Oscillospira - a candidate for the next-generation probiotics

Structural characteristics and nonvolatile metabolites of theabrownins and their impact on intestinal microbiota in high-fat-diet-fed mice

This study prepared enzymatic theabrownins (TBs-e), alkaline theabrownins (TBs-a), and Pu-erh tea theabrownins (TBs-f), and investigated whether different preparation processes affected the structures, nonvolatile metabolites, and biofunctional activities of TBs. Structural characterization revealed that TBs were polymeric phenolic compounds rich in hydroxyl and carboxyl groups. Nontargeted metabolomics revealed that amino acids were the primary nonvolatile metabolites in TBs-e and TBs-a, accounting for over 70 % of the total nonvolatile content. TBs-f contained more polyphenols, caffeine, and flavonoids, accounting for 14.2 %, 3.9 %, and 0.8 % of total nonvolatile content, respectively. In vivo, at 560 mg/kg body weight, TBs-f were associated with regulation of blood glucose and lipid concentrations in mice. Moreover, 16S rRNA indicated that at 1120 mg/kg body weight, TBs-a were associated with increased numbers of microbiota linked with hypolipidemic activity. This study explores the impacts of different preparation processes on TBs and provides a theoretical foundation for the understanding of TBs.

Preventive and therapeutic effects of molecular iodine in a model of diabetes mellitus induced by streptozotocin

Diabetes mellitus (DM) is a multifactorial condition that involves oxidative alterations and dysbiosis of the gut microbiota associated with an imbalance in glucose metabolism. Therefore, the need to develop integrative therapies that are both effective and have fewer side effects has become evident in recent years. Molecular iodine (I2) has antioxidant effects in preclinical hyperglycemic models. The present work analyzes the preventive and therapeutic effects of oral I2 supplementation in a DM model induced by low doses of streptozotocin (STZ). Male CD1 mice (12 weeks old) were divided into the following groups: control, STZ (20 mg/kg/day, i.p., for 5 days), I2 (0.2 mg/Kg in drinking water), preventive (STZ + I2), and therapeutic (I2 supplementation from day 35 to day 90; STZ + I2(Ther)). The supplementation with I2 prevented and normalized hyperglycemia, hypercholesterolemia, and hypertriglyceridemia associated with STZ, preserving pancreatic, liver, muscle, and adipose tissue morphology and normalizing inflammatory gene induction (TLR2, TLR4, NFkβ, TNFα) in several tissues. Furthermore, compared to the STZ group, the presence of I2 favored a more significant abundance of beneficial bacteria that support the integrity of the intestinal epithelial barrier and higher α-diversity. In conclusion, the I2 supplement has preventive and therapeutic effects, reducing oxidative damage and reestablishing microbiota diversity following STZ exposure.

Structural characterization and hypolipidemic activity of a hetero-galactan purified from Sanghuangporus vaninii based on modulation of TLR4/NF-κB pathway

Sanghuangporus vaninii showed great activities of anti-inflammation and anti-tumor, due to its bioactive macromolecules. However, the hypolipidemic properties of polysaccharides isolated from S. vaninii have not been systematically reported. In this research, a polysaccharide of S. vaninii was obtained and its hypolipidemic activity was investigated. SVP3, a neutral hetero-galactan from S. vaninii, has a →6)-α-Galp-(1→ backbone with partial H-2 branches of α-Manp-(1→ or α-Manp-(1→2)-α-Fucp-(1→. In a hyperlipidemia mouse model, SVP3 significantly inhibited body weight gain and suppressed serum levels of total cholesterol, triglycerides, and low-density lipoprotein cholesterol. SVP3 inhibited the expansion of adipocytes in three types of white adipose tissues and attenuated hepatic injury and hepatic lipid deposition in the mice. The combined analysis of gut microbiota, serum metabolomics, and liver proteomics revealed that SVP3 effectively regulated the abundance of specific gut microbiota and serum metabolites and mediated the inhibitory effect on inflammation-associated toll-like receptor 4/nuclear factor kappa-B pathway by regulating the expression levels of glutathione S-transferase P1, stromal cell derived factor 2-like 1, ribosomal protein L10, thiosulfate sulfurtransferase, and biliverdin reductase A in liver, ultimately realizing the hypolipidemic activity. The results of the present study provide experimental evidence for the development of clinical adjuvant therapeutic drugs to treat hyperlipidemia.

Unravelling metabolite-microbiome interactions in inflammatory bowel disease through AI and interaction-based modelling

Inflammatory Bowel Diseases (IBDs) are chronic inflammatory disorders of the gastrointestinal tract and colon affecting approximately 7 million individuals worldwide. The knowledge of specific pathology and aetiological mechanisms leading to IBD is limited, however a reduced immune system, antibiotic use and reserved diet may initiate symptoms. Dysbiosis of the gut microbiome, and consequently a varied composition of the metabolome, has been extensively linked to these risk factors and IBD. Metagenomic sequencing and liquid-chromatography mass spectrometry (LC-MS) of N = 220 fecal samples by Fransoza et al., provided abundance data on microbial genera and metabolites for use in this study. Identification of differentially abundant microbes and metabolites was performed using a Wilcoxon test, followed by feature selection of random forest (RF), gradient-boosting (XGBoost) and least absolute shrinkage operator (LASSO) models. The performance of these features was then validated using RF models on the Human Microbiome Project 2 (HMP2) dataset and a microbial community (MICOM) model was utilised to predict and interpret the interactions between key microbes and metabolites. The Flavronifractor genus and microbes of the families Lachnospiraceae and Oscillospiraceae were found differential by all models. Metabolic pathways commonly influenced by such microbes in IBD were CoA biosynthesis, bile acid metabolism and amino acid production and degradation. This study highlights distinct interactive microbiome and metabolome profiles within IBD and the highly potential pathways causing disease pathology. It therefore paves way for future investigation into new therapeutic targets and non-invasive diagnostic tools for IBD.

Functional Modulation of Gut Microbiota and Blood Parameters in Diabetic Rats Following Dietary Intervention with Free or Immobilized Pediococcus acidilactici SK Cells on Pistachio Nuts

BACKGROUND/OBJECTIVES

The gut microbiota is linked to the pathogenesis of type 1 diabetes mellitus (T1DM), while supplementation with probiotics may result in positive alterations in the composition of the gut microbiome. This research aimed to map the changes in the gut microbiome and blood markers of streptozotocin-induced diabetic rats after a dietary intervention with free or immobilized cells of the presumptive probiotic Pediococcus acidilactici SK on pistachio nuts.

METHODS

Twenty-four male Wistar rats were studied and divided into four groups (healthy or diabetic) which received the free or the immobilized P. acidilactici SK cells on pistachio nuts for 4 weeks. Blood, fecal, and intestinal tissue samples were examined.

RESULTS

The diabetic rats exhibited an elevated concentration of HDL-c, while the inflammatory IL-1β levels were significantly lower in the diabetic animals that received the immobilized cells compared to the group that received the free cells. The dietary intervention with immobilized cells led to decreased counts of fecal staphylococci and enterococci in the diabetic animals, while the diet with both free and immobilized P. acidilactici SK cells rendered levels of these populations in normal values in the feces and intestinal tissue of the diabetic animals. Noticeably, the Lactobacillus and Bifidobacterium genera were elevated after the supplementation with immobilized P. acidilactici SK cells on pistachio nuts.

CONCLUSIONS

Dietary supplementation with P. acidilactici SK cells (in free or in immobilized form) beneficially affected the gut microbiota/microbiome of streptozotocin-induced diabetic rats, leading to the alleviation of dysbiosis and inflammation and control over their lipid levels.

Polypeptide of Inonotus hispidus extracts alleviates periodontitis through suppressing inflammatory bone loss

This study aimed to characterize and evaluate the effects of a novel polypeptide isolated from Inonotus hispidus (IH) against periodontitis. The polypeptides extracted and purified from the fruiting body of IH had a uniform molar mass, including 23 types of peptides. IH polypeptide (IHP) exerted antimicrobial activity against Porphyromonas gingivalis (P. gingivalis) by damaging the cell walls and membranes of microorganisms, disturbing energy metabolism, and regulating the expression of virulence factors. IHP significantly inhibited inflammation in lipopolysaccharides (LPS)-stimulated Raw264.7 cells evidenced by the regulation of inflammatory cytokine levels. In rats with ligature-induced periodontitis, IHP treatment ameliorated alveolar bone destruction and preserved the balance between oral flora and gut microbes. The interaction between oral and intestinal flora possibly affected the relevant metabolites. Proteomics combined with confirmation experiment revealed that the β-catenin/ nuclear factor-kappa B (NF-κB) signaling may be involved in IHP-mediated anti-periodontitis in rats, which helps reduce the secretion of pro-inflammatory factors and inhibit inflammatory osteoclastic response in the periodontal tissue. Additionally, IHP improved clinical parameters, including the plaque index (PLI), pocket depth (PD), bleeding on probing (BOP), and average probing depth in individuals with periodontitis. These findings augment the understanding of the potential role of IHP in treating periodontitis.

Oral supplementation with lactic acid bacteria improve the intestinal epithelial barrier and gut microbiota of broiler chicks to alleviate Salmonella Enteritidis infection

Lactic acid bacteria (LAB) play a key role in regulating the balance of gut microbiota and serve as a suitable alternative to antibiotics. This study aims to evaluate the characteristics of 2 LAB isolates Lactiplantibacillus plantarum Lp71 (L. plantarum Lp71) and Enterococcus faecium Ef72 (E. faecium Ef72), and their roles in alleviating Salmonella Enteritidis infection. Sixty 1-day-old chicks were randomly divided into 4 groups which treated with or without L. plantarum Lp71 and E. faecium Ef72 mixture for 21 d, and then intestinal samples were collected for gut microbiota analysis, pathological and immunohistochemical analysis at 24 h post infection with or without Salmonella Enteritidis on the 22nd d. The results showed that L. plantarum Lp71 and E. faecium Ef72 had the ability to anti-acid and anti-bile salt. Salmonella Enteritidis infection damaged the intestinal epithelial barrier and reduced the expression level of tight junction proteins (ZO-1, Claudin-1, Occludin). Oral supplementation with L. plantarum Lp71 and E. faecium Ef72 mixture could alleviated the damages to intestinal epithelial barrier by Salmonella Enteritidis infection. Salmonella Enteritidis could cause abnormal Akkermansia muciniphila proliferation and decrease the diversity of cecal microbiota in chicks. These conditions could have further led to reduce gut microbiota health index (GMHI), and improve microbial dysbiosis index (MDI). Moreover, oral supplementation with L. plantarum Lp71 and E. faecium Ef72 mixture could effectively prevent the aforementioned infection outcomes and increase the abundance proportions of the several key functions in metabolic pathways metabolic pathways such as transcription and signal transduction mechanisms. In summary, L. plantarum Lp71 and E. faecium Ef72 could be the probiotics candidates that used to prevent the damage from enteric pathogens such as Salmonella Enteritidis in broiler chicks.

