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The human central nervous system is convolutedly connected to the gut microbiome, a diverse community of microorganisms residing in the gastrointestinal tract. Recent research has highlighted the bidirectional communication between the gut microbiome and neuroglial cells, which include astrocytes, microglia, oligodendrocytes, and ependymal cells. These neuroglial cells are essential for maintaining CNS homeostasis, supporting neuronal function, and responding to pathological conditions. This review examines the interactions between the gut microbiome and neuroglia, emphasizing their critical roles in brain health and the development of neurological disorders. Dysbiosis, or imbalance in the gut microbiome, has been associated with various neurological and psychiatric conditions, such as autism spectrum disorder, anxiety, depression, and neurodegenerative diseases like Alzheimer's and Parkinson's. The microbiome influences brain function through microbial metabolites, immune modulation, and neuroinflammatory responses. Understanding these interactions paves the way for new therapeutic targets and strategies for preventing and treating CNS disorders. This scoping review aims to highlight the mechanisms of the microbiome-neuroglia axis in maintaining brain health and its potential as a therapeutic target. [ABSTRACT FROM AUTHOR]

The human gastrointestinal tract hosts a complex and dynamic community of microorganisms known as the gut microbiota, which play a pivotal role in numerous physiological processes, including digestion, metabolism, and immune function. Recent research has highlighted the significant impact of diet on the gut microbiota composition and functionality, and the consequential effects on host health. Concurrently, there is growing evidence linking the gut microbiota to inflammation, a key factor in many chronic diseases such as inflammatory bowel disease (IBD), obesity, diabetes, and cardiovascular diseases (CVDs). This review explores how dietary components influence the gut microbiota composition, how these microbial changes affect inflammatory pathways, and the therapeutic implications of modulating this axis for chronic inflammatory disease prevention and management. Beneficial dietary patterns, such as the Mediterranean diet (MD) and plant-based diets, promote a diverse and balanced gut microbiota composition, supporting anti-inflammatory pathways. Conversely, the Western diet (WD), high in saturated fats and refined sugars, is associated with dysbiosis and increased inflammation. With all the links between the three variables considered, this review attempts to offer a thorough examination of the triangle formed by inflammation, the gut microbiota, and food. [ABSTRACT FROM AUTHOR]

Background: Inflammatory Bowel Diseases (IBD) are a major public health issue with unclear aetiology. Changes in the composition and functionality of the intestinal microbiota are associated with these pathologies, including the depletion of strict anaerobes such as Feacalibacterium prausnitzii. Less evidence is observed for depletion in other anaerobes, among which bifidobacteria. This study characterized the taxonomic and functional diversity of bifidobacteria isolated from the human intestinal microbiota in active and non-active IBD patients by a culturomics approach and evaluated if these bifidobacteria might be used as probiotics for gut health. Results: A total of 341 bifidobacteria were isolated from the intestinal microbiota of IBD patients (52 Crohn's disease and 26 ulcerative colitis patients), with a high proportion of Bifidobacterium dentium strains (28% of isolated bifidobacteria). In ulcerative colitis, the major species identified was B. dentium (39% of isolated bifidobacteria), in active and non-active ulcerative colitis. In Crohn's disease, B. adolescentis was the major species isolated from non-active patients (40%), while similar amounts of B. dentium and B. adolescentis were found in active Crohn's disease patients. The relative abundance of B. dentium was increased with age, both in Crohn's disease and ulcerative colitis and active and non-active IBD patients. Antibacterial capacities of bifidobacteria isolated from non-active ulcerative colitis against Escherichia coli LF82 and Salmonella enterica ATCC 14028 were observed more often compared to strains isolated from active ulcerative colitis. Finally, B. longum were retained as strains with the highest probiotic potential as they were the major strains presenting exopolysaccharide synthesis, antibacterial activity, and anti-inflammatory capacities. Antimicrobial activity and EPS synthesis were further correlated to the presence of antimicrobial and EPS gene clusters by in silico analysis. Conclusions: Different bifidobacterial taxonomic profiles were identified in the microbiota of IBD patients. The most abundant species were B. dentium, mainly associated to the microbiota of ulcerative colitis patients and B. adolescentis, in the intestinal microbiota of Crohn's disease patients. Additionally, the relative abundance of B. dentium significantly increased with age. Furthermore, this study evidenced that bifidobacteria with probiotic potential (antipathogenic activity, exopolysaccharide production and anti-inflammatory activity), especially B. longum strains, can be isolated from the intestinal microbiota of both active and non-active Crohn's disease and ulcerative colitis patients. [ABSTRACT FROM AUTHOR]

Human milk contains a variety of microorganisms that exert benefit for human health. In the current study, we isolated a novel Lactobacillus gasseri strain named Lactobacillus gasseri (L. gasseri) SHMB 0001 from human milk and aimed to evaluate the probiotic characteristics and protective effects on murine colitis of the strain. The results showed that L. gasseri SHMB 0001 possessed promising potential probiotic characteristics, including good tolerance against artificial gastric and intestinal fluids, adhesion to Caco‐2 cells, susceptibility to antibiotic, no hemolytic activity, and without signs of toxicity or infection in mice. Administration of L. gasseri SHMB 0001 (1 × 108 CFU per gram of mouse weight per day) reduced weight loss, the disease activity index, and colon shortening in mice during murine colitis conditions. Histopathological analysis revealed that L. gasseri SHMB 0001 treatment attenuated epithelial damage and inflammatory infiltration in the colon. L. gasseri SHMB 0001 treatment increased the expression of colonic occludin and claudin‐1 while decreasing the expression of pro‐inflammatory cytokine genes. L. gasseri SHMB 0001 modified the composition and structure of the gut microbiota community and partially recovered the Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways altered by dextran sulfate sodium (DSS). Overall, our results indicated that the human breast milk–derived L. gasseri SHMB 0001 exhibited promising probiotic properties and ameliorative effect on DSS‐induced colitis in mice. L. gasseri SHMB 0001 may be applied as a promising probiotic against intestinal inflammation in the future. Practical Application: L. gasseri SHMB 0001 isolated from human breast milk showed good tolerance to gastrointestinal environment, safety, and protective effect against DSS‐induced mice colitis via enforcing gut barrier, downregulating pro‐inflammatory cytokines, and modulating gut microbiota. L. gasseri SHMB 0001 may be a promising probiotic candidate for the treatment of intestinal inflammation. [ABSTRACT FROM AUTHOR]

