Microbiota Response Research Articles

Fecal and Sputum Microbiota and Treatment Response in Patients with Mycobacterium abscessus Pulmonary Disease.

The microbiota is a potential source of biomarkers for clinical outcomes in chronic respiratory conditions, but its role in Mycobacterium abscessus pulmonary disease (PD) remains unexplored. We aimed to identify microbial signatures in fecal and sputum microbiotas associated with treatment response in patients with M. abscessus PD. We conducted a cohort study prospectively enrolling patients undergoing antibiotic treatment for M. abscessus PD. Fecal and sputum samples were collected before, and 2 weeks and 6 months after, treatment initiation. 16S rRNA amplicon sequencing approach was used to characterize the microbiotas. After categorizing patients as early treatment responders and non-responders based on sputum culture results at 2 weeks, we elucidated the differences in their diversity and composition of microbiotas. Among 32 patients enrolled, 27 patients (median 66 years, 85.2% women, 48.1% with subspecies abscessus) were included for microbiota analysis. Fifteen patients (55.6%) achieved negative conversion at 2 weeks, which was maintained in 14 (93.3%) after 6 months. Alpha-diversity of the fecal microbiota after 2 weeks of treatment decreased significantly in responders, but not in non-responders (P=0.029). Increased abundance of Eubacterium hallii group in baseline fecal microbiota was indicative of unresponsiveness to antibiotics, whereas an increase in Enterococcus in fecal microbiota at week 2 was linked with favorable response. Increased abundance of Burkholderia-Caballeronia-Paraburkholderia and Porphyromonas in baseline, and decreased abundance of Rothia in week 2 sputum microbiota were also associated with good treatment response. In M. abscessus PD, changes in microbial diversity and compositional signatures vary with treatment response.

Validation of a Repurposed pH Monitoring Capsule for Cecal Applications Using Novel Synthetic Cecal Contents

Abstract This study presents a novel approach to monitoring pH changes in the cecum, a critical step toward understanding the dynamic interactions between the gut microbiota and probiotics. By repurposing the Bravo® capsule, originally designed for esophageal pH monitoring, we demonstrate its potential for accurate, continuous, and nonobstructive pH detection within a simulated cecal environment. To facilitate this investigation, we introduce the first synthetic cecal content (SCC) formulation. Our formulation closely mimics the mechanical properties of porcine cecal contents, particularly in terms of viscosity and shear response. This SCC recipe addresses a significant gap in the availability of simulated biological fluids for in vitro medical device testing. Rheometric analyses confirm the SCC's consistency with biological cecal contents, providing a cost-effective and efficient platform for preliminary device evaluations. Experimental results show that the Bravo® capsule can accurately detect pH changes within the SCC, closely matching readings from a handheld pH probe. The successful validation of the Bravo® capsule's performance in a simulated cecal environment, along with the development of a reliable SCC formulation, paves the way for future in vivo studies in porcine models. This research represents a significant advancement in the field of gut microbiome monitoring and holds promise for the development of targeted, microbiome-based therapeutics. By enabling real-tim/e, in situ analysis of the cecal microbiota's response to various interventions, this approach has the potential to revolutionize our understanding of the complex interplay between probiotics, diet, and gut health.

Research progress of probiotics and their protective strategy in the field of inflammatory bowel disease treatment: A review.

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease characterized by recurrent episodes and difficult-to-cure symptoms. Although the pathogenesis of IBD is closely related to host genetic susceptibility, intestinal microbiota, environmental factors, and immune responses, leading to mucosal damage and increased intestinal permeability. Intestinal mucosal injury in IBD patients causes pathogenic bacteria and pathogenic factors to invade the intestine, leading to disturb the structure and metabolic products of intestinal flora. Researchers have found that probiotics, as live microbial agents, can effectively inhibit the growth of pathogenic bacteria, regulate intestinal flora, optimize intestinal microecology, restore intestinal homeostasis, and promote intestinal mucosal repairing. During the oral delivery process, probiotics are susceptible to adverse physiological factors, leading to reduced bioavailability. Additionally, the oxidative stress microenvironment induced by intestinal mucosal damage makes it difficult for probiotics to colonize the intestinal tract of IBD patients, thereby affecting their probiotic effect. This research mainly introduces and reviews the advantages and disadvantages of probiotics and their protective strategies in the treatment of IBD, and prospects the future development trends of probiotics and their protective strategies. Probiotics can effectively inhibit the growth of harmful microorganisms, regulate the structure of the intestinal microbiota, and promote mucosal repairing, thereby reducing immune stress and alleviating intestinal inflammation, providing a new perspective for the treatment of IBD. The development of single-cell encapsulation technology not only effectively maintaining the biological activity of probiotics during oral delivery, but also endowing probiotics with additional biological functions naturally achieved through surface programming, which has multiple benefits for intestinal health.

