Colonic Microbiota Research Articles

Effects of Hibernation on Colonic Epithelial Tissue and Gut Microbiota in Wild Chipmunks (Tamias sibiricus)

The gut microbiota plays a crucial role in the host’s metabolic processes. Many studies have shown significant changes in the gut microbiota of mammals during hibernation to adapt to the changes in the external environment, but there is limited research on the colonic epithelial tissue and gut microbiota of the wild chipmunks during hibernation. This study analyzed the diversity, composition, and function of the gut microbiota of the wild chipmunk during hibernation using 16S rRNA gene high-throughput sequencing technology, and further conducted histological analysis of the colon. Histological analysis of the colon showed an increase in goblet cells in the hibernation group, which was an adaptive change to long-term fasting during hibernation. The dominant gut microbial phyla were Bacteroidetes, Firmicutes, and Proteobacteria, and the relative abundance of them changed significantly. The analysis of gut microbiota structural differences indicated that the relative abundance of Helicobacter typhlonius and Mucispirillum schaedleri increased significantly, while unclassified Prevotella-9, unclassified Prevotellaceae-UCG-001, unclassified Prevotellaceae-UCG-003 and other species of Prevotella decreased significantly at the species level. Alpha diversity analysis showed that hibernation increased the diversity and richness of the gut microbiota. Beta diversity analysis revealed significant differences in gut microbiota diversity between the hibernation group and the control group. PICRUSt2 functional prediction analysis of the gut microbiota showed that 15 pathways, such as lipid metabolism, xenobiotics biodegradation and metabolism, amino acid metabolism, environmental adaptation, and neurodegenerative diseases, were significantly enriched in the hibernation group, while 12 pathways, including carbohydrate metabolism, replication and repair, translation, and transcription, were significantly enriched in the control group. It can be seen that during hibernation, the gut microbiota of the wild chipmunk changes towards taxa that are beneficial for reducing carbohydrate consumption, increasing fat consumption, and adapting more strongly to environmental changes in order to better provide energy for the body and ensure normal life activities during hibernation.

Oral microbiota transplantation for intra-oral halitosis: a feasibility analysis based on an oral microbiota colonization trial in Wistar rats

BackgroundIntra-oral halitosis (IOH) is bad breath produced locally by the mouth in addition to systemic diseases and is one of the main causes of interpersonal communication and psychological disorders in modern society. However, current treatment modalities still only alleviate IOH and do not eradicate it. Therefore, based on the differential performance of oral microecology in IOH patients, we propose a microbiota transplantation treatment aimed at restoring oral microecological balance and analyze its feasibility by oral flora colonization test in Wistar rats.ObjectiveSaliva flora samples were collected from IOH patients and healthy subjects to analyze the feasibility of oral microbiota transplantation (OMT) for the treatment of IOH by the Wistar rat oral flora colonization test.MethodsSeven patients with IOH who visited the First Affiliated Hospital of Xinjiang Medical University from June 2017 to June 2022 with the main complaint of halitosis and three healthy subjects were randomly selected. A Halimeter portable breath detector was used to record breath values and collect saliva flora samples. Sixteen SPF-grade male Wistar rats were housed in the Animal Experiment Center of Xinjiang Medical University and randomly divided into an experimental group (Group E) and a control group (Group C) for the oral flora colonization test. Species composition and associated metabolic analysis of oral flora during the Wistar rat test using 16SrRNA sequencing technology and PICRUSt metabolic analysis. Also, the changes in the breath values of the rats were recorded during the test.ResultsThe proportion of Porphyromonas, Fusobacterium, Leptotrichia, and Peptostreptococcus was significantly higher in group E compared to group C after colonization of salivary flora of IOH patients (all P < 0.05), and the abundance with Gemella was zero before colonization, while no colonization was seen in group C after colonization compared to baseline. PICRUSt metabolic analysis also showed significantly enhanced IOH-related metabolic pathways after colonization in group E (all P < 0.05), as well as significantly higher breath values compared to baseline and group C (all P < 0.0001). After colonization by salivary flora from healthy subjects, group E rats showed a decrease in the abundance of associated odor-causing bacteria colonization, a reduction in associated metabolism, and a significant decrease in breath values. In contrast, group C also showed differential changes in flora structure and breath values compared to baseline after salivary flora colonization of IOH patients.ConclusionsOMT for IOH is a promising green treatment option, but the influence of environmental factors and individual differences still cannot be ignored.

