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The immune system employs recognition tools to communicate with its microbial evolutionary partner. Among all the methods of microbial perception, T cells enable the widest spectrum of microbial recognition resolution, ranging from the crudest detection of whole groups of microbes to the finest detection of specific antigens. The application of this recognition capability to the crucial task of combatting infections has been the focus of classical immunology. We now appreciate that the coevolution of the immune system and the microbiota has led to development of a lush immunological decision tree downstream of microbial recognition, of which an inflammatory response is but one branch. In this review we discuss known T cell-microbe interactions in the gut and place them in the context of an algorithmic framework of recognition, context-dependent interpretation, and response circuits across multiple levels of microbial recognition resolution. The malleability of T cells in response to the microbiota presents an opportunity to edit immune response cellularity, identity, and functionality by utilizing microbiota-controlled pathways to promote human health.
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Microbiota , Linfócitos T , Animais , HumanosRESUMO
Nociceptive pain is a hallmark of many chronic inflammatory conditions including inflammatory bowel diseases (IBDs); however, whether pain-sensing neurons influence intestinal inflammation remains poorly defined. Employing chemogenetic silencing, adenoviral-mediated colon-specific silencing, and pharmacological ablation of TRPV1+ nociceptors, we observed more severe inflammation and defective tissue-protective reparative processes in a murine model of intestinal damage and inflammation. Disrupted nociception led to significant alterations in the intestinal microbiota and a transmissible dysbiosis, while mono-colonization of germ-free mice with Gram+Clostridium spp. promoted intestinal tissue protection through a nociceptor-dependent pathway. Mechanistically, disruption of nociception resulted in decreased levels of substance P, and therapeutic delivery of substance P promoted tissue-protective effects exerted by TRPV1+ nociceptors in a microbiota-dependent manner. Finally, dysregulated nociceptor gene expression was observed in intestinal biopsies from IBD patients. Collectively, these findings indicate an evolutionarily conserved functional link between nociception, the intestinal microbiota, and the restoration of intestinal homeostasis.
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Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Nociceptores/fisiologia , Substância P , Disbiose , InflamaçãoRESUMO
Microbe-derived acetate activates the Drosophila immunodeficiency (IMD) pathway in a subset of enteroendocrine cells (EECs) of the anterior midgut. In these cells, the IMD pathway co-regulates expression of antimicrobial and enteroendocrine peptides including tachykinin, a repressor of intestinal lipid synthesis. To determine whether acetate acts on a cell surface pattern recognition receptor or an intracellular target, we asked whether acetate import was essential for IMD signaling. Mutagenesis and RNA interference revealed that the putative monocarboxylic acid transporter Tarag was essential for enhancement of IMD signaling by dietary acetate. Interference with histone deacetylation in EECs augmented transcription of genes regulated by the steroid hormone ecdysone including IMD targets. Reduced expression of the histone acetyltransferase Tip60 decreased IMD signaling and blocked rescue by dietary acetate and other sources of intracellular acetyl-CoA. Thus, microbe-derived acetate induces chromatin remodeling within enteroendocrine cells, co-regulating host metabolism and intestinal innate immunity via a Tip60-steroid hormone axis that is conserved in mammals.
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Proteínas de Drosophila/metabolismo , Drosophila melanogaster/imunologia , Células Enteroendócrinas/metabolismo , Microbioma Gastrointestinal/imunologia , Histona Acetiltransferases/metabolismo , Intestinos/imunologia , Acetatos/imunologia , Acetilcoenzima A/metabolismo , Animais , Montagem e Desmontagem da Cromatina/fisiologia , Drosophila melanogaster/microbiologia , Ecdisona/metabolismo , Imunidade Inata/imunologia , Intestinos/microbiologia , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Interferência de RNA , Transdução de Sinais/imunologia , Taquicininas/metabolismoRESUMO
Interactions between the nervous and immune systems enable the gut to respond to the variety of dietary products that it absorbs, the broad spectrum of pathogens that it encounters, and the diverse microbiome that it harbors. The enteric nervous system (ENS) senses and reacts to the dynamic ecosystem of the gastrointestinal (GI) tract by translating chemical cues from the environment into neuronal impulses that propagate throughout the gut and into other organs in the body, including the central nervous system (CNS). This review will describe the current understanding of the anatomy and physiology of the GI tract by focusing on the ENS and the mucosal immune system. We highlight emerging literature that the ENS is essential for important aspects of microbe-induced immune responses in the gut. Although most basic and applied research in neuroscience has focused on the brain, the proximity of the ENS to the immune system and its interface with the external environment suggest that novel paradigms for nervous system function await discovery.
