Search Results (907)

Colorectal cancer (CRC) is one of the most common cancers, accounting for approximately 10% of all new cancer cases globally. An increasing number of studies have revealed that the gut microbiome is strongly associated with the pathogenesis and progression of CRC. Based on these advances, this review delineates the mechanistic links between specific microbes and CRC, as well as emerging food-related nutritional intervention strategies. In vivo and in vitro studies have pinpointed the implications of key microbes such as Fusobacterium nucleatum, certain strains of Escherichia coli, enterotoxigenic Bacteroides fragilis, and Enterococcus faecalis, among others, and metabolite involvement and immune responses. Particular attention is paid to the roles of intratumoral microbiota in the development and treatment of CRC, given their direct interaction with tumor cells. Various food-related nutritional intervention strategies have been developed to mitigate CRC risk, including probiotics, antibiotics, or the administration of bioactive compounds such as luteoloside. Finally, we outline critical research directions regarding the influence of animal lineage, carcinoma location, population demographics, the application of advanced in vitro models, and the mediatory roles of gut-associated epithelial cells. In summary, this review might consolidate our current knowledge on the contribution of gut microbiota to CRC and highlights the microbe-based strategies to enhance nutritional interventions for this disease. Full article

Recent studies increasingly highlight the complex interaction between gut microbiota and mental health, drawing attention to the role of the microbiota–gut–brain axis (MGBA) in the pathophysiology of mental and neurodevelopmental disorders. Changes in the composition of the gut microbiota—dysbiosis—are associated with conditions such as depression, schizophrenia, bipolar disorder (BD), autism spectrum disorders (ASD), attention deficit hyperactivity disorder (ADHD), and neurodegenerative diseases such as Parkinson’s and Alzheimer’s. These microbial imbalances can affect brain function through a variety of mechanisms, including activation of the immune system, alteration of intestinal permeability, modulation of the digestive and central nervous systems, and changes in the production of neuroactive metabolites such as short-chain fatty acids, serotonin, and tryptophan derivatives. The aim of this paper is to review the current state of knowledge on therapeutic strategies targeting the gut microbiome—including probiotics, prebiotics, synbiotics, personalized dietary interventions, and fecal microbiota transplantation (FMT)—which are becoming promising adjuncts or alternatives to conventional psychopharmacology, offering a forward-looking and individualized approach to mental health treatment. Understanding the bidirectional and multifactorial nature of MGBA may pave the way for new, integrative treatment paradigms in psychiatry and neurology, requiring further research and exploration of their scope of application. Full article

In humans, the bioactivity of polyphenols is highly dependent on dose intake and their interactions with the gastrointestinal tract and gut microbiota, which metabolize polyphenols into bioactive or inactive derivatives. Polyphenols are only partially absorbed in the small intestine, where enzymatic hydrolysis releases aglycone forms that may cross the gut barrier. A significant proportion of polyphenols escapes absorption and reaches the colon, where resident microbes convert them into simpler phenolic metabolites. Such molecules are often more bioavailable than the parent compounds and can enter systemic circulation, leading to distant effects. Although higher polyphenol consumption has been associated with preventive and therapeutic outcomes, even low intake or poor intestinal absorption may still confer benefits, as polyphenols in the colon can positively modulate gut microbiota composition and function, contributing to favorable shifts in the microbial metabolome. These interactions can influence host metabolic, immune, and neurological pathways, particularly through the gut–liver–brain axis. To provide a comprehensive understanding of these relationships, this review examines the dose-related activity of polyphenols, their microbiota-mediated biotransformation, their bioavailability, and the health effects of their metabolites, while also presenting a comparative overview of key studies in the field. We underscore the importance of integrating microbiome and polyphenol research to recapitulate and contextualize the health benefits of dietary polyphenols. Full article

