Introduction to the human gut microbiota

Role of gut microbiome in suppression of cancers

The pathogenesis of cancer is closely related to the disruption of homeostasis in the human body. The gut microbiome plays crucial roles in maintaining the homeostasis of its host throughout lifespan. In recent years, a large number of studies have shown that dysbiosis of the gut microbiome is involved in the entire process of cancer initiation, development, and prognosis by influencing the host immune system and metabolism. Some specific intestinal bacteria promote the occurrence and development of cancers under certain conditions. Conversely, some other specific intestinal bacteria suppress the oncogenesis and progression of cancers, including inhibiting the occurrence of cancers, delaying the progression of cancers and boosting the therapeutic effect on cancers. The promoting effects of the gut microbiome on cancers have been comprehensively discussed in the previous review. This article will review the latest advances in the roles and mechanisms of gut microbiome in cancer suppression, providing a new perspective for developing strategies of cancer prevention and treatment.

Exploring the role of gut microbiota in antibiotic resistance and prevention

BACKGROUND/INTRODUCTION

Antimicrobial resistance (AMR) and the evolution of multiple drug-resistant (MDR) bacteria is of grave public health concern. To combat the pandemic of AMR, it is necessary to focus on novel alternatives for drug development. Within the host, the interaction of the pathogen with the microbiome plays a pivotal role in determining the outcome of pathogenesis. Therefore, microbiome-pathogen interaction is one of the potential targets to be explored for novel antimicrobials.

MAIN BODY

This review focuses on how the gut microbiome has evolved as a significant component of the resistome as a source of antibiotic resistance genes (ARGs). Antibiotics alter the composition of the native microbiota of the host by favouring resistant bacteria that can manifest as opportunistic infections. Furthermore, gut dysbiosis has also been linked to low-dosage antibiotic ingestion or subtherapeutic antibiotic treatment (STAT) from food and the environment.

DISCUSSION

Colonization by MDR bacteria is potentially acquired and maintained in the gut microbiota. Therefore, it is pivotal to understand microbial diversity and its role in adapting pathogens to AMR. Implementing several strategies to prevent or treat dysbiosis is necessary, including faecal microbiota transplantation, probiotics and prebiotics, phage therapy, drug delivery models, and antimicrobial stewardship regulation.

Mucus-penetrating microbiota drive chronic low-grade intestinal inflammation and metabolic dysregulation

Metabolic syndrome is, in humans, associated with alterations in the composition and localization of the intestinal microbiota, including encroachment of bacteria within the colon's inner mucus layer. Possible promoters of these events include dietary emulsifiers, such as carboxymethylcellulose (CMC) and polysorbate-80 (P80), which, in mice, result in altered microbiota composition, encroachment, low-grade inflammation and metabolic syndrome. While assessments of gut microbiota composition have largely focused on fecal/luminal samples, we hypothesize an outsized role for changes in mucus microbiota in driving low-grade inflammation and its consequences. In support of this notion, we herein report that both CMC and P80 led to stark changes in the mucus microbiome, markedly distinct from those observed in feces. Moreover, transfer of mucus microbiota from CMC- and P80-fed mice to germfree mice resulted in microbiota encroachment, low-grade inflammation, and various features of metabolic syndrome. Thus, we conclude that mucus-associated bacteria are pivotal determinants of intestinal inflammatory tone and host metabolism.

The gut-skin axis: a bi-directional, microbiota-driven relationship with therapeutic potential

This review explores the emerging term "gut-skin axis" (GSA), describing the bidirectional signaling that occurs between the skin and the gastrointestinal tract under both homeostatic and disease conditions. Central to GSA communication are the gut and skin microbiota, the microbial communities that colonize these barrier surfaces. By influencing diverse host pathways, including innate immune, vitamin D receptor, and Aryl hydrocarbon receptor signaling, a balanced microbiota contributes to both tissue homeostasis and host defense. In contrast, microbiota imbalance, or dysbiosis at one site, can lead to local barrier dysfunction, resulting in the activation of signaling pathways that can disrupt tissue homeostasis at the other site, potentially leading to inflammatory skin conditions such as atopic dermatitis and psoriasis, or gut diseases like Inflammatory Bowel Disease. To date, most research on the GSA has examined the impact of the gut microbiota and diet on skin health, but recent studies show that exposing the skin to ultraviolet B-light can beneficially modulate both the gut microbiome and intestinal health. Thus, despite the traditional focus of clinicians and researchers on these organ systems as distinct, the GSA offers new opportunities to better understand the pathogenesis of cutaneous and gastrointestinal diseases and promote health at both sites.

Improving the detectability of low-abundance p-cresol in biological matrices by chemical derivatization and LC-MS/MS determination

Gut microbiota produces a wide range of microbial metabolites with potential neuroactive properties. Among these, p-cresol, a by-product of tyrosine breakdown, has gained significant attention in various neuropsychiatric disorders, including autism spectrum disorder. However, current methods fail to detect p-cresol at trace levels in both the systemic circulation and brain, limiting the study of its role in neuropsychiatric disorders. There, the precise and accurate determination of p-cresol at low picogram levels is an unmet analytical need. To address this gap, we developed a highly-sensitive, validated method for quantifying p-cresol at low picogram levels in urine, plasma, and brain using chemical derivatization and liquid chromatography-tandem mass spectrometry (LC-MS/MS). We found that derivatization with 1,2-dimethylimidazole-5-sulfonyl chloride (5-DMIS-Cl or 5-DMISC) increased up to 40-fold the sensitivity compared to traditional dansyl derivatization. Therefore, a method based on 5-DMISC derivatization and sum of transitions was selected for validation. The method was accurate (recoveries 91-100 %) and precise (RSD <15 %) in all tested matrices, enabling detection down to100 pg/mL for urine, 20 pg/mL for plasma, and 0.04 pg/mg for brain tissue. The method was applied to plasma and brain samples from control and p-cresol-treated mice, revealing significant increases in p-cresol levels in treated animals. For the first time, we successfully quantified p-cresol levels in the brain, demonstrating its ability to cross the blood-brain barrier. In summary, this validated method offers a powerful tool for exploring the role of p-cresol -and potentially other phenolic compounds-in the microbiota-gut-brain axis and neuropsychiatric disorders.

Intestinal microbiota and respiratory system diseases: Relationships with three common respiratory virus infections

In recent years, the role of the intestinal microbiota in regulating host health and immune balance has attracted widespread attention. This study provides an in-depth analysis of the close relationship between the intestinal microbiota and respiratory system diseases, with a focus on three common respiratory virus infections, including respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and influenza virus. The research indicates that during RSV infection, there is a significant decrease in intestinal microbial diversity, suggesting the impact of the virus on the intestinal ecosystem. In SARS-CoV-2 infection, there are evident alterations in the intestinal microbiota, which are positively correlated with the severity of the disease. Similarly, influenza virus infection is associated with dysbiosis of the intestinal microbiota, and studies have shown that the application of specific probiotics exhibits beneficial effects against influenza virus infection. Further research indicates that the intestinal microbiota exerts a wide and profound impact on the occurrence and development of respiratory system diseases through various mechanisms, including modulation of the immune system and production of short-chain fatty acids (SCFAs). This article comprehensively analyzes these research advances, providing new perspectives and potential strategies for the prevention and treatment of future respiratory system diseases. This study not only deepens our understanding of the relationship between the intestinal microbiota and respiratory system diseases but also offers valuable insights for further exploring the role of host-microbiota interactions in the development of diseases.

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.