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Sistema Nervoso Central/imunologia , Sistema Nervoso Entérico , Microbioma Gastrointestinal , Trato Gastrointestinal/fisiologia , Sistema Imunitário/imunologia , Imunidade nas Mucosas , Intestinos/imunologia , Animais , Exposição Ambiental , Trato Gastrointestinal/anatomia & histologia , Interações Hospedeiro-Patógeno , Humanos , NeuroimunomodulaçãoRESUMO
Coccidia of the genus Eimeria are specialized intracellular parasitic protozoa that cause severe coccidiosis when they infect their hosts. Animals infected with Eimeria develop clinical symptoms, such as anorexia, diarrhea, and hematochezia, which can even cause death. Although the current preferred regimen for the treatment of coccidiosis is antibiotics, this treatment strategy is limited by the ban on antibiotics and the growing problem of drug resistance. Therefore, the exploration of alternative methods for controlling coccidiosis has attracted much attention. Lactobacillus plantarum has been shown to have many beneficial effects. In this study, L. plantarum M2 was used as a research object to investigate the effect of L. plantarum on intestinal inflammation induced by infection with Eimeria falciformis in mice by detecting indicators, such as oocyst output, serum cytokines, and the intestinal microbiota. Compared with that in the infection group, the percent weight loss of the mice that were administered with L. plantarum M2 was significantly reduced (P < 0.05). Supplemented L. plantarum M2 and probiotics combined with diclazuril can reduce the total oocyst output significantly (P < 0.05, P < 0.001). L. plantarum M2 had outstanding performance in maintaining intestinal barrier function, and the levels of the mucin MUC1 and the tight junction protein E-cadherin were significantly elevated (P < 0.01, P < 0.05). Studies have shown that probiotic supplementation can alleviate adverse reactions after infection and significantly improve intestinal barrier function. In addition, probiotics combined with diclazuril could optimize the partial efficacy of diclazuril, which not only enhanced the effect of antibiotics but also alleviated their adverse effects. This study expands the application of probiotics, provides new ideas for alternative strategies for coccidia control, and suggests a basis for related research on lactobacilli antagonizing intracellular pathogen infection.IMPORTANCECoccidia of the genus Eimeria are specialized intracellular parasitic protozoa, and the current preferred regimen for the treatment of coccidiosis is antibiotics. However, due to antibiotic bans and drug resistance, the exploration of alternative methods for controlling coccidiosis has attracted much attention. In this work, we focused on Lactobacillus plantarum M2 and found that probiotic supplementation can alleviate adverse reactions after infection and improve intestinal barrier function. This study proposes the possibility of using lactic acid bacteria to control coccidiosis, and its potential mechanism needs further exploration.
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Coccidiose , Eimeria , Lactobacillus plantarum , Probióticos , Animais , Coccidiose/parasitologia , Eimeria/efeitos dos fármacos , Probióticos/uso terapêutico , Probióticos/administração & dosagem , Camundongos , Citocinas/sangue , Citocinas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Oocistos , Modelos Animais de Doenças , Nitrilas , TriazinasRESUMO
In recent years, further evidence has emerged regarding the involvement of extracellular vesicles in various human physiopathological conditions such as Alzheimer's disease, Parkinson's disease, irritable bowel syndrome, and mental disorders. The biogenesis and cargo of such vesicles may reveal their impact on human health nd disease and set the underpinnings for the development of novel chemical compounds and pharmaceuticals. In this review, we examine the link between bacteria-derived exosomes in the gastrointestinal tract and mental disorders, such as depression and anxiety disorders. Crucially, we focus on whether changes in the gut environment affect the human mental state or the other way around. Furthermore, the possibility of handling bacteria-derived exosomes as vectors of chemicals to treat such conditions is examined.
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Low back pain is a health problem that represents the greatest cause of years lived with disability. This research seeks to evaluate the bacterial composition of the intestinal microbiota of two similar groups: one with chronic low back pain (PG) and the control group (CG). Clinical data from 73 participants and bacterial genome sequencing data from stool samples were analyzed. There were 40 individuals in PG and 33 in CG, aged between 20 and 50 years and with a body mass index of up to 30 kg/m2. Thus, the intragroup alpha diversity and intergroup beta diversity were analyzed. The significant results (p < 0.05) showed greater species richness in PG compared to CG. Additionally, a greater abundance of the species Clostridium difficile in PG was found along with 52 species with significantly different average relative abundances between groups (adjusted p < 0.05), with 36 more abundant species in PG and 16 in CG. We are the first to unveil significant differences in the composition of the intestinal bacterial microbiota of individuals with chronic low back pain who are non-elderly, non-obese and without any other serious chronic diseases. It could be a reference for a possible intestinal bacterial microbiota signature in chronic low back pain.
