Fecal Short-chain Fatty Acid Concentrations Research Articles

Whole-Genome Metagenomic Analysis of Functional Profiles in the Fecal Microbiome of Farmed Sows with Different Reproductive Performances

Recent studies suggested an association between the reproductive performance of sows and their gut microbiota. To understand how the gut microbiota affect the reproductive performances of sows, we conducted a whole-genome metagenomic analysis on the fecal microbial functional profiles of sows with high and low reproductive performances. We used 60 sows from six farms (10 sows/farm), including 30 sows from three farms with higher reproductive performances (the mean number of weaned piglets/sow/year) (group H) and 30 sows from three farms with lower performances (group L). Fecal microbial DNA was subjected to a whole-genome metagenomic analysis. Biomarker exploration analysis identified “carbohydrate transport and metabolism” as the most discriminative function enriched in group H. Further analysis of carbohydrate-active enzymes revealed that the fecal microbiome of group H had a greater capacity to degrade dietary fiber, specifically cellulose and pectin. Group H also exhibited higher fecal short-chain fatty acid (SCFA) concentrations than group L, with the abundances of cellulose- and pectin-degrading genes showing significant positive correlations with fecal SCFA concentrations. Taxonomic analysis indicated greater contributions of Prevotella, Treponema, Ruminococcus, and Fibrobacter to cellulose and pectin degradation in the fecal microbiome in group H. In conclusion, higher reproductive performances of sows were, at least in part, associated with a greater microbial capacity for degrading cellulose and pectin, resulting in a higher SCFA production in the hindgut.

Effectiveness and safety study of formula containing probiotics, prebiotics, synbiotics on fullterm infants' growth - a systematic review and meta-analysis of randomized controlled study.

Probiotics, prebiotics, and synbiotics, are hot topics of research and have been shown to improve the body's disease state and promote health. Analysis of whether infant formula containing probiotcs, prebiotics, synbiotics is beneficial to infant and child growth. We systematically searched multiple electronic databases (PubMed, Web of Science, The Cochrane Library, Embase) to identify eligible studies published from 1966 to December 25, 2022. Included studies were randomized controlled trials (RCTs) studying the influence of milk powder containing probiotcs, prebiotics, synbiotics on infants and children's growth. RevMan 5.4 was used to analyze the data. A total of 55 RCTs with a total sample size of 8868 participants met the inclusion criteria. Milk powder with probiotics, prebiotics, synbiotics does not significantly improve the growth of infants and children (Weight, height, BMI, and Head Circumference); The incidence of minor adverse events (OR 0.88, 95% CI 0.70-1.11 P = 0.28) and serious adverse events (OR 0.92, 95% CI 0.62-1.36 P = 0.67) was also comparable to the control group; The intestinal microbial diversity of infants consuming probiotcs, prebiotics, synbiotics supplemented formula was lower than that of infants consuming formula without probiotcs, prebiotics, synbiotics (SMD -0.88, 95% CI -1.66- -0.1 P = 0.03), but the abundance of individual beneficial flora was increased. (SMD 1.62, 95%CI 0.61-2.62 P = 0.002). In particular, the abundance of Lactobacillus (SMD 1.62, 95% CI 0.61-2.62 P = 0.002). For metabolites, synbiotics increased fecal antibody concentrations (SMD 0.47, 95% CI 0.08-0.86 P = 0.02), but fecal short-chain fatty acid concentrations remained balanced in both groups (SMD 0.05 95% CI -0.17-0.28 P = 0.64). Compared to the control group, infants who consumed formula with prebiotics had softer stools (SMD -1.47, 95% CI -2.23 to -0.7 P = 0.002) and lower stool pH (SMD -0.82, 95% CI -1.15- -0.5 P < 0.00001), there is also more frequency of bowel movements (SMD 0.27, 95% CI 0.09-0.44 P = 0.002). Probiotcs, prebiotics, synbiotics supplemented formulas significantly increased abundance of individual probiotics, alter intestinal antibody secretion, and improve bowel movements. Incidence of adverse reactions did not differ between the two groups. So we can choose formula-supplemented probiotcs, prebiotics, synbiotics to maintain the intestinal health of infants.