Whole genome sequencing and In silico analysis of the safety and probiotic features of Lacticaseibacillus paracasei FMT2 isolated from fecal microbiota transplantation (FMT) capsules

Lacticaseibacillus paracasei is widely used as a probiotic supplement and food additive in the medicinal and food industries. However, its application requires careful evaluation of safety traits associated with probiotic pathogenesis, including the transfer of antibiotic-resistance genes, the presence of virulence and pathogenicity factors, and the potential disruptions of the gut microbiome and immune system. In this study, we conducted whole genome sequencing (WGS) of L. paracasei FMT2 isolated from fecal microbiota transplantation (FMT) capsules and performed genome annotation to assess its probiotic and safety attributes. Our comparative genomic analysis assessed this novel strain's genetic attributes and functional diversity and unraveled its evolutionary relationships with other L. paracasei strains. The assembly yielded three contigs: one corresponding to the chromosome and two corresponding to plasmids. Genome annotation revealed the presence of 2838 DNA-coding sequences (CDS), 78 ribosomal RNAs (rRNAs), 60 transfer RNAs (tRNAs), three non-coding RNAs (ncRNAs), and 126 pseudogenes. The strain lacked antibiotic resistance genes and pathogenicity factors. Two intact prophages, one Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) region, and three antimicrobial peptide gene clusters were identified, highlighting the genomic stability and antimicrobial potential of the strain. Furthermore, genes linked to probiotic functions, such as mucosal colonization, stress resistance, and biofilm formation, were characterized. The pan-genome analysis identified 3358 orthologous clusters, including 1775 single-copy clusters, across all L. paracasei strains. Notably, L. paracasei FMT2 contained many unique singleton genes, potentially contributing to its distinctive probiotic properties. Our findings confirm the potential of L. paracasei FMT2 for food and therapeutic applications based on its probiotic profile and safety.

The role of gut microbiota and bacterial translocation in the pathogenesis and management of type 2 diabetes mellitus: Mechanisms, impacts, and dietary therapeutic strategies

PURPOSE OF REVIEW

The influence of gut microbiota on Type 2 Diabetes Mellitus (T2DM) is an emerging area of research. This review investigates the relationship between gut microbiota dysbiosis, bacterial translocation, and T2DM. It aims to elucidate how microbial imbalances contribute to the progression of T2DM through bacterial translocation and to evaluate dietary and therapeutic strategies to manage these effects.

RECENT FINDINGS

Recent studies highlight that dysbiosis in T2DM patients often leads to increased systemic inflammation, impaired glucose metabolism, and disrupted gut barrier integrity. These disruptions promote elevated levels of harmful bacterial components, such as lipopolysaccharides, in the bloodstream. This, in turn, is linked to worsening insulin resistance and metabolic dysfunction. Advances in molecular methods and biomarkers have provided deeper insights into bacterial translocation and its impact on diabetes. Dietary interventions, including nutraceutical agents, high-fiber and low-glycemic index diets, as well as the use of probiotics and prebiotics, have shown promise in restoring gut health and mitigating bacterial translocation.

CONCLUSION

Maintaining a balanced gut microbiota and intestinal barrier integrity is crucial for managing T2DM. Therapeutic strategies, including dietary modifications and nutraceuticals, have demonstrated potential in reducing bacterial translocation and systemic inflammation. Continued research is needed to refine these approaches and explore novel treatment modalities for improving metabolic health in T2DM patients.

Synthetic and Biogenic Materials for Oral Delivery of Biologics: From Bench to Bedside

The development of nucleic acid and protein drugs for oral delivery has lagged behind their production for conventional nonoral routes. Over the past decade, the evolution of DNA- and RNA-based technologies combined with the innovation of state-of-the-art delivery vehicles for nucleic acids has brought rapid advancements to the biopharmaceutical field. Nucleic acid therapies have the potential to achieve long-lasting effects, or even cures, by inhibiting or editing genes, which is not possible with conventional small-molecule drugs. However, challenges and limitations must be addressed before these therapies can provide cures for chronic conditions and rare diseases, rather than only offering temporary relief. Nucleic acids and proteins face premature degradation in the acidic, enzyme-rich stomach environment and are rapidly cleared by the liver. To overcome these challenges, various delivery vehicles have been developed to transport therapeutic compounds to the intestines, where the active compounds are released and gut microbiota and mucosal immune system also play an important role. This review provides a comprehensive overview of the promises and pitfalls associated with the oral route of administration of biologics, current delivery systems, applications of orally delivered therapeutics, and the challenges and considerations for translation of nucleic acid and protein therapeutics into clinical practice.

Intervention effects of greenspace exposure on human microbiota: A randomized controlled trial in Chinese young adults

Enriching human microbiota has been proposed as a mechanism by which greenspace exposure improves human health. The existing evidence is scarce with few studies able to evaluate causality. We conducted a randomized controlled trial of 30 healthy undergraduate students to explore the intervention effects of greenspace on human gut and oral microbiota alpha-diversity, composition, differential genera and functional pathways. The study participants were divided into three groups, including outdoor greenspace (GS) group, outdoor non-greenspace (NGS) group, and indoor group, who visited a park, an open space without vegetation, and a classroom, respectively, for two hours per day over seven days. Differences in microbial alpha-diversity and composition across various groups were tested using Wilcoxon test and permutational multivariate analysis of variance, respectively. Linear discriminant analysis effect size analysis was performed to test differences in genera and functional pathways. Greenspace intervention significantly increased gut microbiota alpha-diversity, especially the observed Amplicon Sequence variant indexes and the Faith indexes (both p < 0.05). In addition, the intervention substantially changed the composition of gut microbiota, of which the relative abundances of potentially beneficial bacteria increased. Further, the greenspace intervention affected several functional pathways of gut microbiota, including "substance dependence", "specific types of cancer", and "viral infectious diseases". However, we did not find any significant effect of greenspace intervention on oral microbiota. Our results suggest that greenspace intervention diversifies the gut microbiota and alters its composition. These findings could help to reinforce the potential of increasing people's access to greenspace as a public health intervention.

Enriched pathways in gut microbiome predict response to immune checkpoint inhibitor treatment across demographic regions and various cancer types

Understanding the effect of gut microbiota function on immune checkpoint inhibitor (ICI) responses is urgently needed. Here, we integrated 821 fecal metagenomes from 12 datasets to identify differentially abundant genes and construct random forest models to predict ICI response. Gene markers demonstrated excellent predictive performance, with an average area under the curve (AUC) of 0.810. Pathway analyses revealed that quorum sensing (QS), ABC transporters, flagellar assembly, and amino acid biosynthesis pathways were enriched between responders (R) and non-responders (NRs) across 12 datasets. Furthermore, luxS, manA, fliC, and trpB exhibited consistent changes between R and NR across 12 datasets. Follow-up microbiota transplant experiments showed that inter-species signaling by different QS autoinducer-2 (AI-2) molecules (synthesized by luxS) can act on overall community function to promote the colonization of Akkermansia muciniphila, which is associated with superior ICI responses. Together, our data highlight the role of gut microbiota function in modulating the microbiome and antitumor immunity.

Progress in Probiotic Science: Prospects of Functional Probiotic-Based Foods and Beverages

This comprehensive review explores the evolving role of probiotic-based foods and beverages, highlighting their potential as functional and "future foods" that could significantly enhance nutrition, health, and overall well-being. These products are gaining prominence for their benefits in gut health, immune support, and holistic wellness. However, their future success depends on addressing critical safety concerns and navigating administrative complexities. Ensuring that these products "do more good than harm" involves rigorous evaluations of probiotic strains, particularly those sourced from the human gastrointestinal tract. Lactic acid bacteria (LABs) serve as versatile and effective functional starter cultures for the development of probiotic foods and beverages. The review emphasizes the role of LABs as functional starter cultures and the development of precision probiotics in advancing these products. Establishing standardized guidelines and transparent practices is essential, requiring collaboration among regulatory bodies, industry stakeholders, and the scientific community. The review underscores the importance of innovation in developing "friendly bacteria," "super probiotics," precision fermentation, and effective safety assessments. The prospects of functional probiotic-based foods and beverages rely on refining these elements and adapting to emerging scientific advancements. Ultimately, empowering consumers with accurate information, fostering innovation, and maintaining stringent safety standards will shape the future of these products as trusted and beneficial components of a health-conscious society. Probiotic-based foods and beverages, often infused with LABs, a "friendly bacteria," are emerging as "super probiotics" and "future foods" designed to "do more good than harm" for overall health.

