Production Of Short-chain Fatty Acids Research Articles

The gut microbiota as an early predictor of COVID-19 severity.

Several studies reported alterations of the human gut microbiota (GM) during COVID-19. To evaluate the potential role of the GM as an early predictor of COVID-19 at disease onset, we analyzed gut microbial samples of 315 COVID-19 patients that differed in disease severity. We observed significant variations in microbial diversity and composition associated with increasing disease severity, as the reduction of short-chain fatty acid producers such as Faecalibacterium and Ruminococcus, and the growth of pathobionts as Anaerococcus and Campylobacter. Notably, we developed a multi-class machine-learning classifier, specifically a convolutional neural network, which achieved an 81.5% accuracy rate in predicting COVID-19 severity based on GM composition at disease onset. This achievement highlights its potential as a valuable early biomarker during the first week of infection. These findings offer promising insights into the intricate relationship between GM and COVID-19, providing a potential tool for optimizing patient triage and streamlining healthcare during the pandemic.IMPORTANCEEfficient patient triage for COVID-19 is vital to manage healthcare resources effectively. This study underscores the potential of gut microbiota (GM) composition as an early biomarker for COVID-19 severity. By analyzing GM samples from 315 patients, significant correlations between microbial diversity and disease severity were observed. Notably, a convolutional neural network classifier was developed, achieving an 81.5% accuracy in predicting disease severity based on GM composition at disease onset. These findings suggest that GM profiling could enhance early triage processes, offering a novel approach to optimizing patient management during the pandemic.

Genomic analysis and functional properties of Lactobacillus johnsonii GJ231 isolated from healthy beagles.

Probiotics are one of the management tools to improve the host's healthy microbiota. The positive effects of probiotics on host health are species-specific, so probiotics isolated from host's own gut may be most beneficial. Many of the metabolites (e.g., short-chain fatty acids, bacteriocins, and hydrogen peroxide) produced by Lactobacillus johnsonii have specific inhibitory profiles against invading pathogens. In this study, we isolated L. johnsonii GJ231 from the intestinal tract of healthy female beagles. The genome size of 1.763 M encoded a total of 1,691 predicted genes. Many carbohydrate-active enzymes responsible for carbohydrate degradation and the production of short-chain fatty acids were also predicted. The metabolic profile of short-chain fatty acids in L. johnsonii GJ231 was determined using LC-MS/MS. The bacteriocin-producing gene bacteriocin (lactacin F) in L. johnsonii GJ231 was also predicted. In vitro, experiments demonstrated that GJ231 can thrive in weak acids, 0.3% bile salts, and artificial gastrointestinal fluid models. It was tolerant of to high temperatures up to 70°C, was non- hemolytic, inhibited pathogenic bacteria, and had a high antioxidant capacity. In vivo safety experiments conducted in mice revealed that oral administration of GJ231 not only had no toxic side effect but also increased their antioxidant capacity. In conclusion, combining the above test results, which collectively demonstrate that canine-derived L. johnsonii GJ231 was a non-pathogenic, acid-tolerant and bile-salt-tolerant probiotic strain that inhibits pathogenic bacteria and improves host antioxidant function. This may make it a promising candidate for the development of innovative functional foods for pets.

The Gut Microbiota characterization of a World-Class Mountain Trail runner during a complete competition season: a case report.

In the present case study, the gut microbiota (GM) profile of a male Elite Mountain Runner (34 years, 171cm, 59 kg, VO2max: 92 mL·min-1 ·kg-1) was analyzed over 5 months competitive period (6 samples). The GM diversity increased through the season coinciding higher levels to the peak performance and shorter and longer race (42 vs. 172 km) produced different phenotypic GM changes. Shorter race promoted the elevation of protective bacteria related to positive benefits (higher production of short-chain fatty acids (SCFAs), lactate resynthesis, mucin degraders). In contrast, longer race promoted an elevation of opportunistic pathogenic bacteria while reducing protective commensal bacteria. The present findings indicate that a higher resilience of the GM after competitions may support rapid recovery from maximal exercise. The GM analyses pre- and post-competition could represent a rapid indicator for the (patho)physiological impact of exercise and provide information on gut health and recovery time needed.

The Effect of Dietary Types on Gut Microbiota Composition and Development of Non-Communicable Diseases: A Narrative Review.