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Klebsiella aerogenes (K. aerogenes, KA) is a gram-negative opportunistic pathogen from the Klebsiella species and the Enterobacteriaceae family. However, the impact of K. aerogenes on colorectal cancer (CRC) remains uncertain. A colitis-associated tumorigenesis animal model was established by administering azoxymethane (AOM) and dextran sulfate sodium (DSS) to C57BL/6J mice. The concentration of K. aerogenes gavage in mice was 109 cfu. The study measured the following parameters: tumor formation (number and size), intestinal permeability (MUC2, ZO-1, and Occludin), colonic inflammation (TNF-α, IL-1ß, IL-6, and IL-10), proliferation and the fluctuation of the intestinal flora. Under the AOM/DSS-treated setting, K. aerogenes colonization worsened colitis by exacerbating intestinal inflammatory reaction and destroying the mucosal barrier. The intervention markedly augmented the quantity and dimensions of neoplasm in the AOM/DSS mice, stimulated cellular growth, and impeded cellular programmed cell death. In addition, K. aerogenes exacerbated the imbalance of the intestinal microbiota by elevating the abundance of Pseudomonas, Erysipelatoclostridium, Turicibacter, Rikenella, and Muribaculum and leading to a reduction in the abundance of Odoribacter, Alloprevotella, Roseburia, and Lachnospiraceae_NK4A136_group. The presence of K. aerogenes in AOM/DSS-treated mice promoted tumorigenesis, worsened intestinal inflammation, disrupted the intestinal barrier, and caused disturbance to the gut microbiota.
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Colite , Enterobacter aerogenes , Animais , Camundongos , Azoximetano/toxicidade , Azoximetano/metabolismo , Camundongos Endogâmicos C57BL , Colite/patologia , Colo/patologia , Inflamação/patologia , Carcinogênese/patologia , Transformação Celular Neoplásica/patologia , Bacteroidetes , Sulfato de Dextrana/toxicidade , Modelos Animais de DoençasRESUMO
BACKGROUND: Ulcerative colitisis (UC) classified as a form of inflammatory bowel diseases (IBD) characterized by chronic, nonspecific, and recurrent symptoms with a poor prognosis. Common clinical manifestations of UC include diarrhea, fecal bleeding, and abdominal pain. Even though anti-inflammatory drugs can help alleviate symptoms of IBD, their long-term use is limited due to potential side effects. Therefore, alternative approaches for the treatment and prevention of inflammation in UC are crucial. METHODS: This study investigated the synergistic mechanism of Lactobacillus plantarum SC-5 (SC-5) and tyrosol (TY) combination (TS) in murine colitis, specifically exploring their regulatory activity on the dextran sulfate sodium (DSS)-induced inflammatory pathways (NF-κB and MAPK) and key molecular targets (tight junction protein). The effectiveness of 1 week of treatment with SC-5, TY, or TS was evaluated in a DSS-induced colitis mice model by assessing colitis morbidity and colonic mucosal injury (n = 9). To validate these findings, fecal microbiota transplantation (FMT) was performed by inoculating DSS-treated mice with the microbiota of TS-administered mice (n = 9). RESULTS: The results demonstrated that all three treatments effectively reduced colitis morbidity and protected against DSS-induced UC. The combination treatment, TS, exhibited inhibitory effects on the DSS-induced activation of mitogen-activated protein kinase (MAPK) and negatively regulated NF-κB. Furthermore, TS maintained the integrity of the tight junction (TJ) structure by regulating the expression of zona-occludin-1 (ZO-1), Occludin, and Claudin-3 (p < 0.05). Analysis of the intestinal microbiota revealed significant differences, including a decrease in Proteus and an increase in Lactobacillus, Bifidobacterium, and Akkermansia, which supported the protective effect of TS (p < 0.05). An increase in the number of Aspergillus bacteria can cause inflammation in the intestines and lead to the formation of ulcers. Bifidobacterium and Lactobacillus can regulate the micro-ecological balance of the intestinal tract, replenish normal physiological bacteria and inhibit harmful intestinal bacteria, which can alleviate the symptoms of UC. The relative abundance of Akkermansia has been shown to be negatively associated with IBD. The FMT group exhibited alleviated colitis, excellent anti-inflammatory effects, improved colonic barrier integrity, and enrichment of bacteria such as Akkermansia (p < 0.05). These results further supported the gut microbiota-dependent mechanism of TS in ameliorating colonic inflammation. CONCLUSION: In conclusion, the TS demonstrated a remission of colitis and amelioration of colonic inflammation in a gut microbiota-dependent manner. The findings suggest that TS could be a potential natural medicine for the protection of UC health. The above results suggest that TS can be used as a potential therapeutic agent for the clinical regulation of UC.