Early-life factors shaping the gut microbiota of Common buzzard nestlings

BackgroundExploring the dynamics of gut microbiome colonisation during early-life stages is important for understanding the potential impact of microbes on host development and fitness. Evidence from model organisms suggests a crucial early-life phase when shifts in gut microbiota can lead to immune dysregulation and reduced host condition. However, our understanding of gut microbiota colonisation in long-lived vertebrates, especially during early development, remains limited. We therefore used a wild population of common buzzard nestlings (Buteo buteo) to investigate connections between the early-life gut microbiota colonisation, environmental and host factors.ResultsWe targeted both bacterial and eukaryotic microbiota using the 16S and 28S rRNA genes. We sampled the individuals during early developmental stages in a longitudinal design. Our data revealed that age significantly affected microbial diversity and composition. Nest environment was a notable predictor of microbiota composition, with particularly eukaryotic communities differing between habitats occupied by the hosts. Nestling condition and infection with the blood parasite Leucocytozoon predicted microbial community composition.ConclusionOur findings emphasise the importance of studying microbiome dynamics to capture changes occurring during ontogeny. They highlight the role of microbial communities in reflecting host health and the importance of the nest environment for the developing nestling microbiome. Overall, this study contributes to understanding the complex interplay between microbial communities, host factors, and environmental variables, and sheds light on the ecological processes governing gut microbial colonisation during early-life stages.

A Comparison of Currently Available and Investigational Fecal Microbiota Transplant Products for Recurrent Clostridioides difficile Infection.

Clostridioides difficile infection (CDI) is an intestinal infection that causes morbidity and mortality and places significant burden and cost on the healthcare system, especially in recurrent cases. Antibiotic overuse is well recognized as the leading cause of CDI in high-risk patients, and studies have demonstrated that even short-term antibiotic exposure can cause a large and persistent disturbance to human colonic microbiota. The recovery and sustainability of the gut microbiome after dysbiosis have been associated with fewer CDI recurrences. Fecal microbiota transplantation (FMT) refers to the procedure in which human donor stool is processed and transplanted to a patient with CDI. It has been historically used in patients with pseudomembranous colitis even before the discovery of Clostridioides difficile. More recent research supports the use of FMT as part of the standard therapy of recurrent CDI. This article will be an in-depth review of five microbiome therapeutic products that are either under investigation or currently commercially available: Rebyota (fecal microbiota, live-jslm, formerly RBX2660), Vowst (fecal microbiota spores, live-brpk, formerly SER109), VE303, CP101, and RBX7455. Included in this review is a comparison of the products' composition and dosage forms, available safety and efficacy data, and investigational status.

Preservation of conjugated primary bile acids by oxygenation of the small intestinal microbiota in vitro.

Conjugated primary bile acids are produced by the liver and exist at high concentrations in the proximal small intestine, where they are critical for proper digestion. Deconjugation of these bile acids with subsequent transformation via dehydroxylation into secondary bile acids is regulated by the colonic gut microbiota and reduces their digestive function. Using an in vitro platform modeling the small intestinal microbiota, we analyzed the ability of this community to transform primary bile acids and studied the effect of physiological levels of oxygen normally found in the proximal small intestine (5%) on this metabolic process. We found that oxygenation of the small intestinal microbiota inhibited the deconjugation of primary bile acids in vitro. These findings suggest that luminal oxygen levels normally found in the small intestine may maintain the optimal role of bile acids in the digestive process by regulating bile acid conversion by the gut microbiota.

Diet influences community dynamics following vaginal group B streptococcus colonization.