The importance of diet in shaping the gut microbiota is well established and may help improve an individual's overall health. Many other factors, such as genetics, age, exercise, antibiotic therapy, or tobacco use, also play a role in influencing gut microbiota. This narrative review summarizes how three distinct dietary types (plant-based, Mediterranean, and Western) affect the composition of gut microbiota and the development of non-communicable diseases (NCDs). A comprehensive literature search was conducted using the PubMed, Web of Science, and Scopus databases, focusing on the keywords "dietary pattern", "gut microbiota" and "dysbiosis". Both plant-based and Mediterranean diets have been shown to promote the production of beneficial bacterial metabolites, such as short-chain fatty acids (SCFAs), while simultaneously lowering concentrations of trimethylamine-N-oxide (TMAO), a molecule associated with negative health outcomes. Additionally, they have a positive impact on microbial diversity and therefore are generally considered healthy dietary types. On the other hand, the Western diet is a typical example of an unhealthy nutritional approach leading to an overgrowth of pathogenic bacteria, where TMAO levels rise and SCFA production drops due to gut dysbiosis. The current scientific literature consistently highlights the superiority of plant-based and Mediterranean dietary types over the Western diet in promoting gut health and preventing NCDs. Understanding the influence of diet on gut microbiota modulation may pave the way for novel therapeutic strategies.

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 β-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.

Bioactive potential of unpurified hydrothermal xylooligosaccharides: Implications for prebiotic formulations from sugarcane bagasse

This study explored the bioactive potential of xylooligosaccharides (XOS) obtained from sugarcane bagasse through one-step hydrothermal process approach, applied here without the typical purification or further processing steps commonly required to produce XOS for use as prebiotic. We investigated various processing conditions to optimize the yield and biofunctional properties of these unpurified, hydrothermally produced XOS-rich hemicellulose hydrolysates from sugarcane bagasse. The prebiotic efficacy of these unpurified XOS-rich hydrolysates was evaluated by their ability to support the metabolism of bifidobacteria in anaerobic fermentation. The results revealed that the chain length of XOS significantly influenced their effectiveness as a carbon source, with longer chains (beyond hexoses) being less efficient. Despite the presence of lignin and sugar degradation by-products, generally considered detrimental in such processes, they did not negatively affect bifidobacteria growth. In addition, variations in the degree of acetyl substitutions on the XOS mildly influenced the production of short-chain fatty acids. Importantly, unpurified XOS-rich hydrolysates produced under selected hydrothermal conditions demonstrated bioactive performance that was comparable to, or even superior to, commercial prebiotics. These findings confirm the practical viability of using unpurified, hydrothermally derived XOS-rich hydrolysates from sugarcane bagasse as prebiotics, emphasizing the innovative approach of eliminating purification and additional processing, thereby simplifying the production process while still maintaining high prebiotic efficacy.

Fibroblast growth factor 21 improves insulin sensitivity by modulating the bile acid-gut microbiota axis in type Ⅱ diabetic mice

BackgroundFibroblast growth factor 21 (FGF21) is an important regulator of glycolipid metabolism. However, whether the gut microbiota is related to the anti-diabetic and obesity effects of FGF21 remains unclear. MethodsOur research used KO/KO db/db male mice and streptozotocin (STZ)-induced to simulate the construction of two type II diabetic mellitus (T2DM) models, and detected impaired glucose tolerance in the model by using the ipGTT and ITT assays, and collected feces from the model mice for sequencing of the intestinal flora and the content of short-chain fatty acids. H＆E staining was used to detect changes in intestinal tissue, the serum levels of LPS and GLP-1 were detected by ELISA. ResultsIn this study, we found that FGF21 significantly improved insulin sensitivity, attenuated intestinal lesions, and decreased serum lipopolysaccharide (LPS) concentrations in T2DM mice. Moreover, FGF21 reshaped the gut microbiota and altered their metabolic pathways in T2DM mice, promoting the production of short-chain fatty acids (SCFAs) and the secretion of glucagon-like peptide 1 (GLP-1). Fecal transplantation experiments further confirmed that feces from FGF21-treated diabetic mice demonstrated similar effects as FGF21 in terms of anti-diabetic activity and regulation of gut microbiota dysbiosis. Additionally, the antibiotic depletion of gut microbiota abolished the beneficial effects of FGF21, including increased GLP-1 secretion and fecal SCFA concentration. Additionally, the FGF21 effects of ameliorating intestinal damage and suppressing plasma LPS secretion were suppressed. All these findings suggest that FGF21 prevents intestinal lesions by modifying the gut microbiota composition. Furthermore, FGF21 affected bile acid synthesis by inhibiting CYP7A1, the key enzyme of bile acid synthesis. ConclussionTherefore, FGF21 enriched beneficial bacteria by preventing bile acid synthesis and stimulating the secretion of the intestinal hormone GLP-1 via the increased production of gut microbiota metabolites, thereby exerting its anti-diabetic effects.