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Colite Ulcerativa , Colite , Doenças Inflamatórias Intestinais , Lactobacillus plantarum , Álcool Feniletílico/análogos & derivados , Simbióticos , Animais , Camundongos , Colite Ulcerativa/tratamento farmacológico , Azeite de Oliva , NF-kappa B , Ocludina , Modelos Animais de Doenças , Colite/induzido quimicamente , Inflamação/complicações , Inflamação/tratamento farmacológico , Colo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BLRESUMO
Despite their low quantity and abundance, the cellulolytic bacteria that inhabit the equine large intestine are vital to their host, as they enable the crucial use of forage-based diets. Fibrobacter succinogenes is one of the most important intestinal cellulolytic bacteria. In this study, Fibrobacter sp. HC4, one cellulolytic strain newly isolated from the horse cecum, was characterized for its ability to utilize plant cell wall fibers. Fibrobacter sp. HC4 consumed only cellulose, cellobiose, and glucose and produced succinate and acetate in equal amounts. Among genes coding for CAZymes, 26% of the detected glycoside hydrolases (GHs) were involved in cellulolysis. These cellulases belong to the GH5, GH8, GH9, GH44, GH45, and GH51 families. Both carboxymethyl cellulase and xylanase activities of Fibrobacter sp. HC4 were detected using the Congo red method and were higher than those of F. succinogenes S85, the type strain. The in vitro addition of Fibrobacter sp. HC4 to a fecal microbial ecosystem of horses with large intestinal acidosis significantly enhanced fibrolytic activity as measured by the increase in gas and volatile fatty acids production during the first 48 h. According to this, the pH decreased and the disappearance of dry matter increased at a faster rate with Fibrobacter sp. HC4. Our data suggest a high specialization of the new strain in cellulose degradation. Such a strain could be of interest for future exploitation of its probiotic potential, which needs to be further determined by in vivo studies.IMPORTANCECellulose is the most abundant of plant cell wall fiber and can only be degraded by the large intestine microbiota, resulting in the production of volatile fatty acids that are essential for the host nutrition and health. Consequently, cellulolytic bacteria are of major importance to herbivores. However, these bacteria are challenged by various factors, such as high starch diets, which acidify the ecosystem and reduce their numbers and activity. This can lead to an imbalance in the gut microbiota and digestive problems such as colic, a major cause of mortality in horses. In this work, we characterized a newly isolated cellulolytic strain, Fibrobacter sp. HC4, from the equine intestinal microbiota. Due to its high cellulolytic capacity, reintroduction of this strain into an equine fecal ecosystem stimulates hay fermentation in vitro. Isolating and describing cellulolytic bacteria is a prerequisite for using them as probiotics to restore intestinal balance.
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BACKGROUND: HIV-infected persons demonstrate notable disturbances in their intestinal microbiota; however, the impact of intestinal microbiota on HIV susceptibility in men who have sex with men (MSM), as well as the effects of HIV and antiretroviral therapy (ART) on their gut microbiota, remains under active study. Thus, our research focuses on clarifying the distinctions in intestinal microbiota composition among uninfected MSM and non-MSM healthy controls, investigating the alterations in early-stage intestinal microbial communities following HIV infection, and assessing how ART affects the intestinal microbiota. METHODS: This study enrolled four participant groups: uninfected MSM, Recent HIV-1 infection (RHI) MSM, MSM on ART, and non-MSM healthy controls, with 30 individuals in each group. We utilized 16S ribosomal DNA (16S rDNA) amplicon sequencing to analyze fecal microbiota and employed Luminex multiplex assays to measure plasma markers for microbial translocation (LBP, sCD14) and the inflammatory marker CRP. FINDINGS: Comparing uninfected MSM to non-MSM healthy controls, no substantial variances were observed in α and ß diversity. Uninfected MSM had higher average relative abundances of Bacteroidetes, Prevotella, and Alloprevotella, while Bacteroides, Firmicutes, and Faecalibacterium had lower average relative abundances. MSM on ART had lower intestinal microbiota diversity than RHI MSM and uninfected MSM. In MSM on ART, Megasphaera and Fusobacterium increased, while Faecalibacterium and Roseburia decreased at genus level. Additionally, treatment with a non-nucleoside reverse transcriptase inhibitor (NNRTI) led to significant alterations in intestinal microbiota diversity and composition compared to RHI MSM. The random forest model showed that HIV infection biomarkers effectively distinguished between newly diagnosed HIV-infected MSM and HIV-negative MSM, with an ROC AUC of 76.24% (95% CI: 61.17-91.31%). CONCLUSIONS: MSM showed early intestinal microbiota imbalances after new HIV infection. MSM on ART experienced worsened dysbiosis, indicating a combined effect of HIV and ART. NNRTI-based treatment notably changed intestinal microbiota, suggesting a potential direct impact of NNRTI drugs on intestinal microbiota.