Characterization of bioaerosol exposures in wastewater treatment plant workers and serum levels of lung and inflammatory markers

Wastewater treatment plant (WWTP) workers are exposed to bioaerosols containing bacteria, fungi, and endotoxin, potentially posing health risks to workers. This study quantified personal exposure levels to airborne bacteria and fungi, endotoxin, and dust among 44 workers during two seasons at four WWTPs. Associations between the exposure measurements and serum levels of biomarkers CRP, SAA, and CC16 were also assessed. The potential deposition of viable microorganisms in workers' airways were explored using stationary fractionating samplers. Microbial communities were characterized using long-read nanopore amplicon sequencing and MALDI-TOF mass spectrometry to identify species, including pathogenic or allergenic microorganisms. We found that bacterial and fungal exposure levels were significantly associated with work task (p < 0.001 and p = 0.00041, respectively), with high exposure variability within and between tasks. Workshop, sewer system inspection, and sewer cleaning were associated with the highest exposure levels. A significant positive correlation was found between CRP and bacterial exposure (p = 0.013), while significant negative correlations were found between CRP and endotoxin and dust exposures (p = 0.012 and p = 0.018, respectively). No significant associations were found between SAA or CC16 and the exposure measures. Microbial community composition in bioaerosols differed significantly between some work tasks while others showed similar compositions. Viable hazardous microorganisms such as Clostridium perfringens and Aspergillus fumigatus were found in workers' exposures and in respiratory fractions of stationary air samples, indicating potential lung deposition. Further research is needed to assess possible long-term health risks from bioaerosol exposure at WWTPs.

Uncovering the Effects of Different Formulae of Milk Powders on the Fecal Microorganisms and Metabolites of Bengal Tiger (Panthera tigris spp. tigris) Cubs

In order to optimize diets for Bengal tiger cubs and improve their health condition and survival rates, we conducted microbiota and metabolomics analyses on fecal samples from Bengal tiger cubs fed goat and dog milk replacer formulae. The results showed that there were significant differences in fecal microorganisms and metabolites between the two groups. At the phylum level, the major components of the microbial composition in the feces of cubs were Firmicutes, Actinobacteriota, Proteobacteria, Bacteroidota and Fusobacteriota. In addition, the abundance of gut microbiota varied significantly between the two groups of tiger cubs. The fecal microbiota of the tiger cubs fed dog milk replacer powder exhibited an increase in probiotic bacteria (Anaerostipes and Clostridium_scindens) (p < 0.05), and the microbial community tended to be more balanced. Metabolomics data further elucidated that feeding different milk formulae significantly affected the fecal metabolites and metabolic pathways in the Bengal tiger cubs. In the dog milk replacer powder group, 76 metabolites were up-regulated (p < 0.05), and 278 metabolites were down-regulated (p < 0.05), particularly affecting the metabolism of vitamin D3, vitamin B5, isoleucine, valine, phenylalanine and oleic acid. At the same time, 19 metabolic pathways were affected (p < 0.05), including the amino acid metabolism, lipid metabolism and nucleotide metabolism pathways. In conclusion, this study confirms that milk formula composition affects the gut microbiota and metabolism of Bengal tiger cubs. These findings may provide new insights into how different milk powder formulae and dietary strategies influence the regulation of gut microbiota and overall health in Bengal tiger cubs.

Activity of GPCR-targeted drugs influenced by human gut microbiota metabolism

Microbiota-mediated drug metabolism can affect pharmacological efficacy. Here we conducted a systematic comparative metabolomics investigation of drug metabolism modes by evaluating the impacts of human gut commensal bacteria on 127 G-protein-coupled receptor (GPCR)-targeted drugs. For the most extensively metabolized drugs in our screen, we elucidated both conventional and unconventional drug transformations and the corresponding activities of generated metabolites. Comparisons of drug metabolism by a gut microbial community versus individual species revealed both taxon intrinsic and collaborative processes that influenced the activity of the metabolized drugs against target GPCRs. We also observed iloperidone inactivation by generating unconventional metabolites. The human gut commensal bacteria mixture incorporated sulfur in the form of a thiophene motif, whereas Morganella morganii used a cascade reaction to incorporate amino-acid-derived tricyclic systems into the drug metabolites. Our results reveal a broad impact of human gut commensal bacteria on GPCR-targeted drug structures and activities through diverse microbiota-mediated biotransformations.

Molecular hydrogen as a potential mediator of the antitumor effect of inulin consumption

Inulin consumption and dihydrogen (H2) administration both exert antitumor effects on preclinical models as well as in clinical trials. As H2 is one of the major byproducts of inulin fermentation by bacterial species of the gut microbiota (GM), we hypothesized that H2 could mediate the antitumor effects of inulin. To provide evidence in favor of this hypothesis, we first determined the pattern of H2-exposure to which mice are subjected after inulin administration and developed an inhaled hydrogen therapy (H2T) protocol replicating this pattern. We then compared the effects on circulating immunity of a two-week daily inulin gavage with those of the corresponding H2T. We also compared the effects of inulin supplementation to those of the corresponding H2T on implanted melanoma growth and infiltration by T lymphocytes. Inulin and H2T induced a similar increase in circulating CD4+ and CD8+ T cells. In addition, both treatments similarly inhibited melanoma tumor growth. These results support a mechanism by which the H2 resulting from inulin fermentation by the GM diffuses across the intestinal barrier and stimulates the immunosurveillance responsible for the antitumor effect.

Encapsulation of L. fermentum with chitosan-alginate enhances its bioactivity against acrylamide toxicity in D.mel

Acrylamide (ACR), a neurotoxin typically present in thermally processed foods, is a substantial risk to people. The objective of this research is to develop synbiotic capsules with natural substances such as chitosan, alginate, and L. fermentum. Encapsulation is a significant tool in medicine, helping to improve targeted medication delivery and bioavailability. The chitosan/alginate-encapsulated probiotic (CAP) beads increase the bioavailability of probiotics in the gut, allowing for a more effective response to ACR-induced toxicity. The combination of prebiotic and probiotic activity improves stability, viability, and gastrointestinal delivery. We developed CAP beads and assessed their survivability under simulated gastrointestinal conditions, encapsulating efficiency, and release profile. The efficacy of these beads in reducing the harmful effects of ACR was subsequently investigated using a Drosophila melanogaster model. Under co-exposure and pre-treatment settings, in vivo studies revealed restoration of locomotor activities, redox balance, and ovarian mitochondrial membrane potential in flies treated with CAP beads. Furthermore, implying the indirect impact of CAP beads on gut microbiota and xenobiotic metabolism, pre-treatment with CAP more successfully restored the expression of important antioxidant and stress-related genes, including sod, cat, InR, rpr, and p53.

Interplay between gut microbiota and exosome dynamics in sleep apnea

Sleep-disordered breathing (SDB) is characterized by recurrent reductions or interruptions in airflow during sleep, termed hypopneas and apneas, respectively. SDB impairs sleep quality and is linked to substantive health issues including cardiovascular and metabolic disorders, as well as cognitive decline. Recent evidence suggests a link between gut microbiota (GM) composition and sleep apnea. Indeed, GM, a community of microorganisms residing in the gut, has emerged as a potential player in various diseases, and several studies have identified associations between sleep apnea and GM diversity along with shifts in bacterial populations. Additionally, the concept of "leaky gut," a compromised intestinal barrier with potentially increased inflammation, has emerged as another key player in the potential bidirectional relationship between GM and sleep apnea. One of the potential effectors could be extracellular vesicles (EVs) underlying gut-brain communication pathways that are relevant to sleep regulation and function. Thus, therapeutic implications afforded by targeting the GM or exosomes for sleep apnea management have surfaced as promising areas of research. This review explores current understanding of the relationship between GM, exosomes and sleep apnea, highlighting key research dynamics and potential mechanisms. A comprehensive review of the literature was conducted, focusing on studies investigating GM composition, intestinal barrier function and gut-brain communication in relation to sleep apnea.

