbiotics. Conversely, an increase in the relative abundance of probiotic-related genera, including Lactobacillus, Streptococcus, and Anaerostipes, was observed. Furthermore, the analysis of SCFAs and serotonin indicated that the synbiotic intervention resulted in an elevated butyric acid and microbial serotonin synthesis, alongside a decrease in propionic acid, which is changes considered beneficial in the context of ASD. This evidence suggests that synbiotics of L. fermentum K73 could represent a promising live biotherapeutic strategy for modulating the gut microbiota of children with ASD.

Combined Administration of Lactobacillus or Bifidobacterium Offers Enhanced Antidepressant and Anxiolytic Activity in a Dose Dependent Manner

PURPOSE

Gut microbiota is strongly linked to the activity of the bidirectional gut-brain axis, which influences neuropsychological processes at multiple levels. Changes in the gut microbiota have been implicated in mood disorders, and probiotics have been explored for their ability to mitigate the effects of stress on mental health. Here, we investigated the therapeutic benefits of different concentrations and combinations of Lactobacillus and Bifidobacterium in a mouse model of stress induced depression and anxiety.

METHODS

Sixty-three male ICR mice (6-8 weeks old; 20-25g) divided into nine groups were used for this study. The test groups underwent chronic unpredictable mild stress protocols for two weeks before receiving low (104 CFU/ml) or high (108 CFU/ml) doses of either monotherapy (Lactobacillus or Bifidobacterium) or a combination therapy (Lactobacillus and Bifidobacterium) for four weeks. The antidepressant, fluoxetine, served as the positive control. Measurements of weight and sucrose preference were performed at four time points in addition to a battery of behavioral tests (open field tests, forced swim test, tail suspension test, and hot plate test) at the endpoint to assess depression and anxiety-like behavior.

RESULTS

Low doses of the probiotic formulation (mono- or combined therapy) reversed weight loss but not anhedonia. In contrast, high doses of probiotic formulations (mono- or combined therapy), along with fluoxetine, were effective in reversing the weight loss and anhedonia caused by chronic unpredictable mild stress. Probiotics ameliorated stress-induced immobility as measured by both the forced swim and tail suspension tests, while also reducing anxiety-like behavior (increased peripheral activity) in the open field test. High doses of mono- or combined therapy increased curling behavior in the tail suspension test, whereas fluoxetine failed to do so.

CONCLUSION

This study indicates the species- and dose-dependent beneficial effects of probiotics on behavioral outcomes associated with depression while also reversing weight loss. Evidence suggests that probiotics and fluoxetine may exert antidepressant activity via different mechanisms.

Modulating Gut Microbiota with Dietary Components: A Novel Strategy for Cancer-Depression Comorbidity Management

BACKGROUND

Gut microbiota play a critical role in mediating the bidirectional association between cancer and depression. Emerging evidence indicates that adjusting the dietary component intake can significantly alter gut microbiota composition, thereby influencing the host's metabolism and immune function. Changes in gut microbiota and their metabolites may represent key factors in preventing cancer-depression comorbidity.

METHODS

English publications were searched in databases including the Web of Science, Scopus, and PubMed using a series of keywords: "cancer", "depression", "gut microbiota", "dietary components", and related terms, individually or in combination. The search focused on preclinical and clinical studies describing the regulatory effects of dietary component interventions.

RESULTS

This narrative review summarizes the associations among gut microbiota, cancer, and depression, and synthesizes current evidence on the modulatory effects and mechanisms of specific dietary component interventions, including dietary patterns, probiotics, prebiotics, and diet-derived phytochemicals, on gut microbiota. On the one hand, these interventions inhibit abnormal proliferation signals in the tumor microenvironment and enhance anticancer immune responses; on the other hand, they modulate neurotransmitter homeostasis, suppress neuroinflammation, and improve mood behaviors through the gut-brain axis interactions mediated by microbial metabolites.

CONCLUSIONS

The complex associations among cancer, depression, and gut microbiota require further clarification. Modulating gut microbiota composition through dietary components represents a novel therapeutic strategy for improving cancer-depression comorbidity. Regulated gut microbiota enhance immune homeostasis and intestinal barrier function, while their metabolites bidirectionally modulate one another via systemic circulation and the gut-brain axis, thereby improving both the tumor microenvironment and depressive-like behaviors in cancer patients while reducing the adverse effects of cancer.

Bidirectional Relationship Between Nutrition and Mental Health and Its Impact on the Health of Canadian Immigrants: An Integrative Review

Background: Immigration is a key factor contributing to population growth in Canada, a trend that is expected to continue. Immigrants generally arrive with better health than the Canadian-born population, but this advantage often diminishes over time, partially due to dietary acculturation. Emerging evidence points to a bidirectional link between nutrition and mental health. Objective: To explore the bidirectional relationship between nutrition and mental health and its impact on the health of Canadian immigrants, with a specific focus on immigrants' mental health and the healthy immigrant effect. Methods: For this integrative review, two comprehensive literature searches were conducted in the databases MEDLINE, CINAHL, Embase, PsycINFO, Scopus, and Web of Science from inception to July 2024. The review adhered to Whittemore and Knafl's integrative methodology, with the Mixed Methods Assessment Tool used to assess the quality of the studies. Results: A total of 42 and 34 scientific articles were included from the first and second literature searches, respectively. Four main themes emerged from the literature: (1) food insecurity and mental health, (2) obesity and mental health, (3) diet quality and mental health, and (4) the gut microbiome and mental health. These themes were explored in the context of Canadian immigrants' health. Conclusions: The health of immigrants to Canada is likely shaped by complex, bidirectional interactions among various determinants of health, influencing both physical and mental well-being. As newcomers are expected to form an increasing proportion of the Canadian population, further research is needed to understand how the interaction between nutrition and mental health can help promote and safeguard the health of Canadian immigrants.

Effects of Probiotics as Adjunctive Therapy to Fluoxetine on Depression Severity and Serum Brain-Derived Neurotrophic Factor, Cortisol, and Adrenocorticotropic Hormone in Patients With Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial

Probiotics may improve mood, but their role as adjunctive therapy for major depressive disorder (MDD) is not well understood. This study examines the effects of probiotics on depression severity, brain-derived neurotrophic factor (BDNF), adrenocorticotropic hormone (ACTH), and cortisol levels in MDD patients. Fifty medication-free MDD patients were randomized to receive probiotics with fluoxetine (n = 25) or placebo with fluoxetine (n = 25) for 8 weeks. Depression severity was assessed using the Hamilton Depression Rating Scale (HDRS-24), and fasting blood samples were collected at baseline and study conclusion. Forty-four patients completed the trial. The probiotic group showed a significant reduction in depression severity compared with the placebo group (p = 0.001). No significant differences were observed in serum cortisol (p = 0.46) and ACTH levels (p = 0.44). Plasma BDNF levels increased slightly in the probiotic group but were not statistically significant. Probiotic supplementation with fluoxetine significantly reduces depression severity in MDD patients.

Preventive and therapeutic impact of probiotic supplementation on behavior and inflammatory responses in the PTZ-induced chemical kindling in rats

INTRODUCTION

Epilepsy is a common neurological disorder that affects the quality of life globally. Its pathophysiology involves disruptions in ion transport, excitatory-inhibitory imbalances, and regulatory systems. It has been shown that there is a crosstalk between the brain and the gut, where the brain influences the digestive system and the gut can affect brain functions and behavior. This study postulates that probiotic supplementation has both preventive and therapeutic impacts on epilepsy through modulation of inflammatory responses and improvement of brain function.

MATERIALS AND METHODS

Male rats were gavaged with three probiotic strains (Lactobacillus reuteri, Bifidobacterium longum, Bifidobacterium lactis) daily for 28 days (10^9 CFU/mL) before inducing epilepsy with pentylenetetrazol (PTZ) injections (37.5 mg/kg every 48 h for 14 injections). Probiotic supplements were continued during disease induction. The effects of probiotics on seizure behavior, histopathology, and pro-inflammatory gene expression were assessed.

