Fecal Short-chain Fatty Acids Research Articles

Gut microbiota response to consumption of milks fermented with specific strains of Lactococcus lactis with hypocholesterolemic effect

The alteration of structure and function of gut microbiota (dysbiosis) appears to be a major factor associated with metabolic disorders such as dyslipidemia and subsequent development of cardiovascular diseases. However, the consumption of fermented milks is a promising strategy to enhance health and restore the function of gut microbiota; specifically, in individuals with intestinal dysbiosis and hypercholesterolemia. Therefore, the aim of the present study was to evaluate the potential association between gut microbiota and the hypocholesterolemic effect of fermented milks with Lactococcus lactis NRRL B-571 (FM-571), NRRL B-572 (FM-572) and NRRL B-600 (FM-600) in Sprague–Dawley rats. Fermented milks were administered to hypercholesterolemic Sprague–Dawley rats during seven weeks. At the end of the experimental period, fecal and colonic microbiota were characterized using 16S RNA gene sequencing. Also, the short chain fatty acids (SCFAs) content was quantified in feces. Results showed that a high-cholesterol diet (HCD) altered the bacterial community in both fecal and mucosal samples. The consumption of fermented milks, specifically FM-572 promoted changes in the structure (beta diversity) in fecal, but not in mucosal microbiota. The levels of SCFAs in feces were improved after fermented milks consumption. From all SCFAs, butyrate was negatively correlated with total cholesterol, LDL-C (p < 0.05) and positively correlated with HDL-C (p < 0.05). Furthermore, Ruminococcaceae, Lactobacillaceae, Lachnospiraceae and Oscillospiraceae families, were negatively associated with total cholesterol, LDL-C (p < 0.05) and positively associated with HDL-C (p < 0.05). The abundance of these families was increased in groups treated with fermented milks, particularly with FM-572 (p < 0.05). Thus, the in vivo hypocholesterolemic effect after the consumption of milks fermented with Lactococcus lactis strains may be related with the modulation of fecal microbiota associated with the increase of butyrate-producing bacteria. Furthermore, these associations may suggest that butyrate may influence the cholesterol metabolism, resulting in the decreasing cholesterol levels.Graphical

Effect of prebiotic fiber on physical function and gut microbiota in adults, mostly women, with knee osteoarthritis and obesity: a randomized controlled trial.

Obesity is a primary risk factor for knee osteoarthritis (OA). Prebiotics enhance beneficial gut microbes and can reduce body fat and inflammation. Our objective was to examine if a 6-month prebiotic intervention improved physical function in adults with knee osteoarthritis and obesity. We also measured knee pain, body composition, quality of life, gut microbiota, inflammatory markers, and serum metabolomics. Adults (n = 54, mostly women) with co-morbid obesity (BMI > 30kg/m2) and unilateral/bilateral knee OA were randomly assigned to prebiotic (oligofructose-enriched inulin; 16g/day; n = 31) or isocaloric placebo (maltodextrin; n = 21) for 6months. Performance based-tests, knee pain, quality of life, serum metabolomics and inflammatory markers, and fecal microbiota and short-chain fatty acids were assessed. Significant between group differences were detected for the change in timed-up-and-go test, 40m fast paced walk test, and hand grip strength test from baseline that favored prebiotic over placebo. Prebiotic also reduced trunk fat mass (kg) at 6months and trunk fat (%) at 3months compared to placebo. There was a trend (p = 0.059) for reduced knee pain at 6months with prebiotic versus placebo. In gut microbiota analysis, a total of 37 amplicon sequence variants differed between groups. Bifidobacterium abundance was positively correlated with distance walked in the 6-min walk test and hand grip strength. At 6months, there was a significant separation of serum metabolites between groups with upregulation of phenylalanine and tyrosine metabolism with prebiotic. Prebiotics may hold promise for conservative management of knee osteoarthritis in adults with obesity and larger trials are warranted. Clinicaltrials.gov/study/NCT04172688.

