Mechanisms and consequences of intestinal dysbiosis

Interkingdom signaling between gastrointestinal hormones and the gut microbiome

The interplay between the gut microbiota and gastrointestinal hormones plays a pivotal role in the health of the host and the development of diseases. As a vital component of the intestinal microecosystem, the gut microbiota influences the synthesis and release of many gastrointestinal hormones through mechanisms such as modulating the intestinal environment, producing metabolites, impacting mucosal barriers, generating immune and inflammatory responses, and releasing neurotransmitters. Conversely, gastrointestinal hormones exert feedback regulation on the gut microbiota by modulating the intestinal environment, nutrient absorption and utilization, and the bacterial biological behavior and composition. The distributions of the gut microbiota and gastrointestinal hormones are anatomically intertwined, and close interactions between the gut microbiota and gastrointestinal hormones are crucial for maintaining gastrointestinal homeostasis. Interventions leveraging the interplay between the gut microbiota and gastrointestinal hormones have been employed in the clinical management of metabolic diseases and inflammatory bowel diseases, such as bariatric surgery and fecal microbiota transplantation, offering promising targets for the treatment of dysbiosis-related diseases.

Microbial diversity and fitness in the gut-brain axis: influences on developmental risk for Alzheimer's disease

The gut-brain axis (GBA) denotes the dynamic and bidirectional communication system that connects the gastrointestinal tract and the central nervous system (CNS). This review explored this axis, focusing on the role of microbial diversity and fitness in maintaining gastrointestinal health and preventing neurodegeneration, particularly in Alzheimer's disease (AD). Gut dysbiosis, characterized by the imbalance in populations of beneficial and harmful bacteria, has been associated with increased systemic inflammation, neuroinflammation, and the progression of AD through pathogenic mechanisms involving amyloid deposition, tauopathy, and increased blood-brain barrier (BBB) permeability. Emerging evidence highlighted the therapeutic potential of probiotics, dietary interventions, and intermittent fasting in restoring microbial balance, reducing inflammation, and minimizing neurodegenerative risks. Probiotics and synbiotics are promising in helping improve cognitive function and metabolic health, while dietary patterns like the Mediterranean diet were linked to decreased neuroinflammation and enhanced gut-brain communication. Despite significant advancement, further research is needed to elucidate the specific microbial strains, metabolites, and mechanisms influencing brain health. Future studies employing longitudinal designs and advanced omics technologies are essential to developing targeted microbiome-based therapies for managing AD-related disorders.

Gut Microbiota Dysbiosis: Pathogenesis, Diseases, Prevention, and Therapy

Dysbiosis refers to the disruption of the gut microbiota balance and is the pathological basis of various diseases. The main pathogenic mechanisms include impaired intestinal mucosal barrier function, inflammation activation, immune dysregulation, and metabolic abnormalities. These mechanisms involve dysfunctions in the gut-brain axis, gut-liver axis, and others to cause broader effects. Although the association between diseases caused by dysbiosis has been extensively studied, many questions remain regarding the specific pathogenic mechanisms and treatment strategies. This review begins by examining the causes of gut microbiota dysbiosis and summarizes the potential mechanisms of representative diseases caused by microbiota imbalance. It integrates clinical evidence to explore preventive and therapeutic strategies targeting gut microbiota dysregulation, emphasizing the importance of understanding gut microbiota dysbiosis. Finally, we summarized the development of artificial intelligence (AI) in the gut microbiota research and suggested that it will play a critical role in future studies on gut dysbiosis. The research combining multiomics technologies and AI will further uncover the complex mechanisms of gut microbiota dysbiosis. It will drive the development of personalized treatment strategies.

Microbiota, mitochondria, and epigenetics in health and disease: converging pathways to solve the puzzle

Dysbiosis, which refers to an imbalance in the composition of the gut microbiome, has been associated with a range of metabolic disorders, including type 2 diabetes, obesity, and metabolic syndrome. Although the exact mechanisms connecting gut dysbiosis to these conditions are not fully understood, various lines of evidence strongly suggest a substantial role for the interaction between the gut microbiome, mitochondria, and epigenetics. Current studies suggest that the gut microbiome has the potential to affect mitochondrial function and biogenesis through the production of metabolites. A well-balanced microbiota plays a pivotal role in supporting normal mitochondrial and cellular functions by providing metabolites that are essential for mitochondrial bioenergetics and signaling pathways. Conversely, in the context of illnesses, an unbalanced microbiota can impact mitochondrial function, leading to increased aerobic glycolysis, reduced oxidative phosphorylation and fatty acid oxidation, alterations in mitochondrial membrane permeability, and heightened resistance to cellular apoptosis. Mitochondrial activity can also influence the composition and function of the gut microbiota. Because of the intricate interplay between nuclear and mitochondrial communication, the nuclear epigenome can regulate mitochondrial function, and conversely, mitochondria can produce metabolic signals that initiate epigenetic changes within the nucleus. Given the epigenetic modifications triggered by metabolic signals from mitochondria in response to stress or damage, targeting an imbalanced microbiota through interventions could offer a promising strategy to alleviate the epigenetic alterations arising from disrupted mitochondrial signaling.

The human microbiome: redefining cancer pathogenesis and therapy

The human microbiome has always been an important determinant of health and recently, its role has also been described in cancer. The altered microbiome could aid cancer progression, modulate chemoresistance and significantly alter drug efficacy. The broad implications of microbes in cancer have prompted researchers to investigate the microbe-cancer axis and identify whether modifying the microbiome could sensitize cancer cells for therapy and improve the survival outcome of cancer patients. The preclinical data has shown that enhancing the number of specific microbial species could restore the patients' response to cancer drugs and the microbial biomarkers may play a vital role in cancer diagnostics. The elucidation of detailed interactions of the human microbiota with cancer would not only help identify the novel drug targets but would also enhance the efficacy of existing drugs. The field exploring the emerging roles of microbiome in cancer is at a nascent stage and an in-depth scientific perspective on this topic would make it more accessible to a wider audience. In this review, we discuss the scientific evidence connecting the human microbiome to the origin and progression of cancer. We also discuss the potential mechanisms by which microbiota affects initiation of cancer, metastasis and chemoresistance. We highlight the significance of the microbiome in therapeutic outcome and evaluate the potential of microbe-based cancer therapy.

Development of antibiotic resistome in premature infants

Preterm birth is a major concern in neonatal care, significantly impacting infant survival and long-term health. The gut microbiome, essential for infant development, often becomes imbalanced in preterm infants, making it crucial to understand the effects of antibiotics on its development. Our study analyzed weekly, 6-month, and 1-year stool samples from 100 preterm infants, correlating clinical data on antibiotic use and feeding patterns. Comparing infants who received no antibiotics with those given empirical post-birth treatment, we observed notable alterations in the gut microbiome's composition and an increase in antibiotic resistance gene abundance early in life. Although these effects diminished over time, their long-term clinical impacts remain unclear. Human milk feeding was associated with beneficial microbiota like Actinobacteriota and reduced antibiotic resistance genes, underscoring its protective role. This highlights the importance of judicious antibiotic use and promoting human milk to foster a healthy gut microbiome in preterm infants.

MyD88-mediated signaling in intestinal fibroblasts regulates macrophage antimicrobial defense and prevents dysbiosis in the gut

Fibroblasts that reside in the gut mucosa are among the key regulators of innate immune cells, but their role in the regulation of the defense functions of macrophages remains unknown. MyD88 is suggested to shape fibroblast responses in the intestinal microenvironment. We found that mice lacking MyD88 in fibroblasts showed a decrease in the colonic antimicrobial defense, developing dysbiosis and aggravated dextran sulfate sodium (DSS)-induced colitis. These pathological changes were associated with the accumulation of Arginase 1+ macrophages with low antimicrobial defense capability. Mechanistically, the production of interleukin (IL)-6 and CCL2 downstream of MyD88 was critically involved in fibroblast-mediated support of macrophage antimicrobial function, and IL-6/CCL2 neutralization resulted in the generation of macrophages with decreased production of the antimicrobial peptide cathelicidin and impaired bacterial clearance. Collectively, these findings revealed a critical role of fibroblast-intrinsic MyD88 signaling in regulating macrophage antimicrobial defense under colonic homeostasis, and its disruption results in dysbiosis, predisposing the host to the development of intestinal inflammation.