The Variability of the Salivary Antimicrobial Peptide Profile: Impact of Lifestyle

Saliva is crucial in maintaining oral health; its composition reflects the body’s physiological and diseased state. Among salivary components, antimicrobial peptides (AMPs) stand out for their broad antimicrobial activities and role in modulating the oral microbiota and innate immune response. Local and systemic diseases can affect the levels of AMPs in saliva, making them attractive biomarkers. However, the large variability in their concentrations hampers their use in diagnostics. Knowledge of the various factors influencing the profile of salivary AMPs is essential for their use as biomarkers. Here, we examine how lifestyle factors such as physical activity, dietary supplementation, tobacco smoking, and psychological stress impact salivary AMP levels. By understanding these sources of variability, we can take a step forward in using AMPs for diagnostics and prognostics and develop new tailored and preventative approaches.

Dietary β-mannanase reduced post-weaning diarrhea of pigs by positively modulating gut microbiota and attenuating systemic immune responses

BackgroundAfter weaning, nursery pigs have difficulty digesting non-starch polysaccharides in their diets, which can result in growth and health problems. Among non-starch polysaccharides, β-mannan is easily found in various cereal grains that form the basis of livestock diets and interferes the digestion and utilization of nutrients. Supplementation of dietary β-mannanase in nursery diet can alleviate the negative effects on nutrient utilization efficiency caused by β-mannan and improve growth and health of pigs. This study was conducted to evaluate effects of dietary β-mannanase supplementation on growth performance, nutrient digestibility, intestinal morphology, fecal microbiota, and systemic immune responses of weaned pigs.ResultsDietary β-mannanase (MAN) improved average daily gain (P = 0.053), average daily feed intake (P < 0.05), and gain to feed ratio (P = 0.077) of pigs for 3 weeks after weaning and apparent total tract digestibility of crude protein (P = 0.060) and reduced post-weaning diarrhea (P < 0.05). The MAN did not affect the ileal morphology. Pigs fed with MAN had more diverse fecal microbiota based on the results of alpha diversity [the number of operational taxonomic units (OTUs; P = 0.061), Shannon (P = 0.071), and Simpson indices (P = 0.078)] and relative abundance of phylum Bacteroidetes (P = 0.064) and genus Prevotella (P < 0.05) than pigs fed control diet (CON). As a result of beta diversity, fecal microbiota was clustered (P < 0.05) into two distinct groups between dietary treatments. The MAN decreased (P < 0.05) packed cell volume (PCV), the number of white blood cells (WBC), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and cortisol of the pigs for 2 weeks after weaning compared with CON.ConclusionDietary β-mannanase reduced post-weaning diarrhea of pigs by positively modulating gut microbiota and attenuating systemic immune responses.

Response of the gut microbiota to changes in the nutritional status of red deer during winter

Unravelling abrupt alterations in the gut microbiota of wild species associated with nutritional stress is imperative but challenging for wildlife conservation. This study assessed the nutritional status of wild red deer during winter on the basis of changes in faecal nitrogen (FN) and urea nitrogen/creatinine (UN: C) levels and identified gut microbes associated with nutritional status via nutritional control experiments and metagenomic sequencing. The FN of wild red deer in winter 2022 was significantly lower than that in winter 2021 (p < 0.05, winter 2021: 1.37 ± 0.16% and winter 2022: 1.26 ± 0.22%), and the UN: C ratio increased (winter 2021: 2.19 ± 1.65 and winter 2022: 3.05 ± 3.50). Similar trends were found in late winter, which indicated greater nutritional pressure in winter (2022) and late winter. Compared with winter 2021, abundances of Ructibacterium and Butyrivibrio significantly increased, and Acetatifactor and Cuneatibacter significantly decreased during winter 2022 (p < 0.05). Compared with early winter, the cell growth and death pathways increased and lipid metabolism and its subpathway of secondary bile acid synthesis (ko00121) significantly decreased during late winter (p < 0.05), which was similar to the changes in malnourished experimental red deer. Abrupt alterations in the gut microbiota should receive increased attention when monitoring the nutritional health of wild ungulates. This study provides new insights and critical implications for the conservation of wild ungulate populations.