The vaginal microbiota plays a pivotal role in reproductive, sexual, and perinatal health and disease. Unlike the well-established connections between diet, metabolism, and the intestinal microbiota, parallel mechanisms influencing the vaginal microbiota and pathogen colonization remain overlooked. In this study, we combine a mouse model of Streptococcus agalactiae strain COH1 [group B Streptococcus (GBS)] vaginal colonization with a mouse model of pubertal-onset obesity to assess diet as a determinant of vaginal microbiota composition and its role in colonization resistance. We leveraged culture-dependent assessment of GBS clearance and culture-independent, sequencing-based reconstruction of the vaginal microbiota in relation to diet, obesity, glucose tolerance, and microbial dynamics across time scales. Our findings demonstrate that excessive body weight gain and glucose intolerance are not associated with vaginal GBS density or timing of clearance. Diets high in fat and low in soluble fiber are associated with vaginal GBS persistence, and changes in vaginal microbiota structure and composition due to diet contribute to GBS clearance patterns in nonpregnant mice. These findings underscore a critical need for studies on diet as a key determinant of vaginal microbiota composition and its relevance to reproductive and perinatal outcomes.IMPORTANCEThis work sheds light on diet as a key determinant influencing the composition of vaginal microbiota and its involvement in group B Streptococcus (GBS) colonization in a mouse model. This study shows that mice fed diets with different nutritional composition display differences in GBS density and timing of clearance in the female reproductive tract. These findings are particularly significant given clear links between GBS and adverse reproductive and neonatal outcomes, advancing our understanding by identifying critical connections between dietary components, factors originating from the intestinal tract, vaginal microbiota, and reproductive outcomes.

Antibiotic-induced microbiome depletion promotes intestinal colonization by Campylobacter jejuni in mice

BackgroundTo establish a method to induce Campylobacter jejuni colonization in the intestines of C57BL/6 mice through antibiotic-induced microbiome depletion.ResultsFifty-four female C57BL/6 mice were divided into the normal, control, and experimental groups. The experimental group was administered intragastric cefoperazone sodium and sulbactam sodium (50 mg/mL) for 2 days; then, the experimental and control mice were intragastrically administered 200 µL C. jejuni, which was repeated once more after 2 days. Animal feces were collected, and the HipO gene of C. jejuni was detected using TaqMan qPCR from day 1 to day 14 after modeling completion. Immunofluorescence was used to detect intestinal C. jejuni colonization on day 14, and pathological changes were observed using hematoxylin and eosin staining. Additionally, 16S rDNA analyses of the intestinal contents were conducted on day 14. In the experimental group, C. jejuni was detected in the feces from days 1 to 14 on TaqMan qPCR, and immunofluorescence-labeled C. jejuni were visibly discernable in the intestinal lumen. The intestinal mucosa was generally intact and showed no significant inflammatory-cell infiltration. Diversity analysis of the colonic microbiota showed significant inter-group differences. In the experimental group, the composition of the colonic microbiota differed from that in the other 2 groups at the phylum level, and was characterized by a higher proportion of Bacteroidetes and a lower proportion of Firmicutes.ConclusionsMicrobiome depletion induced by cefoperazone sodium and sulbactam sodium could promote long-term colonization of C. jejuni in the intestines of mice.

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

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

69 Effect evaluation of two sources of zinc at EU-authorized level on growth performance and gut health of piglets with a low or normal birth weight