RESULTS

Probiotic consumption significantly reduced seizure severity, with evident effects from the fourth injection onwards (days 8-28). It delayed the onset of stage 2 and 5 seizures during kindling but had no major effect on stage 5 stability time. Histopathological analysis revealed amelioration of neuronal injury. Besides, there was a significant decrease in the expression of pro-inflammatory genes (Il-1β, Il-6, Ifng) and an increase in the expression of the anti-inflammatory Il-10 in the probiotic-treated model group.

CONCLUSION

Probiotics may have both preventive and therapeutic effects on PTZ-induced seizures through reduction of severity of seizures and modulating inflammatory responses. Additional studies are necessary to clarify the mechanisms, as treatment was given before and during kindling.

Heart rate variability, daily cortisol indices and their association with psychometric characteristics and gut microbiota composition in an Italian community sample

The microbiota-gut-brain axis is a complex communication system that plays a crucial role in influencing various aspects of our physical and mental health. The goal of this study was to determine the extent to which individual differences in resting measures of vagally-mediated heart rate variability (HRV) and cortisol levels were associated with psychometric and specific gut microbiota characteristics in seventy-five (38 females) healthy individuals. Participants were assessed for vagally-mediated HRV, daily salivary cortisol levels, psychometric characteristics, and gut microbiota composition. Using a categorical approach based on the median split of HRV and cortisol values, we identified an association between low vagally-mediated HRV, greater depressive symptomatology, and altered gut microbiota (e.g., a higher abundance of Prevotella and a smaller abundance of Faecalibacterium, Alistipes, and Gemmiger). This suggests that vagally-mediated HRV may be a useful biomarker of microbiota-gut brain axis function, and that low vagally-mediated HRV may play an important role in the bidirectional link between gut dysbiosis and depression. On the other hand, daily cortisol parameters (e.g., cortisol awakening response, diurnal cortisol slope) were associated either with higher anxiety and perceived stress, or with a specific gut microbiota profile. Therefore, their utility as biomarkers of microbiota-gut-brain axis function needs further scrutiny.

The Impact of Gut Microbiota on the Development of Anxiety Symptoms-A Narrative Review

The gut microbiota plays a key role in mental health, with growing evidence linking its composition to anxiety and depressive disorders. Research on this topic has expanded significantly in recent years. This review explores alterations in the gut microbiota of individuals with anxiety disorders and examines the potential therapeutic effects of probiotics. Background/Objectives: This review aims to analyze the alterations in gut microbiota composition in individuals with anxiety disorders and evaluate the potential therapeutic effects of probiotics in mitigating symptoms. By examining recent research, this study seeks to highlight the gut-brain connection and its implications for mental health interventions. Materials and Methods: A literature search was conducted in PubMed, Embase, CINAHL, and Google Scholar, focusing on studies investigating the relationship between gut microbiota and anxiety disorders, as well as the impact of probiotics on symptom severity. Results: The reviewed studies suggest that individuals with anxiety disorders often exhibit gut microbiota alterations, including reduced microbial diversity and a lower abundance of short-chain fatty acid-producing bacteria. Additionally, probiotics, particularly those from the Lactobacillus genus, may help alleviate anxiety symptoms by modulating gut microbiota composition. Conclusions: Gut dysbiosis appears to be closely linked to anxiety disorders, and probiotic interventions could represent a promising therapeutic avenue. However, further research is needed to clarify underlying mechanisms and optimize treatment strategies.

Psychobiotics Ameliorate Depression and Anxiety Status in Surgical Oncology Patients: Results from the ProDeCa Study

Background: Psychological disorders are prevalent in patients having undergone gastrointestinal cancer surgery, and their emotional status may further deteriorate during subsequent chemotherapy. Psychobiotics are specific probiotics that have the unique characteristics of producing neuroactive substances that are thought to act on the brain-gut axis. The aim of the present study was to evaluate the benefits of a psychobiotic formula on depression and anxiety status, as well as on perceived stress, versus a placebo in patients on a chemotherapy course following gastrointestinal surgery for cancer. Patients: The enrolled patients, allocated to the psychobiotic and placebo groups, were assessed by means of these psychometric tests: Beck's Depression Inventory and the Hamilton Depression Rating 17-item Scale for depression; the General Anxiety Disorder-7 for anxiety; and the Perceived Stress Scale-14 Item for perceived stress at three time-points: upon allocation [T1], after one month of treatment [T2], and two months thereafter [T3]. Results: In total, 266 patients were included. One month of psychobiotic treatment improved [i] depression status by 60.4% [48 depressed patients at T1, reduced to 16 at T3]; [ii] anxiety by 57.0% [72 patients at T1, 26 at T3]; and [iii] stress by 60.4% [42 at T1, 14 at T3]. The placebo-treated patients experienced a deterioration in all parameters studied, i.e., depression increased by 62.9%, anxiety by 39.7%, and stress by 142.5%. Conclusions: Based on these findings, it can be recognized that psychobiotic treatment has great potential for every patient at risk of suffering from depression, anxiety, or stress during the course of surgery/chemotherapy for gastrointestinal cancer.

Exploring the microbiota-gut-brain axis: impact on brain structure and function

The microbiota-gut-brain axis (MGBA) plays a significant role in the maintenance of brain structure and function. The MGBA serves as a conduit between the CNS and the ENS, facilitating communication between the emotional and cognitive centers of the brain via diverse pathways. In the initial stages of this review, we will examine the way how MGBA affects neurogenesis, neuronal dendritic morphology, axonal myelination, microglia structure, brain blood barrier (BBB) structure and permeability, and synaptic structure. Furthermore, we will review the potential mechanistic pathways of neuroplasticity through MGBA influence. The short-chain fatty acids (SCFAs) play a pivotal role in the MGBA, where they can modify the BBB. We will therefore discuss how SCFAs can influence microglia, neuronal, and astrocyte function, as well as their role in brain disorders such as Alzheimer's disease (AD), and Parkinson's disease (PD). Subsequently, we will examine the technical strategies employed to study MGBA interactions, including using germ-free (GF) animals, probiotics, fecal microbiota transplantation (FMT), and antibiotics-induced dysbiosis. Finally, we will examine how particular bacterial strains can affect brain structure and function. By gaining a deeper understanding of the MGBA, it may be possible to facilitate research into microbial-based pharmacological interventions and therapeutic strategies for neurological diseases.

The effect of probiotic-fortified kefir on depression, appetite, oxidative stress, and inflammatory parameters in Iranian overweight and obese elderly: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

It has been shown that the microflora of the gastrointestinal tract undergoes changes in obese individuals. The present study aimed to investigate the effect of kefir fortified with two strains, Lactobacillus helveticus and Bifidobacterium longum, on depression, appetite, oxidative stress, and inflammatory parameters in overweight and obese elderly individuals.

METHODS

This study was a double-blind, randomized, and placebo-controlled clinical trial conducted on 67 elderly men aged over 65, who were randomly divided into two groups. One group (n = 35) received one bottle (240 cc) of regular kefir as a placebo, while the intervention group (n = 32) received one bottle of probiotic-fortified kefir for eight weeks. Depression and appetite were evaluated using the Geriatric Depression Scale-15 (GDS-15) and a validated Visual Analogue Scale (VAS), respectively. Oxidative stress parameters were assessed using the standard calorimetric method, and inflammatory parameters were measured via the enzyme-linked immunosorbent assay method (ELISA). The differences between the two groups were compared using the independent samples T-test.

RESULTS

The median age of participant in both groups was 65 years. A significant difference in depression scores and the mean change between the two groups was observed after eight weeks (p = 0.001 and p = 0.042, respectively). Within-group comparison revealed a significant increase in appetite scores in both groups (p < 0.05 for both). Moreover, a significant difference in the changes in total antioxidant capacity (TAC) was noted (p = 0.009). However, no significant differences were observed in other oxidative and inflammatory parameters between the two groups (p˃0.05 for all).

CONCLUSIONS

The results demonstrated the positive impact of two specific strains of Bifidobacterium and Lactobacillus on improving depression in the elderly. However, when comparing the two groups, no significant effects were observed on appetite, inflammation, and oxidative stress parameters, except for TAC.