Background/Objectives: Recent evidence suggests that gut microbiota plays an important role in anxiety and stress-related disorders through interactions along the gut–brain axis. Our aim was to determine the microbiological diversity of intestinal microorganisms in individuals with acute and remission phases of PD when compared to healthy individuals. Another aim was also to analyze the differences in the metabolic pathways occurring in the intestinal microbiota of individuals from the three analyzed groups. Methods: A diagnosis was established using the Mini-International Neuropsychiatric Interview (M.I.N.I). The gut’s microbiota composition was analyzed through bacterial 16S rRNA gene sequencing (V1–V2 regions). The clinical evaluations included a BMI measurement, Short Form-36 Health Survey (SF-36), Hamilton Anxiety Scale (HAM-A), Montgomery–Åsberg Depression Rating Scale (MADRS), Columbia-Suicide Severity Rating Scale (C-SSRS), and State-Trait Anxiety Inventory (STAI). Results: We recruited 62 participants (31 PD and 31 controls). After conducting quality control filtering, data from 54 participants were analyzed (25 PD, 11 acute, 14 remission, and 29 controls). Observed richness was lower in the acute PD (63) group than in the control (74) and remission (66) (p = 0.038) groups, whereas the Shannon and Simpson indices and beta diversity (PERMANOVA) were not significantly different. The Ruminococcus gnavus group was enriched in acute PD; no other deconfounded differences in microbial composition were detected. Predicted functional differences were detected by edgeR only and included the pathways that are related to steroid biosynthesis and innate immune signaling. Conclusions: Distinct gut microbial signatures were associated with PD, implicating both the metabolic and inflammatory pathways in disease pathophysiology. Full article

The breast microbiome remains stable throughout a woman’s life. The breast is not a sterile organ, and its microbiota exhibits a distinct composition compared to other body sites. The breast microbiome is a community characterized by an abundance of Proteobacteria and Firmicutes, which represent the result of host microbial adaptation to the fatty acid environment in the tissue. The breast microbiome demonstrates dynamic adaptability during lactation, responding to maternal physiological changes and infant interactions. This microbial plasticity modulates local immune responses, maintains epithelial integrity, and supports tissue homeostasis, thereby influencing both breast health and milk composition. Disruptions in this balance, the dysbiosis, are closely linked to inflammatory breast conditions such as mastitis. Risk factors for breast cancer (BC) include genetic mutations, late menopause, obesity, estrogen metabolism, and alterations in gut microbial diversity. Gut microbiota can increase estrogen bioavailability by deconjugating estrogen-glucuronide moieties. Perturbations of this set of bacterial genes and metabolites, called the estrobolome, increases circulating estrogens and the risk of BC. Fusobacterium nucleatum has recently been associated with BC. It moves from the oral cavity to other body sites hematogenously. This review deals with the characteristics of the breast microbiome, with a focus on F. nucleatum, highlighting its dual role in promoting tumor growth and modulating immune responses. F. nucleatum acts both on the Wnt/β-catenin pathway by positively regulating MYC expression and on apoptosis by inhibiting caspase 8. Furthermore, F. nucleatum binds to TIGIT and CEACAM1, inhibiting T-cell cytotoxic activity and protecting tumor cells from immune cell attack. F. nucleatum also inhibits T-cell function through the recruitment of myeloid suppressor cells (MDSCs). These cells express PD-L1, which further reduces T-cell activation. A deeper understanding of F. nucleatum biology and its interactions with host cells and co-existing symbiotic microbiota could aid in the development of personalized anticancer therapy. Full article

