Fecal Short-chain Fatty Acid Concentrations Research Articles

Changes in intestinal parameters and their association with dietary patterns in rotational shift workers

ABSTRACT Circadian rhythm disturbances induced by rotating shift work contribute to development of metabolic disorders. However, their effects on intestinal parameters such as epithelial permeability and fecal short chain fatty acid (SCFA) levels have not been established yet. This study was planned to investigate the changes in intestinal integrity, fecal SCFA levels, gut microbiota and nutritional intake of rotational shift workers. The study was conducted on ten male rotational shift workers, 25–40 years old. Circadian rhythm disruption was assumed to have occurred after 14 days in the night shift. Dietary data which was obtained by using 24 h record for 7 days, physical activity data, anthropometric measurements, fecal and blood samples were collected during day and night shift. Changes in dietary consumption, anthropometric measurements, blood chemistry and intestinal epithelial permeability indicator according to day and night shifts were not significant (p > .05). Additionally, acetic, propionic and total SCFA were associated with the intestinal permeability biomarker in night shift, but not in day shift (p < .05). Consumption of dark green vegetables and beans and peas was positively associated with fecal isobutyric acid and fecal total SCFA concentration (r = 0.685, p = .029; r = 0.695, p = .026, respectively). The proportions of the genus including Blautia, Bifidobacterium, Dialister, and Ruminococcus gnavus group increased when individuals shifted to the night shift. Gut microbiota changes responding to circadian rhythm disruption became more prominent when consumed high sugar diet. So, changes have been observed in the gut microbiota of rotational shift workers, especially in individuals with certain dietary pattern. Moreover, in individuals with the circadian rhythm disruption SCFAs levels have been demonstrated to be associated with intestinal barrier integrity. A better understanding of the relation among fecal SCFAs, gut microbiota, intestinal epithelial permeability and circadian rhythm disruption is necessary for the development of new dietary strategies for gut health.

Camelina sativa Oil Treatment Alleviates Castor Oil-Induced Diarrhea in ICR Mice by Regulating Intestinal Flora Composition.

Diarrhea, occurring due to intestinal flora disturbance, is potentially lethal, and its current treatments have adverse effects such as constipation and vomiting. Camelina sativa oil (CSO) is a cooking ingredient and natural remedy used in several countries; however, its pharmacological effects on intestinal health remain unknown. Here, we explored the CSO treatment effects on intestinal flora in male ICR mice with castor oil-induced diarrhea. The rate and degree of loose stools, the diarrhea index, serum inflammatory indices, fecal short-chain fatty acids (SCFAs), and the diversity and abundance of intestinal flora were measured. Castor oil-administered mice experienced diarrhea, reduced intestinal flora diversity and fecal SCFAs concentrations, altered intestinal flora composition, and increased serum proinflammatory indices. In contrast, CSO treatment relieved diarrhea, improved intestinal flora composition, and increased the relative abundance of Lactobacillus and Lachnospiraceae. Additionally, CSO significantly increased the concentrations of fecal propionic acid, valeric acid, isovaleric acid, and serum sIgA, while it reduced those of serum interleukin-17. These findings suggest that CSO could be a promising preventive agent against diarrhea.

Additional Resistant Starch from One Potato Side Dish per Day Alters the Gut Microbiota but Not Fecal Short-Chain Fatty Acid Concentrations.

The composition of the gut microbiota and their metabolites are associated with cardiometabolic health and disease risk. Intake of dietary fibers, including resistant starch (RS), has been shown to favorably affect the health of the gut microbiome. The aim of this research was to measure changes in the gut microbiota and fecal short-chain fatty acids as part of a randomized, crossover supplemental feeding study. Fifty participants (68% female, aged 40 ± 13 years, BMI 24.5 ± 3.6 kg/m2) completed this study. Potato dishes (POT) contained more RS than refined grain dishes (REF) (POT: 1.31% wet basis (95% CI: 0.94, 1.71); REF: 0.73% wet basis (95% CI: 0.34, 1.14); p = 0.03). Overall, potato dish consumption decreased alpha diversity, but beta diversity was not impacted. Potato dish consumption was found to increase the abundance of Hungatella xylanolytica, as well as that of the butyrate producing Roseburia faecis, though fecal butyrate levels were unchanged. Intake of one potato-based side dish per day resulted in modest changes in gut microbiota composition and diversity, compared to isocaloric intake of refined grains in healthy adults. Studies examining foods naturally higher in RS are needed to understand microbiota changes in response to dietary intake of RS and associated health effects.

