Východiska: Incidence karcinomu pankreatu (pancreatic ductal adenocarcinoma – PDAC) má zejména v rozvinutých zemích zvyšující se tendenci. V roce 2021 bylo celosvětově diagnostikováno 496 000 nových případů PDAC. Incidence v ČR je jedna z nejvyšších na světě a za rok 2018 bylo zachyceno 2 332 nových pacientů. Vzhledem k absenci symptomů v časných stadiích je přibližně 50 % pacientů vstupně diagnostikováno se vzdálenými metastázemi. Mortalita je nepatrně nižší než incidence a navzdory výrazným pokrokům v onkologickém výzkumu zůstává PDAC stále fatální diagnózou. Zajímavým přístupem, a to nejen u PDAC, je studium mikrobiomu. Ten je definován jako soubor všech mikroorganizmů (mikrobiota, tedy bakterie, houby, viry archea a protozoa) a jejich genomu v určitém prostředí. Za fyziologických podmínek je střevní mikrobiom v symbióze s osídleným organizmem, a udržuje tak rovnováhu metabolizmu, slizniční imunomodulaci a reguluje proces trávení. Při dysregulaci počtu či funkce střevních mikroorganizmů nastává dysbióza. Ta pak vede ke vzniku metabolických a kardiovaskulárních chorob, k poruchám nervového systému, indukci zánětů střeva či kancerogenezi. Mikrobiota mohou indukovat kancerogenezi několika způsoby, a to zejména vyvoláním zánětlivé odpovědi, snížením schopnosti imunitního systému eliminovat poškozené buňky a v neposlední řadě mohou metabolity mikrobů vést k deregulaci genomu osídleného organizmu. Tato deregulace vede k aktivaci proapoptotických a proproliferativních proteinů. Dosavadní výzkum prokazuje, že na rozvoji PDAC se může podílet právě střevní či orální mikrobiom. Jednou z nejvíce studovaných bakterií je Porphyromonas gingivalis. I u dalších bakterií, jako jsou Fusobacteria, Enterobacter, Klebsiella, Prevotella či Rothia, byla prokázána role při vzniku PDAC. Cíl: Cílem tohoto přehledového článku je poukázat na jeden z možných mechanizmů vzniku PDAC. Ten by mohl být ovlivnitelný, což může znamenat snížení incidence a zlepšení prognózy tohoto agresivního onemocnění.
Background: The incidence of pancreatic cancer (pancreatic ductal adenocarcinoma – PDAC) is increasing, especially in developed countries. In 2021, 496,000 new PDAC cases were diagnosed worldwide. In the Czech Republic, the incidence is one of the highest in the world, with 2,332 new PDAC patients diagnosed in 2018. Due to the absence of symptoms in the early stages, approximately 50% of patients are initially diagnosed with distant metastases. Mortality is slightly lower than the incidence count and, despite significant advances in cancer research, PDAC remains a fatal diagnosis. However, microbiome seems to be an interesting approach, and not only in PDAC patients. Microbiome is defined as the set of all microorganisms (microbiota, i.e. bacteria, fungi, viruses, archaea, and protozoa) and their genome in a certain environment. In a physiological setting, the gut microbiome is in symbiosis with the host organism, maintaining the balance of metabolism, mucosal immunomodulation and regulating the digestion process. When dysregulation of the number or function of intestinal microorganisms occurs, dysbiosis is developed. It may lead to metabolic and cardiovascular diseases, nervous system disorders, induction of intestinal inflammation, or carcinogenesis. Microbiota can induce carcinogenesis in multiple ways, such as by activating an inflammatory response, reducing the immune system‘s ability to eliminate damaged cells, and deregulation of the host genome by microbial metabolites. This deregulation may lead to an activation of pro-apoptotic and pro-proliferative proteins. To date, research shows that the gut or oral microbiome may be involved in the development of PDAC. One of the most studied bacteria is Porphyromonas gingivalis. Other bacteria, such as Fusobacteria, Enterobacter, Klebsiella, Prevotella, and Rothia, have also been shown to play a role in PDAC. Purpose: The aim of this review article is to point out one of the possible mechanisms of cancerogenesis in PDAC patients and its therapeutic influence to reduce the incidence and improve the prognosis of this aggressive disease.