Distribution of gut microbiota across intestinal segments and their impact on human physiological and pathological processes

In recent years, advancements in metagenomics, metabolomics, and single-cell sequencing have enhanced our understanding of the intricate relationships between gut microbiota and their hosts. Gut microbiota colonize humans from birth, with their initial composition significantly influenced by the mode of delivery and feeding method. During the transition from infancy to early childhood, exposure to a diverse diet and the maturation of the immune system lead to the gradual stabilization of gut microbiota's composition and distribution. Numerous studies have demonstrated that gut microbiota can influence a wide range of physiological functions and pathological processes by interacting with various tissues and organs through the gut-organ axis. Different intestinal segments exhibit unique physical and chemical conditions, which leads to the formation of vertical gradients along the intestinal tract: aerobes and facultative aerobes mainly live in the small intestine and anaerobic bacteria mainly live in the large intestine, and horizontal gradients: mucosa-associated microbiota and lumen-associated microbiota. In this review, we systematically summarize the distribution characteristics of gut microbiota across six intestinal segments: duodenum, jejunum, ileum, cecum, colon, and rectum. We also draw a conclusion that gut microbiota distributed in different intestinal segments affect the progression of different diseases. We hope to elucidate the role of microbiota at specific anatomic sites within the gut in precisely regulating the processes of particular diseases, thereby providing a solid foundation for developing novel diagnostic and therapeutic strategies for related diseases.

Recent Advances in Gut Microbiota in Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory disease characterized by joint inflammation and skin lesions. Recent research has underscored the critical role of gut microbiota-comprising bacteria, fungi, viruses, and archaea-in the pathogenesis and progression of PsA. This narrative review synthesizes the latest findings on the influence of gut microbiota on PsA, focusing on mechanisms such as immune modulation, microbial dysbiosis, the gut-joint axis, and its impact on treatment. Advances in high-throughput sequencing and metagenomics have revealed distinct microbial profiles associated with PsA. Studies show that individuals with PsA have a unique gut microbiota composition, differing significantly from healthy controls. Alterations in the abundance of specific bacterial taxa, including a decrease in beneficial bacteria and an increase in potentially pathogenic microbes, contribute to systemic inflammation by affecting the intestinal barrier and promoting immune responses. This review explores the impact of various factors on gut microbiota composition, including age, hygiene, comorbidities, and medication use. Additionally, it highlights the role of diet, probiotics, and fecal microbiota transplantation as promising strategies to modulate gut microbiota and alleviate PsA symptoms. The gut-skin-joint axis concept illustrates how gut microbiota influences not only gastrointestinal health but also skin and joint inflammation. Understanding the complex interplay between gut microbiota and PsA could lead to novel, microbiome-based therapeutic approaches. These insights offer hope for improved patient outcomes through targeted manipulation of the gut microbiota, enhancing both diagnosis and treatment strategies for PsA.

The Gut-Heart Axis and Its Role in Doxorubicin-Induced Cardiotoxicity: A Narrative Review

Doxorubicin is a widely used chemotherapy for the treatment of several types of cancer. However, its application is restricted due to adverse effects, particularly cardiotoxicity, which can progress to heart failure-a chronic and debilitating condition. Several mechanisms have been identified in the pathophysiology of doxorubicin-induced cardiotoxicity, including oxidative stress, mitochondrial dysfunction, inflammation, and disruption of collagen homeostasis. More recently, dysbiosis of the gut microbiota has been implicated in the development and perpetuation of cardiac injury. Studies have reported alterations in the composition and abundance of the microbiota during doxorubicin treatment. Therefore, as of recent, there is a new field of research in order to develop strategies involving the gut microbiota to prevent or attenuate cardiotoxicity since there is no effective therapy at the moment. This narrative review aims to provide an update on the role of gut microbiota and intestinal permeability in the pathophysiology of cardiovascular diseases, and more specifically doxorubicin-induced cardiotoxicity. Additionally, it seeks to establish a foundation for future research targeting gut microbiota to alleviate cardiotoxicity.

Should We Treat SIBO Patients? Impact on Quality of Life and Response to Comprehensive Treatment: A Real-World Clinical Practice Study

Background: Small intestinal bacterial overgrowth (SIBO) is a dysbiosis marked by an excessive proliferation of bacteria in the small intestine, resulting in abdominal symptoms that significantly affect patients' quality of life. Objectives: This study aims to evaluate the impact of a comprehensive therapeutic approach in improving the quality of life of patients with SIBO. Methods: For this purpose, standardized questionnaires were used at baseline, 30 days and 90 days, including the IBS-QOL (Irritable Bowel Syndrome Quality of Life Questionnaire), the GSRS (Gastrointestinal Symptom Rating Scale), the EuroQOL-5D, and the Bristol Scale. Results: The results show that a comprehensive approach, combining pharmacological treatment, appropriate dietary intervention, and strategies aimed at improving gut microbiota and intestinal permeability, produces a sustained improvement in the quality of life of a significant proportion of patients who participated in the study. Furthermore, the results suggest that, although gas normalization is a relevant indicator, clinical improvement and quality of life depend considerably on patients' subjective perception of their health. Conclusions: This finding underscores the importance of recognizing SIBO as a prevalent condition that requires accurate diagnoses and individualized treatments to improve patients' well-being.

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.

Probiotics for the treatment of hyperlipidemia: Focus on gut-liver axis and lipid metabolism

Hyperlipidemia, a metabolic disorder marked by dysregulated lipid metabolism, is a key contributor to the onset and progression of various chronic diseases. Maintaining normal lipid metabolism is critical for health, as disruptions lead to dyslipidemia. The gut and liver play central roles in lipid homeostasis, with their bidirectional communication, known as the gut-liver axis, modulated by bile acids (BAs), gut microbiota, and their metabolites. BAs are essential for regulating their own synthesis, lipid metabolism, and anti-inflammatory responses, primarily through the farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5). Available evidence suggests that high-fat diet-induced the gut microbiota dysbiosis can induce "leaky gut," allowing toxic microbial metabolites to enter the liver via portal circulation, triggering liver inflammation and lipid metabolism disturbances, ultimately leading to hyperlipidemia. Extensive studies have highlighted the roles of probiotics and Traditional Chinese Medicine (TCM) in restoring gut-liver axis balance and modulating lipid metabolism through regulating the levels of lipopolysaccharides, short-chain fatty acids, and BAs. However, the therapeutic potential of probiotics and TCM for hyperlipidemia remains unclear. Here, firstly, we explore the intricate interplay among gut microbiota and metabolites, lipid metabolism, gut-liver axis, and hyperlipidemia. Secondly, we summarize the mechanisms by which probiotics and TCM can alleviate hyperlipidemia by altering the composition of gut microbiota and regulating lipid metabolism via the gut-liver axis. Finally, we emphasize that more clinical trials of probiotics and TCM are necessary to examine their effects on lipid metabolism and hyperlipidemia.

The stomach, small intestine, and colon-specific gastrointestinal tract delivery systems for bioactive nutrients

Oral administration is a convenient way to deliver bioactive nutrients. However, the complex and dynamic environment of the gastrointestinal (GI) tract poses distinct challenges. These include the acidic environment of the stomach, limited transport across the GI mucosa, and the risk of enzymatic degradation, all of which can compromise the nutritional effectiveness of orally delivered nutrients. In response to these challenges, various GI tract delivery systems have been developed to target specific regions, such as the stomach, small intestine, or colon, to precisely control the release of bioactive nutrients and enhance their health-promoting benefits. This review critically examines the principles underlying stomach-, small intestine-, and colon-targeted delivery systems, highlighting the selection of appropriate wall materials and the interactions between delivery systems and the mucosal epithelial barrier. Moreover, we describe relevant biological models and quantitative analyses to measure these interactions. In particular, we emphasize the significant advantages offered by colon-targeted delivery systems in maintaining a healthy colonic microenvironment. This review aims to inspire novel concepts and stimulate further research into GI tract delivery systems, offering promising avenues for maximizing the therapeutic effects of bioactive nutrients in practical applications.

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.