Effects of single-dose ruminal infusions of high or low short-chain fatty acid concentrations and high or low pH on apparent total tract digestibility and hindgut fermentation of pre-weaned dairy calves

While the importance of pH and short-chain fatty acids (SCFA) on rumen development are well-known, their impact on the small and large intestine are unclear. This study investigated how single-dose ruminal infusions with high or low short-chain fatty acid concentrations and high or low pH affect calves' productivity as well as physiological parameters associated with hindgut acidosis at 3-time points in 49 d. Holstein bull calves (n = 32) were individually housed and fed milk replacer (900 g/d) twice daily and calf starter and water ad libitum. At d 10 ± 3 of life, the rumens were fistulated and cannulated. At d 14 of life, calves were grouped by body weight and assigned in a 2 × 2 factorial arrangement of treatments: high or low SCFA concentration (285 vs. 10 mM) and high or low pH (6.2 vs. 5.2), creating 4 treatment groups: high SCFA concentration, high pH (HS-HP); high SCFA concentration, low pH (HS-LP); low SCFA concentration, high pH (LS-HP); and low SCFA concentration, low pH (LS-LP). On d 21, 35, 49, feces were sampled to calculate apparent total-tract digestibility, determinate organic acid concentrations (i.e., SCFA, BCFA and lactic acid), and pH. Afterward, the rumen was evacuated and underwent a single-dose infusion for 4 h with one of 4 treatment buffers. After completion of rumen infusion on d 49, calves were harvested, and the tissue weight and length, and digesta pH of the rumen, cecum, colon, and rectum were recorded along with the digesta pH of duodenum, jejunum, and ileum only at d 49 after dissection. Data were analyzed with main factors as fixed effects and repeated measures for weekly measurements. Treatments did not affect performance parameters such as feed intake, ADG, apparent total-tract digestibility and gut measurements. In the duodenum, jejunum, and ileum, HS-HP had a greater digesta pH than LS-HP, while the hindgut digesta pH was only affected by the SCFA concentration. High SCFA concentration increased the concentration of colonic isovaleric acid and fecal BCFA, while only colonic acetic acid and fecal lactic acid concentrations were affected by treatment. Fecal SCFA and BCFA concentrations increased mainly on d 35. In summary, 4 h of physiological buffer infusion in the rumen does not change apparent total-tract digestibility and gut measurements but does affect hindgut fermentation parameters (i.e., organic acid concentrations and digesta pH). In addition, calves can experience increased risks of hindgut acidosis around 35 d of life.

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.

PSIX-11 Effects of black soldier fly larvae on the serum chemistry, hematology, fecal characteristics, and oral health measures of healthy adult cats

Abstract Black soldier fly larvae (BSFL) serve as an alternative protein source for pet food products. Even though BSFL are one of many insect species being added to dog foods and treats, knowledge of its effects in cats remains limited. Further investigations are imperative to delineate the effects of BSFL-based ingredients in cats. Therefore, the objective of this study was to determine the effects of BSFL on serum chemistry, hematology, fecal characteristics, and oral health measures of adult cats. All procedures were approved by the University of Illinois IACUC prior to experimentation. Adult cats [n = 25; 17 females, 8 males; 6.28 ± 0.27 yr of age; 4.50 ± 0.18 kg body weight (BW)] were used in a completely randomized design. The study was composed of a 21-d baseline phase and a 70-d experimental phase. During the baseline phase, all cats were fed a control diet based on chicken meal (35% of diet). After baseline, cats were randomly assigned to 1 of 2 experimental diets: control diet (n = 12) or BSFL-containing diet (20% whole BSFL meal and 24% chicken meal; n = 13). At baseline, teeth were cleaned by a veterinary dentist. Breath samples were analyzed for volatile sulfur compounds (VSC), salivary pH was measured, and blood samples were collected for serum chemistry and hematology at baseline and after 35 d and 70 d on treatment. At baseline and after 70 d on treatment, fecal samples were scored and collected for pH, dry matter, and metabolite measurement. Gingivitis, plaque, and calculus scores were performed by a veterinary dentist after 70 d on treatment. All data were analyzed using the Mixed Models procedure of SAS. Diet, time, and diet*time interaction effects were tested, with P &amp;lt; 0.05 being considered significant. Over time, VSC increased (P &amp;lt; 0.0001) in all cats, but was unaffected by diet. Diet*time interactions were observed for fecal pH, fecal scores, and blood cholesterol and triglyceride concentrations. Blood cholesterol concentrations increased (P &amp;lt; 0.05) over time in cats fed the control diet, but remained stable in cats fed the BSFL diet. The opposite effect was observed with blood triglycerides. Triglyceride concentrations increased (P &amp;lt; 0.05) in cats fed the BSFL diet over time, but were stable in cats fed the control diet. Cats consuming BSFL had reduced (P &amp;lt; 0.05) fecal pH, dry matter content, and protein catabolite concentrations, but increased (P &amp;lt; 0.05) fecal short-chain fatty acid concentrations and fecal scores. Overall, 20% BSFL dietary inclusion had comparable effects as chicken meal, suggesting that it will serve as a suitable replacement in cat foods.

Gut microbiome signatures associated with type 2 diabetes in obesity in Mongolia.

