Investigating the mechanism of enhanced medicinal effects of Terminalia chebula fruit after processing based on intestinal flora and metabolomics.

BACKGROUND AND OBJECTIVE: Terminalia chebula is a classical medicine for the treatment of lingering dysentery, and both raw and processed T. chebula can alleviate ulcerative colitis (UC). The therapeutic efficacy of T. chebula is enhanced after processing, but the mechanism that processing improves this efficacy is still unknown. We investigated the medicinal effects of raw and processed T. chebula on dextran sulfate sodium (DSS)-induced UC model rats using intestinal flora and metabolomics analyses, in order to elucidate the mechanism by which processing enhances the therapeutic effect. METHODS: The major constituents of raw and processed T. chebula were detected by high-performance liquid chromatography (HPLC). UC model was replicated using the DSS method, and then UC rats were administered raw and processed T. chebula. The general physical signs, disease activity index (DAI) scores, colon histopathological morphology, and the expressions of inflammatory cytokines were used to evaluate the therapeutic effect of T. chebula. In addition, 16 s rRNA sequencing and gas chromatography-mass spectrometry (GC-MS) were used to characterize the intestinal flora and contents of short-chain fatty acids (SCFAs). Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was utilized to identify the nontargeted fecal metabolites. RESULTS: Raw and processed T. chebula significantly improved the general physical signs and colon inflammatory symptoms and decreased DAI scores of UC rats. Both raw and processed T. chebula mitigated intestinal flora disorders in UC rats, increasing probiotic bacteria, including Lactobacillus and Romboutsia. However, the effect of processed T. chebula was more pronounced. Moreover, the levels of SCFAs of DSS-induced UC rats were restored after drug administration, and the processed T. chebula had a better regulatory effect than raw T. chebula. In the fecal nontargeted metabolomics analysis, differential metabolites such as lipids and amino acids were identified. The processed T. chebula can regulate purine metabolism and other pathways to improve UC, and the levels of the disordered metabolites gradually approached those of the control group. CONCLUSION: Raw and processed T. chebula had the capacity to mitigate DSS-induced UC by rebalancing the intestinal flora, restoring the contents of SCFAs, and regulating fecal metabolites, while processed T. chebula showed preferable effects.

The short-chain fatty acid receptors Gpr41/43 regulate bone mass by promoting adipogenic differentiation of mesenchymal stem cells.

Bone is a dynamic tissue that is constantly remodeled throughout adult life. Recently, it has been shown that bone turnover decreases shortly after food consumption. This process has been linked to the fermentation of non-digestible food ingredients such as inulin by gut microbes, which results in the production of the short-chain fatty acids (SCFAs) acetate, propionate and butyrate. SCFAs exert various metabolic functions, which in part can be explained by activation of G protein-coupled receptors (Gpr) 41 and 43. However, the potential relevance of a SCFA-Gpr41/43 signaling axis for bone metabolism has not been established. The aim of our study is to investigate the role of Gpr41/43 in bone metabolism and osteogenic differentiation of mesenchymal stem cells. For this purpose, we analyzed the skeletal phenotype of wild type controls (WT) and Gpr41/43 double knockout (Gpr41/43 dKO) mice fed either a chow or an inulin-enriched diet. In addition, we isolated bone marrow derived mesenchymal stem cells from WT and Gpr41/43 dKO mice and differentiated them into osteoblasts in the absence or presence of acetate. MicroCT scanning of femoral bones of Gpr41/43 dKO mice revealed a significant increase of trabecular bone volume and trabecular compared to WT controls. Treatment of WT bone marrow-derived osteoblasts with acetate resulted in decreased mineralization and substantial downregulation of bone formation markers such as Phex, Ptgs2 and Col1a1. Notably, this effect was strongly attenuated in differentiated osteoblasts lacking Gpr41/43. Inversely, acetate supplementation resulted in higher levels of adipocyte marker genes including Pparg, Lpl and Adipoq in bone marrow-derived cells from WT mice, an effect blunted in differentiated cells isolated from Gpr41/43 dKO mice. Overall, these data indicate that acetate regulates bone architecture via SCFA-Gpr41/43 signaling by modulating the osteogenic versus adipogenic differentiation of mesenchymal stem cells.

