Microbiota and parasite relationship

Range-Wide Assessment of the Tasmanian Devil Gut Microbiome

The gut microbiome is an important component of host health and function and is influenced by internal and external factors such as host phylogeny, age, diet, and environment. Monitoring the gut microbiome has become an increasingly important management tool for wild populations of threatened species. The Tasmanian devil (Sarcophilus harrisii) is the largest extant carnivorous marsupial from the island state of Tasmania, Australia. Devils are currently endangered due to devil facial tumor disease. Previous assessments have shown differences between captive and wild devil gut microbiomes and changes during translocations. However, wild gut microbiome variability across Tasmania and the drivers of these differences are not well understood. We conducted a range-wide assessment of gut microbiomes at 10 locations across Tasmania, via 16S rRNA sequencing, and tested the influence of diet (12S vertebrate sequencing), location, sex, and cohort. We show that the five most abundant phyla and genera were consistent across all 10 locations. Location, cohort, and sex impacted bacterial richness, but location did not impact diversity. While there were differences in diet across the state, there was no strong evidence of differences between juveniles and adults, nor between males and females. Contrary to our hypothesis, the vertebrate diet explained a small amount of variation in microbial communities. We suspect that other variables, such as environmental factors and immune system development, may have a stronger influence on gut microbiome variability. Dietary components missed by our 12S primer, including invertebrates and plants, may also contribute to these patterns. Adjustments to dietary supplementation are not recommended when preparing devils for translocation to different sites. Future research should prioritize collecting environmental samples for microbial analysis and integrating metabolomics to elucidate functional differences associated with Tasmanian devil gut microbiome variability.

Helminth-induced immune modulation in colorectal cancer: exploring therapeutic applications

Colorectal cancer is one of the most lethal tumors, posing a financial and healthcare burden. This study investigates how helminths and pre-existing diseases such as colitis, obesity, diabetes, and gut microbiota issues influence colon cancer development and prognosis. The immune system's protective immunosuppressive response to helminth invasion minimizes inflammation-induced cell damage and DNA mutations, lowering the risk of colorectal cancer precursor lesions. Helminth infection-mediated immunosuppression can hasten colorectal cancer growth and metastasis, which is detrimental to patient outcomes. Some helminth derivatives can activate immune cells to attack cancer cells, making them potentially useful as colorectal cancer vaccines or therapies. This review also covers gene editing approaches. We discovered that using CRISPR/Cas9 to inhibit live helminths modulates miRNA, which limits tumor growth. We propose more multicenter studies into helminth therapy's long-term effects and immune regulation pathways. We hope to treat colorectal cancer patients with helminth therapy and conventional cancer treatments in an integrative setting.

Behavioral Cooperation or Conflict of Human Intestinal Roundworms and Microbiomes: A Bio-Activity Perspective

Human infections are greatly impacted by intestinal nematodes. These nematodes, which encompass the large roundworms, have a direct impact on human health and well-being due to their close cohabitation with the host's microorganisms. When nematodes infect a host, the microbiome composition changes, and this can impact the host's ability to control the parasites. We aimed to find out if the small intestinal roundworms produce substances that have antimicrobial properties and respond to their microbial environment, and if the immune and regulatory reactions to nematodes are altered in humans lacking gut microbes. There is no doubt that different nematodes living in the intestines can alter the balance of intestinal bacteria. Nonetheless, our knowledge about the parasite's influence on the gut microbiome remains restricted. The last two decades of study have revealed that the type of iron utilized can influence the activation of unique virulence factors. However, some roundworm proteins like P43, which makes up a large portion of the worm's excretory-secretory product, have an unknown role. This review explores how the bacterial iron regulatory network contributes to the adaptability of this opportunistic pathogen, allowing it to successfully infect nematodes in different host environments.