Lonicera japonica Thunb. and its characteristic component chlorogenic acid alleviated experimental colitis by promoting Lactobacillus and fecal short‐chain fatty acids production

AbstractUlcerative colitis is intricately linked to intestinal oxidative stress and dysbiosis of the gut microbiota. Lonicera japonica Thunb. (LJ) is a traditional edible and medical flower in China, and chlorogenic acid (CGA) is one of its characteristic components. However, it remains unclear whether gut microbiota plays a role in the therapeutic effects of LJ and GCA on colitis. Here, we first observed that oral administration of LJ and CGA for 3 weeks dramatically promoted the growth of Lactobacillus and fecal short‐chain fatty acids (SCFAs) production in healthy mice. Subsequently, the alleviating effects of LJ and CGA on colitis were explored with a dextran sulfate sodium‐induced colitis mice model. The intervention of LJ and CGA notably alleviated inflammation, intestinal barrier impairment, and oxidative stress in colitis and led to a significant elevation in Lactobacillus and fecal SCFAs. Eventually, the key role of gut microbiota and their metabolites on the therapeutic effects was validated by performing fecal microbiota transplantation and sterile fecal suspensions transplantation from LJ and CGA‐treated healthy mice to colitis mice. Our findings demonstrated that consumption of LJ and CGA could benefit the host both in healthy condition and colitis. The beneficial effects were attributed to the improvement of the endogenous antioxidant system and promotion of the probiotic Lactobacillus and SCFAs production. Our study highlighted the great potential of LJ and CGA to be consumed as functional foods and provided novel mechanisms by which they alleviated colitis.

PSIV-17 Effects of butyrin-based additive supplementation on nursery pig performance, fecal dry matter, serum cytokines, short chain fatty acid production, and serum chemistry

Abstract Two experiments were conducted to determine the effects of butyrin-based feed additives on nursery pig performance, fecal dry matter (DM), serum chemistry, and short chain fatty acid (SCFA) production. In Exp. 1, 250 pigs (initially body weight = 5.6 kg) were randomly allotted to 1 of 5 treatments. There were 5 pigs/pen and 10 replications/treatment. Treatments consisted of a negative control, a positive control, and three diets containing various butyrin-based feed additives. The negative control was a corn-soybean meal-based diet with no antibiotics or pharmacological content of Zn or Cu. The positive control contained 3,000 and 2,000 mg/kg of Zn from ZnO in phase 1 (d 0 to 10) and 2 (d 10 to 24), respectively, 250 mg/kg of Cu from CuSO4 in phase 3 (d 24 to 38), and 55 mg/kg of carbadox (Mecadox; Phibro Animal Health Corp., Teaneck, NJ) across all phases. The butyrin-based feed additives were added at 0.1% to the negative control diet and consisted of monobutyrin, mono-tributyrin, or tributyrin. In Exp. 2, 1,492 pigs (initially 5.1 kg) were randomly allotted to 1 of 4 treatments. There were 26 or 27 pigs/pen and 14 replications/treatment. Treatments were fed over 3 phases consisting of a control diet and 3 diets containing different mono-tributyrin blends. In phase 1 and 2, the control diet contained 55 mg/kg of carbadox and 3,000 and 2,000 mg/kg of Zn from ZnO, respectively. Each feed additive was added at 0.3% to the control diet in phase 1 and 2, and 0.1% in phase 3. Phases 1 and 2 were fed by feed budget of 2.3 and 5.4 kg/pig, respectively, and phase 3 until the completion of the study. Overall, for Exp. 1, pigs fed the positive control had increased (P &amp;lt; 0.05) average daily gain (ADG) and average daily feed intake (ADFI) compared with all other treatments (Table). Pigs fed monobutyrin had decreased (P &amp;lt; 0.05) gain to feed ratio (G:F) compared with all other treatments. On d 24, pigs fed the positive control and mono-tributyrin had increased (P&amp;lt; 0.05) fecal DM compared with pigs fed monobutyrin and tributyrin with the negative control intermediate. On d 38, pigs fed mono-tributyrin had increased (P &amp;lt; 0.05) serum haptoglobin and cecal butyrate concentration compared with pigs fed the positive and negative control, respectively, with other treatments intermediate. For Exp. 2, there were no differences in growth performance throughout the study. On d 10, pigs fed mono-tributyrin blend 3 had increased (P&amp;lt; 0.05) fecal DM compared with mono-tributyrin blend 2 with other treatments intermediate. On d 24 and 42, pigs fed mono-tributyrin blend 1 had the highest (P ≤ 0.012) IL-12 concentration, without significant mean separation on d 24. In summary, butyrin-based feed additives had limited effects on growth performance. However, supplementing butyrin-based feed additives led to alterations in fecal consistency, SCFA production, and serum chemistry.