The role of gut microbiota in prostate inflammation and benign prostatic hyperplasia and its therapeutic implications.

Background: The gut microbiota thrives in a complex ecological environment and its dynamic balance is closely related to host health. Recent studies have shown that the occurrence of various diseases including prostate inflammation is related to the dysregulation of the gut microbiome. Objective: This review focus on the mechanisms by which the gut microbiota induces prostate inflammation and benign prostatic hyperplasia and its therapeutic implications. Materials and methods: Publications related to gut microbiota, prostate inflammation, and benign prostatic hyperplasia (BPH) until April 2023 were systematically reviewed. The research questions were formulated using the Problem, Intervention, Comparison/Control, and Outcome (PICO) frameworks. Results: Fifteen articles covering the relationship between the gut microbiota and prostate inflammation/BPH, the mechanisms by which the gut microbiota influences prostate inflammation and BPH, and potential therapeutic approaches targeting the gut microbiota for these conditions were included. Conclusion: Short-chain fatty acids (SCFAs), which are metabolites of the intestinal microbiota, protect the integrity of the intestinal barrier, regulate immunity, and inhibit inflammation. However, dysregulation of the gut microbiota significantly reduces the SCFA content in feces and impairs the integrity of the gut barrier, leading to the translocation of bacteria and bacterial components such as lipopolysaccharide, mediating the development of prostate inflammation through microbe-associated molecular patterns (MAMPs).

Lycopene attenuates D-galactose-induced memory and behavioral deficits by mediating microbiota-SCFAs-gut-brain axis balance in female CD-1 mice.

Aging impairs cognitive function, whereas nutritional intervention can delay aging and age-related diseases. Lycopene (LYC), a naturally occurring carotenoid, posses multiple health-promoting properties, including neuroprotective function. Here, the effects of LYC on memory and behavioral deficits induced by D-galactose (D-gal) treatment and the relative contribution of LYC-derived gut microbiota in these process were investigated. Results demonstrated that LYC showed effective protection on D-gal induced cognitive deficit and neuronal damage. Moreover, LYC treatment has beneficial effects on gut barrier damage, microbiota dysbiosis and levels of SCFAs in D-gal-induced subacute aging mice. Next, fecal microbiota transplantation (FMT) experiment was performed and increased SCFAs were observed in mice received stools from D-gal+LYC group when compared with D-gal-FMT group. Thus, we added SCFAs treatment served as a control group in order to evaluated whether the alterations of gut-brain axis could be attributed to LYC-reshaped gut microbiota and SCFAs. Results showed that recipient mice received SCFAs and stools from D-gal+LYC group have similar beneficial effects in improving gut and brain function, demonstrated as: improved intestinal health via elevating antioxidant enzymes contents, increasing the expressions of tight junctions proteins and protecting gut barrier, enhanced mice working memory capacity via alleviating hippocampal neurons impairment, improving synaptic function and enhancing mitochondrial function in the intestinal pseudo-aseptic mice. In conclusion, our results demonstrated that LYC-derived microbiome played a pivotal role in the regulation of cognitive functions during aging and enhanced SCFAs formation might be an important signaling molecule connecting gut microbiome and brain.

Gastrointestinal microbiota and metabolites responses to dietary cereal grains in an adult pig model.