Gut microbiota and short chain fatty acids partially mediate the beneficial effects of inulin on metabolic disorders in obese ob/ob mice.

Mounting evidence has linked both obesity and metabolic disorders with dysbiosis of the gut microbiota. Dietary inulin is conducive to modulating this dysbiosis, and represents a potential means to improve disorders of glucose and lipid metabolism. However, the mechanisms underlying these improvements are largely unclear. Obese ob/ob mice were fed a standard chow, a low fiber diet (LFD) or a high fiber diet (HFD) for 4weeks, and the body weight, fecal short chain fatty acids (SCFAs) level, and plasma and liver lipid profiles were analyzed. Oral glucose tolerance testing, and gut microbiota sequencing were also conducted. Dietary inulin improved the dysbiosis of the gut microbiota, attenuated the decrease in phylum Bacteroidetes, repressed the increase of phylum Firmicutes, and led to an increase in the ratio of Firmicutes/Bacteroidetes. At the family level, inulin promoted the expansion of SCFAs-producing Ruminococcaceae and Lachnospiraceae bacteria, which increased the fecal SCFAs concentrations. At the genus level, inulin increased the levels of Bacteroides and Bifidobacteria. Furthermore, our results revealed that there was enhanced expression of angiopoietin-like protein 4 (ANGPTL4), which might be induced by the higher production of SCFAs, and this may underlie the improvements in the disorders of glucose and lipid metabolism seen in mice with added dietary inulin. In conclusion, inulin may ameliorate metabolic disorders by remodeling the gut microbiota and increasing the production of SCFAs, which might be mediated by the ANGPTL4-related signaling pathway. Interventions targeting the gut microbiota warrant further investigation as a novel therapy for metabolic diseases. PRACTICAL APPLICATIONS: Mounting evidence has linked both obesity and metabolic disorders with dysbiosis of the gut microbiota. Dietary inulin is conducive to modulating this dysbiosis, and represents a potential means to improve disorders of glucose and lipid metabolism. However, the mechanisms underlying these improvements are largely unclear. In the present study, we investigated the effects of dietary fiber (inulin) on metabolic homeostasis using ob/ob mice. The results of our study demonstrate that inulin-induced remodeling of the gut microbiota resulted in increased production of short chain fatty acids (SCFAs), leading to the enhanced expression of angiopoietin-like protein 4 (ANGPTL4), which improved the glucose and lipid metabolism. Our results suggest that the gut microbiota, SCFAs and ANGPTL4 pathway at least partially mediate the beneficial effects of inulin on metabolic disorders in ob/ob mice.

A low glycemic index, energy-restricted diet but not Lactobacillus rhamnosus supplementation changes fecal short-chain fatty acid and serum lipid concentrations in women with overweight or obesity and polycystic ovary syndrome.

To evaluate if changes in fecal short-chain fatty acids (SCFA) content with an energy-restricted diet and with/without 12 × 109 CFU/day of Lactobacillus rhamnosus supplementation affect the abundance of selected gut bacteria and lipid profile in overweight and obese women with PCOS. This randomized controlled trial involved 40 overweight and obese women with a mean age of 28.8 ± 4.8 years diagnosed with PCOS. The subjects were randomly assigned to an energy-restricted diet group (D group; n = 21) or energy-restricted diet + Lactobacillus rhamnosus supplementation group (DP group; n=19). SCFA, selected gut bacteria (Akkermansia muciniphila, Bifidobacterium longum, and Faecalibacterium prausnitzii) abundance, lipid profile and anthropometric parameters were evaluated at baseline and after twenty weeks of intervention. The energy-restricted diet significantly reduced body weight, BMI, fat mass, acetic and butyric acids, and improved the lipid profile (total cholesterol, low-density lipoprotein cholesterol, and triglycerides) of both groups. Changes in the molar ratio of SCFA towards the correct ratio were also observed. All the results were independent of Lactobacillus rhamnosus supplementation, with no significant differences between the two groups. Twenty weeks of probiotic supplementation has no additional beneficial effects on selected gut bacteria abundance, SCFA levels, or lipid profile beyond the effect of an energy-restricted diet in overweight and obese women with PCOS.

