Roseburia spp.: a marker of health?

Relationship between maternal-infant gut microbiota and infant food allergy

The gut microbiota plays a crucial role in food allergies. We sought to identify characteristics of the maternal gut microbiota in the third trimester and the infant gut microbiota in early life and the association of these microbiotas with infant food allergy. A total of 68 healthy pregnant women and their full-term newborns were selected from a cohort of 202 mother-infant pairs; among them, 24 infants had been diagnosed with food allergy within 1 year of age, whereas 44 infants were healthy without allergic symptoms. We collected 65 maternal fecal samples before delivery and 253 infant fecal samples at five time points following birth. Fecal samples were microbiologically analyzed using 16S rRNA gene sequencing. Holdemania abundance in the maternal gut microbiota in the third trimester was significantly higher in the non-allergy group than in the food allergy group (P = 0.036). In the infant gut microbiota, Holdemania was only found in meconium samples; its abundance did not differ significantly between the two groups. The change in the abundance of Actinobacteria over time differed between the non-allergy and food allergy groups (FA, P = 0.013; NA, P = 9.8 × 10-5), and the change in the abundance of Firmicutes over time differed significantly in the non-allergy group (P = 0.023). The abundances of genera Anaerotruncus, Roseburia, Ruminococcus, and Erysipelotricaceae were significantly different between the non-allergy and food allergy groups at different time points. Our results showed that maternal carriage of Holdemania during the third trimester strongly predicted the absence of food allergies in infants; there was no correlation between the presence of food allergies and the abundance of Holdemania in the infant gut microbiota. More dynamic fluctuations in phyla Actinobacteria and Firmicutes early in life protect against food allergy. Thus, the enrichment of the infant gut microbiota early in life with short-chain fatty acid-producing bacteria may be beneficial in preventing the development of food allergies in infants.

Microbial Interdomain Interactions Delineate the Disruptive Intestinal Homeostasis in Clostridioides difficile Infection

Clostridioides difficile infection (CDI) creates an imbalance in the intestinal microbiota due to the interaction of the components making up this ecosystem, but little is known about the impact of this disease on other microbial members. This work has thus been aimed at evaluating the taxonomic composition, potential gene-associated functions, virulence factors, and antimicrobial resistance profiles of gut microbiomes. A total of 48 DNA samples obtained from patients with health care facility-acquired (HCFO) and community-onset (CO) diarrhea were distributed in the following four groups according to CDI status: HCFO/+ (n = 13), HCFO/- (n = 8), CO/+ (n = 13), and CO/- (n = 14). These samples were subjected to shotgun metagenomics sequencing. Although the CDI groups' microbiota had microbiome alterations, the greatest imbalance was observed in the in the HCFO+/- groups, with an increase in common pathogens and phage populations, as well as a decrease in beneficial microorganisms that leads to a negative impact on some intestinal homeostasis-related metabolic processes. A reduction in the relative abundance of butyrate metabolism-associated genes was also detected in the HCFO groups (P < 0.01), with an increase in some virulence factors and antibiotic-resistance markers. A set of 51 differentially abundant species in the groups with potential association to CDI enabled its characterization, leading to their spatial separation by onset. Strong correlations between phages and some archaeal and bacterial phyla were identified. This highlighted the need to study the microbiota's various components since their imbalance is multifactorial, with some pathogens contributing to a greater or lesser extent because of their interaction with the ecosystem they inhabit. IMPORTANCE Clostridioides difficile infection represents a serious public health problem in different countries due to its high morbi-mortality and the high costs it represents for health care systems. Studies have shown the impact of this infection on intestinal microbiome homeostasis, mainly on bacterial populations. Our research provides evidence of the impact of CDI at both the compositional (bacteria, archaea, and viruses), and functional levels, allowing us to understand that the alterations of the microbiota occur systemically and are caused by multiple perturbations generated by different members of the microbiota as well as by some pathogens that take advantage of the imbalance to proliferate. Likewise, the 51 differentially abundant species in the study groups with potential association to CDI found in this study could help us envisage future treatments against this and other inflammatory diseases, improving future therapeutic options for patients.

The dietary treatment of histamine intolerance reduces the abundance of some histamine-secreting bacteria of the gut microbiota in histamine intolerant women. A pilot study

Restrictive diets for the treatment of different gastrointestinal disorders are reported to change the composition of intestinal microbiota. Recently, it has been proposed that individuals with histamine intolerance suffer from intestinal dysbiosis, having an overabundance of histamine-secreting bacteria, but how it is still unknown this state is affected by the usual dietary treatment of histamine intolerance [i.e., low-histamine diet and the supplementation with diamine oxidase (DAO) enzyme]. Thus, a preliminary study was carried out aiming to evaluate the potential changes on the composition of the intestinal microbiota in a group of five women diagnosed with histamine intolerance undergoing 9 months of the dietary treatment of histamine intolerance. After sequencing bacterial 16S rRNA genes (V3-V4 region) and analyzing the data using the EzBioCloud Database, we observed a reduction in certain histamine-secreting bacteria, including the genera Proteus and Raoultella and the specie Proteus mirabilis. Moreover, it was also observed an increase in Roseburia spp., a bacterial group frequently related to gut health. These changes could help to explain the clinical improvement experienced by histamine intolerant women underwent a dietary treatment.

Diet-induced microbial adaptation process of red deer (Cervus elaphus) under different introduced periods

Insufficient prey density is a major factor hindering the recovery of the Amur tiger (Panthera tigris altaica), and to effectively restore the Amur tiger, red deer (Cervus elaphus) was released into the Huangnihe National Nature Reserve of Northeast China as the main reinforcement. Differences in feeding and synergistic changes caused by the intestinal microbial communities could impact the adaptation of wildlife following reintroductions into field environments. We analyzed the foraging changes in shaping the intestinal microbial community of the red deer after being released to the Huangnihe National Nature Reserve and screened the key microbial flora of the red deer when processing complex food resources. The feeding and intestinal microbial communities of the red deer were analyzed by plant Deoxyribonucleic acid (DNA) barcoding sequencing and 16S rRNA high-throughput sequencing, respectively. The results showed that there were significant differences in food composition between wild and released groups [released in 2019 (R2): n = 5; released in 2021 (R0): n = 6]; the wild group fed mainly on Acer (31.8%) and Abies (25.6%), R2 fed mainly on Betula (44.6%), R0 had not formed a clear preferred feeding pattern but had certain abilities to process and adapt to natural foods. Firmicutes (77.47%) and Bacteroides (14.16%) constituted the main bacterial phylum of red deer, of which, the phylum Firmicutes was the key species of the introduced red deer for processing complex food resources (p < 0.05). The wild release process significantly changed the intestinal microbial structure of the red deer, making it integrate into the wild red deer. The period since release into the wild may be a key factor in reshaping the structure of the microbial community. This study suggested that the intestinal microbial structure of red deer was significantly different depending on how long since captive deer has been translocated. Individuals that have lived in similar environments for a long time will have similar gut microbes. This is the adaption process of the wildlife to natural environment after wild release, taking into account the gut microbes, and the feeding changes in shaping microbial communities can help introduced red deer match complex food resources and novel field environments.

Microbiota as a new pathogenetic factor in the development of chronic hyperuricemia and gout. Part I: the current state of the problem

The gut microbiota plays a key role in metabolism and immune regulation, and imbalance in microbial composition can contribute to various diseases. We present up-to-date data on the role of the gut microbiota in the occurrence of chronic hyperuricemia (HU) and gout, which is associated with the influence of the microbiota on the synthesis of purine-metabolizing enzymes and pro-inflammatory cytokines. It has been shown that the gut microbiota plays an important role in the pathophysiology of gout and can serve as a new target for therapy. Currently, the microbial index of gout is considered as a potential method for early diagnosis of the disease, possibly already at the preclinical stage. The gut microbiota can be a starting point in the study of the pathogenesis of HU and gout. This makes it necessary to assess the pathogenetic relationship between individual specific microorganisms, the microbiota as a whole, and the development of uric acid (UA) metabolism disorders that contribute to the onset of HU and its transformation into gout. It is assumed that this approach will provide a more complete understanding of the gut microbiota participation in the synthesis of UA and its extrarenal excretion, as well as of bacteria and bacterial enzymes that can be used as a probiotic coadjuvant for the treatment and prevention of gout.

Dietary Stevia Residue Extract Supplementation Improves Antioxidant Capacity and Intestinal Microbial Composition of Weaned Piglets

This study aimed to investigate the effects of diet supplementation with stevia residue extract (SRE) on growth performance, intestinal health, and antioxidant capacity of weaned piglets. A total of 144 weaned piglets (body weight 6.8 ± 0.5 kg) were randomly selected and allocated into four treatment groups with six replicates of six pigs/pen. The treatments consisted of a basal diet without SRE or basal diet supplemented with 100, 200, or 400 mg/kg SRE. The results showed that the addition of 200 mg/kg SRE to the diet significantly reduced (p < 0.05) the diarrhea rate of piglets compared with the control group. The supplementation of 400 mg/kg SRE in the diet significantly reduced the piglets’ serum MDA content and significantly increased (p < 0.05) the T-AOC, T-SOD, and GSH-PX activity in the serum. The dietary supplementation with 400 mg/kg SRE significantly increased (p < 0.05) the CAT and GSH-PX activity in the liver. Moreover, the supplementation of 400 mg/kg SRE in the diet significantly increased (p < 0.05) the relative abundance of Prevotellaceae (genus) and Roseburia (genus) beneficial bacteria compared to the control group. Spearman’s correlation analysis showed that Prevotella (genus) abundance was positively correlated with liver GSH-PX activity and acetic acid content of colon contents. In conclusion, the supplementation of 400 mg/kg SRE to the diet can improve piglet health by regulating antioxidant reduction homeostasis, which may also be associated with an increase in the relative numbers of potentially beneficial bacteria.