The complex role of the gut microbiome in the pathogenesis of gastrointestinal (GI) disorders is an emerging area of research, and there is considerable interest in understanding how diet can alter the composition and function of the microbiome. Prebiotics and probiotics have been shown to beneficially modulate the gut microbiome, which underlies their potential for benefit in GI conditions. Formulating specific recommendations for the public regarding these dietary supplements has been difficult due to the significant heterogeneity between strains, doses, and duration of treatment investigated across studies, as well as safety concerns with administering live organisms. This review aims to summarize the existing evidence for the use of prebiotics and probiotics in various GI disorders, paying special attention to strain-specific effects that emerged and any adverse effects noted. [ABSTRACT FROM AUTHOR]

Vine-growing for the production of wine is one of the oldest and most important agricultural activities worldwide, but the winemaking process leads to vast amounts of waste. Viticulture and vinification by-products have many bioactive molecules, including polyphenols, prebiotic fibers, organic acids, and minerals. While research on the specific human health effects of grapevine residues (pomace, seeds, barks, stalks, canes, and leaves) is still ongoing, the available data suggest the potential to positively modulate the normal and dysbiotic gut microbiota (GM) using polyphenol-rich extracts obtained from winery by-products. This review provides an updated summary of the in vitro and in vivo evidence in animal models and humans concerning the ability of polyphenol-rich winery residue to be used as a GM modulator that supports their nutraceutical applications as a functional ingredient. Additionally, this review aims to enhance interest in viticulture waste (grapevine stems and leaves), as the levels of polyphenols are similar to those found in red grapes or seeds. However, more research is still needed to obtain innovative products. The valorization of winery residues is not only environmentally friendly; it can also be economically beneficial, creating added-value nutraceuticals that modulate microbiota and a new revenue stream for wine producers. [ABSTRACT FROM AUTHOR]

Probiotics, like lactic acid bacteria, are non-pathogenic microbes that exert health benefits to the host when administered in adequate quantity. Currently, research is being conducted on the molecular events and applications of probiotics. The suggested mechanisms by which probiotics exert their action include; competitive exclusion of pathogens for adhesion sites, improvement of the intestinal mucosal barrier, gut immunomodulation, and neurotransmitter synthesis. This review emphasizes the recent advances in the health benefits of probiotics and the emerging applications of probiotics in the food industry. Due to their capability to modulate gut microbiota and attenuate the immune system, probiotics could be used as an adjuvant in hypertension, hypercholesterolemia, cancer, and gastrointestinal diseases. Considering the functional properties, probiotics are being used in the dairy, beverage, and baking industries. After developing the latest techniques by researchers, probiotics can now survive within harsh processing conditions and withstand GI stresses quite effectively. Thus, the potential of probiotics can efficiently be utilized on a commercial scale in food processing industries. [ABSTRACT FROM AUTHOR]

Objective: The gastrointestinal microbiome in preterm infants exhibits significant influence on optimal outcomes–with dysbiosis shown to substantially increase the risk of the life-threatening necrotizing enterocolitis. Iron is a vital nutrient especially during the perinatal window of rapid hemoglobin production, tissue growth, and foundational neurodevelopment. However, excess colonic iron exhibits potent oxidation capacity and alters the gut microbiome–potentially facilitating the proliferation of pathological bacterial strains. Breastfed preterm infants routinely receive iron supplementation starting 14 days after delivery and are highly vulnerable to morbidities associated with gastrointestinal dysbiosis. Therefore, we set out to determine if routine iron supplementation alters the preterm gut microbiome. Methods: After IRB approval, we collected stool specimens from 14 infants born <34 weeks gestation in the first, second, and fourth week of life to assess gut microbiome composition via 16S rRNA sequencing. Results: We observed no significant differences in either phyla or key genera relative abundance between pre- and post-iron timepoints. We observed notable shifts in infant microbiome composition based on season of delivery. Conclusion: Though no obvious indication of iron-induced dysbiosis was observed in this unique study in the setting of prematurity, further investigation in a larger sample is warranted to fully understand iron's impact on the gastrointestinal milieu. [ABSTRACT FROM AUTHOR]

Inflammatory bowel diseases (IBD) like Crohn's and ulcerative colitis (UC) are multifactorial pathologies caused by environmental factors and genetic background. UC is a chronic inflammatory disorder that specifically targets the colon, resulting in inflammation. Various chemical interventions, including aminosalicylates, corticosteroids, immunomodulators, and biological therapies, have been extensively employed for the purpose of managing symptoms associated with UC. Nevertheless, it is important to note that these therapeutic interventions may give rise to undesirable consequences, including, but not limited to, the potential for weight gain, fluid retention, and heightened vulnerability to infections. Emerging therapeutic approaches for UC are costly due to their chronic nature. Alternatives like synbiotic therapy, combining prebiotics and probiotics, have gained attention for mitigating dysbiosis in UC patients. Prebiotics promote beneficial bacteria proliferation, while probiotics establish a balanced gut microbiota and regulate immune system functionality. The utilisation of synbiotics has been shown to improve the inflammatory response and promote the resolution of symptoms in individuals with UC through the stimulation of beneficial bacteria growth and the enhancement of intestinal barrier integrity. Hence, this review article aims to explore the potential benefits and underlying reasons for incorporating alternative approaches in the management of UC with studies performed using prebiotics, probiotics, and synbiotics to treat ulcerative colitis and to highlight safety and considerations in UC and future perspectives. This will facilitate the utilisation of novel treatment strategies for the safer and more efficacious management of patients with UC. [ABSTRACT FROM AUTHOR]

Background: Gut dysbiosis contributes to the high risk of bloodstream infection (BSI) among premature infants. Most prior studies of the premature infant gut microbiota were conducted in Western countries and prior to development of current tools for strain-resolved analysis. Methods: We performed metagenomic sequencing of weekly fecal samples from 75 premature infants at a single hospital in Singapore. We evaluated associations between clinical factors and gut microbiota composition using PERMANOVA and mixed effects linear regression. We used inStrain to perform strain-level analyses evaluating for gut colonization by BSI-causing strains. Results: Median (interquartile range) gestation was 27 (25, 29) weeks, and 63% of infants were born via Cesarean section. Antibiotic exposures (PERMANOVA; R2 = 0.017, p = 0.001) and postnatal age (R2 = 0.015, p = 0.001) accounted for the largest amount of variability in gut microbiota composition. Increasing postnatal age was associated with higher relative abundances of several common pathogens (Enterococcus faecalis: p < 0.0001; Escherichia coli: p < 0.0001; Klebsiella aerogenes: p < 0.0001; Klebsiella pneumoniae: p < 0.0001). Antibiotic exposures were generally associated with lower relative abundances of both frequently beneficial bacteria (e.g., Bifidobacterium species) and common enteric pathogens (e.g., Enterobacter, Klebsiella species). We identified strains identical to the blood culture isolate in fecal samples from 12 of 16 (75%) infants who developed BSI, including all infections caused by typical enteric bacteria. Conclusions: Antibiotic exposures were the dominant modifiable factor affecting gut microbiota composition in a large cohort of premature infants from South-East Asia. Strain-resolved analyses indicate that the gut is an important reservoir for organisms causing BSI among premature infants. [ABSTRACT FROM AUTHOR]