Sirtuins and Gut Microbiota: Dynamics in Health and a Journey from Metabolic Dysfunction to Hepatocellular Carcinoma

Metabolic dysfunction leading to non-alcoholic fatty liver disease (NAFLD) exhibits distinct molecular and immune signatures that are influenced by factors like gut microbiota. The gut microbiome interacts with the liver via a bidirectional relationship with the gut-liver axis. Microbial metabolites, sirtuins, and immune responses are pivotal in different metabolic diseases. This extensive review explores the complex and multifaceted interrelationship between sirtuins and gut microbiota, highlighting their importance in health and disease, particularly metabolic dysfunction and hepatocellular carcinoma (HCC). Sirtuins (SIRTs), classified as a group of NAD+-dependent deacetylases, serve as crucial modulators of a wide spectrum of cellular functions, including metabolic pathways, the inflammatory response, and the process of senescence. Their subcellular localization and diverse functions link them to various health conditions, including NAFLD and cancer. Concurrently, the gut microbiota, comprising diverse microorganisms, significantly influences host metabolism and immune responses. Recent findings indicate that sirtuins modulate gut microbiota composition and function, while the microbiota can affect sirtuin activity. This bidirectional relationship is particularly relevant in metabolic disorders, where dysbiosis contributes to disease progression. The review highlights recent findings on the roles of specific sirtuins in maintaining gut health and their implications in metabolic dysfunction and HCC development. Understanding these interactions offers potential therapeutic avenues for managing diseases linked to metabolic dysregulation and liver pathology.

Role of gut microbiota in thalassemia: a review of therapeutic prospects

In recent years, the study of gut microbiota has gradually become a research hotspot in the field of medicine, as gut microbiota dysbiosis is closely related to various diseases. Thalassemia, as a hereditary hemoglobinopathy, has a complex pathophysiological mechanism, and traditional treatment methods show limited efficacy. With a deeper understanding of the gut microbiome, researchers have begun to focus on its role in the pathogenesis of thalassemia and its therapeutic effects. This article aims to review the role of gut microbiota in thalassemia and its potential therapeutic prospects, analyze the latest research findings, and explore the impact and mechanisms of gut microbiota on patients with thalassemia, with the goal of providing new ideas and directions for future research and clinical treatment of thalassemia.

Role of the oral-gut microbiota axis in pancreatic cancer: a new perspective on tumor pathophysiology, diagnosis, and treatment

Pancreatic cancer, one of the most lethal malignancies, remains challenging due to late diagnosis, aggressive progression, and therapeutic resistance. Recent advances have revealed the presence of intratumoral microbiota, predominantly originating from the oral and gut microbiomes, which play pivotal roles in pancreatic cancer pathogenesis. The dynamic interplay between oral and gut microbial communities, termed the "oral-gut microbiota axis," contributes multifacetedly to pancreatic ductal adenocarcinoma (PDAC). Microbial translocation via anatomical or circulatory routes establishes tumor-resident microbiota, driving oncogenesis through metabolic reprogramming, immune regulation, inhibition of apoptosis, chronic inflammation, and dysregulation of the cell cycle. Additionally, intratumoral microbiota promote chemoresistance and immune evasion, further complicating treatment outcomes. Emerging evidence highlights microbial signatures in saliva and fecal samples as promising non-invasive diagnostic biomarkers, while microbial diversity correlates with prognosis. Therapeutic strategies targeting this axis-such as antibiotics, probiotics, and engineered bacteria-demonstrate potential to enhance treatment efficacy. By integrating mechanisms of microbial influence on tumor biology, drug resistance, and therapeutic applications, the oral-gut microbiota axis emerges as a critical regulator of PDAC, offering novel perspectives for early detection, prognostic assessment, and microbiome-based therapeutic interventions.

National analysis of the dietary index for gut microbiota and kidney stones: evidence from NHANES (2007-2018)

Background

Previous studies have highlighted the effects of diet and gut microbiota on the incidence of kidney stones, and the dietary index for gut microbiota (DI-GM) is a new dietary index that accurately represents the variety of gut microbiota. The current study intends to examine the potential correlation between DI-GM and kidney stones.

Methods

Data from the 2007-2018 National Health and Nutrition Examination Survey (NHANES) were employed in this cross-sectional study. The history of kidney stones was assessed using a kidney conditions questionnaire. In order to examine the correlation between DI-GM and kidney stones, multivariate logistic regression was implemented. Additionally, smoothed curve fitting, subgroup analyses, and sensitivity analyses were conducted.

Results

The investigation encompassed a total of 21,587 participants. After adjusting for all potential covariates, we found that DI-GM was negatively related to the incidence of kidney stones (OR = 0.96, 95% CI = 0.93-0.98, p = 0.0021). Compared to those in the lowest quartile, participants in the highest quartile had a lower prevalence of kidney stones (OR = 0.86, 95% CI = 0.75-0.98, p = 0.0252). Additionally, smoothed curve fitting revealed that DI-GM was linearly associated with the incidence of kidney stones. The results of the sensitivity analyses proved the robustness of the main analyses.

Conclusion

A negative correlation between the incidence of kidney stones and DI-GM is supported by the evidence presented in this study. This finding emphasizes the potential benefits of adjusting dietary structure according to DI-GM in reducing the incidence of kidney stones. Further research should validate this discovery by employing longitudinal studies.

Proline rich-39 (PR-39) antimicrobial protein alleviated lipopolysaccharide-induced intestinal barrier dysfunction in piglets by altering intestinal flora associated bile acid metabolism and in turn regulating TGR-5/NF-κB/MLCK/MLC pathway

Proline rich-39 (PR-39) is a natural antimicrobial protein with good antibacterial and anti-inflammatory activities. The miniature Wuzhishan pig (WZSP) has important similarities to humans in anatomical structure, physiological characteristics, and nutrient metabolism that make it an important model animal for biomedical research. This study aimed to investigate the protective effect and therapeutic mechanism of PR-39 on intestinal barrier function using the LPS-induced enteritis model in WZSPs. We found that PR-39 treatment reversed the decrease in growth performance and peripheral organ damage, regulated serum indices (IL-1β, IL-6, TNF-α, IL-10, TGF-β, IgA, IgG, DAO, D-LA) and enhanced the antioxidant capacity (MDA, CAT, GSH-Px, T-AOC) of piglets. PR-39 protected the integrity of the jejunal barrier by upregulating the density of goblet cells and the expression of tight junction proteins ZO-1, Claudin-1, and Occludin. Additionally, PR-39 increased the abundance of jejunal probiotics (e.g., Lactococcus), and increased the cecal abundance of Lactobacillus johnsonii, then promoted the production of 7-keto deoxycholic acid to activate the bile acid receptor TGR5, which in turn inhibited the NF-κB-MLCK-MLC signaling pathway and the secretion of proinflammatory factors by macrophages. In summary, these findings suggest that PR-39 supplementation may be an effective strategy to improve the intestinal damage and dysfunction.

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.

Modulating effects of mycotoxin and oxidized oil on intestinal microbiota in broiler chickens

Climatic change and increased use of alternative sources of feed ingredients could influence poultry production. Mycotoxin and oxidized oil are two contaminations that may occur in chicken feed as a result of climate change and use of alternative feed ingredients, and these factors may have differential and potentially additive effects on birds' intestinal microbiota. The study objective was to determine the main effects of corn, oil quality, and their interaction on ileal content, ileal scrapings, cecal content, and whole cecum (content and tissue) microbiota in broiler chickens. Broiler chickens were raised for 21 days post-hatch and fed diet made with regular or mycotoxin-contaminated corn (7,959 ppb of deoxynivalenol, 2.1 ppm of aflatoxin, 23,200 ppb of fumonisin, and 1,403 ppb of zearalenone), and regular or oxidized (148 meq/kg) oil. Bacterial genomic DNA was extracted and sequenced targeting the variable (V3-V4) region of the 16S gene. The bioinformatic and statistical analysis of the microbiota data showed mycotoxin and mycotoxin by oxidized oil interaction increased the richness and evenness in the ileal content and only evenness in the cecal content. Mycotoxin and mycotoxin by oxidized oil interaction also increased beta diversity based on the variability in microbial community in the ileal content while increasing the abundance of bacterial taxa, including Streptomyces and Escherichia-Shigella, and predicted pathways related to RNA and DNA synthesis (Mycothiol and pyrimidine deoxyribonucleotides synthesis) and redox regulation (ergothioneine biosynthesis) in ileal content and pathways related to glycol metabolism and degradation and amino acids degradation were increased in the cecal content. Streptomyces has been associated with mycotoxin detoxication, and its increase could reduce the negative effects of mycotoxins contrary to Escherichia-Shigella, which has been negatively correlated with weight gain in chickens. These results show that mycotoxin alone and its combination with oxidized oil affect bacterial diversity and abundance mostly in the ileum content and predicted metabolic pathways across intestinal sections.