Simulated Media for Mimicking the Human Environment In Vitro

The phrase 'All models are wrong but some are useful' spoken by George Box in 1976 is as relevant today as ever. Modern research relies heavily on models and the use of in vitro models is the cornerstone of developing novel treatments for various infectious diseases. Simple growth media have been, and still are, heavily used when performing research involving biofilms and infectious pathogens. However, using modern technologies, large discrepancies are now being revealed between bacteria grown in simple media versus those grown in more authentic media. These discrepancies can lead to significant differences in bacterial tolerances, growth patterns, biofilm formation abilities, etc. Hence, if the aim is to replicate the in vivo situation in a laboratory setting, the creation of realistic simulated bodily fluids should be prioritised. This paper presents a range of simulated human fluids from various body sites where infections often occur. Bacterial behaviour has been evaluated in all these media and is often compared to a simple growth medium counterpart. In all instances, significant differences are observed which might lead to important discrepancies, particularly in potential treatment efficiency. We hope this may serve as inspiration for any researcher doing in vitro work, attempting to mimic reality.

p-Hydroxycinnamic Acids: Advancements in Synthetic Biology, Emerging Regulatory Targets in Gut Microbiota Interactions, and Implications for Animal Health

p-hydroxycinnamic acids (p-HCAs), a class of natural phenolic acid compounds extracted from plant resources and widely distributed, feature a C6-C3 phenylpropanoid structure. Their antioxidant, anti-inflammatory, and antibacterial activities have shown great potential for applications in food and animal feed. The interactions between p-HCAs and the gut microbiota, as well as their subsequent effects on animal health, have increasingly attracted the attention of researchers. In the context of a greener and safer future, the progress and innovation in biosynthetic technology have occupied a central position in ensuring the safety of food and feed. This review emphasizes the complex mechanisms underlying the interactions between p-HCAs and the gut microbiota, providing a solid explanation for the remarkable bioactivities of p-HCAs and their subsequent impact on animal health. Furthermore, it explores the advancements in the synthetic biology of p-HCAs. This review could aid in a basis for better understanding the underlying interactions between p-HCAs and gut microbiota and animal health.

Deciphering T-cell exhaustion in the tumor microenvironment: paving the way for innovative solid tumor therapies

In solid tumors, the tumor microenvironment (TME) is a complex mix of tumor, immune, stromal cells, fibroblasts, and the extracellular matrix. Cytotoxic T lymphocytes (CTLs) constitute a fraction of immune cells that may infiltrate into the TME. The primary function of these T-cells is to detect and eliminate tumor cells. However, due to the immunosuppressive factors present in the TME primarily mediated by Myeloid-Derived Suppressor Cells (MDSCs), Tumor associated macrophages (TAMs), Cancer Associated Fibroblasts (CAFs) as well as the tumor cells themselves, T-cells fail to differentiate into effector cells or become dysfunctional and are unable to eliminate the tumor. In addition, chronic antigen stimulation within the TME also leads to a phenomenon, first identified in chronic lymphocytic choriomeningitis virus (LCMV) infection in mice, where the T-cells become exhausted and lose their effector functions. Exhausted T-cells (Tex) are characterized by the presence of remarkably conserved inhibitory receptors, transcription and signaling factors and the downregulation of key effector molecules. Tex cells have been identified in various malignancies, including melanoma, colorectal and hepatocellular cancers. Recent studies have indicated novel strategies to reverse T-cell exhaustion. These include checkpoint inhibitor blockade targeting programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin-domain containing-3 (Tim-3), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), or combinations of different immune checkpoint therapies (ICTs) or combination of ICTs with cytokine co-stimulation. In this review, we discuss aspects of T-cell dysfunction within the TME with a focus on T-cell exhaustion. We believe that gaining insight into the mechanisms of T-cell exhaustion within the TME of human solid tumors will pave the way for developing therapeutic strategies to target and potentially re-invigorate exhausted T-cells in cancer.

Serotonin signaling to regulate energy metabolism: a gut microbiota perspective

Serotonin is one of the most potent gastrointestinal, peripheral, and neuronal signaling molecules and plays a key role in regulating energy metabolism. Accumulating evidence has shown the complex interplay between gut microbiota and host energy metabolism. In this review, we summarize recent findings on the role of gut microbiota in serotonin metabolism and discuss the complicated mechanisms by which serotonin, working in conjunction with the gut microbiota, affects total body energy metabolism in the host. Gut microbiota affects serotonin synthesis, storage, release, transport, and catabolism. In addition, serotonin plays an indispensable role in regulating host energy homeostasis through organ crosstalk and microbe-host communication, particularly with a wide array of serotonergic effects mediated by diverse serotonin receptors with unique tissue specificity. This fresh perspective will help broaden the understanding of serotonergic signaling in modulating energy metabolism, thus shedding light on the design of innovative serotonin-targeting strategies to treat metabolic diseases.

Gut microbiota and microRNAs as biomarkers in Parkinson's disease: early identification, diagnostic and potential treatments

The gut microbiota can affect both the enteric and the central nervous system, influencing individuals and their brain regulation. In this work, different pieces of scientific evidence are discussed, showing the relationship between changes in the microbiota and neurocognitive deterioration, focussing on Parkinson's disease (PD). Other factors that may cause or contribute to PD aetiology are the interactions between environmental factors and genetic susceptibility. According to the existing literature, there are several methods for the identification of neurocognitive impairment in different neurological diseases. However, such methods do not allow early identification, and therefore, the possibility of using other types of more effective diagnostic biomarkers in PD has also been investigated. Since this disease is characterised by specific microRNA (miRNA) expression, and the gut microbiota is an important factor in both PD and miRNA expression, the aim of this review is thoroughly analysing the role of microbiota and microRNAs in PD development. In addition, the relationship between these two factors and potential treatments will be also discussed.

Oxidative Stress, Gut Microbiota, and Extracellular Vesicles: Interconnected Pathways and Therapeutic Potentials

Oxidative stress (OS) and gut microbiota are crucial factors influencing human health, each playing a significant role in the development and progression of chronic diseases. This review provides a comprehensive analysis of the complex interplay between these two factors, focusing on how an imbalance between reactive oxygen species (ROS) and antioxidants leads to OS, disrupting cellular homeostasis and contributing to a range of conditions, including metabolic disorders, cardiovascular diseases, neurological diseases, and cancer. The gut microbiota, a diverse community of microorganisms residing in the gastrointestinal tract, is essential for regulating immune responses, metabolic pathways, and overall health. Dysbiosis, an imbalance in the gut microbiota composition, is closely associated with chronic inflammation, metabolic dysfunction, and various diseases. This review highlights how the gut microbiota influences and is influenced by OS, complicating the pathophysiology of many conditions. Furthermore, emerging evidence has identified extracellular vesicles (EVs) as critical facilitators of cellular crosstalk between the OS and gut microbiota. EVs also play a crucial role in signaling between the gut microbiota and host tissues, modulating immune responses, inflammation, and metabolic processes. The signaling function of EVs holds promise for the development of targeted therapies aimed at restoring microbial balance and mitigating OS. Personalized therapeutic approaches, including probiotics, antioxidants, and fecal microbiota transplantation-based strategies, can be used to address OS-related diseases and improve health outcomes. Nonetheless, further research is needed to study the molecular mechanisms underlying these interactions and the potential of innovative interventions to offer novel strategies for managing OS-related diseases and enhancing overall human health.