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Microbioma Gastrointestinal , Infecções por HIV , Homossexualidade Masculina , RNA Ribossômico 16S , Humanos , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Infecções por HIV/microbiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/complicações , Adulto , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/efeitos dos fármacos , Fezes/microbiologia , Fezes/virologia , Pessoa de Meia-Idade , HIV-1/genética , Disbiose/microbiologiaRESUMO
OBJECTIVE: This study aimed to discuss the distinctive features of the intestinal microbiota in neonates with hyperbilirubinemia and to comprehensively analyse the composition of the intestinal microbiota as well as the levels of free amino acids and acylcarnitines in the peripheral blood of neonates experiencing hyperbilirubinemia. RESULTS: At the phylum level, Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Chloroflexi were the five predominant microbial groups identified in both the hyperbilirubinemia and control groups. Alpha diversity analysis, encompassing seven indices, showed no statistically significant differences between the two groups. However, Beta diversity analysis revealed a significant difference in intestinal microbiota structure between the groups. Linear discriminant analysis effect size (LEfSe) indicated a significant reduction in the abundance of Gammaproteobacteria and Enterobacteriaceae within the hyperbilirubinemia group compared to that in the control group. The heatmap revealed that the control group exhibited increased abundances of Escherichia and Bifidobacterium, while the hyperbilirubinemia group exhibited increased levels of Enterococcus and Streptococcus. Regarding blood amino acids and acylcarnitines, there were greater concentrations of citrulline (Cit), arginine (Arg), ornithine (Orn), and valine (Val) in the hyperbilirubinemia group than in the control group. The hyperbilirubinemia group also exhibited significant increases in medium-chain fatty acids (C6, C8), long-chain fatty acids (C18), and free carnitine (C0). CONCLUSION: By comparing neonates with hyperbilirubinemia to those without, a significant disparity in the community structure of the intestinal microbiota was observed. The intestinal microbiota plays a crucial role in the bilirubin metabolism process. The intestinal microbiota of neonates with hyperbilirubinemia exhibited a certain degree of dysbiosis. The abundances of Bacteroides and Bifidobacterium were negatively correlated with the bilirubin concentration. Therefore, the fact that neonates with hyperbilirubinemia exhibit some variations in blood amino acid and acylcarnitine levels may provide, to a certain degree, a theoretical basis for clinical treatment and diagnosis.
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Aminoácidos , Bactérias , Carnitina , Microbioma Gastrointestinal , Humanos , Carnitina/análogos & derivados , Carnitina/sangue , Aminoácidos/sangue , Recém-Nascido , Masculino , Feminino , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , RNA Ribossômico 16S/genéticaRESUMO
BACKGROUND: Colorectal cancer (CRC) is a prevalent malignant malignancy affecting the gastrointestinal tract that is usually treated clinically with chemotherapeutic agents, whereas chemotherapeutic agents can cause severe gastrointestinal toxicity, which brings great pain to patients. Therefore, finding effective adjuvant agents for chemotherapy is crucial. METHODS: In this study, a CRC mouse model was successfully constructed using AOM/DSS, and the treatment was carried out by probiotic Bifidobacterium longum SX-1326 (B. longum SX-1326) in combination with irinotecan. Combining with various techniques of modern biomedical research, such as Hematoxylin and Eosin (H&E), Immunohistochemistry (IHC), Western blotting and 16S rDNA sequencing, we intend to elucidate the effect and mechanism of B. longum SX-1326 in improving the anticancer efficacy and reducing the side effects on the different levels of molecules, animals, and bacteria. RESULTS: Our results showed that B. longum SX-1326 enhanced the expression of Cleaved Caspase-3 (M vs. U = p < 0.01) and down-regulated the expression level of B-cell lymphoma-2 (Bcl-2) through up-regulation of the p53 signaling pathway in CRC mice, which resulted in an adjuvant effect on the treatment of CRC with irinotecan. Moreover, B. longum SX-1326 was also able to regulate the gut-brain-axis (GBA) by restoring damaged enterochromaffin cells, reducing the release of 5-hydroxytryptamine (5-HT) in brain tissue (I vs. U = 89.26 vs. 75.03, p < 0.05), and further alleviating the adverse effects of nausea and vomiting. In addition, B. longum SX-1326 reversed dysbiosis in CRC model mice by increasing the levels of Dehalobacterium, Ruminnococcus, and Mucispirillum. And further alleviated colorectal inflammation by downregulating the TLR4/MyD88/NF-κB signaling pathway. CONCLUSIONS: In conclusion, our work reveals that B. longum SX-1326 has a favorable effect in adjuvant irinotecan for CRC and amelioration of post-chemotherapy side effects, and also provides the theoretical basis and data for finding a safe and efficient chemotherapeutic adjuvant.