The Critical Role of Faecalibacterium prausnitzii in Cardiovascular Diseases

Due to the continued aging of the global population, cardiovascular diseases (CVDs) remain the main cause of death worldwide, with millions of fatalities from diseases, including stroke and coronary artery disease, reported annually. Thus, novel therapeutic approaches and targets are urgently required for diagnosing and treating CVDs. Recent studies emphasize the vital part of gut microbiota in both CVD prevention and management. Among these, Faecalibacterium prausnitzii (F. prausnitzii) has emerged as a promising probiotic capable of improving intestinal health. Although preliminary investigations demonstrate that F. prausnitzii positively enhances cardiovascular health, research specifically connecting this strain to CVD outcomes remains limited. Based on current research and assessment of possible clinical applications, this paper aimed to investigate the positive effects on cardiovascular health using F. prausnitzii and its metabolites. Targeting gut flora is expected to become a mainstay in CVD treatment as research develops.

The major roles of intestinal microbiota and TRAF6/NF-κB signaling pathway in acute intestinal inflammation in mice, and the improvement effect by Hippophae rhamnoides polysaccharide

Acute enteritis, an intestinal disease with intestinal inflammation and injury as the main pathological manifestations. Inhibiting the inflammatory response is critical to the treatment of acute enteritis. Previous studies have shown that the Hippophae rhamnoides polysaccharide (HRP) has strong immune-enhancing effects. However, their functions regarding the intestines and the underlying mechanism are still unclear. In this study, the role of HRP in lipopolysaccharide (LPS)-induced acute enteritis in mice and its related mechanisms are discussed from two aspects: intestinal inflammation and intestinal microbiota. Kunming mice were inoculated with LPS to establish animal models of acute enteritis. The results showed that HRP attenuated the histological damage and maintained the intestine mucosal barrier via up-regulating the expression of occludin, claudin-1, and zona occludens-1 (ZO-1), and suppressing the levels of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β)). The relative mRNA and protein levels of nuclear factor-kappa B p65 (NF-κBp65) and tumor necrosis factor-receptor-associated factor 6 (TRAF6) in the intestine tissues of LPS-induced acute enteritis mice significantly increased, whereas these adverse changes were alleviated in the HRP intervention groups. Notably, HRP may regulate the expression of the TRAF6/NF-κB signaling pathway by affecting the diversity of the intestinal microbiota. Microbiota analysis showed that HRP promoted the proliferation of beneficial bacteria, including Clostridia_UCG-014, Candidatus_Saccharimonas, Lachnospiraceae_NK4A136_group, Bacteroidota, Deferribacterota, and reduced the abundance of Atopostipes, Corynebacterium, Actinobacteriota, and Desulfobacterota. The studies conformed that the gut microbiota is crucial in HRP-mediated immunity regulation. HRP shows great potential as an immune enhancer and a natural medicine for treating intestinal inflammatory diseases.

Maternal protein restriction impairs intestinal morphophysiology and antioxidant system in young male offspring rats

The developmental origins of health and disease (DOHaD) concept suggests that adverse conditions during gestation can influence the development and function of multiple organs, including the gastrointestinal tract. Maternal protein restriction (MPR) exposure has been associated with negative effects on reproduction, the endocrine system, and liver metabolic health. However, limited research has explored the impact of MPR on the offspring's intestinal morphophysiology. This study investigated the effects of gestational and lactational MPR on the duodenum and colon of young male offspring rats at postnatal (PND)21. We hypothesize that MPR affects intestinal morphophysiology and development early in life. Our findings revealed tachygastria in offspring exposed to MPR. The ultrastructural analysis uncovered a reduction in goblet cell numbers and changes in collagen deposition in the duodenum and colon. We also identified imbalances in inflammatory markers (IL-6 and TGF-β1) and antioxidant enzymes (CAT and SOD). These results demonstrate that MPR significantly affects gastrointestinal morphophysiology early in life by disrupting gastric motility and altering duodenal and colonic histoarchitecture, antioxidant defense, and inflammatory pathways. Such alterations may predispose the descendants to long-term gastrointestinal disorders, underscoring the importance of further research on the developmental origins of intestinal health and disease.

Harnessing the Power of Donkey's Milk and Homemade Pickles: Unveiling Oxalate-Degrading Probiotics and Their Heat-Killed Cells as Antiadipogenic Agents in 3T3-L1 Adipocytes

Gut microbial dysbiosis is associated with the development of critical clinical conditions of metabolic syndrome (obesity, type II diabetes), and calcium oxalate kidney stones. The human gut microbial eubiosis with functional probiotics and their heat-killed cells of lactic acid bacteria (LAB) is considered the current therapy for metabolic syndrome (MS). In accordance with this, our study aimed to isolate oxalate-degrading, cholesterol-lowering, and anti-adipogenic bacterial strains from raw donkey's milk and homemade fermented pickles. Nine LAB strains with potential in vitro oxalate degrading, α-glucosidase inhibiting, and cholesterol-lowering activities were pre-screened from fourteen isolates. Further, the heat-killed cells of selected strains were evaluated for anti-adipogenic activity in murine 3T3-L1 adipocytes. This activity was examined by studying the lipid storage, gene, and protein expression of adipogenic and lipogenic transcription factors. Subsequently, four potential isolates demonstrated a significant reduction in lipid storage by limiting adipogenesis (reducing C/EBPα, PPARγ expression), lipid transportation (downregulating aP2 expression), and lipogenesis (reducing PLIN-1 expression). These effective isolates were characterized using 16S rRNA molecular sequencing, and were identified as closest relatives to the Enterococcus (RRLA5, RRLA1, and RRLD6) and Lactobacillus (RRLM2) genera. Further, they displayed good survivability under in vitro gastric conditions and non-haemolytic activity. Taken together, the live cells of effective isolates depicted significant in vitro oxalate degradation, and their heat-killed cells demonstrated anti-adipogenic activity through downregulating the adipogenesis and lipogenesis. Moreover, future preclinical animal model studies on the synergistic role of probiotics and their heat-killed cells in disease prevention through gut microbial modulation could provide evidence as a biotherapeutic agent.

The Complex Role of Gut Microbiota in Systemic Lupus Erythematosus and Lupus Nephritis: From Pathogenetic Factor to Therapeutic Target

The role of gut microbiota (GM) and intestinal dysbiosis in triggering the onset and/or modulating the severity and progression of lupus nephritis (LN) has been the object of intense research over the last few years. Some alterations at the phyla level, such as the abundance of Proteobacteria and reduction in Firmicutes/Bacteroidetes (F/B) ratio and in α-diversity have been consistently reported in systemic lupus erythematosus (SLE), whereas a more specific role has been ascribed to some species (Bacteroides thetaiotaomicron and Ruminococcus gnavus) in LN. Underlying mechanisms include microbial translocation through a "leaky gut" and subsequent molecular mimicry, immune dysregulation (alteration of IFNγ levels and of balance between Treg and Th17 subsets), and epigenetic interactions. Levels of bacterial metabolites, such as butyrate and other short-chain fatty acids (SCFAs), appear to play a key role in modulating LN. Beyond bacterial components of GM, virome and mycobiome are also increasingly recognized as important players in the modulation of an immune response. On the other hand, microbiota-based therapy appears promising and includes diet, prebiotics, probiotics, symbiotics, and fecal microbiota transplantation (FMT). The modulation of microbiota could correct critical alterations, such as F/B ratio and Treg/Th17 imbalance, and blunt production of autoantibodies and renal damage. Despite current limits, GM is emerging as a powerful environmental factor that could be harnessed to interfere with key mechanisms leading to SLE, preventing flares and organ damage, including LN. The aim of this review is to provide a state-of-the-art analysis of the role of GM in triggering and modulating SLE and LN on the one hand, while exploring possible therapeutic manipulation of GM to control the disease on the other hand.