Gut microbiome differences and disease risk in colorectal cancer relatives and healthy individuals

Given the heightened focus on high-risk populations, this study aimed to provide insights into early susceptibility and preventive strategies for colorectal cancer (CRC) by focusing on high-risk populations. In this research, fecal samples from 1,647 individuals across three discovery cohorts and nine external validation cohorts were sequenced using whole-genome metagenomic sequencing. A prediction model based on random forest was constructed using the nine external cohorts and independently validated with the three discovery cohorts. A disease probability (POD) model based on microbial biomarkers was developed to assess CRC risk. We found that the gut microbiome composition of CRC relatives differed from that of controls, with enrichment of species such as Fusobacterium and Bacteroides and a reduction in beneficial genera like Coprococcus and Roseburia. Additionally, dietary red meat intake emerged as a risk factor. The POD model indicated an elevated risk of CRC in unaffected relatives. The findings suggest that the POD for CRC may be increased in unaffected relatives or individuals living in shared environments, although this difference did not reach statistical significance. Our study introduces a novel framework for assessing the risk of colorectal cancer in ostensibly healthy individuals.

Factors affecting dysbiosis of the gut microbiota in the elderly and the progress of interventions in traditional Chinese and Western medicine

As the population ages, intestinal health in the elderly has become a key area of concern, with gut microbiota dysbiosis emerging as a significant issue. This review summarizes the factors influencing dysbiosis and interventions from both traditional Chinese medicine (TCM) and Western medicine, offering a reference for future research. A comprehensive search of global databases up to March 2024 identified 617 original studies on gut microbiota dysbiosis in individuals aged 65 and older. After applying strict PRISMA guidelines, 20 articles met the inclusion criteria. Key findings are summarized in four areas: 1) the definition and mechanisms of dysbiosis, 2) evaluation tools for gut microbiota imbalance, 3) factors contributing to dysbiosis in the elderly, and 4) pharmacological treatments. Both TCM and Western medicine offer unique advantages in managing gut microbiota dysbiosis, and the choice of intervention should be tailored to the individual's condition. Future research should focus on optimizing integrated TCM and Western medicine approaches to improve outcomes for elderly patients with gut microbiota dysbiosis.

Widespread heteroresistance to antibiotics in Lactobacillus species

Lactobacilli are prevalent members of the intestinal and reproductive tract microbiota of humans and other species. They are commonly used in probiotics and various food products due to their beneficial effects on human health. For example, these beneficial microbes are used to treat diarrhea caused by antibiotic therapy and are commonly given during antibiotic treatment. Despite the many studies conducted to understand the beneficial effects of Lactobacilli, less is known about their resistance and heteroresistance to antibiotics. In this study, we evaluated the resistance heterogeneity in eight Lactobacillus species. Our results demonstrate that several Lactobacilli species, including Lactobacillus rhamnosus, are heteroresistant to antibiotics, a recently discovered phenotype commonly seen in multidrug-resistant organisms that cause clinical failures but understudied in commensals and probiotics.

Betaine regulates the gut-liver axis: a therapeutic approach for chronic liver diseases

Chronic liver disease is defined by persistent harm to the liver that might result in decreased liver function. The two prevalent chronic liver diseases are alcohol-associated liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD). There is ample evidence that the pathogenesis of these two chronic liver diseases is closely linked to gastrointestinal dysfunctions that alters the gut-liver crosstalk. These alterations are mediated through the imbalances in the gut microbiota composition/function that combined with disruption in the gut barrier integrity allows for harmful gut microbes and their toxins to enter the portal circulation and reach the liver to elicit an inflammatory response. This leads to further recruitment of systemic inflammatory cells, such as neutrophils, T-cells, and monocytes into the liver, which perpetuate additional inflammation and the development of progressive liver damage. Many therapeutic modalities, currently used to prevent, attenuate, or treat chronic liver diseases are aimed at modulating gut dysbiosis and improving intestinal barrier function. Betaine is a choline-derived metabolite and a methyl group donor with antioxidant, anti-inflammatory and osmoprotectant properties. Studies have shown that low betaine levels are associated with higher levels of organ damage. There have been several publications demonstrating the role of betaine supplementation in preventing the development of ALD and MASLD. This review explores the protective effects of betaine through its role as a methyl donor and its capacity to regulate the protective gut microbiota and maintain intestinal barrier integrity to prevent the development of these chronic liver diseases. Further studies are needed to enhance our understanding of its therapeutic potential that could pave the way for targeted interventions in the management of not only chronic liver diseases, but other inflammatory bowel diseases or systemic inflammatory conditions.

Medication-resistant epilepsy is associated with a unique gut microbiota signature

OBJECTIVE

Dysfunction of the microbiota-gut-brain axis is emerging as a new pathogenic mechanism in epilepsy, potentially impacting on medication response and disease outcome. We investigated the composition of the gut microbiota in a cohort of medication-resistant (MR) and medication-sensitive (MS) pediatric patients with epilepsy.

METHODS

Children with epilepsy of genetic and presumed genetic etiologies were evaluated clinically and subgrouped into MR and MS. Age-matched healthy controls (HCs) were also recruited. A food diary was used to evaluate nutritional habits, and the Rome IV questionnaire was used to record gastrointestinal symptoms. The microbiota composition was assessed in stool samples through 16S rRNA. α-Diversity (AD) and β-diversity (BD) were calculated, and differential abundance analysis was performed using linear multivariable models (significance: p.adj < .05).

RESULTS

Forty-one patients (MR:MS = 20:21) with a mean age of 7.2 years (±4.6 SD) and 27 age-matched HCs were recruited. No significant differences in AD were found when comparing patients and HCs. Significant positive correlation was found between AD and age (Chao1 p.adj = .0004, Shannon p.adj = .0004, Simpson p.adj = .0028). BD depicted a different bacterial profile in the epilepsy groups compared to HCs (MS vs. HC: Bray-Curtis F = 1.783, p = .001; Jaccard F = 1.24, p = .001; MR vs. HC: Bray-Curtis F = 2.24, p = .001; Jaccard F = 1.364, p = .001). At the genus level, the epilepsy groups were characterized by a significant increase in Hungatella (MS vs. HC: +4.95 log2 change; MR vs. HC: +6.72 log2 change); the [Eubacterium] siraeum group changed between the MR and MS subgroups.

SIGNIFICANCE

Epileptic patients display unique gut metagenomic signatures compared to HCs. Moreover, a different ratio of the butyrate-producing [Eubacterium] siraeum group suggests dissimilarities between patients based on the response to antiseizure medications.

Gut microbial signatures associated with uremic pruritus in hemodialysis patients

BACKGROUND

The gut microbiota influences the gut-skin-kidney axis, but its role in uremic pruritus remains poorly understood. This study aimed to explore differences in gut microbial profiles between hemodialysis (HD) patients with and without uremic pruritus and identify potential microbial signatures associated with uremic pruritus.

METHODS

We conducted a cross-sectional study of HD patients with and without uremic pruritus. Stool samples were collected from all participants, and the gut microbiota composition was analyzed using 16S rRNA gene sequencing. Alpha and beta diversity metrics were calculated to assess microbial diversity. LEfSe analysis was performed to identify differentially abundant taxa associated with uremic pruritus.

RESULTS

Among 93 HD patients (mean age: 61.9 years, 31.2 % female), uremic pruritus occurred in 61.3 % of patients, with a median visual analog scale (VAS) score of 4.0. While alpha diversity did not differ significantly between groups, beta diversity analysis revealed significant compositional differences (unweighted UniFrac metric, P = 0.004; weighted UniFrac metric, P < 0.001). LEfSe analysis revealed significant enrichment of the order Pasteurellales, family Pasteurellaceae and genus Dialister in patients with uremic pruritus, whereas the order Corynebacteriales was more abundant in patients without pruritus (P < 0.05, LDA score > 3).

CONCLUSION

In this study, we found significant differences in gut microbiota composition between HD patients with and without uremic pruritus and identified potential microbial biomarkers for uremic pruritus. Further studies are needed to elucidate the underlying mechanisms and explore microbiota-targeted therapeutic interventions.