Nutrient composition influences the gut microbiota in chronic thoracic spinal cord-injured rats

Chronic spinal cord injury (SCI) results in an increased predisposition to various metabolic problems that can be exacerbated by consuming a diet rich in calories and saturated fat. In addition, gastrointestinal symptoms have been reported after SCI, including intestinal dysbiosis of the gut microbiome. The effects of both diet and SCI on the gut microbiome of adult male Long Evans rats euthanized 16 wk after injury were investigated. The rats were either thoracic spinal contused or received sham procedures. After 12 wk of either a low-fat or high-fat diet, cecal contents were analyzed, revealing significant microbial changes to every taxonomic level below the kingdom level. Shannon α diversity analyses demonstrated a significant difference in diversity between the groups based on the surgical condition of the rats. SCI produced a unique signature of changes in commensal bacteria that were significantly different than Sham. Specific changes in commensal bacteria as a result of diet manipulation had high fidelity with reports in the literature, such as Clostridia, Thiohalorhabdales, and Pseudomonadales. In addition, novel changes in commensal bacteria were identified that are unique dietary influences on SCI. Linear regression analysis on body fat and lean mass showed that a consequence of chronic SCI produces uncoupled associations between some commensal bacteria and body composition. In conclusion, despite tightly controlling the protein content and varying the carbohydrate and fat contents, Sham and SCI rats respond uniquely to diet. These data provide potential direction for therapeutic modulation of the microbiome to improve health and wellness following SCI.

Addition of Soluble Fiber in Low-Fat Purified Diets Maintains Cecal and Colonic Morphology, Modulates Bacterial Populations and Predicted Functions, and Improves Glucose Tolerance Compared with Traditional AIN Diets in Male Mice

Background

Purified diets (PDs) contain refined ingredients with one main nutrient, allowing for greater control relative to grain-based diets (GBDs), which contain unrefined grains and animal byproducts. Traditional PDs like the American Institute of Nutrition (AIN)-76A (76A) and AIN-93G (93G) can negatively impact metabolic and gut health when fed long term, in part due to lower total fiber, no soluble fiber, and higher sucrose content.

Objective

Two studies were conducted to determine how PDs with reduced sucrose and increased fiber (soluble and insoluble) influence metabolic and gut health in mice compared with traditional AIN PDs or GBDs.

Methods

In study 1, C57Bl/6N mice (n = 75) consumed a GBD [LabDiet 5002 (5002)], 76A, 93G, or 2 PDs with reduced sucrose and higher fiber for 88 d. Body composition and metabolic parameters were assessed. In study 2, C57Bl/6N mice (n = 54) consumed either 2 GBDs (LabDiet 5001 or 5002) or PDs with different types/levels of fiber for 14 d. Microbiome alterations and predicted functional metagenomic changes were measured.

Results

The PD with 75 g cellulose and 25 g inulin per 4084 kcals marginally influenced body weight and adiposity, but improved glucose tolerance relative to 93G (P = 0.0131) and 76A (P = 0.0014). Cecal and colonic weights were lower in mice fed cellulose-based PDs compared with those fed GBDs and soluble-fiber PDs. Soluble-fiber PDs reduced alpha diversity and showed similar beta diversity, which differed from cellulose-based PDs and GBDs. Certain genera associated with improved gut health such as Bifidobacteria and Akkermansia were significantly elevated by soluble-fiber PDs (P ≤ 0.01). Metabolic pathways related to carbohydrate and fatty acid metabolism were affected by PDs.

Conclusions

PDs formulated with lower sucrose and increased fiber content, particularly soluble fiber, blunted elevations in metabolic parameters and favorably impacted the microbiota and metagenome in C57BL/6N mice.

Probiotic effects of Lacticaseibacillus rhamnosus 1155 and Limosilactobacillus fermentum 2644 on hyperuricemic rats

Hyperuricemia is the main cause of gout and involved in the occurrence of multiple diseases, such as hypertension, metabolic disorders and chronic kidney disease. Emerging evidence suggests that lactic acid bacteria (LAB) have shown the beneficial effects on the prevention or treatment of hyperuricemia. In this study, the urate-lowering effect of two LAB strains, Lacticaseibacillus rhamnosus 1155 (LR1155) and Limosilactobacillus fermentum 2644 (LF2644) on hyperuricemic rats were investigated. A hyperuricemic rat model was induced by the intragastric treatment of potassium oxonate, combined with a high purine diet. The oral administration of LR1155, LF2644, or a combination of LR1155 and LF2644 for 4 weeks significantly prevented the rise of the serum uric acid (UA) induced by hyperuricemia. LR1155 and LF2644 significantly elevated the fecal UA levels, increased the UA content and up-regulated gene expression of UA transporter, ATP-binding cassette subfamily G-2 (ABCG2), in colon and jejunum tissues, suggesting the accelerated UA excretion from the intestine. Besides, LR1155 significantly inhibited the activity of xanthine oxidase (XOD) in liver and serum, benefited the reduce of UA production. In addition, LF2644 strengthened the gut barrier functions through an up-regulation of the gene expressions for occluding and mucin2, accompanied with the reduced inflammatory indicators of lipopolysaccharide (LPS) and interleukin-1β (IL-1β) in hyperuricemic rat. Moreover, using 16s rDNA high-throughput sequencing of feces, LR1155 was shown to improve the hyperuricemia induced gut microbial dysbiosis. The genera Roseburia, Butyricicoccus, Prevotella, Oscillibacter, and Bifidobacterium may associate with the effect of LR1155 on microbiota in hyperuricemic rats. Collectively, the results indicated that LR1155 and LF2644 exhibit urate-lowering effects and could be used alone or in combination as a new adjuvant treatment for hyperuricemia.

Effect of a Proton Pump Inhibitor on the Duodenum Microbiome of Gastric Ulcer Patients

The gut microbiota are regarded as a functional organ that plays a substantial role in human health and disease. Proton pump inhibitors (PPIs) are widely used in medicine but can induce changes in the overall gut microbiome and cause disease-associated dysbiosis. The microbiome of the duodenum has not been sufficiently studied, and the effects of PPIs on the duodenal microbiome are poorly understood. In this study, we investigated the effect of PPI administration on duodenum microbiota in patients with a gastric ulcer. A total of 12 gastric ulcer patients were included, and PPI (Ilaprazole, Noltec^®, 10 mg) was prescribed in all patients for 4 weeks. A total of 17 samples from the second portion of the duodenum were analyzed. Microbiome compositions were assessed by sequencing the V3–V4 region of the 16s rRNA gene (Miseq). Changes in microbiota compositions after 4 weeks of PPI treatment were analyzed. a-Diversity was higher after PPI treatment (p = 0.02, at Chao1 index), and β-diversity was significantly different after treatment (p = 0.007). Welch’s t-test was used to investigate changes in phyla, genus, and species level, and the abundance of Akkermansia muciniphila, belonging to the phylum Verrucomicrobia, and Porphyromonas endodontalis, belonging to the phylum Bacteroidetes, was significantly increased after treatment (p = 0.044 and 0.05). PPI administration appears to induce duodenal microbiome dysbiosis while healing gastric ulcers. Further large-scale studies on the effects of PPIs on the duodenal microbiome are required.

Genetic analysis of seed traits in Sorghum bicolor that affect the human gut microbiome

Prebiotic fibers, polyphenols and other molecular components of food crops significantly affect the composition and function of the human gut microbiome and human health. The abundance of these, frequently uncharacterized, microbiome-active components vary within individual crop species. Here, we employ high throughput in vitro fermentations of pre-digested grain using a human microbiome to identify segregating genetic loci in a food crop, sorghum, that alter the composition and function of human gut microbes. Evaluating grain produced by 294 sorghum recombinant inbreds identifies 10 loci in the sorghum genome associated with variation in the abundance of microbial taxa and/or microbial metabolites. Two loci co-localize with sorghum genes regulating the biosynthesis of condensed tannins. We validate that condensed tannins stimulate the growth of microbes associated with these two loci. Our work illustrates the potential for genetic analysis to systematically discover and characterize molecular components of food crops that influence the human gut microbiome.

Diet affects the human gut microbiome, but studies linking crop genetics to seed traits that influence the human gut microbiome are lacking. Here, the authors develop an in vitro microbiome screening method and reveal the association between sorghum genes regulating condensed tannin biosynthesis and human gut microbiome.

Microbial characteristics of dental caries in HIV positive individuals

Background

Dental caries is a multifactorial disease that affects many people. Even though microorganisms play a crucial role in causing dental caries, diagnosis is routinely macroscopic. In order to improve early detection especially in HIV patients who are disproportionately affected, there is need to reconcile the macroscopic and microscopic characteristics of dental caries. Therefore, the aim of this study was to characterize the oral microbiota profile along the decayed, missing, filled teeth (DMFT) index using amplicon sequencing data.

Methods

Amplicon sequencing of the V6-V8 region of the 16S rRNA gene was done on DNA recovered from whole unstimulated saliva of 59 HIV positive and 29 HIV negative individuals. The microbial structure, composition and co-occurrence networks were characterized using QIIME-2, Phyloseq, Microbiome-1.9.2 and Metacoder in R.

Results

We characterized the oral microbiota into 2,093 operational taxonomic units (OTUs), 21 phyla and 239 genera from 2.6 million high quality sequence reads. While oral microbiota did not cluster participants into distinct groups that track with the DMFT index, we observed the following: (a) The proportion of accessory microbiota was highest in the high DMFT category while the core size (∼50% of richness) remained relatively stable across all categories. (b) The abundance of core genera such as Stomatobaculum, Peptostreptococcus and Campylobacter was high at onset of dental caries, (c) A general difference in oral microbial biomass. (d) The onset of dental caries (low DMFT) was associated with significantly lower oral microbial entropy.

Conclusions

Although oral microbial shifts along the DMFT index were not distinct, we demonstrated the potential utility of microbiota dynamics to characterize oral disease. Therefore, we propose a microbial framework using the DMFT index to better understand dental caries among HIV positive people in resource limited settings.