Unlocking the secrets of the human gut microbiota: Comprehensive review on its role in different diseases

The human gut microbiota, a complex and diverse community of microorganisms, plays a crucial role in maintaining overall health by influencing various physiological processes, including digestion, immune function, and disease susceptibility. The balance between beneficial and harmful bacteria is essential for health, with dysbiosis - disruption of this balance - linked to numerous conditions such as metabolic disorders, autoimmune diseases, and cancers. This review highlights key genera such as Enterococcus, Ruminococcus, Bacteroides, Bifidobacterium, Escherichia coli, Akkermansia muciniphila, Firmicutes (including Clostridium and Lactobacillus), and Roseburia due to their well-established roles in immune regulation and metabolic processes, but other bacteria, including Clostridioides difficile, Salmonella, Helicobacter pylori, and Fusobacterium nucleatum, are also implicated in dysbiosis and various diseases. Pathogenic bacteria, including Escherichia coli and Bacteroides fragilis, contribute to inflammation and cancer progression by disrupting immune responses and damaging tissues. The potential for microbiota-based therapies, such as probiotics, prebiotics, fecal microbiota transplantation, and dietary interventions, to improve health outcomes is examined. Future research directions in the integration of multi-omics, the impact of diet and lifestyle on microbiota composition, and advancing microbiota engineering techniques are also discussed. Understanding the gut microbiota's role in health and disease is essential for formulating personalized, efficacious treatments and preventive strategies, thereby enhancing health outcomes and progressing microbiome research.

Hypothalamus-pituitary-adrenal and gut-brain axes in biological interaction pathway of the depression

The hypothalamus-pituitary-adrenal (HPA) and gut-brain axes are vital biological pathways in depression. The HPA axis regulates the body's stress response, and chronic stress can lead to overactivation of the HPA axis, resulting in elevated cortisol levels that contribute to neuronal damage, particularly in regions such as the hippocampus and prefrontal cortex, both of which are involved in mood regulation and mental disorders. In parallel, the gut-brain axis, a bidirectional communication network between the gut microbiota and the central nervous system, influences emotional and cognitive functions. Imbalances in gut microbiota can affect the HPA axis, promoting inflammation and increasing gut permeability. This allows endotoxins to enter the bloodstream, contributing to neuroinflammation and altering neurotransmitter production, including serotonin. Since the majority of serotonin is produced in the gut, disruptions in this pathway may be linked to depressive symptoms. This review explores the interplay between the HPA axis and the gut-brain axis in the context of depression.

Multi-level analysis of gut microbiome extracellular vesicles-host interaction reveals a connection to gut-brain axis signaling

Microbiota-released extracellular vesicles (MEVs) have emerged as a key player in intercellular signaling. However, their involvement in the gut-brain axis has been poorly investigated. We hypothesize that MEVs cross host cellular barriers and deliver their cargoes of bioactive compounds to the brain. In this study, we aimed to investigate the cargo capacity of MEVs for bioactive metabolites and their interactions with the host cellular barriers. First, we conducted a multi-omics profiling of MEVs' contents from ex vivo and stool samples. Metabolomics analysis identified various neuro-related compounds encapsulated within MEVs, such as arachidonyl-dopamine, gabapentin, glutamate, and N-acylethanolamines. Metaproteomics unveiled an enrichment of enzymes involved in neuronal metabolism, primarily in the glutamine/glutamate/gamma-aminobutyric acid (GABA) pathway. These neuro-related proteins and metabolites were correlated with Bacteroides spp. We isolated 18 Bacteroides strains and assessed their GABA production capacity in extracellular vesicles (EVs) and culture supernatant. A GABA-producing Bacteroides finegoldii, released EVs with a high GABA content (4 µM) compared to Phocaeicola massiliensis. Upon testing the capacity of MEVs to cross host barriers, MEVs exhibited a dose-dependent paracellular transport and were endocytosed by Caco-2 and hCMEC/D3 cells. Exposure of Caco-2 cells to MEVs did not alter expression of genes related to intestinal barrier integrity, while affected immune pathways and cell apoptosis process as revealed by RNA-seq analyses. In vivo, MEVs biodistributed across mice organs, including the brain, liver, stomach, and spleen. Our results highlight the ability of MEVs to cross the intestinal and blood-brain barriers to deliver their cargoes to distant organs, with potential implication for the gut-brain axis.

IMPORTANCE

Microbiota-released extracellular vesicles (MEVs) have emerged as a key player in intercellular signaling. In this study, a multi-level analysis revealed presence of a diverse array of biologically active molecules encapsulated within MEVs, including neuroactive metabolites, such as arachidonyl-dopamine, gabapentin, glutamate, and N-acylethanolamines, and gamma-aminobutyric acid (GABA). Metaproteomics also unveiled an enrichment of neural-related proteins, mainly the glutamine/glutamate/GABA pathway. MEVs were able to cross epithelial and blood-brain barriers in vitro. RNA-seq analyses showed that MEVs stimulate several immune pathways while suppressing cell apoptosis process. Furthermore, MEVs were able to traverse the intestinal barriers and reach distal organs, including the brain, thereby potentially influencing brain functionality and contributing to mental and behavior.

Exploring the Multifaceted Therapeutic Potential of Probiotics: A Review of Current Insights and Applications

The interplay between human health and the microbiome has gained extensive attention, with probiotics emerging as pivotal therapeutic agents due to their vast potential in treating various health issues. As significant modulators of the gut microbiota, probiotics are crucial in maintaining intestinal homeostasis and enhancing the synthesis of short-chain fatty acids. Despite extensive research over the past decades, there remains an urgent need for a comprehensive and detailed review that encapsulates probiotics' latest insights and applications. This review focusses on the multifaceted roles of probiotics in promoting health and preventing disease, highlighting the complex mechanisms through which these beneficial bacteria influence both gut flora and the human body at large. This paper also explores probiotics' neurological and gastrointestinal applications, focussing on their significant impact on the gut-brain axis and their therapeutic potential in a broad spectrum of pathological conditions. Current innovations in probiotic formulations, mainly focusing on integrating genomics and biotechnological advancements, have also been comprehensively discussed herein. This paper also critically examines the regulatory landscape that governs probiotic use, ensuring safety and efficacy in clinical and dietary settings. By presenting a comprehensive overview of recent studies and emerging trends, this review aims to illuminate probiotics' extensive therapeutic capabilities, leading to future research and clinical applications. However, besides extensive research, further advanced explorations into probiotic interactions and mechanisms will be essential for developing more targeted and effective therapeutic strategies, potentially revolutionizing health care practices for consumers.

Exploring the complex relationship between psychosocial stress and the gut microbiome: implications for inflammation and immune modulation

There is growing interest in understanding the complex relationship between psychosocial stress and the human gastrointestinal microbiome (GIM). This review explores the potential physiological pathways connecting these two and how they contribute to a proinflammatory environment that can lead to the development and progression of the disease. Exposure to psychosocial stress triggers the activation of the sympathetic nervous system (SNS) and hypothalamic-pituitary axis (HPA), leading to various physiological responses essential for survival and coping with the stressor. However, chronic stress in susceptible individuals could cause sustained activation of HPA and SNS, leading to immune dysregulation consisting of redistribution of natural killer (NK) cells in the bloodstream, decreased function of T and B cells, and elevation of proinflammatory cytokines such as interleukin-1, interleukin-6, tumor necrotic factor-α, interferon-gamma. It also leads to disruption of the GIM composition and increased intestinal barrier permeability, contributing to GIM dysbiosis. The GIM dysbiosis and elevated cytokines can lead to reciprocal effects and further stimulate the HPA and SNS, creating a positive feedback loop that results in a proinflammatory state underlying the pathogenesis and progression of stress-associated cardiovascular, gastrointestinal, autoimmune, and psychiatric disorders. Understanding these relationships is critical for developing new strategies for managing stress-related health disorders.