Impact of fermented wine lees on gut microbiota and metabolic responses in Guanling crossbred cattle

BackgroundThe addition of wine lees to diets can make up for the deficiencies caused by traditional forages in beef cattle farming. However, the effects of different wine lees ratios on average daily weight, gastrointestinal microbial community structure and metabolites in Guanling crossbred cattle have been rarely studied. This study assessed the effects of feeds containing wine lees on weight gain, gastrointestinal microbial community structure, and metabolites in Guanling crossbred cattle and elucidated the metabolic responses induced by wine lees. Eighteen cows were randomly assigned to receive fed concentrate (C group), feed containing 15% wine lees (group A), or feed containing 30% wine lees (group B) for 60 days.ResultsThe average daily weight gain of group A and group B increased by 76.75% and 57.65%, respectively, compared with group C. Microbial community analysis showed that wine lees increased the abundance of Prevotella_1 in the rumen, decreased the abundance of Ruminococcaceae UCG 011 and Lachnospiraceae_FCS020_group in the rumen, and increased the abundance of Tyzzerella_4, Family_Xlll_AD3011_group, Granulicella, and Eisenbergiella in the cecum. Metabolomics analyses showed that wine lees decreased the concentrations of indole-3-ethanol in the rumen, and complexity cecal metabolism. Notably, linoleic acid metabolism was significantly enriched in both the rumen and cecum. Mantel test analyses indicated that the adverse effects of WL were reduced by stimulating the metabolism of linoleic acid, α-linolenic acid, and tryptophan, and these changes were mediated by intestinal microorganisms. The Guanling cattle cecum was enriched for several unfavorable metabolic pathways when wine lees concentrations reached 30%, which increased the likelihood of intestinal lesions.ConclusionThis study shows that WL supplementation alters gut microbiota and metabolic pathways, improving cattle growth and health. Moderate WL levels (15%) enhance gut health and beneficial pathways (e.g., linoleic and alpha-linolenic acid metabolism). However, higher WL inclusion (30%) may activate adverse pathways, raising the risk of intestinal damage. To maximize benefits and minimize risks, WL levels should be carefully managed.

Dietary Chlorella vulgaris supplementation modulates health, microbiota and the response to oxidative stress of Atlantic salmon

Microalgae are emerging as functional feed ingredients in aquaculture due to their immune-stimulating and stress-modulating properties. We investigated the potential of the microalgae Chlorella vulgaris as a feed supplement to improve the health and modulate microbiota and stress responses of Atlantic salmon. Triplicate groups of Atlantic salmon (~ 126 g) were reared in a recirculating aquaculture system (RAS) at 15 °C and received diets supplemented with 2% (CV2) or 14% (CV14) spray-dried C. vulgaris daily, 14% once weekly (CV14w), or a control diet (CD) for 8 weeks. Subsequently, all groups were exposed to an acute one-hour peracetic acid (CH3CO3H; PAA) treatment, a commonly used disinfectant in RAS. While CV14 increased feed conversion (FCR) significantly, feeding the diets CV2 and CV14w improved protein retention efficiency. CV14 significantly modulated beta-diversity in the intestinal digesta and mucosa, but this effect was already visible in fish fed CV2. Feeding CV14 and, to a lesser degree, CV2 increased the relative abundances of Paenarthrobacter and Trichococcus in the digesta and mucosa, which are able to metabolize complex carbohydrates. However, the same diets reduced the abundance of the lactic acid bacteria Lactobacillus and Weissella in the digesta and Floricoccus in the mucosa. Peracetic acid exposure induced systemic stress (increase in plasma glucose and cortisol) and a local immune response in the gill, with the most prominent upregulation of several immune- and stress-regulated genes (clra, cebpb, marco, tnfrsf14, ikba, c1ql2, drtp1) 18 h after exposure in fish fed the control diet. Fish receiving CV14 once a week showed a reduced transcriptional response to PAA exposure. Catalase protein abundance in the liver increased following exposure to PAA, while superoxide dismutase abundance in the gill and liver was increased in response to C. vulgaris inclusion before stress. Overall, the results highlight that a high (14%) inclusion rate of C. vulgaris in feed for Atlantic salmon impairs feed conversion and shifts the intestinal microbiota composition in digesta and mucosa. Weekly feeding of C. vulgaris proves a viable approach in improving protein retention and improving transcriptional resilience towards oxidative stress in increasingly intensive production systems. Thereby this study may motivate future studies on optimizing temporal feeding schedules for health-promoting aquafeeds.