Infection with white spot syndrome virus affects the microbiota in the stomachs and intestines of kuruma shrimp

Maintaining eubiosis of the gastrointestinal (GI) microbiota is essential for animal health. White spot syndrome virus (WSSV) is the most lethal viral pathogen because it causes extremely high mortality in shrimp farming. However, it remains poorly understood how WSSV infection affects the microbiota in different regions of the GI tract of shrimp. In the present study, we established an experimental model of kuruma shrimp (Marsupenaeus japonicus) infection with WSSV and then investigated the effects of WSSV infection on the microbiota in the cardiac stomach, pyloric stomach, and intestines using metataxonomics. We identified 34 phyla and 576 genera of bacteria collectively. At the phylum level, Proteobacteria and Firmicutes were the most abundant in all the three GI segments. The WSSV infection decreased microbial diversity to a different extent in the stomachs and in a time-dependent manner. The infection with WSSV affected the microbiota composition in the two stomachs, but not the intestines. Firmicutes increased significantly, while Actinobacteria, Bacteroidetes, and Cyanobacteria decreased in the two stomachs of the WSSV-infected shrimp. At the genus level, Trichococcus and Vibrio increased, but Bradyrhizobium and Roseburia decreased in the cardiac stomach of the WSSV-infected shrimp. Trichococcus and Photobacterium increased in the pyloric stomach. Although Vibrio showed a slight downward trend, Aliivibrio (formerly Vibrio) increased in the pyloric stomach. Thiothrix, Fusibacter, and Shewanella decreased in the pyloric stomach, but no significant differences in these genera were detected in the cardiac stomach. Analysis of the predicted functions of the GI microbiota indicated that the WSSV infection resulted in losses of some microbiota functions. The new information from this study may help better understand the bacteria-virus interaction in the GI tract of shrimp and other crustacean species, and inform pathogen prevention/control and sustainable aquaculture production.

Microbiota dysbiosis in primary Sjögren's syndrome and the ameliorative effect of hydroxychloroquine

The human microbiome plays an important role in autoimmune diseases. However, there is limited knowledge regarding the microbiota in individuals with primary Sjögren's syndrome (pSS). Here, we perform 16S ribosomal RNA gene sequencing of fecal, oral, and vaginal samples from a cohort of 133 individuals with pSS, 56 with non-pSS, and 40 healthy control (HC) individuals. Dysbiosis in the gut, oral, and vaginal microbiome is evident in patients with pSS, and oral samples demonstrate the greatest extent of microbial variation. Multiple key indicator bacteria and clinical characteristics are identified across different body sites, implying that microbial dysbiosis has important roles in the pathogenesis of pSS. Furthermore, we observe pSS-like dysbiosis in individuals with pre-clinical pSS or non-pSS-related disease, revealing that microbial shifts could appear prior to pSS. After hydroxychloroquine (HCQ) treatment, microbial dysbiosis in individuals with pSS is partially resolved, although the microbiota composition remain disordered. These results contribute to the overall understanding of the relationship between the microbiome and pSS.

Gut microbiota dysbiosis in 4- to 6-year-old children with obstructive sleep apnea-hypopnea syndrome

OBJECTIVE

Several experiments on animals have reported the relationship between obstructive sleep apnea-hypopnea syndrome (OSAHS) and gut microbiota. We investigated the gut microbiota composition of children aged 4-6 years with OSAHS to complement the pathogenesis and clinical screening methods of OSAHS.

METHODS

We collected feces from 43 children with OSAHS and 45 controls aged 4-6 years. We extracted total bacterial DNA from feces and analyzed the composition of gut microbiota through 16S ribosomal RNA sequencing.

RESULTS

There were significant differences in bacteria producing short-chain fatty acids (SCFAs) between OSAHS children and controls, including Faecalibacterium, Roseburia, and a member of Ruminococcaceae. A gut microbiota model for pediatric OSAHS screening showed that the receiver operating characteristic-area under the curve (ROC-AUC) was 0.794 with 79.1% and 80.0% sensitivity and specificity, respectively. Functional analysis of the gut microbiota revealed several alterations in metabolism.

CONCLUSION

The composition of gut microbiota in OSAHS children is partially changed. The altered intestinal flora may provide a new screening method for the diagnosis of children with OSAHS. The prediction of gut microbiota function suggests that intestinal metabolic function may be altered in OSAHS children.

Roseburia hominis Alleviates Neuroinflammation via Short-Chain Fatty Acids through Histone Deacetylase Inhibition

SCOPE

The gut microbiota plays a prominent role in gut-brain interactions and gut dysbiosis is involved in neuroinflammation. However, specific probiotics targeting neuroinflammation need to be explored. In this study, the antineuroinflammatory effect of the potential probiotic Roseburia hominis (R. hominis) and its underlying mechanisms is investigated.

METHODS AND RESULTS

First, germ-free (GF) rats are orally treated with R. hominis. Microglial activation, proinflammatory cytokines, levels of short-chain fatty acids, depressive behaviors, and visceral sensitivity are assessed. Second, GF rats are treated with propionate or butyrate, and microglial activation, proinflammatory cytokines, histone deacetylase 1 (HDAC1), and histone H3 acetyl K9 (Ac-H3K9) are analyzed. The results show that R. hominis administration inhibits microglial activation, reduces the levels of IL-1α, INF-γ, and MCP-1 in the brain, and alleviates depressive behaviors and visceral hypersensitivity in GF rats. Moreover, the serum levels of propionate and butyrate are increased significantly in the R. hominis-treated group. Propionate or butyrate treatment reduces microglial activation, the levels of proinflammatory cytokines and HDAC1, and promotes the expression of Ac-H3K9 in the brain.

CONCLUSION

These findings suggest that R. hominis alleviates neuroinflammation by producing propionate and butyrate, which serve as HDAC inhibitors. This study provides a potential psychoprobiotic to reduce neuroinflammation.

A Placebo-controlled double-blinded test of the biodiversity hypothesis of immune-mediated diseases: Environmental microbial diversity elicits changes in cytokines and increase in T regulatory cells in young children

BACKGROUND

According to the biodiversity hypothesis of immune-mediated diseases, lack of microbiological diversity in the everyday living environment is a core reason for dysregulation of immune tolerance and - eventually - the epidemic of immune-mediated diseases in western urban populations. Despite years of intense research, the hypothesis was never tested in a double-blinded and placebo-controlled intervention trial.

OBJECTIVE

We aimed to perform the first placebo-controlled double-blinded test that investigates the effect of biodiversity on immune tolerance.

METHODS

In the intervention group, children aged 3-5 years were exposed to playground sand enriched with microbially diverse soil, or in the placebo group, visually similar, but microbially poor sand colored with peat (13 participants per treatment group). Children played twice a day for 20 min in the sandbox for 14 days. Sand, skin and gut bacterial, and blood samples were taken at baseline and after 14 days. Bacterial changes were followed for 28 days. Sand, skin and gut metagenome was determined by high throughput sequencing of bacterial 16 S rRNA gene. Cytokines were measured from plasma and the frequency of blood regulatory T cells was defined as a percentage of total CD3 +CD4 + T cells.

RESULTS

Bacterial richness (P < 0.001) and diversity (P < 0.05) were higher in the intervention than placebo sand. Skin bacterial community, including Gammaproteobacteria, shifted only in the intervention treatment to resemble the bacterial community in the enriched sand (P < 0.01). Mean change in plasma interleukin-10 (IL-10) concentration and IL-10 to IL-17A ratio supported immunoregulation in the intervention treatment compared to the placebo treatment (P = 0.02). IL-10 levels (P = 0.001) and IL-10 to IL-17A ratio (P = 0.02) were associated with Gammaproteobacterial community on the skin. The change in T_reg frequencies was associated with the relative abundance of skin Thermoactinomycetaceae 1 (P = 0.002) and unclassified Alphaproteobacteria (P < 0.001). After 28 days, skin bacterial community still differed in the intervention treatment compared to baseline (P < 0.02).

CONCLUSIONS

This is the first double-blinded placebo-controlled study to show that daily exposure to microbial biodiversity is associated with immune modulation in humans. The findings support the biodiversity hypothesis of immune-mediated diseases. We conclude that environmental microbiota may contribute to child health, and that adding microbiological diversity to everyday living environment may support immunoregulation.

Intermittent fasting positively modulates human gut microbial diversity and ameliorates blood lipid profile

Aim

The aim was to evaluate the impact of intermittent fasting (IF) on human body mass index (BMI) and serum lipid profile thorough constructive rectification of gut microbiota.

Methods and results

Fourteen healthy women and thirty-one men were included in the study. Their blood and fecal samples were collected before and at the end of the study. Blood parameters, anthropometric values, and gut microbiology were noted to investigate the impact of intermittent fasting (IF) on human gut microbiota and physiology. Our data revealed that IF reduces the body weight and improves blood lipid profile, such as increasing high-density lipoprotein (HDL) and decreasing total cholesterol, triglycerides, and low- and very low-density lipoprotein levels. IF also decreases culturable aerobic bacterial count and increased fungal count. It was also found that the gut metagenome is altered considerably after IF. The human fecal bacterial diversity exhibited significant changes in decreased overall bacterial population, increased bacterial diversity (alpha diversity), and promoted evenness within the bacterial population at the species level. Anti-inflammatory bacteria Lactobacillus and Bifidobacterium were favorably increased, while pathogenic bacteria were decreased.

Conclusion

Collectively, these results indicated that IF could improve lipid profile and body weight in humans, and the potential mechanisms might be via regulating gut microbiota.

Significance and impact of the study

We demonstrated for the first time that IF improved body weight and blood lipid profile, indicating that IF could mitigate gut microbiota in humans.