Mental Health Disorders Due to Gut Microbiome Alteration and NLRP3 Inflammasome Activation After Spinal Cord Injury: Molecular Mechanisms, Promising Treatments, and Aids from Artificial Intelligence

Aside from its immediate traumatic effects, spinal cord injury (SCI) presents multiple secondary complications that can be harmful to those who have been affected by SCI. Among these secondary effects, gut dysbiosis (GD) and the activation of the NOD (nucleotide-binding oligomerization domain) like receptor-family pyrin-domain-containing three (NLRP3) inflammasome are of special interest for their roles in impacting mental health. Studies have found that the state of the gut microbiome is thrown into disarray after SCI, providing a chance for GD to occur. Metabolites such as short-chain fatty acids (SCFAs) and a variety of neurotransmitters produced by the gut microbiome are hampered by GD. This disrupts healthy cognitive processes and opens the door for SCI patients to be impacted by mental health disorders. Additionally, some studies have found an increased presence and activation of the NLRP3 inflammasome and its respective parts in SCI patients. Preclinical and clinical studies have shown that NLRP3 inflammasome plays a key role in the maturation of pro-inflammatory cytokines that can initiate and eventually aggravate mental health disorders after SCI. In addition to the mechanisms of GD and the NLRP3 inflammasome in intensifying mental health disorders after SCI, this review article further focuses on three promising treatments: fecal microbiome transplants, phytochemicals, and melatonin. Studies have found these treatments to be effective in combating the pathogenic mechanisms of GD and NLRP3 inflammasome, as well as alleviating the symptoms these complications may have on mental health. Another area of focus of this review article is exploring how artificial intelligence (AI) can be used to support treatments. AI models have already been developed to track changes in the gut microbiome, simulate drug-gut interactions, and design novel anti-NLRP3 inflammasome peptides. While these are promising, further research into the applications of AI for the treatment of mental health disorders in SCI is needed.

The impact of gut microbiome on immune and metabolic homeostasis in type 1 diabetes: Clinical insights for prevention and treatment strategies

Type 1 diabetes (T1D) is a complex disease triggered by a combination of genetic and environmental factors, where abnormal autoimmune responses lead to progressive damage of the pancreatic β cells and severe glucose metabolism disorder. Recent studies have increasingly highlighted the close link between gut microbiota dysbiosis and the development of T1D. This review delves into existing population studies to explore the intricate interactions between the gut microbiota and the immune and metabolic homeostasis in T1D. It summarizes how changes in the structure and function of the gut microbiota are closely associated with the onset and progression of T1D across its natural course and clinical stages. More importantly, based on evidence accumulated from clinical observations and trials, we pioneer the discussion on gut microbiota-based T1D prevention and treatment strategies, this not only enriches our understanding of the complex pathological mechanisms of T1D but also provides potential directions for developing novel prevention and treatment strategies.

Beyond the Hayflick limit: How microbes influence cellular aging

Cellular senescence, a complex biological process resulting in permanent cell-cycle arrest, is central to aging and age-related diseases. A key concept in understanding cellular senescence is the Hayflick Limit, which refers to the limited capacity of normal human cells to divide, after which they become senescent. Senescent cells (SC) accumulate with age, releasing pro-inflammatory and tissue-remodeling factors collectively known as the senescence-associated secretory phenotype (SASP). The causes of senescence are multifaceted, including telomere attrition, oxidative stress, and genotoxic damage, and they extend to influences from microbial sources. Research increasingly emphasizes the role of the microbiome, especially gut microbiota (GM), in modulating host senescence processes. Beneficial microbial metabolites, such as short-chain fatty acids (SCFAs), support host health by maintaining antioxidant defenses and reducing inflammation, potentially mitigating senescence onset. Conversely, pathogenic bacteria like Pseudomonas aeruginosa and Helicobacter pylori introduce factors that damage host DNA or increase ROS, accelerating senescence via pathways such as NF-κB and p53-p21. This review explores the impact of bacterial factors on cellular senescence, highlighting the role of specific bacterial toxins in promoting senescence. Additionally, it discusses how dysbiosis and the loss of beneficial microbial species further contribute to age-related cellular deterioration. Modulating the gut microbiome to delay cellular senescence opens a path toward targeted anti-aging strategies. This work underscores the need for deeper investigation into microbial influence on aging, supporting innovative interventions to manage and potentially reverse cellular senescence.

Role of chemokines in aging and age-related diseases

Chemokines (chemotactic cytokines) play essential roles in developmental process, immune cell trafficking, inflammation, immunity, angiogenesis, cellular homeostasis, aging, neurodegeneration, and tumorigenesis. Chemokines also modulate response to immunotherapy, and consequently influence the therapeutic outcome. The mechanisms underlying these processes are accomplished by interaction of chemokines with their cognate cell surface G protein-coupled receptors (GPCRs) and subsequent cellular signaling pathways. Chemokines play crucial role in influencing aging process and age-related diseases across various tissues and organs, primarily through inflammatory responses (inflammaging), recruitment of macrophages, and orchestrated trafficking of other immune cells. Chemokines are categorized in four distinct groups based on the position and number of the N-terminal cysteine residues; namely, the CC, CXC, CX3C, and (X)C. They mediate inflammatory responses, and thereby considerably impact aging process across multiple organ-systems. Therefore, understanding the underlying mechanisms mediated by chemokines may be of crucial importance in delaying and/or modulating the aging process and preventing age-related diseases. In this review, we highlight recent progress accomplished towards understanding the role of chemokines and their cellular signaling pathways involved in aging and age-relaed diseases of various organs. Moreover, we explore potential therapeutic strategies involving anti-chemokines and chemokine receptor antagonists aimed at reducing aging and mitigating age-related diseases. One of the modern methods in this direction involves use of chemokine receptor antagonists and anti-chemokines, which suppress the pro-inflammatory response, thereby helping in resolution of inflammation. Considering the wide-spectrum of functional involvements of chemokines in aging and associated diseases, several clinical trials are being conducted to develop therapeutic approaches using anti-chemokine and chemokine receptor antagonists to improve life span and promote healthy aging.

The cellular and molecular mechanisms mediating the protective effects of sodium-glucose linked transporter 2 inhibitors against metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease (NAFLD), is a common, highly heterogeneous condition that affects about a quarter of the world's population, with no approved drug therapy. Current evidence from preclinical research and a number of small clinical trials indicates that SGLT2 inhibitors could also be effective for MAFLD. MAFLD is associated with a higher risk of chronic liver disease and multiple extrahepatic events, especially cardiovascular disease (CVD) and chronic kidney disease (CKD). MAFLD is considered a more appropriate terminology than NAFLD because it captures the complex bidirectional interplay between fatty liver and metabolic dysfunctions associated with disease progression, such as obesity and type 2 diabetes mellitus (T2DM). SGLT2 inhibitors are antidiabetic drugs that block glucose reabsorption in the kidney proximal tubule. In this article, we reviewed current clinical evidence supporting the potential use of SGLT2 inhibitors as a drug therapy for MAFLD and discussed the possible cellular and molecular mechanisms involved. We also reviewed the clinical benefits of SGLT2 inhibitors against MAFLD-related comorbidities, especially CVD, CKD and cardiovascular-kidney-metabolic syndrome (CKM). The broad beneficial effects of SGLT2 inhibitors support their use, likely in combination with other drugs, as a therapy for MAFLD.