- MeSH
- duktální karcinom pankreatu * diagnóza epidemiologie etiologie mikrobiologie MeSH
- dysbióza komplikace mikrobiologie patologie MeSH
- karcinogeneze patologie MeSH
- lidé MeSH
- mikrobiota * MeSH
- rizikové faktory MeSH
- střevní mikroflóra genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
BACKGROUND: Individuals that band together create new ecological opportunities for microorganisms. In vertical transmission, theory predicts a conserved microbiota within lineages, especially social bees. Bees exhibit solitary to social behavior among and/or within species, while life cycles can be annual or perennial. Bee nests may be used over generations or only once, and foraging ecology varies widely. To assess which traits are associated with bee microbiomes, we analyzed microbial diversity within solitary and social bees of Apidae, Colletidae, and Halictidae, three bee families in Panama's tropical forests. Our analysis considered the microbiome of adult gut contents replicated through time, localities, and seasons (wet and dry) and included bee morphology and comparison to abdominal (dissected) microbiota. Diversity and distribution of tropical bee microbes (TBM) within the corbiculate bee clade were emphasized. RESULTS: We found the eusocial corbiculate bees tended to possess a more conserved gut microbiome, attributable to vertical transmission, but microbial composition varied among closely related species. Euglossine bees (or orchid bees), corbiculates with mainly solitary behavior, had more variable gut microbiomes. Their shorter-tongued and highly seasonal species displayed greater diversity, attributable to flower-visiting habits. Surprisingly, many stingless bees, the oldest corbiculate clade, lacked bacterial genera thought to predate eusociality, while several facultatively social, and solitary bee species possessed those bacterial taxa. Indeed, nearly all bee species displayed a range of affinities for single or multiple variants of the "socially associated" bacterial taxa, which unexpectedly demonstrated high sequence variation. CONCLUSIONS: Taken together, these results call into question whether specific bacterial associates facilitate eusocial behavior, or are subsequently adopted, or indicate frequent horizontal transmission between perennial eusocial colonies and other social, facultatively social, and solitary bees. Video Abstract.
- MeSH
- lesy MeSH
- mikrobiota * genetika MeSH
- sociální chování MeSH
- střevní mikroflóra * genetika MeSH
- včely MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
Blastocystis is the most prevalent microbial eukaryote in the human and animal gut, yet its role as commensal or parasite is still under debate. Blastocystis has clearly undergone evolutionary adaptation to the gut environment and possesses minimal cellular compartmentalization, reduced anaerobic mitochondria, no flagella, and no reported peroxisomes. To address this poorly understood evolutionary transition, we have taken a multi-disciplinary approach to characterize Proteromonas lacertae, the closest canonical stramenopile relative of Blastocystis. Genomic data reveal an abundance of unique genes in P. lacertae but also reductive evolution of the genomic complement in Blastocystis. Comparative genomic analysis sheds light on flagellar evolution, including 37 new candidate components implicated with mastigonemes, the stramenopile morphological hallmark. The P. lacertae membrane-trafficking system (MTS) complement is only slightly more canonical than that of Blastocystis, but notably, we identified that both organisms encode the complete enigmatic endocytic TSET complex, a first for the entire stramenopile lineage. Investigation also details the modulation of mitochondrial composition and metabolism in both P. lacertae and Blastocystis. Unexpectedly, we identify in P. lacertae the most reduced peroxisome-derived organelle reported to date, which leads us to speculate on a mechanism of constraint guiding the dynamics of peroxisome-mitochondrion reductive evolution on the path to anaerobiosis. Overall, these analyses provide a launching point to investigate organellar evolution and reveal in detail the evolutionary path that Blastocystis has taken from a canonical flagellated protist to the hyper-divergent and hyper-prevalent animal and human gut microbe.