The Association Between Fecal Short-Chain Fatty Acids, Gut Microbiota, and Visceral Fat in Monozygotic Twin Pairs.

PurposeTo examine the association of short-chain fatty acids (SCFAs), gut microbiota and obesity in individual twins and to control for genetic and shared environmental effects by studying monozygotic intrapair differences.Patients and MethodsThe study recruited 20 pairs of monozygotic twins. Body composition measurements were performed by using the multi-frequency bioelectrical impedance technique. SCFAs were extracted from feces and quantified by gas chromatography-mass spectrometer. Gut microbiota was evaluated by 16S rRNA gene sequencing.ResultsFecal SCFAs were negatively correlated with adiposity parameters including body mass index, visceral adipose tissue and waist circumference (all P < 0.05). Metastat analysis showed that the top 5 relatively abundant bacterial taxa of viscerally obese and non-obese groups were Bacteroides, Collinsella, Eubacterium rectale group, Lachnoclostridium, and Tyzzerella. Participants with visceral obesity had lower abundance of Bacteroides and Collinsella compared to non-obese patients (P < 0.05). Among them, the abundance of Collinsella was positively correlated with acetic acid concentrations (r = 0.63, P = 0.011). There were no significant intrapair differences in each SCFA concentrations between the twins in our study (P > 0.05).ConclusionLow fecal concentrations of SCFAs were associated with visceral obesity, and the gut microbiota might be involved in the underlying mechanism.

Suppression of high-fat-diet-induced obesity in mice by dietary folic acid supplementation is linked to changes in gut microbiota.

To investigate whether the effects of dietary folic acid supplementation on body weight gain are mediated by gut microbiota in obesity. Male C57 BL/6J conventional (CV) and germ-free (GF) mice both aged three to four weeks were fed a high-fat diet (HD), folic acid-deficient HD (FD-HD), folic acid-supplement HD (FS-HD) and a normal-fat diet (ND) for 25weeks. Faecal microbiota were analyzed by 16S rRNA high-throughput sequencing, and the mRNA expression of genes was determined by the real-time RT-PCR. Short-chain fatty acids (SCFAs) in faeces and plasma were measured using gas chromatography-mass spectrometry. In CV mice, HD-induced body weight gain was inhibited by FS-HD, accompanied by declined energy intake, smaller white adipocyte size, and less whitening of brown adipose tissue. Meanwhile, the HD-induced disturbance in the expression of fat and energy metabolism-associated genes (Fas, Atgl, Hsl, Ppar-α, adiponectin, resistin, Ucp2, etc.) in epididymal fat was diminished, and the dysbiosis in faecal microbiota was lessened, by FS-HD. However, in GF mice with HD feeding, dietary folic acid supplementation had almost no effect on body weight gain and the expression of fat- and energy-associated genes. Faecal or plasma SCFA concentrations in CV and GF mice were not altered by either FD-HD or FS-HD feeding. Dietary folic acid supplementation differently affected body weight gain and associated genes' expression under HD feeding between CV and GF mice, suggesting that gut bacteria might partially share the responsibility for beneficial effects of dietary folate on obesity.

Higher total faecal short-chain fatty acid concentrations correlate with increasing proportions of butyrate and decreasing proportions of branched-chain fatty acids across multiple human studies.

Metabolites produced by microbial fermentation in the human intestine, especially short-chain fatty acids (SCFAs), are known to play important roles in colonic and systemic health. Our aim here was to advance our understanding of how and why their concentrations and proportions vary between individuals. We have analysed faecal concentrations of microbial fermentation acids from 10 human volunteer studies, involving 163 subjects, conducted at the Rowett Institute, Aberdeen, UK over a 7-year period. In baseline samples, the % butyrate was significantly higher, whilst % iso-butyrate and % iso-valerate were significantly lower, with increasing total SCFA concentration. The decreasing proportions of iso-butyrate and iso-valerate, derived from amino acid fermentation, suggest that fibre intake was mainly responsible for increased SCFA concentrations. We propose that the increase in % butyrate among faecal SCFA is largely driven by a decrease in colonic pH resulting from higher SCFA concentrations. Consistent with this, both total SCFA and % butyrate increased significantly with decreasing pH across five studies for which faecal pH measurements were available. Colonic pH influences butyrate production through altering the stoichiometry of butyrate formation by butyrate-producing species, resulting in increased acetate uptake and butyrate formation, and facilitating increased relative abundance of butyrate-producing species (notably Roseburia and Eubacterium rectale).