PSXII-21 How does the inclusion of dried distillers grains plus soluble affect short-chain fatty acid and methane production in feedlot diets?

Abstract The inclusion of the coproduct dry distillers grains plus soluble (DDGS) in the diet of finishing cattle can lead to changes in the nutritional profile of the diets, causing an increase in protein content and a reduction in starch. It is necessary to understand how changes in rumen substrates affect rumen metabolic activity, acids, and enteric methane (CH4) production. Five treatments were used, considering levels of DDGS inclusion in the dry matter (DM) of 1) 0 g/kg of DDGS, 2) 150 g/kg of DDGS, 3) 300 g/kg of DDGS, 4) 450 g/kg DDGS, or 5) 600 g/kg DDGS in finishing diets. The metabolism experiment was conducted with rumen-cannulated Nellore bulls (n = 20) with initial body weight (BW) of 401.8 ± 27.0 kg. The production of short-chain fatty acids (SCFA) and CH4 were determined using the ex-situ ruminal fermentation technique. Rumen content was manually collected from 0, 4, 8 and 12 h post-feeding. The liquid and solid fractions of rumen content were used in four 50 mL penicillin-type flasks per animal. Of the four flasks prepared, two are called “blank” and inactivated in boiling water to stop fermentation, and the other two (microrumen) are incubated in a thermostatic bath, simulating the conditions existing in the rumen of animals (presence of microorganisms, anaerobes, temperature of 39ºC, natural animal saliva, physiological pH) for 30 min. After 30 min, incubated flasks were also inactivated in boiling water to stop fermentation. Subsequently, measurements of the final products of rumen fermentation (SCFA and CH4) were carried out in each bottle. Total rumen emptying was performed to determine the rumen pool of DM. The data will be analyzed in the SAS software, the mean of the treatments will be compared using test of mean and orthogonal contrasts. The declared significance is P ≤ 0.05. The inclusion or levels of DDGS did not affect CH4 production of gּ kg DM-1ּ d-1 and gּ kg DM-1ּ d-1 (P > 0.05). There was an effect of the treatments on the production of propionate (gּ kg DM-1ּ d-1; P = 0.0448), with a decreasing linear effect (P = 0.0087) with the increase in the inclusion of DDGS in diet (0; 150; 300; 450; 600 g/kg of DDGS; means 137.20; 160.32; 117.60; 87.09; 91.52 gּ kg DM-1ּ d-1 propionate, respectively). There was no effect of DDGS levels on the production of Acetate, Butyrate, or total SCFAs (gּ kg DM-1ּ d-1). In summary, DDGS inclusion affects rumen metabolic activity, decreasing propionate production, but does not affect the production of other SCFAs nor CH4 production.

Improvement of heat treated spirulina proteins and their enzymatic hydrolysates on osteoporosis under simulated microgravity

In the space microgravity environment, bone loss poses a formidable health challenge for astronauts. Dietary intake of renewable food components offers a feasible approach to mitigate bone loss associated with primary osteoporosis, aligning with the demands of long-term space missions. Recent research has highlighted the potential of Spirulina in ameliorating osteoporosis, with thermal processing enhancing the protein bioavailability. This study investigates the effects of different heat-treated Spirulina proteins (SPP) and their enzymatic hydrolysates on osteoporosis using a hindlimb suspension model (HLS) in mice to simulate microgravity conditions. The results demonstrate that heat-treated SPP and enzymatic hydrolysates significantly preserve skeletal morphology, suppress bone resorption, and enhance bone density, with the microwave-treated SPP hydrolysate (MWSPPH) showing the most pronounced improvement effects. Mechanistic insights reveal that MWSPPH enhances bone health by modulating the FoxO/Wnt/β-catenin signaling pathway. Specifically, MWSPPH reduces the expression of FoxO and facilitates the accumulation of β-catenin, while also indirectly modulating osteoclast-related signaling by altering RANKL and RANK expression. It also beneficially increases beneficial gut microbiota and the production of short-chain fatty acids, thereby improving bone density, suggesting its potential as a dietary strategy for managing osteoporosis in space environments.