Corn (C), wheat (W), and paddy rice (PR) are important energy sources and are commonly used in feed production for swine. This study mainly focuses on the variation and regularities of microbiota and metabolites in the gastrointestinal tract (GIT) of pigs in response to C, W, and PR. A total of 18 pigs were allotted into three dietary groups with six replicated pigs and received diets containing C, W, or PR as the sole energy source, respectively. The results showed that digestive parts significantly affected the diversity of microbial communities. Cereal grain sources significantly influenced the ß-diversity of microbial communities in the colon and rectum. Campylobacterota and Proteobacteria are mainly distributed in the duodenum, Lactobacillus in the jejunum, and Bacteroidota in the colon and rectum. The W diet increased the Bacteroidota, Spirochaetota, and Prevotellaceae_NK3B31_group abundances and showed the highest concentrations of all short-chain fatty acids (SCFAs) in the hindgut. Fibrobacterota, Bacteroidota, Spirochaetota, Prevotellaceae_NK3B31_group, Prevotella, and Treponema in the colon or rectum were positively correlated with acetate, propionate, butyrate, and total SCFAs. These findings suggested that aerobic bacteria and facultative anaerobes in the foregut will gradually be replaced by anaerobes in the hindgut. The W diet had the best fermentability and was beneficial to the colonization of microbial communities that mainly used carbohydrates. The hindgut flora of the PR diet group may be more balanced with fewer potential pathogenic bacteria. Many microbial communities have been identified to contribute positively to the SCFA production of the hindgut. Collectively, our study revealed the spatial variation regularities of GIT microbial communities in an adult pig model and provided new insights into GIT microbiota and responses of metabolites to cereal grain diets.

Cross-talk between macrophages and gut microbiota in inflammatory bowel disease: a dynamic interplay influencing pathogenesis and therapy.

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is a group of chronic immune-mediated gastrointestinal disorders. The etiology of IBD is multifactorial, involving genetic susceptibility, environmental factors, and a complex interplay between the gut microbiota and the host's immune system. Intestinal resident macrophages play an important role in the pathogenesis and progress of IBD, as well as in maintaining intestinal homeostasis and facilitating tissue repair. This review delves into the intricate relationship between intestinal macrophages and gut microbiota, highlighting their pivotal roles in IBD pathogenesis. We discuss the impact of macrophage dysregulation and the consequent polarization of different phenotypes on intestinal inflammation. Furthermore, we explore the compositional and functional alterations in gut microbiota associated with IBD, including the emerging significance of fungal and viral components. This review also examines the effects of current therapeutic strategies, such as 5-aminosalicylic acid (5-ASA), antibiotics, steroids, immunomodulators, and biologics, on gut microbiota and macrophage function. We underscore the potential of fecal microbiota transplantation (FMT) and probiotics as innovative approaches to modulate the gut microbiome in IBD. The aim is to provide insights into the development of novel therapies targeting the gut microbiota and macrophages to improve IBD management.

Enhancing short-chain fatty acids production from waste activated sludge anaerobic fermentation with addition of red mud: Performance and mechanisms.

Red mud (RM) as hazardous waste produced from aluminum refining industry has threatened the environment and human health. In this study, RM was added into the fermenter to promote short chain fatty acids (SCFAs) production from waste activated sludge (WAS) anaerobic fermentation. Results showed that the addition of RM could effectively improve the SCFAs production, especially, acetic acid. In particular, the production of total SCFAs and acetic acid in 20 g/L RM added fermenter were 1108.1 mg COD/L and 415.5 mg COD/L, which were 116.0% and 1308.0% higher than that in control fermenter. Batch experiment revealed that RM could enhance the hydrolysis and acidification process. Further study indicated that the activity of enzyme related to hydrolysis-acidification, abundance of fermentative bacteria for SCFAs production and functional metabolism genome were all improved with the addition of RM. The potential mechanism maybe that the RM promoted the hydrolysis-acidification process with the contained varies Fe(Ⅲ) oxides as electron acceptor, and the produced Fe2+ could serve as necessary trace elements to synthesize enzyme and then stimulate the expression of enzyme genes.

Aged garlic oligosaccharides modulate host metabolism and gut microbiota to alleviate high-fat and high-cholesterol diet-induced atherosclerosis in ApoE-/- mice.