Effects of Resistant Starch on Symptoms, Fecal Markers, and Gut Microbiota in Parkinson’s Disease — The RESISTA-PD Trial

The composition of the gut microbiota is linked to multiple diseases, including Parkinson’s disease (PD). Abundance of bacteria producing short-chain fatty acids (SCFAs) and fecal SCFA concentrations are reduced in PD. SCFAs exert various beneficial functions in humans. In the interventional, monocentric, open-label clinical trial “Effects of Resistant Starch on Bowel Habits, Short Chain Fatty Acids and Gut Microbiota in Parkinson’sDisease” (RESISTA-PD; ID: NCT02784145), we aimed at altering fecal SCFAs by an 8-week prebiotic intervention with resistant starch (RS). We enrolled 87 subjects in three study-arms: 32 PD patients received RS (PD + RS), 30 control subjects received RS, and 25 PD patients received solely dietary instructions. We performed paired-end 100 bp length metagenomic sequencing of fecal samples using the BGISEQ platform at an average of 9.9 GB. RS was well-tolerated. In the PD + RS group, fecal butyrate concentrations increased significantly, and fecal calprotectin concentrations dropped significantly after 8 weeks of RS intervention. Clinically, we observed a reduction in non-motor symptom load in the PD + RS group. The reference-based analysis of metagenomes highlighted stable alpha-diversity and beta-diversity across the three groups, including bacteria producing SCFAs. Reference-free analysis suggested punctual, yet pronounced differences in the metagenomic signature in the PD + RS group. RESISTA-PD highlights that a prebiotic treatment with RS is safe and well-tolerated in PD. The stable alpha-diversity and beta-diversity alongside altered fecal butyrate and calprotectin concentrations call for long-term studies, also investigating whether RS is able to modify the clinical course of PD.

Comparison of Microbial Populations in Saliva and Feces from Healthy and Celiac Adolescents with Conventional and Molecular Approaches after Cultivation on Gluten-Containing Media: An Exploratory Study.

Microbes capable of metabolizing gluten are common in various parts of the intestinal tract. In this study, saliva and fecal samples were obtained from 10 adolescents (13–18 years of age), five of which had celiac disease (CD) and five of which were healthy volunteers (HV). Culture-enriched saliva and fecal samples were compared with molecular profiling, and microorganisms displaying lysis zones on gluten-containing media (i.e., gluten-degrading microorganisms; GDMs) were isolated. In total, 45 gluten-degrading strains were isolated, belonging to 13 genera and 15 species, including Candida albicans and Veillonella. GDMs were more common in HVs compared to CD patients and more diverse in saliva compared to feces. In saliva, GDMs showed partial overlap between HVs and CD patients. Bacterial communities in fecal samples determined with amplicon sequencing significantly differed between CD patients and HVs. Overall, 7–46 of all operational taxonomic units (OTUs) per sample were below the detection limit in the fecal samples but were present in the cultivated samples, and mainly included representatives from Lactobacillus and Enterococcus. Furthermore, differences in fecal short-chain fatty-acid concentrations between CD patients and HVs, as well as their correlations with bacterial taxa, were demonstrated.

Time-Restricted Feeding in Mice Prevents the Disruption of the Peripheral Circadian Clocks and Its Metabolic Impact during Chronic Jetlag.

We used time-restricted feeding (TRF) to investigate whether microbial metabolites and the hunger hormone ghrelin can become the dominant entraining factor during chronic jetlag to prevent disruption of the master and peripheral clocks, in order to promote health. Therefore, hypothalamic clock gene and Agrp/Npy mRNA expression were measured in mice that were either chronically jetlagged and fed ad libitum, jetlagged and fed a TRF diet, or not jetlagged and fed a TRF diet. Fecal short-chain fatty acid (SCFA) concentrations, plasma ghrelin and corticosterone levels, and colonic clock gene mRNA expression were measured. Preventing the disruption of the food intake pattern during chronic jetlag using TRF restored the rhythmicity in hypothalamic clock gene mRNA expression of Reverbα but not of Arntl. TRF countered the changes in plasma ghrelin levels and in hypothalamic Npy mRNA expression induced by chronic jetlag, thereby reestablishing the food intake pattern. Increase in body mass induced by chronic jetlag was prevented. Alterations in diurnal fluctuations in fecal SCFAs during chronic jetlag were prevented thereby re-entraining the rhythmic expression of peripheral clock genes. In conclusion, TRF during chronodisruption re-entrains the rhythms in clock gene expression and signals from the gut that regulate food intake to normalize body homeostasis.