Lactic Acid Bacterial Fermentation of Esterified Agave Fructans in Simulated Physicochemical Colon Conditions for Local Delivery of Encapsulated Drugs

Understanding drug release in the colon is fundamental to developing efficient treatments for colon-related diseases, while unraveling the relationship between the colonic microbiota and excipients is crucial to unveiling the effect of biomaterials on the release of drugs. In this contribution, the bio-release of ibuprofen (encapsulated in acetylated and palmitoylated agave fructans) was evaluated by fermentation with lactic acid bacteria in simulated physicochemical (pH and temperature) colon conditions. It was observed that the size of the acyl chain (1 in acetyl and 15 in palmitoyl) was critical both in the growth of the microorganisms and in the release of the drug. For example, both the bacterial growth and the release of ibuprofen were more favored with acetylated fructan microspheres. Among the microorganisms evaluated, Bifidobacterium adolescentis and Lactobacillus brevis showed great potential as probiotics useful to release drugs from modified fructans. The production of short-chain fatty acids (lactic, acetic, and propionic acids) in the course of fermentations was also determined, since such molecules have a positive effect both on colon-related diseases and on the regulation of the intestinal microbiota. It was found that a higher concentration of acetate is related to a lower growth of bacteria and less release of ibuprofen.

Substitutive Effects of Milk vs. Vegetable Milk on the Human Gut Microbiota and Implications for Human Health.

Background: In the last two decades, the consumption of plant-based dairy substitutes in place of animal-based milk has increased in different geographic regions of the world. Dairy substitutes of vegetable origin have a quantitative composition of macronutrients such as animal milk, although the composition of carbohydrates, proteins and fats, as well as bioactive components, is completely different from that of animal milk. Many milk components have been shown to have relevant effects on the intestinal microbiota. Methods: Therefore, the aim of this review is to compare the effects obtained by previous works on the composition of the gut microbiota after the ingestion of animal milk and/or vegetable beverages. Results: In general, the results obtained in the included studies were very positive for animal milk intake. Thus, we found an increase in gut microbiota richness and diversity, increase in the production of short-chain fatty acids, and beneficial microbes such as Bifidobacterium, lactobacilli, Akkermansia, Lachnospiraceae or Blautia. In other cases, we found a significant decrease in potential harmful bacteria such as Proteobacteria, Erysipelotrichaceae, Desulfovibrionaceae or Clostridium perfingens after animal-origin milk intake. Vegetable beverages have also generally produced positive results in the gut microbiota such as the increase in the relative presence of lactobacilli, Bifidobacterium or Blautia. However, we also found some potential negative results, such as increases in the presence of potential pathogens such as Enterobacteriaceae, Salmonella and Fusobacterium. Conclusions: From the perspective of their effects on the intestinal microbiota, milks of animal origin appear to be more beneficial for human health than their vegetable substitutes. These different effects on the intestinal microbiota should be considered in those cases where the replacement of animal milks by vegetable substitutes is recommended.

PSXII-16 Effect of including sugar cane molasses on rumen fermentation characteristics in young beef finishing heifers