301 Maxwell Lecture: Bacillus probiotics in nursery pigs: The effects of dose on gut health and performance

Abstract Weaning is one of the most stressful events in the life of a pig and critical for their health and development. To reduce the use of antibiotics and zinc oxide in nursery diets, many feed additives have been tested to demonstrate their efficacy in weaning pigs. Bacillus subtilis, a heat-resistant spore-forming bacteria, consumes oxygen in the digestive tract and can provide a favorable anaerobic environment for lactic acid-producing bacteria, resulting in their proliferation. It also produces several digestive enzymes, such as amylase, protease, and antioxidant enzymes. In addition, Bacillus species are known to alter the gut microbiome and increase the production of short-chain fatty acids in the gut. Therefore, Bacillus probiotics have been widely used in nursery diets to effectively improve growth performance and protect piglets from weaning stress and postweaning diarrhea. However, when the probiotics are supplemented in diets for weaning pigs, their efficacy is dependent on multiple factors, such as strains, the health condition of the animals, product composition, and the dose of the probiotics. There has been tremendous effort in establishing the optimal supplementation level of probiotics for nursery pigs to maximize the efficacy of their supplementation, but a high dose of probiotics could be detrimental to the gut health and microflora of nursery pigs, as it could increase the incidence of diarrhea and may have potential side effects in the immune system, antibiotic resistance, and the production of unfavorable metabolites in the gut. A study was conducted to demonstrate the effect of Bacillus probiotic supplementation for nursery pigs at the recommended and high doses (10 times greater bacterial counts than the recommended dose) compared with a control treatment with no probiotic supplementation. In the study, the Bacillus supplementation at the recommended dose did improve the early postweaning growth rate, increase the production of fecal short-chain fatty acids (acetate, propionate, and butyrate), and blood glucose concentrations, and alter the fecal microbiome. However, high-dosing probiotics in nursery diets did not show any beneficial effects that were shown in the pigs fed diets with Bacillus probiotics at the recommended dose. Bacillus-probiotic supplementation in nursery diets may enhance growth performance and benefit gut health, but a high dose of probiotics does not always lead to comparable positive effects for pigs. Therefore, it is critically important to test probiotics to optimize their efficacy and avoid unnecessary high-dosing in nursery diets, as it could be cost-ineffective and may not show benefits that can be observed with the recommended dose.

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 ± 45.9µM, 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.

Polysaccharides of Aspergillus cristatus attenuate obesity by regulating gut microbiota and gut microbiota-related metabolites

Golden-flower fungus, the only dominant microorganism determining the Fu-brick tea quality through fermentation and the important microbe in Liupao tea, is considered a potential probiotic fungus based on its anti-obesity effect. However, the classification of golden-flower fungi is still controversial; the anti-obesity effect of golden-flower fungus polysaccharides remains unknown. In this study, we identify a golden-flower strain as Aspergillus cristatus based on morphological characteristics and multigene phylogeny analysis, which resolves the controversy of classification. Moreover, we find A. cristatus polysaccharides (ACPS) attenuate obesity in rats. ACPS modulate gut bacterial composition, in which Akkermansia, Akkermansia muciniphila, Bacteroides, Romboutsia, Blautia, and Desulfovibrio are considered the core microbes regulated by ACPS. ACPS increase fecal total short-chain fatty acid content and serum, hepatic, and fecal total bile acid content. Furthermore, ACPS-induced gut microbiota alteration plays a causal role in the protection from obesity, according to a fecal transplantation experiment. Thus, ACPS ameliorate obesity by regulating gut microbiota and gut microbiota-related metabolites.

