Gut microbiome of helminth-infected indigenous Malaysians is context dependent

Multi-omics insights into the response of the gut microbiota and metabolites to albendazole deworming in captive Rhinopithecus brelichi

Background

Parasite infection and deworming treatment affect the host gut microbiota. Exploring the response mechanism of the gut microbiota in Rhinopithecus brelichi (R. brelichi) to albendazole deworming treatment is of great value for protecting this critically endangered species.

Methods and results

This study used metataxonomics and metabolomics to explore the responses of the gut microbiota and metabolites of R. brelichi to albendazole deworming treatment. The results showed that deworming significantly reduced the eggs per gram of feces (EPG). The 16S rRNA gene sequencing results showed that the richness and diversity of the gut microbiota in R. brelichi after deworming were significantly increased. Meanwhile, deworming treatment also changed the composition of the gut microbiota. At the genus level, the Christensenellaceae R7 group, UCG 002, UCG 005, uncultured rumen bacterium, and Rikenellaceae RC9 gut group were significantly enriched in the pre-deworming samples. Unclassified Muribaculaceae, Prevotella 9, and Bacteroides were significantly enriched in the post-deworming samples. Metabolomics analysis revealed that the relative abundance of 382 out of 1,865 metabolites showed significant differences between the pre- and post-deworming samples. Among them, 103 metabolites were annotated based on the HMDB and mainly classified into Prenol lipids, Carboxylic acids and derivatives, and Organooxygen compounds, etc. The KEGG enrichment analysis result indicated that these metabolites were mainly involved in energy, amino acid, lipid, and purine metabolism. Correlation analysis showed that Bacteroides and unclassified Muribaculaceae, whose relative abundances were upregulated after deworming treatment, were positively correlated with Kaempferol, 5,7-Dihydroxy-3-methoxy-4'-prenyloxyflavone, Purpurin, and Rhein, which have anti-parasitic activities. The Christensenellaceae R7 group, with a downregulated relative abundance after deworming treatment, was not only negatively correlated with the above four metabolites, but also positively correlated with Retinyl beta-glucuronide, which is a storage form of vitamin A, and positively correlated with CDP-Choline, which increases the host's susceptibility to Entamoeba histolytica and Plasmodium falciparum.

Conclusion

This study emphasizes that deworming treatment has an impact on the gut microbiota and metabolic functions of R. brelichi. By exploiting the correlations between differential microbiota and metabolites, potential probiotics or prebiotics can be explored, thereby enhancing the efficiency of deworming and reducing its side effects.

Gut Microbiota and Parasite Dynamics in an Amazonian Community Undergoing Urbanization in Colombia

Studies on human gut microbiota have recently highlighted a significant decline in bacterial diversity associated with urbanization, driven by shifts toward processed diets, increased antibiotic usage, and improved sanitation practices. This phenomenon has been largely overlooked in the Colombian Amazon, despite rapid urbanization in the region. In this study, we investigate the composition of gut bacterial microbiota and intestinal protozoa and soil-transmitted helminths (STHs) in both urban and rural areas of Leticia, which is located in the southern Colombian Amazon. Despite their geographic proximity, the urban population is predominantly non-indigenous, while indigenous communities mostly inhabit the rural area, resulting in notable lifestyle differences between the two settings. Our analyses reveal a reduction in bacterial families linked to non-processed diets, such as Lachnospiraceae, Spirochaetaceae, and Succinivibrionaceae, in the urban environment compared to their rural counterparts. Interestingly, Prevotellaceae, typically associated with non-processed food consumption, shows a significantly higher abundance in urban Leticia. STH infections were primarily detected in rural Leticia, while intestinal protozoa were ubiquitous in both rural and urban areas. Both types of parasites were associated with higher gut bacterial richness and diversity. Additionally, microbial metabolic prediction analysis indicated differences in pathways related to unsaturated fatty acid production and aerobic respiration between rural and urban bacterial microbiomes. This finding suggests a tendency towards dysbiosis in the urban microbiota, possibly increasing susceptibility to non-communicable chronic diseases. These findings provide new insights into the impact of urbanization on gut microbiota dynamics in the Amazonian context and underscore the need for further research to elucidate any associated health outcomes.