Abstract In ruminant animals, the use of molasses has benefits related to improved voluntary intake and increased production of short-chain fatty acids (SCFA) in the rumen, especially butyrate. Butyrate is closely related to gastrointestinal tract health, as it may contribute to the increase in the absorption area of the ruminal epithelium and improve the utilization of diet components, resulting in improved voluntary intake and immune response capacity in stressful situations, such as weaning. Hence, our objective was to assess the effect of sugar cane molasses on rumen fermentation characteristics in young beef finishing heifers. Newly weaned Nellore × Red Angus heifers (n = 12) averaging 238 ± 5.1 kg body weight (BW), were used. All heifers were housed in individual pens with concrete floors, covered feeders, and drinkers. The basal diet was 50 % concentrate, and consisted of corn silage, sorghum silage, ground corn, soybean meal, urea, and a mineral premix. The diet was provided twice daily at 0700 and 1600 h, allowing up to 10% in orts (as fed). The following treatments were evaluated: control (no addition of powdered molasses) or addition of 50 g/kg of diet [dry matter (DM) basis] of powdered molasses. The experiment lasted for a total of 80 d, including a 14-d adaptation period. On d 68 and 76, rumen fluid samples were collected both before and 4 h after the morning feeding using an oral probe coupled to a vacuum pump. The initial fluid samples were discarded to prevent saliva contamination. The rumen fluid was filtered through four layers of cheesecloth, and then pH was measured. Subsequently, samples were taken and stored in an ultra-freezer (-80°C) for subsequent SCFA analysis. The data were subjected to analysis of variance using the GLM procedure of SAS 9.4 (α = 0.05). Providing molasses increased ruminal pH compared with control heifers (P < 0.032). Adding molasses did not affect SCFA concentration (P > 0.90). Conversely, we detected an effect of molasses on SCFA molar proportion. The molar proportion of both acetate (P < 0.013) and butyrate (P < 0.012) were greater in heifers fed molasses than with controls. On the other hand, dietary molasses addition decreased (P < 0.001). the propionate molar proportion. This resulted in an increased (P < 0.002) acetate-to-propionate ratio in heifers fed diets containing molasses. In conclusion, providing sugar cane molasses enhances rumen fermentation characteristics in young beef finishing heifers.

30 Microbiota and Companion Animal Health

Abstract The intestinal microbiota has been shown to have an important role in health and disease of animals. It is a complex system that depends on interactions between the luminal environment and specific bacterial taxa and their function (e.g., production of short-chain fatty acids, conversion of bile acids). Dietary substrates are an important factor for microbial metabolism and supplements have the potential to help in maintaining intestinal health. Major changes in the microbiota and their loss of function (dysbiosis) are mainly associated with antibiotic treatment and in chronic intestinal disease likely due to chronic remodeling of the epithelium. Therefore, often these changes persist long-term. Chronic enteropathies (CE) occur very commonly in dogs and cats, and are frustrating to treat due to lack of specific markers. The pathophysiology is complex and includes changes in the immune system (e.g., inflammation), intestinal function, and the intestinal microbiome. The current classification based on treatment response (i.e., food- vs. steroid-responsive) is currently being questioned, as new research findings indicate that CE is a syndrome with many overlapping unspecific features, often with chronic irreversible changes in intestinal function and dysbiosis. The presentation will summarize novel research about the pathophysiology and novel concepts in multi-modal therapy to these conditions. This program will help better understand the role of the intestinal microbiota in health and disease (with focus on acute diarrhea and chronic intestinal inflammation). New diagnostic methods for evaluation of the intestinal microbiota will be covered. Finally, this lecture will review how to best manage the clinical signs of acute and chronic diarrhea. This includes new evidence of the negative impact of antibiotics on the microbiome and the critical role nutrition can play in managing these patients.

Effects of in vitro simulated digestion and fecal fermentation on the structure and regulating the glucose and lipid activity of a polysaccharide from Mori Folium

Mori folium, as a homologous drug-food, has hypoglycemic and lipid-lowering activity. Polysaccharides are the main bioactive ingredient of the Mori folium that exhibit diverse biological activities. In this study, a homogeneous polysaccharide (MP4) was purified and characterized from Mori folium. The changes of MP4 affected by saliva, simulated gastrointestinal juice, and human fecal fermentation, including physicochemical property or its bioactivity, were systematically investigated. Meanwhile, the influence of fermentation on the bioactivity were evaluated. The results showed that the backbone of MP4 is mainly composed of →4)-α-D-GalpA-(1→ residues. The molecular weight, the levels of reducing sugar content and free monosaccharides of MP4 exhibited no significant differences indicating that gastrointestinal digestion has a minimal effect on the physicochemical characteristics of MP4. However, during in vitro gut microbiota fermentation, MP4 are significantly degraded and utilized by gut microbiota, showing increased the production of short-chain fatty acids, notably acetic acid and propionic acid. The relative abundance of beneficial bacteria such as Bacteroidetes and Actinobacteria were significantly increased, whereas the levels of pathogenic bacteria such as Fusobacteria and Megamonas were significantly decreased, which changed the composition of the gut microbiota. The Firmicutes/Bacteroides ratio was also decreased significantly. Interestingly, after in vitro fermentation, the α-glucosidase inhibitory activity was increased, the lipase inhibitory activity and cholesterol adsorption activity was decreased. Correlation analysis showed that the relative abundance of some bacteria was significantly correlated with the bioactivities. These results provide a basis for the development of Mori folium polysaccharides as functional probiotic products.