Abstract This study aimed to investigate the effect of ZnSO4 or a porous form of ZnO, at EU-authorized level, on growth performance, gut health and colon microbiota in low and normal birth body weight (BBW) piglets. At birth, 64 piglets were chosen by their BBW and divided into low BBW (LBBW &amp;lt; 1 kg; 32 piglets) and normal BBW (NBBW &amp;gt; 1 kg; 32 piglets). At weaning, 25 d old (d 0), piglets were allocated into four groups (8 piglets/group, 2 pigs/replicate) and fed a standard diet plus 120 ppm of Zn from ZnSO4 or from a porous source of Zn (HZ - HiZox, Animine, France). Groups were balanced for litter of origin and category of BBW. Piglets were weighed weekly until d 21 post-weaning. The prevalence of diarrhea was determined by the fecal index (percentage of animals with fecal score &amp;gt; 3), and feed intake per pen was recorded daily. On d 9 and d 21, one piglet/replicate was slaughtered, and jejunum tissue was collected for morphology, colon content for microbiota analyzes, and distal jejunum pH was measured. Performance, pH, and morphometric parameters were analyzed using a linear mixed model, fecal index using a generalized linear mixed model with a Poisson distribution, including treatment, class of BBW and their interaction as fixed factors, and the litter as random factor. The statistical analysis on alpha, beta diversity and taxonomic composition were carried out using phyloseq, vegan and microbiomeMarker packages. Piglets in the NBBW group had greater BW throughout the study (P &amp;lt; 0.01). The treatment HZ tended to increase the average daily gain (ADG) at d 9-14 (P &amp;lt; 0.10), and significantly increased the gain to feed ratio (G:F) ratio (P &amp;lt; 0.05) at d 0-14. The HZ-fed piglets had a greater G:F in the overall period (P = 0.04). Additionally, the jejunum pH of the HZ-fed piglets was reduced (P = 0.02) at d 21. An interaction was observed between treatment and BBW for fecal index during d 0-14 and d 0-21 (P &amp;lt; 0.01), in which HZ decreased the index in LBBW. An interaction was also observed in villus height (P = 0.05) and absorptive mucosal surface (P = 0.02) on d 21, that resulted greater in NBBW piglets fed ZnSO4. For Beta diversity, using the Adonis test, BBW category tended to affect the microbial structure at d 9 (R2 = 0.04; P = 0.07) and significantly affected the bacterial structure (R2 = 0.05, P = 0.03) at d 21. At d 21, the NBBW piglets fed ZnSO4 had a greater abundance of Succinivibrio which is able to degrade complex carbohydrates, while the NBBW piglets fed HZ had a greater abundance of Ruminococcus gauvreauii which is linked to the production of short chain fatty acids (SCFAs). The use of HZ seems can be a part of the strategy to replace the pharmacological level of ZnO.

180 Dietary milk fat globule membrane alters intestinal microbiota of neonatal piglet following lipopolysaccharide challenge and marker of neuroinflammation

Abstract Early life stress exposure can increase morbidity and reduce animal wellbeing throughout life. Dysregulated gut function has been associated with neurological changes, and neurological changes affect gut homeostasis. Maternal milk is the gold-standard for yielding developmental benefits to offspring. Identification of milk components has led to an understanding of the bioactive nutrients important in neonatal development. Components of the milk fat globule membrane (MFGM) contribute immensely to neonatal gut health and neurodevelopment. However, mechanisms of actions are still being defined. The objective is to understand how dietary MFGM modulates the gut microbiota, blood-brain barrier tight junctions, and brain inflammatory markers following lipopolysaccharide (LPS) challenge. Piglets (n = 24, one-d-old) were assigned to soy (CON) or MFGM phospholipid supplemented diet (0.75% wt/wt) ± LPS (100 µg/kg body weight) in a 2 × 2 factorial design (n = 6 animals•diet-1•challenge-1.). Piglets were fed for 21 d and 6 animals/diet received saline or LPS injections 4 h before euthanasia. Colonic microbiota was characterized through 16s rRNA gene sequencing, while hypothalamus samples were collected to evaluate brain barrier function and inflammation-related genes using RT-qPCR. Microbiota data were processed using QIIME2 with DADA2 plugin and analyzed for alpha-diversity, beta-diversity, and differential abundance in R software. Gene transcription data were analyzed by a 2 × 2 experimental factorial design using the PROC MIXED procedure of SAS. Principal coordinates analysis indicated that MFGM-fed groups exhibited an observable separation from CON-fed groups in terms of microbial community structures (P &amp;lt; 0.05). Firmicutes_A, Bacteroidota, and Firmicutes_D were the predominant phyla across all treatments, with average proportions to be 52.21 %, 24.36 %, and 18.46 %, respectively. At genus level, MFGM + Saline group down-regulated Corynebacterium by 88.00 % (q &amp;lt; 0.05) and Unclassified Muribaculaceae by 73.33 % (0.050.05). However, there was an MFGM × LPS interaction (P &amp;lt; 0.05) observed for nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor alpha, in which MFGM attenuated the LPS-induced increase in mRNA relative abundance (3.62 and 2.39 ± 0.38). In conclusion, dietary MFGM altered neonatal piglet intestinal microbiota and an important signaling molecule of the neuroinflammatory response following LPS challenge.