Atherosclerosis (AS) is a cardiovascular disease caused by excessive accumulation of lipids in arterial walls. In this study, we developed an AS model in ApoE-/- mice using a high-fat, high-cholesterol diet and investigated the anti-AS mechanism of aged garlic oligosaccharides (AGOs) by focusing on the gut microbiota. Results revealed that AGOs exhibited significant anti-AS effects, reduced trimethylamine N-oxide levels from 349.9 to 189.2 ng/mL, and reduced aortic lipid deposition from 31.7 % to 9.5 %. AGOs significantly increased the levels of short-chain fatty acids in feces, in which acetic, propionic, and butyric acids were increased from 1.580, 0.364, and 0.469 mg/g to 2.233, 0.774, and 0.881 mg/g, respectively. An analysis of the gut microbiota indicated that AGOs restored alpha and beta diversity, decreased the Firmicutes/Bacteroidetes ratio, and promoted the dominance of the genus Akkermansia. A metagenomic analysis revealed that AGOs alleviated AS through the ABC transporter pathway and the lipopolysaccharide biosynthesis pathway.

The pectin metabolizing capacity of the human gut microbiota.

The human gastrointestinal microbiota, densely populated with a diverse array of microorganisms primarily from the bacterial phyla Bacteroidota, Bacillota, and Actinomycetota, is crucial for maintaining health and physiological functions. Dietary fibers, particularly pectin, significantly influence the composition and metabolic activity of the gut microbiome. Pectin is fermented by gut bacteria using carbohydrate-active enzymes (CAZymes), resulting in the production of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate, which provide various health benefits. The gastrointestinal microbiota has evolved to produce CAZymes that target different pectin components, facilitating cross-feeding within the microbial community. This review explores the fermentation of pectin by various gut bacteria, focusing on the involved transport systems, CAZyme families, SCFA synthesis capacity, and effects on microbial ecology in the gut. It addresses the complexities of the gut microbiome's response to pectin and highlights the importance of microbial cross-feeding in maintaining a balanced and diverse gut ecosystem. Through a systematic analysis of pectinolytic CAZyme production, this review provides insights into the enzymatic mechanisms underlying pectin degradation and their broader implications for human health, paving the way for more targeted and personalized dietary strategies.

The interaction between gut microbiota and hibernation in mammals.

Hibernation, an evolved survival trait among animals, enables them to endure frigid temperatures and food scarcity during the winter months, and it is a widespread phenomenon observed in mammals. The gut microbiota, a crucial component of animal nutrition and health, exhibits particularly dynamic interactions in hibernating mammals. This manuscript comprehensively evaluates the impacts of fasting, hypothermia, and hypometabolism on the gut microbiota of hibernating mammals. It suggests that alterations in the gut microbiota may contribute significantly to the maintenance of energy metabolism and intestinal immune function during hibernation, mediated by their metabolites. By delving into these intricacies, we can gain a deeper understanding of how hibernating mammals adapt to their environments and the consequences of dietary modifications on the symbiotic relationship between the gut microbiota and the host. Additionally, this knowledge can inform our comprehension of the protective mechanisms underlying long-term fasting in non-hibernating species, including humans, providing valuable insights into nutritional strategies and health maintenance.

Comprehensive modulatory effects of whole grain consumption on immune-mediated inflammation in middle-aged and elderly community residents: A real-world randomized controlled trial.

BACKGROUND AND AIMS: Whole grain consumption is widely recognized as a vital component of a balanced diet. Dietary fiber has been well-documented to play a crucial role in these health benefits attributed to whole grain intake. However, population-based evidence directly linking whole grain consumption to anti-inflammatory effects, especially in the context of immune-mediated inflammation, remains limited. We hypothesized that whole grain consumption promotes health by modulating immune-mediated inflammation. METHODS AND RESULTS: This study was designed as a real-world, population-based randomized controlled trial. We compared the effects of whole grain versus refined grain consumption on immune-mediated inflammation through staple food substitution, while participants maintained their usual dietary practices. The results demonstrated that whole grain consumption significantly reduced circulating levels of pro-inflammatory cytokines IL-22 and IL-23 compared to refined grain consumption. These reductions were associated with optimized short-chain fatty acid profiles and changes in CD4+ T cell subset distributions. CONCLUSIONS: The findings suggest that the anti-inflammatory effects of whole grain consumption in middle-aged and elderly populations are mediated by targeting specific CD4+ T cell subsets, in addition to modulating both upstream short-chain fatty acid composition and downstream expression of the pro-inflammatory cytokines IL-22 and IL-23.