Probiotics, like lactic acid bacteria, are non-pathogenic microbes that exert health benefits to the host when administered in adequate quantity. Currently, research is being conducted on the molecular events and applications of probiotics. The suggested mechanisms by which probiotics exert their action include; competitive exclusion of pathogens for adhesion sites, improvement of the intestinal mucosal barrier, gut immunomodulation, and neurotransmitter synthesis. This review emphasizes the recent advances in the health benefits of probiotics and the emerging applications of probiotics in the food industry. Due to their capability to modulate gut microbiota and attenuate the immune system, probiotics could be used as an adjuvant in hypertension, hypercholesterolemia, cancer, and gastrointestinal diseases. Considering the functional properties, probiotics are being used in the dairy, beverage, and baking industries. After developing the latest techniques by researchers, probiotics can now survive within harsh processing conditions and withstand GI stresses quite effectively. Thus, the potential of probiotics can efficiently be utilized on a commercial scale in food processing industries. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) has become a worldwide public health problem, and the prevalence of the disease among children has been increasing. The pathogenesis of UC has not been elucidated, but dysbiosis of the gut microbiota is considered the main cause of chronic intestinal inflammation. This review focuses on the therapeutic effects of probiotics on UC and the potential mechanisms involved. In animal studies, probiotics have been shown to alleviate symptoms of UC, including weight loss, diarrhea, blood in the stool, and a shortened colon length, while also restoring intestinal microecological homeostasis, improving gut barrier function, modulating the intestinal immune response, and attenuating intestinal inflammation, thereby providing theoretical support for the development of probiotic-based microbial products as an adjunctive therapy for UC. However, the efficacy of probiotics is influenced by factors such as the bacterial strain, dose, and form. Hence, the mechanisms of action need to be investigated further. Relevant clinical trials are currently lacking, so the extension of animal experimental findings to clinical application requires a longer period of consideration for validation. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is the most common type of leukemia in children, comprising 75–85% of cases. Aggressive treatment of leukemias includes chemotherapy and antibiotics that often disrupt the host microbiota. Additionally, the gut microbiota may play a role in the development and progression of acute leukemia. Prebiotics, probiotics, and postbiotics are considered beneficial to health. The role of prebiotics in the treatment and development of leukemia is not well understood, but inulin can be potentially used in the treatment of leukemia. Some probiotic bacteria such as Lactobacillus shows anticancer activity in in vitro studies. Additionally, Bifidobacterium spp., as a consequence of the inhibition of growth factor signaling and mitochondrial-mediated apoptosis, decrease the proliferation of cancer cells. Many bacterial metabolites have promising anticancer potential. The available research results are promising. However, more research is needed in humans, especially in the child population, to fully understand the relationship between the gut microbiota and acute leukemia. [ABSTRACT FROM AUTHOR]

Grape pomace (GP) is a winemaking by-product particularly rich in (poly)phenols and dietary fiber, which are the main active compounds responsible for its health-promoting effects. These components and their metabolites generated at the intestinal level have been shown to play an important role in promoting health locally and systemically. This review focuses on the potential bioactivities of GP in the intestinal environment, which is the primary site of interaction for food components and their biological activities. These mechanisms include (i) regulation of nutrient digestion and absorption (GP has been shown to inhibit enzymes such as α-amylase and α-glucosidase, protease, and lipase, which can help to reduce blood glucose and lipid levels, and to modulate the expression of intestinal transporters, which can also help to regulate nutrient absorption); (ii) modulation of gut hormone levels and satiety (GP stimulates GLP-1, PYY, CCK, ghrelin, and GIP release, which can help to regulate appetite and satiety); (iii) reinforcement of gut morphology (including the crypt-villi structures, which can improve nutrient absorption and protect against intestinal damage); (iv) protection of intestinal barrier integrity (through tight junctions and paracellular transport); (v) modulation of inflammation and oxidative stress triggered by NF-kB and Nrf2 signaling pathways; and (vi) impact on gut microbiota composition and functionality (leading to increased production of SCFAs and decreased production of LPS). The overall effect of GP within the gut environment reinforces the intestinal function as the first line of defense against multiple disorders, including those impacting cardiometabolic health. Future research on GP's health-promoting properties should consider connections between the gut and other organs, including the gut-heart axis, gut-brain axis, gut-skin axis, and oral-gut axis. Further exploration of these connections, including more human studies, will solidify GP's role as a cardiometabolic health-promoting ingredient and contribute to the prevention and management of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The intestinal epithelium constitutes a selectively permeable barrier between the internal and external environment that allows the absorption of nutrients, electrolytes, and water, as well as an effective defense against intraluminal bacteria, toxins, and potentially antigenic material. Experimental evidence suggest that intestinal inflammation is critically dependent on an imbalance of homeostasis between the gut microbiota and the mucosal immune system. In this context, mast cells play a crucial role. The intake of specific probiotic strains can prevent the development of gut inflammatory markers and activation of the immune system. Here, the effect of a probiotic formulation containing L. rhamnosus LR 32, B. lactis BL04, and B. longum BB 536 on intestinal epithelial cells and mast cells was investigated. To mimic the natural host compartmentalization, Transwell co-culture models were set up. Co-cultures of intestinal epithelial cells interfaced with the human mast cell line HMC-1.2 in the basolateral chamber were challenged with lipopolysaccharide (LPS), and then treated with probiotics. In the HT29/HMC-1.2 co-culture, the probiotic formulation was able to counteract the LPS-induced release of interleukin 6 from HMC-1.2, and was effective in preserving the epithelial barrier integrity in the HT29/Caco-2/ HMC-1.2 co-culture. The results suggest the potential therapeutic effect of the probiotic formulation. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a heterogeneous group of diseases associated with chronic inflammation of the intestinal tract, and is highly prevalent worldwide. Although its origin is not yet fully understood, new evidence emphasizes that environmental factors, especially dietary factors and intestinal microbiota disorders are key triggers of IBD. Probiotics, such as Lactobacillaceae spp., play an essential role in human health as they exert beneficial effects on the composition of the human gastrointestinal microbial community and immune system. Probiotic-based therapies have been shown to be effective in alleviating IBD. Among these, Lactobacillaceae rhamnosus is one of the most widely used strains. L. rhamnosus is widely present in the intestines of healthy individuals; it regulates the intestinal immune system and reduces inflammation through a variety of mechanisms. The purpose of this study was to identify scientific evidence related to L. rhamnosus and IBD, review and summarize the results, and discuss the possible mechanisms of action as a starting point for future research on IBD treatment. [ABSTRACT FROM AUTHOR]