Prolonged Impairment of Short-Chain Fatty Acid and L-Isoleucine Biosynthesis in Gut Microbiome in Patients With COVID-19

Background and AimsCoronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with altered gut microbiota composition. Phylogenetic groups of gut bacteria involved in the metabolism of short chain fatty acids (SCFAs) were depleted in SARS-CoV-2–infected patients. We aimed to characterize a functional profile of the gut microbiome in patients with COVID-19 before and after disease resolution.MethodsWe performed shotgun metagenomic sequencing on fecal samples from 66 antibiotics-naïve patients with COVID-19 and 70 non–COVID-19 controls. Serial fecal samples were collected (at up to 6 times points) during hospitalization and beyond 1 month after discharge. We assessed gut microbial pathways in association with disease severity and blood inflammatory markers. We also determined changes of microbial functions in fecal samples before and after disease resolution and validated these functions using targeted analysis of fecal metabolites.ResultsCompared with non–COVID-19 controls, patients with COVID-19 with severe/critical illness showed significant alterations in gut microbiome functionality (P < .001), characterized by impaired capacity of gut microbiome for SCFA and L-isoleucine biosynthesis and enhanced capacity for urea production. Impaired SCFA and L-isoleucine biosynthesis in gut microbiome persisted beyond 30 days after recovery in patients with COVID-19. Targeted analysis of fecal metabolites showed significantly lower fecal concentrations of SCFAs and L-isoleucine in patients with COVID-19 before and after disease resolution. Lack of SCFA and L-isoleucine biosynthesis significantly correlated with disease severity and increased plasma concentrations of CXCL-10, NT- proB-type natriuretic peptide, and C-reactive protein (all P < .05).ConclusionsGut microbiome of patients with COVID-19 displayed impaired capacity for SCFA and L-isoleucine biosynthesis that persisted even after disease resolution. These 2 microbial functions correlated with host immune response underscoring the importance of gut microbial functions in SARS-CoV-2 infection pathogenesis and outcome.

112 Modulating Effects of Miscanthus Grass and Prebiotic Blends on Canine Fecal Microbiota, Metabolites, and Digestibility

Abstract Dietary fiber plays an important role in gastrointestinal health as it modulates the gut environment and promotes microbiome homeostasis. However, dietary fiber sources vary in composition, physico-chemical properties, and physiological effects. The objective of this study was to evaluate the effects of miscanthus grass fiber and prebiotic fiber blends on fecal microbiota, fecal metabolites, and apparent total tract digestibility in comparison to traditional dietary fiber sources. Animal procedures were approved by the University of Illinois Institutional Animal Care and Use Committee. Six dietary treatments were formulated to meet or exceed AAFCO nutrient profile (2018) and included either cellulose, beet pulp, miscanthus fiber, or a blend of miscanthus fiber and tomato pomace, miscanthus fiber and resistant starch, or miscanthus fiber and fructooligosaccharide. Twelve female adult beagles were randomly assigned one of the six treatments in a replicated 6x6 Latin square design and fed for 21 d including 17 d of diet adaptation followed by 4 d of total and fresh fecal collection. All diets were well digested by the animals. Dogs fed beet pulp had greater fecal total short-chain fatty acid concentration than the cellulose treatment (P &amp;lt; 0.05), while the dogs fed diets containing miscanthus fiber were intermediate. No difference in the α-diversity of fecal microbial communities was observed among treatments (P &amp;gt;0.05), while β-diversity of dogs fed the beet pulp treatment differed from the other treatment groups. Miscanthus grass can be utilized successfully in diets for adult dogs with tomato pomace and resistant starch blends resulting in similar physiological effects to cellulose.

Network pharmacology-based investigation to explore the effect and mechanism of Erchen decoction against the nonalcoholic fatty liver disease.