Coevolutionary interplay: Helminths-trained immunity and its impact on the rise of inflammatory diseases

The gut biome, a complex ecosystem of micro- and macro-organisms, plays a crucial role in human health. A disruption in this evolutive balance, particularly during early life, can lead to immune dysregulation and inflammatory disorders. 'Biome repletion' has emerged as a potential therapeutic approach, introducing live microbes or helminth-derived products to restore immune balance. While helminth therapy has shown some promise, significant challenges remain in optimizing clinical trials. Factors such as patient genetics, disease status, helminth species, and the optimal timing and dosage of their products or metabolites must be carefully considered to train the immune system effectively. We aim to discuss how helminths and their products induce trained immunity as prospective to treat inflammatory and autoimmune diseases. The molecular repertoire of helminth excretory/secretory products (ESPs), which includes proteins, peptides, lipids, and RNA-carrying extracellular vesicles (EVs), underscores their potential to modulate innate immune cells and hematopoietic stem cell precursors. Mimicking natural delivery mechanisms like synthetic exosomes could revolutionize EV-based therapies and optimizing production and delivery of ESP will be crucial for their translation into clinical applications. By deciphering and harnessing helminth-derived products' diverse modes of action, we can unleash their full therapeutic potential and pave the way for innovative treatments.

Distinct gut microbiome features characterize Fasciola hepatica infection and predict triclabendazole treatment outcomes in Peruvian patients

Background

Fasciola hepatica, a globally distributed helminth, causes fasciolosis, a disease with significant health and economic impacts. Variability in triclabendazole (TCBZ) efficacy and emerging resistance are remaining challenges. Evidence suggests that the gut microbiome influences host-helminth interactions and is associated with anthelmintic effects, but its association with human F. hepatica infection and TCBZ efficacy is not well understood.

Methods

In this study, we investigated the relationship between Fasciola hepatica infection and the gut microbiome through metagenomic shotgun sequencing of 30 infected and 60 age- and sex-matched uninfected individuals from Peru. Additionally, we performed a longitudinal analysis to evaluate microbiome dynamics in relation to TCBZ treatment response.

Results and discussion

Infection was associated with specific microbial taxonomic and functional features, including higher abundance of Negativibacillus sp900547015, Blautia A sp000285855, and Prevotella sp002299635 species, and enrichment of microbial pathways linked to survival under stress and depletion of pathways for microbial growth. Unexpectedly, we identified that responders to TCBZ treatment (who cleared infection) harbored many microbiome features significantly different relative to non-responders, both before and after treatment. Specifically, the microbiomes of responders had a higher abundance Firmicutes A and Bacteroides species as well as phospholipid synthesis and glucuronidation pathways, while non-responders had higher abundance of Actinobacteria species including several from the Parolsenella and Bifidobacterium genera, and Bifidobacterium shunt and amino acid biosynthesis pathways.

Conclusions

Our findings underscore the impact of helminth infection on gut microbiome and suggest a potential role of gut microbiota in modulating TCBZ efficacy, offering novel insights into F. hepatica-microbiome interactions and paving the way for microbiome-informed treatment approaches.

Metagenomic analysis reveals the community composition of the microbiome in different segments of the digestive tract in donkeys and cows: implications for microbiome research

INTRODUCTION

The intestinal microbiota plays a crucial role in health and disease. This study aimed to assess the composition and functional diversity of the intestinal microbiota in donkeys and cows by examining samples collected from different segments of the digestive tract using two distinct techniques: direct swab sampling and faecal sampling.

RESULTS

In this study, we investigated and compared the effects of multiple factors on the composition and function of the intestinal microbial community. Approximately 300 GB of metagenomic sequencing data from 91 samples obtained from various segments of the digestive tract were used, including swabs and faecal samples from monogastric animals (donkeys) and polygastric animals (cows). We assembled 4,004,115 contigs for cows and 2,938,653 contigs for donkeys, with a total of 9,060,744 genes. Our analysis revealed that, compared with faecal samples, swab samples presented a greater abundance of Bacteroidetes, whereas faecal samples presented a greater abundance of Firmicutes. Additionally, we observed significant variations in microbial composition among different digestive tract segments in both animals. Our study identified key bacterial species and pathways via different methods and provided evidence that multiple factors can influence the microbial composition. These findings provide new insights for the accurate characterization of the composition and function of the gut microbiota in microbiome research.

CONCLUSIONS

The results obtained by both sampling methods in the present study revealed that the composition and function of the intestinal microbiota in donkeys and cows exhibit species-specific and region-specific differences. These findings highlight the importance of using standardized sampling protocols to ensure accurate and consistent characterization of the intestinal microbiota in various animal species. The implications and underlying mechanisms of these associations provide multiple perspectives for future microbiome research.