Beetroot juice intake positively influenced gut microbiota and inflammation but failed to improve functional outcomes in adults with long COVID: A pilot randomized controlled trial

BACKGROUND & AIMS

Long-term effects of coronavirus disease 2019 (long COVID) develop in a substantial number of people following an acute COVID-19 episode. Red beetroot juice may have positive effects on multiple pathways involved in long COVID. The aim of this pilot study was to explore the impact of beetroot juice supplementation on physical function, gut microbiota, and systemic inflammation in adults with long COVID.

METHODS

A single-center, double-blind, placebo-controlled randomized trial was conducted to test the effects of 14 days of beetroot juice supplementation, rich in nitrates and betalains, on functional and biological outcomes in adults aged between 20 and 60 years with long COVID. Participants were randomized 1:1 to receive either daily oral supplementation with 200 mL beetroot juice (∼600 mg nitrate) or placebo (∼60 mg nitrate) for 14 days. The primary endpoint was the change from baseline to day 14 in a fatigue resistance test. Secondary outcomes included the distance walked on the 6-min walk test, handgrip strength, and flow-mediated dilation. Secondary endpoints also included changes from baseline in circulating inflammatory mediators and metagenomic and fecal water metabolomic profiles. Partial least squares discriminant analysis (PLS-DA) models were built to evaluate the differences in biological variables associated with the interventions.

RESULTS

Thirty-one participants were randomized in the study. Twenty-five of them (median (interquartile range) age 40 (10), 14 [56 %] women), received either beetroot juice (15) or placebo (10) and completed the study. At 14 days, fatigue resistance significantly improved from baseline (mean difference [standard error]: +21.8 [3.7] s; p < 0.001) with no significant differences between intervention groups. A significant increase from baseline in the distance walked on the 6-min walk test was observed (mean difference [standard error]: +30.0 [9.4] m; p = 0.03), which was not different between groups. Flow-mediated dilation did not differ between participants who received beetroot juice and those on placebo. PLS-DA models allowed correct classification of participants with 92.2 ± 4.4 % accuracy. Those who ingested red beetroot juice had a greater abundance of bacteria with well-known beneficial effects, including Akkermansia, Oscillospira, Prevotella, Roseburia, Ruminococcaceae, and Turicibacter, compared with placebo. Participants allocated to beetroot juice supplementation were also characterized by significantly higher levels of fecal nicotinate, trimethylamine, and markers of beetroot juice intake (e.g., 5,6-dihydroxyindole). Finally, higher levels of interferon gamma and macrophage inflammatory protein-1β were found in participants who consumed beetroot juice.

CONCLUSION

Beetroot juice supplementation for two weeks did not to induce significant improvements in functional outcomes in adults with long COVID compared with placebo. Beneficial effects were observed in both gut microbiota composition (i.e., increase in probiotic species) and inflammatory mediators.

TRIAL REGISTRATION

Trial was registered under ClinicalTrials.gov. Identifier no. NCT06535165.

Intestinal microbiota composition in broilers fed protein-free or casein-based diets

Growing broiler chickens of the Cobb500 strain were used to determine the effects on intestinal microbiota composition of a protein-free (PF) diet as compared to a diet based in casein (CAS) as the only protein source. CAS was formulated to contain the same amount of protein (190 g kg-1) as a commercial Maize-soy diet which was used as a practical reference. The ileal AA flow (g kg-1 dry matter intake) was significantly higher (P < 0.001) than PF in birds fed protein containing diets (CAS or Maize-soy). Taken as a whole (discriminant and ANOSIM analysis), the intestinal (ileal and caecal contents and ileal tissue) microbiota composition of PF and CAS were significantly (P < 0.001) different from Maize-soy and not different from each other in some cases. RT-qPCR and sequencing analysis of the ileal and caecal microbiota revealed significant (P < 0.05) differences in a number of bacterial groups between broilers fed PF, CAS or Maize-soy diets. The main result was that the lack of protein in the intestinal medium of PF birds resulted in a drop of Lactobacillus spp. counts (on average, 43 in PF vs 1,734 in the Maize-soy diet) and increased Enterobacteriaceae (on average, 419 in PF vs 172 in the Maize-soy diet) and other potentially pathogenic bacterial groups (in both intestinal contents and tissue). Thus, the lack of protein in the intestinal medium of PF birds resulted in a microbiota composition compatible with a pro-inflammatory state, and this effect was somewhat less marked in birds fed CAS. The results reported here suggest that the adverse effects on microbiota composition in broilers fed CAS were less marked than in those fed PF, which would be in line with a preferential use of a highly digestible protein containing diet to determine endogenous AA excretion instead of a PF diet.

A polysaccharide from edible red seaweed Bangia fusco-purpurea prevents obesity in high-fat diet-induced C57BL/6 mice

The study aimed to investigate the impacts of a polysaccharide (BFP) from Bangia fusco-purpurea on high-fat diet (HFD)-induced obesity in C57BL/6 mice, as well as its underlying mechanisms. Our results showed that orally administrated BFP was more effective than inulin (INU) in reducing body weight and fat accumulation in obese mice, indicating its anti-obesity effect. BFP effectively improved the compositions and metabolites of intestinal microbiota in obese mice, leading to enhanced energy metabolism and lipid metabolism, thus contributing to its anti-obesity effect. Notably, the better anti-obesity effect of BFP compared to INU was attributed to their varying degrees of modulation of specific intestinal microbial taxa, such as Clostridium and Aerococcus, as well as the regulation of differential metabolites (including biotin, piperine, G6P, etc.) also varied. Also, both in vitro (3T3-L1 preadipocytes) and in vivo (HFD-induced obese mice) models confirmed that BFP achieved anti-obesity effect attributed to enhance energy metabolism, promote lipolysis, increase fatty acid oxidation, and inhibit adipogenesis via activating the AMP-activated protein kinase and Acetyl-CoA carboxylase signaling pathways and suppressing the peroxisome proliferator-activated receptor γ expression. Our findings suggest that BFP has the potential to be used as prebiotics, dietary agents, and nutritional supplements against obesity.

Fecal Microbiota Transplantation Activity of Floccularia luteovirens Polysaccharides and Their Protective Effect on Cyclophosphamide-Induced Immunosuppression and Intestinal Injury in Mice

Floccularia luteovirens polysaccharides (FLP1s) have potential biological activities. Our previous study showed that FLP1s positively regulated gut immunity and microbiota. However, it is still unclear whether FLP1s mediate gut microbiota in immunosuppressed mice. This research aims to explore the relationship between FLP1-mediated gut microbes and intestinal immunity in immunosuppressed mice through fecal microbiota transplantation (FMT). The results demonstrated that FLP1s exhibited prebiotic and anti-immunosuppressive effects on CTX-induced immunosuppressed mice. FFLP1 treatment (microbiota transplantation from the fecal sample) remarkably elevated the production of sIgA and secretion of the anti-inflammatory cytokines IL-4, TNF-α, and IFN-γ in the intestine of CTX-treated mice, inducing activation of the MAPK pathway. Moreover, FFLP1s mitigated oxidative stress by activating the Nrf2/Keap1 signaling pathway and strengthened the intestinal barrier function by upregulating the expression level of tight junction proteins (occludin, claudin-1, MUC-2, and ZO-1). Furthermore, FFPL1s restored gut dysbiosis in CTX-treated immunosuppressed mice by increasing the abundance of Alloprevotella, Lachnospiraceae, and Bacteroides. They also modified the composition of fecal metabolites, leading to enhanced regulation of lipolysis in adipocytes, the cGMP-PKG pathway, the Rap1 signaling pathway, and ovarian steroidogenesis, as indicated by KEGG pathway analysis. These findings indicate that FLP1s could modulate the response of the intestinal immune system through regulation of the gut microbiota, thus promoting immune activation in CTX-treated immunosuppressed mice. FLP1s can serve as a natural protective agent against CTX-induced immune injury.

The role of bound polyphenols in the anti-obesity effects of defatted rice bran insoluble dietary fiber: An insight from multi-omics

Considering the high abundance of bound polyphenols (BP) in whole grain dietary fiber (DF), this study utilized multi-omics approach to evaluate the impact of BP of defatted rice bran insoluble DF (RIDF) in modulating obesity. Mice on high-fat diet were gavage-administered RIDF, BP-removed or formulated RIDF. The results indicated that DF significantly reduced serum total cholesterol, triglycerides, high-density and low-density lipoprotein cholesterol levels. Moreover, hepatic lipid accumulation and damage induced by high-fat diet were significantly ameliorated with DF intervention. The presence of BP increased the abundance of beneficial bacteria g_Akkermansia and g_Butyricicocus, as well as the expression of butyric acid/propionic acid. Furthermore, the expression of hepatic lipids and lipid-like molecules was significantly decreased under the combined intervention of BP and DF, and this was accompanied by alterations in genes related to lipid, sterol, and cholesterol metabolic biological processes. These findings suggest that BP contribute to the anti-obesity effects of DF.

Gut microbiota profiling in injection drug users with and without HIV-1 infection in Puerto Rico

Introduction

The full extent of interactions between human immunodeficiency virus (HIV) infection, injection drug use, and the human microbiome is unclear. In this study, we examined the microbiomes of HIV-positive and HIV-negative individuals, both drug-injecting and non-injecting, to identify bacterial community changes in response to HIV and drug use. We utilized a well-established cohort of people who inject drugs in Puerto Rico, a region with historically high levels of injection drug use and an HIV incidence rate disproportionately associated with drug use.

Methods

Using amplicon-based 16S rDNA sequencing, we identified amplicon sequence variants (ASVs) that demonstrated significant variations in the composition of microbial communities based on HIV status and drug use.

Results and discussion

Our findings indicate that the HIV-positive group exhibited a higher abundance of ASVs belonging to the genera Prevotella, Alloprevotella, Sutterella, Megasphaera, Fusobacterium, and Mitsuokella. However, Bifidobacteria and Lactobacillus ASVs were more abundant in injectors than in non-injectors. We examined the effect of drug use on the gut microbiome in both HIV-infected and non-infected patients, and found that multiple drug use significantly affected the microbial community composition. Analysis of differential of bacterial taxa revealed an enrichment of Bifidobacterium spp., Faecalibacterium spp., and Lactobacillus spp. in the multiple drug-injecting group. However, in the non-injecting group, Parabacteroides spp., Prevotella spp., Paraprevotella spp., Sutterella spp., and Lachnoclostridium spp. The presence of multiple drug-injecting groups was observed to be more prevalent. Our findings provide detailed insight into ASV-level changes in the microbiome in response to HIV and drug use, suggesting that the effect of HIV status and drug injection may have different effects on microbiome composition and in modulating gut bacterial populations.