Summary: Autoimmune diseases have long been known to share a common pathogenesis involving a dysregulated immune system with a failure to recognize self from non-self-antigens. This immune dysregulation is now increasingly understood to be induced by environmental triggers in genetically predisposed individuals. Although several external environmental triggers have been defined in different autoimmune diseases, much attention is being paid to the role of the internal micro-environment occupied by the microbiome, which was once termed "the forgotten organ." In this regard, the gut microbiome, serving as an intermediary between some of those external environmental effectors and the immune system, helps programming of the immune system to be tolerant to innocent external and self-antigens. However, in the presence of perturbed gut microbiota (dysbiosis), the immune system could be erroneously directed in favor of pro-inflammatory pathways to instigate different autoimmune processes. An accumulating body of evidence, including both experimental and human studies (observational and interventional), points to the role of the gut microbiome in different autoimmune diseases. Such evidence could provide a rationale for gut microbiome manipulation with therapeutic and even preventative intent in patients with established or predisposed to autoimmune diseases, respectively. Perturbations of the gut microbiome have been delineated in some immune mediated diseases, IBD in particular. However, such patterns of disturbance (microbiome signatures) and related pathogenetic roles of the gut microbiome are context dependent and cannot be generalized in the same exact way to other autoimmune disorders, and the contribution of the gut microbiome to different disease phenotypes has to be precisely defined. In this review, we revise the evidence for a role of the gut microbiome in various autoimmune diseases and possible mechanisms mediating such a role. Several studies point to a role of gut microbiome in the development and progress of different autoimmune diseases. In this review, we revise the evidence and potential mechanism for such a role. This evidence could provide a strong rationale for instigating future clinical trials of gut microbiome manipulation as a therapeutic intervention in patients with established autoimmune diseases. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of a fibre and phenolic‐rich flour (IGF) prepared from Isabel grape by‐products on the growth and metabolism of different probiotics and distinct bacterial populations part of the human intestinal microbiota during an in vitro colonic fermentation. IGF was submitted to simulated gastrointestinal digestion before use in the experiments. IGF favoured the growth of the probiotics Lactobacillus acidophilus La‐05, L. casei L‐26 and Bifidobacterium lactis Bb‐12, with viable counts of >7 log CFU per ml, as well as caused decreases in pH values and increases in organic acid production in the growth medium during 48 h of cultivation. IGF increased the population of beneficial micro‐organisms forming the human intestinal microbiota, particularly Lactobacillus spp., decreased the pH values, and increased the lactic acid and short‐chain fatty acid (acetic, butyric and propionic acids) production during 24 h of in vitro colonic fermentation. These results indicate the potential prebiotic effects of IGF, which should represent a novel sustainable added‐value ingredient with functional properties and gut‐health benefits. [ABSTRACT FROM AUTHOR]

Iron deficiency anemia (IDA) is very common and affects approximately 1/3 of the world's human population. There are strong research data that some probiotics, such as Lactobacillus acidophilus and Bifidobacterium longum improve iron absorption and influence the course of anemia. Furthermore, prebiotics, including galactooligosaccharides (GOS) and fructooligosaccharides (FOS), increase iron bioavailability and decrease its destructive effect on the intestinal microbiota. In addition, multiple postbiotics, which are probiotic metabolites, including vitamins, short-chain fatty acids (SCFA), and tryptophan, are involved in the regulation of intestinal absorption and may influence iron status in humans. This review presents the actual data from research studies on the influence of probiotics, prebiotics, and postbiotics on the prevention and therapy of IDA and the latest findings regarding their mechanisms of action. A comparison of the latest research data and theories regarding the role of pre-, post-, and probiotics and the mechanism of their action in anemias is also presented and discussed. [ABSTRACT FROM AUTHOR]

Aging induces significant shifts in the composition of gut microbiota associated with decreased microbial diversity. Age‐related changes in gut microbiota include a loss of commensals and an increase in disease‐associated pathobionts. These alterations are accelerated by lifestyle factors, such as poor nutritional habits, physical inactivity, and medications. Given that diet is one of the main drivers shaping the gut microbiota, nutritional interventions for restoring gut homeostasis are of great importance to the overall health of older adults. Polyphenols, ubiquitously present in fruits and vegetables, have emerged as promising anti‐aging candidates because of their ability to modulate some of the common denominators of aging, including gut dysbiosis. These compounds can influence the composition of the gut microbiota, and gut bacteria metabolize polyphenols into bioactive compounds that produce relevant health effects. Although the role of polyphenols on the aging gut has not been fully characterized, accumulating evidence suggests that these compounds exert selective effects on the gut microbial community. Here, we discuss the reciprocal interactions between polyphenols and gut microbiota and summarize the latest findings on the effects of polyphenols on modulating intestinal bacteria during aging. [ABSTRACT FROM AUTHOR]

Background: Multiple lines of evidence now support the notion that gut microbiota can contribute to digestive and extra-digestive diseases. The emergence of these observations enabled to postulate a bacteria-centric paradigm to rethink the treatment of many diseases. The goal of therapy should not be to eradicate the flora but to modify it in a way that leads to symptomatic improvement; thus, the interest in the use of probiotics to modulate microbiota composition has increased worldwide in both community and healthcare settings. Summary: The results of published studies are conflicting for most probiotic strains and formulations, and clinicians and consumers need a better understanding of probiotic risks and benefits. Currently, clear guidelines on when to use probiotics and the most effective probiotic for different gastrointestinal conditions are still lacking. Here, we reviewed the studies on the use of probiotics in some diseases of relevant interest to gastroenterologists, such as Helicobacter pylori infection, irritable bowel syndrome, and inflammatory bowel disease. Key Message: Although the evidence is relevant and promising for probiotics in general, and for specific strains and combinations of strains, it is not yet sufficient to draw unequivocal conclusions and clear recommendations. [ABSTRACT FROM AUTHOR]