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Bifidobacterium longum , Microbioma Gastrointestinal , Animais , Humanos , Camundongos , Eixo Encéfalo-Intestino , Irinotecano/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/farmacologiaRESUMO
BACKGROUND: Hosts, parasites, and microbiota interact with each other, forming a complex ecosystem. Alterations to the microbial structure have been observed in various enteric parasitic infections (e.g. parasitic protists and helminths). Interestingly, some parasites are associated with healthy gut microbiota linked to the intestinal eubiosis state. So the changes in bacteria and metabolites induced by parasite infection may offer benefits to the host, including protection from other parasitesand promotion of intestinal health. The only ciliate known to inhabit the hindgut of grass carp, Balantidium ctenopharyngodoni, does not cause obvious damage to the intestinal mucosa. To date, its impact on intestinal microbiota composition remains unknown. In this study, we investigated the microbial composition in the hindgut of grass carp infected with B. ctenopharyngodoni, as well as the changes of metabolites in intestinal contents resulting from infection. RESULTS: Colonization by B. ctenopharyngodoni was associated with an increase in bacterial diversity, a higher relative abundance of Clostridium, and a lower abundance of Enterobacteriaceae. The family Aeromonadaceae and the genus Citrobacter had significantly lower relative abundance in infected fish. Additionally, grass carp infected with B. ctenopharyngodoni exhibited a significant increase in creatine content in the hindgut. This suggested that the presence of B. ctenopharyngodoni may improve intestinal health through changes in microbiota and metabolites. CONCLUSIONS: We found that grass carp infected with B. ctenopharyngodoni exhibit a healthy microbiota with an increased bacterial diversity. The results suggested that B. ctenopharyngodoni reshaped the composition of hindgut microbiota similarly to other protists with low pathogenicity. The shifts in the microbiota and metabolites during the colonization and proliferation of B. ctenopharyngodoni indicated that it may provide positive effects in the hindgut of grass carp.
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Balantidium , Carpas , Microbioma Gastrointestinal , Animais , Bactérias/genética , VirulênciaRESUMO
OBJECTIVE: The association between heart failure (HF) and intestinal inflammation caused by a disturbed intestinal microbiota in infants with congenital heart disease (CHD) was investigated. METHODS: Twenty infants with HF and CHD who were admitted to our hospital between October 2021 and March 2022 were included in this study. Twenty age- and sex-matched infants without HF at our hospital were selected as the control group. Faecal samples were obtained from each participant and analysed by enzyme-linked immunoassay and 16 S rDNA sequencing to assess intestinal inflammatory factors and the microbiota. RESULTS: The levels of intestinal inflammatory factors, including IL-1ß, IL-4, IL-6, IL-17 A and TNF-α, were greatly increased, while the levels of IL-10 were significantly decreased in the HF group compared to the control group (p < 0.05). The intestinal microbial diversity of patients in the HF group was markedly lower than that in the control group (p < 0.05). The abundance of Enterococcus was significantly increased in the HF group compared to the control group (p < 0.05), but the abundance of Bifidobacterium was significantly decreased in the HF group compared to the control group (p < 0.05). The diversity of the intestinal microbiota was negatively correlated with the levels of IL-1ß, IL-4, IL-6 and TNF-α in the intestinal tract but was positively correlated with that of IL-10. The abundance of Enterococcus was positively associated with the levels of IL-1ß, IL-4, IL-6 and TNF-α in the intestinal tract but was negatively correlated with that of IL-10. NT-proBNP was positively associated with the levels of IL-1ß, IL-4, IL-6 and TNF-α in the HF group but was negatively correlated with that of IL-10. The heart function score was positively associated with the levels of IL-1ß, IL-4, IL-6 and TNF-α in the HF group but was negatively correlated with that of IL-10. CONCLUSIONS: Infants with CHD-related HF had a disordered intestinal microbiota, decreased diversity of intestinal microbes, increased levels of pathogenic bacteria and decreased levels of beneficial bacteria. The increased abundance of Enterococcus and the significant decrease in the diversity of the intestinal microbiota may exacerbate the intestinal inflammatory response, which may be associated with the progression of HF.