Breast cancer remains a formidable global health challenge, with triple-negative breast cancer (TNBC) posing unique clinical complexities. Characterized by its aggressive nature and limited number of specific therapeutic targets, this breast cancer subtype disproportionately affects African American women, highlighting critical disparities in care. The tumor immune microenvironment (TIME) plays a critical role in breast cancer development and response to immunotherapy, and it is essential in fostering an immunosuppressive and pro-inflammatory niche. Inflammation, primarily mediated by the NF-κB signaling pathway and chemokine signaling, particularly involving CCL2, plays a pivotal role in TNBC progression and therapy resistance. This review describes some of the molecular mechanisms of polyphenols, which are naturally occurring compounds abundant in various dietary sources, and their potential use as therapeutic agents in the management of TNBC. Polyphenolic compounds have been described as modulating the TIME through the inhibition of tumor progression, immune evasion, and therapy resistance, due to their diverse bioactivities, including anti-inflammatory, antioxidant, and anticancer properties, making them attractive candidates for combating the aggressiveness of TNBC and addressing treatment disparities. Polyphenols, such as curcumin, gossypol, butein, epigallocatechin gallate, cardamonin, and resveratrol, have demonstrated efficacy in modulating several signaling pathways within the TIME, which are implicated in the progression of TNBC. This review highlights the potential effects of polyphenols on inflammatory cytokine release, programmed cell death ligand 1 (PD-L1) expression, which is associated with immune evasion by the host cell, and various intracellular signaling cascades, demonstrating their potential use in personalized therapeutic interventions for TNBC. This study also describes differential responses of TNBC cell lines to polyphenol treatment, highlighting the importance of considering genetic variability in therapeutic strategies, as well as the importance of the interaction of polyphenols with the gut microbiome, which may establish the bioavailability and effectiveness of these compounds toward therapeutic outcomes. Further preclinical and clinical studies are warranted to fully elucidate the therapeutic potential of polyphenols and translate these findings into clinical practice, thereby improving outcomes for patients with TNBC worldwide. Full article

The ocular surface microbiome consists of microorganisms that play an important role in maintaining homeostasis and preventing disease from invading pathogens. Commensal microbes on the ocular surface interact with cells and molecules of the ocular surface immune system to promote immune tolerance to the normal flora of the ocular surface and facilitate immune protection against invading pathogenic microbes, which allows for a disease-free ocular surface. Various factors can impact the composition, distribution, and diversity of the ocular surface microbiome, including age, gender, disease state, antibiotic treatment, and contact lens use. In addition, there is no cohesive consensus on the species that make up the ocular surface microbes. There is, however, thorough research present on other similar mucosal membranes, such as the gut and oral mucosa, that share similarities with the ocular mucosa. Exploring the relationship of different mucosae allows us to explore treatment options for common ocular diseases such as dry eye syndrome. This review highlights studies that define the ocular surface microbiome, its diversity and composition, host–immune interactions at the ocular surface, factors that cause dysbiosis of the ocular surface microbiome, the impact of dysbiosis on the ocular surface microbiome, and microbiome-based therapy. Full article

Food-derived carbon dots (F-CDs) are a novel class of carbon-based nanomaterials unintentionally generated during common thermal food processing techniques, such as baking, roasting, frying, and caramelization. These nanostructures exhibit unique optical and chemical properties, including photoluminescence, high aqueous solubility, and tunable surface functionality, making them increasingly relevant to both food science and biomedical research. Recent studies have highlighted their ability to interact with biological systems, particularly the gut microbiota, a critical determinant of host metabolism, immunity, and overall health. This review critically summarizes the current understanding of F-CDs, including their mechanisms of formation, analytical detection methods, and physicochemical properties. It explores their biological fate in the gastrointestinal tract, encompassing absorption, distribution, metabolism, and excretion, with a focus on their stability and cellular uptake. Special attention is given to the interaction between F-CDs and the gut microbiota, where evidence suggests both beneficial (e.g., anti-inflammatory, antioxidant) and detrimental (e.g., dysbiosis, inflammatory signaling) effects, depending on the CD type, dose, and exposure context. Additionally, this review addresses toxicological concerns, highlighting gaps in long-term safety data, standardized detection methods, and regulatory oversight. The dual role of F-CDs—as potential modulators of the microbiota and as emerging dietary nanomaterials with uncharted risks—underscores the need for further interdisciplinary research. Future efforts should aim to refine detection protocols, assess chronic exposure outcomes, and clarify structure–function relationships to enable the safe and responsible application of these nanomaterials in food and health contexts. Full article