Microbiota Dysbiosis in Parkinson Disease—In Search of a Biomarker

Numerous studies have highlighted the role of the gastrointestinal system in Parkinson disease pathogenesis. It is likely triggered by proinflammatory markers produced by specific gut bacteria. This review’s aim is to identify gut bacterial biomarkers of Parkinson disease. A comprehensive search for original research papers on gut microbiota composition in Parkinson disease was conducted using the PubMed, Embase, and Scopus databases. Research papers on intestinal permeability, nasal and oral microbiomes, and interventional studies were excluded. The yielded results were categorized into four groups: Parkinson disease vs. healthy controls; disease severity; non-motor symptoms; and clinical phenotypes. This review was conducted in accordance with the PRISMA 2020 statement. A total of 51 studies met the eligibility criteria. In the Parkinson disease vs. healthy controls group, 22 bacteria were deemed potentially important. In the disease severity category, two bacteria were distinguished. In the non-motor symptoms and clinical phenotypes categories, no distinct pathogen was identified. The studies in this review report bacteria of varying taxonomic levels, which prevents the authors from reaching a clear conclusion. Future research should follow a unified methodology in order to identify potential biomarkers for Parkinson disease.

Theabrownin isolated from Pu-erh tea regulates Bacteroidetes to improve metabolic syndrome of rats induced by high-fat, high-sugar and high-salt diet

BACKGROUND

Theabrownin (TB), a high macromolecular compound and a characteristic component of Pu-erh tea, is able to markedly regulate blood lipid and glucose metabolism. We hypothesized that TB could ameliorate metabolic syndrome induced by high-fat, high-sugar and high-salt diet (HFSSD).

RESULTS

To test these hypotheses, we fed rats with HFSSD and administered a gavage of TB. HFSSD successfully induced metabolic syndrome in rats. TB significantly improved serum lipid status, prevented obesity and fasting blood glucose (FBG) and glycosylated hemoglobin (GHbAIc) in rats. After TB intervention, Firmicutes/Bacteroides (F/B) ratio was greatly reduced and showed a dose-effect relationship. TB promoted the reproduction of Bacteroidetes such as prevotella_sp._CAG:1031, prevotella_sp._MGM2 and Bacteroides_sartorii, and inhibited the reproduction of Firmicutes such as roseburia_sp._1XD42-69 and roseburia_sp._831b.

CONCLUSION

In HFSSD mode, prevotella_sp._CAG:1031 was one of the main dominant characteristic bacteria of TB targeting regulation, while roseburia_sp._1XD42-69 mainly inhibitory intestinal bacteria, which help to reduce body weight, TG and blood sugar levels of HFSSD rats. Glycerophospholipid metabolism, arachidonic acid metabolism, glycolysis/gluconeogenesis and insulin resistance were the critical pathway. TB has a high application potential in reducing the risk of metabolic diseases. © 2022 Society of Chemical Industry.

Gut Microbiota Composition in Prediabetes and Newly Diagnosed Type 2 Diabetes: A Systematic Review of Observational Studies

Evidence of gut microbiota involvement in regulating glucose metabolism and type 2 diabetes mellitus (T2DM) progression is accumulating. The understanding of microbial dysbiosis and specific alterations of gut microbiota composition that occur during the early stages of glucose intolerance, unperturbed by anti-diabetic medications, is especially essential. Hence, this systematic review was conducted to summarise the existing evidence related to microbiota composition and diversity in individuals with prediabetes (preDM) and individuals newly diagnosed with T2DM (newDM) in comparison to individuals with normal glucose tolerance (nonDM). A systematic search of the PubMed, MEDLINE and CINAHL databases were conducted from inception to February 2021 supplemented with manual searches of the list of references. The primary keywords of “type 2 diabetes”, “prediabetes”, “newly-diagnosed” and “gut microbiota” were used. Observational studies that conducted analysis of the gut microbiota of respondents with preDM and newDM were included. The quality of the studies was assessed using the modified Newcastle-Ottawa scale by independent reviewers. A total of 18 studies (5,489 participants) were included. Low gut microbial diversity was generally observed in preDM and newDM when compared to nonDM. Differences in gut microbiota composition between the disease groups and nonDM were inconsistent across the included studies. Four out of the 18 studies found increased abundance of phylum Firmicutes along with decreased abundance of Bacteroidetes in newDM. At the genus/species levels, decreased abundance of Faecalibacterium prausnitzii, Roseburia, Dialister, Flavonifractor, Alistipes, Haemophilus and Akkermansia muciniphila and increased abundance of Lactobacillus, Streptococcus, Escherichia, Veillonella and Collinsella were observed in the disease groups in at least two studies. Lactobacillus was also found to positively correlate with fasting plasma glucose (FPG), HbA1c and/or homeostatic assessment of insulin resistance (HOMA-IR) in four studies. This renders a need for further investigations on the species/strain-specific role of endogenously present Lactobacillus in glucose regulation mechanism and T2DM disease progression. Differences in dietary intake caused significant variation in specific bacterial abundances. More studies are needed to establish more consistent associations, between clinical biomarkers or dietary intake and specific gut bacterial composition in prediabetes and early T2DM.

Interplay between Intestinal Bacterial Communities and Unicellular Parasites in a Morbidly Obese Population: A Neglected Trinomial

Obesity is an epidemic causing a metabolic health crisis. Herein, the interactions between the gut prokaryotic and eukaryotic communities, metabolic comorbidities and diet were studied. Stool samples from 56 subjects, 47 with type III obesity and 9 with type II obesity and cardiovascular risk or metabolic disease, were assessed for the richness, diversity and ecology of the bacterial gut community through metagenomics, together with the study of the presence of common unicellular eukaryote parasites (Blastocystis sp., Dientamoeba fragilis and Giardia intestinalis) by qPCR. Clinical information regarding metabolic comorbidities and non-alcoholic hepatic fatty liver disease was gathered. To assess the quality of the patients’ diet, each participant filled in three dietary questionnaires. The most prevalent parasite Blastocystis sp. (46.4%), together with D. fragilis (8.9%), was found to be associated with higher mean diversity indexes regarding non-colonized subjects; the opposite of that which was observed in those with G. intestinalis (16.1%). In terms of phyla relative abundance, with Blastocystis sp. and D. fragilis, very slight differences were observed; on the contrary, G. intestinalis was related to an increase in Bacteroidetes and Proteobacteria, and a decrease in Firmicutes and Actinobacteria, presenting the lowest Firmicutes/Bacteroidetes ratio. At genus level, Blastocystis sp. and/or D. fragilis was accompanied with an increase in Lactobacillus spp., and a decrease in Akkermansia spp., Bifidobacterium spp. and Escherichia spp., while G. intestinalis was associated with an increase in Bacteroides spp., and a decrease in Faecalibacterium spp., Prevotella spp. and Lactobacillus spp., and the highest Bacteroides spp./Prevotella spp. ratio. Participants with non-alcoholic hepatic fatty liver presented a higher Firmicutes/Bacteroidetes ratio, and those with type 2 diabetes displayed a significantly lower Faecalibacterium spp./Escherichia spp. ratio, due to an overrepresentation of the genus Escherichia spp. The presence of parasites was associated with variations in the richness, diversity and distribution of taxa in bacterial communities, confirming a gain in diversity associated with Blastocystis sp. and providing different functioning of the microbiota with a potential positive effect on comorbidities such as type 2 diabetes, insulin resistance and metabolic syndrome. Future basic and clinical studies should assess the beneficial or pathogenic effect of these eukaryotes on obese subjects and focus on deciphering whether they may imply a healthier metabolic profile.

Effects of probiotics on gastric microbiota and its precombination with quadruple regimen for Helicobacter pylori eradication

OBJECTIVES

This study aimed to assess the efficacy and safety of probiotics for Helicobacter pylori (H. pylori) eradication therapy as well as their effects on gastric microbiota.

METHODS

Patients who had failed H. pylori eradication therapy for at least twice were prospectively enrolled during March 2019 and March 2021. A 2-week administration of compound Lactobacillus acidophilus probiotic (1 g thrice daily) followed by a 10-day quadruple bismuth-containing H. pylori eradication therapy was administrated. Endoscopy was performed, and gastric biopsy samples were obtained for drug sensitivity testing and 16S rRNA gene sequencing before and after probiotic treatment. Eradication was evaluated by the ¹³ C-urea breath test at least 4 weeks after treatment completion. Adverse events (AEs) were recorded.

RESULTS

Thirty-seven patients were included. Probiotic supplementation had no effects on the diversity, community structure, and composition of gastric microbiota and no inhibition on H. pylori activity. However, it increased some of the beneficial bacteria such as Blautia, Dorea, and Roseburia (P < 0.05). The overall eradication rate was 97.3% (95% confidence interval [CI] 91.8%-100%). AEs, mainly dizziness, nausea, diarrhea, and chest distress, were detected in six individuals, all of which were resolved upon cessation of antibiotic administration. Dyspeptic symptoms were improved after probiotic supplementation and at treatment completion (both P < 0.001).

CONCLUSIONS

H. pylori-infected individuals might benefit from probiotics followed by a quadruple bismuth-containing eradication therapy. Further studies with large sample sizes are warranted.

A Pilot Study: Favorable Effects of Clostridium butyricum on Intestinal Microbiota for Adjuvant Therapy of Lung Cancer

Probiotics as medications have previously been shown to change intestinal microbial characteristics, potentially influencing cancer therapy efficacy. Patients with non-squamous non-small cell lung cancer (NS-NSCLC) treated by bevacizumab plus platinum-based chemotherapy were randomized to obtain Clostridium butyricum supplement (CBS) or receive a placebo as adjuvant therapy. Clinical efficacy and safety were assessed using progression-free survival (PFS), overall survival (OS), and adverse events (AE). Intestinal microbiota was longitudinally explored between CBS and placebo groups over time. Patients who took CBS had significantly decreased bacterial richness and abundance, as well as increased the total richness of the genus Clostridium, Bifidobacterium, and Lactobacillus compared to the placebo group (p < 0.05). Beta diversity and the interactional network of intestinal microbiota were distinctly different between CBS and placebo group. However, there were no significant variations between them in terms of microbial taxonomical taxa and alpha diversity. The potential opportunistic pathogen Shewanella was still detectable after treatment in the placebo group, while no distinguishing microbial markers were found in the CBS group. In terms of clinical efficacy, the CBS group had a significantly reduced AE compare to the placebo group (p < 0.05), although no significantly longer PFS and OS. Therefore, favorable modifications in intestinal microbiota and significant improvements in drug safety make probiotics be promising adjunctive therapeutic avenues for lung cancer treatment.