Effect of Miscellaneous Meals Replacing Soybean Meal in Feed on Growth Performance, Serum Biochemical Parameters, and Microbiota Composition of 25-50 kg Growing Pigs.

The present study aims to determine the effect of miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower meal) replacing soybean meal in feed on growth performance, apparent digestibility of nutrients, serum biochemical parameters, serum free amino acid content, microbiota composition and SCFAs content in growing pigs (25-50 kg). A total of 72 (Duroc × Landrace × Yorkshire) growing pigs with initial weights of 25.79 ± 0.23 kg were randomly divided into three treatments. The pigs were fed corn-soybean meal (CON), corn-soybean-miscellaneous meals (CSM), and corn-miscellaneous meals (CMM). Each treatment included six replicates with four pigs per pen (n = 24, 12 barrows and 12 gilts). Soybean meal accounted for 22.10% of the basal diet in the CON group. In the CSM group, miscellaneous meals partially replaced soybean meal with a mixture of 4.50% rapeseed meal, 3.98% cottonseed meal, and 4.50% sunflower meal. In the CMM group, miscellaneous meals entirely replaced soybean meal with a mixture of 8.50% rapeseed meal, 8.62% cottonseed meal, and 8.5% sunflower. The results showed that compared with the CON, the CSM and CMM groups significantly improved the average daily gain (ADG) of growing pigs during the 25-50 kg stage (p < 0.05) but had no effects on average daily feed intake (ADFI) and average daily feed intake/average daily gain (F/G) (p > 0.05). Moreover, the CMM group significantly reduced nutrient apparent digestibility of gross energy compared with the CON group. The serum biochemical parameters results showed that the CSM group significantly improved the contents of total protein (TP) compared with the CON group (p < 0.05). The CMM group significantly improved the contents of total protein (TP), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) compared with the CON group in serum (p < 0.05). In comparison with the CON group, the CMM group also significantly improved lysine (Lys), threonine (Thr), valine (Val), isoleucine (Ile), leucine (Leu), phenylalanine (Phe), arginine (Arg), and citrulline (Cit) levels in serum (p < 0.05). However, the CMM group significantly decreased non-essential amino acid content glycine (Gly) in serum compared with CON (p < 0.05), while compared with the CON group, the CSM and CMM groups had no significant effects on the relative abundance, the alpha-diversity, or the beta-diversity of fecal microbiota. Moreover, compared with the CON group, the CSM group significantly increased butyric acid and valeric acid contents of short-chain fatty acids (SCFAs) in feces (p < 0.05). In contrast to the CON group, the CMM group significantly reduced the contents of SCFAs in feces, including acetic acid, propionic acid, and isobutyric acid (p < 0.05). Collectively, the results of the present study indicate that miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower meal) can partially replace the soybean meal and significantly improve the growth performance of growing pigs during the 25-50 kg stage. Thus, miscellaneous meals are a suitable protein source as basal diets to replace soybean meals for 25-50 kg growing pigs. These results can be helpful to further develop miscellaneous meals as a functional alternative feed ingredient to soybean meal.

Effects of Multi-species Synbiotic Supplementation on Circulating miR-27a, miR-33a Levels, and Lipid Parameters in Adult Men with Dyslipidemia; A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