Research Status and Trends of Gut Microbiota and Intestinal Diseases Based on Bibliometrics

Gut microbiota plays an important role in gut health, and its dysbiosis is closely related to the pathogenesis of various intestinal diseases. The field of gut microbiota and intestinal diseases has not yet been systematically quantified through bibliometric methods. This study conducted bibliometric analysis to delineate the evolution of research on gut microbiota and intestinal diseases. Data were sourced from the Web of Science Core Collection database from 2009 to 2023 and were scientometrically analyzed using CiteSpace. We have found that the number of annual publications has been steadily increasing and showing an upward trend. China and the Chinese Academy of Sciences are the country and institution with the most contributions, respectively. Frontiers in Microbiology and Nutrients are the journals with the most publications, while Plos One and Nature are the journals with the most citations. The field has shifted from focusing on traditional descriptive analysis of gut microbiota composition to exploring the causal relationship between gut microbiota and intestinal diseases. The research hotspots and trends mainly include the correlation between specific intestinal diseases and gut microbiota diversity, the mechanism of gut microbiota involvement in intestinal diseases, the exploration of important gut microbiota related to intestinal diseases, and the relationship between gut microbiota and human gut health. This study provides a comprehensive knowledge map of gut microbiota and intestinal diseases, highlights key research areas, and outlines potential future directions.

Antibiotic-induced gut dysbiosis: unraveling the gut-heart axis and its impact on cardiovascular health

Cardiovascular diseases (CVDs) remain the major cause of morbidity and mortality amongst people of all ages across the world. Research suggests that the initiation and progression of CVDs are associated with antibiotic-induced gut dysbiosis. Antibiotics are primarily intended to be used to treat bacterial infections, which can alter gut microbiota (GM) composition, by lowering the abundance of beneficial bacteria, like Firmicutes, Bacteroidetes, and increasing the profusion of Enterobacteriaceae, leading to harm on gut health. Additionally, it reduces short-chain fatty acids (SCFAs) and bile acid metabolism, increases trimethylamine N-oxide (TMAO) production, intestinal permeability allowing lipopolysaccharide (LPS) and TMAO into systemic circulation. SCFAs play a key role in lipid metabolism, inflammation, and strengthening of the intestinal barrier, and participate in CVDs through FFAR2 and FFAR3 receptors, whereas dysbiosis reduces SCFAs levels and worsens these effects. TMAO enhances oxidative stress, inflammation, endothelial dysfunction, and cholesterol dysregulation, thus worsening CVDs. Furthermore, LPS develops systemic inflammation, insulin resistance, and endothelial dysfunction by activating the NF-κB pathway. Dysbiosis also affects bile acid synthesis, disrupting lipid and glucose metabolism, further participating in the progression of CVDs. This article aims to explore the role of gut dysbiosis in various CVDs, including congenital heart disease, hypertension, valvular heart disease, coronary heart disease, and heart failure. Furthermore, this article aims to bridge the knowledge gap regarding the gut-heart axis by exploring how antibiotics alter the gut microbiota homeostasis, further contributing to the development of CVDs and therapeutic interventions that reduce cardiovascular risks and restore the gut microbiota homeostasis.

Expandable konjac fiber modulates appetite and chyme digestion in vivo by stomach-intestine-brain axis

Appetite regulation is a lifestyle intervention strategy to maintain health. The regulatory effects of dietary fiber (especially insoluble dietary fiber), as a crucial element of the nutritional composition, on appetite remain poorly understood. This study investigated modulatory effects of konjac fiber (KF, with high and low expansion) and konjac powder (KP) on chyme digestion, gastrointestinal hormones, intestinal microbiota, appetite genes in hypothalamus, GLP-1 receptor (GLP-1R) protein in various tissues of rats by dietary intervention. The results showed that highly-expanded konjac fiber (HKF) significantly delayed gastric emptying and inhibited hydrolysis of chyme. Konjac fiber (KF), especially HKF, and KP increased short-chain fatty acid (SCFA) content and plasma glucagon-like peptide-1 (GLP-1) levels. HKF upregulated the expression of GLP-1R protein in rat stomachs, nucleus tractus solitaries (NTS), and area postrema (AP) of rat brain, but down-regulated the expression of appetite gene AgRP/NPY in hypothalamus, thus, inhibiting appetite, reducing daily food intake and weight gain. Overall, this study reveals the mechanism through which expandable konjac fiber modulates appetite and chyme digestion in vivo by stomach-intestine-brain axis. Our findings provide an insight into the regulatory effects of insoluble dietary fiber on appetite and offered a valuable reference for the development of satiety-enhancing functional foods.

The role of the urinary microbiome in genitourinary cancers

Genitourinary cancers account for 20% of cancer instances globally and pose a substantial burden. The microbiome, defined as the ecosystem of organisms that reside within and on the human body, seems to be closely related to multiple cancers. Research on the gut microbiome has yielded substantial insights into the interactions of this entity with the immune system and cancer therapeutic efficacy, whereas the urinary microbiome has been relatively less well-studied. Advances in next-generation sequencing technologies led to new discoveries in the urinary microbiome, which might aid in early detection, risk stratification and personalized treatment strategies in genitourinary cancers. Mechanistic investigations have also suggested a role for the urinary microbiome in modulating the tumour microenvironment and host immune response. For example, distinct urinary microbial signatures have been linked to bladder cancer occurrence and recurrence risk, with specific taxa associated with cytokine production and inflammation. Urinary microbiome signatures have also been explored as potential biomarkers for non-invasive cancer detection. However, challenges remain in standardizing methodologies, validating findings across studies, and establishing causative mechanisms. As investigations into the urinary microbiome continue to evolve, so does the potential for developing microbiome-modulating therapies and enhancing diagnostic capabilities to improve outcomes in patients with genitourinary cancers.

Gut Microbial Control of Neurotransmitters and Their Relation to Neurological Disorders: A Comprehensive Review

The study explores the vital role of gut microbiota in regulating neurotransmitters and its subsequent effects on brain function and mental health. It aims to unravel the mechanisms by which microbial metabolites influence neurotransmitter synthesis and signaling. The ultimate goal is to identify potential therapeutic strategies targeting gut microbiota for the management and treatment of neurological disorders, such as depression, autism spectrum disorder (ASD), anxiety, and Parkinson's disease. The review synthesizes current research on the gut-brain axis, focusing on the influence of gut microbial metabolites on key neurotransmitters, including dopamine, serotonin, and gamma-aminobutyric acid (GABA). It incorporates a multidisciplinary approach, linking microbiology, neurobiology, and clinical research. Each section presents an in-depth review of scientific studies, clinical trials, and emerging therapeutic strategies. The findings highlight the intricate interplay between gut microbiota and the central nervous system. Gut microbes significantly impact the synthesis and signaling of crucial neurotransmitters, which play a pivotal role in neurological health. Evidence supports the hypothesis that modulating gut microbiota can alter neurotransmitter output and alleviate symptoms associated with neurological disorders. Notable therapeutic potentials include microbiota-targeted interventions for managing depression, ASD, anxiety, and Parkinson's disease. This comprehensive analysis underscores the critical connection between gut microbiota and neurological health. By bridging gaps between microbiology, neurobiology, and clinical practice, the study opens avenues for innovative therapeutic approaches. It provides a valuable resource for researchers, clinicians, and students, emphasizing the need for continued investigation into gut microbiota's role in neurological disorders and its therapeutic potential.

The microbiome: what a neurologist needs to know

The gastrointestinal tract is inhabited by trillions of micro-organisms that form the gut microbiome, which serves various functions that can influence neurological pathways. It can release metabolites that could affect the nervous system. The bidirectional communication between the intestine and the central nervous system is known as the gut-brain axis. This communication can be impacted by the microbiota in various direct and indirect ways. There has been a suggested connection between the microbiome and many neurological disorders, including epilepsy, Alzheimer's disease, Parkinson's disease and multiple sclerosis. This has been explored in human and animal studies. While no microbial biomarkers have been identified yet, alterations in several taxa have been suggested to be associated with disease states. The potential of the microbiome to modulate neurological function has sparked multiple clinical trials using gut-altering treatments, some with positive preliminary results.