Research on the effects of polyunsaturated fatty acids on children’s sleep has made significant advancements. This study explores the unique pathways through which polyunsaturated fatty acids, particularly docosahexaenoic acid and eicosapentaenoic acid from the n-3 series, influence sleep regulation in children. Neurobiologically, docosahexaenoic acid and eicosapentaenoic acid have been shown to bi-directionally modulate neurotransmitters and circadian rhythms via the gut–brain axis, reshaping gut microbiota and affecting brain signaling. In terms of inflammation and immune regulation, this study is the first to confirm that Maresin1, produced from n-3 fatty acids, can inhibit the activation of specific inflammasomes, thereby mitigating the disruptive effects of pro-inflammatory cytokines on sleep. The analysis of clinical applications indicates that newly developed medium- and long-chain triglyceride formulations rich in docosahexaenoic acid exhibit excellent digestive absorption in infants’ gastrointestinal systems, paving the way for new products designed to enhance infant sleep. However, current research has limitations concerning the precise dosing of docosahexaenoic acid, the representativeness of samples, and the overall rigor of study designs. Mechanistically, polyunsaturated fatty acids may exert their effects through various pathways, including neurobiology, inflammation, immune regulation, and endocrine modulation. In clinical studies, different formulations of fish oil show varying safety profiles and bioavailability. Future research should prioritize high-quality studies to clarify how different doses of polyunsaturated fatty acids affect children’s sleep, assess long-term safety, and investigate interactions with other factors, ultimately providing solid theoretical and practical guidance for improving children’s sleep. Full article

The gut microbiota plays a pivotal role in developing colorectal cancer (CRC) through interactions with host immunity, metabolism, and inflammation. However, microbiome-based studies remain scarce in Middle Eastern populations, limiting regional insights into microbial signatures associated with CRC. This study aimed to characterize the gut microbiota profiles of Jordanian CRC patients using 16S rRNA gene sequencing and compare them to those of healthy controls from the GutFeeling KnowledgeBase (GutFeelingKB). Stool samples from 50 CRC patients were analyzed using Illumina iSeq targeting the V3–V4 region. Taxonomic profiling was conducted with a standardized 16S metagenomics pipeline and compared with GutFeelingKB reference data. CRC samples were enriched in Streptococcus, Enterococcus, Klebsiella, Escherichia, Citrobacter, Veillonella, Megamonas, and Eggerthella, while beneficial butyrate-producing genera such as Roseburia, Ruminococcus, Akkermansia, Faecalibacterium, and Bacteroides were significantly depleted. The absence of Fusobacterium nucleatum and Bacteroides fragilis—commonly seen in global studies—suggests region-specific microbial patterns. This study is the first metagenomic study profiling CRC-associated microbiota in Jordan. The findings reveal a dysbiotic microbial signature that reflects both global changes associated with CRC and local ecological influences. This research emphasizes the importance of population-specific microbiome studies and highlights the need to include appropriately matched controls in future investigations. Full article

Alzheimer’s disease (AD), a prevalent neurodegenerative disorder in the aging population, remains without definitive therapeutic solutions. Emerging insights into the gut microbiota (GM) and its bidirectional communication with the central nervous system(CNS) through the microbiota–gut–brain axis (MGBA) have unveiled potential correlative mechanisms that may contribute to AD pathogenesis, though causal evidence remains limited. Dysregulation of GM composition (dysbiosis) exacerbates AD progression via neuroinflammation, amyloid-β (Aβ) deposition, and tau hyperphosphorylation (p-tau), while restoring microbial homeostasis presents a promising therapeutic strategy. Fecal microbiota transplantation (FMT), a technique to reconstitute gut ecology by transferring processed fecal matter from healthy donors, has demonstrated efficacy in ameliorating cognitive deficits and neuropathology in AD animal models. Preclinical studies reveal that FMT reduces Aβ plaques, normalizes tau phosphorylation, suppresses inflammasome activation, and restores microglial homeostasis through modulation of microbial metabolites and immune pathways. Although clinical evidence remains limited to case reports and small-scale trials showing potential therapeutic effect, safety concerns regarding long-term effects and protocol standardization necessitate further investigation. This review synthesizes current knowledge on GM–AD interactions, evaluates FMT’s mechanistic potential, and discusses challenges in translating this ancient practice into a cutting-edge AD therapy. Rigorous randomized controlled trials and personalized microbiota-based interventions are imperative to advance FMT from bench to bedside. Full article