Maternal Acetate Supplementation Reverses Blood Pressure Increase in Male Offspring Induced by Exposure to Minocycline during Pregnancy and Lactation

Emerging evidence supports that hypertension can be programmed or reprogrammed by maternal nutrition. Maternal exposures during pregnancy, such as maternal nutrition or antibiotic use, could alter the offspring’s gut microbiota. Short-chain fatty acids (SCFAs) are the major gut microbiota-derived metabolites. Acetate, the most dominant SCFA, has shown its antihypertensive effect. Limited information exists regarding whether maternal acetate supplementation can prevent maternal minocycline-induced hypertension in adult offspring. We exposed pregnant Sprague Dawley rats to normal diet (ND), minocycline (MI, 50 mg/kg/day), magnesium acetate (AC, 200 mmol/L in drinking water), and MI + AC from gestation to lactation period. At 12 weeks of age, four groups (n = 8/group) of male progeny were sacrificed. Maternal acetate supplementation protected adult offspring against minocycline-induced hypertension. Minocycline administration reduced plasma acetic acid level, which maternal acetate supplementation prevented. Additionally, acetate supplementation increased the protein level of SCFA receptor G protein-coupled receptor 41 in the offspring kidneys. Further, minocycline administration and acetate supplementation significantly altered gut microbiota composition. Maternal acetate supplementation protected minocycline-induced hypertension accompanying by the increases in genera Roseburia, Bifidobacterium, and Coprococcus. In sum, our results cast new light on targeting gut microbial metabolites as early interventions to prevent the development of hypertension, which could help alleviate the global burden of hypertension.

Maternal Dietary Forsythia suspensa Extract Supplementation Induces Changes in Offspring Antioxidant Status, Inflammatory Responses, Intestinal Development, and Microbial Community of Sows

This experiment aims to investigate the effect of maternal diet supplemented with Forsythia suspensa extract (FSE) on the performance, antioxidant status, inflammatory responses, intestinal development, and microbial community of sows. A total of 24 gestating sows (Landrace × Yorkshire) were assigned to 2 treatments with 12 sows per treatment. From d 107 of gestation to d 21 of lactation, sows were supplemented with a basal diet as control (CON) or an FSE diet (basal diet + 100 mg/kg FSE). Compared with CON, sows fed FSE showed lower (P &lt; 0.05) wean-to-estrus interval, body weight loss, and higher (P &lt; 0.05) average daily gain of suckling piglet. Sows fed FSE had reduced (P &lt; 0.05) serum malondialdehyde (MDA) content and enhanced (P &lt; 0.05) catalase and glutathione peroxidase (GSH-Px) contents at farrowing and weaning compared with CON. The suckling piglets of FSE-fed sows had increased (P &lt; 0.05) mRNA expressions of nuclear factor erythroid-2 related factor 2, heme oxygenase-1 in the liver, and lower (P &lt; 0.05) serum MDA content on d 0, 7, and 14 of lactation. Sows fed FSE had lower (P &lt; 0.05) serum tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) contents at farrowing and reduced (P &lt; 0.05) serum IL-6 and IL-8 contents at weaning compared with CON. Piglets from FSE-fed sows had enhanced (P ≤ 0.05) villus height and villus height to crypt depth ratio in the jejunum, and higher (P &lt; 0.05) protein expression of Occludin in jejunal mucosa compared with CON. Sows fed FSE tended to have higher (P = 0.09) relative abundance of Lactobacillus at genus level in feces at weaning compared with CON. Our results showed maternal diet supplemented with FSE in lactating sows could effectively induce improvement of performance, antioxidant status, anti-inflammatory function, intestinal morphology, barrier function, and microbial community.

Alterations of the Gut Microbiota in Patients with Diabetic Nephropathy

Diabetic nephropathy (DN) is the primary cause of end-stage renal disease. Accumulating studies have implied a critical role for the gut microbiota in diabetes mellitus (DM) and DN. However, the precise roles and regulatory mechanisms of the gut microbiota in the pathogenesis of DN remain largely unclear. In this study, metagenomics sequencing was performed using fecal samples from healthy controls (CON) and type 2 diabetes mellitus (T2DM) patients with or without DN. Fresh fecal samples from 15 T2DM patients without DN, 15 DN patients, and 15 age-, gender-, and body mass index (BMI)-matched healthy controls were collected. The compositions and potential functions of the gut microbiota were estimated. Although no difference of gut microbiota α and β diversity was observed between the CON, T2DM, and DN groups, the relative abundances of butyrate-producing bacteria (Clostridium, Eubacterium, and Roseburia intestinalis) and potential probiotics (Lachnospira and Intestinibacter) were significantly reduced in T2DM and DN patients. Besides, Bacteroides stercoris was significantly enriched in fecal samples from patients with DN. Moreover, Clostridium sp. 26_22 was negatively associated with serum creatinine (P < 0.05). DN patients could be accurately distinguished from CON by Clostridium sp. CAG_768 (area under the curve [AUC] = 0.941), Bacteroides propionicifaciens (AUC = 0.905), and Clostridium sp. CAG_715 (AUC = 0.908). DN patients could be accurately distinguished from T2DM patients by Pseudomonadales, Fusobacterium varium, and Prevotella sp. MSX73 (AUC = 0.889). Regarding the potential bacterial functions of the gut microbiota, the citrate cycle, base excision repair, histidine metabolism, lipoic acid metabolism, and bile acid biosynthesis were enriched in DN patients, while selenium metabolism and branched-chain amino acid biosynthesis were decreased in DN patients.

IMPORTANCE Gut microbiota imbalance is found in fecal samples from DN patients, in which Roseburia intestinalis is significantly decreased, while Bacteroides stercoris is increased. There is a significant correlation between gut microbiota imbalance and clinical indexes related to lipid metabolism, glucose metabolism, and renal function. The gut microbiota may be predictive factors for the development and progression of DN, although further studies are warranted to illustrate their regulatory mechanisms.

A Polyclonal Aptamer Library for the Specific Binding of the Gut Bacterium Roseburia intestinalis in Mixtures with Other Gut Microbiome Bacteria and Human Stool Samples

Roseburia intestinalis has received attention as a potential probiotic bacterium. Recent studies have demonstrated that changes in its intestinal abundance can cause various diseases, such as obesity, enteritis and atherosclerosis. Probiotic administration or fecal transplantation alter the structure of the intestinal flora, offering possibilities for the prevention and treatment of these diseases. However, current monitoring methods, such as 16S rRNA sequencing, are complex and costly and require specialized personnel to perform the tests, making it difficult to continuously monitor patients during treatment. Hence, the rapid and cost-effective quantification of intestinal bacteria has become an urgent problem to be solved. Aptamers are of emerging interest because their stability, low immunogenicity and ease of modification are attractive properties for a variety of applications. We report a FluCell-SELEX polyclonal aptamer library specific for R. intestinalis isolated after seven evolution rounds, that can bind and label this organism for fluorescence microscopy and binding assays. Moreover, R. intestinalis can be distinguished from other major intestinal bacteria in complex defined mixtures and in human stool samples. We believe that this preliminary evidence opens new avenues towards aptamer-based electronic biosensors as new powerful and inexpensive diagnostic tools for the relative quantitative monitoring of R. intestinalis in gut microbiomes.

Gut microbiome-produced metabolites in pigs: a review on their biological functions and the influence of probiotics

The gastrointestinal tract is a complex ecosystem that contains a large number of microorganisms with different metabolic capacities. Modulation of the gut microbiome can improve the growth and promote health in pigs. Crosstalk between the host, diet, and the gut microbiome can influence the health of the host, potentially through the production of several metabolites with various functions. Short-chain and branched-chain fatty acids, secondary bile acids, polyamines, indoles, and phenolic compounds are metabolites produced by the gut microbiome. The gut microbiome can also produce neurotransmitters (such as γ-aminobutyric acid, catecholamines, and serotonin), their precursors, and vitamins. Several studies in pigs have demonstrated the importance of the gut microbiome and its metabolites in improving growth performance and feed efficiency, alleviating stress, and providing protection from pathogens. The use of probiotics is one of the strategies employed to target the gut microbiome of pigs. Promising results have been published on the use of probiotics in optimizing pig production. This review focuses on the role of gut microbiome-derived metabolites in the performance of pigs and the effects of probiotics on altering the levels of these metabolites.

Liuwei Dihuang Decoction Alleviates Cognitive Dysfunction in Mice With D-Galactose-Induced Aging by Regulating Lipid Metabolism and Oxidative Stress via the Microbiota-Gut-Brain Axis

Background

Aging is an important cause of cognitive dysfunction. Liuwei Dihuang decoction (LW), a commonly applied Chinese medicine formula, is widely used for the treatment of aging-related diseases in China. Previously, LW was confirmed to be effective in prolonging life span and reducing oxidative stress in aged mice. Unfortunately, the underlying mechanism of LW remains unclear. The aim of this study was to interpret the mechanism by which LW alleviates cognitive dysfunction related to aging from the perspective of the microbiota-gut-brain axis.

Method

All C57BL/6 mice (n = 60) were randomly divided into five groups: the control, model, vitamin E (positive control group), low-dose LW and high-dose LW groups (n = 12 in each group). Except for those in the control group, D-galactose was subcutaneously injected into mice in the other groups to induce the aging model. The antiaging effect of LW was evaluated by the water maze test, electron microscopy, 16S rRNA sequencing, combined LC–MS and GC–MS metabolomics, and ELISA.