High carbohydrate diet decreases microbial diversity and increases IL-1β levels in mice colon.

Western diet is known to contribute to intestinal dysbiosis and the progression of inflammation. Although the Turkish diet has different macronutrient contents, the intestinal inflammatory disease incidences in Türkiye are comparable to Western countries. Thus, we hypothesized that high carbohydrate diets also contribute to inflammation of the colon. We compared diets with different macronutrient compositions and investigated their effects on colonic microbiota, cytokine, histology, and tight junction protein levels. High carbohydrate diet caused the lowest microbial diversity and is accompanied by the highest expression of interleukin-1β and claudin-1. A low carbohydrate diet with zero fiber resulted in the lowest inflammatory markers as well as the lowest occludin and claudin levels. Overall, our results indicate that carbohydrate and fiber contents of the diets are important contributors to colon health.

Complementary feeding in infants with cystic fibrosis: In vitro nutrient digestibility and impact on colonic microbiota

The aim was assessing macronutrient digestibility of common purees in the context of children with cystic fibrosis (CF) starting complementary feeding. A static in vitro digestion model was set up reproducing the conditions of infants with CF and healthy controls. Egg, chicken, infant formula and infant cereal were subjected to digestion individually and in combination with other ingredients. The resulting digesta was subjected to colonic fermentation with the faecal inoculum of an exclusively breast-fed infant with CF. Results showed overall low proteolysis and lipolysis, with positive interaction between egg and chicken with potato, vegetables, and olive oil. Contrarily, the combination of infant cereals and formula had a negative interaction. Notably, the dose of pancreatic enzymes had no effect on lipolysis. Purees rather than in individual foods impacted colonic microbiota, by reducing Bifidobacterium while increasing Veillonella. This study could guide future dietary recommendations for complementary feeding in infants with CF.

Characterizing functions of endogenous bile acid pools altered by Asbt-deficiency in the ileal transcriptional regulation.

Abstract Bile acids (BAs) are a diverse and abundant class of metabolites synthesized in the liver, absorbed in the ileum, and metabolized by the colonic microbiota. Besides the classical functions of BAs for lipid and vitamin absorptions in the small intestine (SI), BAs have emerged as potent immunoregulatory metabolites via interactions with G protein-coupled and nuclear receptors (NRs; e.g., FXR/NR1H4). Alterations of BA metabolism have been reported in human diseases, e.g., inflammatory bowel diseases. However, it remains unclear whether or how altered BA pools may influence the intestinal homeostasis and pathology. As in vivo studies cannot uncouple the regulatory functions of BAs from their impact on microbiota, I have developed a novel intestinal explant culture system, in which the ileal fragments can be treated with the endogenous BA pools from normal or diseased mice. The ileal, not colonic, fragments induced mRNA expressions of BA-targeted genes in the presence of (t)CDCA which is a representative and FXR-agonistic BA. Then, the fragments were cultured with the endogenous SI BA pools from healthy or Asbt-/- mice – which have altered BA pools. RNA-seq showed that some genes were similarly induced, but others were differentially regulated by each BA pools. In NR reporter assays, the BA pools from Asbt-/- mice potently activated RXRa, PXR, and ERb. Together, this study suggests abnormal BA pools differentially modulate the ileal environment via distinct NR pathways.