Network Analysis of Pathogenesis Markers in Murine Chagas Disease Under Antimicrobial Treatment

Chagas disease (CD), a disease affecting millions globally, remains shrouded in scientific uncertainty, particularly regarding the role of the intestinal microbiota in disease progression. This study investigates the effects of antibiotic-induced microbiota depletion on parasite burden, immune responses, and clinical outcomes in BALB/c mice infected with either the Trypanosoma cruzi Colombiana or CL Brener strains. Mice were treated with a broad-spectrum antibiotic cocktail before infection, and parasite burden was quantified via qPCR at 30 and 100 days post-infection (dpi). Immune responses were analyzed using flow cytometry and ELISA, while histopathology was conducted on cardiac and intestinal tissues. Antibiotic treatment uncovered strain-specific correlations, with Colombiana infections affecting Bifidobacterium populations and CL Brener infections linked to Lactobacillus. Microbiota depletion initially reduced parasite burden in the heart and intestine, but an increase was observed in the chronic phase, except in the CL Brener-infected gut, where an early burden spike was followed by a decline. Antibiotic-induced bacterial shifts, such as reductions in Bacteroides and Bifidobacterium, promoted a more pro-inflammatory immune profile. These findings highlight the importance of microbiota and strain-specific factors in CD and suggest further research into microbiota manipulation as a potential therapeutic strategy.

Gut microbiome profile to the level species in diarrheic protozoan-carrier patients in Italy

The human gastrointestinal microbiota contains a diverse consortium of microbes, including bacteria, protozoa, viruses, and fungi that are involved in many physiological and metabolic as well pathogenetic processes. However, microbiological research is dominated by studies describing the impact of prokaryotic bacteria on gut microbiome with a limited understanding of their relationship with other integral microbiota constituents as protozoa. Here, we investigated the gut microbiome composition using Oxford Nanopore Technology approach in relation to protozoan colonization of Giardia duodenalis, Cryptosporidium parvum, Blastocystis sp. and Dientamoeba fragilis in patients with diarrheal diseases in Italy, taking into consideration different risk factors as protozoan coinfection, Blastocystis-subtypes, gender, age classes, origin, eosinophilia level and positivity to SARS-CoV-2 infection. Overall, out of 1413 investigated patients, 123 (8.7 %) have found positive to one or more protozoan microorganisms with a prevalence statistically significant in individuals from Northern Africa (p < 0.0001) and in the age classes 40-59 years-old (p < 0.0022). Within the 57 individuals eligible for gut microbiome analysis, diverse profiles are observed but interestingly, a predominance of the emergent Escherichia fergusonii ATCC 35469, was found across the different risk factors. Our results emphasize the importance of studies to investigate these aspects of protozoa colonization that will undoubtedly increase our understanding of complex interactions between intestinal protozoa, other microbiota organisms, and the human host.

Schistosomiasis-Microbiota Interactions: A Systematic Review and Meta-Analysis

INTRODUCTION

Schistosomiasis, a tropical disease affecting humans and animals, affected 251.4 million people in 2021. Schistosoma mansoni, S. haematobium, S. intercalatum, and S. japonicum are primary human schistosomes, causing tissue damage, granulomas, ulceration, hemorrhage, and opportunistic pathogen entry. The gut and urinary tract microbiota significantly impact a host's susceptibility to schistosomiasis, disrupting microbial balance; however, this relationship is not well understood. This systematic review and meta-analysis explores the intricate relationship between schistosomiasis and the host's microbiota, providing crucial insights into disease pathogenesis and management.

METHODS

This systematic review used PRISMA guidelines to identify peer-reviewed articles on schistosomiasis and its interactions with the host microbiome, using multiple databases and Google Scholar, providing a robust dataset for analysis. The study utilized Meta-Mar v3.5.1; descriptive tests, random-effects models, and subgroups were analyzed for the interaction between Schistosomiasis and the microbiome. Forest plots, Cochran's Q test, and Higgins' inconsistency statistic (I2) were used to assess heterogeneity.

