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Nature Medicine Feb 2021The gut microbiome is shaped by diet and influences host metabolism; however, these links are complex and can be unique to each individual. We performed deep metagenomic... (Clinical Trial)
Clinical Trial
The gut microbiome is shaped by diet and influences host metabolism; however, these links are complex and can be unique to each individual. We performed deep metagenomic sequencing of 1,203 gut microbiomes from 1,098 individuals enrolled in the Personalised Responses to Dietary Composition Trial (PREDICT 1) study, whose detailed long-term diet information, as well as hundreds of fasting and same-meal postprandial cardiometabolic blood marker measurements were available. We found many significant associations between microbes and specific nutrients, foods, food groups and general dietary indices, which were driven especially by the presence and diversity of healthy and plant-based foods. Microbial biomarkers of obesity were reproducible across external publicly available cohorts and in agreement with circulating blood metabolites that are indicators of cardiovascular disease risk. While some microbes, such as Prevotella copri and Blastocystis spp., were indicators of favorable postprandial glucose metabolism, overall microbiome composition was predictive for a large panel of cardiometabolic blood markers including fasting and postprandial glycemic, lipemic and inflammatory indices. The panel of intestinal species associated with healthy dietary habits overlapped with those associated with favorable cardiometabolic and postprandial markers, indicating that our large-scale resource can potentially stratify the gut microbiome into generalizable health levels in individuals without clinically manifest disease.
Topics: Adult; Biomarkers; Blastocystis; Blood Glucose; Child; Diet; Fasting; Feeding Behavior; Female; Food Microbiology; Gastrointestinal Microbiome; Glucose; High-Throughput Nucleotide Sequencing; Humans; Male; Metagenome; Microbiota; Middle Aged; Obesity; Postprandial Period; Prevotella
PubMed: 33432175
DOI: 10.1038/s41591-020-01183-8 -
Frontiers in Immunology 2022The physical barrier of the intestine and associated mucosal immunity maintains a delicate homeostatic balance between the host and the external environment by... (Review)
Review
The physical barrier of the intestine and associated mucosal immunity maintains a delicate homeostatic balance between the host and the external environment by regulating immune responses to commensals, as well as functioning as the first line of defense against pathogenic microorganisms. Understanding the orchestration and characteristics of the intestinal mucosal immune response during commensal or pathological conditions may provide novel insights into the mechanisms underlying microbe-induced immunological tolerance, protection, and/or pathogenesis. Over the last decade, our knowledge about the interface between the host intestinal mucosa and the gut microbiome has been dominated by studies focused on bacterial communities, helminth parasites, and intestinal viruses. In contrast, specifically how commensal and pathogenic protozoa regulate intestinal immunity is less well studied. In this review, we provide an overview of mucosal immune responses induced by intestinal protozoa, with a major focus on the role of different cell types and immune mediators triggered by commensal ( spp. and spp.) and pathogenic (, , ) protozoa. We will discuss how these various protozoa modulate innate and adaptive immune responses induced in experimental models of infection that benefit or harm the host.
Topics: Cryptosporidiosis; Cryptosporidium; Humans; Immunity, Mucosal; Intestinal Mucosa; Intestines
PubMed: 36211380
DOI: 10.3389/fimmu.2022.963723 -
Parasites & Vectors Jul 2020Diarrheal diseases caused by intestinal protozoan parasites are a major food-borne public health problem across the world. Vegetables and fruits provide important... (Review)
Review
Diarrheal diseases caused by intestinal protozoan parasites are a major food-borne public health problem across the world. Vegetables and fruits provide important nutrients and minerals, but are also common sources of some food-borne human pathogenic microorganisms. The contamination of raw vegetables and fruits with human pathogenic parasites are now a global public health threat, despite the health benefits of these foods in non-pharmacological prophylaxes against diseases. A large number of reports have documented the contamination of vegetables or fruits with human pathogenic microorganisms. In this paper, we reviewed the contamination and detection methods of human pathogenic intestinal protozoans that are frequently recovered from raw vegetables and fruits. The protozoan parasites include Cryptosporidium spp., Giardia duodenalis, Cyclospora cayetanensis, Entamoeba spp., Toxoplasma gondii, Balantioides coli, Blastocystis sp., Cystoisospora belli and Enterocytozoon bieneusi. The risk factors involved in the contamination of vegetables and fruits with parasites are also assessed.