Results

Liuwei Dihuang decoction ameliorated cognitive dysfunction and hippocampal synaptic ultrastructure damage in aging mice. Moreover, LW decreased Proteobacteria abundance and increased gut microbiota diversity in aging mice. Metabolomic analysis showed that LW treatment was associated with the significantly differential abundance of 14 metabolites, which were mainly enriched in apelin signaling, sphingolipid metabolism, glycerophospholipid and other metabolic pathways. Additionally, LW affected lipid metabolism and oxidative stress in aging mice. Finally, we also found that LW-regulated microbial species such as Proteobacteria and Fibrobacterota had potential relationships with lipid metabolism, oxidative stress and hippocampal metabolites.

Conclusion

In brief, LW improved cognitive function in aging mice by regulating lipid metabolism and oxidative stress through restoration of the homeostasis of the microbiota-gut-brain axis.

Comparison of Intestinal Microbes in Noninfectious Anterior Scleritis Patients With and Without Rheumatoid Arthritis

We compared intestinal microbes in anterior noninfectious scleritis patients with and without rheumatoid arthritis. Active noninfectious anterior scleritis patients without other immune diseases (G group, 16 patients) or with active rheumatoid arthritis (GY group, seven patients) were included in this study. Eight age- and sex-matched healthy subjects served as controls (N group). DNA was extracted from fecal samples. The V3-V4 16S rDNA region was amplified and sequenced by high-throughput 16S rDNA analysis, and microbial contents were determined. A significant decrease in species richness in the GY group was revealed by α- and β-diversity analyses (p = 0.02 and p = 0.004, respectively). At the genus level, 14 enriched and 10 decreased microbes in the G group and 13 enriched and 18 decreased microbes in the GY group were identified. Among them, four microbes were enriched in both the G and GY groups, including Turicibacter, Romboutsia, Atopobium, and Coprobacillus. Although two microbes (Lachnospiraceae_ND3007_group and Eggerthella) exhibited similar tendencies in the G and GY groups, changes in these microbes were more significant in the GY group (p < 0.05). Interaction analysis showed that Intestinibacter, Romboutsia, and Turicibacter, which were enriched in both the G and GY groups, correlated positively with each other. In addition, nine microbes were decreased in the GY group, which demonstrates a potential protective role for these microbes in the pathogenesis of scleritis via interactions with each other.

Gut Microbiota Ecology and Inferred Functions in Children With ASD Compared to Neurotypical Subjects

Autism spectrum disorders (ASDs) is a multifactorial neurodevelopmental disorder. The communication between the gastrointestinal (GI) tract and the central nervous system seems driven by gut microbiota (GM). Herein, we provide GM profiling, considering GI functional symptoms, neurological impairment, and dietary habits. Forty-one and 35 fecal samples collected from ASD and neurotypical children (CTRLs), respectively, (age range, 3–15 years) were analyzed by 16S targeted-metagenomics (the V3–V4 region) and inflammation and permeability markers (i.e., sIgA, zonulin lysozyme), and then correlated with subjects’ metadata. Our ASD cohort was characterized as follows: 30/41 (73%) with GI functional symptoms; 24/41 (58%) picky eaters (PEs), with one or more dietary needs, including 10/41 (24%) with food selectivity (FS); 36/41 (88%) presenting high and medium autism severity symptoms (HMASSs). Among the cohort with GI symptoms, 28/30 (93%) showed HMASSs, 17/30 (57%) were picky eaters and only 8/30 (27%) with food selectivity. The remaining 11/41 (27%) ASDs without GI symptoms that were characterized by HMASS for 8/11 (72%) and 7/11 (63%) were picky eaters. GM ecology was investigated for the overall ASD cohort versus CTRLs; ASDs with GI and without GI, respectively, versus CTRLs; ASD with GI versus ASD without GI; ASDs with HMASS versus low ASSs; PEs versus no-PEs; and FS versus absence of FS. In particular, the GM of ASDs, compared to CTRLs, was characterized by the increase of Proteobacteria, Bacteroidetes, Rikenellaceae, Pasteurellaceae, Klebsiella, Bacteroides, Roseburia, Lactobacillus, Prevotella, Sutterella, Staphylococcus, and Haemophilus. Moreover, Sutterella, Roseburia and Fusobacterium were associated to ASD with GI symptoms compared to CTRLs. Interestingly, ASD with GI symptoms showed higher value of zonulin and lower levels of lysozyme, which were also characterized by differentially expressed predicted functional pathways. Multiple machine learning models classified correctly 80% overall ASDs, compared with CTRLs, based on Bacteroides, Lactobacillus, Prevotella, Staphylococcus, Sutterella, and Haemophilus features. In conclusion, in our patient cohort, regardless of the evaluation of many factors potentially modulating the GM profile, the major phenotypic determinant affecting the GM was represented by GI hallmarks and patients’ age.

Wuwei Qingzhuo San Ameliorates Hyperlipidemia in Mice Fed With HFD by Regulating Metabolomics and Intestinal Flora Composition

Hyperlipidemia is one of the most common metabolic disorders that threaten people’s health. Wuwei Qingzhuo San (WQS) is a traditional Mongolian medicine prescription, which is widely used in Mongolia for the treatment of hyperlipidemia. Our previous studies found that it has hypolipidemic and hepatoprotective effects on hyperlipidemic hamsters. However, the underlying lipid-lowering mechanisms of WQS and its relationship with intestinal flora are not yet clear. In this study, 16 S rRNA gene sequencing and metabolomics were performed to investigate the action mechanism of WQS on hyperlipidemic mice induced by a high-fat diet (HFD). As a result, metabolic pathway enrichment analysis revealed that the intervention of WQS had obviously modulated the metabolism of α-linolenic acid and linoleic acid and the biosynthesis of bile acids. 16 S rRNA sequencing showed that WQS had altered the composition of the intestinal microbiota in hyperlipidemic mice fed with HFD and, especially, adjusted the relative abundance ratio of Firmicutes/Bacteroides. These findings provide new evidence that WQS can improve HFD-induced hyperlipidemia by regulating metabolic disorders and intestinal flora imbalance.

Aging gut microbiota of wild macaques are equally diverse, less stable, but progressively personalized

BACKGROUND

Pronounced heterogeneity of age trajectories has been identified as a hallmark of the gut microbiota in humans and has been explained by marked changes in lifestyle and health condition. Comparatively, age-related personalization of microbiota is understudied in natural systems limiting our comprehension of patterns observed in humans from ecological and evolutionary perspectives.

RESULTS

Here, we tested age-related changes in the diversity, stability, and composition of the gut bacterial community using 16S rRNA gene sequencing with dense repeated sampling over three seasons in a cross-sectional age sample of adult female Assamese macaques (Macaca assamensis) living in their natural forest habitat. Gut bacterial composition exhibited a personal signature which became less stable as individuals aged. This lack of stability was not explained by differences in microbiota diversity but rather linked to an increase in the relative abundance of rare bacterial taxa. The lack of age-related changes in core taxa or convergence with age to a common state of the community hampered predicting gut bacterial composition of aged individuals. On the contrary, we found increasing personalization of the gut bacterial composition with age, indicating that composition in older individuals was increasingly divergent from the rest of the population. Reduced direct transmission of bacteria resulting from decreasing social activity may contribute to, but not be sufficient to explain, increasing personalization with age.

CONCLUSIONS

Together, our results challenge the assumption of a constant microbiota through adult life in a wild primate. Within the limits of this study, the fact that increasing personalization of the aging microbiota is not restricted to humans suggests the underlying process to be evolved instead of provoked only by modern lifestyle of and health care for the elderly. Video abstract.

How Diet and Physical Activity Modulate Gut Microbiota: Evidence, and Perspectives

Gut microbiota plays a significant role in the maintenance of physiological homeostasis, contributing to human health. Nevertheless, some factors (sex, age, lifestyle, physical activity, drug-based therapies, diet, etc.) affect its composition and functionality, linked to pathologies and immunological diseases. Concerning diet, it interacts with microorganisms, leading to beneficial or detrimental outcomes for the health of host. On the other hand, physical activity is known to be useful for preventing and, sometimes, treating several diseases of cardiovascular, neuroendocrine, respiratory, and muscular systems. This paper focuses on diet and physical activity presenting the current knowledge about how different diets (Western, ketogenic, vegan, gluten free, Mediterranean) as well as different types of exercise (intensive, endurance, aerobic) could shape gut microbiota.

Characteristics and Mediating Effect of Gut Microbiota With Experience of Childhood Maltreatment in Major Depressive Disorder

Gut microbiota and childhood maltreatment are closely related to depressive symptoms. This study aimed to analyze the characteristics of gut microbiota in major depressive disorder (MDD) patients with childhood maltreatment experience and explore the correlation between gut microbiota, childhood maltreatment, and depressive symptoms. A total of 37 healthy controls (HCs) and 53 patients with MDD were enrolled, including 18 MDD patients without childhood maltreatment experience and 35 MDD patients with childhood maltreatment experience. The Hamilton’s Depression Scale (HAMD-24) and Childhood Trauma Questionnaire-Short Form (CTQ-SF) were used to evaluate their depressive symptoms and childhood maltreatment experience, respectively. The composition of gut microbiota was evaluated using 16S rRNA sequencing. Spearman’s correlation analysis was used to evaluate the correlation between different gut microbiota, depressive symptoms and childhood maltreatment. The mediation analysis was used to evaluate the mediating effect of gut microbiota. In the α-diversity analysis, we found that the Simpson index and Pielou’s Evenness index differed significantly between MDD patients without childhood maltreatment experience and HCs. In the β-diversity analysis, principal coordinate analysis (PCoA) showed significant differences between MDD patients without childhood maltreatment experience, MDD patients with childhood maltreatment experience and HCs. Twenty-seven different bacteria were identified through Linear discriminant analysis effect size (LEfSe) analysis at different levels of classification. The analysis of the correlation showed that Blautia, Bifidobacterium, Bacteroides, Roseburia, and Phascolarctobacterium were significantly correlated with HAMD and CTQ-SF scores. The mediation analysis showed that childhood maltreatment had a significant direct effect on the patients’ depressive symptoms, and Blautia, Bifidobacterium, Roseburia had a significant mediating effect. The findings of this study suggested that MDD patients with childhood maltreatment experience had different gut microbiota, which might have a mediating effect on the influence of childhood maltreatment on depressive symptoms.