The prevalence of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), increases gradually worldwide in the past decades. IBD is generally associated with the change of the immune system and gut microbiota, and the conventional treatments usually result in some side effects. Bifidobacterium longum, as colonizing bacteria in the intestine, has been demonstrated to be capable of relieving colitis in mice and can be employed as an alternative or auxiliary way for treating IBD. Here, the mechanisms of the Bifidobacterium longum in the treatment of IBD were summarized based on previous cell and animal studies and clinical trials testing bacterial therapies. This review will be served as a basis for future research on IBD treatment. [ABSTRACT FROM AUTHOR]

The intestinal microbiome changes dynamically in early infancy. Colonisation by Bifidobacterium and Bacteroides and development of intestinal immunity is interconnected. We performed a prospective observational cohort study to determine the influence of antibiotics taken by the mother immediately before delivery on the intestinal microbiome of 130 healthy Japanese infants. Faecal samples (383) were collected at 1, 3, and 6 months and analysed using next-generation sequencing. Cefazolin was administered before caesarean sections, whereas ampicillin was administered in cases with premature rupture of the membranes and in Group B Streptococcus-positive cases. Bifidobacterium and Bacteroides were dominant (60–70% mean combined occupancy) at all ages. A low abundance of Bifidobacterium was observed in infants exposed to antibiotics at delivery and at 1 and 3 months, with no difference between delivery methods. A lower abundance of Bacteroides was observed after caesarean section than vaginal delivery, irrespective of antibiotic exposure. Additionally, occupancy by Bifidobacterium at 1 and 3 months and by Bacteroides at 3 months differed between infants with and without siblings. All these differences disappeared at 6 months. Infants exposed to intrapartum antibiotics displayed altered Bifidobacterium abundance, whereas abundance of Bacteroides was largely associated with the delivery method. Existence of siblings also significantly influenced the microbiota composition of infants. [ABSTRACT FROM AUTHOR]

Hosting millions of microorganisms, the digestive tract is the primary and most important part of bacterial colonization. On one side, in cases of opportunistic invasion, the abundant bacterial population inside intestinal tissues may face potential health problems such as inflammation and infections. Therefore, the immune system has evolved to sustain the host–microbiota symbiotic relationship. On the other hand, to maintain host immune homeostasis, the intestinal microflora often exerts an immunoregulatory function that cannot be ignored. A field of great interest is the association of either microbiota or probiotics with the immune system concerning clinical uses. This microbial community regulates some of the host's metabolic and physiological functions and drives early-life immune system maturation, contributing to their homeostasis throughout life. Changes in gut microbiota can occur through modification in function, composition (dysbiosis), or microbiota–host interplays. Studies on animals and humans show that probiotics can have a pivotal effect on the modulation of immune and inflammatory mechanisms; however, the precise mechanisms have not yet been well defined. Diet, age, BMI (body mass index), medications, and stress may confound the benefits of probiotic intake. In addition to host gut functions (permeability and physiology), all these agents have profound implications for the gut microbiome composition. The use of probiotics could improve the gut microbial population, increase mucus-secretion, and prevent the destruction of tight junction proteins by decreasing the number of lipopolysaccharides (LPSs). When LPS binds endothelial cells to toll-like receptors (TLR 2, 4), dendritic cells and macrophage cells are activated, and inflammatory markers are increased. Furthermore, a decrease in gut dysbiosis and intestinal leakage after probiotic therapy may minimize the development of inflammatory biomarkers and blunt unnecessary activation of the immune system. In turn, probiotics improve the differentiation of T-cells against Th2 and development of Th2 cytokines such as IL-4 and IL-10. The present narrative review explores the interactions between gut microflora/probiotics and the immune system starting from the general perspective of a biological plausibility to get to the in vitro and in vivo demonstrations of a probiotic-based approach up to the possible uses for novel therapeutic strategies. [ABSTRACT FROM AUTHOR]

Objective. Diarrhea in infants is a serious gastrointestinal dysfunction characterized by vomiting and watery bowel movements. Without proper treatment, infants will develop a dangerous electrolyte imbalance. Diarrhea is accompanied by intestinal dysbiosis. This study compared the gut microbiota between healthy infants and diarrheic infants. It also investigated the effects of age and pathogen type on the gut microbiota of infants with diarrhea, providing data for the proper treatment for diarrhea in infants. Materials and Methods. DNA was collected from the fecal samples of 42 Chinese infants with diarrhea and 37 healthy infants. The healthy infants and infants with diarrhea were divided into four age groups: 0–120, 120–180, 180–270, and 270–365 days. Using PCR and 16S rRNA high-throughput sequencing, the diarrhea-causing pathogens in these infants were identified and then categorized into four groups: Salmonella infection, Staphylococcus aureus infection, combined Salmonella and Staphylococcus aureus infection, and others (neither Salmonella nor Staphylococcus aureus). Results. The species diversity of gut microbiota in diarrheic infants was significantly reduced compared with that in healthy infants. Infants with diarrhea had a lower abundance of Lactobacillus spp. and Bacillus spp. (P < 0.001) and a significant richness of Klebsiella spp. and Enterobacter spp. (P < 0.001). Similar gut microbiota patterns were found in diarrheic infants in all four age groups. However, different pathogenic infections have significant effects on the gut microbiota of diarrheic infants. For instance, the relative abundance of Klebsiella spp. and Streptococcus spp. was significantly increased (P < 0.001) in infants infected with Staphylococcus aureus; meanwhile, the richness of bacteria such as Enterobacter spp. was significantly increased in the Salmonella infection group (P < 0.001). Conclusion. The microbiota in infants with diarrhea has changed significantly, characterized by decreased species diversity and abundance of beneficial bacteria and significant increase in the proportion of conditional pathogens. Meanwhile, the gut microbiota of infants with diarrhea at different ages was similar, but different pathogenic infections affect the gut microbiota characteristics. Therefore, early identification of changes in gut microbiota in infants with diarrhea and the adoption of appropriate pathogen type-specific interventions may effectively alleviate the disease and reduce adverse reactions. [ABSTRACT FROM AUTHOR]