RESULTS

The human Schistosoma species were observed to be associated with various bacterial species isolated from blood, stool, urine, sputum, skin, and vaginal or cervical samples. A meta-analysis of the interaction between schistosomiasis and the host microbiome, based on 31 studies, showed 29,784 observations and 5871 events. The pooled estimates indicated a significant association between schistosomiasis and changes in the microbiome of infected individuals. There was considerable heterogeneity with variance effect sizes (p < 0.0001). Subgroup analysis of Schistosoma species demonstrated that S. haematobium was the most significant contributor to the overall heterogeneity, accounting for 62.1% (p < 0.01). S. mansoni contributed 13.0% (p = 0.02), and the coinfection of S. haematobium and S. mansoni accounted for 16.8% of the heterogeneity (p < 0.01), contributing to the variability seen in the pooled analysis. Similarly, praziquantel treatment (RR = 1.68, 95% CI: 1.07-2.64) showed high heterogeneity (Chi2 = 71.42, df = 11, p < 0.01) and also indicated that Schistosoma infections in males (RR = 1.46, 95% CI: 0.00 to 551.30) and females (RR = 2.09, 95% CI: 0.24 to 18.31) have a higher risk of altering the host microbiome.

CONCLUSIONS

Schistosomiasis significantly disrupts the host microbiota across various bodily sites, leading to increased susceptibility to different bacterial taxa such as E. coli, Klebsiella, Proteus, Pseudomonas, Salmonella, Staphylococcus, Streptococcus, and Mycobacterium species (M. tuberculosis and M. leprae). This disruption enables these bacteria to produce toxic metabolites, which in turn cause inflammation and facilitate the progression of disease. The impact of schistosomiasis on the vaginal microbiome underscores the necessity for gender-specific approaches to treatment and prevention. Effective management of female genital schistosomiasis (FGS) requires addressing both the parasitic infection and the resulting microbiome imbalances. Additionally, praziquantel-treated individuals have different microbiome compositions compared to individuals with no praziquantel treatment. This suggests that combining praziquantel treatment with probiotics could potentially decrease the disease severity caused by an altered microbiome.

Parasites and Microbiota: Dual Interactions and Therapeutic Perspectives

The human gut hosts a diverse and active community of bacteria that symbiotically support the physiology, metabolism, and immunity of the intestinal lining. Nevertheless, a dynamic community of parasites (helminths and protozoa) may share a habitat with gut-dwelling microbiota. Both microbiota and parasites can significantly change the physical and immunological environment of the gut, thus generating several mechanisms of interaction. Studying this field is crucial for understanding the pathogenesis of parasitic diseases. Additionally, intestinal microbiota and gut-dwelling parasites may interact with each other and with the host immunity to alleviate or exacerbate the disease. These interactions can alter the pathogenicity of both parasites and microbiota, thereby changing the infection outcomes and the overall disease profile. Parasites and microbiota interactions occur via several mechanisms, including physical alteration in both the gastrointestinal microenvironment and the adaptive and innate immune responses. By modulating the microbiota, treating parasitic infections and microbiota dysbiosis may be improved through knowing the mechanisms and consequences of the interactions between intestinal parasites and the microbiota. Thus, new biological tools of treatment including probiotics can be introduced, particularly with the emergence of drug resistance and adverse effects.

Regulation Effect of Toxocara canis and Anthelmintics on Intestinal Microbiota Diversity and Composition in Dog