Lactiplantibacillus plantarum Y44 Complex Fermented Milk Regulates Lipid Metabolism in Mice Fed with High-Fat Diet by Modulating Gut Microbiota

The benefits of fermented milk containing Lactiplantibacillus plantarum (L. plantarum) Y44, known for its weight loss properties, remain unclear. For this, we evaluated the effects of the complex fermented milk (Y44-CFM), obtained through the cofermentation of cow's milk and soybean milk with L. plantarum Y44 and traditional starters, on high-fat diet (HFD)-fed C57BL/6 mice. Our study found that the oral administration of Y44-CFM significantly reduced body weight gain and hepatic lipid accumulation in HFD-fed mice while also mitigating liver injury. Additionally, Y44-CFM regulated the expression of enzymes associated with lipid metabolism in the serum, as well as the corresponding or related genes in the liver, such as fatty acid synthase. Furthermore, HFD-induced systemic inflammation, oxidative stress, and intestinal barrier dysfunction were improved. The primary alterations in hepatic metabolism involved glycerophospholipids and amino acids, including the biosynthesis of valine, leucine, and isoleucine. The diversity and overall structure of the gut microbiota were also regulated, resulting in a significant decrease in the ratio of Firmicutes to Bacteroidetes (F/B) and unclassified_f_Lachnospiraceae, along with a notable increase in Oscillospiraceae. The correlation analysis indicated that Y44-CFM influenced hepatic lipid metabolism by mediating intestinal flora and its production of short-chain fatty acids, ultimately leading to weight reduction.

Effect of Postbiotic Bifidobacterium longum CECT 7347 on Gastrointestinal Symptoms, Serum Biochemistry, and Intestinal Microbiota in Healthy Adults: A Randomised, Parallel, Double-Blind, Placebo-Controlled Pilot Study

OBJECTIVES

A randomised, double-blind, placebo-controlled pilot trial was conducted to assess the effect of heat-treated Bifidobacterium longum CECT 7347 (HT-ES1) in healthy adults with mild to moderate digestive symptoms. A total of 60 participants were recruited and received either HT-ES1 or an identical placebo for 8 weeks with a further follow-up at week 10.

METHODS

This study monitored changes in the total Gastrointestinal Symptom Rating Scale for IBS score (GSRS-IBS), Irritable Bowel Syndrome Symptom Severity Scale (IBS-SSS), IBS Quality of Life index (IBS-QoL), gut microbiome using 16S rRNA sequencing, and the Visceral Sensitivity Index, as well as a range of biochemical markers, anthropometric parameters, and adverse events.

RESULTS

While minimal changes were observed in gastrointestinal (GI) symptoms, the HT-ES1 group showed a significant decrease in total and non-HDL cholesterol compared to the placebo. The intervention group also exhibited a significant increase in the abundance of the genera Faecalibacterium and Anaerobutyricum, both of which were positively correlated with butyrate concentrations. Faecal calprotectin significantly increased over time in the placebo group but remained stable in the HT-ES1 group.

CONCLUSIONS

Overall, these findings suggest that HT-ES1 may promote gut health by increasing butyrate-producing bacteria in the gut, maintaining normal levels of faecal calprotectin and reducing serum cholesterol.

Gastrointestinal complaints after Roux-en-Y gastric bypass surgery. Impact of microbiota and its metabolites

Unexplainable gastrointestinal complaints occasionally occur after Roux-en-Y Gastric Bypass (RYGB) surgery. We therefor investigated the impact of microbiota composition and metabolites on gastrointestinal complaints after RYGB. In the BARICO study (Bariatric surgery Rijnstate and Radboudumc neuroimaging and Cognition in Obesity), microbiota and metabolites were measured before surgery, and 6, and 24 months after surgery. Gastrointestinal complaints were assessed with the Irritable Bowel Syndrome Severity Scoring System (IBS-SSS) questionnaire 24 months after surgery. 65 participants (86.2 % female) with a mean age of 46.2 ± 6.0 years, and mean BMI of 41.2 ± 3.6 kg/m2 were included. According to the IBS-SSS questionnaire, 32.3 % had moderate/severe gastrointestinal complaints 24 months after surgery. Microbiota alpha diversity remained stable, while beta diversity significantly changed over time. Bile acids and short-chain fatty acids were significantly higher, and inflammatory markers significantly lower after surgery. Barnesiella sp., Escherichia/Shigella sp., and Faecalibacterium prausnitzii correlated positively, while Akkermansia sp correlated inversely with gastrointestinal complaints. Patients with mild and moderate/severe gastrointestinal complaints showed higher levels of GLC-3S. These findings suggest involvement of microbiota and metabolite changes in gastrointestinal complaints after surgery. However, it remains unclear whether bacteria influence gastrointestinal complaints directly or indirectly. Further exploration is required for development of interventions against gastrointestinal symptoms after surgery.

The sports performance improving effects of konjac glucomannan with varying molecular weights in overtrained mice

Overtraining affects individuals engaged in high-volume training, potentially hindering athletic performance and revealing shortcomings in suggested solutions. This study evaluated the impact of konjac glucomannan (KGM) with varying molecular weights on the gut microbiome, endurance, and strength in mice subjected to excessive training. The native KGM (1.82 × 107 Da) was enzymatically degraded using endo-1,4-β-mannanase to generate moderate molecular weight KGM (KGM-EM, 1.89 × 105 Da) and low molecular weight KGM (KGM-EL, 1.34 × 104 Da). These fractions were characterized and compared with the native KGM regarding their effects on mice undergoing excessive training. The results demonstrated a positive correlation between KGM's molecular weight and its capacity to mitigate the adverse impacts of excessive training on strength or/and endurance (a significant increase of 55.57 % and 55.70 % by the native KGM compared with the excessive training group). In addition, the native KGM exhibited superior preservation of microbial diversity and composition in fecal samples against excessive training-induced shifts, along with increased production of individual and total short-chain fatty acids in plasma compared with the two degraded products. Overall, these results highlight the potential benefits of high molecular weight KGM for preventing overtraining syndrome and enhancing athletic performance in animal models.

Impact of high-fructose diet and metformin on histomorphological and molecular parameters of reproductive organs and vaginal microbiota of female rat

There are limited data on the effects of a high-fructose diet on the female reproductive system. Although metformin has some functional effects on female fertility, its reproductive outcome on high fructose diet-induced metabolic syndrome is unclear. The aim of the present study is to evaluate the impact of a high fructose diet on histomorphological and molecular parameters of the reproductive organs and vaginal microbiota as well as the treatment potential of metformin. Wistar albino rats were used in the study. The metabolic syndrome model was induced by a high-fructose diet in rats for 15 weeks. Metformin was orally administered once a day for the last 6 weeks. The high-fructose diet increased blood glucose, triglycerides, insulin, and ovarian testosterone levels; however, it reduced ovarian aromatase levels and follicle numbers and caused uterine inflammation. The high-fructose diet-induced molecular abnormalities on ovarian tissue were demonstrated by the downregulation of ovarian insulin signaling pathway proteins and dysregulation of ovarian mitogenic and apoptotic pathway proteins. A high-fructose diet caused vaginal dysbiosis, metformin increased probiotic bacteria in the vaginal microbiota. Our results revealed that metformin improves ovarian impairments by modulating hormonal balance, insulin level, mapk, and apoptotic signaling molecules, as well as regulating the vaginal microbiota.

Uncovering new Firmicutes species in vertebrate hosts through metagenome-assembled genomes with potential for sporulation

Metagenome-assembled genomes (MAGs) have contributed to identifying non-culturable microorganisms and understanding their ecological functions. MAGs offer an advantage in investigating sporulation-associated genes, especially given the difficulty of isolating many species residing in the gut microbiota of multiple hosts. Bacterial sporulation is a key survival mechanism with implications for pathogenicity and biotechnology. Here, we investigate MAGs from vertebrate hosts, emphasizing taxonomic identification and identifying sporulation-associated genes in potential novel species within the Firmicutes phylum. We identified potential new species in the classes Clostridia (Borkfalkiaceae, Lachnospiraceae, Monoglobaceae, and Oscillospiraceae families) and Bacilli (Bacillaceae and Erysipelotrichaceae families) through phylogenetic and functional pathway analyses, highlighting their sporulation potential. Our study covers 146 MAGs, 124 of them without refined taxonomic assignments at the family level. We found that Clostridia and Bacilli have unique sporulation gene profiles in the refined family MAGs for cattle, swine, poultry, and human hosts. The presence of genes related to Spo0A regulon, engulfment, and spore cortex in MAGs underscores fundamental mechanisms in sporulation processes in currently uncharacterized species with sporulation potential from metagenomic dark matter. Furthermore, genomic analyses predict sporulation potential based on gene presence, genome size, and metabolic pathways involved in spore formation. We emphasize MAGs covering families not yet characterized through the phylogenetic analysis, and with extensive potential for spore-forming bacteria within Clostridia, Bacilli, UBA4882, and UBA994 classes. These findings contribute to exploring spore-forming bacteria, which provides evidence for novel species diversity in multiple hosts, their adaptive strategies, and potential applications in biotechnology and host health.IMPORTANCESpores are essential for bacterial survival in harsh environments, facilitating their persistence and adaptation. Exploring sporulation-associated genes in metagenome-assembled genomes (MAGs) from different hosts contributes to clinical and biotechnological domains. Our study investigated the extent of genes associated with bacterial sporulation in MAGs from poultry, swine, cattle, and humans, revealing these genes in uncultivated bacteria. We identified potential novel Firmicutes species with sporulation capabilities through phylogenetic and functional analyses. Notably, MAGs belonging to Clostridia, Bacilli, and unknown classes, namely UBA4882 and UBA994, remained uncharacterized at the family level, which raises the hypothesis that sporulation would also be present in these genomes. These findings contribute to our understanding of microbial adaptation and have implications for microbial ecology, underlining the importance of sporulation in Firmicutes across different hosts. Further studies into novel species and their sporulation capability can contribute to bacterial maintenance mechanisms in various organisms and their applications in biotechnology studies.

Causal relationship between bladder cancer and gut microbiota contributes to the gut-bladder axis: A two-sample Mendelian randomization study

BACKGROUND

Recent studies have underscored a potential link between gut microbiota and urological tumors, yet the causal relationship with bladder cancer (BCa) and the role of metabolic pathways remain unclear.

METHODS

Instrumental variables (IVs) for gut microbiota were obtained from genome-wide association studies (GWAS) conducted by the MiBioGen consortium (n = 18,340). GWAS data for BCa were sourced from a comprehensive genome-wide meta-analysis encompassing 23 cohorts. Mendelian randomization (MR) was employed to investigate the causal relationship between gut microbiota and BCa, utilizing inverse variance weighted (IVW) as the primary MR method. Additionally, metabolic pathways associated with these microbiota were analyzed to understand their functional roles in BCa pathogenesis. Sensitivity analyses were conducted to validate all MR results.