Queuosine tRNA Modification: Connecting the Microbiome to the Translatome

Transfer RNA (tRNA) modifications play an important role in regulating mRNA translation at the codon level. tRNA modifications can influence codon selection and optimality, thus shifting translation toward specific sets of mRNAs in a dynamic manner. Queuosine (Q) is a tRNA modification occurring at the wobble position. In eukaryotes, queuosine is synthesized by the tRNA-guanine trans-glycosylase (TGT) complex, which incorporates the nucleobase queuine (or Qbase) into guanine of the GUN anticodons. Queuine is sourced from gut bacteria and dietary intake. Q was recently shown to be critical for cellular responses to oxidative and mitochondrial stresses, as well as its potential role in neurodegenerative diseases and brain health. These unique features of Q provide an interesting insight into the regulation of mRNA translation by gut bacteria, and the potential health implications. In this review, Q biology is examined in the light of recent literature and nearly 4 decades of research. Q's role in neuropsychiatric diseases and cancer is highlighted and discussed. Given the recent interest in Q, and the new findings, more research is needed to fully comprehend its biological function and disease relevance, especially in neurobiology.

Role of the gut microbiome in psychological symptoms associated with inflammatory bowel diseases

The brain-gut axis constitutes the basis for the bidirectional communication between the central nervous system and the gastrointestinal tract driven by neural, hormonal, metabolic, immunological, and microbial signals. Alterations in the gut microbiome composition as observed in inflammatory bowel diseases can modulate brain function and emerging empirical evidence has indicated that interactions among the brain-gut microbiome-axis seem to play a significant role in the pathogenesis of both inflammatory bowel diseases and psychiatric disorders and their comorbidity. Yet, the immunological and molecular mechanisms underlying the co-occurrence of inflammatory bowel diseases and psychological symptoms are still poorly understood. The aim of this narrative review is to highlight contemporary empirical findings supporting a pivotal role of the gut microbiome in the pathophysiology of highly prevalent neuropsychiatric symptoms in inflammatory bowel diseases such as fatigue, depression, and anxiety. Finally, we focus on microbiome modulation as potential treatment option for comorbid neuropsychiatric symptoms in immune-mediated diseases and especially in inflammatory bowel diseases. High-quality clinical trials are required to clarify how microbiome modulation through dietary interventions or probiotic, prebiotic or synbiotic treatment can be used clinically to improve mental health and thus quality of life of patients with inflammatory bowel diseases.

Efficacy and safety of gut microbiome-targeted treatment in patients with depression: a systematic review and meta-analysis

BACKGROUND

The study aimed to comprehensively analyze and establish a framework for evaluating the efficacy of microbiome-targeted treatment (MTT) for depression.

METHODS

We searched PubMed, Embase, Cochrane Library, Web of Science, and the Chinese National Knowledge Infrastructure database for randomized controlled trials (RCTs) on MTT in treating depression until October 19, 2023. A meta-analysis was conducted to evaluate the efficacy and safety of MTT. Comprehensive subgroup analyses were undertaken to explore factors influencing MTT's efficacy in treating depression. This study was registered with PROSPERO (CRD42023483649).

RESULTS

The study selection process identified 51,570 studies, of which 34 met the inclusion criteria. The overall pooled estimates showed that MTT significantly improved depression symptoms (SMD -0.26, 95% CI [-0.32, -0.19], I2 = 54%) with acceptable safety. Subgroup analyses by geography showed that effectiveness was demonstrated in Asia (SMD -0.46, 95% CI [-0.56, -0.36], I2 = 36%), while no evidence of effectiveness was found in Europe (SMD -0.07, 95% CI [-0.19, 0.05], I2 = 55%), America (SMD -0.33, 95% CI [-0.67, 0.02], I2 = 60%), and Oceania (SMD 0.00, 95% CI [-0.18, 0.18], I2 = 0%). Besides, the efficacy was shown in depressed patients without comorbidities (SMD -0.31, 95% CI [-0.40, -0.22], I2 = 0%), whereas effectiveness was poor in those with digestive disorders, such as irritable bowel syndrome (SMD -0.37, 95% CI [-0.89, 0.16], I2 = 74%), chronic diarrhea (SMD -0.34, 95% CI [-0.73, 0.05]), and chronic constipation (SMD -0.23, 95% CI [-0.57, 0.11], I2 = 0%). In perinatal depressed patients, MTT was not effective (SMD 0.16, 95% CI [0.01, 0.31], I2 = 0%). It was found that < 8 weeks (SMD -0.33, 95% CI [-0.45, -0.22], I2 = 0%) and 8-12 weeks (SMD -0.34, 95% CI [-0.44, -0.23], I2 = 57%) MTT were effective, while > 12 weeks (SMD 0.02, 95% CI [-0.12, 0.17], I2 = 68%) MTT was ineffective.

CONCLUSIONS

Despite the overall effectiveness of MTT in treating depression and its acceptable safety profile, caution is warranted in drawing this conclusion due to limitations posed by the small sample size of included studies and heterogeneity. The efficacy of MTT for depression exhibits variation influenced by geography, patient comorbidities, and duration of administration.

Age-Related Changes in Gut Health and Behavioral Biomarkers in a Beagle Dog Population

The gut and the gut microbiome communicate with the nervous system through the gut-brain axis via neuroimmune and neuroendocrine mechanisms. Despite existing research, studies exploring this link in aging dogs are limited. This study aims to examine multiple blood and fecal biomarkers of intestinal health, along with various behavioral indicators based on saliva, blood, observations, and activity, in different age populations (junior: <2 y.o.; adult: 2-7 y.o.; senior: >7 y.o.) of thirty-seven Beagle dogs. In our study, Bacteroides were significantly higher in senior dogs. The relative abundance of Faecalibacterium and Blautia showed age-related trends, higher in senior and junior dogs, respectively. Fecal short-chain fatty acid concentration, especially acetate, increased with age, while propionate was higher in junior dogs. For the behavioral indicators we considered, blood thyroxine concentration, playing, exploring, and total activity were higher in junior dogs. The differences observed between the biomarkers of gut health and behavior, particularly those significant for the age correlations, emphasize the importance of considering age-related factors when studying the gut microbiome and behavior. However, further research is needed to better understand the mechanisms and specific pathways involved in the relationship between the studied biomarkers and age.

Biological, environmental, and psychological stress and the human gut microbiome in healthy adults

Emerging research suggests that the gut microbiome plays a crucial role in stress. We assess stress-microbiome associations in two samples of healthy adults across three stress domains (perceived stress, stressful life events, and biological stress /Respiratory Sinus Arrhythmia; RSA). Study 1 (n = 62; mean-age = 37.3 years; 68% female) and Study 2 (n = 74; mean-age = 41.6 years; female only) measured RSA during laboratory stressors and used 16S rRNA pyrosequencing to classify gut microbial composition from fecal samples. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was used to predict functional pathways of metagenomes. Results showed differences in beta diversity between high and low stressful life events groups across both studies. Study 1 revealed differences in beta diversity between high and low RSA groups. In Study 1, the low perceived stress group was higher in alpha diversity than the high perceived stress group. Levels of Clostridium were negatively associated with RSA in Study 1 and levels Escherichia/Shigella were positively associated with perceived stress in Study 2. Associations between microbial functional pathways (L-lysine production and formaldehyde absorption) and RSA are discussed. Findings suggest that certain features of the gut microbiome are differentially associated with each stress domain.

Stress-induced VIPergic activation mediates microbiota/Th17cell-dependent depressive-like behaviors

Chronic stress often has deleterious effects leading to the development of psychiatric diseases. The gut-brain axis represents a novel avenue for stress research. The negative effects of stress on the gut physiology have been well-described, whereas the pathways whereby stress controls microbial composition to modulate behaviors remains mainly unknown. We discovered that vasoactive intestinal peptide (VIP) activation promoted stress-induced microbial changes leading to increased infiltration of T helper (Th) 17 cells and microglial activation in the hippocampus and depressive-like behaviors, uncovering a close crosstalk between intestinal VIPergic release and the gut microbiota during stress and providing a new interaction between the nervous system and the gut microbiome after stress. Neutralization of the signature cytokine of Th17 cells, interleukin (IL)-17A, was sufficient to block depressive-like behaviors, reduce neuronal VIPergic activation and microglia activation induced by VIPergic activation after stress, opening new potential therapeutic targets for depression.