- MeSH
- Blastocystis * genetika MeSH
- Eukaryota MeSH
- lidé MeSH
- mitochondrie genetika metabolismus MeSH
- organely metabolismus MeSH
- střevní mikroflóra * genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND AND AIMS: The gut microbiota is implicated in the pathogenesis of colorectal cancer (CRC). We aimed to map the CRC mucosal microbiota and metabolome and define the influence of the tumoral microbiota on oncological outcomes. METHODS: A multicentre, prospective observational study was conducted of CRC patients undergoing primary surgical resection in the UK (n = 74) and Czech Republic (n = 61). Analysis was performed using metataxonomics, ultra-performance liquid chromatography-mass spectrometry (UPLC-MS), targeted bacterial qPCR and tumour exome sequencing. Hierarchical clustering accounting for clinical and oncological covariates was performed to identify clusters of bacteria and metabolites linked to CRC. Cox proportional hazards regression was used to ascertain clusters associated with disease-free survival over median follow-up of 50 months. RESULTS: Thirteen mucosal microbiota clusters were identified, of which five were significantly different between tumour and paired normal mucosa. Cluster 7, containing the pathobionts Fusobacterium nucleatum and Granulicatella adiacens, was strongly associated with CRC (PFDR = 0.0002). Additionally, tumoral dominance of cluster 7 independently predicted favourable disease-free survival (adjusted p = 0.031). Cluster 1, containing Faecalibacterium prausnitzii and Ruminococcus gnavus, was negatively associated with cancer (PFDR = 0.0009), and abundance was independently predictive of worse disease-free survival (adjusted p = 0.0009). UPLC-MS analysis revealed two major metabolic (Met) clusters. Met 1, composed of medium chain (MCFA), long-chain (LCFA) and very long-chain (VLCFA) fatty acid species, ceramides and lysophospholipids, was negatively associated with CRC (PFDR = 2.61 × 10-11); Met 2, composed of phosphatidylcholine species, nucleosides and amino acids, was strongly associated with CRC (PFDR = 1.30 × 10-12), but metabolite clusters were not associated with disease-free survival (p = 0.358). An association was identified between Met 1 and DNA mismatch-repair deficiency (p = 0.005). FBXW7 mutations were only found in cancers predominant in microbiota cluster 7. CONCLUSIONS: Networks of pathobionts in the tumour mucosal niche are associated with tumour mutation and metabolic subtypes and predict favourable outcome following CRC resection. Video Abstract.
- MeSH
- chromatografie kapalinová MeSH
- kolorektální nádory * chirurgie MeSH
- lidé MeSH
- mikrobiota * genetika MeSH
- střevní mikroflóra * genetika MeSH
- tandemová hmotnostní spektrometrie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- pozorovací studie MeSH
- práce podpořená grantem MeSH
BACKGROUND: Mechanistic data indicate the benefit of short-chain fatty acids (SCFA) produced by gut microbial fermentation of fiber on colorectal cancer, but direct epidemiologic evidence is limited. A recent study identified SNPs for two SCFA traits (fecal propionate and butyrate-producing microbiome pathway PWY-5022) in Europeans and showed metabolic benefits. METHODS: We conducted a two-sample Mendelian randomization analysis of the genetic instruments for the two SCFA traits (three SNPs for fecal propionate and nine for PWY-5022) in relation to colorectal cancer risk in three large European genetic consortia of 58,131 colorectal cancer cases and 67,347 controls. We estimated the risk of overall colorectal cancer and conducted subgroup analyses by sex, age, and anatomic subsites of colorectal cancer. RESULTS: We did not observe strong evidence for an association of the genetic predictors for fecal propionate levels and the abundance of PWY-5022 with the risk of overall colorectal cancer, colorectal cancer by sex, or early-onset colorectal cancer (diagnosed at <50 years), with no evidence of heterogeneity or pleiotropy. When assessed by tumor subsites, we found weak evidence for an association between PWY-5022 and risk of rectal cancer (OR per 1-SD, 0.95; 95% confidence intervals, 0.91-0.99; P = 0.03) but it did not surpass multiple testing of subgroup analysis. CONCLUSIONS: Genetic instruments for fecal propionate levels and the abundance of PWY-5022 were not associated with colorectal cancer risk. IMPACT: Fecal propionate and PWY-5022 may not have a substantial influence on colorectal cancer risk. Future research is warranted to comprehensively investigate the effects of SCFA-producing bacteria and SCFAs on colorectal cancer risk.