Growth, biochemical indexes, and intestinal microbiota response of red tilapia (Oreochromis spp.) under different densities and feeding frequencies in the land-based aquaculture tank

Red tilapia (Oreochromis spp.) has been favored by farmers in recent years because of its superior growth performance and competitive market price, but there is a lack of experimental data related to growth and health of red tilapia in land-based aquaculture tanks. In this study, red tilapia (initial weight 27.62 ± 2.43 g) was cultured with three stocking densities (30, 40, or 50 fish/m3, named 30F,40F and 50F) in the culture mode for 60 days, including two feeding frequencies (2 or 3 times/day, named 2 T and 3 T), and various growth and metabolic parameters were assessed along with the intestinal microbiome analysis. The 30 fish/m3 groups achieved the better weigh gain rate and specific growth rate (p < 0.05). The growth rate and condition factor of 40F groups were close to those of 30F groups, the yield of 40F groups were not significantly different from that of 50F groups (p > 0.05), and it had the highest survival rate (p < 0.05). The 3 T groups has a higher growth rate and yield but also has a higher rate of feed conversion (p < 0.05). The 30F groups had higher lipase levels, but a higher fat content in this group, more lipids were observed in the liver, and resulted in higher blood glucose levels (p < 0.05). The 40F groups showed healthier physiological and biochemical indicators, as its total cholesterol, lysozyme and antioxidant enzymes levels were similar to those of the 30F groups (p > 0.05), alkaline phosphatase, amylase and trypsin levels were higher than those of the other groups, and aspartate transaminase levels were the lowest (p < 0.05). The 50F groups had higher cortisol, alanine transaminase and malondialdehyde levels, lower lysozyme and digestive enzyme activities, and blood cell infiltration in the liver (p < 0.05). In terms of different feeding frequencies, the 3 T groups had higher crude protein content, catalase and total superoxide dismutase levels, wider villus width and lower blood glucose level, while the 2 T groups had higher triglyceride, total cholesterol, lysozyme, alkaline phosphatase and some digestive enzymes activities (p < 0.05). From the perspective of intestinal microbiota. The 40F groups had a better intestinal flora, and 40F-3T groups observed a better balance of flora, while 40F-2T groups had more digestion-related flora. Considering the growth rate, health status, and yield, the optimum culture condition was determined to be stocking density of 40 fish/m3, and feedings 3 times/day were recommended. The experiment provided theoretical basis and experimental data for red tilapia culture in land-based aquaculture tank mode.

Effect of fermented total mixed rations on rumen microbial communities and serum metabolites in lambs

AbstractBackgroundDiet regulates rumen microbiota, which in turn affects animal health. The present study evaluated the response of rumen microbiota and the immune system of lambs to a fermented total mixed ration diet.MethodsA total of 30 lambs were assigned into two groups: a group fed an unfermented high‐fiber diet (total mixed ration [TMR]) and a group fed an fermented low‐fiber diet (fermented TMR [FTMR]).ResultsThe results showed that FTMR markedly (p &lt; 0.05) increased average daily gain and dry matter intake compared to TMR. The FTMR diet increased the relative abundance of Veillonellaceae_UCG‐001 and decreased the diversity of undesirable microbiota despite stable overall microbial community diversity. Serum metabolomic analysis combined with enrichment analysis showed that serum metabolites were affected by the FTMR and metabolic pathways, and the FTMR diet significantly (p &lt; 0.05) influenced amino acid metabolism of lambs. There was a decrease in inflammatory factors in the FTMR treatment, indicating that inflammatory factors followed the same trajectory as changes in microbial community structure and function.ConclusionsOverall, the FTMR diet reduced undesirable microbiota diversity, thereby regulating host amino acid metabolism and improving immune status.