Topics: Animals; Blastocystis; Cryptosporidium; Cyclospora; Entamoeba; Enterocytozoon; Food Parasitology; Fruit; Giardia lamblia; Global Health; Humans; Intestinal Diseases, Parasitic; Parasites; Risk Factors; Toxoplasma; Vegetables
PubMed: 32727529
DOI: 10.1186/s13071-020-04255-3 -
Microorganisms Jan 2022is a unicellular eukaryote found in the gastrointestinal tract of both human and other animal hosts. The clinical significance of colonic colonization remains obscure....
is a unicellular eukaryote found in the gastrointestinal tract of both human and other animal hosts. The clinical significance of colonic colonization remains obscure. In this study, we used metabarcoding and bioinformatics analyses to identify differences in stool microbiota diversity between -positive and -negative individuals (n = 1285). Alpha diversity was significantly higher in carriers. At phylum level, Firmicutes and Bacteroidetes were enriched in carriers, while Proteobacteria were enriched in non-carriers. The genera , , , , , and were enriched in carriers, whereas , , , and were enriched in non-carriers. No difference in beta diversity was observed. Individuals with -positive stools appear to have gut microbiomes associated with eubiosis unlike those with -negative stools, whose gut microbiomes are similar to those associated with dysbiosis. The role of as an indicator organism and potential modulator of the gut microbiota warrants further scrutiny.
PubMed: 35208781
DOI: 10.3390/microorganisms10020326 -
Turkiye Parazitolojii Dergisi Sep 2023is an anaerobic protozoan with global importance because of infecting a variety of hosts and having high prevalence in many countries. isolates display remarkable... (Review)
Review
is an anaerobic protozoan with global importance because of infecting a variety of hosts and having high prevalence in many countries. isolates display remarkable genetic differences, and many subtypes (STs) have currently been defined based on polymorphism in coding gene. Each 25 subtype may have different characteristics such as pathogenicity, host specificity, and structural variations. Most current research on has focused on these differences and molecular epidemiology. This review aimed to provide a summary of subtype distribution in Türkiye. Regarding human samples, 16 manuscripts were found in the literature, which presented 783 isolates from 9 cities in Türkiye. The most common subtype was ST3 (47.9%), the others were ST1 30 (17.5%), ST2 (14.7%), ST4 (4%), and ST5-ST7 (15.9%). There were few studies on animal hosts and environmental samples. The faecal samples from rats, farm, and pet animals were examined for subtypes and ST1, ST3, ST4-ST7, ST10, and ST12-ST14 were reported. In addition, two studies reported ST1 and ST3 subtypes in environmental water samples. In conclusion, the review of available literature showed that a systematic understanding of the subtype distribution of 35 in Türkiye is still lacking. Most of the studies were performed in a limited number of cities, animal hosts, and environmental samples, therefore, more studies from different provinces are needed in forthcoming research. The majority studies were performed in a limited number of provinces, animal species and very few environmental samples, so in the future; there is a need of novel studies that evaluate more samples from different provinces.
Topics: Humans; Animals; Rats; Blastocystis; Cities; Feces; Polymorphism, Genetic
PubMed: 37724369
DOI: 10.4274/tpd.galenos.2023.79188 -
Parasites & Vectors Oct 2020Blastocystis is a protist that lives in the intestinal tract of a variety of hosts, including humans. It is still unclear how Blastocystis causes disease, which presents...
BACKGROUND
Blastocystis is a protist that lives in the intestinal tract of a variety of hosts, including humans. It is still unclear how Blastocystis causes disease, which presents an ongoing challenge for researchers. Despite the controversial findings on the association between Blastocystis and clinical digestive manifestations, there is currently no consensus as to whether this protozoan actually behaves as a pathogen in humans. Furthermore, the relationship between Blastocystis and the intestinal microbiota composition is not yet clear. For that reason, the aim of this study was to identify if colonization by Blastocystis is related to changes in the diversity and relative abundance of bacterial communities, compared with those of Blastocystis-free individuals in a group of Colombian children.
METHODS
We took stool samples from 57 school-aged children attending a daycare institution in Popayán (Southwest Colombia). Whole DNA was extracted and examined by 16S-rRNA amplicon-based sequencing. Blastocystis was detected by real time PCR and other intestinal parasites were detected by microscopy. We evaluated if Blastocystis was associated with host variables and the diversity and abundance of microbial communities.
RESULTS
The composition of the intestinal bacterial community was not significantly different between Blastocystis-free and Blastocystis-colonized children. Despite this, we observed a higher microbial richness in the intestines of children colonized by Blastocystis, which could, therefore, be considered a benefit to intestinal health. The phylum Firmicutes was the predominant taxonomic unit in both groups analyzed. In Blastocystis-free individuals, there was a higher proportion of Bacteroidetes; similarly, in children colonized by Blastocystis, there was a higher relative abundance of the phylum Proteobacteria; however, no statistically significant differences were found between the comparison groups.