Gut-muscle axis mechanism of exercise prevention of sarcopenia.

Sarcopenia refers to an age-related systemic skeletal muscle disorder, which is characterized by loss of muscle mass and weakening of muscle strength. Gut microbiota can affect skeletal muscle through a variety of mechanisms. Gut microbiota present distinct features among elderly people and sarcopenia patients, including a decrease in microbial diversity, which might be associated with the quality and function of the skeletal muscle. There might be a gut-muscle axis; where gut microbiota and skeletal muscle may affect each other bi-directionally. Skeletal muscle can affect the biodiversity of the gut microbiota, and the latter can, in turn, affect the anabolism of skeletal muscle. This review examines recent studies exploring the relationship between gut microbiota and skeletal muscle, summarizes the effects of exercise on gut microbiota, and discusses the possible mechanisms of the gut-muscle axis.

Salivary Short-chain Fatty Acids (SCFAs) Are Viable Predictors of Early Changes in Systemic Health.

Short-chain fatty acids (SCFAs) are the metabolites identified in both the oral cavity and the gut. They play an important role in the triggering, development and progression of systemic diseases. SCFAs can alter the gut microbial components, intestinal epithelium and host immune system, and are also associated with cancer incidence. Salivary SCFAs, produced by the oral microbiome, are correlated with some oral diseases. The occurrence of systemic diseases associated with gut SCFAs is more clearly defined than oral SCFAs. Salivary SCFAs can enter the bloodstream directly via inflamed gingiva to cause continuous low-grade systemic inflammation. Hence, salivary SCFAs could be an indicator for the early diagnosis of systemic diseases. Furthermore, they provide a basis for understanding the oral-systemic axis driven through salivary SCFAs in the pathogenesis of several diseases.

Exposure to greenspaces sourced soils improves mice gut microbiota.

Greenspaces are important components of our living environment and have been linked to various human health. However, the mechanisms underlying the linkages remain unclear. Enriching microbiota has emerged as a novel mechanism, but the corresponding evidence is still limited. We collected soil samples from forest land, grassland, and barren land in Zunyi City, southwestern China and prepared soil solutions. A total of 40 BALB/c mice were evenly divided into normal control group, model control group, forest soil group, grassland soil group, and barren land soil group. After establishing the pseudo germ-free mouse model, different soil solutions were administered through gavage, lasting for seven weeks. Fecal samples were collected and a 16S rRNA high-throughput sequencing analysis was performed. Then, alpha- and beta-diversity were calculated and employed to estimate the effects of soil exposures on mice gut microbial diversity and composition. Further, Linear Discriminant Analysis Effect Size (LEfSe) analysis was carried out to evaluate the effects of soil exposures on gut microbiota specific genera abundances and functional pathways. Compared to mice exposed to barren land soils, those exposed to soils sourced from forest land showed an increase of 0.43 and 70.63 units in the Shannon index and the Observed ASVs, respectively. In addition, exposure to soils sourced from forest land and grassland resulted in healthier changes (i.e., more short-chain fatty acids (SCFAs)-producing bacteria) in gut microbiota than those from barren land. Furthermore, mice exposed to forest soil and grassland soil showed enrichment in 5 and 3 pathways (e.g., butanoate metabolism) compared to those exposed to barren land soil, respectively. In conclusion, exposure to various greenspaces soils may modify the gut microbial communities of mice, potentially fostering a more beneficial microbiota profile. Further better-designed studies are needed to validate the current findings and to explore the effects of greenspace related gut microbiota on human health.