This study aimed to uncover the potential mechanism of Erchen decoction (ECD) on the amelioration of nonalcoholic fatty liver disease (NAFLD). Network pharmacology and bioinformatics were used to determine the active components of ECD and its potential target in treating NAFLD. High fat diet (HFD)-induced NAFLD mice model was used. Liver tissues were stained with hematoxylin and eosin, and Oil Red O. Serum lipid profiles and hepatic inflammatory molecules in lipopolysaccharide (LPS)/Toll-like receptor-4 (TLR-4) pathway were confirmed by enzyme-linked immunosorbent assay. Intestinal barrier function, including intestinal epithelial tight junction (IETJ) proteins, fecal short-chain fatty acids (SCFAs) concentration and intestinal microbiota composition, was also assessed. Screening relevant databases revealed 123 active components and 158 potential target proteins in ECD, as well as 1,783 differential genes for NAFLD. Enrichment analyses predicted that the regulation of LPS, cholesterol metabolism and inflammatory pathways might be the underlying mechanisms of ECD in NAFLD treatment. ECD ameliorated the multi-profiles of NAFLD and reversed the high levels of inflammatory molecules such as, serum LPS, hepatic TLR-4, tumor necrosis factor-α, and interleukin-1β. Additionally, ECD upregulated the concentration levels of IETJ proteins and fecal SCFAs. 16s RNA sequencing indicated that ECD can improve the gut microbiota, such as Akkermansia, Clostridium XIVa, Coprococcus, and Ruminococcus. The current study demonstrated that ECD can reverse the HFD-induced intestinal barrier dysfunction, thereby reducing the LPS translocation and alleviating the hepatic inflammation, and eventually exhibiting a protective effect against NAFLD.

Evaluation of the intestinal microbiota and short-chain fatty acids content in patients with chronic inflammatory bowel diseases

Background. The pathogenesis of chronic inflammatory bowel disease (IBD) is still not fully clarified. It is known that disorders of the intestinal microbiota lead to an increased intestinal permeability, activation of mucous and adaptive immunity, impaired production and intestinal absorption of short-chain fatty acids (SCFA). The ratio of acetic, propionic, butyric acids is an important indicator of the integrity of the intestinal microbial community. Thus, the study of the composition of the intestinal microbiota and the concentrations of fecal SCFA is a very promising approach to broadening the understanding of IBD pathogenesis. The purpose of our study was to determine the features of the production of fecal SCFA and the composition of colon microbiota in patients with IBD. Materials and methods. The study, which was carried out at the Department of Intestinal Diseases of the Institute of Gastroenterology of the National Academy of Medical Sciences of Ukraine, involved 74 patients with IBD with an average age of (43.2±1.8) years, who according to nosology were divided into 2 groups: group I— those with ulcerative colitis (UC) (n=66), group II— individuals with Crohn’s disease (CD) (n=8). The diagnoses of CD and UC were established according to generally accepted diagnostic standards in gastroenterology. Determination of fecal SCFA was carried out by chromatographic method with the use of hardware-software complex for medical researches on the basis of the gas chromatographer Chromateс Crystal 5000. The intestinal microflora was evaluated using a microbiological study of the colon content. Results. Patients with IBD had significant changes in the spectrum of SCFA, which were similar in both UC and CD: a decrease in acetic acid in the UC group by 5.7 times, in the CD group by 10.5 times (p&lt;0.05), butyric acid in the UC group by 1.6 times, in the CD group by 1.5 times (p&lt;0.05), and an increase in propionic acid in the UC group by 4 times and in the CD group by 3.3 times (p&lt;0.05) compared with the control group. There was also a significant increase in the anaerobic index in patients with IBD. Microbiological study of feces showed a significant decrease in Lactobacillus, which was observed in all patients with IBD, as well as a decrease in Bifidobacterium in 19.7% of those with UC and in 37.5% with CD. There was a decrease of other representatives of the normal microflora: Enterococci (in 15.2% in the UC group and 25% in the CD group) and Escherichia coli (in 15.2% in the UC group and 12.5% in the CD group). Excessive growth of opportunistic flora was also detected: hemolytic Escherichia coli was increased in 19.7% of patients with UC and in 12.5% of those with CD; Proteus was detected in 12.1% of people with UC and in 37.5% with CD. The excessive growth of Candida was found in 43.9% of patients in the UC group and in 87.5% of individuals with CD. Conclusions. Quantitative and qualitative deviations of the intestinal microbiota, such as a decrease in the number of major symbionts and an increase in the number of opportunistic pathogens, were observed in all examined patients with IBD. The obtained results showed that changes in SCFA concentrations in both nosologies of IBD differed significantly from those in the control group, which in combination with primary genetic defects of the barrier function of the epithelium and its regenerative ability can lead to deterioration in the course and prognosis of IBD. Evaluation of the ratio of SCFA fractions with the calculation of the anaerobic index may be useful for the diagnosis of intestinal dysbiosis in patients with IBD.