Mongolian people possess a unique dietary habit characterized by high consumption of meat and dairy products and fewer vegetables, resulting in the highest obesity rate in East Asia. Although obesity is a known cause of type 2 diabetes (T2D), the T2D rate is moderate in this population; this is known as the "Mongolian paradox." Since the gut microbiota plays a key role in energy and metabolic homeostasis as an interface between food and body, we investigated gut microbial factors involved in the prevention of the co-occurrence of T2D with obesity in Mongolians. We compared the gut microbiome and metabolome of Mongolian adults with obesity with T2D (DO: n = 31) or without T2D (NDO: n = 35). Dysbiotic signatures were found in the gut microbiome of the DO group; lower levels of Faecalibacterium and Anaerostipes which are known as short-chain fatty acid (SCFA) producers and higher levels of Methanobrevibacter, Desulfovibrio, and Solobacterium which are known to be associated with certain diseases. On the other hand, the NDO group exhibited a higher level of fecal SCFA concentration, particularly acetate. This is consistent with the results of the whole shotgun metagenomic analysis, which revealed a higher relative abundance of SCFA biosynthesis-related genes encoded largely by Anaerostipes hadrus in the NDO group. Multiple logistic regression analysis including host demographic parameters indicated that acetate had the highest negative contribution to the onset of T2D. These findings suggest that SCFAs produced by the gut microbial community participate in preventing the development of T2D in obesity in Mongolians.

Gut microbial features and dietary fiber intake predict gut microbiota response to resistant starch supplementation

ABSTRACT Resistant starch (RS) consumption can have beneficial effects on metabolic health, but the response, in terms of effects on the gut microbiota and host physiology, varies between individuals. Factors predicting the response to RS are not yet established and would be useful for developing precision nutrition approaches that maximize the benefits of dietary fiber intake. We sought to identify predictors of gut microbiota response to RS supplementation. We enrolled 76 healthy adults into a 7-week crossover study with 59 individuals completing the study. Participants consumed RS type 2 (RS2), RS type 4 (RS4), and digestible starch, for 10 d each with 5-d washout periods in between. We collected fecal and saliva samples and food records during each treatment period. We performed 16S rRNA gene sequencing and measured fecal short-chain fatty acids (SCFAs), salivary amylase (AMY1) gene copy number, and salivary amylase activity (SAA). Dietary fiber intake was predictive of the relative abundance of several amplicon sequence variants (ASVs) at the end of both RS treatments. AMY1-related metrics were not predictive of response to RS. SAA was only predictive of the relative abundance of one ASV after digestible starch supplementation. Interestingly, SCFA concentrations increased the most during digestible starch supplementation. Treatment order (the order of consumption of RS2 and RS4), alpha diversity, and a subset of ASVs were predictive of SCFA changes after RS supplementation. Based on our findings, dietary fiber intake and gut microbiome composition would be informative if assessed prior to recommending RS supplementation because these data can be used to predict changes in specific ASVs and fecal SCFA concentrations. These findings lay a foundation to support the premise that using a precision nutrition approach to optimize the benefits of dietary fibers such as RS could be an effective strategy to compensate for the low consumption of dietary fiber nationwide.

Improvement of insulin sensitivity by dietary fiber consumption during late pregnant sows is associated with gut microbiota regulation of tryptophan metabolism

BackgroundDietary fiber (DF) consumption was reported to improve insulin sensitivity, change the tryptophan metabolism, and alter the gut microbiota. Herein, this study aimed to investigate the effects of DF consumption on insulin sensitivity, tryptophan metabolism, and gut microbiota composition in sows during late pregnancy, and explore the relationship between tryptophan metabolites and insulin sensitivity regulated by DF supplementation.ResultsTwelve sows were randomly assigned to two dietary treatment groups (six/group): the low-fiber (LF) group, which was fed a basal diet, and the high-fiber (HF) group, which was fed the basal diet supplemented with 22.60 g/kg inulin and 181.60 g/kg cellulose. During late pregnancy, meal test, glucose tolerance test, and insulin challenge test were used to investigate the insulin sensitivity of sows, using the percutaneous brachiocephalic vein catheterization technique. High DF consumption resulted in improved insulin sensitivity, especially during the second and third trimesters, and promoted serotonin production from tryptophan. Additionally, plasma serotonin concentration was positively correlated with the insulin sensitivity index during late pregnancy. Moreover, DF consumption elevated fecal short-chain fatty acid (SCFA) concentrations, altered fecal microbial diversity, and increased the abundances of Rikenellaceae_RC9_gut_group, Alloprevotella, Parabacteroides, Roseburia, and Sphaerochaeta, which were positively correlated to plasma serotonin concentration.ConclusionsDF consumption improved insulin sensitivity during late pregnancy in sows, which improved microbial diversity in fecal samples and increased fecal SCFA concentrations, resulting in a positive correlation with plasma serotonin level.