Oat anthranilamides regulates high-fat diet-induced intestinal inflammation by the TLR4/NF-κb signalling pathway and gut microbiota.

Oat anthranilamides have demonstrated antioxidant and anti-inflammatory effects; however, the precise mechanism of action remains unclear. This study investigated the impact of oat anthranilamide B (AVN B) on high-fat diet (HFD)-induced intestinal inflammation in mice and its underlying mechanisms. The results indicated that AVN B supplementation mitigated weight gain and reduced inflammatory and oxidative stress markers in serum, liver, and intestines. It improved intestinal barrier dysfunction by upregulating the expression levels of Occludin and MUC2 while simultaneously reducing intestinal inflammation by inhibiting the TLR4/NF-κB signalling pathway. Additionally, AVN B treatment improved gut microbiota composition. It increased the abundance of beneficial flora and the production of short-chain fatty acids (SCFAs), especially propionate and butyrate, associated with reduced production of pro-inflammatory factors and enhanced intestinal protection. The findings provide scientific evidence for the potential of AVN B as an anti-inflammatory agent.

Oat AVN B reduces body weight gain and inflammation levels in HFD-fed miceAVN B protects the intestinal barrier and inhibits intestinal inflammationAVN B inhibits TLR4/NF-κB signalling pathway in the ileum of HFD-induced miceAVN B improves gut microbial imbalance in HFD-induced miceAVN B increases butyrate and propionic acid by promoting SCFA-producing bacteria.

The prebiotic effects of fructooligosaccharides enhance the growth characteristics of Staphylococcus epidermidis and enhance the inhibition of Staphylococcus aureus biofilm formation.

OBJECTIVE: Oligosaccharides have been shown to enhance the production of short chain fatty acids (SCFAs) by gut probiotics and regulate gut microbiota, to improve intestinal health. Recent research indicates that oligosaccharides may also positively impact skin microbiota by selectively promoting the growth of skin commensal bacteria and inhibiting pathogenic bacteria. However, the specific metabolic and regulatory mechanisms of skin commensal bacteria in response to oligosaccharides remain unclear. This study aims to explore the influence of four oligosaccharides on the growth and metabolism of Staphylococcus epidermidis and further identify skin prebiotics that can enhance its probiotic effects on the skin. METHODS: Fructooligosaccharides (FOS), isomaltooligosaccharide (IMO), galactooligosaccharides (GOS) and inulin were compared in terms of their impact on cell proliferation, SCFAs production of S. epidermidis CCSM0287 and the biofilm inhibition effect of their fermentation supernatants on Staphylococcus aureus CCSM0424. Furthermore, the effect of FOS on S. epidermidis CCSM0287 was analysed by the transcriptome analysis. RESULTS: All four oligosaccharides effectively promoted the growth of S. epidermidis CCSM0287 cells, increased the production of SCFAs, with FOS demonstrating the most significant effect. Analysis of the SCFAs indicated that S. epidermidis CCSM0287 predominantly employs oligosaccharides to produce acetic acid and isovaleric acid, differing from the SCFAs produced by gut microbiota. Among the four oligosaccharides, the addition of 2% FOS fermentation supernatant significantly inhibited S. aureus CCSM0424 biofilm formation. Furthermore, RNA sequencing revealed 162 differentially expressed genes (84 upregulated and 78 downregulated) of S. epidermidis CCSM0287 upon FOS treatment compared with glucose treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis highlighted differences in the amino acid synthesis pathway, particularly in terms of arginine biosynthesis. CONCLUSION: FOS promotes cell proliferation, increases the SCFA production of S. epidermidis CCSM0287 and enhance the inhibition of S. aureus biofilm formation, suggesting that FOS serves as a potential prebiotic for strain S. epidermidis CCSM0287.