The effect of exercise on depression and gut microbiota: Possible mechanisms

Exercise can effectively prevent and treat depression and anxiety, with gut microbiota playing a crucial role in this process. Studies have shown that exercise can influence the diversity and composition of gut microbiota, which in turn affects depression through immune, endocrine, and neural pathways in the gut-brain axis. The effectiveness of exercise varies based on its type, intensity, and duration, largely due to the different changes in gut microbiota. This article summarizes the possible mechanisms by which exercise affects gut microbiota and how gut microbiota influences depression. Additionally, we reviewed literature on the effects of exercise on depression at different intensities, types, and durations to provide a reference for future exercise-based therapies for depression.

The involvement of the microbiota-gut-brain axis in the pathophysiology of mood disorders and therapeutic implications

INTRODUCTION

There is a growing body of evidence implicating gut-brain axis dysfunction in the pathophysiology of mood disorders. Accordingly, gut microbiota has become a promising target for the development of biomarkers and novel therapeutics for bipolar and depressive disorders.

AREAS COVERED

We describe the observed changes in the gut microbiota of patients with mood disorders and discuss the available studies assessing microbiota-based strategies for their treatment.

EXPERT OPINION

Microbiota-targeted interventions, such as symbiotics, prebiotics, paraprobiotics, and fecal microbiota transplants seem to attenuate the severity of depressive symptoms. The available results must be seen as preliminary and need to be replicated and/or confirmed in larger and independent studies, also considering the pathophysiological and clinical heterogeneity of mood disorders.

Exploring Gut Microbiota Imbalance in Irritable Bowel Syndrome: Potential Therapeutic Effects of Probiotics and Their Metabolites

Irritable bowel syndrome is a common functional gastrointestinal disorder characterized by recurrent abdominal discomfort, bloating, cramping, flatulence, and changes in bowel movements. The pathophysiology of IBS involves a complex interaction between motor, sensory, microbiological, immunological, and psychological factors. Diversity, stability, and metabolic activity of the gut microbiota are frequently altered in IBS, thus leading to a situation of gut dysbiosis. Therefore, the use of probiotics and probiotic-derived metabolites may be helpful in balancing the gut microbiota and alleviating irritable bowel syndrome symptoms. This review aimed to report and consolidate recent progress in understanding the role of gut dysbiosis in the pathophysiology of IBS, as well as the current studies that have focused on the use of probiotics and their metabolites, providing a foundation for their potential beneficial effects as a complementary and alternative therapeutic strategy for this condition due to the current absence of effective and safe treatments.

Nutritional Strategies for Enhancing Performance and Training Adaptation in Weightlifters

Weightlifting demands explosive power and neuromuscular coordination in brief, repeated intervals. These physiological demands underscore the critical role of nutrition, not only in optimizing performance during competitions but also in supporting athletes' rigorous training adaptations and ensuring effective recovery between sessions. As weightlifters strive to enhance their performance, well-structured nutritional strategies are indispensable. In this comprehensive review, we explored how weightlifters can optimize their performance through targeted nutritional strategies, including carbohydrate intake for glycogen replenishment and proteins for muscle growth and recovery. Additionally, the roles of key supplements, such as creatine, beta-alanine, and branch-chained amino acids in enhancing strength, delaying fatigue, and supporting muscle repair were discussed. A comprehensive literature review was conducted using PubMed, Google Scholar, and Web of Science to gather studies on nutritional strategies for weightlifting performance and training adaptation. The review focused on English-language articles relevant to weightlifters, including studies on powerlifting, while excluding those involving non-human subjects. Weightlifting requires explosive power, and proper nutrition is vital for performance and recovery, emphasizing the role of carbohydrate, protein, and fat intake. Nutrient timing and personalized strategies, informed by genetic and metabolomic analyses, enhance recovery and performance, while supplements like creatine, caffeine, and beta-alanine can significantly improve results when used correctly. Sustainable nutritional strategies are essential for enhancing weightlifter performance, emphasizing a balanced approach over extreme diets or excessive supplements. Further research is needed to refine these strategies based on individual athlete characteristics, ensuring consistent top-level performance throughout competitive seasons.

Ameliorating effect of psychobiotics and para-psychobiotics on stress: A review on in vivo and clinical studies and mechanism of action

Chronic stress can negatively affect cognitive ability, behavioral functions, and gut microbiota balance. The gut microbiota communicates with the brain through the gut-brain axis to influence brain responses and behavior. The positive effects of psychobiotics and para-psychobiotics (viable and non-viable probiotics, respectively) on decreasing stress and stress-related disorders have been approved, previously. It has been suggested that the benefits of such probiotics are provided through different probable routes including the hypothalamic-pituitary-adrenal (HPA) axis, the immune system modulation, and the production of neurotransmitters. The recent review aims to explore the different potentials of psychobiotics and para-psychobiotics based on recent literature. The recent literature revealed that psychobiotics and para-psychobiotics could be considered as an alternative to psychotropic drugs which present dependence and side effects compared to chemical drugs.

Psychological stressors involved in the pathogenesis of premature ovarian insufficiency and potential intervention measures

Premature ovarian insufficiency (POI) is a common gynecological endocrine disease, which seriously affects women's physical and mental health and fertility, and its incidence is increasing year by year. With the development of social economy and technology, psychological stressors such as anxiety and depression caused by social, life and environmental factors may be one of the risk factors for POI. We used PubMed to search peer-reviewed original English manuscripts published over the last 10 years to identify established and experimental studies on the relationship between various types of stress and decreased ovarian function. Oxidative stress, follicular atresia, and excessive activation of oocytes, caused by Stress-associated factors may be the main causes of ovarian function damage. This article reviews the relationship between psychological stressors and hypoovarian function and the possible early intervention measures in order to provide new ideas for future clinical treatment and intervention.

Impact of Probiotics and Prebiotics on Gut Microbiome and Hormonal Regulation

The gut microbiome plays a crucial role in human health by influencing various physiological functions through complex interactions with the endocrine system. These interactions involve the production of metabolites, signaling molecules, and direct communication with endocrine cells, which modulate hormone secretion and activity. As a result, the microbiome can exert neuroendocrine effects and contribute to metabolic regulation, adiposity, and appetite control. Additionally, the gut microbiome influences reproductive health by altering levels of sex hormones such as estrogen and testosterone, potentially contributing to conditions like polycystic ovary syndrome (PCOS) and hypogonadism. Given these roles, targeting the gut microbiome offers researchers and clinicians novel opportunities to improve overall health and well-being. Probiotics, such as Lactobacillus and Bifidobacterium, are live beneficial microbes that help maintain gut health by balancing the microbiota. Prebiotics, non-digestible fibers, nourish these beneficial bacteria, promoting their growth and activity. When combined, probiotics and prebiotics form synbiotics, which work synergistically to enhance the gut microbiota balance and improve metabolic, immune, and hormonal health. This integrated approach shows promising potential for managing conditions related to hormonal imbalances, though further research is needed to fully understand their specific mechanisms and therapeutic potential.

Adult neurogenesis and the microbiota-gut-brain axis in farm animals: underestimated and understudied parameters for improving welfare in livestock farming

Welfare in commercial livestock farming is becoming increasingly important in current agriculture research. Unfortunately, there is a lack of understanding about the neuronal mechanisms that underlie well-being on an individual level. Neuroplasticity in the hippocampus, the subventricular zone (SVZ), the olfactory bulb (OB) and the hypothalamus may be essential regulatory components in the context of farm animal behaviour and welfare that may be altered by providing environmental enrichment (EE). The importance of pre-and probiotics as a form of EE and the microbiota-gut-brain axis (MGBA) has come under the spotlight in the last 20 years, particularly in the contexts of research into stress and of stress resilience. However, it could also be an important regulatory system for animal welfare in livestock farming. This review aims to present a brief overview of the effects of EE on physiology and behaviour in farm animals and briefly discusses literature on behavioural flexibility, as well as inter-individual stress-coping styles and their relationship to animal welfare. Most importantly, we will summarise the literature on different forms of neural plasticity in farm animals, focusing on neurogenesis in various relevant brain regions. Furthermore, we will provide a brief outlook connecting these forms of neuroplasticity, stress, EE, the MGBA and welfare measures in modern livestock farming, concentrating on pigs.