Sequential early-life viral infections modulate the microbiota and adaptive immune responses to systemic and mucosal vaccination.

Increasing evidence points to the microbial exposome as a critical factor in maturing and shaping the host immune system, thereby influencing responses to immune challenges such as infections or vaccines. To investigate the effect of early-life viral exposures on immune development and vaccine responses, we inoculated mice with six distinct viral pathogens in sequence beginning in the neonatal period, and then evaluated their immune signatures before and after intramuscular or intranasal vaccination against SARS-CoV-2. Sequential viral infection drove profound changes in all aspects of the immune system, including increasing circulating leukocytes, altering innate and adaptive immune cell lineages in tissues, and markedly influencing serum cytokine and total antibody levels. Beyond changes in the immune responses, these exposures also modulated the composition of the endogenous intestinal microbiota. Although sequentially-infected mice exhibited increased systemic immune activation and T cell responses after intramuscular and intranasal SARS-CoV-2 immunization, we observed decreased vaccine-induced antibody responses in these animals. These results suggest that early-life viral exposures are sufficient to diminish antibody responses to vaccination in mice, and highlight the potential importance of considering prior microbial exposures when investigating vaccine responses.

Yeast β-glucan attenuates dextran sulfate sodium-induced colitis: Involvement of gut microbiota and short-chain fatty acids

Yeast β-glucan intervention offers a promising strategy for managing colitis; however, the mechanisms remain unknown. In the present work, the protective effects of yeast β-glucan on DSS-induced colitis in mice was evaluated, focusing on its interaction with gut microbiota. The result showed yeast β-glucan significantly alleviated colitis symptoms, evidenced by reduced weight loss, lower disease activity index (DAI) scores, and minimized intestinal damage. It enhanced intestinal barrier integrity via upregulation of tight junction proteins, suppressed lipopolysaccharide (LPS) release, and decreased pro-inflammatory cytokines production. Additionally, yeast β-glucan boosted short-chain fatty acids (SCFAs) production, and activated their receptors, increased the relative abundances of beneficial microbes like Lactobacillus and Lachnospiraceae_UCG-006. Transcriptomic analyses suggest that yeast β-glucan mitigates inflammation by downregulating gene expression related to IL-17 pathway. Our findings highlight potential of yeast β-glucan as a therapeutic agent for colitis through modulation of gut microbiota and inflammatory responses.

Responses of soil microbial metabolism, function and soil quality to long-term addition of organic materials with different carbon sources

Biochar and green manure have been widely applied in agricultural production and are important means to achieve sustainable agriculture. However, there is limited research systematically and comprehensively exploring the response of soil microbiota and the changes in soil metabolomics after the addition of two different carbon source amendments to the soil, and the differential mechanisms of soil metabolomics between them remain unclear. In this study, a long-term field experiment (initiated in 2019) was conducted to investigate the effects of biochar and green manure application on soil nutrients and soil functions driven by soil microbes. Compared to the pure fertilizer treatment, biochar increased soil total carbon by 14.54% to 27.04% and soil available potassium by 4.67% to 27.46%. Ryegrass significantly increased soil available phosphorus and organic matter. Under different fertilization regimes, the ecological niches of soil microbes changed significantly. Network analysis revealed that long-term ryegrass returning reduced the complexity of soil microbial networks. Ryegrass and biochar increased dispersal limitation in fungal assemblages (reaching 93.33% and 86.67%, respectively), with biochar particularly enhancing variable selection in bacterial assemblages (accounting for 53.33%). Variation partitioning analysis based on redundancy analysis indicated that humic substances had the highest explanatory power for microbial community variation, with humic substances explaining 38.49% of bacteria and 52.19% of fungi variation. The ryegrass treatment mainly changed the abundance of carbohydrates (CH), amines (AM), c (AH), and lipids (LP), while the BC treatment mainly altered the abundance of organic acids (AC), amines (AM), and carbohydrates (CH). Meanwhile, both treatments significantly reduced the bisphenol A, one of the soil pollutants. Ryegrass incorporation significantly increased the abundance of genes related to soil C, N, P, and S cycling, especially genes involved in carbon decomposition, while biochar significantly enhanced the abundance of nitrogen fixation genes nifH and Hao in soil. Random forest model results indicated that carbohydrates, alcohols, aromatics (AR), and ester (ES) were the main categories of metabolites in soil influenced by differential microbes, and Finegoldia served as a common important metabolic driving species. In summary, this study reveals the processes of soil function, microbial community succession, and metabolism driven by ryegrass and biochar, providing important insights for optimizing soil management and improving soil quality.Graphical

Gastrointestinal microbiota and metabolites responses to dietary cereal grains in an adult pig model.