Reproducibility, Temporal Variability, and Concordance of Serum and Fecal Bile Acids and Short Chain Fatty Acids in a Population-Based Study.

Bile acid (BA) and short chain fatty acid (SCFA) production is affected by diet and microbial metabolism. These metabolites may play important roles in human carcinogenesis. We used a fully quantitative targeted LC-MS/MS system to measure serum and fecal BA and SCFA concentrations in 136 Costa Rican adults at study baseline and 6-months. We randomly selected 50 participants and measured their baseline samples in duplicate. Our objective was to evaluate: Technical reproducibility; 6-month temporal variability; and concordance between sample type collected from the same individual at approximately the same time. Technical reproducibility was excellent, with intraclass correlation coefficients (ICC) ≥0.83 for all BAs except serum tauroursodeoxycholic acid (ICC = 0.72) and fecal glycolithocholic acid (ICC = 0.66) and ICCs ≥0.81 for all SCFAs except serum 2-methylbutyric acid (ICC = 0.56) and serum isobutyric acid (ICC = 0.64). Temporal variability ICCs were generally low, but several BAs (i.e., deoxycholic, glycoursodeoxycholic, lithocholic, taurocholic, and tauroursodeoxycholic acid) and SCFAs (i.e., 2-methylbutyric, butyric, propionic, and valeric acid) had 6-month ICCs ≥0.44. The highest degree of concordance was observed for secondary and tertiary BAs. Serum and fecal BAs and SCFAs were reproducibly measured. However, 6-month ICCs were generally low, indicating that serial biospecimen collections would increase statistical power in etiologic studies. The low concordance for most serum and fecal metabolites suggests that consideration should be paid to treating these as proxies. Our findings will inform the design and interpretation of future human studies on associations of BAs, SCFAs, and potentially other microbial metabolites, with disease risk.

Ginseng soluble dietary fiber can regulate the intestinal flora structure, promote colon health, affect appetite and glucolipid metabolism in rats

In this study, the effects of ginseng water-soluble dietary fiber (ginseng-SDF) on metabolism, appetite and colon health in rats were investigated. The results showed that ginseng-SDF could improve the glucolipid metabolism, especially in the triglyceride levels. Ginseng-SDF also increased satiety and delayed gastric emptying by regulating the appetite hormone levels as ghrelin, glucagon-like peptide-1, peptide YY, and cholecystokinin. In addition, ginseng-SDF improved intestinal structures and enhanced fecal short-chain fatty acids concentrations (especially acetic acid and butyric acid). More importantly, ginseng-SDF affected the abundance of Firmicutes and Bacteroides, and significantly promoted the proliferation of probiotics and cellulolytic bacteria such as Lactobacillus, Bifidobacterium and Ruminococcus_bromii. Among them, Bifidobacterium pseudolongum, Lactobacillus helveticus and R. bromii were correlated with blood glucose and blood lipid levels. These results suggested that ginseng-SDF could alter the intestinal flora structure, promote colon health, and ultimately have a positive impact on glucolipid metabolism and energy homeostasis.

Impact of the dietary inclusion of dried food residues on the apparent nutrient digestibility and the intestinal microbiota of dogs

ABSTRACT The use of food residues for animal nutrition might imply ecological and economic advantages; however, their effects as a potential ingredient have not yet been evaluated in dogs. In the present study, four diets with 0, 5, 10 and 15% dried food residues (DFR), derived from hotel catering, were fed to 10 healthy adult dogs. At the end of each three-week feeding period, faeces and blood were collected. The apparent nutrient digestibility was calculated by the dietary inclusion of titanium dioxide as an inert marker. The results demonstrated that the apparent crude protein digestibility and ether extract digestibility decreased with increasing amounts of DFR in the diets (p < 0.05). In addition, an increase of the faecal concentrations of acetic acid, propionic acid, n-butyric acid and total short-chain fatty acids (SCFA) was observed (p < 0.05). Faecal ammonium and lactate concentrations, as well as plasma phenol and indole concentrations, were not linearly affected by the dietary inclusion of DFR. The relative abundance of Fusobacteria in the faeces of the dogs decreased, and the relative abundance of Actinobacteria and Bacteroidetes increased with increasing amounts of DFR in the diets (p < 0.05). In conclusion, the DFR seemed to be intensively fermented by the intestinal microbiota of the dogs, as indicated by the increased faecal SCFA concentrations and the shifts in the composition of the faecal microbiota. Dietary inclusion levels of up to 5% can be recommended based on our results, as the observed lower apparent crude protein and ether extract digestibility might limit the use of food residues for dogs at higher amounts.