Beyond the gut: Unraveling the multifaceted influence of microbiome on cardiovascular health

Cardiovascular disease is one of the leading causes of death worldwide. Even while receiving adequate pharmacological treatment for their hypertension, people are nonetheless at greater risk for cardiovascular disease. There is growing evidence that the gut microbiota may have major positive and negative effects on blood pressure and illnesses related with it as more study into this topic is conducted. Trimethylamine n-oxide (TMAO) and short-chain fatty acids (SCFA) are two major by-products of the gut microbiota. TMAO is involved in the formation of other coronary artery diseases, including atherosclerosis and hypertension, while SCFAs play an important role in controlling blood pressure. Numerous investigations have confirmed the established link between dietary salt intake and hypertension. Reducing sodium in the diet is linked to lower rates of cardiovascular disease morbidity and mortality as well as lower rates of blood pressure and hypertension. In both human and animal research, high salt diets increase local and systemic tissue inflammation and compromise gut architecture. Given that the gut microbiota constantly interacts with the immune system and is required for the correct maturation of immune cells, it is scientifically conceivable that it mediates the inflammatory response. This review highlights the therapeutic possibilities for focusing on intestinal microbiomes as well as the potential functions of the gut microbiota and its metabolites in the development of hypertension.

Current Trends in Pediatric Migraine: Clinical Insights and Therapeutic Strategies

Background/Objectives: Pediatric migraine is a prevalent neurological disorder that significantly impacts children's quality of life, academic performance, and social interactions. Unlike migraines in adults, pediatric migraines often present differently and involve unique underlying mechanisms, making diagnosis and treatment more complex. Methods: This review discusses the clinical phases of pediatric migraine, key trigger factors, sex- and age-related differences, and the role of childhood maltreatment in migraine development. We also discuss episodic syndromes such as cyclic vomiting syndrome, abdominal migraine, benign paroxysmal vertigo, and benign paroxysmal torticollis, along with comorbidities such as psychiatric disorders, sleep disturbances, and epilepsy. Results: The underlying pathophysiological mechanisms for pediatric migraines, including genetic predispositions, neuroinflammation, and gut microbiota dysbiosis, are summarized. Current therapeutic strategies, including conventional and emerging pharmacological treatments, nutraceuticals, and non-pharmacological approaches, are evaluated. Non-pharmacological strategies, particularly evidence-based lifestyle interventions such as stress management, diet, hydration, sleep, exercise, screen time moderation, and cognitive behavioral therapy, are highlighted as key components of migraine prevention and management. The long-term prognosis and follow-up of pediatric migraine patients are reviewed, emphasizing the importance of early diagnosis, and tailored multidisciplinary care to prevent chronic progression. Conclusions: Future research should focus on novel therapeutic targets and integrating gut-brain axis modulation, with a need for longitudinal studies to better understand the long-term course of pediatric migraine.

Understanding dysbiosis and resilience in the human gut microbiome: biomarkers, interventions, and challenges

The healthy gut microbiome is important in maintaining health and preventing various chronic and metabolic diseases through interactions with the host via different gut-organ axes, such as the gut-brain, gut-liver, gut-immune, and gut-lung axes. The human gut microbiome is relatively stable, yet can be influenced by numerous factors, such as diet, infections, chronic diseases, and medications which may disrupt its composition and function. Therefore, microbial resilience is suggested as one of the key characteristics of a healthy gut microbiome in humans. However, our understanding of its definition and indicators remains unclear due to insufficient experimental data. Here, we review the impact of key drivers including intrinsic and extrinsic factors such as diet and antibiotics on the human gut microbiome. Additionally, we discuss the concept of a resilient gut microbiome and highlight potential biomarkers including diversity indices and some bacterial taxa as recovery-associated bacteria, resistance genes, antimicrobial peptides, and functional flexibility. These biomarkers can facilitate the identification and prediction of healthy and resilient microbiomes, particularly in precision medicine, through diagnostic tools or machine learning approaches especially after antimicrobial medications that may cause stable dysbiosis. Furthermore, we review current nutrition intervention strategies to maximize microbial resilience, the challenges in investigating microbiome resilience, and future directions in this field of research.

Gerobiotics: Exploring the Potential and Limitations of Repurposing Probiotics in Addressing Aging Hallmarks and Chronic Diseases

As unhealthy aging continues to rise globally, there is a pressing need for effective strategies to promote healthy aging, extend health span, and address aging-related complications. Gerobiotics, an emerging concept in geroscience, offers a novel approach to repurposing selective probiotics, postbiotics, and parabiotics to modulate key aging processes and enhance systemic health. This review explores recent advancements in gerobiotics research, focusing on their role in targeting aging hallmarks, regulating longevity-associated pathways, and reducing risks of multiple age-related chronic conditions. Despite their promise, significant challenges remain, including optimizing formulations, ensuring safety and efficacy across diverse populations, and achieving successful clinical translation. Addressing these gaps through rigorous research, well-designed clinical trials, and advanced biotechnologies can establish gerobiotics as a transformative intervention for healthy aging and chronic disease prevention.

Glycaemic sugar metabolism and the gut microbiota: past, present and future

Non-communicable diseases (NCDs), such as type 2 diabetes (T2D) and metabolic dysfunction-associated fatty liver disease, have reached epidemic proportions worldwide. The global increase in dietary sugar consumption, which is largely attributed to the production and widespread use of cheap alternatives such as high-fructose corn syrup, is a major driving factor of NCDs. Therefore, a comprehensive understanding of sugar metabolism and its impact on host health is imperative to rise to the challenge of reducing NCDs. Notably, fructose appears to exert more pronounced deleterious effects than glucose, as hepatic fructose metabolism induces de novo lipogenesis and insulin resistance through distinct mechanisms. Furthermore, recent studies have demonstrated an intricate relationship between sugar metabolism and the small intestinal microbiota (SIM). In contrast to the beneficial role of colonic microbiota in complex carbohydrate metabolism, sugar metabolism by the SIM appears to be less beneficial to the host as it can generate toxic metabolites. These fermentation products can serve as a substrate for fatty acid synthesis, imposing negative health effects on the host. Nevertheless, due to the challenging accessibility of the small intestine, our knowledge of the SIM and its involvement in sugar metabolism remains limited. This review presents an overview of the current knowledge in this field along with implications for future research, ultimately offering potential therapeutic avenues for addressing NCDs.

Time-Resolved Evaluation of L-Dopa Metabolism in Bacteria-Host Symbiotic System and the Effect on Parkinson's Molecular Pathology

The gut microbiome influences drug metabolism and therapeutic efficacy. Still, the lack of a general label-free approach for monitoring bacterial or host metabolic contribution hampers deeper insights. Here, a 2D nuclear magnetic resonance (NMR) approach is introduced that enables real-time monitoring of the metabolism of Levodopa (L-dopa), an anti-Parkinson drug, in both live bacteria and bacteria-host (Caenorhabditis elegans) symbiotic systems. The quantitative method reveals that discrete Enterococcus faecalis substrains produce different amounts of dopamine in live hosts, even though they are a single species and all have the Tyrosine decarboxylase (TyrDC) gene involved in L-dopa metabolism. The differential bacterial metabolic activity correlates with differing Parkinson's molecular pathology concerning alpha-synuclein aggregation as well as behavioral phenotypes. The gene's existence or expression is not an indicator of metabolic activity is also shown, underscoring the significance of quantitative metabolic estimation in vivo. This simple approach is widely adaptable to any chemical drug to elucidate pharmacomicrobiomic relationships and may help rapidly screen bacterial metabolic effects in drug development.