RESULTS

The MR analysis identified five gut microbiota taxa with a causal association with BCa, with the genus Bilophila notably promoting BCa. Metabolic pathway analysis revealed significant associations between specific pathways and BCa, suggesting that changes in amino acid and NAD metabolism might influence BCa development. Sensitivity analyses indicated no significant heterogeneity or horizontal pleiotropy among the IVs.

CONCLUSION

This study revealed the significant causal relationship between gut microbiota and BCa, particularly identifying Bilophila as a key pathogenic initiator. These findings elucidated the potential impact of metabolic pathways, especially amino acid and NAD metabolism, on the pathogenesis of BCa. They not only laid the foundation for innovative therapeutic strategies but also highlighted the immense potential of microbiota-based interventions in the prevention and treatment of BCa, paving the way for new directions in precision medicine.

Dietary Dihydromyricetin Zinc Chelate Supplementation Improves the Intestinal Health of Magang Geese

To fulfill the nutritional requirements of poultry, effective Zn supplementation is required due to Zn deficiency in basic feed. In this study, we investigated the effects of DMY-Zn (dihydromyricetin zinc chelate) on the growth performance, morphology, and biochemical indices; the expression of intestinal barrier-related genes; the intestinal microflora; and the cecum metabolome of Magang geese. A total of 300 14-day-old Magang geese (equal number of males and females) with an average body weight of 0.82 ± 0.08 kg were randomly divided into five groups and fed a basal diet; these groups were given DMY-Zn (low, medium, or high level of DMY-Zn with 30, 55, or 80 mg/kg Zn added to the basal diet) or ZnSO4 (80 mg/kg Zn added) for 4 weeks. Our results revealed that DMY-Zn significantly impacts growth and biochemical indices and plays a significant role in regulating the intestinal barrier and microflora. DMY-Zn is involved in the upregulation of intestinal barrier gene (ZO1 and MUC2) expression, as well as upregulated Zn-related gene expression (ZIP5). On the other hand, a low concentration of DMY-Zn increased the ɑ diversity index and the abundance of Lactobacillus and Faecalibacterium. Additionally, a cecal metabolomics study showed that the main metabolic pathways affected by DMY-Zn were the pentose phosphate pathway, the biosynthesis of different alkaloids, and the metabolism of sphingolipids. In conclusion, DMY-Zn can reduce feed intake, increase the expression of intestinal barrier-related genes, help maintain the intestinal microflora balance, and increase the abundance of beneficial bacteria in the intestine to improve intestinal immunity.

Polysaccharides in Medicinal and Food Homologous Plants regulate intestinal flora to improve type 2 diabetes: Systematic review

BACKGROUND

Medicinal and food homologous plants (MFHPs) which can improve Type 2 Diabetes Mellitus (T2DM) draw significant attention among the public due to their low toxicity and more safety. Polysaccharides, one of the various active components of MFHPs, are recognized as effective modulators of the intestinal flora. By altering the composition of intestinal flora and affecting their metabolic products, polysaccharides can improve T2DM, making them a central focus of anti-diabetic research.

PURPOSE

The purpose of this study is to systematically review the mechanism by which polysaccharides from MFHPs (MFHPPs) regulate the composition of intestinal flora and its metabolic products to improve T2DM.

METHODS

This study follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and conducts a comprehensive search on the PubMed, Web of Science and Embase databases. All experimental articles published up to March 4, 2024, are included in the search.

RESULTS

Among the 5733 articles reviewed, 29 were selected, covering 22 different MFHPs. MFHPPs can improve T2DM, particularly in lowering blood glucose levels, with consistent results. MFHPPs can regulate the diversity of intestinal flora in T2DM animal models, primarily affecting four phyla: decreasing Firmicutes and Proteobacteria while increasing Bacteroidetes and Actinobacteriota. At the genus level, the improvement of T2DM by MFHPPs is associated with the modulation of 12 key genera: Allobaculum, Akkermansia, Bifidobacterium, Lactobacillus, Helicobacter, Halomonas, Olsenella, Oscillospira, Shigella, Escherichia-Shigella, Romboutsia and Bacteroides. At the molecular level, MFHPPs primarily act by modulating the intestinal flora to increase short-chain fatty acid levels, promote the secretion of glucagon-like peptide-1, influence the IGF1/PI3K/AKT signaling pathway, or the PI3K/AKT/GSK-3β pathway, to lower blood glucose levels. They may also improve T2DM by working in glucose metabolism through the "microbiota-gut-organ" axis. MFHPPs can also alleviate T2DM by mitigating inflammation and oxidative stress: MFHPPs regulate intestinal flora to reduce lipopolysaccharide "leakage" and enhance intestinal mucosal permeability to tackle the inflammation associated with T2DM; MFHPPs enhance the expression of oxidative stress-related enzymes to alleviate oxidative stress and improve T2DM. Lastly, from a metabolic pathway perspective, MFHPPs are primarily involved in the metabolism of amino acids and their derivatives, carbohydrate metabolism and glutathione metabolism.

CONCLUSION

MFHPPs can improve T2DM by enhancing the composition of intestinal flora, regulating its metabolic products to promote insulin secretion, inhibiting glucagon-like peptide secretion, facilitating glycogen synthesis, reducing inflammation levels and alleviating oxidative stress. Furthermore, MFHPPs demonstrate potential protective effects on critical organs such as the pancreas, liver, kidneys and heart. Therefore, MFHPPs demonstrate significant clinical potential. However, most studies can only indicate the potential of MFHPPs intervention in improving T2DM through the intestinal flora. The causality between MFHPPs regulating the intestinal flora and T2DM requires further investigation.

Gut Microbiota Composition Positively Correlates with Sports Performance in Competitive Non-Professional Female and Male Runners

There is still a pressing need for further investigation to bridge the gap in understanding the differences in gut microbiota composition between female runners and their male counterparts. We aimed to determine the gut microbiota composition in competitive non-professional female and male runners and to correlate the gut bacteria to performance. Our study included 40 subjects, of which 22 were runners (13 males and 9 females) and 18 control subjects (9 males and 9 females, representing the general population who perform light physical activity with a weekly running volume of ≤5 km per week). Fecal specimens were collected and analyzed for taxonomic profiling to compare species' relative abundances between males and females based on the results of 16SrRNA analysis. Bacterial alpha and beta diversity were assessed to determine the differences in microbial composition between runners and controls, and between sexes. Each participant underwent a maximal oxygen consumption test and a time-to-exhaustion test at 85% of the measured VO2max. Blood lactate was collected every 5 min during the tests. Bacterial alpha diversity showed a significant difference (p = 0.04) between runners and controls. Taxonomic analysis of gut microbiota composition showed a lower Enterobacteriaceae abundance and a higher Methanosphaera abundance in runners compared with the control group. Ten different bacteria (Methanosphaera, Mitsuokella, Prevotellaceae, Megamonas, Rothia, Oscillospira, Bacteroides, Odoribacter, Blautia massiliensis, Butyricicoccus_pullicaecorum) were positively correlated with exercise (VO2max, lactate blood levels, time to exhaustion, and weekly training volume). We found no significant differences in the gut microbiota composition between male and female runners. Gut microbiota composition positively correlates with sports performance in competitive non-professional female and male runners, and female runners show similar gut microbiome diversity to male runners.

Microbiome-induced increases and decreases in bone matrix strength can be initiated after skeletal maturity

Recent studies in mice have indicated that the gut microbiome can regulate bone tissue strength. However, prior work involved modifications to the gut microbiome in growing animals and it is unclear if the same changes in the microbiome, applied later in life, would change matrix strength. Here we changed the composition of the gut microbiome before and/or after skeletal maturity (16 weeks of age) using oral antibiotics (ampicillin + neomycin). Male and female mice (n = 143 total, n = 12-17/group/sex) were allocated into five study groups: (1) Unaltered, (2) Continuous (dosing 4-24 weeks of age), (3) Delayed (dosing only 16-24 weeks of age), (4) Initial (dosing 4-16 weeks of age, suspended at 16 weeks), and (5) Reconstituted (dosing from 4-16 weeks following by fecal microbiota transplant from Unaltered donors). Animals were euthanized at 24 weeks of age. In males, bone matrix strength in the femur was 25%-35% less than expected by geometry in mice from the Continuous (p = 0.001), Delayed (p = 0.005), and Initial (p = 0.040) groups as compared to Unaltered. Reconstitution of the gut microbiota led to a bone matrix strength similar to Unaltered animals (p = 0.929). In females, microbiome-induced changes in bone matrix strength followed the same trend as males but were not significantly different, demonstrating a sex-dependent response of bone matrix to the gut microbiota. Minor differences in chemical composition of bone matrix were observed with Raman spectroscopy. Our findings indicate that microbiome-induced impairment of bone matrix in males can be initiated and/or reversed after skeletal maturity. The portion of the femoral cortical bone formed after skeletal maturity (16 weeks) was small; suggesting that microbiome-induced changes in bone matrix occurred without osteoblast/osteoclast turnover through a yet unidentified mechanism. These findings provide evidence that the mechanical properties of bone matrix can be altered in the adult skeleton.

Danshen polysaccharides alleviate AFB1 induced Jejunal injury

AFB1 is a common foodborne toxin known for its potent carcinogenicity. Danshen polysaccharide (DSP) is an active ingredient of Danshen, which has been demonstrated to possess support intestinal homeostasis and anti-inflammatory activities. We utilized New Zealand White rabbits as an animal model to examine the impact of co-exposure to DSP and AFB1 on the intestines, as well as their underlying mechanisms. The results indicate that DSP elevated the abundance of Oscillospira, Coprococcus, Alistipes, Akkermansia, Bacteroides, Odoribacter, Blautia and Parabacteroides, while decreased the abundance of Sutterella, and Desulfovibrio, correcting AFB1-induced intestinal microbiota dysbiosis and enhancing microbial diversity within the gut. Moreover, DSP reduced the levels of diamine oxidase (DAO), D-Lactate, and malondialdehyde (MDA), while upregulating the expression of total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px), zonula occludens-1 (ZO-1), occludin, claudin-4, mucin-2 (MUC2), and secretory immunoglobulin A (sIgA), thereby alleviating the oxidative stress and intestinal barrier dysfunction induced by AFB1. DSP downregulated jejunal lipopolysaccharide (LPS) levels and the mRNA expression and proteins abundance of toll-like receptor 4 (TLR4), myeloiddifferentiationfactor 88 (MyD88), and nuclear factor kappa-B (NF-κB), thereby inhibiting the jejunal inflammation induced by AFB1. In summary, DSP alleviates AFB1-induced jejunal injury by remodeling the gut microbiota, bolstering antioxidant capabilities within the jejunum, fortifying the intestinal barrier, and suppressing the TLR4-mediated release of pro-inflammatory cytokines.