Interactions between polyphenols and gut microbiota are indeed a major issue of current interest in food science research. Knowledge in this subject is progressing as the experimental procedures and analysis techniques do. The aim of this article is to critically review the more leading‐edge approaches that have been applied so far in the study of the interactions between grape/wine polyphenols and gut microbiota. This is the case of in vitro dynamic gastrointestinal simulation models that try to mitigate the limitations of simple static models (batch culture fermentations). More complex approaches include the experimentation with animals (mice, rats, pigs, lambs and chicks) and nutritional intervention studies in humans. Main advantages and limitations as well as the most relevant findings achieved by each approach in the study of how grape/wine polyphenols can modulate the composition and/or functionality of gut microbiota, are detailed. Also, common findings obtained by the three approaches (in vitro, animal models and human nutritional interventions) such as the fact that the Firmicutes/Bacteroidetes ratio tends to decrease after the feed/intake/consumption of grape/wine polyphenols are highlighted. Additionally, a nematode (Caenorhabditis elegans) model, previously used for investigating the mechanisms of processes such as aging, neurodegeneration, oxidative stress and inflammation, is presented as an emerging approach for the study of polyphenols interacting gut microbiota. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The gut microbiota plays a prominent role in human health. Alterations in the gut microbiota are linked to the development of chronic diseases such as obesity, inflammatory bowel disease, metabolic syndrome, and certain cancers. We know that diet plays an important role to initiate, shape, and modulate the gut microbiota. Long‐term dietary patterns are shown to be closely related with the gut microbiota enterotypes, specifically long‐term consumption of carbohydrates (related to Prevotella abundance) or a diet rich in protein and animal fats (correlated to Bacteroides). Short‐term consumption of solely animal‐ or plant‐based diets have rapid and reproducible modulatory effects on the human gut microbiota. These alterations in microbiota profile by dietary alterations can be due to impact of different dietary macronutrients, carbohydrates, protein, and fat, which have diverse modulatory effects on gut microbial composition. Food‐derived phenolics, which encompass structural variants of flavonoids, hydroxybenzoic acids, hydroxycinnamic acids, coumarins, stilbenes, ellagitannins, and lignans can modify the gut microbiota. Gut microbes have been shown to act on dietary fibers and phenolics to produce functional metabolites that contribute to gut health. Here, we discuss recent studies on the impacts of phenolics and phenolic fiber‐rich foods on the human gut microbiota and provide an insight into potential synergistic roles between their bacterial metabolic products in the regulation of the intestinal microbiota. [ABSTRACT FROM AUTHOR]

Infection and infection-related complications are important causes of death and morbidity following preterm birth. Despite this risk, there is limited understanding of the development of the immune system in those born prematurely, and of how this development is influenced by perinatal factors. Here we prospectively and longitudinally follow a cohort of babies born before 32 weeks of gestation. We demonstrate that preterm babies, including those born extremely prematurely (<28 weeks), are capable of rapidly acquiring some adult levels of immune functionality, in which immune maturation occurs independently of the developing heterogeneous microbiome. By contrast, we observe a reduced percentage of CXCL8-producing T cells, but comparable levels of TNF-producing T cells, from babies exposed to in utero or postnatal infection, which precedes an unstable post-natal clinical course. These data show that rapid immune development is possible in preterm babies, but distinct identifiable differences in functionality may predict subsequent infection mediated outcomes. The infant immune system is continuously shaped by environmental factors. Here the authors demonstrate that rapid immune development in preterm babies is modulated by perinatal inflammation more than gut microbiota, and that lower CXCL8-producing T cells may identify infants susceptible to infection. [ABSTRACT FROM AUTHOR]

Aims: To evaluate efficacy of Saccharomyces cerevisiae fermentate prebiotic (EH) in protection of intestinal barrier integrity in rats during heat stress, to analyze the impact of heat stress and preventive treatment with EH on the structure of the gut microbiota. Methods and Results: Two groups of rats were treated orally with EH or phosphate‐buffered saline for 14 days. On day 15, half of the rats in each group were exposed to heat stress conditions, while control animals were kept at room temperature. Histological and Western blot analyses of the intestine, culture‐based microbiological analysis and high‐throughput 16S rRNA sequencing for the gut microbiota were performed for each rat. Exposure of animals to heat stress conditions resulted in inhibition of tight junction (TJ) proteins expression, decrease of Paneth and goblet cells, decrease of beneficial and increase of pathogenic bacteria. Oral treatment of rats with EH before stress significantly prevents these adverse effects by elevation of the gut beneficial bacteria, particularly butyrate‐producing bacteria. Conclusions: Essential effect of EH in protection of intestinal barrier integrity during heat stress is connected with beneficial modulation of the gut microbiota. Significance and Impact of the Study: Our results will contribute to the development of new approaches to prevention of heat stress‐related complications. [ABSTRACT FROM AUTHOR]

Background: Preterm infants are especially vulnerable to gut microbiota disruption and dysbiosis since their early gut microbiota is less abundant and diverse. Several factors may influence infants' gut microbiota, such as the mother's diet, mode of delivery, antibiotic exposure, and type of feeding. Objectives: This study aims to examine the factors associated with very-preterm neonate's intestinal microbiota, namely: (1) type of infant-feeding (breast milk, donor human milk with or without bovine protein-based fortifier, and preterm formula); (2) maternal diet; and (3) mode of delivery. Methods: This is an observational study conducted in a cohort of very preterm infants hospitalized in the neonatal intensive care unit of Maternidade Dr. Alfredo da Costa. After delivery, the mothers are asked to collect their own fecal samples and are invited to complete a semiquantitative food frequency questionnaire. The maternal diet will be classified in accordance to the Mediterranean Diet adherence score. Stool samples have been collected from very premature infants every 7 days for 21 days. DNA has been extracted from the fecal samples, and different bacterial genus and species will be quantified by real-time polymerase chain reaction. Results and Conclusions: It is hypothesized that significant differences in the microbiota composition and clinical outcomes of very preterm infants will be observed depending on the type of infant feeding. In addition, this study will clarify how pasteurized donor's milk influences the intestinal microbiota colonization of preterm infants. This is a pioneer study developed in collaboration with the country's Human Milk Bank. We also expect to find microbiota alterations in infants according to the mode of delivery and to maternal diet. This study will contribute to increase the evidence on the effects of breast or donor human milk and its fortification with a bovine protein-based fortifier on infant microbiota. [ABSTRACT FROM AUTHOR]

Inflammatory bowel diseases (IBD) encompass ulcerative colitis (UC), Crohn's disease (CD) and indeterminate colitis (IC), characterising chronic inflammation in the gastrointestinal tract, associated with changes in the immune system and in the intestinal microbiota. Thus, probiotics may offer an alternative or adjuvant approach to conventional therapy. The present review aims to summarise the mechanisms of action of probiotics in IBD and their therapeutic effects. Most of the studies suggest that probiotics are effective in the treatment of UC, especially when several strains are concomitantly administered. Species of Lactobacillus and Bifidobacterium genres are the most commonly used, and some studies even indicate that it is possible to replace medical therapy with probiotic supplementation. Regarding CD, the results of clinical trials are controversial and do not support the use of probiotics in this disease. In conclusion, probiotic supplementation is a promising adjuvant treatment in UC, but not in CD. [ABSTRACT FROM AUTHOR]