- MeSH
- butyráty * analýza metabolismus MeSH
- feces * chemie mikrobiologie MeSH
- kolorektální nádory * epidemiologie genetika metabolismus MeSH
- kyseliny mastné těkavé analýza genetika metabolismus MeSH
- lidé MeSH
- mendelovská randomizace MeSH
- propionáty * analýza metabolismus MeSH
- riziko MeSH
- střevní mikroflóra * genetika fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Evropa MeSH
The human microbiome influences the efficacy and safety of a wide variety of commonly prescribed drugs. Designing precision medicine approaches that incorporate microbial metabolism would require strain- and molecule-resolved, scalable computational modeling. Here, we extend our previous resource of genome-scale metabolic reconstructions of human gut microorganisms with a greatly expanded version. AGORA2 (assembly of gut organisms through reconstruction and analysis, version 2) accounts for 7,302 strains, includes strain-resolved drug degradation and biotransformation capabilities for 98 drugs, and was extensively curated based on comparative genomics and literature searches. The microbial reconstructions performed very well against three independently assembled experimental datasets with an accuracy of 0.72 to 0.84, surpassing other reconstruction resources and predicted known microbial drug transformations with an accuracy of 0.81. We demonstrate that AGORA2 enables personalized, strain-resolved modeling by predicting the drug conversion potential of the gut microbiomes from 616 patients with colorectal cancer and controls, which greatly varied between individuals and correlated with age, sex, body mass index and disease stages. AGORA2 serves as a knowledge base for the human microbiome and paves the way to personalized, predictive analysis of host-microbiome metabolic interactions.
Animal models are essential in understanding of the mechanisms of sepsis moreover the development and the assessment of emerging therapies. In clinically relevant porcine model, however, a significant variability in the host response has been observed among animals. Thus, there is a strong demand to better understand the potential sources of this heterogeneity. In this study, we compared faecal microbiome composition of 12 animals. Three samples were collected at different time points from each animal. Bacteriome was subjected to 16S rDNA profiling. A significant difference in bacterial composition was associated with the season (p < 0.001) but not with the sex of the pig (p = 0.28), the timing of sample collection (p = 0.59), or interactions thereof (all p > 0.3). The season batch explained 55% of the total variance in the bacteriome diversity. The season term was highly significant from the high-resolution level of the bacterial amplicon sequencing variants up to the level of phylum. The diversity of the microbiome composition could significantly influence experimental model of sepsis, and studies are warranted to demonstrate the effects of gut microbiome diversity on the host-response. If confirmed, control of the gut microbiome should become a standard part of the pre-clinical sepsis experiments.
The human microbiome influences human health in both negative and positive ways. Studies on the transportomes of these organisms yield information that may be utilized for various purposes, including the identification of novel drug targets and the manufacture of improved probiotic strains. Moreover, these genomic analyses help to improve our understanding of the physiology and metabolic capabilities of these organisms. The present study is a continuation of our studies on the transport proteins of the major gut microbes. Bifidobacterium species are essential members of the human gut microbiome, and they initiate colonization of the gut at birth, providing health benefits that last a lifetime. In this study we analyze the transportomes of nine bifidobacterial species: B. adolescentis, B. animalis, B. bifidum, B. breve, B. catenulatum, B. dentium, B. longum subsp. infantis, B. longum subsp. longum, and B. pseudocatenulatum. All of these species have proven probiotic characteristics and exert beneficial effects on human health. Surprisingly, we found that all nine of these species have similar pore-forming toxins and drug exporters that may play roles in pathogenesis. These species have transporters for amino acids, carbohydrates, and proteins, essential for their organismal lifestyles and adaption to their respective ecological niches. The strictly probiotic species, B. bifidum, however, contains fewer such transporters, thus indicative of limited interactions with host cells and other gut microbial counterparts. The results of this study were compared with those of our previous studies on the transportomes of multiple species of Bacteroides, Escherichia coli/Salmonella, and Lactobacillus. Overall, bifidobacteria have larger transportomes (based on percentages of total proteins) than the previously examined groups of bacterial species, with a preference for primary active transport systems over secondary carriers. Taken together, these results provide useful information about the physiologies and pathogenic potentials of these probiotic organisms as reflected by their transportomes.