Effects of dietary fiber and biotic supplementation on apparent total tract macronutrient digestibility and the fecal characteristics, metabolites, and microbiota of healthy adult dogs.

Dietary fibers and biotics have been shown to support gastrointestinal health in dogs, but are usually tested individually. There is value in testing fiber-biotic combinations that are commonly used commercially. Therefore, this study was conducted to determine the apparent total tract macronutrient digestibility (ATTD) of diets supplemented with fibers or biotics and to evaluate their effects on the fecal characteristics, metabolites, microbiota, and immunoglobulin A (IgA) concentrations of dogs. Twelve healthy adult female beagle dogs (age= 6.2 ± 1.6 yr; body weight = 9.5 ± 1.1kg) were used in a replicated 3 x 3 Latin square design to test three treatments: 1) control diet based on rice, chicken meal, tapioca starch, and cellulose + a placebo treat (CT); 2) diet based on rice, chicken meal, garbanzo beans, and cellulose + a placebo treat (GB); 3) diet based on rice, chicken meal, garbanzo beans, and a functional fiber/prebiotic blend + a probiotic-containing treat (GBPP). In each 28-day period, a 22-day diet adaptation was followed by a 5-day fecal collection phase. Fasted blood samples were collected on day 28. Data were analyzed using the Mixed Models procedure of SAS 9.4, with P<0.05 being significant and P<0.10 being trends. ATTD of dry matter, organic matter, and energy were lower (P<0.001) and DM fecal output was higher (P<0.01) in dogs fed GBPP than CT or GB, whereas ATTD of crude protein was higher (P<0.001) in dogs fed CT and GBPP than GB. ATTD of fat was higher (P<0.001) and wet fecal output was lower (P<0.01) in dogs fed CT than GB or GBPP. Fecal DM% was higher (P<0.001) in dogs fed CT than GBPP or GB, and higher in dogs fed GBPP than GB. Fecal short-chain fatty acid concentrations were higher (P<0.001) in dogs fed GB than CT or GBPP, and higher in dogs fed GB than GBPP. Fecal IgA concentrations were higher (P<0.01) in dogs fed GB than CT. Fecal microbiota populations were affected by diet, with alpha diversity being higher (P<0.01) in dogs fed GB than CT, and beta diversity shifting following dietary fiber and biotic supplementation. The relative abundance of 24 bacterial genera were altered in dogs fed GB or GBPP than CT. Serum triglyceride concentrations were lower in dogs fed GB than GBPP or CT. Our results demonstrate that legume-based dietary fibers, with or without prebiotics and probiotics, reduce ATTD, increase stool output, beneficially shift fecal metabolites and microbiota, and reduce blood lipids of adult dogs.

#2070 Associations of fecal and plasma levels of SCFAs with gut microbiota and clinical characteristics in non-dialysis renal anemia patients

Abstract Background and Aims Renal anemia is one of the most common complications of Chronic Kidney Disease (CKD). The gut-kidney axis hypothesis has led to numerous studies showing that patients with CKD have a distinct gut microbiota structure compared with controls and that changes in gut microbiota correlate with disease severity and progression. The short-chain fatty acids (SCFAs) are speculated to be pivotal in the gut-kidney crosstalk. However, the role of SCFAs in renal anemia has not been elucidated. This study aimed to explore and compare the fecal and plasma levels of SCFAs in non-dialysis renal anemia patients and healthy controls to reveal the potential interactions among SCFAs, gut microbiota, and clinical features of renal anemia, which may provide new light on further studies. Method A cohort of 30 non-dialysis renal anemia patients and 20 healthy controls were recruited from the First Affiliated Hospital of Zhengzhou University. Gut microbiota was analyzed using 16S rRNA gene amplification sequencing. Fecal and plasma concentrations of SCFAs were measured using GC-MS/MS platform. The clinical characteristics of patients with renal anemia and controls were evaluated. Results Renal anemia patients displayed altered microbiota composition compared to healthy subjects. The relative abundance of Enterobacterales, Enterobacteriaceae, Escherichia-Shigella, and Escherichia-coli were higher in patients with renal anemia, and the Lachnospiraceae family decreased in renal anemia patients. In contrast, the relative abundance of Lachnospirales, Lachnospiraceae, and Bacteroides vulgatus was higher in the control group. Patients with renal anemia had higher fecal and plasma concentrations of SCFAs compared to controls. The fecal and plasma concentrations of SCFAs were significantly different not only between the patients with renal anemia and controls but also in the different severity of renal anemia. Moreover, different types of SCFAs are intimately associated with clinical characteristics. The applications of medications may exert effects on the fecal and plasma SCFAs. A positive correlation was obtained between Lachnospirales and the plasma SCFAs. The levels of acetic acid and caproic acid in fecal and the levels of acetic acid, propionic acid, and butyric acid in plasma were all positively correlated with the abundance of Cyanobacteria. Conclusion The gut metabolites SCFAs are tightly linked to the alterations of gut microbiota and clinical characteristics of renal anemia. Further studies are warranted to elucidate the relationships more in-depth.