Epigallocatechin-3-Gallate, Quercetin, and Kaempferol for Treatment of Parkinson's Disease Through Prevention of Gut Dysbiosis and Attenuation of Multiple Molecular Mechanisms of Pathogenesis

Parkinson's disease (PD) is a neurodegenerative condition in which degeneration mostly occurs in the dopamine (DA)-producing neurons within the substantia nigra in the midbrain. As a result, individuals with this condition suffer from progressively worsening motor impairment because of the resulting DA deficiency, along with an array of other symptoms that, over time, force them into a completely debilitating state. As an age-related disease, PD has only risen in prevalence over the years; thus, an emphasis has recently been placed on discovering a new treatment for this condition that is capable of attenuating its progression. The gut microbiota has become an area of intrigue among PD studies, as research into this topic has shown that imbalances in the gut microbiota (colloquially known as gut dysbiosis) seemingly promote the primary etiologic factors that have been found to be associated with PD and its pathologic progression. With this knowledge, research into PD treatment has begun to expand beyond synthetic pharmaceutical compounds, as a growing emphasis has been placed on studying plant-derived polyphenolic compounds, namely flavonoids, as a new potential therapeutic approach. Due to their capacity to promote a state of homeostasis in the gut microbiota and their long-standing history as powerful medicinal agents, flavonoids have begun to be looked at as promising therapeutic agents capable of attenuating several of the pathologic states seen amidst PD through indirect and direct means. This review article focuses on three flavonoids, specifically epigallocatechin-3-gallate, quercetin, and kaempferol, discussing the mechanisms through which these powerful flavonoids can potentially prevent gut dysbiosis, neuroinflammation, and other molecular mechanisms involved in the pathogenesis and progression of PD, while also exploring their real-world application and how issues of bioavailability and potential drug interactions can be circumvented or exploited.

Role of phage therapy in acute gastroenteritis

The gut ecosystem, comprising the gut microbiota and its interactions, plays a crucial role in human health and disease. This complex ecosystem involves a diverse array of microorganisms such as viruses, fungi, and bacteria, collectively known as the gut microbiota. These microorganisms contribute to various functions, including nutrient metabolism and immune modulation, thereby impacting human health. Dysbiosis, or an imbalance in the gut microbiota, has been associated with the pathogenesis of several diseases, ranging from intestinal disorders such as inflammatory bowel disease to extra-intestinal conditions such as metabolic and neurological disorders. The implications of dysbiosis in the gut ecosystem are far-reaching, affecting not only gastrointestinal health but also contributing to the development and progression of conditions such as autoimmune gastritis and gastric cancer. Furthermore, the burden of antimicrobial use and subsequent side effects, including antibiotic resistance, poses additional challenges in managing gastrointestinal diseases. In light of these complexities, investigating the role of bacteriophages as regulators of the gut ecosystem and their potential clinical applications presents a promising opportunity to tackle antibiotic resistance and fight infectious diseases.

Gut microbial dysbiosis and inflammation: Impact on periodontal health

Periodontitis is widely acknowledged as the most prevalent type of oral inflammation, arising from the dynamic interplay between oral pathogens and the host's immune responses. It is also recognized as a contributing factor to various systemic diseases. Dysbiosis of the oral microbiota can significantly alter the composition and diversity of the gut microbiota. Researchers have delved into the links between periodontitis and systemic diseases through the "oral-gut" axis. However, whether the associations between periodontitis and the gut microbiota are simply correlative or driven by causative mechanistic interactions remains uncertain. This review investigates how dysbiosis of the gut microbiota impacts periodontitis, drawing on existing preclinical and clinical data. This study highlights potential mechanisms of this interaction, including alterations in subgingival microbiota, oral mucosal barrier function, neutrophil activity, and abnormal T-cell recycling, and offers new perspectives for managing periodontitis, especially in cases linked to systemic diseases.

Effects of Malted Rice Amazake Consumption on Nutritional Status and Gut Microbiome in Older Patients and Residents of an Integrated Facility for Medical and Long-Term Care

Malnutrition is observed in approximately 20-50% of hospitals and long-term care facilities. We examined the effects of malted rice amazake beverage on the nutritional status and gut microbiome of older patients and residents in an integrated long-term care facility; 13 older patients and residents (84.6 ± 9.3 years) were prescribed 35 g of malted rice amazake daily for six weeks. Gut microbiome analysis, body composition and blood biochemistry test results, defecation surveys, dietary intake, and medications were recorded before and after the intervention. After the intervention, the Geriatric Nutritional Risk Index (GNRI) increased from 83.6 ± 9.1 points to 86.0 ± 9.8 points, and serum albumin increased from 3.3 ± 0.5 g/dL to 3.4 ± 0.5 g/dL. The α-diversity of gut bacteria increased from 390.1 ± 89.4 before to 447.2 ± 108.1, and the abundance of Desulfovibrio decreased from 0.76 ± 0.47% to 0.56 ± 0.60%. ΔGNRI showed a positive correlation with ΔBifidobacterium and ΔBarnesiella, but a negative correlation with ΔKlebsiella. Consumption of malted rice amazake for six weeks improved the GNRI and altered the gut microbiome of older patients and residents at moderate risk of nutritional disorders. Malted rice amazake may be a new way to improve nutrition because it has a high nutritional value, mainly in terms of carbohydrates, and improves the gut microbiome.

Dietary Influences on Gut Microbiota and Their Role in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major contributor to liver-related morbidity, cardiovascular disease, and metabolic complications. Lifestyle interventions, including diet and exercise, are first line in treating MASLD. Dietary approaches such as the low-glycemic-index Mediterranean diet, the ketogenic diet, intermittent fasting, and high fiber diets have demonstrated potential in addressing the metabolic dysfunction underlying this condition. The development and progression of MASLD are closely associated with taxonomic shifts in gut microbial communities, a relationship well-documented in the literature. Given the importance of diet as a primary treatment for MASLD, it is important to understand how gut microbiota and their metabolic byproducts mediate favorable outcomes induced by healthy dietary patterns. Conversely, microbiota changes conferred by unhealthy dietary patterns such as the Western diet may induce dysbiosis and influence steatotic liver disease through promoting hepatic inflammation, up-regulating lipogenesis, dysregulating bile acid metabolism, increasing insulin resistance, and causing oxidative damage in hepatocytes. Although emerging evidence has identified links between diet, microbiota, and development of MASLD, significant gaps remain in understanding specific microbial roles, metabolite pathways, host interactions, and causal relationships. Therefore, this review aims to provide mechanistic insights into the role of microbiota-mediated processes through the analysis of both healthy and unhealthy dietary patterns and their contribution to MASLD pathophysiology. By better elucidating the interplay between dietary nutrients, microbiota-mediated processes, and the onset and progression of steatotic liver disease, this work aims to identify new opportunities for targeted dietary interventions to treat MASLD efficiently.

Correlation of fecal microbiome dysregulation to synovial transcriptome in an equine model of obesity associated osteoarthritis

Background

Osteoarthritis (OA) is increasingly thought to be a multifactorial disease in which sustained gut inflammation serves as a continued source of inflammatory mediators driving degenerative processes at distant sites such as joints. The objective of this study was to use the equine model of naturally occurring obesity associated OA to compare the fecal microbiome in OA and health and correlate those findings to differential gene expression synovial fluid (SF) cells, circulating leukocytes and cytokine levels (plasma, SF) towards improved understanding of the interplay between microbiome and immune transcriptome in OA pathophysiology.

Methods

Feces, peripheral blood mononuclear cells (PBMCs), and SF cells were isolated from healthy skeletally mature horses (n=12; 6 males, 6 females) and those with OA (n=6, 2 females, 4 males). Horses were determined to have OA via lameness evaluation, response to intra-articular (IA) diagnostic analgesia, and radiographic and arthroscopic evidence. Horses were excluded who had received medications or joint injections within 2 months. Cytokine analyses of plasma and SF were performed via multiplex immunoassay. Fecal bacterial microbial 16s DNA sequencing was performed and correlated to bulk RNA sequencing of SF cells and PBMC performed using an Illumina based platform.

Results

Horses with OA had higher body condition scores (P=0.009). Cytokines were elevated in plasma [interleukin (IL)-2, IL-6, IL-18, interferon gamma (IFN-γ), interferon gamma inducible protein 10 (CXCL10 or IP-10), granulocyte colony-stimulating factor (G-CSF)] and SF (IL-1β, IL-6, IL-17A, IL-18, IP-10, G-CSF) in OA. Microbial principal coordinate analysis (PCoA) using Bray-Curtis dissimilarity for β-diversity demonstrated distinct grouping of samples from OA versus healthy horses (P=0.003). Faith alpha diversity was reduced in OA (P=0.02). Analysis of microbiome composition showed differential relative abundance of taxa on multiple levels in OA. Specific phyla (Firmicutes, Verrucomicrobia, Tenericutes, Fibrobacteres), correlated to transcriptomic differences related to cell structure, extracellular matrix, collagen, laminin, migration, and motility, or immune response to inflammation in OA.