Prevotella enterotype associates with diets supporting acidic faecal pH and production of propionic acid by microbiota

Metabolism of dietary fibres by colon microbiota plays an important role for human health. Personal data from a nutrition study (57 subjects) were analysed to elucidate quantitative associations between the diet, faecal microbiome, organic acid concentrations and pH. Ratios of the predominant acids acetate, butyrate and propionate ranged from 1:0.67:0.27 to 1:0.17:0.36. Pectin-rich diets resulted in higher faecal acetate concentrations. Negative correlation between faecal pH and BSS was observed. Higher faecal pH and lower acid concentrations were related to the higher abundance of amino acid degrading Clostridium, Odoribacter and Eubacterium coprostanoligenes, which are weak carbohydrate fermenting taxa. Propionic acid correlated especially to high abundance of Prevotella and low abundance of proteobacteria. The acetate to propionate ratio of the Prevotella enterotype was about half of that of the Bacteroides enterotype. Based on the results we suggest the measurement of faecal pH and organic acid composition for research and diagnostic purposes.

Resident gut microbiota community determines the efficacy of soluble fiber in reducing adiposity.

Consumption of dietary fiber has been linked to several health benefits. Among these, dietary fiber breakdown through the process of anaerobic fermentation by the colonic microbiota leads to the production of beneficial metabolites, mainly short-chain fatty acids (acetate, propionate, and butyrate), which have been implicated in reduced calorie intake. Nevertheless, the link between gut microbiota and obesity remains unclear. We investigated the effects of dietary fibers on food intake and body weight gain in two independent but similarly designed studies in rats. In the first study, the inclusion of 10% w/w pectin, fructooligosaccharides or beta-glucan (n = 10/group) in the diets each significantly reduced body weight gain ('responders') compared to the cellulose control whereas, in a closely matched, but not fully identical study (n = 8/group), no effect of dietary fiber on body weight ('non-responders') was observed. The aim of this work was to explore the basis of this differential response between the two similarly designed and comparable studies, with a focus on the potential role of the gut microbiota in the control of food intake and body weight.

Analysis of the fermentation kinetics and gut microbiota modulatory effect of dried chicory root reveals the impact of the plant-cell matrix rationalizing its conversion in the distal colon.

Aim: The cell matrix of plant foods has received little attention in prebiotic fiber research. We aimed to understand the impact of the plant cell matrix in dried chicory root on its breakdown in the human gut to explain its reported beneficial effects on gut and metabolic health. Methods: We applied in vitro digestion and fermentation models together with an ex vivo gut barrier integrity model. Plant cell matrix intactness in the upper gastrointestinal tract was investigated by scanning electron microscopy. Colonic breakdown of inulin, and chicory root cubes and powder was assessed by gut microbiota analysis using 16S rRNA gene amplicon sequencing and determining the kinetics of changes in pH, gas, and short-chain fatty acid (SCFA) production. Finally, effects on gut barrier integrity were explored by exposing colonic biopsies to fermentation supernatants in an Ussing chamber model. Results: The plant cell matrix of dried chicory root cubes remained intact throughout upper gastrointestinal transit. Dried chicory root fermentation resulted in higher final relative abundances of pectin-degrading Monoglobus and butyrate-producing Roseburia spp. compared to inulin and a seven-fold increase in Bifidobacterium spp. in donors where these species were present. Dried chicory root cubes yielded similar total SCFAs but higher final butyrate levels than chicory root powder or isolated inulin with less gas produced. No uniform but donor-specific effects of fermentation supernatants on the maintenance of gut barrier integrity were detected. Conclusion: The intact plant cell matrix of dried chicory root affected its colonic breakdown kinetics and microbiota, underpinning its beneficial effect in vivo.

Nicotine improves DSS-induced colitis by inhibiting NLRP3 and altering gut microbiota

Ulcerative colitis (UC) is a chronic recurrent inflammatory disease affecting the rectum and colon. Numerous epidemiological studies have identified smoking as a protective factor for UC. Dysbiosis of intestinal microbiota and release of inflammatory factors are well-established characteristics associated with UC. Therefore, we have observed that nicotine exhibits the potential to ameliorate colitis symptoms in UC mice. Additionally, it exerts a regulatory effect on colonic microbiota dysbiosis by promoting the growth of beneficial bacteria while suppressing harmful bacteria. Combined in vivo and in vitro investigations demonstrate that nicotine primarily impedes the assembly of NLRP3, subsequently inhibiting downstream IL-1β secretion.