MicroRNAs (miRNAs) have emerged as important regulators of lipid metabolism. Recent studies have suggested synbiotics may modulate miRNA expression and lipid metabolism. This study aimed to investigate the effects of synbiotic supplementation on circulating miR-27a, miR-33a, and lipid parameters in patients with dyslipidemia. Fifty-six eligible participants were randomly allocated to receive either synbiotic or placebo sachets twice a day for 12 weeks. Each synbiotic sachet contained 3×1010 CFU six species of probiotic microorganisms and 5 grams of inulin and fructooligosaccharide (FOS) as prebiotics. Serum miR-27a and miR-33a expression levels, serum lipids, and apolipoproteins, the fecal concentration of short-chain fatty acids (SCFAs), and Firmicutes and Bacteroidetes phyla were assessed before and after the study. Real-time PCR was used to determine the relative expression levels of miRNAs. The results showed synbiotic supplementation significantly downregulated the expression levels of miR-27a and miR-33a compared to the placebo group (p = 0.008 and p = 0.001, respectively). Furthermore, the intervention group exhibited significant improvements in serum high-density lipoprotein (HDL-C), small dense low-density lipoprotein (sdLDL-C), apoA-I, and apoB-100 (p = 0.008, p = 0.006, p = 0.003, p = 0.001, respectively). The results showed a significant negative correlation between miR-33a expression levels with HDL-C, butyrate, propionate, and a significant positive correlation with total cholesterol (TC), low-density lipoprotein (LDL-C), and sdLDL-C in the intervention group. Fecal bacteria and SCFAs were significantly increased in the intervention group. This study provides evidence that synbiotic supplementation can modulate miR-27a and miR-33a expression and improve lipid metabolism in patients with dyslipidemia.

A metagenomic approach to unveil the association between fecal gut microbiota and short-chain fatty acids in diarrhea caused by diarrheagenic Escherichia coli in children

Diarrheagenic Escherichia coli (DEC) is the main cause of diarrhea in children under five years old. The virulence of DEC is tightly regulated by environmental signals influenced by the gut microbiota and its metabolites. Short-chain fatty acids (SCFAs) are the main metabolic product of anaerobic fermentation in the gut, but their role in DEC diarrhea has not yet been established. In this study, we determine the levels of acetate, propionate, and butyrate in stool samples from children with diarrhea caused by DEC, and we identify bacteria from the fecal gut microbiota associated with the production of SCFAs. The microbiota and SCFAs levels in stool samples obtained from 40 children with diarrhea and 43 healthy children were determined by 16S rRNA gene sequencing and HPLC, respectively. Additionally, shotgun metagenomics was used to identify metagenome-assembled genomes (MAGs) in a subgroup of samples. The results showed significantly higher levels of all SCFAs tested in diarrheal samples than in healthy controls. The abundance of Streptococcus sp., Limosilactobacillus, Blautia, Escherichia, Bacteroides, Megamonas, and Roseburia was higher in the DEC group than in healthy individuals. Functional analysis of bacteria and their main metabolic pathways made it possible to identify species MAGs that could be responsible for the detected SCFAs levels in DEC-positive diarrhea. In conclusion, based on our results and published data, we suggest that SCFAs may be important in the crosstalk between the microbiota and DEC pathogens in the gut.

Defatted black soldier fly larvae meal in lactating sow and pre-weaning piglet diets: impacts on growth performance, fecal microbiota, and metabolic pathways

Abstract To address the underexplored use of black soldier fly larval (BSFL) meal in pig farming for sustainable development, this study examined the effects of substituting conventional protein with defatted BSFL meal in the pre-weaning diet of piglets farrowed from sows fed defatted BSFL diets (0%, 2.3%, and 4.6%). Fifty-four piglets (18 piglets in each treatment) were housed with sows until 28 days of age and fed a pre-weaning diet containing 0%, 12.5%, or 25% defatted BSFL meal based on their respective sows’ dietary treatments (0%, 2.3%, and 4.6% defatted BSFL diets) from 21 to 35 days of age. The growth performances and fecal microbiota of piglets were investigated. The results showed that sow diets and defatted BSFL meal-incorporated pre-weaning diets did not have a significant effect on the growth performance of piglets (). However, piglet growth tended to decrease with increasing defatted BSFL meals in the pre-weaning diets. Additionally, piglets nursed by sows fed defatted BSFL diets showed higher fecal short-chain fatty acid and lower ammonia levels at 21 days of age than those nursed by sows fed a control diet (). Furthermore, defatted BSFL meal-incorporated pre-starter diets decreased fecal amino acids and modified the gut microbial metabolic pathways associated with stress response. These findings suggest that the appropriate inclusion of defatted BSFL meal in the diets of lactating sows and piglets did not adversely affect the growth performance of piglets and may potentially improve the health of piglets at weaning; however, attention should be paid to the chitin content in BSFL diets, which may affect nutrient digestibility. Incorporating 2.3% defatted BSFL to sow and 12.5% to pre-weaning piglet diets may serve as a feeding strategy in pig farming. The results obtained will aid the application of BSFL meal in the swine industry and the study of its dietary effect on weaning stress in piglets.