Corn (C), wheat (W), and paddy rice (PR) are important energy sources and are commonly used in feed production for swine. This study mainly focuses on the variation and regularities of microbiota and metabolites in the gastrointestinal tract (GIT) of pigs in response to C, W, and PR. A total of 18 pigs were allotted into three dietary groups with six replicated pigs and received diets containing C, W, or PR as the sole energy source, respectively. The results showed that digestive parts significantly affected the diversity of microbial communities. Cereal grain sources significantly influenced the β-diversity of microbial communities in the colon and rectum. Campylobacterota and Proteobacteria are mainly distributed in the duodenum, Lactobacillus in the jejunum, and Bacteroidota in the colon and rectum. The W diet increased the Bacteroidota, Spirochaetota, and Prevotellaceae_NK3B31_group abundances and showed the highest concentrations of all short-chain fatty acids (SCFAs) in the hindgut. Fibrobacterota, Bacteroidota, Spirochaetota, Prevotellaceae_NK3B31_group, Prevotella, and Treponema in the colon or rectum were positively correlated with acetate, propionate, butyrate, and total SCFAs. These findings suggested that aerobic bacteria and facultative anaerobes in the foregut will gradually be replaced by anaerobes in the hindgut. The W diet had the best fermentability and was beneficial to the colonization of microbial communities that mainly used carbohydrates. The hindgut flora of the PR diet group may be more balanced with fewer potential pathogenic bacteria. Many microbial communities have been identified to contribute positively to the SCFA production of the hindgut. Collectively, our study revealed the spatial variation regularities of GIT microbial communities in an adult pig model and provided new insights into GIT microbiota and responses of metabolites to cereal grain diets.

Investigating the Effect of Bacilli and Lactic Acid Bacteria on Water Quality, Growth, Survival, Immune Response, and Intestinal Microbiota of Cultured Litopenaeus vannamei.

Shrimp is one of the most important aquaculture industries. Therefore, we determined the effect of nitrifying-probiotic bacteria on water quality, growth, survival, immune response, and intestinal microbiota of Litopenaeus vannamei cultured without water exchange. In vitro, only Bacillus licheniformis used total ammonia nitrogen (TAN), nitrites, and nitrates since nitrogen bubbles were produced. TAN decreased significantly in the treatments with B. licheniformis and Pediococcus pentosaceus and Leuconostoc mesenteroides, but no differences were observed in nitrites. Nitrates were significantly higher in the treatments with bacteria. The final weight was higher only with bacilli and bacilli and LAB treatments. The survival of shrimp in the bacterial treatments increased significantly, and superoxide anion increased significantly only in lactic acid bacteria (LAB) treatment. The activity of phenoloxidase decreased significantly in the treatments with bacteria compared to the control. Shrimp treated with bacilli in the water showed lower species richness. The gut bacterial community after treatments was significantly different from that of the control. Linoleic acid metabolism was positively correlated with final weight and superoxide anion, whereas quorum sensing was correlated with survival. Thus, bacilli and LAB in the water of hyperintensive culture systems act as heterotrophic nitrifers, modulate the intestinal microbiota and immune response, and improve the growth and survival of shrimp. This is the first report on P. pentosaceus and L. mesenteroides identified as nitrifying bacteria.

Functional Effects of Probiotic Lactiplantibacillus plantarum in Alleviation Multidrug-Resistant Escherichia coli-Associated Colitis in BALB/c Mice Model.