Red Raspberry and Fructo-Oligosaccharide Supplementation, Metabolic Biomarkers, and the Gut Microbiota in Adults with Prediabetes: A Randomized Crossover Clinical Trial

BACKGROUND

Evidence suggests that the gut microbiota and cardiometabolic status are associated, suggesting dietary interventions that alter the microbiota may affect metabolic health.

OBJECTIVES

We investigated whether supplementation with (poly)phenol-dense red raspberries (RRB), alone or with a fructo-oligosaccharide (FOS) prebiotic, would improve biomarkers of cardiometabolic risk in individuals with prediabetes (PreDM) and insulin resistance (IR) and whether the effects are related to modulation of the gut microbiota.

METHODS

Adults with PreDM-IR (n = 26; mean ± SEM age, 35 ± 2 years; fasting glucose, 5.7 ± 0.1 mmol/L; HOMA-IR, 3.3 ± 0.3) or who were metabolically healthy (reference group; n = 10; age, 31 ± 3 years; fasting glucose, 5.1 ± 0.2 mmol/L; HOMA-IR, 1.1 ± 0.1) participated in a randomized crossover trial with two 4-week supplementation periods, in which they consumed either RRB (125 g fresh equivalents) daily or RRB + 8g FOS daily, separated by a 4-week washout. The primary outcome variable was the change in the gut microbiota composition, assessed by shotgun sequencing before (baseline) and at the end of each supplementation period. Secondary outcomes were changes in glucoregulation, lipid metabolism, anti-inflammatory status, and anthropometry. The trial is registered at ClinicalTrials.gov, NCT03049631.

RESULTS

In PreDM-IR, RRB supplementation reduced hepatic-IR (-30.1% ± 14.6%; P = 0.04) and reduced plasma total and LDL cholesterol [-4.9% ± 1.8% (P = 0.04) and -7.2% ± 2.3% (P = 0.003), respectively] from baseline. Adding FOS (RRB + FOS) improved β-cell function [insulin secretion rate, +70.2% ± 32.8% (P = 0.02); Disposition Index, +94.4% ± 50.2% (P = 0.04)], but had no significant effect on plasma cholesterol compared to baseline. RRB increased Eubacterium eligens (2-fold) and decreased Ruminococcus gnavus (-60% ± 34%), whereas RRB + FOS increased Bifidobacterium spp. (4-fold) and decreased Blautia wexlerae (-23% ± 12%) from baseline (all P values ≤ 0.05). R. gnavus was positively correlated with hepatic-IR, and E. eligens and Bifidobacterium catenulatum were negatively correlated with cholesterol concentrations (P ≤ 0.05).

CONCLUSIONS

Increased Bifidobacterium spp., concurrently with reduced R. gnavus, was associated with metabolic improvements in adults with PreDM-IR, warranting further research on the mechanisms involved in (poly)phenol/FOS-microbial interactions with host metabolism.

Precision environmental health monitoring by longitudinal exposome and multi-omics profiling

Conventional environmental health studies have primarily focused on limited environmental stressors at the population level, which lacks the power to dissect the complexity and heterogeneity of individualized environmental exposures. Here, as a pilot case study, we integrated deep-profiled longitudinal personal exposome and internal multi-omics to systematically investigate how the exposome shapes a single individual's phenome. We annotated thousands of chemical and biological components in the personal exposome cloud and found they were significantly correlated with thousands of internal biomolecules, which was further cross-validated using corresponding clinical data. Our results showed that agrochemicals and fungi predominated in the highly diverse and dynamic personal exposome, and the biomolecules and pathways related to the individual's immune system, kidney, and liver were highly associated with the personal external exposome. Overall, this data-driven longitudinal monitoring study shows the potential dynamic interactions between the personal exposome and internal multi-omics, as well as the impact of the exposome on precision health by producing abundant testable hypotheses.

The influence of perceived stress on the human microbiome

Objective

Microbial dysbiosis, a shift from commensal to pathogenic microbiota, is often associated with mental health and the gut–brain axis, where dysbiosis in the gut may be linked to dysfunction in the brain. Many studies focus on dysbiosis induced by clinical events or traumatic incidents; however, many professions in austere or demanding environments may encounter continuously compounded stressors. This study seeks to explore the relationship between microbial populations and stress, both perceived and biochemical.

Results

Eight individuals enrolled in the study to provide a longitudinal assessment of the impact of stress on gut health, with four individuals providing enough samples for analysis. Eleven core microbial genera were identified, although the relative abundance of these genera and other members of the microbial population shifted over time. Although our results indicate a potential relationship between perceived stress and microbial composition of the gut, no association with biochemical stress was observed. Increases in perceived stress seem to elucidate a change in potentially beneficial Bacteroides, with a loss in Firmicutes phyla. This shift occurred in multiple individuals, whereas using cortisol as a stress biomarker showed contradictory responses. These preliminary data provide a potential mechanism for gut monitoring, while identifying targets for downstream modulation.

Characterization of intestinal microbiota in normal weight and overweight Border Collie and Labrador Retriever dogs

Obesity in dogs is an emerging issue that affects canine health and well-being. Its development is ascribed to several factors, including genetic predisposition and dietary management, and recent evidence suggests that intestinal microbiota may be involved as well. Previous works have shown obesity to be linked to significant changes in gut microbiota composition in humans and mice, but only limited information is available on the role played by canine gut microbiota. The aim of this exploratory study was to investigate whether composition of canine faecal microbiota may be influenced by overweight condition and breed. All the enrolled companion dogs were young adults, intact, healthy, and fed commercial extruded pet food; none had received antibiotics, probiotics or immunosuppressant drugs in the previous six months. Labrador Retriever (LR) and Border Collie (BC) were chosen as reference breeds and Body Condition Score (BCS) on a 9-point scale as reference method for evaluating body fat. The faecal microbial communities of 15 lean (BCS 4-5/9; 7 LRs and 8 BCs) and 14 overweight (BCS > 5/9; 8 LRs and 6 BCs) family dogs were analysed using 16S rRNA gene sequencing. Moreover, for each dog, the daily intake of energy (kcal/d) and dietary macronutrients (g/d) were calculated according to an accurate feeding history collection. Firmicutes and Bacteroidetes resulted the predominant phyla (51.5 ± 10.0% and 33.4 ± 8.5%, respectively) in all dogs. Bioinformatic and statistical analysis revealed that no bacterial taxon differed significantly based on body condition, except for genus Allisonella (p < 0.05); BC gut microbiota was richer (p < 0.05) in bacteria belonging to phyla Actinobacteria (family Coriobacteriaceae in particular) and Firmicutes (Allobaculum and Roseburia genera). No remarkable differences were recorded either for diversity indices (i.e., alpha diversity, p > 0.10) or for divergence within the sample set (i.e., beta diversity, p > 0.05). PERMANOVA tests performed on single factors demonstrated the tendency of dietary protein to influence the recruited dogs' microbiota beta-diversity at amplicon sequence variant level (p = 0.08). In conclusion, the faecal microbiota of dogs involved in this exploratory study showed no major variations based on body condition. However, our findings suggested that certain bacterial taxa previously acknowledged in obesity-related studies may be detected in dissimilar amounts depending on canine breed.

Exercise and Prebiotic Fiber Provide Gut Microbiota-Driven Benefit in a Survivor to Germ-Free Mouse Translational Model of Breast Cancer

Simple Summary

Breast cancer is the most common cancer in women worldwide. In recent years, the community of microbes that inhabit the intestinal tract, called the gut microbiota, has been shown to influence patient response to several cancer therapies. On the other hand, treatments such as chemotherapy can disrupt the resident gut microbiota and potentially contribute to poor health outcomes. Strategies to improve the composition of the gut microbiota include dietary and exercise interventions. While diet and exercise are already established as important for breast cancer prevention, during treatment, and for reducing recurrence, little is known about the impact of these factors on the gut microbiota in the context of breast cancer. Therefore, our aim was to examine the impact of exercise and diet on the gut microbiota in breast cancer. Our findings indicate that exercise and prebiotic fiber supplementation may provide benefits to individuals with breast cancer through advantageous gut microbial changes. Our findings of a potential adjuvant of exercise and prebiotics should inspire further mechanistic and clinical investigations.

Abstract

The gut microbiota plays a role in shaping overall host health and response to several cancer treatments. Factors, such as diet, exercise, and chemotherapy, can alter the gut microbiota. In the present study, the Alberta Cancer Exercise (ACE) program was investigated as a strategy to favorably modify the gut microbiota of breast cancer survivors who had received chemotherapy. Subsequently, the ability of post-exercise gut microbiota, alone or with prebiotic fiber supplementation, to influence breast cancer outcomes was interrogated using fecal microbiota transplant (FMT) in germ-free mice. While cancer survivors experienced little gut microbial change following ACE, in the mice, tumor volume trended consistently lower over time in mice colonized with post-exercise compared to pre-exercise microbiota with significant differences on days 16 and 22. Beta diversity analysis revealed that EO771 breast tumor cell injection and Paclitaxel chemotherapy altered the gut microbial communities in mice. Enrichment of potentially protective microbes was found in post-exercise microbiota groups. Tumors of mice colonized with post-exercise microbiota exhibited more favorable cytokine profiles, including decreased vascular endothelial growth factor (VEGF) levels. Beneficial microbial and molecular outcomes were augmented with prebiotic supplementation. Exercise and prebiotic fiber demonstrated adjuvant action, potentially via an enhanced anti-tumor immune response modulated by advantageous gut microbial shifts.

Intestinal Flora Mediates Antiobesity Effect of Rutin in High-Fat-Diet Mice

SCOPE

Intestinal flora plays a critical role in the development of . Rutin is a natural flavonoid with potential prebiotic effects on regulating the intestinal flora composition that is beneficial for host health. Therefore, this study hypothesizes that rutin supplementation has beneficial effects on high-fat-diet (HFD)-induced obesity and metabolic disorder through the modulation of intestinal flora in mice.