Type 2 diabetes (T2D) is a complex metabolic disease characterized by chronic hyperglycemia due to insulin resistance and inadequate insulin secretion. Beyond the classically implicated organs, emerging evidence highlights the gut as a central player in T2D pathophysiology through its interactions with metabolic organs. The gut hosts trillions of microbes and enteroendocrine cells that influence inflammation, energy homeostasis, and hormone regulation. Disruptions in gut homeostasis (dysbiosis and increased permeability) have been linked to obesity, insulin resistance, and β-cell dysfunction, suggesting multifaceted “Gut-X axes” contribute to T2D development. We aimed to comprehensively review the evidence for gut-mediated crosstalk with the pancreas, endocrine system, liver, and kidneys in T2D. Key molecular mechanisms (incretins, bile acids, short-chain fatty acids, endotoxins, etc.) were examined to construct an integrated model of how gut-derived signals modulate metabolic and inflammatory pathways across organs. We also discuss clinical implications of targeting Gut-X axes and identify knowledge gaps and future research directions. A literature search (2015–2025) was conducted in PubMed, Scopus, and Web of Science, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews). Over 150 high-impact publications (original research and review articles from Nature, Cell, Gut, Diabetologia, Lancet Diabetes & Endocrinology, etc.) were screened. Data on gut microbiota, enteroendocrine hormones, inflammatory mediators, and organ-specific outcomes in T2D were extracted. The GRADE framework was used informally to prioritize high-quality evidence (e.g., human trials and meta-analyses) in formulating conclusions. T2D involves perturbations in multiple Gut-X axes. This review first outlines gut homeostasis and T2D pathogenesis, then dissects each axis: (1) Gut–Pancreas Axis: how incretin hormones (GLP-1 and GIP) and microbial metabolites affect insulin/glucagon secretion and β-cell health; (2) Gut–Endocrine Axis: enteroendocrine signals (e.g., PYY and ghrelin) and neural pathways that link the gut with appetite regulation, adipose tissue, and systemic metabolism; (3) Gut–Liver Axis: the role of microbiota-modified bile acids (FXR/TGR5 pathways) and bacterial endotoxins in non-alcoholic fatty liver disease (NAFLD) and hepatic insulin resistance; (4) Gut–Kidney Axis: how gut-derived toxins and nutrient handling intersect with diabetic kidney disease and how incretin-based and SGLT2 inhibitor therapies leverage gut–kidney communication. Shared mechanisms (microbial SCFAs improving insulin sensitivity, LPS driving inflammation via TLR4, and aryl hydrocarbon receptor ligands modulating immunity) are synthesized into a unified model. An integrated understanding of Gut-X axes reveals new opportunities for treating and preventing T2D. Modulating the gut microbiome and its metabolites (through diet, pharmaceuticals, or microbiota therapies) can improve glycemic control and ameliorate complications by simultaneously influencing pancreatic islet function, hepatic metabolism, and systemic inflammation. However, translating these insights into clinical practice requires addressing gaps with robust human studies. This review provides a state-of-the-art synthesis for researchers and clinicians, underlining the gut as a nexus for multi-organ metabolic regulation in T2D and a fertile target for next-generation therapies. Full article