Multidrug-resistant Escherichia coli (MDR-E. coli) is a global health concern. Lactic acid bacteria (LAB) are important probiotics that have beneficial effects on health, and in recent years, their influences in preventing foodborne pathogens-induced colitis have attracted much attention. Therefore, this study aimed to investigate the oral administration of Lactiplantibacillus plantarum NWAFU-BIO-BS29 as an emerging approach to alleviate MDR-E. coli-induced colitis in BALB/c mice model. To illustrate the mode of action of NWAFU-BIO-BS29 interventions with the gut microbiota and immune responses, the changes on the colonic mucosal barrier, regulatory of the gene expressions of inflammatory cytokines, re-modulating the intestinal microflora, and changes in physiological parameters were studied. The results indicated that daily supplementation of 200 µL fresh bacteria for 7days had ameliorated the associated colitis and partially prevented the infection. The modes of action by ameliorating the inflammatory response, which destructed villous and then affected the intestinal barrier integrity, reducing the secretion of interleukins (6 and β) and tumor necrosis factor (TNF-α) in serum by 87.88-89.93%, 30.73-35.98%, and 19.14-22.32%, respectively, enhancing the expressions of some epithelial integrity-related proteins in the mouse mucous layer of mucins 2 and 3, Claudin-1, and Occludin by 130.00-661.85%, 27.64-57.35%, 75.52-162.51%, and 139.36-177.73%, respectively, and 56.09-73.58% for toll-like receptor (TLR4) in colon tissues. Notably, the mouse gut microbiota analysis showed an increase in the relative abundance of beneficial bacteria, including Lactobacillus, Bacteriodales bacterium, Candidatus Saccharimonas, Enterorhabdus, and Bacilli. Furthermore, the probiotic promoted the proliferation of epithelia and goblet cells by increasing short-chain fatty acids (SCFAs) levels by 19.23-31.39%. In conclusion, L. plantarum NWAFU-BIO-BS29 has potential applications and can be considered a safe dietary supplement to ameliorate the colitis inflammation symptoms of MDR-E. coli infection.

Interaction and effects of temperature preference under a controlled environment on the diversity and abundance of the microbiome in Lutzomyia longipalpis (Diptera: Psychodidae)

Characterization of the temperature effects on the abundance and richness of the microbiota of Lutzomyia longipalpis, insect vector of Leishmania infantum in America, is an aspect of pivotal importance to understand the interactions between temperature, bacteria, and Leishmania infection. We developed and used a customized device with a temperature gradient (21–34 °C) to assess the temperature preferences of wild females of Lu. longipalpis collected in a rural area (Ricaurte, Cundinamarca, Colombia). Each replicate consisted of 50 females exposed to the gradient for an hour. At the end of the exposure time, insects were collected and separated by the temperature ranges selected varying from 21 °C to 34 °C. They were organized in 17 pools from which total DNA extracts were obtained, and samples were subjected to 16S rRNA amplicon sequencing analyzes. The most abundant phyla across the different temperature ranges were Proteobacteria (17.22–90.73 %), Firmicutes (5.99–77.21 %) and Actinobacteria (1.56–59.85 %). Results also showed an abundance (30 % to 57.36 %) of Pseudomonas (mainly at temperatures of 21–29 °C and 34 °C) that decreased to 6.55 %-13.20 % at temperatures of 31–33 °C, while Bacillus increase its abundance to 67.24 % at 29–33 °C. Serratia also had a greater representation (49.79 %), specifically in sand flies recovered at 25–27 °C. No significant differences were found at α-diversity level when comparing richness using the Shannon-Wiener, Simpson, and Chao1 indices, while β-diversity differences were found using the Bray-Curtis index (F-value of 3.5073, p-value < 0.013, R-squared of 0,4889), especially in the groups of Lu. longipalpis associated at higher temperatures (29–33 °C). It was also possible to detect the presence of endosymbionts such as Spiroplasma and Arsenophonus in the range of 29–33 °C. Rickettsia was only detected in Lu. longipalpis sand flies recovered between 25–27 °C. It was possible to characterize Lu. longipalpis microbiota in response to intraspecific temperature preferences and observe changes in bacterial communities and endosymbionts at different ranges of said environmental variable, which may be important in its vector competence and environmental plasticity to adapt to new climate change scenarios.