Conclusions

These findings provide compelling evidence for a link between obesity, gut microbiome dysbiosis and differential gene expression in distant joint sites associated with development of OA in a relevant large animal model, establishing a connection here that provides a platform from which development of therapeutic interventions targeting the gut microbiome can build.

Omega-3 Fatty Acid and Vitamin D Supplementations Partially Reversed Metabolic Disorders and Restored Gut Microbiota in Obese Wistar Rats

Obesity is a global public health issue linked to various comorbidities in both humans and animals. This study investigated the effects of vitamin D (VD) and omega-3 fatty acids (ω3FA) on obesity, gut dysbiosis, and metabolic alterations in Wistar rats. After 13 weeks on a standard (S) or High-Fat, High-Sugar (HFHS) diet, the rats received VD, ω3FA, a combination (VD/ω3), or a control (C) for another 13 weeks. The HFHS diet led to increased weight gain, abdominal circumference, glucose intolerance, insulin resistance, and gut dysbiosis. VD supplementation improved their fasting blood glucose and reduced liver damage, while ω3FA slowed BMI progression, reduced abdominal fat, liver damage, and intestinal permeability, and modulated the gut microbiota. The combination of VD/ω3 prevented weight gain, decreased abdominal circumference, improved glucose tolerance, and reduced triglycerides. This study demonstrates that VD and ω3FA, alone or combined, offer significant benefits in preventing obesity, gut dysbiosis, and metabolic alterations, with the VD/ω3 combination showing the most promise. Further research is needed to explore the mechanisms behind these effects and their long-term potential in both animal and human obesity management.

Integrated Metagenomic and Metabolomic Analysis of In Vitro Murine Gut Microbial Cultures upon Bisphenol S Exposure

BACKGROUND

The gut microbiota are an important interface between the host and the environment, mediating the host's interactions with nutritive and non-nutritive substances. Dietary contaminants like Bisphenol A (BPA) may disrupt the microbial community, leaving the host susceptible to additional exposures and pathogens. BPA has long been a controversial and well-studied contaminant, so its structural analogues like Bisphenol S (BPS) are replacing it in consumer products, but have not been well studied.

METHODS

This study aimed to determine the impact of BPS on C57BL/6 murine gut microbiota using shotgun metagenomic sequencing and the metabolomic profiling of in vitro anaerobic cultures.

RESULTS

The results demonstrated that a supraphysiologic BPS dose did not overtly distort the metagenomic or metabolomic profiles of exposed cultures compared to controls. A distinct BPS-associated metabolite profile was not observed, but several metabolites, including saturated fatty acids, were enriched in the BPS-exposed cultures. In the absence of a BPS-associated enterotype, Lactobacillus species specifically were associated with BPS exposure in a discriminant model.

CONCLUSIONS

Our study provides evidence contrasting the effects of BPS in the gut microbiome to its predecessor, BPA, but also emphasizes the role of inter-animal variation in microbiome composition, indicating that further study is needed to characterize BPS in this context.

The Impact of Mycobacterium avium subsp. paratuberculosis on Intestinal Microbial Community Composition and Diversity in Small-Tail Han Sheep

Paratuberculosis (PTB), primarily caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic infection that affects ruminants and is difficult to prevent, diagnose, and treat. Investigating how MAP infections affect the gut microbiota in sheep can aid in the prevention and treatment of ovine PTB. This study examined fecal samples from eight small-tail Han sheep (STHS) at various stages of infection and from three different field areas. All samples underwent DNA extraction and 16S rRNA sequencing. Among all samples, the phyla p. Firmicutes and p. Bacteroidota exhibited the highest relative abundance. The dominant genera in groups M1-M6 were UCG-005, Christensenellaceae_R-7_group, Rikenellaceae_RC9_gut_group, Akkermansia, UCG-005, and Bacteroides, whereas those in groups A-C were Christensenellaceae_R-7_group, Escherichia-Shigella, and Acinetobacter, respectively. The microbial community structure varied significantly among groups M1-M6. Specifically, 56 microbiota consortia with different taxonomic levels, including the order Clostridiales, were significantly enriched in groups M1-M6, whereas 96 microbiota consortia at different taxonomic levels, including the family Oscillospiraceae, were significantly enriched in groups A-C. To the best of our knowledge, this is the first study to report that MAP infection alters the intestinal microbiota of STHS. Changes in p. Firmicutes abundance can serve as a potential biomarker to distinguish MAP infection and determine the infection stage for its early diagnosis. Our study provides a theoretical basis for the treatment of PTB by regulating the intestinal microbiota, including p. Firmicutes.

Medicinal Cannabis and the Intestinal Microbiome

Historically, the multiple uses of cannabis as a medicine, food, and for recreational purposes as a psychoactive drug span several centuries. The various components of the plant (i.e., seeds, roots, leaves and flowers) have been utilized to alleviate symptoms of inflammation and pain (e.g., osteoarthritis, rheumatoid arthritis), mood disorders such as anxiety, and intestinal problems such as nausea, vomiting, abdominal pain and diarrhea. It has been established that the intestinal microbiota progresses neurological, endocrine, and immunological network effects through the gut-microbiota-brain axis, serving as a bilateral communication pathway between the central and enteric nervous systems. An expanding body of clinical evidence emphasizes that the endocannabinoid system has a fundamental connection in regulating immune responses. This is exemplified by its pivotal role in intestinal metabolic and immunity equilibrium and intestinal barrier integrity. This neuromodulator system responds to internal and external environmental signals while also serving as a homeostatic effector system, participating in a reciprocal association with the intestinal microbiota. We advance an exogenous cannabinoid-intestinal microbiota-endocannabinoid system axis potentiated by the intestinal microbiome and medicinal cannabinoids supporting the mechanism of action of the endocannabinoid system. An integrative medicine model of patient care is advanced that may provide patients with beneficial health outcomes when prescribed medicinal cannabis.

A Comprehensive Metabolomic and Microbial Analysis Following Dietary Amino Acid Reduction in Mice

Introduction: Nutritional metabolomics provides a comprehensive overview of the biochemical processes that are induced by dietary intake through the measurement of metabolite profiles in biological samples. However, there is a lack of deep phenotypic analysis that shows how dietary interventions influence the metabolic state across multiple physiologic sites. Dietary amino acids have emerged as important nutrients for physiology and pathophysiology given their ability to impact cell metabolism. Methods: The aim of the current study is to evaluate the effect of modulating amino acids in diet on the metabolome and microbiome of mice. Here, we report a comprehensive metabolite profiling across serum, liver, and feces, in addition to gut microbial analyses, following a reduction in either total dietary protein or diet-derived non-essential amino acids in mice. Results: We observed both distinct and overlapping patterns in the metabolic profile changes across the three sample types, with the strongest signals observed in liver and serum. Although amino acids and related molecules were the most commonly and strongly altered group of metabolites, additional small molecule changes included those related to glycolysis and the tricarboxylic acid cycle. Microbial profiling of feces showed significant differences in the abundance of select species across groups of mice. Conclusions: Our results demonstrate how changes in dietary amino acids influence the metabolic profiles across organ systems and the utility of metabolomic profiling for assessing diet-induced alterations in metabolism.

Global research trajectories in gut microbiota and functional constipation: a bibliometric and visualization study

Background

Functional constipation (FC) negatively impacts quality of life and is associated with gut microbiota (GM) imbalances. Despite the growing interest in this area, a thorough analysis of research trends is missing. This study uses bibliometric methods to assess the global research on GM's role in FC, pinpointing key topics, impactful studies, and prominent researchers to guide future research and identify gaps.

Methods

In our study, we conducted a performance analysis and science mapping using bibliometric indicators such as publication trends, author and institutional contributions, productivity, impact, keyword analysis, and collaboration networks. We employed software tools like VOSviewer, Biblioshiny, CiteSpace, and SCImago Graphica to automate the assessment of metrics including country, institutional, and journal distribution, authorship, keyword frequency, and citation patterns.