A Two-Faced Gut Microbiome: Butyrogenic and Proinflammatory Bacteria Predominate in the Intestinal Milieu of People Living with HIV from Western Mexico.

HIV infection results in marked alterations in the gut microbiota (GM), such as the loss of microbial diversity and different taxonomic and metabolic profiles. Despite antiretroviral therapy (ART) partially ablating gastrointestinal alterations, the taxonomic profile after successful new ART has shown wide variations. Our objective was to determine the GM composition and functions in people living with HIV (PLWHIV) under ART in comparison to seronegative controls (SC). Fecal samples from 21 subjects (treated with integrase strand-transfer inhibitors, INSTIs) and 18 SC were included. We employed 16S rRNA amplicon sequencing, coupled with PICRUSt2 and fecal short-chain fatty acid (SCFA) quantification by gas chromatography. The INSTI group showed a decreased α-diversity (p < 0.001) compared to the SC group, at the expense of increased amounts of Pseudomonadota (Proteobacteria), Segatella copri, Lactobacillus, and Gram-negative bacteria. Concurrently, we observed an enrichment in Megasphaera and Butyricicoccus, both SCFA-producing bacteria, and significant elevations in fecal butyrate in this group (p < 0.001). Interestingly, gut dysbiosis in PLWHIV was characterized by a proinflammatory environment orchestrated by Pseudomonadota and elevated levels of butyrate associated with bacterial metabolic pathways, as well as the evident presence of butyrogenic bacteria. The role of this unique GM in PLWHIV should be evaluated, as well as the use of butyrate-based supplements and ART regimens that contain succinate, such as tenofovir disoproxil succinate. This mixed profile is described for the first time in PLWHIV from Mexico.

L-Glutamine Substantially Improves 5-Fluorouracil-Induced Intestinal Mucositis by Modulating Gut Microbiota and Maintaining the Integrity of the Gut Barrier in Mice.

This study investigates the potential of glutamine to mitigate intestinal mucositis and dysbiosis caused by the chemotherapeutic agent 5-fluorouracil (5-FU). Over twelve days, Institute of Cancer Research (ICR) mice are given low (0.5 mgkg-1) or high (2 mgkg-1) doses of L-Glutamine daily, with 5-FU (50 mgkg-1) administered between days six and nine. Mice receiving only 5-FU exhibited weight loss, diarrhea, abnormal cell growth, and colonic inflammation, correlated with decreased mucin proteins, increased endotoxins, reduced fecal short-chain fatty acids, and altered gut microbiota. Glutamine supplementation counteracted these effects by inhibiting the Toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) pathway, modulating nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) oxidative stress proteins, and increasing mammalian target of rapamycin (mTOR) levels, thereby enhancing microbial diversity and protecting intestinal mucosa. These findings underscore glutamine's potential in preventing 5-FU-induced mucositis by modulating gut microbiota and inflammation pathways.

Effect of Stool Sampling on a Routine Clinical Method for the Quantification of Six Short Chain Fatty Acids in Stool Using Gas Chromatography-Mass Spectrometry.