CONCLUSIONS
The presence of Blastocystis showed a decrease in Bacteroides, and an increase in the relative abundance of the genus Faecalibacterium. It was also evident that the presence of Blastocystis was unrelated to dysbiosis at the intestinal level; on the contrary, its presence did not show statistically differences in the intestinal microbiota composition. Nevertheless, we believe that Blastocystis plays a role in the ecology of the intestinal microbiota through its interaction with other microbial components.
Topics: Blastocystis; Blastocystis Infections; Child, Preschool; Colombia; Feces; Female; Firmicutes; Gastrointestinal Microbiome; Humans; Intestines; Male
PubMed: 33066814
DOI: 10.1186/s13071-020-04392-9 -
Annals of Agricultural and... Sep 2018is a unicellular, anaerobic protist which lives in the intestinal tract of diverse animals, including humans. It was found that the host specificity and the pathogenic... (Review)
Review
is a unicellular, anaerobic protist which lives in the intestinal tract of diverse animals, including humans. It was found that the host specificity and the pathogenic potential of different isolates are correlated with sequence variations in the SSU-rRNA gene. Identification of the organism to the species level is still an unresolved challenge. Genetic diversity revisions have led to the identification of 17 subtypes (STs) within the genus, and 9 (ST1 to ST9) have been reported in humans with varying prevalence. Since the members of the genus revealed a large genetic diversity, several molecular modalities of subtyping methods have been developed. Numerous studies on conveying the pathogenic potential to the molecular subtypes are available, but they could not be compared or analysed with the different molecular techniques employed. The use of different approaches may give false positives during diagnosis and the possibility of missed infections. A review of recent scientific literature indicates that the development of PCR assays is needed for molecular epidemiology and for mixed infections in health and disease cohorts, and also to help identify sources of transmission to humans, as well as to identify potential animal and environmental reservoirs. This review summarizes some of the recent progress and improvements in research on genetic diversity, taxonomy, molecular epidemiology, pathogenicity and subtyping methods.
Topics: Animals; Blastocystis; Blastocystis Infections; Genetic Variation; Humans; Virulence
PubMed: 30260199
DOI: 10.26444/aaem/81315 -
Biomedical Journal Sep 2023Intestinal parasitic infections are the most common infectious diseases among Southeast Asian migrant workers in Taiwan, especially for infections with Blastocystis...
BACKGROUND
Intestinal parasitic infections are the most common infectious diseases among Southeast Asian migrant workers in Taiwan, especially for infections with Blastocystis hominis. However, little is known about the impact of Blastocystis subtypes (STs) on the gut microbiota.
MATERIAL AND METHODS
We retrospectively evaluated the prevalence of intestinal parasites in a teaching hospital in Northern Taiwan in the period of 2015 to 2019. Blastocystis-positive stool specimens were collected for ST analysis by polymerase chain reaction in 2020. Intestinal microbiota analyses of different Blastocystis STs and Blastocystis-free individuals were conducted by 16S rRNA sequencing.
RESULTS
A total of 13,859 subjects were analyzed, of which 1,802 cases (13%) were diagnosed with intestinal parasitic infections. B. hominis infections were the most prevalent (n = 1546, 85.7%). ST analysis of Blastocystis-positive samples (n=150) indicated that ST1 was the most common type, followed by ST3, ST4, ST2, ST7, and ST5. Different Blastocystis STs (ST1, ST3, and ST4) were associated with distinct richness and diversity of the microbiota. Taxonomic profiles revealed that Akkermansia muciniphila was significantly enriched for all analyzed Blastocystis STs, whereas Holdemanella biformis was more abundant in the Blastocystis-free group. Additionally, Succinivibrio dextrinosolvens and Coprococcus eutactus were specifically more abundant in ST3 carriers than in non-infected individuals.
CONCLUSIONS
This study demonstrates that A. muciniphila is positively associated with all Blastocystis STs, while H. biformis was negatively associated with them. Several bacteria were enriched in specific STs, highlighting the need for further microbiota analysis at the ST level to elucidate the pathogenicity of Blastocystis.
PubMed: 37774792
DOI: 10.1016/j.bj.2023.100661 -
Parasites & Vectors Apr 2021Blastocystis sp. is a common intestinal protozoan found worldwide. Based on gene analysis, 17 subtypes (STs, ST1-ST17) have been identified, 9 of which have been...