Advancing microbiome research in Māori populations: insights from recent literature exploring the gut microbiomes of underrepresented and Indigenous peoples

The gut microbiome plays vital roles in human health, including mediating metabolism, immunity, and the gut-brain axis. Many ethnicities remain underrepresented in gut microbiome research, with significant variation between Indigenous and non-Indigenous peoples due to dietary, socioeconomic, health, and urbanization differences. Although research regarding the microbiomes of Indigenous peoples is increasing, Māori microbiome literature is lacking despite widespread inequities that Māori populations face. These inequities likely contribute to gut microbiome differences that exacerbate negative health outcomes. Characterizing the gut microbiomes of underrepresented populations is necessary to inform efforts to address health inequities. However, for microbiome research to be culturally responsible and meaningful, study design must improve to better protect the rights and interests of Indigenous peoples. Here, we discuss barriers to Indigenous participation in research and the role disparities may play in shaping the gut microbiomes of Indigenous peoples, with a particular focus on implications for Māori and areas for improvement.

Gut-microbiome profiles among Soil-transmitted helminths (STHs) infected Ethiopian children enrolled in the school-based mass deworming program

BACKGROUND

Soil-transmitted helminths (STHs) and mutualistic gut microbes coexist in the gastrointestinal tract. However, limited data exist regarding how STH infections are associated with gut microbiome profiles.

METHOD

We conducted a cross-sectional analysis of baseline data collected in a longitudinal study to identify and explain differences in microbial communities between STH-infected and non-infected Ethiopian school children. We collected 138 stool samples and analyzed them for STH infection using standard direct wet mount and Kato Katz methods. The gut microbiome profiles were characterized using targeted amplicon sequencing of the 16S rRNA gene from the total DNA extracted from the stools.

RESULTS

Children infected with Trichuris trichiura showed significantly lower microbial diversity than those who were non-infected (p<0.05). We also observed significant difference in microbiome composition based on Trichuris trichiura infection status (PERMANOVA p< 0.01). A comparison of microbial taxa at the genus level among participants infected with different helminth species showed a significant increase in Agathobacter relative abundance among children infected with Trichuris trichiura compared to non-infected subjects (adjusted p = 0.001).

CONCLUSIONS

Our results indicate that changes in the gut microbiome composition may vary depending on the species of helminth present. Further studies should investigate how Trichuris trichiura selectively alters microbiome composition compared to other STH species.

Exploring the Effect of Gastrointestinal Prevotella on Growth Performance Traits in Livestock Animals

Microorganisms in the rumen play a crucial role in determining the most efficient utilization rate of nutrients. Among these microorganisms, Prevotella stands out as one of the most representative bacteria within the rumen biological system. Prevotella is a common strict anaerobic bacterium that is found in the gastrointestinal tract of livestock. Prevotella plays a crucial role in breaking down and metabolizing complex nutrients like cellulose and protein during food digestion. Moreover, it is capable of working together with other bacteria in the body's digestive system. Several studies have shown a strong correlation between the abundance of Prevotella and livestock growth performance. This paper provides a comprehensive review of the current research on the function, mechanisms, and applications of Prevotella in the gastrointestinal tract. The insights provided in this review could serve as a theoretical basis for accurately classifying Prevotella, further investigating its effects and potential mechanisms on livestock growth performance, and exploring its practical applications.

Taeniasis impacts human gut microbiome composition and function

Human taeniasis, caused by Taenia tapeworms, is a global parasitic disease with significant implications for public health and food safety. These tapeworms can grow to considerable sizes and potentially impact the microecology of the host gut. Despite their importance, the effects of Taenia infection on host gut microbiota haven't been thoroughly investigated. In this study, we conducted a cross-sectional analysis of the gut microbiome in patients infected with Taenia asiatica (n = 87) compared to healthy controls (n = 79) in the Dali cohort, China. We also performed a longitudinal assessment of microbial changes following deworming in a subset of patients (n = 24). Our findings reveal a significant shift in gut microbial composition, characterized by increased alpha-diversity and an enrichment of Prevotella-driven enterotypes in infected patients compared to healthy controls. The stability of these microbial features post-deworming varied widely among individuals and was lower in those with lower initial alpha diversity and Prevotella-enterotype before deworming. We observed a significant depletion of Bifidobacterium species in infected individuals, regardless of enterotypes, and these prebiotics did not recover post-deworming. Metabolic network analysis and in vitro experiments suggest that the reduction of Bifidobacterium was linked to metabolic competition for ecological niches or nutrients, particularly stachyose, from other microbes rather than the parasitism itself. Furthermore, our machine learning analysis demonstrated that taxa associated with Bifidobacterium in stachyose metabolism could robustly predict infection but could not predict deworming. This study highlights the substantial impact of taeniasis on the human gut microbiome and overall gut health.