Short chain fatty acids (SCFAs) are primarily produced in the caecum and proximal colon via the bacterial fermentation of undigested carbohydrates that have avoided digestion in the small intestine. Increasing evidence supports the critical role that SCFAs play in health and homeostasis. Microbial SCFAs, namely butyric acid, serve as a principal energy source for colonocytes, and their production is essential for gut integrity. A direct link between SCFAs and some human pathological conditions, such as inflammatory bowel disease, irritable bowel syndrome, diarrhea, and cancer, has been proposed. The direct measurement of SCFAs in feces provides a non-invasive approach to demonstrating connections between SCFAs, microbiota, and metabolic diseases to estimate their potential applicability as meaningful biomarkers of intestinal health. This study aimed to adapt a robust analytical method (liquid-liquid extraction, followed by isobutyl chloroformate derivatization and GC-MS analysis), with comparable performances to methods from the literature, and to use this tool to tackle the question of pre-analytical conditions, namely stool processing. We focused on the methodology of managing stool samples before the analysis (fresh stool or dilution in either ethanol/methanol, lyophilized stool, or RNAlater®), as this is a significant issue to consider for standardizing results between clinical laboratories. The objective was to standardize methods for future applications as diagnostic tools. In this paper, we propose a validated GC-MS method for SCFA quantification in stool samples, including pre- and post-analytical comparison studies that could be easily used for clinical laboratory purposes. Our results show that using lyophilization as a stool-processing method would be the best method to achieve this goal.

The Changes in Fecal Bacterial Communities in Goats Offered Rumen-Protected Fat.

Leizhou goats are famous for their delicious meat but have inferior growth performance. There is little information on rumen-protected fat (RPF) from the Leizhou goat. Hence, we observed the effects of RPF on growth, fecal short-chain fatty acids, and bacteria community with respect to Leizhou goats. Twelve goats (13.34 ± 0.024 kg) were selected and assigned randomly to one of two treatments: (1) a control diet (CON) and (2) 2.4% RPF with a control diet (RPF). The final body weight and average daily gain (ADG) were greater (p < 0.05), and the dry matter intake (DMI): ADG was lower (p < 0.05) in the RPF group than in the CON group. There were no differences in DMI between the CON and RPF groups. The concentrations of total short-chain fatty acids, acetate, propionate, and butyrate were lower (p < 0.05) in the RPF group than in the CON group. The relative abundances of Ruminococcus, Rikenellaceae_RC9_gut_group, Treponema, norank_f__norank_o__RF39, Eubacterium_siraeum_group, and Ruminococcus_torques_group were lower (p < 0.05) in the RPF group than in the CON group. The relative abundances of Bacteroides, norank_f__norank_o__Clostridia_UCG-014, norank_f__Eubacterium_coprostanoligenes_group, Eubacterium_ruminantium_group, norank_f__Oscillospirale-UCG-010, Oscillospiraceae_UCG-002, and Family_XIII_AD3011_group were greater (p < 0.05) in the RPF group than in the CON group. It was concluded that RPF could improve the goats' growth performance by regulating their fecal bacteria communities.

No Impact of Enteral Nutrition on Fecal Short-Chain Fatty Acids in Children with Cerebral Palsy.

Bacteria can impact the host organism through their metabolites, with short-chain fatty acids (SCFAs) being the most important, including acetate (C2), propionate (C3), butyrate (C4), valerate (C5n), and isovalerate (C5i). This study aimed to identify the impact of enteral nutrition on SCFAs in children with cerebral palsy and to test the hypothesis that the type of nutrition in cerebral palsy affects gut SCFA levels. Cerebral palsy is a heterogeneous syndrome resulting from non-progressive damage to the central nervous system. The study group included 30 children diagnosed with cerebral palsy, receiving enteral nutrition (Cerebral Palsy Enteral Nutrition (CPEN)) via gastrostomy. The first reference group (Cerebral Palsy Controls (CPCs)) consisted of 24 children diagnosed with cerebral palsy and fed orally on a regular diet. The second reference group (Healthy Controls (HCs)) consisted of 24 healthy children with no chronic disease and fed on a regular diet. Isolation and measurement of SCFAs were conducted using gas chromatography. Differences were observed in the median contents of isobutyric acid, valeric acid, and isovaleric acid between the CPC group, which had significantly higher levels of those acids than the HC group. No differences were found between the CPEN and CPC groups nor between the CPEN and HC groups. We conclude that enteral nutrition in cerebral palsy has no influence on the levels of SCFAs.

Evaluation of Menopausal Syndrome Relief and Anti-Obesity Efficacy of the Korean Fermented Food Doenjang: A Randomized, Double-Blind Clinical Trial.