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Cardiopatias Congênitas , Insuficiência Cardíaca , Lactente , Humanos , Interleucina-10 , Fator de Necrose Tumoral alfa , Interleucina-6 , Interleucina-4 , Insuficiência Cardíaca/complicações , Cardiopatias Congênitas/complicações , Enterococcus/genética , InflamaçãoRESUMO
BACKGROUND: Bacteroides fragilis group (BFG) species are the most significant anaerobic pathogens and are also the most antibiotic-resistant anaerobic species. Therefore, surveying their antimicrobial resistance levels and investigating their antibiotic resistance mechanisms is recommended. Since their infections are endogenous and they are important constituents of the intestinal microbiota, the properties of the intestinal strains are also important to follow. The aim of this study was to investigate the main antibiotic gene content of microbiota isolates from healthy people and compare them with the gene carriage of strains isolated from infections. RESULTS: We detected 13, mainly antibiotic resistance determinants of 184 intestinal BFG strains that were isolated in 5 European countries (Belgium, Germany, Hungary, Slovenia and Turkey) and compared these with values obtained earlier for European clinical strains. Differences were found between the values of this study and an earlier one for antibiotic resistance genes that are considered to be mobile, with higher degrees for cfxA, erm(F) and tet(Q) and with lower degrees for msrSA, erm(B) and erm(G). In addition, a different gene prevalence was found depending on the taxonomical groups, e.g., B. fragilis and NBFB. Some strains with both the cepA and cfiA ß-lactamase genes were also detected, which is thought to be exceptional since until now, the B. fragilis genetic divisions were defined by the mutual exclusion of these two genes. CONCLUSIONS: Our study detected the prevalences of a series of antibiotic resistance genes in intestinal Bacteroides strains which is a novelty. In addition, based on the current and some previous data we hypothesized that prevalence of some antibiotic resistance genes detected in the clinical and intestinal BFG strains were different, which could be accounted with the differential composition of the Bacteroides microbiota and/or the MGE mobilities at the luminal vs. mucosal sites of the intestine.
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Antibacterianos , Infecções por Bacteroides , Bacteroides , Carbapenêmicos , Humanos , Europa (Continente) , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Bacteroides/microbiologia , Bacteroides/genética , Bacteroides/efeitos dos fármacos , Bacteroides/isolamento & purificação , Farmacorresistência Bacteriana/genética , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Testes de Sensibilidade Microbiana , Genes Bacterianos/genética , Intestinos/microbiologia , Proteínas de Bactérias/genéticaRESUMO
Diarrhea in calves is a common disease that results in poor nutrient absorption, poor growth and early death which leads to productivity and economic losses. Therefore, it is important to explore the methods to reduce diarrhea in yak's calves. Efficacy of lactic acid bacteria (LAB) for improvement of bacterial diarrhea is well recognized. For this purpose, two different doses (107 CFU, 1011 CFU) of Lactobacillus yoelii FYL1 isolated from yaks were fed to juvenile yaks exposed to E. coli O78. After a trial period of ten days fresh feces and intestinal contents of the experimental yaks were collected and metagenomics sequencing was performed. It was found that feeding a high dose of Lactobacillus yoelii FYL1 decreased abundance of phylum Firmicutes in the E. coli O78 infected group whereas, it was high in animals fed low dose of Lactobacillu yoelii FYL1. Results also revealed that counts of bacteria from the family Oscillospiraceae, genus Synergistes and Megasphaera were higher in control group whereas, order Bifidobacteriales and family Bifidobacteriaceae were higher in infected group. It was observed that bacterial counts for Pseudoruminococcus were significantly (P < 0.05) higher in animals of group that were given high dose of Lactobacillus yoelii FYL1 (HLAB). Compared to infected group multiple beneficial bacterial genera such as Deinococus and Clostridium were found higher in the animals that were given a low dose of Lactobacillus yoelii FYL1 (LLAB). The abundance of pathogenic bacterial genera that included Parascardovia, Bacteroides and Methanobrevibacter was decreased (P < 0.05) in the lower dose treated group. The results of functional analysis revealed that animals of LLAB had a higher metabolism of terpenoids and polyketides compared to animals of infected group. Virus annotation also presented a significant inhibitory effect of LLAB on some viruses (P < 0.05). It was concluded that L. yoelii FYL1 had an improved effect on gut microbiota of young yaks infected with E. coli O78. This experiment contributes to establish the positive effects of LAB supplementation while treating diarrhea.