Meta-analysis of shotgun sequencing of gut microbiota in Parkinson’s disease

We aimed to identify gut microbial features in Parkinson’s disease (PD) across countries by meta-analyzing our fecal shotgun sequencing dataset of 94 PD patients and 73 controls in Japan with five previously reported datasets from USA, Germany, China1, China2, and Taiwan. GC-MS and LC-MS/MS assays were established to quantify fecal short-chain fatty acids (SCFAs) and fecal polyamines, respectively. α-Diversity was increased in PD across six datasets. Taxonomic analysis showed that species Akkermansia muciniphila was increased in PD, while species Roseburia intestinalis and Faecalibacterium prausnitzii were decreased in PD. Pathway analysis showed that genes in the biosyntheses of riboflavin and biotin were markedly decreased in PD after adjusting for confounding factors. Five out of six categories in carbohydrate-active enzymes (CAZymes) were decreased in PD. Metabolomic analysis of our fecal samples revealed that fecal SCFAs and polyamines were significantly decreased in PD. Genes in the riboflavin and biotin biosyntheses were positively correlated with the fecal concentrations of SCFAs and polyamines. Bacteria that accounted for the decreased riboflavin biosynthesis in Japan, the USA, and Germany were different from those in China1, China2, and Taiwan. Similarly, different bacteria accounted for decreased biotin biosynthesis in the two country groups. We postulate that decreased SCFAs and polyamines reduce the intestinal mucus layer, which subsequently facilitates the formation of abnormal α-synuclein fibrils in the intestinal neural plexus in PD, and also cause neuroinflammation in PD.

Quantifying fecal and plasma short-chain fatty acids in healthy Thai individuals

Short-chain fatty acids (SCFAs) are involved in important physiological processes such as gut health and immune response, and changes in SCFA levels can be indicative of disease. Despite the importance of SCFAs in human health and disease, reference values for fecal and plasma SCFA concentrations in healthy individuals are scarce. To address this gap in current knowledge, we developed a simple and reliable derivatization-free GC-TOFMS method for quantifying fecal and plasma SCFAs in healthy individuals. We targeted six linear- and seven branched-SCFAs, obtaining method recoveries of 73–88% and 83–134% in fecal and plasma matrices, respectively. The developed methods are simpler, faster, and more sensitive than previously published methods and are well suited for large-scale studies. Analysis of samples from 157 medically confirmed healthy individuals showed that the total SCFAs in the feces and plasma were 34.1 ± 15.3 µmol/g and 60.0 ± 45.9 µM, respectively. In fecal samples, acetic acid (Ace), propionic acid (Pro), and butanoic acid (But) were all significant, collectively accounting for 89% of the total SCFAs, whereas the only major SCFA in plasma samples was Ace, constituting of 93% of the total plasma SCFAs. There were no statistically significant differences in the total fecal and plasma SCFA concentrations between sexes or among age groups. The data revealed, however, a positive correlation for several nutrients, such as carbohydrate, fat, iron from vegetables, and water, to most of the targeted SCFAs. This is the first large-scale study to report SCFA reference intervals in the plasma and feces of healthy individuals, and thereby delivers valuable data for microbiome, metabolomics, and biomarker research.

Green banana biomass anti-obesogenic, anti-hyperlipidemic, antidiabetic, and intestinal function potential effects: a systematic review.

Apparently, the consumption of resistant-starch food sources, such as green banana biomass, stimulates the proliferation of short-chain fatty acid intestinal bacteria producers, which can contribute to intestinal health and reduce the risk of chronic diseases. However, the available scientific evidence is scarce and no study has systematically evaluated such evidence. The aim of this study was to analyze the potential effects of green banana biomass on anthropometry, body composition, and biochemical and intestinal variables in humans and animals. The Cochrane Library, Embase, Medline/PubMed, Scopus, and Web of Science electronic databases were searched in January 2024 for eligible articles. Studies that tested the effects of cooked peeled or unpeeled green banana on anthropometric, biochemical, and/or intestinal variables were included. This systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The classification and assessment of the quality of studies were based on the relevant criteria related to the design of these studies and the quality criteria checklist of the Academy of Nutrition and Dietetics manual. Twelve studies published between 2001 and 2021 were included in the review. The results of human studies indicate that the ingestion of green banana biomass controlled intestinal dysfunction (50-300 g/day for 5-14 days or 30 g/day for 8 wk) in children, and showed potential anti-obesogenic, anti-hyperlipidemic, and antidiabetic (40 g/day for 24 wk) effects in adults. In rats, biomass consumption led to potential anti-obesogenic (25 g/day for 8 wk), anti-hyperlipidemic, and antidiabetic (∼8-30 g/day for 12 wk) effects. Consumption of green banana biomass seems to exert beneficial effects on intestinal function and potential effects on obesity, dyslipidemia, and diabetes. These effects may be related to increased fecal short-chain fatty acid concentrations as a result of type 3 resistant starch present in biomass. Open Science Framework (OSF) (https://doi.org/10.17605/OSF.IO/TKCWV).