OBJECTIF: Il a été démontré que les oligosaccharides améliorent la production d'acides gras à chaîne courte (AGCC) par les probiotiques intestinaux et régulent le microbiote intestinal, pour améliorer la santé intestinale. Des recherches récentes indiquent que les oligosaccharides peuvent également avoir un impact positif sur le microbiote cutané en favorisant sélectivement la croissance des bactéries commensales de la peau et en inhibant les bactéries pathogènes. Cependant, les mécanismes métaboliques et régulateurs spécifiques des bactéries commensales de la peau en réponse aux oligosaccharides restent incertains. Cette étude vise à étudier l'influence de quatre oligosaccharides sur la croissance et le métabolisme de Staphylococcus epidermidis, et à identifier de manière plus approfondie les prébiotiques cutanés qui peuvent améliorer ses effets probiotiques sur la peau. MÉTHODES: Les fructooligosaccharides (FOS), les isomaltooligosaccharides (IMO), les galactooligosaccharides (GOS) et l'inuline ont été comparés en termes d'impact sur la prolifération cellulaire, de production d'AGCC du S. epidermidis CCSM0287 et d'effet d'inhibition du biofilm de leurs surnageants de fermentation sur le staphylococoque CCSM0424. En outre, l'effet des FOS sur S. epidermidis CCSM0287 a été analysé par analyse du transcriptome. RÉSULTATS: Les quatre oligosaccharides ont efficacement favorisé la croissance des cellules du S. epidermidis CCSM0287, augmenté la production d'AGCC, le FOS démontrant l'effet le plus significatif. L'analyse des AGCC a indiqué que S. epidermidis CCSM0287 emploie principalement des oligosaccharides pour produire de l'acide acétique et de l'acide isovalérique, ce qui diffère des AAGC produites par le microbiote intestinal. Parmi les quatre oligosaccharides, l'ajout d'un surnageant de fermentation de FOS à 2% a inhibé significativement la formation du biofilm de S. aureus CCSM0424. En outre, le séquençage de l'ARN a révélé 162 gènes exprimés de manière différentielle (84 régulés à la hausse et 78 régulés à la baisse) de S. epidermidis CCSM0287 lors du traitement par FOS par rapport au traitement par glucose. L'analyse d'enrichissement de Kyoto Encyclopedia of Genes and Genomes (KEGG) a mis en évidence des différences dans la voie de synthèse des acides aminés, en particulier en termes de biosynthèse de l'arginine. CONCLUSION: Le FOS favorise la prolifération cellulaire, augmente la production des AGCC du S. epidermidis CCSM0287 et améliore l'inhibition de la formation du biofilm de S. aureus, ce qui indique que le FOS sert de prébiotique potentiel pour la souche S. epidermidis CCSM0287.

Chemical structure and prebiotic activity of a Dictyophora indusiata polysaccharide fraction.

This study aimed to investigate the chemical structure and prebiotic activity of a Dictyophora indusiata polysaccharide fraction DIP0p. Our results indicated that DIP0p belongs to a heteropolysaccharide composed of glucose, galactose, mannose and xylose, accounting for 53.25 %, 24.18 %, 19.19 % and 3.37 %, respectively. Methylation and NMR results suggested that the main glycosidic bonds of DIP0p is →3)-Glcp-(1 â†’ with →4)-Glcp-(1→, →3,4)-Glcp-(1→, →3,4)-Galp-(1 â†’ and →6)-Manp-(1 â†’ branches. In addition, DIP0p increased the abundance of benificial bacteria during the in vitro fecal fermentation, including Phascolarctobacterium, Parabacteroides and Bifidobacterium. It is remarkable that DIP0p improved the level of acetic acid, propionic acid, and butyric acid of the fermentation system, which were 1.31, 1.52, and 2.64 folds higher than the Controls, respectively. In summary, this study comprehensively analyzed the structure and probiotic activity of DIP0p, which providing a theoretical basis for the development of the functional foods.

The interplay between gut microbiota, short-chain fatty acids, and implications for host health and disease.