The impact of a prebiotic-rich diet and/or probiotic supplements on human cognition: Secondary outcomes from the 'Gut Feelings' randomised controlled trial

BACKGROUND

Emerging evidence indicates that gut microbiota-targeted interventions may lead to improvements in cognition. We assessed whether a prebiotic-rich dietary intervention, probiotic supplement, or synbiotic combination of both would improve human cognition, as part of the 'Gut Feelings' trial.

METHODS

An 8-week, 2 × 2 factorial randomised controlled trial was conducted on 118 adults with low mood and potential for dietary improvement. Treatment arms: (1) probiotic supplement and diet-as-usual (probiotic group); (2) high-prebiotic diet and placebo supplement (prebiotic diet group); (3) probiotic supplement and high-prebiotic diet (synbiotic group); and (4) placebo supplement and diet-as-usual (placebo group). At baseline and 8-weeks, the Cogstate Brief Battery was administered, testing processing speed, attention, visual learning, and working memory. Data were analysed using Bayesian linear regression.

RESULTS

We found weak evidence that the probiotic improved working memory (Cohen's d = -0.32, 95% CI: -0.67, 0.03; posterior probability [post. prob] of benefit: 96%). For the other treatments, there was little or no evidence of cognitive improvement. We found weak evidence that the prebiotic diet impaired processing speed (d = 0.25, 95% CI: -0.02, 0.51; post. prob of harm: 97%). There was little indication of a synergistic interaction between the probiotic and prebiotic diet.

CONCLUSION

We found suggestive evidence of a probiotic-induced improvement in working memory, and prebiotic-induced impairment in processing speed. However, the evidence remains inconclusive regarding any cognitive benefit or harm induced by the probiotic, prebiotic diet, or synbiotic treatments. Larger intervention studies are recommended, with inclusion of neuroimaging or electrophysiology measures.Trial Registration: Australian New Zealand Clinical Trials Registry (ACTRN12617000795392; registered 31 May 2017).

Lactobacillus Helveticus Improves Controlled Cortical Impact Injury-Generated Neurological Aberrations by Remodeling of Gut-Brain Axis Mediators

Considerable studies augured the potential of gut microbiota-based interventions in brain injury-associated complications. Based on our earlier study results, we envisaged the sex-specific neuroprotective effect of Lactobacillus helveticus by remodeling of gut-brain axis. In this study, we investigated the effect of L. helveticus on neurological complications in a mouse model of controlled cortical impact (CCI). Adult, male and female, C57BL/6 mice underwent CCI surgery and received L. helveticus treatment for six weeks. Sensorimotor function was evaluated via neurological severity score and rotarod test. Long-term effects on anxiety-like behavior and cognition were assessed using the elevated-zero maze (EZM) and novel object recognition test (NORT). Brain perilesional area, blood, colon, and fecal samples were collected post-CCI for molecular biology analysis. CCI-operated mice displayed significant neurological impairments at 1-, 3-, 5-, and 7-days post-injury (dpi) and exhibited altered behavior in EZM and NORT compared to sham-operated mice. However, these behavioral changes were ameliorated in mice receiving L. helveticus. GFAP, Iba-1, TNF-α, and IL-1β expressions and corticotrophin-releasing hormone (CRH) levels were elevated in the perilesional cortex of CCI-operated male/female mice. These elevated biomarkers and decreased BDNF levels in both male/female mice were modified by L. helveticus treatment. Additionally, L. helveticus treatment restored altered short-chain fatty acids (SCFAs) levels in fecal samples and improved intestinal integrity but did not affect decreased plasma levels of progesterone and testosterone in CCI mice. These results indicate that L. helveticus exerts beneficial effects in the CCI mouse model by mitigating inflammation and remodeling of gut microbiota-brain mediators.

Underneath the Gut-Brain Axis in IBD-Evidence of the Non-Obvious

The gut-brain axis (GBA) plays a pivotal role in human health and wellness by orchestrating complex bidirectional regulation and influencing numerous critical processes within the body. Over the past decade, research has increasingly focused on the GBA in the context of inflammatory bowel disease (IBD). Beyond its well-documented effects on the GBA-enteric nervous system and vagus nerve dysregulation, and gut microbiota misbalance-IBD also leads to impairments in the metabolic and cellular functions: metabolic dysregulation, mitochondrial dysfunction, cationic transport, and cytoskeleton dysregulation. These systemic effects are currently underexplored in relation to the GBA; however, they are crucial for the nervous system cells' functioning. This review summarizes the studies on the particular mechanisms of metabolic dysregulation, mitochondrial dysfunction, cationic transport, and cytoskeleton impairments in IBD. Understanding the involvement of these processes in the GBA may help find new therapeutic targets and develop systemic approaches to improve the quality of life in IBD patients.

Functional yogurt: a comprehensive review of its nutritional composition and health benefits

Functional yogurt, renowned for its enhanced nutritional profile and potential health benefits, has emerged as a promising functional food. This review meticulously examines the nutritional composition of functional yogurt, highlighting its enriched content of probiotics, prebiotics, synbiotics, antioxidants, vitamins, minerals, proteins, and other bioactive compounds, which contribute to its health-promoting properties. Functional yogurt has positively affected digestive health, immune function, metabolic health, and mental well-being. It benefits digestive health by alleviating diarrhoeal symptoms, constipation, colon cancer, irritable bowel syndrome (IBS), Helicobacter pylori infection, and digestive-related allergies. Moreover, the immune-boosting properties of functional yogurt play a pivotal role in reducing the risk of infections and inflammation. In addition, functional yogurt has the potential to improve metabolic health, leading to decreased cholesterol levels and enhanced blood sugar regulation. Emerging research also suggests functional yogurt may positively influence mood, behavior, and cognitive function. Functional yogurt is a valuable addition to the human diet, holding significant implications for public health. In addition to its numerous health benefits, functional yogurt also faces limitations, such as the stability of functional compounds, sensory alterations, potential digestive discomfort, and inconsistent efficacy across populations, highlighting the need for further research and optimization.

Exploring the impact of probiotics on adult ADHD management through a double-blind RCT

Attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric condition often persisting into adulthood, characterized by inattention, impulsivity, and hyperactivity. Emerging research suggests a connection between ADHD and gut microbiota, highlighting probiotics as potential therapeutic agents. This study involved a double-blind, randomized controlled trial where college students with ADHD received either a multi-strain probiotic supplement or a placebo daily for three months. ADHD symptoms were evaluated using a computerized performance test (MOXO) and the MATAL questionnaire. Academic records provided performance data. Additionally, eating and sleeping habits, gastrointestinal symptoms, and anthropometrics were assessed through questionnaires before and after the intervention. Fingernail cortisol concentrations (FCC) measured the long-term activity of the hypothalamic-pituitary-adrenal axis. The findings indicated that the probiotic significantly decreased hyperactivity, improved gastrointestinal symptoms, and enhanced academic performance. A multivariate analysis identified age as a significant predictor, with younger participants experiencing greater overall benefits from the intervention. There was also a negative correlation between FCC and symptoms of attention and impulsivity. Furthermore, higher academic grades were associated with lower levels of hyperactivity and impulsivity. These results suggest a beneficial impact of probiotics on ADHD symptoms and lay the groundwork for further studies to evaluate the effects of various probiotic strains on clinical outcomes in ADHD.