Responses of Intestinal Antioxidant Capacity, Morphology, Barrier Function, Immunity, and Microbial Diversity to Chlorogenic Acid in Late-Peak Laying Hens

This study examined the influence of chlorogenic acid (CGA) on gut antioxidant status, morphology, barrier function, immunity, and cecal microbiota in late-peak laying hens. A total of 240 Hy-Line Brown hens, aged 43 weeks, were randomly assigned to four groups, the basal diet +0, 400, 600, and 800 mg/kg CGA, for 12 weeks. The results revealed that CGA significantly reduced ileal H2O2 and malondialdehyde levels; increased duodenal height, ileal villus height, and villus height-to-crypt depth ratio; while decreasing jejunal crypt depth. The 600 and 800 mg/kg CGA significantly upregulated the duodenal, jejunal, and ileal ZO-1 and occludin gene expression; increased IgG levels in serum and ileum; and upregulated ileal IgA gene expression. The 600 mg/kg CGA significantly upregulated CD3D and CD4 gene expression, while downregulating IL-1β gene expression in duodenum, jejunum, and ileum. Moreover, CGA changed the gut microbiota structure. The SCFA-producing bacteria unclassified_f__Peptostreptococcaceae, unclassified_f_Oscillospiraceae, Pseudoflavonifractor, Lachnospiraceae_FCS020_group, Oscillospira, Elusimicrobium, Eubacterium_ventriosum_group, Intestinimonas, and norank_f_Coriobacteriales_Incertae_Sedis were significantly enriched in the 400, 600, and/or 800 mg/kg CGA groups. The bacteria Lactobacillus, Bacillus, and Akkermansia were significantly enriched in the 600 mg/kg CGA group. Conclusively, dietary CGA (600-800 mg/kg) improved intestinal antioxidant status, morphology, barrier and immune function, and beneficial microbiota growth in late-peak laying hens.

Effect of host breeds on gut microbiome and fecal metabolome in commercial pigs

BACKGROUND

Gut microbial composition and its metabolites are crucial for livestock production performance. Metabolite profiles from autopsied biospecimens provide vital information on the basic mechanisms that affect the overall health and production traits in livestock animals. However, the role of the host breed in the gut microbiome and fecal metabolome of commercial pigs remains unclear. In this work, differences in microbiota composition among three commercial pig breeds Duroc, Yorkshire, and Landrace were measured by 16S rRNA gene sequencing. Fecal metabolite compositions of the three pig breeds were detected using untargeted metabolomics.

RESULTS

There were significant differences in the gut microbiomes of the three species, indicating that host breed affects the diversity and structure of gut microbiota. Several breed-associated microorganisms were identified at different taxonomic levels. Notely, most microbial taxa were annotated as Lactobacillacea, Muribaculaceae, and Oscillospiraceae. Several bacteria, including Lactobacillus, Subdoligranulum, Faecalibacterium, Oscillospira, Oscillospiraceae_UCG-002, and Christensenellaceae_R-7_group, could be considered as biomarkers for improving the backfat thickness (BF) for commercial pigs. Additionally, KEGG analysis of gut microbiota further revealed that arginine biosynthesis, pyruvate metabolism, and fatty acid biosynthesis varied greatly among pig breeds. Multiple gut bacterial metabolites (e.g., spermidine, estradiol, and palmitic acid) were identified as breed-associated. Mediation analysis ultimately revealed the cross-talk among gut microbiota, metabolites, and BF thickness, proclaiming that the microbial and metabolic biomarkers identified in this study could be used as biomarkers for improving BF phenotype.

CONCLUSIONS

This work provides vital insights into breed effects on gut microbiota and metabolite compositions of commercial pigs and uncovers potential biomarkers that are significant for pig breed improvement.

Chronological dynamics of the gut microbiome in response to the pasture grazing system in geese

It is commonly accepted that dietary fibers are good for gut health. The effect of fibers on the diversity and metabolic activities of the cecal microflora, however, differ with the passage of time. Therefore, we investigated the time-series impacts of the pasture grazing system (a high dietary fiber source) on the cecal microbiome and short-chain fatty acids in Wanpu geese, comparing it to commercial feeding (a low dietary fiber source). The cecal microbiota composition and SCFA concentrations were evaluated by 16S rRNA gene sequencing and gas chromatography, respectively. We found that pasture produced a generally quick positive response to Bacteroidales, Lactobacillales, Gastranaerophilales (at 45 days), Lachnospirales, and Oscillospirales (at 60 days and 90 days) irrespective of Erysipelotrichales (at 45 days), Clostridia_UCG-014, RF39 (at 60 days), Christensenellales, and Peptostreptococcales-Tissierellales (at 90 days) in geese. Meanwhile, we found that Lactobacillales, Gastranaerophilales, Lachnospirales, and Oscillospirales were significantly correlated with short-chain fatty acids in pasture grazing geese. Indeed, the correlation of cecal microbiota with SCFAs led to altered microbial functions evinced by COG; KEGG pathway levels 1, 2, and 3; BugBase; and FAPROTAX databases. This study emphasizes the importance of dietary fiber sources in influencing beneficial impacts in regulating geese microbiota homeostasis and metabolic functions such as energy and lipid metabolism.IMPORTANCELow dietary fiber diet sources cause gut microbial and short-chain fatty acid alterations that lead to compromised animal health. The establishment of an artificial pasture grazing system at the expense of ryegrass is a good source of dietary fiber for geese. Our results described the importance of pasture in maintaining the gut microbiota, SCFAs, and potential microbial functions reported by COG; KEGG pathway levels 1, 2, and 3; BugBase; and FAPROTAX databases.

Microbiome time series data reveal predictable patterns of change

The human gut microbiome is crucial in health and disease. Longitudinal studies are becoming increasingly important compared to traditional cross-sectional approaches, as precision medicine and individualized interventions are coming to the forefront. Investigating the temporal dynamics of the microbiome is essential for comprehending its function and impact on health. This knowledge has implications for targeted therapeutic strategies, such as personalized diets or probiotic therapy. In this study, we focused on developing and implementing methods specifically designed for analyzing gut microbiome time series. Our statistical framework provides researchers with tools to examine the temporal behavior of the gut microbiome. Key features of our framework include statistical tests for time series properties, predictive modeling, classification of bacterial species based on stability and noise, and clustering analyses to identify groups of bacteria with similar temporal patterns. We analyzed dense amplicon sequencing time series from four generally healthy subjects. Using our developed statistical framework, we analyzed both the overall community dynamics and the behavior of individual bacterial species. We showed six longitudinal regimes within the gut microbiome and discussed their features. Additionally, we explored whether specific bacterial clusters undergo similar fluctuations, suggesting potential functional relationships and interactions within the microbiome. Our development of specialized methods for analyzing human gut microbiome time series significantly enhances the understanding of its dynamic nature and implications for human health. The guidelines and tools provided by our framework support scientists in studying the complex dynamics of the gut microbiome, fostering further research and advancements in microbiome analysis. The gut microbiome is integral to human health, influencing various diseases. Longitudinal studies offer deeper insights into its temporal dynamics compared to cross-sectional approaches. In this study, we developed a statistical framework for analyzing the time series of the human gut microbiome. This framework provides robust tools for examining microbial community dynamics over time. It includes statistical tests for time series properties, predictive modeling, classification of bacterial species based on stability and noise, and clustering analyses. Our approach significantly enhances the methodologies available to researchers, promoting further exploration and innovation in microbiome analysis.

IMPORTANCE

This project developed innovative methods to analyze gut microbiome time series data, offering fresh insights into its dynamic nature. Unlike many studies that focus on static snapshots, we found that the healthy gut microbiome is predictably stable over time, with only a small subset of bacteria showing significant changes. By identifying groups of bacteria with diverse temporal behaviors and clusters that change together, we pave the way for more effective probiotic therapies and dietary interventions, addressing the overlooked dynamic aspects of gut microbiome changes.

Study on the physicochemical properties and gut microbiota regulation of Poria cocos pachyman treated by ball milling

The effect of ball milling on the physicochemical properties and gut microbiota regulation of Poria cocos pachyman (PAC) was investigated. Ball milling reduced the particle size of PAC from 102 μm to 25.19 μm after 12 h, resulting in increasing particle uniformity. Scanning electron microscopy (SEM) revealed surface roughening and fragmentation of PAC after ball milling. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) indicated reduced crystallinity and increased hydroxyl group exposure in ball-milled PAC (BMP). Thermogravimetric analysis (TGA) showed decreased thermal stability in BMP. The optimal ball milled time was 7 h. Moisture contents in PAC and BMP-7 h were 10.30 ± 0.47 % and 10.72 ± 0.12 %, and carbohydrate contents were 81.02 ± 2.27 % and 74.54 ± 1.46 %. In vivo studies on mice demonstrated that both PAC and BMP-7 h increased diversity and reshaped the composition of gut microbiota, with BMP-7 h showing a more pronounced effect. BMP-7 h reduced the Firmicutes/Bacteroidetes ratio, and raised the abundance of Bacteroides, suggesting enhanced prebiotic potential. These findings highlight the role of ball milling in improving the physicochemical properties and prebiotic potential of water-insoluble polysaccharides and provide a theoretical basis for its broader application in the food and biopharmaceutical industries.

Exploring the anti-inflammatory effects of postbiotic proteins from Lactobacillus delbrueckii CIDCA 133 on inflammatory bowel disease model

Lactobacillus delbrueckii CIDCA 133 is a promising health-promoting bacterium shown to alleviate intestinal inflammation. However, the specific bacterial components responsible for these effects remain largely unknown. Here, we demonstrated that consuming extractable proteins from the CIDCA 133 strain effectively relieved acute ulcerative colitis in mice. This postbiotic protein fraction reduced the disease activity index and prevented colon shortening in mice. Furthermore, histological analysis revealed colitis prevention with reduced inflammatory cell infiltration into the colon mucosa. Postbiotic consumption also induced an immunomodulatory profile in colitic mice, as evidenced by both mRNA transcript levels (Tlr2, Nfkb1, Nlpr3, Tnf, and Il6) and cytokines concentration (IL1β, TGFβ, and IL10). Additionally, it enhanced the levels of secretory IgA, upregulated the transcript levels of tight junction proteins (Hp and F11r), and improved paracellular intestinal permeability. More interestingly, the consumption of postbiotic proteins modulated the gut microbiota (Bacteroides, Arkkemansia, Dorea, and Oscillospira). Pearson correlation analysis indicated that IL10 and IL1β levels were positively associated with Bacteroides and Arkkemansia_Lactobacillus abundance. Our study reveals that CIDCA 133-derived proteins possess anti-inflammatory properties in colonic inflammation.