METHODS AND RESULTS

The obesity-alleviating property of rutin using 6-week-old C57BL/6J male mice fed on HFD with or without rutin supplementation for 16 weeks is investigated. Rutin supplementation effectively reduces body-weight gain, insulin resistance, and acted favorably on the intestinal barrier, thereby reducing endotoxemia and systemic inflammation. Sequencing of 16S rRNA genes from fecal samples indicate that rutin exerted modulatory effects on HFD-induced intestinal flora disorders (e.g., rutin decreased Firmicutes abundance and increased Bacteroidetes and Verrucomicrobia abundance). Antibiotic treatment and fecal microbiota transplantation further demonstrate that the salutary effects of rutin on obesity control are strongly dependent on the intestinal flora.

CONCLUSION

Rutin can be considered as a prebiotic agent for improving intestinal flora disorders and obesity-associated metabolic perturbations in obese individuals.

Integrative multiomics analysis reveals host-microbe-metabolite interplays associated with the aging process in Singaporeans

The age-associated alterations in microbiomes vary across populations due to the influence of genetics and lifestyles. To the best of our knowledge, the microbial changes associated with aging have not yet been investigated in Singapore adults. We conducted shotgun metagenomic sequencing of fecal and saliva samples, as well as fecal metabolomics to characterize the gut and oral microbial communities of 62 healthy adult male Singaporeans, including 32 young subjects (age, 23.1 ± 1.4 years) and 30 elderly subjects (age, 69.0 ± 3.5 years). We identified 8 gut and 13 oral species that were differentially abundant in elderly compared to young subjects. By combining the gut and oral microbiomes, 25 age-associated oral-gut species connections were identified. Moreover, oral bacteria Acidaminococcus intestine and Flavonifractor plautii were less prevalent/abundant in elderly gut samples than in young gut samples, whereas Collinsella aerofaciens and Roseburia hominis showed the opposite trends. These results indicate the varied gut-oral communications with aging. Subsequently, we expanded the association studies on microbiome, metabolome and host phenotypic parameters. In particular, Eubacterium eligens increased in elderly compared to young subjects, and was positively correlated with triglycerides, which implies that the potential role of E. eligens in lipid metabolism is altered during the aging process. Our results demonstrated aging-associated changes in the gut and oral microbiomes, as well as the connections between metabolites and host-microbe interactions, thereby deepening the understanding of alterations in the human microbiome during the aging process in a Singapore population.

The Probiotic Lactobacillus paracasei Ameliorates Diarrhea Cause by Escherichia coli O8via Gut Microbiota Modulation1

Introduction

Koumiss is a fermented horse milk food containing abundant probiotics. Lactobacillus paracasei is a bacterial strain isolated from koumiss that helps regulate the intestinal microbiota. One of the major cause of diarrhea is an imbalance of the intestinal flora. The aim of this study was to investigate whether Lactobacillus paracasei can ameliorate E. coli-induced diarrhea and modulate the gut microbiota.

Methods

Mouse models of diarrhea were established via intragastric E. coli O₈ administration. We then attempted to prevent or treat diarrhea in the mice via intragastric administration of a 3 × 10⁸ CFU/mL L. paracasei cell suspension. The severity of diarrhea was evaluated based on the body weight, diarrhea rate, and index, fecal diameter, ileum injury, hematoxylin-eosin (H&E) staining, and diamine oxidase (DAO) and zonulin expression. Expression of the tight junction (TJ) proteins claudin-1, occludin, and zona occludens (ZO-)1 were detected by immunohistochemistry (IHC). Gastrointestinal mRNA expression levels of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α were detected by real-time polymerase chain reaction (RT-PCR). The microbial composition was analyzed by 16s rRNA sequencing.

Results

The L. paracasei demonstrated excellent therapeutic efficacy against diarrhea. It elevated the TJ protein levels and downregulated proinflammatory cytokines IL-6, IL-1β, TNF-α, and p65, myosin light chain 2 (MLC2), myosin light chain kinase (MLCK). Moreover L. paracasei increased those bacteria, which can product short-chain fatty acid (SCFA) such Alistipes, Odoribacter, Roseburia, and Oscillibacter.

Conclusion

L. paracasei ameliorated diarrhea by inhibiting activation of the nuclear factor kappa B (NF-κB)-MLCK pathway and increasing the abundance of gut microbiota that produce SCFA.

A preliminary study on the diversity of butyrate-producing bacteria in response to the treatment of depression with Xiaoyaosan

Butyrate-producing bacteria generate butyrate, which has antidepressant effects. Xiaoyaosan (XYS), a traditional Chinese medicine (TCM) used to treat depression, may improve depression-like behaviour by modulating the gut microbiota. However, the functional groups and mechanisms of action in the XYS treatment of depression remain unknown. This study aimed to analyse with clone sequencing the changes in intestinal butyrate-producing bacteria in XYS-treated chronic unpredictable mild stress (CUMS) rats. We successfully established the XYS-treated CUMS rat model of depression. Rat faecal samples were collected before, during, and after the experiment, and butyryl-CoA:acetate CoA-transferase gene primers were selected for PCR amplification to determine the diversity of butyrate-producing bacteria. The results showed that XYS increased intestinal butyrate-producing bacterial diversity in CUMS rats regarding phylum and genus numbers; the number of phyla increased to two, distributed in Firmicutes and Bacteroides, and four genera were distributed in Eubacterium sp., Roseburia sp., Clostridium sp. and Bacteroides sp. Only one phylum and two genera were present in the model group without XYS treatment. Our findings indicate that XYS can improve depression-like behaviour by regulating intestinal butyrate-producing bacteria diversity, particularly Roseburia sp. and Eubacterium sp., thus providing new insights into the targeted regulation of the intestinal flora to treat depression.

Prebiotic Potential of Dietary Beans and Pulses and Their Resistant Starch for Aging-Associated Gut and Metabolic Health

Dietary pulses, including dry beans, lentils, chickpeas, and dry peas, have the highest proportion of fiber among different legume cultivars and are inexpensive, easily accessible, and have a long shelf-life. The inclusion of pulses in regular dietary patterns is an easy and effective solution for achieving recommended fiber intake and maintaining a healthier gut and overall health. Dietary pulses-derived resistant starch (RS) is a relatively less explored prebiotic ingredient. Several in vitro and preclinical studies have elucidated the crucial role of RS in fostering and shaping the gut microbiota composition towards homeostasis thereby improving host metabolic health. However, in humans and aged animal models, the effect of only the cereals and tubers derived RS has been studied. In this context, this review collates literature pertaining to the beneficial effects of dietary pulses and their RS on gut microbiome-metabolome signatures in preclinical and clinical studies while contemplating their potential and prospects for better aging-associated gut health. In a nutshell, the incorporation of dietary pulses and their RS in diet fosters the growth of beneficial gut bacteria and significantly enhances the production of short-chain fatty acids in the colon.

Effect of 6-Methoxybenzoxazolinone on the Cecal Microbiota of Adult Male Brandt's Vole

The anti-microbial effects of plant secondary metabolite (PSM) 6-methoxybenzoxazolinone (6-MBOA) have been overlooked. This study investigated the effect of 6-MBOA on the cecal microbiota of adult male Brandt’s voles (Lasiopodomys brandtii), to evaluate its effect on the physiology of mammalian herbivores. The growth of voles was inhibited by 6-MBOA. A low dose of 6-MBOA enhanced the observed species, as well as the Chao1 and abundance-based coverage estimator (ACE) indices and introduced changes in the structure of cecal microbiota. The abundance of the phylum Tenericutes, classes Mollicutes and Negativicutes, order Selenomonadales, families Ruminococcaceae and Veillonellaceae, genera Quinella, Caproiciproducens, Anaerofilum, Harryflintia, and unidentified Spirochaetaceae in the cecal microbiota was enhanced upon administration of a low dose of 6-MBOA, which also inhibited glucose metabolism and protein digestion and absorption in the cecal microbiota. 6-MBOA treatment also stimulated butyrate production and dose-dependently enhanced the metabolism of xenobiotics in the cecal microbiome. Our findings indicate that 6-MBOA can affect Brandt’s voles by inducing changes in the abundance of cecal bacteria, thereby, altering the contents of short-chain fatty acids (SCFAs) and pathway intermediates, ultimately inhibiting the growth of voles. Our research suggests that 6-MBOA could potentially act as a digestion-inhibiting PSM in the interaction between mammalian herbivores and plants.

Gut microbiome responses to dietary intervention with hypocholesterolemic vegetable oils

Hypercholesterolemia is becoming a problem with increasing significance. Dietary vegetable oils may help to improve this condition due to presence of phytonutrients with potentially synergistic cholesterol-lowering effects. The objective of this 8-week double-blinded randomized clinical trial was to investigate the effects of consuming 30 g of two different blended cooking oils, rich in omega-3 alpha-linolenic acid and phytonutrients, or refined olive oil on the intestinal microbiota in 126 volunteers with borderline hypercholesterolemia. Multi-factor analysis of relationships between the gut microbiota composition at various taxonomic ranks and the clinical trial parameters revealed the association between beneficial effects of the dietary intervention on the blood lipid profile with abundance of Clostridia class of the gut microbiota. This microbiota feature was upregulated in the course of the dietary intervention and associated with various plasma markers of metabolic health status, such as Triglycerides, Apolipoprotein B and Total Cholesterol to HDL ratio in a beneficial way. The relative abundance of a single species—Clostridium leptum—highly increased during the dietary intervention in all the three study groups. The oil blend with the highest concentration of omega-3 PUFA is associated with faster and more robust responses of the intestinal microbiota, including elevation of alpha-diversity. Butyrate production is being discussed as a plausible process mediating the observed beneficial influence on the plasma lipid profile. Causal mediation analysis suggested that Clostridium genus rather than the higher rank of the phylogeny—Clostridia class—may be involved in the diet-induced improvements of the blood lipid profile.