Introduction: Although the exact pathophysiological mechanisms of both necrotizing enterocolitis (NEC) and late-onset sepsis (LOS) in preterm infants are yet to be elucidated, evidence is emerging that the gut microbiota plays a key role in their pathophysiology. Areas covered: In this review, initial microbial colonization and factors influencing microbiota composition are discussed. For both NEC and LOS, an overview of studies investigating preclinical alterations in gut microbiota composition and fecal volatile organic compounds (VOCs) is provided. Fecal VOCs are considered to reflect not only gut microbiota composition, but also their metabolic activity and concurrent interaction with the host. Expert review: Heterogeneity in study protocols and applied analytical techniques hampers reliable comparison between outcomes of different microbiota studies, limiting the ability to draw firm conclusions. This dilemma is illustrated by the finding that study results often cannot be reproduced, or even contradict each other. A NEC- and sepsis specific microbial or metabolic signature has not yet been discovered. Identification of ‘disease-specific’ VOCs and microbiota composition may increase understanding on pathophysiological mechanisms and may allow for development of an accurate screening tool, opening avenues towards timely identification and initiation of targeted treatment for preterm infants at increased risk for NEC and sepsis. [ABSTRACT FROM AUTHOR]

Aim: This Lebanese study tested the hypothesis that differences would exist in the gut microbiota of preterm infants with and without necrotising enterocolitis (NEC), as reported in Western countries.Methods: This study compared 11 infants with NEC and 11 controls, all born at 27-35 weeks, in three neonatal intensive care units between January 2013 and March 2015. Faecal samples were collected at key time points, and microbiota was analysed by culture, quantitative PCR (qPCR) and temperature temporal gel electrophoresis (TTGE).Results: The cultures revealed that all preterm infants were poorly colonised and harboured no more than seven species. Prior to NEC diagnosis, significant differences were observed by qPCR with a higher colonisation by staphylococci (p = 0.034) and lower colonisations by enterococci (p = 0.039) and lactobacilli (p = 0.048) in the NEC group compared to the healthy controls. Throughout the study, virtually all of the infants were colonised by Enterobacteriaceae at high levels. TTGE analysis revealed no particular clusterisation, showing high interindividual variability.Conclusion: The NEC infants were poorly colonised with no more than seven species, and the controls had a more diversified and balanced gut microbiota. Understanding NEC aetiology better could lead to more effective prophylactic interventions and a reduced incidence. [ABSTRACT FROM AUTHOR]

The author reflects on importance of the pregnancy period to the development of the neonatal microbiome and host-microbial interactions can impact host metabolism in pregnancy and vaginal delivery exposes infants to microbes that are colonizing the mother's birth canal.

The increasing incidence of inflammatory bowel diseases (IBD) and the increasing severity of the course of these diseases create the need for developing new methods of therapy. The gut microbiome is extensively studied as a factor influencing the development and course of IBD. The composition of intestinal microbiota can be relatively easily modified by diet (i.e., prebiotics, mainly dietary fibers) and bacterial supplementation using beneficial bacteria strains called probiotics. Additionally, the effects of the improved microbiome could be enhanced or gained by using paraprobiotics (non-viable, inactivated bacteria or their components) and/or postbiotics (products of bacterial metabolism or equal synthetic products that beneficially modulate immunological response and inflammation). This study summarizes the recent works on prebiotics, probiotics, synbiotics (products merging pre- and probiotics), paraprobiotics and postbiotics in IBD. [ABSTRACT FROM AUTHOR]

Necrotising enterocolitis (NEC) is the most common gastrointestinal emergency in preterm infants. This contributes to NEC lesions, particularly because the immature intestinal host defences of premature infants predispose them to gut injury.[6] Modulation of gut microbiota may become an efficient preventive approach for NEC pathogenesis.[7]. [Extracted from the article]

There is mounting evidence that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD). For the past decade, high throughput sequencing-based gut microbiome research has identified characteristic shifts in the composition of the intestinal microbiota in patients with IBD, suggesting that IBD results from alterations in the interactions between intestinal microbes and the host's mucosal immune system. These studies have been the impetus for the development of new therapeutic approaches targeting the gut microbiome, such as nutritional therapies, probiotics, fecal microbiota transplant and beneficial metabolic derivatives. Innovative technologies can further our understanding of the role the microbiome plays as well as help to evaluate how the different approaches in microbiome modulation impact clinical responses in adult and pediatric patients. In this review, we highlight important microbiome studies in patients with IBD and their response to different microbiome modulation therapies, and describe the differences in therapeutic response between pediatric and adult patient cohorts. [ABSTRACT FROM AUTHOR]

Two different conditions are included in inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC), being distinguished by chronic recurrence of gut inflammation in persons that are genetically predisposed and subjected to environmental causative factors. The normal structure of the gut microbiome and its alterations in IBD were defined in several microbial studies. An important factor in the prolonged inflammatory process in IBD is the impaired microbiome or "dysbiosis". Thus, gut microbiome management is likely to be an objective in IBD treatment. In this review, we analyzed the existing data regarding the pathophysiological/therapeutic implications of intestinal microflora in the development and evolution of IBD. Furthermore, the main effects generated by the administration of probiotics, prebiotics, fecal transplantation, and phytochemicals supplementation were analyzed regarding their potential roles in improving the clinical and biochemical status of patients suffering from Crohn's disease (CD) and ulcerative colitis (UC), and are depicted in the sections/subsections of the present paper. Data from the literature give evidence in support of probiotic and prebiotic therapy, showing effects such as improving remission rate, improving macroscopic and microscopic aspects of IBD, reducing the pro-inflammatory cytokines and interleukins, and improving the disease activity index. Therefore, the additional benefits of these therapies should not be ignored as adjuvants to medical therapy. [ABSTRACT FROM AUTHOR]