Responses of survival, antioxidant system and intestinal microbiota of native snail Bellamya purificata to the invasive snail Pomacea canaliculata

Pomacea canaliculata is one of the most successful invader in worldwide, adversely affecting native ecosystem through direct predation or indirect competition, while the mechanism of indirect effects on native species remain poorly understood. To clarify the effects of P. canaliculata on the native near-niche species, Bellamya purificata, a widespread freshwater gastropod in China, was selected as the research subject. The changes of mortality, histology, antioxidant system as well as the intestinal flora diversity of B. purificata were explored in present study. The results showed that the median lethal dose of P. canaliculata culture solution for B. purificata was 23.76 ind/L and a concentration-dependent damage of both the gonad and hepatopancreas were observed, the gonadal villi were dissolved and the hepatopancreas cells were broken at 20 ind/L. Furthermore, different concentrations of P. canaliculata culture solution leading to the antioxidant damage on the enzyme or non-enzyme systems of B. purificata at various degrees. Additionally, a decrease in the diversity of the intestinal flora was observed, accompanied by an increase in the abundance of pathogenic bacteria such as Pseudomonas and Aeromonas after the exposure of the culture solution of P. canaliculata. Last, after being recovered in freshwater for 24 h, the antioxidant damage of B. purificata and the disturbance of intestinal flora diversity were still not recovered especially in the high concentration group. The indirect competitive mechanism of P. canaliculata culture solution on B. purificata were explored from the aspects of tissue, biochemical level and intestinal flora, which enriched the research of P. canaliculata invasion on native snails in China, and provided new insights for the study of the invasion strategy of P. canaliculata.

Dietary grape proanthocyanidins modulate gut microbiome and neuroendocrine response in dogs

This research investigates the properties of grape proanthocyanidins (GPAC) in dogs of varying ages and breeds housed in the kennel, with a focus on the interaction between GPAC and gut microbiota. The study also examines the impact of GPAC on endocrine responses measured in saliva and hair. Faecal samples were collected before administration (T0), as well as 14 days (T14) and 28 days (T28) thereafter, with dogs subjected to a control diet (D0), and a diet supplemented with 1 mg/kg body weight (D1), or 3 mg/kg body weight (D3) of GPAC. The alpha diversity, as measured by the Shannon index, remained stable between diets at the study's outset (T0), after 14 days (T14), and 28 days (T28). Differences were observed in the Shannon index between T0 and T14 (P < 0.05), while the variation was lower between T0 and T28 (P < 0.10). In essence, the beta diversity of microbial composition remained unaffected by the variation of GPAC doses at T0, T14, and T28. Instead, specific taxa were affected by the addition of GPAC. The relative abundance (RA, %) of Dorea increased from T14 to T28, with a notable rise in the D1 group (P ≤ 0.05). The RA of the Clostridium genus also increased, particularly in D3 at T28 (P ≤ 0.05). After 28 days, there was a significant increase in the RA of Clostridium perfringens, rising from median of 6.15 at D0 to 10.58 at D1 and further increasing to 11.53 at D3 (P<0.05). GPAC supplementation influenced the RA of the Fusobacteriaceae family at T28, with D3 showing a lower value than D1 and D0 (P ≤ 0.05). The RA of Enterobacteriaceae family varied under different dietary conditions at T14, with a lower value at D3 (P ≤ 0.05). Salivary concentrations of kynurenine varied between diets at T28, with D0 having the highest concentration. The serotonin to cortisol ratios were higher (P<0.05) at T28 for D3, indicating a potentially more favourable balance with this level of supplementation compared to D0 and D1. Our study provides insights into the dynamic interplay between GPAC, faecal microbiota, and endocrine responses in dogs, shedding light on potential effects associated with the supplementation.

Dynamic response of the intestinal microbiome to Eimeria maxima-induced coccidiosis in chickens.

We have observed for the first time the dynamic response of the intestinal microbiota to Eimeria maxima infection, synchronized with its life cycle. Minimal changes occur in both the ileal and cecal microbiota during early infection, while significant alterations coincide with acute infection and disruption of the intestinal mucosal lining. As animals recover from coccidiosis, the intestinal microbiota largely returns to normal. E. maxima-induced intestinal inflammation likely creates an environment conducive to the growth of aerotolerant anaerobes such as Lactobacillus, as well as facultative anaerobes such as Escherichia, Enterococcus, and Staphylococcus, while suppressing the growth of obligate anaerobes such as short-chain fatty acid-producing bacteria. These findings expand our understanding of the temporal dynamics of the microbiota structure during Eimeria infection and offer insights into the pathogenesis of coccidiosis, supporting the rationale for microbiome-based strategies in the control and prevention of this condition.