Reduced fecal short-chain fatty acids in hispanic children with ulcerative colitis.

BackgroundIt is known that patients with ulcerative colitis (UC) have reduced numbers of short‐chain fatty acid (SCFA) producing bacteria and reduced SCFA concentration in feces. There is also evidence that Hispanic patients have increased incidence of UC and increased likelihood of developing disease at a younger age. To understand why this might be, we compared fiber intake and fecal SCFA concentrations in Hispanic children with UC and non‐Hispanic children with UC.MethodsIn this cross‐sectional study conducted at the Children's Hospital of Los Angeles, stool was collected from 22 Hispanic and 31 non‐Hispanic children with UC. SCFAs in the stool were quantified using mass spectrometry. Diet information was collected at the time of stool collection using food frequency questionnaires.ResultsAcetic acid, butyric acid, isovaleric acid, and propionic acid concentrations are significantly lower in Hispanic children with UC compared to age, gender, and disease activity matched non‐Hispanic children with UC (p < 0.001). Butyric acid showed the most significant decrease (p = 1.6e‐7) There was no significant difference in fiber intake between Hispanic and non‐Hispanic children with UC.ConclusionTo our knowledge, this is the first study to find that Hispanic children with UC had further reduced SCFAs, independent of disease activity and fiber intake. It is possible that the reduction in SCFAs is related to the colonic disease in Hispanic patients with UC. This may provide more evidence to support the use of SCFA targeted therapies for UC.

Timing of Tributyrin Supplementation Differentially Modulates Gastrointestinal Inflammation and Gut Microbial Recolonization Following Murine Ileocecal Resection.

Background: Gastrointestinal surgery imparts dramatic and lasting imbalances, or dysbiosis, to the composition of finely tuned microbial ecosystems. The aim of the present study was to use a mouse ileocecal resection (ICR) model to determine if tributyrin (TBT) supplementation could prevent the onset of microbial dysbiosis or alternatively enhance the recovery of the gut microbiota and reduce gastrointestinal inflammation. Methods: Male wild-type (129 s1/SvlmJ) mice aged 8–15 weeks were separated into single cages and randomized 1:1:1:1 to each of the four experimental groups: control (CTR), preoperative TBT supplementation (PRE), postoperative TBT supplementation (POS), and combined pre- and postoperative supplementation (TOT). ICR was performed one week from baseline assessment with mice assessed at 1, 2, 3, and 4 weeks postoperatively. Primary outcomes included evaluating changes to gut microbial communities occurring from ICR to 4 weeks. Results: A total of 34 mice that underwent ICR (CTR n = 9; PRE n = 10; POS n = 9; TOT n = 6) and reached the primary endpoint were included in the analysis. Postoperative TBT supplementation was associated with an increased recolonization and abundance of anaerobic taxa including Bacteroides thetaiotomicorn, Bacteroides caecimuris, Parabacteroides distasonis, and Clostridia. The microbial recolonization of PRE mice was characterized by a bloom of aerotolerant organisms including Staphylococcus, Lactobacillus, Enteroccaceae, and Peptostreptococcacea. PRE mice had a trend towards decreased ileal inflammation as evidenced by decreased levels of IL-1β (p = 0.09), IL-6 (p = 0.03), and TNF-α (p < 0.05) compared with mice receiving TBT postoperatively. In contrast, POS mice had trends towards reduced colonic inflammation demonstrated by decreased levels of IL-6 (p = 0.07) and TNF-α (p = 0.07). These changes occurred in the absence of changes to fecal short-chain fatty acid concentrations or histologic injury scoring. Conclusions: Taken together, the results of our work demonstrate that the timing of tributyrin supplementation differentially modulates gastrointestinal inflammation and gut microbial recolonization following murine ICR.