BACKGROUND
Blastocystis sp. is a common intestinal protozoan found worldwide. Based on gene analysis, 17 subtypes (STs, ST1-ST17) have been identified, 9 of which have been isolated from humans. Differences in clinical consequences may depend on differences among the STs. Here, we evaluated the prevalence of Blastocystis sp. in patients with colorectal cancer (CRC) compared to a control group and assessed the relationships between Blastocystis sp. infection and sex; age; and CRC grade, stage, and location.
METHODS
The study included 107 CRC patients (41 women and 66 men, median age 65 years); 124 subjects without colorectal cancer or a history of oncological disease comprised the control group (55 women and 69 men, median age 63). Stool samples were collected from patients before oncological treatment and examined using light microscopy (iodine-stained smear). Additionally, PCR-based identification of Blastocystis sp. was performed in 95 stool samples from CRC patients and 76 stool samples from the control group.
RESULTS
Light microscopy showed that the prevalence of Blastocystis sp. was significantly higher in CRC patients than in the control group (12.15% and 2.42%, respectively; p = 0.0041). Multivariate analysis showed that the odds of Blastocystis sp. infection were fivefold higher in the CRC group than in the control group. PCR-based molecular examinations demonstrated that the proportion of patients infected with Blastocystis sp. was significantly higher in the CRC group than in the control group (12.63% and 2.63%, respectively; p = 0.023). The predominant ST in the CRC group was ST3, detected in nine patients (75%), followed by ST1 (2 patients, 16.7%) and ST2 (1 patient, 8.3%). No association was found between Blastocystis sp. infection and age, sex, or CRC stage, grade, or location.
CONCLUSIONS
The results showed that CRC was associated with an increased risk of opportunistic Blastocystis sp. infection, even before oncological treatment. To the best of our knowledge, this is the first report estimating the prevalence of Blastocystis sp. infection in CRC patients before oncological treatment in Europe.
Topics: Adult; Age Factors; Aged; Aged, 80 and over; Blastocystis; Blastocystis Infections; Case-Control Studies; Colorectal Neoplasms; DNA, Protozoan; Feces; Female; Humans; Male; Middle Aged; Polymerase Chain Reaction; Sex Factors
PubMed: 33853659
DOI: 10.1186/s13071-021-04681-x -
International Journal For Parasitology Oct 2023Molecular characterisation of endobionts that are shared among human and non-human hosts can help shed light on the epidemiology and inform studies that aim to unravel...
Molecular characterisation of endobionts that are shared among human and non-human hosts can help shed light on the epidemiology and inform studies that aim to unravel the role of these organisms in health and disease. Two of the most common of shared endobionts include the single-celled intestinal protists Blastocystis and Entamoeba. Here, we present the first known data on genetic diversity and host specificity of these two genera in Greenland. Faecal DNA samples from 243 muskoxen and 44 sheep were submitted to metabarcoding of nuclear small subunit ribosomal DNA. Entamoeba- and Blastocystis-specific sequences were clustered, and consensus sequences were subjected to taxonomic query. Using MinION-based sequencing, near-complete nuclear small subunit ribosomal DNA sequences were obtained from four faecal samples. Of the 243 muskox samples, 180 (74%) and 19 (8%) were positive for Blastocystis and Entamoeba, respectively. Forty (91%) and six (14%) of the 44 sheep samples were positive for Blastocystis and Entamoeba, respectively. Blastocystis subtypes (ST) 10, 14, 21, 24-26, and a novel subtype (ST40) were identified. Colonisation by more than one subtype was common. ST40 was common in muskoxen but limited to Northeast Greenland. Entamoeba bovis and the E. bovis-associated ribosomal lineages (RL) 1 and 8 were found, and three conditional lineages (CL) 3, 4, and 10 were confirmed; CL10 was promoted to RL12. Several novel lineages were identified, all of which were linked to the E. bovis complex. In conclusion, Blastocystis was far more common than Entamoeba and found in approximately three of every four animals; both can be considered common colonisers of large herbivorous mammals in Greenland. Multiple subtypes/lineages of both genera were commonly observed, some of which were novel, but most of which are seen in many other parts of the world.
Topics: Sheep; Animals; Blastocystis; Blastocystis Infections; Entamoeba; Greenland; Phylogeny; Feces; Ruminants; DNA, Ribosomal; Genetic Variation
PubMed: 37355198
DOI: 10.1016/j.ijpara.2023.05.005