The human intestine contains an intricate community of microorganisms, referred to as the gut microbiota (GM), which plays a pivotal role in host homeostasis. Multiple factors could interfere with this delicate balance, including genetics, age, medicines and environmental factors, particularly diet. Growing evidence supports the involvement of GM dysbiosis in gastrointestinal (GI) and extraintestinal metabolic diseases. The beneficial effects of dietary polyphenols in preventing metabolic diseases have been subjected to intense investigation over the last twenty years. As our understanding of the role of the gut microbiota advances and our knowledge of the antioxidant and anti-inflammatory functions of polyphenols accumulates, there emerges a need to examine the prebiotic role of dietary polyphenols. This review firstly overviews the importance of the GM in health and disease and then reviews the role of dietary polyphenols on the modulation of the gut microbiota, their metabolites and how they impact on host health benefits. Inter-dependence between the gut microbiota and polyphenol metabolites and the vital balance between the two in maintaining the host gut homeostasis are also discussed. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a group of conditions involving chronic relapsing-remitting inflammation of the gastrointestinal tract with an unknown etiology. Although the cause–effect relationship between gut microbiota and IBD has not been clearly established, emerging evidence from experimental models supports the idea that gut microbes play a fundamental role in the pathogenesis of IBD. As microbiome-based therapeutics for IBD, the beneficial effects of probiotics have been found in animal colitis models and IBD patients. In this study, based on the dextran sulfate sodium (DSS)-induced colitis mouse model, we investigated Lactobacillusrhamnosus strain LDTM 7511 originating from Korean infant feces as a putative probiotic strain for IBD. The strain LDTM 7511 not only alleviated the release of inflammatory mediators, but also induced the transition of gut microbiota from dysbiotic conditions, exhibiting the opposite pattern in the abundance of DSS colitis-associated bacterial taxa to the DSS group. Our findings suggest that the strain LDTM 7511 has the potential to be used as a probiotic treatment for IBD patients in comparison to L. rhamnosus GG (ATCC 53103), which has been frequently used for IBD studies. [ABSTRACT FROM AUTHOR]

Alterations of the gut microbiota may cause dysregulated mucosal immune responses leading to the onset of inflammatory bowel diseases (IBD) in genetically susceptible hosts. Restoring immune homeostasis through the normalization of the gut microbiota is now considered a valuable therapeutic approach to treat IBD patients. The customization of microbe-targeted therapies, including antibiotics, prebiotics, live biotherapeutics and faecal microbiota transplantation, is therefore considered to support current therapies in IBD management. In this review, we will discuss recent advancements in the understanding of host−microbe interactions in IBD and the basis to promote homeostatic immune responses through microbe-targeted therapies. By considering gut microbiota dysbiosis as a key feature for the establishment of chronic inflammatory events, in the near future it will be suitable to design new cost-effective, physiologic, and patient-oriented therapeutic strategies for the treatment of IBD that can be applied in a personalized manner. [ABSTRACT FROM AUTHOR]

Background: Necrotising enterocolitis (NEC) is a common cause of death in preterm infants and is closely linked to the gut microbiota. Spontaneous intestinal perforation (SIP) also occurs in preterm neonates, but results in lower mortality and less adverse neonatal outcomes than NEC. Existing studies are largely limited to non-invasive stool samples, which may not be reflective of the anatomical site of disease. Therefore, we analysed historical formalin-fixed paraffin-embedded (FFPE) tissue from NEC and SIP preterm infants. A total of 13 NEC and 16 SIP infants were included. Extracted DNA from FFPE tissue blocks underwent 16S rRNA gene sequencing. For a subset of infants, diseased tissue and marginal healthy tissue from the same infant were compared. Results: Xylene provided a cost and time effective means of deparaffinization. Tissue from the site of disease was highly comparable to adjacent healthier tissue. Comparing only diseased tissue from all infants showed significantly lower Shannon diversity in NEC (P = 0.026). The overall bacterial communities were also significantly different in NEC samples compared to SIP (P = 0.038), and large variability within NEC infants was observed. While no single OTU or genus was significantly associated with NEC or SIP, at the phylum level Proteobacteria (P = 0.045) and Bacteroidetes (P = 0.024) were significantly higher in NEC and SIP infants, respectively. Conclusions: Existing banks of intestinal FFPE blocks provide a robust and specific sample for profiling the microbiota at the site of disease. We showed preterm infants with NEC have lower diversity and different bacterial communities when compared to SIP controls. [ABSTRACT FROM AUTHOR]

Increased arterial stiffness is a degenerative vascular process, progressing with age that leads to a reduced capability of arteries to expand and contract in response to pressure changes. This progressive degeneration mainly affects the extracellular matrix of elastic arteries and causes loss of vascular elasticity. Recent studies point to significant interference of dietary polyphenols with mechanisms involved in the pathophysiology and progression of arterial stiffness. This review summarizes data from epidemiological and interventional studies on the effect of polyphenols on vascular stiffness as an illustration of current research and addresses possible etiological factors targeted by polyphenols, including pathways of vascular functionality, oxidative status, inflammation, glycation, and autophagy. Effects can either be inflicted directly by the dietary polyphenols or indirectly by metabolites originated from the host or microbial metabolic processes. The composition of the gut microbiome, therefore, determines the resulting metabolome and, as a consequence, the observed activity. On the other hand, polyphenols also influence the intestinal microbial composition, and therefore the metabolites available for interaction with relevant targets. As such, targeting the gut microbiome is another potential treatment option for arterial stiffness. [ABSTRACT FROM AUTHOR]

Glycoproteins are major players in the mucus protective barrier in the gastrointestinal and other mucosal surfaces. In particular the mucus glycoproteins, or mucins, are responsible for the protective gel barrier. They are characterized by their high carbohydrate content, present in their variable number, tandem repeat domains. Throughout evolution the mucins have been maintained as integral components of the mucosal barrier, emphasizing their essential biological status. The glycosylation of the mucins is achieved through a series of biosynthetic pathways processes, which generate the wide range of glycans found in these molecules. Thus mucins are decorated with molecules having information in the form of a glycocode. The enteric microbiota interacts with the mucosal mucus barrier in a variety of ways in order to fulfill its many normal processes. How bacteria read the glycocode and link to normal and pathological processes is outlined in the review. [ABSTRACT FROM AUTHOR]

The high diversity of phenolic compounds (PC) found in food matrices makes it challenging to analyze their bioavailability and their impact on health and functional metabolism. It is well recognized that PC do modulate the composition of the gut microbiota (GM), however, the literature still lacks significant data concerning the link between the metabolic fate of the ingested compounds and their bioactivity, mainly when considering the secondary metabolites produced. In this study, we assessed the metabolic fate of PC for a period covering 14 months of daily intake to identify the metabolites that could be responsible for the effects of PC on the GM observed in our previous work. Urinary analysis of polyphenol metabolites was performed using a high resolution mass spectrometry LC-QTOF-MS method. Among the sixteen metabolites identified, 3-hydroxyphenylacetic acid and 2-(4-hydroxyphenyl) propionic acid were detected simultaneously and, therefore, correlated with the growth of Bifidobacterium in the rat GM. In addition, Daidzedin, detected only at 14 months post-treatment, mostly interfered with the growth inhibition of Clostridium (Cluster I). In conclusion, the impact of the long-term intake of PC on rat GM seems to be related to specific metabolites produced after ingestion of the parental compounds and this may also be due to their additional synergistic effects. [ABSTRACT FROM AUTHOR]