Short-chain fatty acids (SCFAs) - acetate, propionate, and butyrate - are important bacterial fermentation metabolites regulating many important aspects of human physiology. Decreases in the concentrations of any or multiple SCFAs are associated with various detrimental effects to the host. Previous research has broadly focused on gut microbiome produced SCFAs as a group, with minimal distinction between acetate, propionate, and butyrate independently, each with significantly different host effects. In this review, we comprehensively delineate the roles of these SCFAs with emphasis on receptor affinity, signaling pathway involvement, and net host physiologic effects. Butyrate is highlighted due to its unique role in gastrointestinal-associated functions, especially maintaining gut barrier integrity. Butyrate functions by promoting epithelial tight junctions, serving as fuel for colonocyte ATP production, and modulating the immune system. Interaction with the immune system occurs locally in the gastrointestinal tract and systemically in the brain. Investigation into research conducted on butyrate production pathways and specific bacterial players involved highlights a unique risk associated with use of gram-positive targeted antibiotics. We review and discuss evidence showing the relationship between the butyrate-producing gram-positive genus, Roseburia, and susceptibility to commonly prescribed, widely used gram-positive antibiotics. Considering gut microbiome implications when choosing antibiotic therapy may benefit health outcomes in patients.

Advances in the mechanism of action of short-chain fatty acids in psoriasis.

Psoriasis is a prevalent chronic inflammatory and immunological disorder. Its lesions are present as scaly erythema or plaques. Disruptions in the body's immune system play a significant role in developing psoriasis. Recent evidence suggests a potential role of the gut microbiome in autoimmune diseases. Short-chain fatty acids (SCFAs) are the primary metabolites created by gut microbes and play a crucial fuction in autoimmunity. SCFAs act on various cells by mediating signaling to participate in host physiological and pathological processes. These processes encompass body metabolism, maintenance of intestinal barrier function, and immune system modulation. SCFAs can regulate immune cells to enhance the body's immune function, potentially influencing the prevention and treatment of psoriasis. However, the mechanisms underlying the role of SCFAs in psoriasis remain incompletely understood. This paper examines the relationship between SCFAs and psoriasis, elucidating how SCFAs influence the immune system, inflammatory response, and gut barrier in psoriasis. According to the study, in psoriasis, SCFAs have been shown to regulate neutrophils, macrophages, and dendritic cells in the adaptive immune system, as well as T and B cells in the innate immune system. Additionally, we explore the role of SCFAs in psoriasis by maintaining intestinal barrier function, restoring intestinal ecological homeostasis, and investigating the potential therapeutic benefits of SCFAs for psoriasis.

The intestinal microbiome of infants with cow's milk-induced FPIES is enriched in taxa and genes of enterobacteria.

OBJECTIVES: Food protein-induced enterocolitis syndrome (FPIES) is a severe type of non-IgE (immunoglobulin E)-mediated (NIM) food allergy, with cow's milk (CM) being the most common offending food. The relationship between the gut microbiota and its metabolites with the inflammatory process in infants with CM FPIES is unknown, although evidence suggests a microbial dysbiosis in NIM patients. This study was performed to contribute to the knowledge of the interaction between the gut microbiota and its derived metabolites with the local immune system in feces of infants with CM FPIES at diagnosis. METHODS: Twelve infants with CM FPIES and a matched healthy control group were recruited and the gut microbiota was investigated by 16S amplicon and shotgun sequencing. Fatty acids (FAs) were measured by gas chromatography, while immune factors were determined by enzyme-linked immunosorbent assay and Luminex technology. RESULTS: A specific pattern of microbiota in the gut of CM FPIES patients was found, characterized by a high abundance of enterobacteria. Also, an intense excretion of FAs in the feces of these infants was observed. Furthermore, correlations were found between fecal bifidobacteria and immune factors. CONCLUSION: These fecal determinations may be useful to gain insight into the pathophysiology of this syndrome and should be taken in consideration for future studies of FPIES patients.