- MeSH
- Bifidobacterium bifidum * MeSH
- Bifidobacterium genetika MeSH
- lidé MeSH
- novorozenec MeSH
- probiotika * MeSH
- střevní mikroflóra * genetika MeSH
- transportní proteiny metabolismus MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Extramural MeSH
- srovnávací studie MeSH
BACKGROUND: Termites primarily feed on lignocellulose or soil in association with specific gut microbes. The functioning of the termite gut microbiota is partly understood in a handful of wood-feeding pest species but remains largely unknown in other taxa. We intend to fill this gap and provide a global understanding of the functional evolution of termite gut microbiota. RESULTS: We sequenced the gut metagenomes of 145 samples representative of the termite diversity. We show that the prokaryotic fraction of the gut microbiota of all termites possesses similar genes for carbohydrate and nitrogen metabolisms, in proportions varying with termite phylogenetic position and diet. The presence of a conserved set of gut prokaryotic genes implies that essential nutritional functions were present in the ancestor of modern termites. Furthermore, the abundance of these genes largely correlated with the host phylogeny. Finally, we found that the adaptation to a diet of soil by some termite lineages was accompanied by a change in the stoichiometry of genes involved in important nutritional functions rather than by the acquisition of new genes and pathways. CONCLUSIONS: Our results reveal that the composition and function of termite gut prokaryotic communities have been remarkably conserved since termites first appeared ~ 150 million years ago. Therefore, the "world's smallest bioreactor" has been operating as a multipartite symbiosis composed of termites, archaea, bacteria, and cellulolytic flagellates since its inception. Video Abstract.
- MeSH
- fylogeneze MeSH
- Isoptera * MeSH
- metagenom MeSH
- půda MeSH
- střevní mikroflóra * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- práce podpořená grantem MeSH
The physiology of males and females can be vastly different, complicating interpretation of toxicological and physiological data. The objectives of this study were to elucidate the sex differences in the microbiome-gastrointestinal (GI) transcriptome of adult zebrafish. We compared microbial composition and diversity in both males and females fed the same diet and housed in the same environment. There were no sex-specific differences in weight gain nor gastrointestinal morphology based on histopathology. There was no difference in gut microbial diversity, richness (Shannon and Chao1 index) nor predicted functional composition of the microbiome between males and females. Prior to post-hoc correction, male zebrafish showed higher abundance for the bacterial families Erythrobacteraceae and Lamiaceae, both belonging to the phyla Actinobacteria and Proteobacteria. At the genus level, Lamia and Altererythrobacter were more dominant in males and an unidentified genus in Bacteroidetes was more abundant in females. There were 16 unique differentially expressed transcripts in the gastrointestinal tissue between male and female zebrafish (FDR corrected, p < 0.05). Relative to males, the mRNA expression for trim35-9, slc25a48, chchd3b, csad, and hsd17b3 were lower in female GI while cyp2k6, adra2c, and bckdk were higher in the female GI. Immune and lipid-related gene network expression differed between the sexes (i.e., cholesterol export and metabolism) as well as networks related to gastric motility, gastrointestinal system absorption and digestion. Such data provide clues as to putative differences in gastrointestinal physiology between male and female zebrafish. This study identifies host-transcriptome differences that can be considered when interpreting the microgenderome of zebrafish in studies investigating GI physiology and toxicology of fishes.