Gut microbiota in multiple sclerosis and animal models

Multiple sclerosis (MS) is a chronic central nervous system (CNS) neurodegenerative and neuroinflammatory disease marked by a host immune reaction that targets and destroys the neuronal myelin sheath. MS and correlating animal disease models show comorbidities, including intestinal barrier disruption and alterations of the commensal microbiome. It is accepted that diet plays a crucial role in shaping the microbiota composition and overall gastrointestinal (GI) tract health, suggesting an interplay between nutrition and neuroinflammation via the gut-brain axis. Unfortunately, poor host health and diet lead to microbiota modifications that could lead to significant responses in the host, including inflammation and neurobehavioral changes. Beneficial microbial metabolites are essential for host homeostasis and inflammation control. This review will highlight the importance of the gut microbiota in the context of host inflammatory responses in MS and MS animal models. Additionally, microbial community restoration and how it affects MS and GI barrier integrity will be discussed.

Bridging gap in the treatment of Alzheimer's disease via postbiotics: Current practices and future prospects

Aging is an extremely significant risk associated with neurodegeneration. The most prevalent neurodegenerative disorders (NDs), such as Alzheimer's disease (AD) are distinguished by the prevalence of proteinopathy, aberrant glial cell activation, oxidative stress, neuroinflammation, defective autophagy, cellular senescence, mitochondrial dysfunction, epigenetic changes, neurogenesis suppression, increased blood-brain barrier permeability, and intestinal dysbiosis that is excessive for the patient's age. Substantial body studies have documented a close relationship between gut microbiota and AD, and restoring a healthy gut microbiota may reduce or even ameliorate AD symptoms and progression. Thus, control of the microbiota in the gut has become an innovative model for clinical management of AD, and rising emphasis is focused on finding new techniques for preventing and/or managing the disease. The etiopathogenesis of gut microbiota in driving AD progression and supplementing postbiotics as a preventive and therapeutic treatment for AD is discussed. The review additionally discusses the use of postbiotics in AD prophylaxis and therapy, portraying them as substances that address senescence-triggered dysfunctions and are worthy of translating from bench to biopharmaceutical market in response to "silver consumers" needs. The current review examines and evaluates the impact of postbiotics as whole and specific metabolites, such as short-chain fatty acids (SCFAs), lactate, polyamines, polyphenols, tryptophan metabolites, exopolysaccharides, and bacterial extracellular vesicles, on the aging-associated processes that reinforce AD. Moreover, it provides an overview of the most recent data from both clinical and preclinical research involving the use of postbiotics in AD.

Nanotechnology-driven EGCG: bridging antioxidant and therapeutic roles in metabolic and cancer pathways

Epigallocatechin-3-gallate (EGCG), the primary polyphenol in green tea, is renowned for its potent antioxidant properties. EGCG interacts with various cellular targets, inhibiting cancer cell proliferation through apoptosis and cell cycle arrest induction, while also modulating metabolic pathways. Studies have demonstrated its potential in addressing cancer development, obesity, and diabetes. Given the rising prevalence of metabolic diseases and cancers, EGCG is increasingly recognized as a promising therapeutic agent. This review provides a comprehensive overview of the latest findings on the effects of both free and nano-encapsulated EGCG on mechanisms involved in the management and prevention of hyperlipidemia, diabetes, and gastrointestinal (GI) cancers. The review highlights EGCG role in modulating key signaling pathways, enhancing bioavailability through nano-formulations, and its potential applications in clinical settings.

The Gut Microbiota and Colorectal Cancer: Understanding the Link and Exploring Therapeutic Interventions

CRC remains a significant public health challenge due to its high prevalence and mortality rates. Emerging evidence highlights the critical role of the gut microbiota in both the pathogenesis of CRC and the efficacy of treatment strategies, including chemotherapy and immunotherapy. Dysbiosis, characterized by imbalances in microbial communities, has been implicated in CRC progression and therapeutic outcomes. This review examines the intricate relationship between gut microbiota composition and CRC, emphasizing the potential for microbial profiles to serve as biomarkers for early detection and prognosis. Various interventions, such as prebiotics, probiotics, postbiotics, fecal microbiota transplantation, and dietary modifications, aim to restore microbiota balance and shift dysbiosis toward eubiosis, thereby improving health outcomes. Additionally, the integration of microbial profiling into clinical practice could enhance diagnostic capabilities and personalize treatment strategies, advancing the field of oncology. The study of intratumoral microbiota offers new diagnostic and prognostic tools that, combined with artificial intelligence algorithms, could predict treatment responses and assess the risk of adverse effects. Given the growing understanding of the gut microbiome-cancer axis, developing microbiota-oriented strategies for CRC prevention and treatment holds promise for improving patient care and clinical outcomes.

Unveiling the Important Role of Gut Microbiota and Diet in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS), characterized by neurodegeneration, axonal damage, demyelination, and inflammation. Recently, gut dysbiosis has been linked to MS and other autoimmune conditions. Namely, gut microbiota has a vital role in regulating immune function by influencing immune cell development, cytokine production, and intestinal barrier integrity. While balanced microbiota fosters immune tolerance, dysbiosis disrupts immune regulation, damages intestinal permeability, and heightens the risk of autoimmune diseases. The critical factor in shaping the gut microbiota and modulating immune response is diet. Research shows that high-fat diets rich in saturated fats are associated with disease progression. Conversely, diets rich in fruits, yogurt, and legumes may lower the risk of MS onset and progression. Specific dietary interventions, such as the Mediterranean diet (MD) and ketogenic diet, have shown potential to reduce inflammation, support neuroprotection, and promote CNS repair. Probiotics, by restoring microbial balance, may also help mitigate immune dysfunction noted in MS. Personalized dietary strategies targeting the gut microbiota hold promise for managing MS by modulating immune responses and slowing disease progression. Optimizing nutrient intake and adopting anti-inflammatory diets could improve disease control and quality of life. Understanding gut-immune interactions is essential for developing tailored nutritional therapies for MS patients.

Biotransformation of Ganoderma lucidum and Hericium erinaceus for ex vivo gut-brain axis modulation and mood-related outcomes in humans: CREB/BDNF signaling and microbiota-driven synergies

BACKGROUND

The human gut microbiota plays a crucial role in various aspects of health, extending beyond digestion and nutrient absorption. Ganoderma lucidum (Reishi) and Hericium erinaceus (Lion's Mane), traditional medicinal mushrooms, have garnered interest due to their potential to exert positive health effects. The aim of our study was to investigate the molecular impact of Reishi and Lion's Mane on mood regulation through the gut-brain axis.

METHODS

We utilized a dynamic simulator of the human intestinal microbial ecosystem (SHIME), followed by HPLC-ESI-QTOF-MS/MS and a series of biochemical and molecular assays, including MTT for cell viability, fluorogenic probes for redox balance (ROS and GSH), and Western blot for protein analysis.

RESULTS

Chromatographic analysis confirmed the presence of bioactive compounds in both mushrooms, including triterpenoids (ganoderic acids) and polysaccharides in G. lucidum, as well as hericenones and erinacines in H. erinaceus. We observed concentration-dependent changes in metabolic activity and redox balance due to microbiome cell-free supernatant treatment (M-CFSs). M-CFSs also influenced the Nrf2 pathway and activated heat shock proteins, which may confer neuroprotective effects. Notably, M-CFSs upregulated neurotrophic factors such as BDNF, CDNF, and MANF, crucial for neuronal function. Our study revealed alterations in intracellular signaling cascades, most notably the CREB/BDNF pathway. Moreover, the Akt/mTOR and ERK1/2 showed no significant changes, while Akt/GSK3α/β displayed only partial modifications. The overlapping effects of synaptic activity and activation of the gut-brain axis appear to contribute to mood enhancement.

CONCLUSIONS

These pilot findings suggest a potential role for G. lucidum and H. erinaceus in mood disorder regulation through multifaceted mechanisms involving the gut microbiota. The study underscores the importance of understanding the synergistic interactions between medicinal fungi, gut microbiota, and neural processes to develop novel or preventive strategies for mental health disorders.