Colon microbiota and metabolite potential impact on tail fat deposition of Altay sheep.

Excessive tail fat deposition of Altay sheep caused great economic losses, and the current research results could not solve this problem well. Now, our research speculates that the tail fat deposition of Aletay sheep may be related to the abundance of Verrucomicrobia, Akkermansia, Bacteroides, metabolites phosphocholine, phosphatidylethanolamine, and growth hormone of serum. Further investigation of the interaction mechanism between these microbiota or metabolites and tail fat deposition is helpful in reducing tail fat deposition of Altay sheep and increasing the economic benefits of breeding farms.

Mangaba pulp fermented with Lacticaseibacillus casei 01 has improved chemical, technological, and sensory properties and positively impacts the colonic microbiota of vegan adults

This study aimed to evaluate the functional, technological, and sensory aspects of mangaba (Hancornia speciosa Gomes) fruit pulp fermented with the probiotic Lacticaseibacillus casei 01 (LC1) during refrigerated storage (7 °C, 28 days). The effects of the fermented mangaba pulp on the modulation of the intestinal microbiota of healthy vegan adults were also assessed. Mangaba pulp allowed high viability of LC1 during storage and after simulated gastrointestinal conditions (≥7 log CFU/g). The fermented mangaba pulp showed lower pH and total soluble solids, and higher titratable acidity, and concentrations of lactic, acetic, citric, and propionic acids during storage compared to non-fermented pulp. Also, it presented a higher concentration of bioaccessible phenolics and volatiles, and improved sensory properties (yellow color, brightness, fresh appearance, and typical aroma and flavor). Fermented mangaba pulp added to in vitro cultured colonic microbiota of vegan adults decreased the pH values and concentrations of maltose, glucose, and citric acid while increasing rhamnose and phenolic contents. Fermented mangaba pulp promoted increases in the abundance of Dorea, Romboutsia, Faecalibacterium, Lachnospira, and Lachnospiraceae ND3007 genera and positively impacted the microbial diversity. Findings indicate that mangaba pulp fermented with LC1 has improved chemical composition and functionality, inducing changes in the colonic microbiota of vegan adults associated with potential benefits for human health.

Gut Microbial Dysbiosis Differs in Two Distinct Cachectic Tumor-Bearing Models Consuming the Same Diet.

The impact of cancer cachexia on the colonic microbiota is poorly characterized. This study assessed the effect of two cachectic-producing tumor types on the gut microbiota to determine if a similar dysbiosis could be found. In addition, it was determined if a diet containing an immunonutrient-rich food (walnuts) known to promote the growth of probiotic bacteria in the colon could alter the dysbiosis and slow cachexia. Male Fisher 344 rats were randomly assigned to a semi-purified diet with or without walnuts. Then, within each diet group, rats were further assigned randomly to a treatment group: tumor-bearing ad libitum fed (TB), non-tumor-bearing ad libitum fed (NTB-AL), and non-tumor-bearing group pair-fed to the TB (NTB-PF). The TB group was implanted either with the Ward colon carcinoma or MCA-induced sarcoma, both transplantable tumor lines. Fecal samples were collected after the development of cachexia, and bacteria species were identified using 16S rRNA gene analysis. Both TB groups developed cachexia but had a differently altered gut microbiome. Beta diversity was unaffected by treatment (NTB-AL, TB, and NTB-PF) regardless of tumor type but was affected by diet. Also, diet consistently changed the relative abundance of several bacteria taxa, while treatment and tumor type did not. The control diet increased the abundance of A. Anaeroplasma, while the walnut diet increased the genus Ruminococcus. There were no common fecal bacterial changes characteristic of cachexia found. Diet consistently changed the gut microbiota, but these changes were insufficient to slow the progression of cachexia, suggesting cancer cachexia is more complex than a few gut microbiota shifts.