Fibras solúvel e insolúvel em dietas de leitões na creche

This study evaluated the effect of diets containing low levels of soluble and insoluble fiber sources on performance, diarrhea score, chemical and physical characteristics of feces, and behavior in weaning piglets. Thirty-six weaned piglets of 30 days of age with an initial body weight of 8.8 kg were distributed in 36 pens using a completely randomized design in an experimental period of 21 days. The experimental treatments were the Control diet (CONT), the Control diet + 1% beet pulp inclusion (SBP), and the Control diet + 1% lignocellulose inclusion (LCE, Arbocel®). Feed and water were available ad libitum. Body weight and feed intake were measured weekly to calculate the average daily intake, weight gain, and feed conversion ratio. The fecal consistency was determined visually twice daily, classifying feces according to three scores. To determine fecal pH and concentration of fecal short-chain fatty acids (SCFA), samples of fresh feces were collected two weeks after weaning and measured by a digital pH meter and gas chromatography, respectively. The behavior of piglets was observed once a week, using four animals per treatment, from 14:00 to 16:00, every 12 min. Fibre sources had no effect (P&gt;0.05) on performance, except in the period 15 to 21 days after weaning, which was a tendency (P=0.061) of feed intake decrease in SBP and LCE diets. Fiber sources did not affect the fecal consistency score (P&gt;0.05). However, piglets fed SBP and LCE showed a tendency (P&lt;0.10) to have less diarrhea incidence 15 to 21 days post-weaning and in the entire experimental period. Fecal pH and SCFA concentration were not influenced by fiber source (P&gt;0.05), with acetic, propionic, and butyric acids representing around 71%, 19%, and 10% of the total, respectively. Fiber sources did not influence the social and feeding behavior of weaning piglets (P&gt;0.05). Diets containing 1% fiber sources did not alter performance, diarrhea score, fecal pH, fecal SCFA concentration, or feeding and social behavior of weaned piglets.

Protective effect of chicken yolk antibody Y against Campylobacter jejuni induced diarrhea in cats.

Campylobacter jejuni (C. jejuni) is a common pathogen that often causes diarrhea, loss of appetite, and even enteritis in domestic cats, affecting their growth and development, especially in kittens under 6 months of age. Oral passive immunization with chicken yolk antibody Y has been proved effective for the treatment of gastrointestinal pathogen infections due to its high specificity. In this study, C. jejuni was isolated from diarrheal cat feces, and the specific egg yolk antibody Y against C. jejuni was demonstrated to effectively inhibit its proliferation in vitro experiments. To evaluate the effect of anti-C. jejuni IgY, the mouse C. jejuni infection model was established and it was found that IgY could alleviate C. jejuni-induced clinical symptoms. Consistent with these results, the reduction of pro-inflammatory factors and intestinal colonization by C. jejuni in the IgY-treated groups, especially in the high dose group. We then evaluated the protective effect of IgY on young Ragdoll cats infected with C. jejuni. This specific antibody reduced the rate of feline diarrhea, protected the growth of young cats, inhibited systemic inflammatory hyperactivation, and increased fecal short-chain fatty acid concentrations. Notably, IgY may have a protective role by changing intestinal amino acid metabolism and affecting C. jejuni chemotaxis. Collectively, specific IgY is a promising therapeutic strategy for C. jejuni-induced cat diarrhea.

XX sex chromosome complement modulates immune responses to heat-killed Streptococcus pneumoniae immunization in a microbiome-dependent manner.