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Infecções Bacterianas , Disenteria , Microbioma Gastrointestinal , Bovinos , Animais , Lactobacillus , Escherichia coli , Diarreia/veterinária , Diarreia/microbiologia , BactériasRESUMO
Background: According to recent studies, atherosclerosis and gut microbiota are related. Nevertheless, it has been discovered that the gut microbiota varies across studies, with its function still being debated, and such relationships not proven to be causal. Thus, our study aimed to identify the key gut microbiota taxa (GM taxa) at different taxonomic levels, namely, the phylum, class, order, family, and genus, to investigate any potential causal links to atherosclerosis. Methods: We employed summary data from the MiBioGen consortium on the gut microbiota to conduct a sophisticated two-sample Mendelian randomization (MR) analysis. Pertinent information regarding atherosclerosis statistics was acquired from the FinnGen Consortium R8 publication. To assess causality, the utilized principal analytical technique was the inverse variance-weighted (IVW) method. Supplementary to IVW, additional MR methodologies were employed, including weighted median, MR-Egger, weighted methods, and simple mode. Sensitivity analyses involved the application of Cochrane's Q-test, MR-Egger intercept test, MR-PRESSO global test, and leave-one-out analysis. Results: Finally, after performing an MR study on the risk of 211 GM taxa on atherosclerosis, we discovered 20 nominal links and one strong causal link. Firmicutes (phylum ID: 1672) (odds ratio (OR) = 0.852 (0.763, 0.950), p = 0.004) continued to be connected with a lower incidence of coronary atherosclerosis, even after Bonferroni correction. Conclusions: Based on the discovered data, it was established that the phylum Firmicutes exhibits a causal relationship with a reduced occurrence of coronary atherosclerosis. This investigation could potentially provide novel insights into therapeutic objectives for atherosclerosis by focusing on the gut microbiota.
RESUMO
Constipation is a common gastrointestinal condition, which may occur at any age and affects countless people. The search for new treatments for constipation is ongoing as current drug treatments fail to provide fully satisfactory results. In recent years, probiotics have attracted much attention because of their demonstrated therapeutic efficacy and fewer side effects than pharmaceutical products. Many studies attempted to answer the question of how probiotics can alleviate constipation. It has been shown that different probiotic strains can alleviate constipation by different mechanisms. The mechanisms on probiotics in relieving constipation were associated with various aspects, including regulation of the gut microbiota composition, the level of short-chain fatty acids, aquaporin expression levels, neurotransmitters and hormone levels, inflammation, the intestinal environmental metabolic status, neurotrophic factor levels and the body's antioxidant levels. This paper summarizes the perception of the mechanisms on probiotics in relieving constipation and provides some suggestions on new research directions.
RESUMO
Lactobacillus species is one of the most commonly used probiotics with a wide range of health-promoting effects, and beneficial effects of the surface protein of the lactobacillus could potentially be involved in the action of probiotics in the gastrointestinal tract. In this study, the anti-inflammatory effect of LPxTG-motif surface protein (LMP) derived from Limosilactobacillus reuteri SH 23 was assessed using a mouse model of colitis induced by dextran sodium sulfate (DSS). The results showed that LMP has the inhibition properties upon the DSS-induced ulcerative colitis of mice via the MAPK-dependent NF-κB pathway. The inflammatory factors TNF-α and IL-6 were inhibited, and the IL-10 secretion was enhanced in the LMP-treated DSS mice model. Furthermore, the diversity of the intestinal microbiota bacteria in this treated group was also influenced, including the increase in the abundance of Lactobacillus and Akkermansia genus in the LMP-treated mice groups, and there is a positive correlation between the IL-10 cytokines with the changes in the intestinal microbiota Lactobacillus and Akkermansia. Therefore, LMP derived from the Limosilactobacillus reuteri SH 23 has the potential to alleviate inflammatory diseases through the balance of the intestinal flora with the inhibition of the inflammatory factors in the NF-κB pathway.