Distinct prebiotic effects of polysaccharide fractions from Polygonatum kingianum on gut microbiota

This study investigated the physicochemical properties, digestive stability, and in vitro fermentation behavior of Polygonatum kingianum polysaccharide (PKP) fractions (PKP60, PKP70, PKP80) obtained through graded ethanol precipitation. High-performance gel permeation chromatography revealed significant molecular weight differences among the fractions, while reverse-phase high-performance liquid chromatography indicated consistent monosaccharide types with variations in their proportions. Uronic acid analysis confirmed that all polysaccharide fractions met the criteria for neutral polysaccharides. Congo red staining confirmed the presence of a triple-helix structure in all PKP fractions. Comprehensive analysis demonstrated that these fractions remained stable during in vitro digestion, as evidenced by consistent molecular weights and total carbohydrate content, with no significant production of free monosaccharides or reducing sugars. All PKP fractions were fermented by gut microbiota, resulting in the production of short-chain fatty acids. Beta diversity and structural analyses of gut microbiota revealed distinct modulatory effects associated with each PKP fraction. The PKP fractions promoted probiotic growth, especially PKP70, which significantly enhanced Bifidobacterium proliferation, indicating strong prebiotic potential. These findings underscore the importance of isolation and purification methods in determining the functionality and gut microbiota-modulating effects of plant-derived polysaccharides, emphasizing the need for in-depth research that extends beyond merely evaluating their source.

Metformin modulates microbiota and improves blood pressure and cardiac remodeling in a rat model of hypertension.

Metformin has been attributed to cardiovascular protection even in the absence of diabetes. Recent observations suggest that metformin influences the gut microbiome. We aimed to investigate the influence of metformin on the gut microbiota and hypertensive target organ damage in hypertensive rats. Male double transgenic rats overexpressing the human renin and angiotensinogen genes (dTGR), a model of angiotensin II-dependent hypertension, were treated with metformin (300 mg/kg/day) or vehicle from 4 to 7 weeks of age. We assessed gut microbiome composition and function using shotgun metagenomic sequencing and measured blood pressure via radiotelemetry. Cardiac and renal organ damage and inflammation were evaluated by echocardiography, histology, and flow cytometry. Metformin treatment increased the production of short-chain fatty acids (SCFA) acetate and propionate in feces without altering microbial composition and diversity. It significantly reduced systolic and diastolic blood pressure and improved cardiac function, as measured by end-diastolic volume, E/A, and stroke volume despite increased cardiac hypertrophy. Metformin reduced cardiac inflammation by lowering macrophage infiltration and shifting macrophage subpopulations towards a less inflammatory phenotype. The observed improvements in blood pressure, cardiac function, and inflammation correlated with fecal SCFA levels in dTGR. Invitro, acetate and propionate altered M1-like gene expression in macrophages, reinforcing anti-inflammatory effects. Metformin did not affect hypertensive renal damage or microvascular structure. Metformin modulated the gut microbiome, increased SCFA production, and ameliorated blood pressure and cardiac remodeling in dTGR. Our findings confirm the protective effects of metformin in the absence of diabetes, highlighting SCFA as a potential mediators.

Lactiplantibacillus argentoratensis AGMB00912 protects weaning mice from ETEC infection and enhances gut health.