Differences in male vs. female immune responses are well-documented and have significant clinical implications. While the immunomodulatory effects of sex hormones are well established, the contributions of sex chromosome complement (XX vs. XY) and gut microbiome diversity on immune sexual dimorphisms have only recently become appreciated. Here we investigate the individual and collaborative influences of sex chromosome complements and gut microbiota on humoral immune activation. Male and female Four Core Genotype (FCG) mice were immunized with heat-killed Streptococcus pneumoniae (HKSP). Humoral immune responses were assessed, and X-linked immune-related gene expression was evaluated to explain the identified XX-dependent phenotype. The functional role of Kdm6a, an X-linked epigenetic regulatory gene of interest, was evaluated ex vivo using mitogen stimulation of B cells. Additional influences of the gut microbiome on sex chromosome-dependent B cell activation was also evaluated by antibiotically depleting gut microbiota prior to HKSP immunization. Reconstitution of the depleted microbiome with short-chain fatty acid (SCFA)-producing bacteria tested the impact of SCFAs on XX-dependent immune activation. XX mice exhibited higher HKSP-specific IgM-secreting B cells and plasma cell frequencies than XY mice, regardless of gonadal sex. Although Kdm6a was identified as an X-linked gene overexpressed in XX B cells, inhibition of its enzymatic activity did not affect mitogen-induced plasma cell differentiation or antibody production in a sex chromosome-dependent manner ex vivo. Enhanced humoral responses in XX vs. XY immunized FCG mice were eliminated after microbiome depletion, indicating that the microbiome contributes to the identified XX-dependent immune enhancement. Reconstituting microbiota-depleted mice with select SCFA-producing bacteria enhanced fecal SCFA concentrations and increased humoral responses in XX, but not XY, FCG mice. However, exposure to the SCFA propionate alone did not enhance mitogenic B cell stimulation in ex vivo studies. FCG mice have been used to assess sex hormone and sex chromosome complement influences on various sexually dimorphic traits. The current study indicates that the gut microbiome impacts humoral responses in an XX-dependent manner, suggesting that the collaborative influence of gut bacteria and other sex-specific factors should be considered when interpreting data aimed at delineating the mechanisms that promote sexual dimorphism.

Association of short-chain fatty acids and the gut microbiome with type 2 diabetes: Evidence from the Henan Rural Cohort

Background and aimsHuman studies about short-chain fatty acids (SCFAs), the gut microbiome, and Type 2 diabetes (T2DM) are limited. Here we explored the association between SCFAs and T2DM and the effects of gut microbial diversity on glucose status in rural populations. Methods and resultsWe performed a cross-sectional study from the Henan Rural Cohort and collected stool samples. Gut microbiota composition and faecal SCFA concentrations were measured by 16S rRNA and GC-MS. The population was divided based on the tertiles of SCFAs, and logistic regression models assessed the relationship between SCFAs and T2DM. Generalized linear models tested the interactions between SCFAs and gut microbial diversity on glucose indicators (glucose, HbAlc and insulin). Compared to the lowest tertile of total SCFA, acetate and butyrate, the highest tertile exhibited lower T2DM prevalence, with ORs and 95% CIs of 0.291 (0.085–0.991), 0.160 (0.044–0.574) and 0.171 (0.047–0.620), respectively. Restricted cubic spline demonstrated an approximately inverse S-shaped association. We also noted interactions of the ACE index with the highest tertile of valerate on glucose levels (P-interaction = 0.022) and the Shannon index with the middle tertile of butyrate on insulin levels (P-interaction = 0.034). Genus Prevotella_9 and Odoribacter were inversely correlated with T2DM, and the genus Blautia was positively associated with T2DM. These bacteria are common SCFA-producing members. ConclusionsInverse S-shaped associations between SCFAs (total SCFA, acetate, and butyrate) and T2DM were observed. Valerate and butyrate modify glucose status with increasing gut microbial diversity.

Вікові особливості перебігу ротавірусної інфекції в дітей та внесок осмотичного компонента в патогенез діарейного синдрому залежно від віку

Purpose - to identify the age-specific features of the course of rotavirus infection (RVI) in children and to clarify the role of the osmolar component in the pathogenesis of diarrheal syndrome in young children. Materials and methods. 100 young children with RVI were examined. Children were divided into 3 age subgroups: 1-6 months, 6-12 months and 13-24 months. A comparative analysis of the manifestation and features of the clinical course of the disease was carried out in the subgroups. A comparative assessment of the level of undigested sugars in feces and concentrations of short-chain fatty acids (SCFA) in the dynamics of the disease were carried out. The total level of carbohydrates in feces was determined on the 2nd, 5th, 7th and 10th day of RVI using the Benedict test. Concentrations of SCFA (acetate, propionate, butyrate) were determined on 2nd, 5th and 10th days by liquid chromatography. As physiological indicators of the total amount of carbohydrates in the feces and fecal concentrations of SCFA, the indicators of 30 relatively healthy children were taken. The "STATISTICA for Windows 13" program was used for statistical processing of the obtained data. Since the quantitative values that were analyzed had a distribution that differed from normal, non-parametric statistical methods were applied. Results. Children 1-6 months of age with RVI less often had fever and vomiting (p˂0.05), had longer diarrhea (p˂0.05), which was more often accompanied by flatulence, intestinal colic (p˂0.05), than children 13-24 months of age. Children of this subgroup had the highest levels of carbohydrates in feces in the acute period of RVI (р˂0.05 on the 2nd and 5th day relative to children 6-12 months and 13-24 months of age) and in the period of convalescence (р˂0.05 on 10th day for children 13-24 months of age). In all subgroups of children, reduced concentrations of SCFA were noted in the acute period of RVI (p&gt;0.05 relative to the reference values from the 3rd to the 5th day). The most pronounced decrease in the total concentrations of SCFA (p&lt;0.01 relative to the reference values) during the entire period of RVI were observed in children 1-6 months of aged. Conclusions. RVI is characterized by longer diarrhea which is more often accompanied by flatulence and intestinal colic in children 1-6 months of age, while children 13-24 months of age more often have fever and vomiting. The most pronounced disturbances of carbohydrate metabolism in the intestines and changes in the functional activity of the intestinal microflora during RVI occur in children 1-6 months of age. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Alteration of gut microbiota in post-stroke depression patients with Helicobacter pylori infection