Lactobacillus rhamnosus GG attenuates depression-like behaviour and cognitive deficits in chronic ethanol exposure mice by down-regulating systemic inflammatory factors

Ethanol can directly or indirectly lead to cognitive and mental disorders. The long-term intake of alcohol can directly affect the distribution of gut microbiota. Lactobacillus rhamnosus GG (LGG) is a natural bacterium isolated from healthy human intestines that has the function of preventing cytokine-induced cell apoptosis and protecting cell barriers. However, the regulatory effect of LGG on cognitive and mental disorders caused by chronic ethanol exposure (CEE) is still unclear. In this study, we established a CEE mouse model through free alcohol consumption and added LGG or antibiotics in the later stages of the model. Sequencing analysis of the 16S rRNA gene showed that CEE resulted in a decrease in the abundance and diversity of mouse gut microbial communities accompanied by alterations in the relative abundance of multiple enterobacterial genera. The use of LGG and antibiotics alleviated the depression-like behaviour and cognitive impairment of CEE-induced mice, reduced expression of inflammatory factors such as interleukin (IL)-6, IL-1β and tumour necrosis factor (TNF)-α in the ileum, serum and brain and increased the expression of synaptophysin (SYN), postsynaptic density protein-95 (PSD-95) and brain-derived neurotrophic factor (BDNF) in the hippocampus. Together, LGG can alleviate depression-like behaviour caused by CEE in mice while also improving cognitive and memory functions through reducing peripheral and nervous system inflammation factors and balancing gut microbiota.

Pharmacists' Knowledge, Perception, and Prescribing Practice of Probiotics in the UAE: A Cross-Sectional Study

BACKGROUND

The human body is a complex and interconnected system where trillions of microorganisms, collectively known as the gut microbiota, coexist with these cells. Besides maintaining digestive health, this relationship also impacts well-being, including immune function, metabolism, and mental health. As frontline healthcare providers, pharmacists are pivotal in promoting the benefits of probiotics for immune support. This study explored pharmacists' knowledge, perception, and practice behavior in the UAE towards the implication of probiotic application beyond digestive health, such as cardiovascular and mental health impacts and their diverse dosage forms.

METHOD

An online self-administered survey was distributed among pharmacists in the UAE. Data were collected through personal visits to pharmacies, where pharmacists were approached and asked to complete the questionnaire. The sample size included 407 pharmacists, determined using the formula for proportions with a 95% confidence level and a 5% margin of error. Statistical analysis was performed using SPSS version 29. Descriptive statistics were used to summarize demographic characteristics and survey responses. The knowledge levels were categorized into poor, moderate, and good. Chi-square analysis was employed to investigate associations between demographic factors and knowledge levels, with a significance level set at p < 0.05, enhancing the robustness of the study's findings.

RESULTS

This study included 407 completed eligible responses. About 63.56% of participants were female, with 52.1% employed in pharmacy chains. While 91.2% of pharmacists recognized probiotics' role in immune support, only 30% were aware of their cardiovascular benefits. Moreover, chewing gum was the least known dosage form of probiotics, recognized by only 16.7% of respondents. Additionally, only 57% of the participants recognized liposomes as a dosage form. In practice, most pharmacists recommended storing probiotics at room temperature, accounting for 66.6%. The most prevalent misconception encountered in the pharmacy setting was the belief that probiotics are primarily intended for gastrointestinal tract problems, at 79.1% of the respondents. Regarding perception, the agreement was observed regarding the safety of probiotics for all ages. Perceived barriers included the high cost of probiotics, with the majority (86.5%) indicating this as a significant obstacle, while lack of demand was identified as the minor barrier by 64.6%. Additionally, an association was found at a significance level of p < 0.05 with knowledge, gender, educational level, type and location of pharmacy, and source of information.

CONCLUSIONS

The study highlights knowledge gaps in pharmacists' understanding of probiotic applications beyond digestive health, particularly cardiovascular health and depression. Targeted educational interventions are necessary to address these gaps. The findings underscore the importance of ongoing professional development for pharmacists, enhancing their role in patient education and the promotion of probiotics for overall health.

Synbiotic supplementation may globally improve non-motor symptoms in patients with stable Parkinson's disease: results from an open label single-arm study

Gut microbiota changes and brain-gut-axis (BGA) dysregulation are common in people with Parkinson's Disease (PD). Probiotics and prebiotics are emerging as a potential therapeutic approach for PD patients. The aim of this paper was to assess the neurological and gastroenterological effects in PD patients with constipation after the administration of a synbiotic product, with a focus on behavioral and cognitive symptoms. We enrolled patients with stable PD who met diagnostic criteria for functional constipation and/or irritable bowel syndrome with constipation according to Rome IV Criteria. Patients received a synbiotic treatment (Enterolactis Duo, containing the probiotic strain Lacticaseibacillus paracasei DG and the prebiotic fiber inulin) for 12 weeks. A neurological and a gastroenterological evaluation were collected before and after the treatment. In addition, 16S rRNA gene profiling and short chain fatty acid quantification were performed to characterize the microbial ecosystem of fecal samples collected before (n = 22) and after (n = 9) the synbiotic administration. 30 patients were consecutively enrolled. After treatment, patients performed better in MDS-UPDRS part 1 (p = 0.000), SCOPA-AUT (p = 0.001), TAS-20 (p = 0.014), HAM-D (p = 0.026), DIFt (p = 0.003), PAS-A (p = 0.048). Gastroenterological evaluations showed improvements in PAC-SYM score (p < 0.001), number of complete bowel movement (p < 0.001) and BSFS (p < 0.001). After the synbiotic administration, we observed a significant increase in the abundance of the order Oscillospirales, as well as the Oscillospiraceae family and the species Faecalibacterium prausnitzii within this order in fecal samples. Synbiotic treatment demonstrates potential efficacy in ameliorating non-motor features in PD patients.

The Role of Gastrointestinal Dysbiosis and Fecal Transplantation in Various Neurocognitive Disorders

This review explores the critical role of the human microbiome in neurological and neurodegenerative disorders, focusing on gut-brain axis dysfunction caused by dysbiosis, an imbalance in gut bacteria. Dysbiosis has been linked to diseases such as Alzheimer's disease, Parkinson's disease (PD), multiple sclerosis (MS), and stroke. The gut microbiome influences the central nervous system (CNS) through signaling molecules, including short-chain fatty acids, neurotransmitters, and metabolites, impacting brain health and disease progression. Emerging therapies, such as fecal microbiota transplantation (FMT), have shown promise in restoring microbial balance and alleviating neurological symptoms, especially in Alzheimer's and PD. Additionally, nutritional interventions such as probiotics, prebiotics, and specialized diets are being investigated for their ability to modify gut microbiota and improve patient outcomes. This review highlights the therapeutic potential of gut microbiota modulation but emphasizes the need for further clinical trials to establish the safety and efficacy of these interventions in neurological and mental health disorders.

The Efficacy of Probiotics Supplementation on the Quality of Life of Patients with Gastrointestinal Disease: A Systematic Review of Clinical Studies

Patients with gastrointestinal (GI) disorders might benefit from probiotic supplementation to resolve their bowel symptoms and enhance their quality of life (QoL). This systematic review aimed to evaluate the effects of oral probiotic supplementation on improving QoL. Relevant studies were systematically searched in online databases, including PubMed, Scopus, Embase, ProQuest, and Google Scholar up to September 2022 using relevant keywords. Studies that were conducted on GI patients and presented QoL outcomes were included. The Revised Cochrane Risk of Bias 2 tool and the Risk Of Bias In Non-randomized Studies of Intervention tool were used to assess the risk of bias. Of the 4,555 results found in the systematic search of databases, only 36 studies were eligible for evaluation. According to this systematic review, 24 studies reported improvements, whereas 12 studies reported no improvements on QoL in GI patients supplemented with probiotics. We found that probiotics may improve the QoL of patients with GI diseases and related metabolic complications. Therefore, probiotics can be a useful supportive treatment strategy in these patients.

The major biogenic amine metabolites in mood disorders

Mood disorders, including major depressive disorder and bipolar disorder, have a profound impact on more than 300 million people worldwide. It has been demonstrated mood disorders were closely associated with deviations in biogenic amine metabolites, which are involved in numerous critical physiological processes. The peripheral and central alteration of biogenic amine metabolites in patients may be one of the potential pathogeneses of mood disorders. This review provides a concise overview of the latest research on biogenic amine metabolites in mood disorders, such as histamine, kynurenine, and creatine. Further studies need larger sample sizes and multi-center collaboration. Investigating the changes of biogenic amine metabolites in mood disorders can provide biological foundation for diagnosis, offer guidance for more potent treatments, and aid in elucidating the biological mechanisms underlying mood disorders.