Foods that help improve menopausal syndrome are being studied worldwide. Doenjang is a traditional Korean fermented soybean food with potential health benefits for menopausal women. In this clinical trial using Doenjang, we aimed to compare the effectiveness of traditional Doenjang and commercial Doenjang in menopausal women. Furthermore, we compared whether Doenjang has a better effect if the number of beneficial microbes is higher. The analyses included the following groups: traditional Doenjang containing either a high dose (HDC; n = 18) or low dose (LDC; n = 18) of beneficial microbes and commercial Doenjang (CD; n = 20). The Kupperman index and hematological changes were examined before and after the use of Doenjang pills. The effects of Doenjang on obesity and body composition were studied before and after ingestion. Lastly, the microorganisms and short-chain fatty acid changes in the stool were compared. The Kupperman index decreased after Doenjang consumption in all three groups, with the greatest decrease in the LDC group. Only the groups that took traditional Doenjang pills exhibited reduced LDL cholesterol. No changes in obesity and inflammation-related indicators were observed. The number of Firmicutes, associated with obesity, decreased in the CD group but the numbers of Bacteroidetes increased in the HDC and CD groups. Thus, traditional Doenjang is more effective in alleviating menopausal syndrome than commercial Doenjang. Further research on the anti-obesity effect or changes in microbiomes and short-chain fatty acids in feces is needed.

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).

Disordered GPR43/NLRP3 expression in peripheral leukocytes of patients with atrial fibrillation is associated with intestinal short chain fatty acids levels

BackgroundAtrial fibrillation (AF) is associated with circulating inflammation. Short-chain fatty acids (SCFAs) derived from gut microbiota (GM) regulate leukocyte function and inhibit the release of inflammatory cytokines, which are partly mediated by the G-protein-coupled receptor 43 (GPR43) signaling. This study aimed to investigate the expression of GPR43/NOD-like receptors family pyrin domain containing 3 (NLRP3) in leukocytes and the interaction with intestinal SCFAs levels in AF patients.MethodsExpressions of GPR43 and NLRP3 mRNA in peripheral blood leukocytes from 23 AF patients and 25 non-AF controls were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Expressions of leukocyte GPR43 and NLRP3 protein were evaluated by western blot analysis. The levels of plasma IL-1β were measured by enzyme-linked immunosorbent assay (ELISA). The fecal SCFAs levels based on GC/MS metabolome of corresponding 21 controls and 14 AF patients were acquired from our published dataset. To evaluate the expression of NLRP3 and GPR43 and the release of IL-1β, human THP-1 cells were stimulated with or without SCFAs (acetate, propionate, and butyrate), lipopolysaccharide (LPS), and nigericin in vitro, respectively.ResultsCompared to the controls, the mRNA expression in peripheral leukocytes was significantly reduced in AF patients (P = 0.011) coupled with the increase in downstream leukocyte NLRP3 mRNA expression (P = 0.007) and plasma IL-1β levels (P < 0.001), consistent with changes in GPR43 and NLRP3 protein expression. Furthermore, leukocyte GPR43 mRNA levels were positively correlated with fecal GM-derived acetic acid (P = 0.046) and negatively correlated with NLRP3 mRNA expression (P = 0.024). In contrast to the negative correlation between left atrial diameter (LAD) and GPR43 (P = 0.008), LAD was positively correlated with the leukocyte NLRP3 mRNA levels (P = 0.024). Subsequent mediation analysis showed that 68.88% of the total effect of intestinal acetic acid on AF might be mediated by leukocyte GPR43/NLRP3. The constructed GPR43–NLRP3 score might have a predictive potential for AF detection (AUC = 0.81, P < 0.001). Moreover, SCFAs treatment increased GPR43 expression and remarkably reduced LPS/nigericin-induced NLRP3 expression and IL-1β release in human THP-1 cells in vitro.ConclusionsDisrupted interactions between GPR43 and NLRP3 expression in peripheral blood leukocytes, associated with reduced intestinal GM-derived SCFAs, especially acetic acid, may be involved in AF development and left atrial enlargement by enhancing circulating inflammation.

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.