Background: Several studies have identified an association between the gut microbiome and post-stroke depression(PSD), and Helicobacter pylori(H. pylori) infection cause significant alterations in the composition of the gastrointestinal microbiome. However, evidence regarding the role of the H. pylori infection in promoting PSD is still lacking. Here, we conducted a retrospective study to explore risk factors associated with PSD.Methods: Patients with cerebral infarction were consecutively enrolled from December 2021 to October 2022. The diagnosis of PSD is based on the DSM-V criteria, and the Hamilton Depression Rating Scale(HAMD) was used to identify patients with PSD. White matter lesions were evaluated using magnetic resonance imaging(MRI) and H. pylori infection was detected by 13C-urea breath test. Further, 16S rRNA gene sequencing was used to evaluate the changes in gut microbiota composition of fecal samples from PSD patients. The concentration of short-chain fatty acids(SCFAs) was determined by gas chromatography–mass spectrometry(GC–MS).Results: Multivariate regression analysis showed that deep white matter lesions(DWMLs) [odds ratio(OR) 3.382, 95% confidence interval(CI) 1.756–6.512; P = 0.001] and H. pylori infection(OR 2.186, 95% CI 1.149–4.159; P = 0.017) were the independent risk factors for PSD. Patients with H. pylori infection had more severe depressive symptoms than patients without infection. Intestinal microbiota was significantly different between H. pylori-positive PSD[H. pylori(+)] patients and H. pylori-negative PSD[H. pylori (−)] patients. Fecal SCFAs concentrations were significantly reduced in the H. pylori(+) group compared to the negative ones.Conclusion: DWMLs and H. pylori infection may play important roles in the development of PSD. H. pylori infection is likely to be involved in the pathogenesis of PSD by altering the intestinal flora.

Comparison of a Daily Steviol Glycoside Beverage compared with a Sucrose Beverage for Four Weeks on Gut Microbiome in Healthy Adults

BackgroundRecent studies suggest that some nonnutritive sweeteners (NNS) have deleterious effects on the human gut microbiome (HGM). The effect of steviol glycosides on the HGM has not been well studied. ObjectiveWe aimed to evaluate the effects of stevia- compared with sucrose-sweetened beverages on the HGM and fecal short-chain fatty acid (SCFA) profiles. MethodsUsing a randomized, double-blinded, parallel-design study, n = 59 healthy adults [female/male, n = 36/23, aged 31±9 y, body mass index (BMI): 22.6±1.7 kg/m2] consumed 16 oz of a beverage containing either 25% of the acceptable daily intake (ADI) of stevia or 30 g of sucrose daily for 4 weeks followed by a 4-week washout. At weeks 0 (baseline), 4, and 8, the HGM was characterized via shotgun sequencing, fecal SCFA concentrations were measured using ultra-high performance liquid chromatography-tandem mass spectrometry and anthropometric measurements, fasting serum glucose, insulin and lipids, blood pressure, pulse, and 3-d diet records were obtained. ResultsThere were no significant differences in the HGM or fecal SCFA between the stevia and sucrose groups at baseline (P > 0.05). At week 4 (after intervention), there were no significant differences in the HGM at the phylum, family, genus, or species level between the stevia and sucrose groups and no significant differences in fecal SCFA. At week 4, BMI had increased by 0.3 kg/m2 (P = 0.013) in sucrose compared with stevia, but all other anthropometric and cardiometabolic measures and food intake did not differ significantly (P > 0.05). At week 8 (after washout), there were no significant differences in the HGM, fecal SFCA, or any anthropometric or cardiometabolic measure between the stevia and sucrose groups (P > 0.05). ConclusionsDaily consumption of a beverage sweetened with 25% of the ADI of stevia for 4 weeks had no significant effects on the HGM, fecal SCFA, or fasting cardiometabolic measures, compared with daily consumption of a beverage sweetened with 30 g of sucrose. Trial registrationclinicaltrials.gov as NCT05264636