Maintaining a healthy intestinal environment, optimal epithelial barrier integrity, and balanced gut microbiota composition are essential for the growth performance of weaning pigs. We identified Lactiplantibacillus argentoratensis AGMB00912 (LA) in healthy porcine feces as having antimicrobial activity against pathogens and enhanced short-chain fatty acid (SCFA) production. Herein, we assess the protective role of LA using a weaning mouse model with enterotoxigenic Escherichia coli (ETEC) infection. LA treatment improves feed intake and weight gain and alleviates colon shortening. Furthermore, LA inhibits intestinal damage, increases the small intestine villus height compared with the ETEC group, and enhances SCFA production. Using the Kyoto Encyclopedia of Genes and Genomes and other bioinformatic tools, including InterProScan and COGNIZER, we validated the presence of SCFA-producing pathways of LA and Lactiplantibacillus after whole genome sequencing. LA mitigates ETEC-induced shifts in the gut microbiota, decreasing the proportion of Escherichia and Enterococcus and increasing SCFA-producing bacteria, including Kineothrix, Lachnoclostridium, Roseuburia, Lacrimispora, Jutongia, and Blautia. Metabolic functional prediction analysis revealed enhanced functions linked to carbohydrate, amino acid, and vitamin biosynthesis, along with decreased functions associated with infectious bacterial diseases compared to the ETEC group. LA mitigates the adverse effects of ETEC infection in weaning mice, enhances growth performance and intestinal integrity, rebalances gut microbiota, and promotes beneficial metabolic functions. These findings validate the functionality of LA in a small animal model, supporting its potential application in improving the health and growth performance of weaning pigs.

Physicochemical properties, structure and regulatory effect on gut microbiota of dietary fiber extracted from soybean meal via dry fractionation

Currently, dry fractionation is employed to extract dietary fiber (DF) from food processing bypuroduct owing to its advantages of low energy and eco-friendly. Procedures of dry fractionation mainly include milling and air classification. Soybean meal (SBM) is a processing byproduct rich in DF. Few studies have used dry fractionation to extract SBM dietary fiber (SMF), and the physicochemical properties, structural characteristics, and activity of SMF extracted via dry fractionation remain unclear. Herein, SMF was prepared via dry fractionation and results showed that compared with that of SBM without pores and high crystallinity, SMF had loose and porous surface and low crystallinity. Moreover, the water holding capacity, oil holding capacity and swelling ability of SMF were significantly higher than SBM. After 24 h of in vitro fecal fermentation, the SMF group produced abundant short chain fatty acids (SCFA) such as acetic, propionic, and butyric acids and the total SCFA production was substantially higher than that in the inulin (INL) group. SMF also promoted the relative abundance of beneficial bacteria such as Prevotella, Dialister, and Bifidobacterium and reduced the relative abundance of harmful bacteria such as Escherichia–Shigella. In conclusion, SMF extracted via dry fractionation can significantly alter the relative abundance and diversity of gut microbiota and promote the production of SCFA, which is conducive to the regulation of the human gut microbiota. This study can provide insights into the preparation of DF via dry fractionation and provide theoretical basis for SMF to be used as a prebiotic.

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.

The Effects of Single- or Mixed-Strain Fermentation of Red Bean Sourdough, with or without Wheat Bran, on Bread Making Performance and Its Potential Health Benefits in Mice Model.

The effects of single- (Lactobacillus fermentum) or mixed-strain (Lactobacillus fermentum, Kluyveromyces marxianus) fermentation of red bean with or without wheat bran on sourdough bread quality and nutritional aspects were investigated. The results showed that, compared to unfermented controls, the tannins, phytic acid, and trypsin inhibitor levels were significantly reduced, whereas the phytochemical (TPC, TFC, and gallic acid) and soluble dietary fiber were increased in sourdough. Meanwhile, more outstanding changes were obtained in sourdough following a mixed-strain than single-strain fermentation, which might be associated with its corresponding β-glucosidase, feruloyl esterase, and phytase activities. An increased specific volume, reduced crumb firmness, and greater sensory evaluation of bread was achieved after mixed-strain fermentation. Moreover, diets containing sourdough, especially those prepared with mixed-strain-fermented red bean with wheat bran, significantly decreased serum pro-inflammatory cytokines levels, and improved the lipid profile, HDL/LDL ratio, glucose tolerance, and insulin sensitivity of mice. Moreover, gut microbiota diversity increased towards beneficial genera (e.g., Bifidobacterium), accompanied with a greater increase in short-chain fatty acid production in mice fed on sourdough-based bread diets compared to their controls and white bread. In conclusion, mixed-strain fermentation's synergistic effect on high fiber-legume substrate improved the baking, sensory quality, and prebiotic effect of bread, leading to potential health benefits in mice.