High value-added chemical production through anaerobic codigestion of corn straw with a microbial consortium, cow manure and cow digestion solution

OBJECTIVES

This study investigated the codigestion of corn straw (CS) with cow manure (CM), cow digestion solution (CD), and a strain consortium (SC) for enhanced volatile fatty acid (VFA) production. The aims of this study were to develop a sustainable technique to increase VFA yields, examine how combining microbial reagents with CS affects VFA production by functional microorganisms, and assess the feasibility of improving microbial diversity through codigestion.

METHODS

Batch experiments evaluated VFA production dynamics and microbial community changes with different combinations of CS substrates with CM, CD, and SC. Analytical methods included measuring VFAs by GC, ammonia and chemical oxygen demand (COD) by standard methods and microbial community analysis by 16S rRNA gene sequencing.

RESULTS

Codigesting CS with the strain consortium yielded initial VFA concentrations ranging from 0.6 to 1.0 g/L, which were greater than those of the other combinations (0.05-0.3 g/L). Including CM, and CD further increased VFA production to 1.0-2.0 g/L, with the highest value of 2.0 g/L occurring when all four substrates were codigested. Significant ammonium reduction (194-241 mg/L to 29-37 mg/L) and COD reduction (3310-5250 mg/L to 730-1210 mg/L) were observed. Codigestion with CM and CD had greater Shannon diversity indices (3.19-3.24) than did codigestion with the other consortia (2.26). Bacillota dominated (96.5-99.6 %), with Clostridiales playing key roles in organic matter breakdown.

CONCLUSIONS

This study demonstrated the feasibility of improving VFA yields and harnessing microbial diversity through anaerobic codigestion of lignocellulosic and animal waste streams. Codigestion substantially enhanced VFA production, which was dominated by butyrate, reduced ammonium and COD, and enriched fiber-degrading and fermentative bacteria. These findings can help optimize codigestion for sustainable waste management and high-value chemical production.

Potential Applications of Blautia wexlerae in the Regulation of Host Metabolism

Blautia wexlerae (B. wexlerae) is a strong candidate with the potential to become a next-generation probiotics (NGPs) and has recently been shown for the first time to exhibit potential in modulating host metabolic levels and alleviating metabolic diseases. However, the factors affecting the change in abundance of B. wexlerae and the pattern of its abundance change in the associated indications remain to be further investigated. Here, we summarize information from published studies related to B. wexlerae; analyze the effects of food source factors such as prebiotics, probiotics, low protein foods, polyphenols, vitamins, and other factors on the abundance of B. wexlerae; and explore the patterns of changes in the abundance of B. wexlerae in metabolic diseases, neurological diseases, and other diseases. At the same time, the development potential of B. wexlerae was evaluated in the direction of functional foods and special medical foods.

Analysis of the liver-gut axis including metabolomics and intestinal flora to determine the protective effects of kiwifruit seed oil on CCl4-induced acute liver injury

The hepatoprotective effects of kiwifruit seed oil (KSO) were evaluated on acute liver injury (ALI) induced by carbon tetrachloride (CCl4) in vivo. Network pharmacology was used to predict active compounds and targets. Metabolomics and gut microbiota analyses were used to discover the activity mechanism of KSO. KSO improved the liver histological structure, significantly reduced serum proinflammatory cytokine levels, and increased liver antioxidant capacity. The metabolomics analysis showed that KSO may have hepatoprotective effects by controlling metabolites through its participation in signaling pathways like tryptophan metabolism, glycolysis/gluconeogenesis, galactose metabolism, and bile secretion. The gut microbiota analysis demonstrated that KSO improved the composition and quantity of the gut flora. Network pharmacological investigations demonstrated that KSO operated by altering Ptgs2, Nos2, Ppara, Pparg and Serpine1 mRNA levels. All evidence shows that KSO has a hepatoprotective effect, and the mechanism is connected to the regulation of metabolic disorders and intestinal flora.

Effects of Kimchi Intake on the Gut Microbiota and Metabolite Profiles of High-Fat-Induced Obese Rats

With rising global obesity rates, the demand for effective dietary strategies for obesity management has intensified. This study evaluated the potential of kimchi with various probiotics and bioactive compounds as a dietary intervention for high-fat diet (HFD)-induced obesity in rats. Through a comprehensive analysis incorporating global and targeted metabolomics, gut microbiota profiling, and biochemical markers, we investigated the effects of the 12-week kimchi intake on HFD-induced obesity. Kimchi intake modestly mitigated HFD-induced weight gain and remarkably altered gut microbiota composition, steroid hormones, bile acids, and metabolic profiles, but did not reduce adipose tissue accumulation. It also caused significant shifts in metabolomic pathways, including steroid hormone metabolism, and we found substantial interactions between dietary interventions and gut microbiota composition. Although more research is required to fully understand the anti-obesity effects of kimchi, our findings support the beneficial role of kimchi in managing obesity and related metabolic disorders.

Allergenic risk assessment of porcine myoglobin expressed by engineered Komagataella Phaffii

Myoglobin produced by fermentation using engineered Komagataella phaffii is an important color additive in meat analogue products, but its allergenicity is poorly understood. Here, we initially searched the Allergen Online database and did not find any allergic or cross-reactive proteins in porcine myoglobin (PM). In vitro simulated digestion demonstrated that PM did not exhibit notable acid-base resistance or anti-digestion capabilities. However, sensitization was observed in BALB/c mice, including a significant increase in specific antibodies and biomarkers for allergic reactions, as well as alterations in gut microbiome and serum metabolome. Interestingly, the intensity of sensitization exhibited a negative correlation with the purity of PM. 60% and 88% purities showed weaker sensitization compared to the ovalbumin control group. These allergic reactions were likely due to the non-myoglobin protein portion, highlighting the importance of purification processes and the urgent need to assess the allergenicity of this portion.

Next generation probiotics for human health: An emerging perspective

Over recent years, the scientific community has acknowledged the crucial role of certain microbial strains inhabiting the intestinal ecosystem in promoting human health, and participating in various beneficial functions for the host. These microorganisms are now referred to as next-generation probiotics and are currently considered as biotherapeutic products and food or nutraceutical supplements. However, the majority of next-generation probiotic candidates pose nutritional demands and exhibit high sensitivity towards aerobic conditions, leading to numerous technological hurdles in large-scale production. This underscores the need for the development of suitable delivery systems capable of enhancing the viability and functionality of these probiotic strains. Currently, potential candidates for next generation probiotics (NGP) are being sought among gut bacteria linked to health, which include strains from the genera Bacteroids, Faecalibacterium, Akkermansia and Clostridium. In contrast to Lactobacillus spp. and Bifidobacterium spp., NGP, particularly Bacteroids spp. and Clostridium spp., appear to exhibit greater ambiguity regarding their potential to induce infectious diseases. The present review provides a comprehensive overview of NGPs in terms of their health beneficial effects, regulation framework and risk assessment targeting relevant criteria for commercialization in food and pharmaceutical markets.

Associations of gut microbiota features and circulating metabolites with systemic inflammation in children

OBJECTIVE

Gut microbes and microbe-dependent metabolites (eg, tryptophan-kynurenine-serotonin pathway metabolites) have been linked to systemic inflammation, but the microbiota-metabolite-inflammation axis remains uncharacterised in children. Here we investigated whether gut microbiota features and circulating metabolites (both microbe-dependent and non-microbe-dependent metabolites) associated with circulating inflammation markers in children.

METHODS

We studied children from the prospective Gen3G birth cohort who had data on untargeted plasma metabolome (n=321 children; Metabolon platform), gut microbiota (n=147; 16S rRNA sequencing), and inflammation markers (plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1, and tumour necrosis factor-α) measured at 5-7 years. We examined associations of microbial taxa and metabolites-examining microbe-dependent and non-microbe-dependent metabolites separately-with each inflammatory marker and with an overall inflammation score (InfSc), adjusting for key confounders and correcting for multiple comparisons. We also compared the proportion of significantly associated microbe-dependent versus non-microbe-dependent metabolites, identified a priori (Human Microbial Metabolome Database), with each inflammation marker.

RESULTS

Of 335 taxa tested, 149 were associated (qFDR<0.05) with at least one inflammatory marker; 10 of these were robust to pseudocount choice. Several bacterial taxa involved in tryptophan metabolism were associated with inflammation, including kynurenine-degrading Ruminococcus, which was inversely associated with all inflammation markers. Of 1037 metabolites tested, 315 were previously identified as microbe dependent and were more frequently associated with PAI-1 and the InfSc than non-microbe dependent metabolites. In total, 87 metabolites were associated (qFDR<0.05) with at least one inflammation marker, including kynurenine (positively), serotonin (positively), and tryptophan (inversely).

CONCLUSION

A distinct set of gut microbes and microbe-dependent metabolites, including those involved in the tryptophan-kynurenine-serotonin pathway, may be implicated in inflammatory pathways in childhood.

Evaluation of efficacy and safety of Lacticaseibacillus rhamnosus LRa05 in the eradication of Helicobacter pylori: a randomized, double-blind, placebo-controlled trial

Aim

This study aims to evaluate the efficacy of Lacticaseibacillus rhamnosus LRa05 supplementation in enhancing Helicobacter pylori (H. pylori) eradication rate and alleviating the gastrointestinal side effects associated with bismuth quadruple therapy.

Methods

H. pylori-positive patients were randomized to receive levofloxacin-based bismuth quadruple therapy combined either probiotic LRa05 or a placebo for two weeks, followed by LRa05 (1 × 1010 CFU) or maltodextrin for the next two weeks. H. pylori infection was detected by 13C breath test pre- and post-treatment. Blood and stool samples were collected at week 0 and week 4 for routine and biochemical analysis, and serum inflammatory markers. Gastrointestinal symptoms were evaluated using the gastrointestinal symptom rating scale (GSRS). Intestinal microbiota was analyzed using 16S rRNA sequencing. The research was listed under the Chinese Clinical Trial Registry (ChiCTR2300072220), and written informed consent was obtained from all participants.

Results

The LRa05 group exhibited a trend toward higher H. pylori eradication rates (86.11%) compared to the placebo group (82.86%), though the difference was not statistically significant. Significant reductions in neutrophil count, alanine aminotransferase, aspartate aminotransferase, pepsinogen I, interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) (p < 0.05) suggest that LRa05 supplementation may mitigate inflammation, enhance liver function, and potential aid in early cancer prevention. GSRS symptom scores showed that LRa05 alleviated abdominal pain, acid reflux, bloating, and diarrhea, enhancing patient compliance. Furthermore, 16S rRNA sequencing showed that LRa05 countered the antibiotic-induced disruption of gut microbiota diversity, primarily by increasing beneficial bacteria.