Cutting-Edge iPSC-Based Approaches in Studying Host-Microbe Interactions in Neuropsychiatric Disorders

Gut microbiota (GM), together with its metabolites (such as SCFA, tryptophan, dopamine, GABA, etc.), plays an important role in the functioning of the central nervous system. Various neurological and psychiatric disorders are associated with changes in the composition of GM and their metabolites, which puts them in the foreground as a potential adjuvant therapy. However, the molecular mechanisms behind this relationship are not clear enough. Therefore, before considering beneficial microbes and/or their metabolites as potential therapeutics for brain disorders, the mechanisms underlying microbiota-host interactions must be identified and characterized in detail. In this review, we summarize the current knowledge of GM alterations observed in prevalent neurological and psychiatric disorders, multiple sclerosis, major depressive disorder, Alzheimer's disease, and autism spectrum disorders, together with experimental evidence of their potential to improve patients' quality of life. We further discuss the main obstacles in the study of GM-host interactions and describe the state-of-the-art solution and trends in this field, namely "culturomics" which enables the culture and identification of novel bacteria that inhabit the human gut, and models of the gut and blood-brain barrier as well as the gut-brain axis based on induced pluripotent stem cells (iPSCs) and iPSC derivatives, thus pursuing a personalized medicine agenda for neuropsychiatric disorders.

Possible application of Akkermansia muciniphila in stress management

Akkermansia muciniphila (A. muciniphila) is a promising candidate bacterium for stress management due to its beneficial effects on the microbiota-gut-brain axis (MGBA). As a well-known mucin-degrading bacterium in the digestive tract, A. muciniphila has demonstrated significant benefits for host physiology. Recent research highlights its potential in treating several neuropsychiatric disorders. Proposed mechanisms of action include the bacterium's outer membrane protein Amuc_1100 and potentially its extracellular vesicles (EVs), which interact with host immune receptors and influence serotonin pathways, which are crucial for emotional regulation. Despite its potential, the administration of probiotics containing A. muciniphila faces technological challenges, prompting the development of pasteurized forms recognized as safe by the European Food Safety Authority (EFSA). This review systematically examines the existing literature on the role of A. muciniphila in stress management, emphasizing the need for further research to validate its efficacy. The review follows a structured methodology, including comprehensive database searches and thematic data analysis, to provide a detailed understanding of the relationship between stress, microbiota, and A. muciniphila therapeutic potential.

Effects of Probiotic Supplementation Added to a Weight Loss Program on Anthropometric Measures, Body Composition, Eating Behavior, and Related Hormone Levels in Patients with Food Addiction and Weight Regain After Bariatric Surgery: A Randomized Clinical Trial

PURPOSE

Weight regain after metabolic bariatric surgery is a common problem. Food addiction is an eating disorder that can be one of the reasons for weight regain in these patients. This study aimed to evaluate the effects of probiotic supplementation with a weight loss program and cognitive behavioral therapy (CBT) on anthropometric measures, eating behavior, food addiction, and related hormone levels, in patients with food addiction and weight regain after metabolic bariatric surgery.

MATERIALS AND METHODS

This randomized, triple-blind, placebo-controlled clinical trial was conducted on patients with food addiction and weight regain after metabolic bariatric surgery. Participants (n = 50) received a weight loss program and CBT plus probiotic, or placebo for 12 weeks. Then, anthropometric measurements, biochemical markers, eating behavior, and food addiction were assessed.

RESULTS

Weight and body mass index (BMI) decreased significantly in the probiotic group compared to placebo (p = 0.008, p = 0.001, respectively). Fat mass was significantly decreased in the probiotic group (p < 0.001). Moreover, a significant improvement was observed in the probiotic group's eating behavior and food addiction compared to the placebo group (p < 0.001). Serum levels of leptin decreased significantly (p = 0.02), and oxytocin serum levels increased significantly (p = 0.008) in the probiotic group compared to the placebo group.

CONCLUSION

Adding probiotic supplements to the weight loss program and CBT is superior to the weight loss program and CBT alone in improving weight loss, eating behavior, and food addiction in patients with food addiction and weight regain after metabolic bariatric surgery.

Exploring the pathogenesis and treatment of PSD from the perspective of gut microbiota

Post-stroke depression (PSD) is a psychological disease that can occur following a stroke and is associated with serious consequences. Research on the pathogenesis and treatment of PSD is still in the infancy stage. Patients with PSD often exhibit gastrointestinal symptoms; therefore the role of gut microbiota in the pathophysiology and potential treatment effects of PSD has become a hot topic of research. In this review, describe the research on the pathogenesis and therapy of PSD. We also describe how the gut microbiota influences neurotransmitters, the endocrine system, energy metabolism, and the immune system. It was proposed that the gut microbiota is involved in the pathogenesis and treatment of PSD through the regulation of neurotransmitter levels, vagal signaling, hypothalamic-pituitary-adrenal axis activation and inhibition, hormone secretion and release, in addition to immunity and inflammation.

"Inflamed" depression: A review of the interactions between depression and inflammation and current anti-inflammatory strategies for depression

Depression is a common mental disorder, the effective treatment of which remains a challenging issue worldwide. The clinical pathogenesis of depression has been deeply explored, leading to the formulation of various pathogenic hypotheses. Among these, the monoamine neurotransmitter hypothesis holds a prominent position, yet it has significant limitations as more than one-third of patients do not respond to conventional treatments targeting monoamine transmission disturbances. Over the past few decades, a growing body of research has highlighted the link between inflammation and depression as a potential key factor in the pathophysiology of depression. In this review, we first summarize the relationship between inflammation and depression, with a focus on the pathophysiological changes mediated by inflammation in depression. The mechanisms linking inflammation to depression as well as multiple anti-inflammatory strategies are also discussed, and their efficacy and safety are assessed. This review broadens the perspective on specific aspects of using anti-inflammatory strategies for treating depression, laying the groundwork for advancing precision medicine for individuals suffering from "inflamed" depression.

Exploring the gut-brain Axis: Potential therapeutic impact of Psychobiotics on mental health

One of the most challenging and controversial issues in microbiome research is related to gut microbial metabolism and neuropsychological disorders. Psychobiotics affect human behavior and central nervous system processes via the gut-brain axis, involving neuronal, immune, and metabolic pathways. They have therapeutic potential in the treatment of several neurodegenerative and neurodevelopmental disorders such as depression, anxiety, autism, attention deficit hyperactivity disorder, Alzheimer's disease, Parkinson's disease, schizophrenia, Huntington's disease, anorexia nervosa, and multiple sclerosis. However, the mechanisms underlying the interaction between psychobiotics and the abovementioned diseases need further exploration. This review focuses on the relationship between gut microbiota and its impact on neurological and neurodegenerative disorders, examining the potential of psychobiotics as a preventive and therapeutic approach, summarising recent research on the gut-brain axis and the potential beneficial effects of psychobiotics, highlighting the need for further research and investigation in this area.

Advanced Bioinspired Multifunctional Platforms Focusing on Gut Microbiota Regulation

Gut microbiota plays a crucial role in maintaining host homeostasis, impacting the progression and therapeutic outcomes of diseases, including inflammatory bowel disease, cancer, hepatic conditions, obesity, cardiovascular pathologies, and neurologic disorders, via immune, neural, and metabolic mechanisms. Hence, the gut microbiota is a promising target for disease therapy. The safety and precision of traditional microbiota regulation methods remain a challenge, which limits their widespread clinical application. This limitation has catalyzed a shift toward the development of multifunctional delivery systems that are predicated on microbiota modulation. Guided by bioinspired strategies, an extensive variety of naturally occurring materials and mechanisms have been emulated and harnessed for the construction of platforms aimed at the monitoring and modulation of gut microbiota. This review outlines the strategies and advantages of utilizing bioinspired principles in the design of gut microbiota intervention systems based on traditional regulation methods. Representative studies on the development of bioinspired therapeutic platforms are summarized, which are based on gut microbiota modulation to confer multiple pharmacological benefits for the synergistic management of diseases. The prospective avenues and inherent challenges associated with the adoption of bioinspired strategies in the refinement of gut microbiota modulation platforms are proposed to augment the efficacy of disease treatment.