The gut microbiota is recognized as one of the extrinsic factors that modulate the clinical outcomes of immune checkpoint inhibitors (ICIs), such as inhibitors targeting programmed cell death protein 1 (PD-1), in cancer patients. However, the link between intestinal barrier, which mutually interacts with the gut microbiota, and therapeutic effects has not been extensively studied so far. Therefore, the primary goal of this study was to investigate the relationship between intestinal barrier functionality and clinical outcomes of anti-PD-1 therapy in patients with advanced melanoma. Fecal samples were collected from 64 patients before and during anti-PD-1 therapy. The levels of zonulin, calprotectin, and secretory immunoglobulin A (SIgA), which reflect intestinal permeability, inflammation, and immunity, respectively, were measured in fecal samples (n = 115) using an Enzyme-Linked Immunosorbent Assay (ELISA). Moreover, the composition of the immunoglobulin (Ig)-bound (n = 108) and total stool microbiota (n = 117) was determined by the V3–V4 region of 16S rRNA gene sequencing. ELISA indicated a higher baseline concentration of fecal SIgA in patients with favorable clinical outcomes than those with unfavorable ones. Moreover, high baseline concentrations of intestinal barrier state biomarkers correlated with survival outcomes. In the cases of fecal zonulin and fecal SIgA, there was a positive correlation, while in the case of fecal calprotectin, there was a negative correlation. Furthermore, there were differences in the microbial profiles of the Ig-bound stool microbiota between patients with favorable and unfavorable clinical outcomes and their changes during treatment. Collectively, these findings indicate an association between intestinal barrier functionality and clinical outcomes of anti-PD-1 therapy in advanced melanoma patients. Full article

Background/Aims: Inflammatory bowel diseases (IBDs), including Crohn’s disease (CD) and ulcerative colitis (UC), are chronic conditions marked by dysregulated inflammation in the gastrointestinal tract. Although the pathophysiology of IBD remains incompletely understood, it involves complex interactions between genetic predisposition and environmental triggers, such as gut microbiota imbalances and immune dysfunction, leading to chronic inflammation and mucosal injury. IBD affects approximately 7 million individuals globally, with prevalence increasing in Europe, North America, and Oceania. This rise parallels the growing consumption of ultra-processed foods (UPFs), which are typically rich in sugars, fats, and additives but low in fiber, vitamins, and other essential nutrients. These associations, this review critically examines the influence of UPF consumption on gut microbiota composition and function and its potential link to IBD. Methods: A bibliographic search was conducted in the SciELO, PubMed, and Cochrane databases. Results and Conclusions: High UPF consumption is associated with intestinal dysbiosis, marked by reduced microbial diversity, decreased short-chain fatty acid production, impaired barrier integrity, and mucus layer disruption. These alterations may promote immune-mediated diseases, including IBD, where dysbiosis is often characterized by an overgrowth of pathogenic bacteria such as Clostridium and Enterococcus, ultimately triggering inflammatory responses in the host. Full article

Emerging evidence suggests a critical role of the gut microbiome in modulating systemic immune responses, with increasing relevance in dermatological diseases. Chronic spontaneous urticaria (CSU), traditionally viewed as an isolated cutaneous disorder, is now recognized as a systemic immune condition involving complex interactions between innate and adaptive immunity, mast cell dysregulation, and non-IgE-mediated pathways. This review explores the gut–skin axis as a unifying concept linking intestinal dysbiosis to inflammatory skin diseases, including atopic dermatitis, psoriasis, rosacea, and acne. Special emphasis is placed on CSU, where altered gut microbial composition, characterized by reduced diversity, depletion of short-chain fatty acid-producing bacteria, and expansion of Proteobacteria, may contribute to increased intestinal permeability, systemic immune activation via toll-like receptors, and heightened mast cell sensitivity. We discuss findings from animal models demonstrating that gut microbiota modulation can attenuate mast cell hyperreactivity and reduce urticarial symptoms. In parallel, we examine clinical evidence supporting the potential role of probiotics, prebiotics, dietary interventions, and fecal microbiota transplantation as adjunctive strategies in CSU management. Despite promising findings, challenges remain in translating microbiome research into effective therapies due to interindividual variability, the complexity of host–microbiome interactions, and a lack of standardized protocols. Future research should focus on identifying predictive microbial patterns and developing personalized microbiome-targeted interventions. Understanding the bidirectional gut–skin relationship may open new therapeutic avenues beyond symptomatic treatment, positioning the microbiome as a novel target in CSU and related inflammatory dermatoses. Full article