Conclusion

Although LRa05 did not significantly improve the success rate of H. pylori eradication therapy, it has the potential to improve liver function and reduced levels of inflammatory markers such as IL-6 and TNF-α in the body, regulating the inflammatory response. In addition, it played a positive role in alleviating the adverse symptoms and gut microbiota disturbances caused by eradication therapy, providing a possible way to improve the overall health of patients and demonstrating promising clinical potential.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR2300072220.

Gut microbiome diversity within Clostridia is negatively associated with human obesity

Clostridia are abundant in the human gut and comprise families associated with host health such as Oscillospiraceae, which has been correlated with leanness. However, culturing bacteria within this family is challenging, leading to their detection primarily through 16S rRNA amplicon sequencing, which has a limited ability to unravel diversity at low taxonomic levels, or by shotgun metagenomics, which is hindered by its high costs and complexity. In this cross-sectional study involving 114 Colombian adults, we used an amplicon-based sequencing strategy with alternative markers-gyrase subunit B (gyrB) and DNA K chaperone heat protein 70 (dnaK)-that evolve faster than the 16S rRNA gene. Comparing the diversity and abundance observed with the three markers in our cohort, we found a reduction in the diversity of Clostridia, particularly within Lachnospiraceae and Oscillospiraceae among obese individuals [as measured by the body mass index (BMI)]. Within Lachnospiraceae, the diversity of Ruminococcus_A negatively correlated with BMI. Within Oscillospiraceae, the genera CAG-170 and Vescimonas also exhibited this negative correlation. In addition, the abundance of Vescimonas was negatively correlated with BMI. Leveraging shotgun metagenomic data, we conducted a phylogenetic and genomic characterization of 120 metagenome-assembled genomes from Vescimonas obtained from a larger sample of the same cohort. We identified 17 of the 72 reported species. The functional annotation of these genomes showed the presence of multiple carbohydrate-active enzymes, particularly glycosyl transferases and glycoside hydrolases, suggesting potential beneficial roles in fiber degradation, carbohydrate metabolism, and butyrate production.

IMPORTANCE

The gut microbiota is diverse across various taxonomic levels. At the intra-species level, it comprises multiple strains, some of which may be host-specific. However, our understanding of fine-grained diversity has been hindered by the use of the conserved 16S rRNA gene. While shotgun metagenomics offers higher resolution, it remains costly, may fail to identify specific microbes in complex samples, and requires extensive computational resources and expertise. To address this, we employed a simple and cost-effective analysis of alternative genetic markers to explore diversity within Clostridia, a crucial group within the human gut microbiota whose diversity may be underestimated. We found high intra-species diversity for certain groups and associations with obesity. Notably, we identified Vescimonas, an understudied group. Making use of metagenomic data, we inferred functionality, uncovering potential beneficial roles in dietary fiber and carbohydrate degradation, as well as in short-chain fatty acid production.

Interactions between the gut microbiome, associated metabolites and the manifestation and progression of heart failure with preserved ejection fraction in ZSF1 rats

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is associated with systemic inflammation, obesity, metabolic syndrome, and gut microbiome changes. Increased trimethylamine-N-oxide (TMAO) levels are predictive for mortality in HFpEF. The TMAO precursor trimethylamine (TMA) is synthesized by the intestinal microbiome, crosses the intestinal barrier and is metabolized to TMAO by hepatic flavin-containing monooxygenases (FMO). The intricate interactions of microbiome alterations and TMAO in relation to HFpEF manifestation and progression are analyzed here.

METHODS

Healthy lean (L-ZSF1, n = 12) and obese ZSF1 rats with HFpEF (O-ZSF1, n = 12) were studied. HFpEF was confirmed by transthoracic echocardiography, invasive hemodynamic measurements, and detection of N-terminal pro-brain natriuretic peptide (NT-proBNP). TMAO, carnitine, symmetric dimethylarginine (SDMA), and amino acids were measured using mass-spectrometry. The intestinal epithelial barrier was analyzed by immunohistochemistry, in-vitro impedance measurements and determination of plasma lipopolysaccharide via ELISA. Hepatic FMO3 quantity was determined by Western blot. The fecal microbiome at the age of 8, 13 and 20 weeks was assessed using 16s rRNA amplicon sequencing.

RESULTS

Increased levels of TMAO (+ 54%), carnitine (+ 46%) and the cardiac stress marker NT-proBNP (+ 25%) as well as a pronounced amino acid imbalance were observed in obese rats with HFpEF. SDMA levels in O-ZSF1 were comparable to L-ZSF1, indicating stable kidney function. Anatomy and zonula occludens protein density in the intestinal epithelium remained unchanged, but both impedance measurements and increased levels of LPS indicated an impaired epithelial barrier function. FMO3 was decreased (- 20%) in the enlarged, but histologically normal livers of O-ZSF1. Alpha diversity, as indicated by the Shannon diversity index, was comparable at 8 weeks of age, but decreased by 13 weeks of age, when HFpEF manifests in O-ZSF1. Bray-Curtis dissimilarity (Beta-Diversity) was shown to be effective in differentiating L-ZSF1 from O-ZSF1 at 20 weeks of age. Members of the microbial families Lactobacillaceae, Ruminococcaceae, Erysipelotrichaceae and Lachnospiraceae were significantly differentially abundant in O-ZSF1 and L-ZSF1 rats.

CONCLUSIONS

In the ZSF1 HFpEF rat model, increased dietary intake is associated with alterations in gut microbiome composition and bacterial metabolites, an impaired intestinal barrier, and changes in pro-inflammatory and health-predictive metabolic profiles. HFpEF as well as its most common comorbidities obesity and metabolic syndrome and the alterations described here evolve in parallel and are likely to be interrelated and mutually reinforcing. Dietary adaption may have a positive impact on all entities.

Licorice processing involving functions of Evodiae Fructus on liver inflammation and oxidative stress are associated with intestinal mucosal microbiota

Background

This study aimed to investigate the effects of licorice processing of different Evodiae Fructus (EF) specifications on liver inflammation and oxidative stress associated with the intestinal mucosal microbiota.

Materials and methods

The 25 Kunming mice were divided into control (MCN), raw small-flowered Evodiae Fructus (MRSEF), raw medium-flowered EF (MRMEF), licorice-processed small-flowered EF (MLSEF), and licorice-processed medium-flowered EF (MLSEF) groups. The EF intervention groups were given different specifications of EF extract solutions by gavage. After 21 days, indices of liver inflammation and oxidative stress and intestinal mucosal microbiota were measured in mice.

Results

Compared with the MCN, malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels were significantly increased in the MRMEF. Although the trends of oxidative stress and inflammatory indexes in the MLSEF and MLMEF were consistent with those in the raw EF groups, the changes were smaller than those in the raw EF groups. Compared to the raw EF groups, the MLSEF and MLMEF showed closer approximations of metabolic function to the MCN. The abundance of Corynebacterium in MRMEF was significantly lower than that in the MCN, and it was not significantly different from the MCN after licorice processing. The probiotic Candidatus Arthromitus was enriched in the MLSEF. The probiotic Lactobacillus was enriched in the MLMEF. Correlation analysis revealed significant negative correlations between IL-1β, some metabolic functions and Corynebacterium.

Conclusion

The effects of medium-flowered EF on oxidative stress and inflammatory factors in the liver of mice were stronger than those of small-flowered EF. The licorice processing can reduce this difference by modulating the abundance of Corynebacterium and intestinal mucosal metabolic function.

Soybean oil-based HFD induces gut dysbiosis that leads to steatosis, hepatic inflammation and insulin resistance in mice

High-fat diets (HFDs) shape the gut microbiome and promote obesity, inflammation, and liver steatosis. Fish and soybean are part of a healthy diet; however, the impact of these fats, in the absence of sucrose, on gut microbial dysbiosis and its association with liver steatosis remains unclear. Here, we investigated the effect of sucrose-free soybean oil-and fish oil-based high fat diets (HFDs) (SF-Soy-HFD and SF-Fish-HFD, respectively) on gut dysbiosis, obesity, steatosis, hepatic inflammation, and insulin resistance. C57BL/6 mice were fed these HFDs for 24 weeks. Both diets had comparable effects on liver and total body weights. But 16S-rRNA sequencing of the gut content revealed induction of gut dysbiosis at different taxonomic levels. The microbial communities were clearly separated, showing differential dysbiosis between the two HFDs. Compared with the SF-Fish-HFD control group, the SF-Soy-HFD group had an increased abundance of Bacteroidetes, Firmicutes, and Deferribacteres, but a lower abundance of Verrucomicrobia. The Clostridia/Bacteroidia (C/B) ratio was higher in the SF-Soy-HFD group (3.11) than in the SF-Fish-HFD group (2.5). Conversely, the Verrucomicrobiacae/S24_7 (also known as Muribaculaceae family) ratio was lower in the SF-Soy-HFD group (0.02) than that in the SF-Fish-HFD group (0.75). The SF-Soy-HFD group had a positive association with S24_7, Clostridiales, Allobaculum, Coriobacteriaceae, Adlercreutzia, Christensenellaceae, Lactococcus, and Oscillospira, but was related to a lower abundance of Akkermansia, which maintains gut barrier integrity. The gut microbiota in the SF-Soy-HFD group had predicted associations with host genes related to fatty liver and inflammatory pathways. Mice fed the SF-Soy-HFD developed liver steatosis and showed increased transcript levels of genes associated with de novo lipogenesis (Acaca, Fasn, Scd1, Elovl6) and cholesterol synthesis (Hmgcr) pathways compared to those in the SF-Fish-HFD-group. No differences were observed in the expression of fat uptake genes (Cd36 and Fabp1). The expression of the fat efflux gene (Mttp) was reduced in the SF-Soy-HFD group. Moreover, hepatic inflammation markers (Tnfa and Il1b) were notably expressed in SF-Soy-HFD-fed mice. In conclusion, SF-Soy-HFD feeding induced gut dysbiosis in mice, leading to steatosis, hepatic inflammation, and impaired glucose homeostasis.