Zinc status or supplementation and its relation to soil-transmitted helminthiasis in children: A systematic review

Soil-transmitted helminths (STHs) parasitic infection is known as one of the most common infections around the world affecting more than a quarter of the world's population. The relationship between STH infections and micronutrient deficiencies are closely related and often coexist among the affected population. The study, therefore, aimed to summarise the available literature focusing on the effect of zinc status/deficiency or supplementation on STH infection or reinfection in children. For this purpose, we adopted a systematic approach and searched the existing literature on PubMed, Scopus, and Cochrane Library databases. A search term was entered to retrieve the available data. A total of 12 articles were included in this review after applying the inclusion/exclusion criteria. Most of the included studies reported a lower zinc status in children affected with any parasitic infection. Regarding the effect of zinc status and supplementation on parasitic infection in children, we found only a few studies (n = 4) with inconsistent result findings. This review reported that children infected with STH have lower zinc levels; however, a limited number of studies showed the effect of zinc supplements on the risk of STH warrants the need for further studies in this regard.

A relational framework for microbiome research with Indigenous communities

Ethical practices in human microbiome research have failed to keep pace with scientific advances in the field. Researchers seeking to 'preserve' microbial species associated with Indigenous groups, but absent from industrialized populations, have largely failed to include Indigenous people in knowledge co-production or benefit, perpetuating a legacy of intellectual and material extraction. We propose a framework centred on relationality among Indigenous peoples, researchers and microbes, to guide ethical microbiome research. Our framework centres accountability to flatten historical power imbalances that favour researcher perspectives and interests to provide space for Indigenous worldviews in pursuit of Indigenous research sovereignty. Ethical inclusion of Indigenous communities in microbiome research can provide health benefits for all populations and reinforce mutually beneficial partnerships between researchers and the public.

Bacterial contact induces polar plug disintegration to mediate whipworm egg hatching

The bacterial microbiota promotes the life cycle of the intestine-dwelling whipworm Trichuris by mediating hatching of parasite eggs ingested by the mammalian host. Despite the enormous disease burden associated with Trichuris colonization, the mechanisms underlying this transkingdom interaction have been obscure. Here, we used a multiscale microscopy approach to define the structural events associated with bacteria-mediated hatching of eggs for the murine model parasite Trichuris muris. Through the combination of scanning electron microscopy (SEM) and serial block face SEM (SBFSEM), we visualized the outer surface morphology of the shell and generated 3D structures of the egg and larva during the hatching process. These images revealed that exposure to hatching-inducing bacteria catalyzed asymmetric degradation of the polar plugs prior to exit by the larva. Unrelated bacteria induced similar loss of electron density and dissolution of the structural integrity of the plugs. Egg hatching was most efficient when high densities of bacteria were bound to the poles. Consistent with the ability of taxonomically distant bacteria to induce hatching, additional results suggest chitinase released from larva within the eggs degrade the plugs from the inside instead of enzymes produced by bacteria in the external environment. These findings define at ultrastructure resolution the evolutionary adaptation of a parasite for the microbe-rich environment of the mammalian gut.

Improved eukaryotic detection compatible with large-scale automated analysis of metagenomes

BACKGROUND

Eukaryotes such as fungi and protists frequently accompany bacteria and archaea in microbial communities. Unfortunately, their presence is difficult to study with "shotgun" metagenomic sequencing since prokaryotic signals dominate in most environments. Recent methods for eukaryotic detection use eukaryote-specific marker genes, but they do not incorporate strategies to handle the presence of eukaryotes that are not represented in the reference marker gene set, and they are not compatible with web-based tools for downstream analysis.

RESULTS

Here, we present CORRAL (for Clustering Of Related Reference ALignments), a tool for the identification of eukaryotes in shotgun metagenomic data based on alignments to eukaryote-specific marker genes and Markov clustering. Using a combination of simulated datasets, mock community standards, and large publicly available human microbiome studies, we demonstrate that our method is not only sensitive and accurate but is also capable of inferring the presence of eukaryotes not included in the marker gene reference, such as novel strains. Finally, we deploy CORRAL on our MicrobiomeDB.org resource, producing an atlas of eukaryotes present in various environments of the human body and linking their presence to study covariates.

CONCLUSIONS

CORRAL allows eukaryotic detection to be automated and carried out at scale. Implementation of CORRAL in MicrobiomeDB.org creates a running atlas of microbial eukaryotes in metagenomic studies. Since our approach is independent of the reference used, it may be applicable to other contexts where shotgun metagenomic reads are matched against redundant but non-exhaustive databases, such as the identification of bacterial virulence genes or taxonomic classification of viral reads. Video Abstract.