Results

From 2013 to 2024, annual publications on GM and FC rose from 29 to 252, with a slight decrease to 192 in 2024. Average citations per publication peaked at 11.12 in 2021, declining to 6.43 by 2024. China led in research output (37.8%), followed by the United States (14.4%) and Japan (7.5%). Bibliometric analysis identified key authors like CHEN W and ZHANG H, with 30 and 27 articles, respectively. Jiangnan University and Harvard University were top contributors, with 131 and 81 articles. Keywords analysis revealed "constipation," "gut microbiota," and "probiotic" as central themes, with a shift toward "gut microbiota" and "intestinal flora" in recent years. This study provides a comprehensive overview of the research landscape, highlighting leading authors, institutions, and evolving research priorities in the field.

Conclusion

Our review synthesizes current GM and FC research, guiding future studies. It suggests exploring GM in various GI disorders, the impact of lifestyle and drugs on GM, advanced research techniques, and probiotics/prebiotics for FC. There's also a focus on therapies targeting GM's effect on the gut-brain axis, paving the way for improved FC management.

Modulating effects of heat-killed and live Limosilactobacillus reuteri PSC102 on the immune response and gut microbiota of cyclophosphamide-treated rats

In the present study, we investigated the potential immunomodulatory effects of heat-killed (hLR) and live Limosilactobacillus reuteri PSC102 (LR; formerly Lactobacillus reuteri PSC102) in RAW264.7 macrophage cells and Sprague-Dawley rats. RAW264.7 murine macrophage cells were stimulated with hLR and LR for 24 h. Cyclophosphamide (CTX)-induced immunosuppressed Sprague-Dawley rats were orally administered with three doses of hLR (L-Low, M-Medium, and H-High) and LR for 3 weeks. The phagocytic capacity, production of nitric oxide (NO), and expression of cytokines in RAW264.7 cells were measured, and the different parameters of immunity in rats were determined. hLR and LR treatments promoted phagocytic activity and induced the production of NO and the expression of iNOS, TNF-α, IL-1β, IL-6, and Cox-2 in macrophage cells. In the in vivo experiment, hLR and LR treatments significantly increased the immune organ indices, alleviated the spleen injury, and ameliorated the number of white blood cells, granulocytes, lymphocytes, and mid-range absolute counts in immunosuppressive rats. hLR and LR increased neutrophil migration and phagocytosis, splenocyte proliferation, and T lymphocyte subsets (CD4+, CD8+, CD45RA+, and CD28+). The levels of immune factors (IL-2, IL-4, IL-6, IL-10, IL-12A, TNF-α, and IFN-γ) in the hLR and LR groups were upregulated compared with those in the CTX-treatment group. hLR and LR treatments could also modulate the gut microbiota composition, thereby increasing the relative abundance of Bacteroidetes and Firmicutes but decreasing the level of Proteobacteria. hLR and LR protected against CTX-induced adverse reactions by modulating the immune response and gut microbiota composition. Therefore, they could be used as potential immunomodulatory agents.

Partially hydrolyzed guar gum suppresses binge alcohol-induced liver fat accumulation via gut environment modulation in mice

Alcohol-associated liver disease (ALD), including alcoholic fatty liver, is a serious problem in many countries, and its economic costs to society are enormous. There is evidence indicating the relations between gut environments and liver disease, and thus, improvement of gut environment is expected to be an effective approach for ALD prevention. In this study, we explored the preventive effect of partially hydrolyzed guar gum (PHGG) on ALD focusing on the gut-liver axis. Two weeks of PHGG pre-feeding suppressed the liver fat accumulation in the experimental binge alcohol model mouse. In cecal microbiome, PHGG pre-feeding increased beneficial Bifidobacterium with its metabolite acetate concentration and suppressed the alcohol-induced increase in the potential pathobiont Streptococcus. PHGG pre-feeding increased colonic gene expression of angiogenin genes, which act as antimicrobial peptides and decreased expression of genes for mast cell protease, which suggests a potential involvement in leaky gut. Correlation network analysis based on evaluated parameters revealed four relations worth noticing. (i) The abundance of Bifidobacterium positively correlated with cecal acetate. (ii) Cecal acetate negatively correlated with Streptococcus via colonic angiogenin expression. (iii) Streptococcus positively correlated with liver fat area. (iv) Cecal acetate had direct negative correlation with liver fat area. Considering these relations comprehensively, acetate produced by Bifidobacterium may be a key mediator in ALD prevention; it inhibited growth of potential pathobiont Streptococcus and also directly regulated liver lipid metabolism reaching through portal vein. This study demonstrated that regularly intake of PHGG may be effective in reducing the risk of alcoholic fatty liver via gut-liver axis.

Diabetic neuropathy: understanding the nexus of diabetic neuropathy, gut dysbiosis and cognitive impairment

Objectives

Diabetic neuropathy is a traditional and one of the most prevalent complications of diabetes mellitus. The exact pathophysiology of diabetic neuropathy is not fully understood. However, oxidative stress and inflammation are proven to be one of the major underlying mechanisms of neuropathy which is described in detail. Gut dysbiosis is being studied for various neurological disorders and its impact on diabetic neuropathy is also explained. Diabetic neuropathy also causes loss in an individual's quality of life and one such adverse event is cognitive dysfunction. The interrelation between the neuropathy, cognitive dysfunction and gut is reviewed.

Methods

The exact mechanism is not understood but several hypotheses, cross-sectional studies and systematic reviews suggest a relationship between cognition and neuropathy. The review has collected data from various review and research publications that justifies this inter-relationship.

Results

The multifactorial etiology and pathophysiology of diabetic neuropathy is described with special emphasis on the role of gut dysbiosis. There might exist a correlation between the neuropathy and cognitive impairment caused simultaneously in diabetic patients.

Conclusions

This review summarizes the relationship that might exist between diabetic neuropathy, cognitive dysfunction and the impact of disturbed gut microbiome on its development and progression.

Factors of faecal microbiota transplantation applied to cancer management

The homeostasis of the microbiota is essential for human health. In particular, the gut microbiota plays a critical role in the regulation of the immune system. Thus, faecal microbiota transplantation (FMT), a technology that has rapidly developed in the last decade, has specifically been utilised for the treatment of intestinal inflammation and has recently been found to be able to treat tumours in combination with immunotherapy. FMT has become a breakthrough in enhancing the response rate to immunotherapy in cancer patients by altering the composition of the patient's gut microbiota. This review discusses the mechanisms of faecal microorganism effects on tumour development, drug treatment efficacy, and adverse effects and describes the recent clinical research trials on FMT. Moreover, the factors influencing the efficacy and safety of FMT are described. We summarise the possibilities of faecal transplantation in the treatment of tumours and its complications and propose directions to explore the development of FMT.

Fecal Microbiota Transplantation Activity of Floccularia luteovirens Polysaccharides and Their Protective Effect on Cyclophosphamide-Induced Immunosuppression and Intestinal Injury in Mice

Floccularia luteovirens polysaccharides (FLP1s) have potential biological activities. Our previous study showed that FLP1s positively regulated gut immunity and microbiota. However, it is still unclear whether FLP1s mediate gut microbiota in immunosuppressed mice. This research aims to explore the relationship between FLP1-mediated gut microbes and intestinal immunity in immunosuppressed mice through fecal microbiota transplantation (FMT). The results demonstrated that FLP1s exhibited prebiotic and anti-immunosuppressive effects on CTX-induced immunosuppressed mice. FFLP1 treatment (microbiota transplantation from the fecal sample) remarkably elevated the production of sIgA and secretion of the anti-inflammatory cytokines IL-4, TNF-α, and IFN-γ in the intestine of CTX-treated mice, inducing activation of the MAPK pathway. Moreover, FFLP1s mitigated oxidative stress by activating the Nrf2/Keap1 signaling pathway and strengthened the intestinal barrier function by upregulating the expression level of tight junction proteins (occludin, claudin-1, MUC-2, and ZO-1). Furthermore, FFPL1s restored gut dysbiosis in CTX-treated immunosuppressed mice by increasing the abundance of Alloprevotella, Lachnospiraceae, and Bacteroides. They also modified the composition of fecal metabolites, leading to enhanced regulation of lipolysis in adipocytes, the cGMP-PKG pathway, the Rap1 signaling pathway, and ovarian steroidogenesis, as indicated by KEGG pathway analysis. These findings indicate that FLP1s could modulate the response of the intestinal immune system through regulation of the gut microbiota, thus promoting immune activation in CTX-treated immunosuppressed mice. FLP1s can serve as a natural protective agent against CTX-induced immune injury.