The Effects of Caloric Restriction and Clinical Psychological Intervention on the Interplay of Gut Microbial Composition and Stress in Women

Both mental and metabolic disorders are steadily becoming more prevalent, increasing interest in non-pharmacological lifestyle interventions targeting both types of disorders. However, the combined effect of diet and psychological interventions on the gut microbiome and mental health outcomes remains underexplored. Thus, in this study, we randomized 41 women into two caloric restriction (CR) dietary groups, namely very-low-calorie diet (VLCD) and F.X. Mayr diet (FXM). The patients were then further randomized to either receive clinical psychological intervention (CPI) or no CPI. Blood and fecal samples were collected before and after two weeks of CR. Psychometric outcomes were assessed using the Perceived Stress Scale (PSS), Brief Symptom Index (BSI), and Burnout Dimension Inventory (BODI). Stool samples underwent 16S-rRNA sequencing. Upon two weeks of CR, α-diversity decreased overall and longitudinal PERMANOVA models revealed significant shifts in β-diversity according to diet, CPI, age, and body-mass-index. Furthermore, Agathobacter, Fusicatenibacter, and Subdoligranulum decreased in abundance. However, the Oscillibacter genus was enriched solely in FXM. CPI had a negligible effect on the microbiome. Dimension reduction models revealed clusters of taxa which distinctly associated with psychometric outcomes. Members of the Oscillospiraceae family were linked to favorable psychometric outcomes after two weeks of CR. Despite α-diversity reductions after CR, enrichment of Oscillospiraceae spp., solely seen in FXM, correlated with improved psychometric outcomes. This study suggests a promising direction for future interventions targeting mental health through gut microbial modulation.

Genetic Connectivity of Gut Microbiota and Oral Ulcers: A Mendelian Randomization Study

OBJECTIVES

The aim of this study was to reveal the relationship, if any, between gut microbiota and oral ulcers.

METHODS

We performed a 2-sample Mendelian randomization (MR) study to estimate the roles of gut microbiota in mouth ulcers. The summary datasets of gut microbiota were from the largest genome-wide association study (GWAS) conducted by MiBioGen, and data of mouth ulcers were obtained from UK Biobank. Random effect inverse variance-weighted, weighted median, MR Egger, simple mode and weighted mode were used to estimate the relationship. Sensitivity analyses were conducted to assess the heterogeneity and pleiotropy of instrumental variables. MR Steiger filtering was also applied to orient the causal direction.

RESULTS

Three gut microbiota taxa were positively associated with mouth ulcers: Holdemania (odds ratio [OR] = 1.005, 95% confidence interval [CI]: 1.001-1.009, P = .019), Oxalobacter (OR = 1.004, 95% CI: 1.000-1.007, P = .032), and Ruminococcaceae UCG011 (OR = 1.006, 95% CI: 1.001-1.011, P = .029), while 4 gut microbiota taxa were negatively associated with mouth ulcers: Actinobacteria (OR = 0.992, 95% CI: 0.985-1.000, P = .042), Lactobacillales (OR = 0.995, 95% CI: 0.990-1.000, P = .034), Oscillospira (OR = 0.990, 95% CI: 0.984-0.997, P = .007) and Phascolarctobacterium (OR = 0.992, 95% CI: 0.986-0.997, P = .003). Sensitivity analyses validated the robustness of the association in between.

CONCLUSIONS

This MR study identified a strong association between the quality of gut microbiota and oral ulcers. The findings are likely to expand the therapeutic targets for mouth ulcers.

Clostridioides difficile and Gut Microbiota: From Colonization to Infection and Treatment

Clostridioides difficile is the main causative agent of antibiotic-associated diarrhea (AAD) in hospitals in the developed world. Both infected patients and asymptomatic colonized individuals represent important transmission sources of C. difficile. C. difficile infection (CDI) shows a large range of symptoms, from mild diarrhea to severe manifestations such as pseudomembranous colitis. Epidemiological changes in CDIs have been observed in the last two decades, with the emergence of highly virulent types and more numerous and severe CDI cases in the community. C. difficile interacts with the gut microbiota throughout its entire life cycle, and the C. difficile's role as colonizer or invader largely depends on alterations in the gut microbiota, which C. difficile itself can promote and maintain. The restoration of the gut microbiota to a healthy state is considered potentially effective for the prevention and treatment of CDI. Besides a fecal microbiota transplantation (FMT), many other approaches to re-establishing intestinal eubiosis are currently under investigation. This review aims to explore current data on C. difficile and gut microbiota changes in colonized individuals and infected patients with a consideration of the recent emergence of highly virulent C. difficile types, with an overview of the microbial interventions used to restore the human gut microbiota.

Short-chain fatty acids ameliorate imiquimod-induced skin thickening and IL-17 levels and alter gut microbiota in mice: a metagenomic association analysis

Short-chain fatty acids (SCFAs) have been proposed to have anti-inflammatory effects and improve immune homeostasis. We aimed to examine the effects of SCFAs on skin phenotype, systemic inflammation, and gut microbiota in mice with psoriasis-like inflammation. Imiquimod (IMQ)-treated C57BL/6 mice served as the study model. We conducted a metagenomic association study of IMQ-mice treated with SCFAs or anti-IL-17 antibody using whole-genome shotgun sequencing. The associations among SCFA supplements, skin thickness, circulating inflammatory profiles, and fecal microbiota profiles were investigated. The microbiome study was performed using pipelines for phylogenetic analysis, functional gene analysis, and pathway analysis. In IMQ-treated mice, there were increases in skin thickness and splenic weight, as well as unique fecal microbial profiles. SCFAs ameliorated IMQ-induced skin thickening, splenic weight gain, and serum IL-17F levels, with results that were comparable with those receiving anti-IL-17 treatment. IMQ-treated mice receiving SCFAs had greater microbial diversity than mice treated with IMQ alone. SCFAs and anti-IL17 treatment were associated with alteration of gut microbiota, with increased prevalences of Oscillospiraceae and Lachnopiraceae and decreased prevalences of Muribaculaceae and Bacteroides, which have been predicted to be associated with increased glycan degradation, phenylalanine metabolism, and xylene degradation. SCFAs may mitigate IMQ-induced skin thickening and IL-17F levels and alter fecal microbiota profiles in IMQ-treated mice.

Gut microbiota as a residual risk factor causally influencing cardiac structure and function: Mendelian randomization analysis and biological annotation

Background

The gut microbiota (GM) is widely acknowledged to have a significant impact on cardiovascular health and may act as a residual risk factor affecting cardiac structure and function. However, the causal relationship between GM and cardiac structure and function remains unclear.

Objective

This study aims to employ a two-sample Mendelian randomization (MR) approach to investigate the causal association between GM and cardiac structure and function.

Methods

Data on 119 GM genera were sourced from a genome-wide association study (GWAS) meta-analysis (13,266 European participants) conducted by the MiBioGen consortium, while data on 16 parameters of cardiac structure and function were obtained from the UK Biobank's GWAS of cardiac magnetic resonance imaging (up to 41,135 European participants). Inverse variance weighted (IVW), MR-Egger, and weighted median (WM) methods were utilized for causal association assessments, with sensitivity analyses conducted to reinforce the findings. Finally, biological annotation was performed on the GWAS data of GM and cardiac phenotypes with causal associations to explore potential mechanisms.

Results

The MR analysis, predominantly based on the IVW model, revealed 93 causal associations between the genetically predicted abundance of 44 GM genera and 16 cardiac structure and function parameters. These associations maintained consistent directions in MR-Egger and WM models, with no evidence of pleiotropy detected. Biological annotations suggest that GM may influence cardiac structure and function through pathways involved in myocardial cell development, cardiac contractility, and apoptosis.

Conclusion

The MR analysis supports a causal association between certain abundances of genetically predicted GM and cardiac structure and function, suggesting that GM could be a residual risk factor impacting cardiac phenotypes.

Ameliorative effects of the mixed aqueous extract of Aurantii Fructus Immaturus and Magnoliae Officinalis Cortex on loperamide-induced STC mice

Aurantii fructus immaturus (AFI) and Magnoliae Officinalis Cortex (MOC) have been used to treat constipation in China for thousands of years. In this study, a mouse model of slow transit constipation (STC) was established by gavage of loperamide at a dose of 10 mg/kg bw/day for seven days. Seventy-two mice were randomly allocated to six groups (control, STC model, 3 g/kg AFI + MOC, 6 g/kg AFI + MOC, 12 g/kg AFI + MOC, and mosapride). A mixed aqueous extract of AFI and MOC was administered to the STC mice at the corresponding doses from the first day of modelling. Body weight, faecal water content, gastrointestinal transit time, and intestinal propulsion rate were evaluated. Serum levels of neurotransmitters and gastrointestinal hormones, colonic expression of aquaporins (AQP), and interstitial cells of Cajal (ICC) were assessed using ELISA, immunohistochemistry, and Western blot analysis. The abundance and diversity of the gut microbiota were analysed by 16S rRNA gene sequencing. The mixed aqueous extract significantly increased faecal water content and intestinal propulsion rate and shortened gastrointestinal transit time in STC mice. Furthermore, the administration of AFI and MOC significantly decreased serum vasoactive intestinal peptide (VIP), nitric oxide (NO), and somatostatin (SS) levels and increased serum motilin (MTL) levels in STC mice. The protein expression levels of AQP3 and AQP4 in the colon tissue of STC mice significantly decreased following AFI + MOC treatment, whereas those of AQP9 significantly increased. Moreover, the AFI + MOC treatment led to an increase in the number and functionality of ICCs. In addition, the relative abundances of Ruminococcus and Oscillospira increased in response to the administration of AFI + MOC in STC mice. In conclusion, the mixed aqueous extract of AFI and MOC promoted defaecation and increased intestinal mobility in STC mice. Its mechanisms of action involve modulatory effects on neurotransmitters, gastrointestinal hormones, AQPs, and ICCs. AFI + MOC treatment also improved the diversity and abundance of the gut microbiota in STC mice, particularly short-chain fatty acid-producing bacteria, which may play an important role in its beneficial effect on constipation.

Resistant starch and tannic acid synergistically ameliorated dextran sulfate sodium-induced ulcerative colitis, particularly in the distal colon

We previously confirmed that tannic acid could delay the metabolism of resistant starch in vitro, which suggested that tannic acid might deliver resistant starch to the distal colon in vivo. Accordingly, co-supplementation of resistant starch and tannic acid might be beneficial for keeping the distal colon healthy. Thus, this study compared the effects of resistant starch, tannic acid and their mixtures on dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. It was found that the mixtures had a more profound effect on ameliorating DSS-induced ulcerative colitis than resistant starch or tannic acid. In particular, the mixtures reversed the histology damage of the distal colon induced by DSS, while resistant starch or tannic acid alone did not. The mixtures also had a stronger ability to resist oxidative stress and inhibit inflammation in the distal colon. These results suggested that resistant starch and tannic acid synergistically alleviated DSS-induced ulcerative colitis, particularly in the distal colon. On the other hand, DSS decreased the production of short-chain fatty acids and induced significant microbial disorder, while the administration of resistant starch, tannic acid and their mixtures reversed the above shifts caused by DSS. In particular, the mixtures exhibited stronger prebiotic activity, as indicated by the microbial composition and production of short-chain fatty acids. Therefore, it was inferred that tannic acid delivered resistant starch to the distal colon of mice, and thus the mixtures had stronger prebiotic activity. As a result, the mixtures effectively alleviated ulcerative colitis in the whole colon.