Toxocara canis is an intestinal roundworm that can cause serious zoonotic parasitic diseases. Drontal Plus® Tasty (Dog) is a kind of commercial drug used to treat T. canis infection. Febantel, Praziquantel, and Pyrantel pamoate (PP) are its main component. However, there are few studies investigating the impact of Drontal Plus® Tasty (Dog) and its primary ingredients on the intestinal microbiota of dogs. In this study, we first collected the intestinal content samples of the dogs which administrated with anthelmintics or saline by sterile catheters, then used 16S rRNA high-throughput sequencing technology combined with a variety of bioinformatic analysis methods to analyze the effect of anthelmintics on intestinal microbiota. First, the results of the α and β diversity analysis showed that the abundance and diversity of intestinal microbiota decreased with T. canis infection, and increased after anthelmintic treatment. Then, we found the dominant species (the value of relative abundance > 0.05) was both 28 on phylum and genus levels, besides the most dominant species was Bacillota on phylum level and Segatella and Clostridium_sensu_stricto were most dominant on genus level. Futher analyzing the differences in microbiotal composition on phylum level, we found that Drontal Plus® Tasty treatment could significantly increase the proportion of Bacillota, while Febantel, Praziquantel, or PP could induce the significantly changes of Bacillota and Bacteroidota. In addition, by analyzing the differences in microbiotal composition on genus level, we found that anthelmintic could significantly decreased the relative abundance of Clostridium_sensu_stricto and significantly increased the abundance of Segatella. However, Drontal Plus® Tasty had no regulatory effect on the abundance of Segatella. In short, these finding showed that various anthelmintics all have significant effects for changing the abundance and diversity of host intestinal microbiota.

Interaction between Intestinal Parasites and the Gut Microbiota: Implications for the Intestinal Immune Response and Host Defence

Intestinal parasites, including helminths and protozoa, account for a significant portion of the global health burden. The gastrointestinal (GI) tract not only serves as the stage for these parasitic infections but also as the residence for millions of microbes. As the intricacies of the GI microbial milieu continue to unfold, it is becoming increasingly apparent that the interactions between host, parasite, and resident microbes help dictate parasite survival and, ultimately, disease outcomes. Across both clinical and experimental models, intestinal parasites have been shown to impact microbial composition and diversity. Reciprocally, microbes can directly influence parasitic survival, colonization and expulsion. The gut microbiota can also indirectly impact parasites through the influence and manipulation of the host. Studying this host-parasite-microbiota axis may help bring about novel therapeutic strategies for intestinal parasitic infection as well as conditions such as inflammatory bowel disease (IBD). In this review, we explore the relationship between intestinal parasites, with a particular focus on common protozoa and helminths, and the gut microbiota, and how these interactions can influence the host defence and intestinal immune response. We will also explore the impact of this tripartite relationship in a clinical setting and its broader implications for human health.

Sickle Cell Disease and Gut Health: The Influence of Intestinal Parasites and the Microbiome on Angolan Children

Parasitic infections are a common problem in developing countries and can intensify morbidity in patients with sickle cell disease (SCD), increasing the severity of anemia and the need for transfusions. It has been demonstrated that both helminths and protozoa can affect gut microbiome composition. On the other hand, the presence of specific bacterial communities can also influence parasite establishment. Considering this, our aim was to associate the presence of intestinal parasites with the results of hematological analyses and microbiome composition evaluations in a population of Angolan children with and without SCD. A total of 113 stool samples were collected, and gut microbiome analysis was performed using 16S sequencing and real-time PCR to detect eight different intestinal parasites. In our population, more than half of children (55%) had at least one parasitic infection, and of these, 43% were co-infected. Giardia intestinalis and Ascaris lumbricoides were more frequently found in children from the rural area of Bengo. Moreover, SCD children with ascariasis exhibited higher values of leukocytes and neutrophils, whereas the total hemoglobin levels were lower. In regards to the gut microbiome, the presence of intestinal parasites lowered the prevalence of some beneficial bacteria, namely: Lactobacillus, Bifidobacterium, Cuneatibacter, Bacteroides uniformis, Roseburia, and Shuttleworthia. This study presents the prevalence of several intestinal parasites in a high-risk transmission area with scarce information and opens new perspectives for understanding the interaction between parasites, the microbiome, and SCD.

Causal effect between gut microbiota and metabolic syndrome in European population: a bidirectional mendelian randomization study

BACKGROUND

Observational studies have reported that gut microbiota composition is associated with metabolic syndrome. However, the causal effect of gut microbiota on metabolic syndrome has yet to be confirmed.

METHODS

We performed a bidirectional Mendelian randomization study to investigate the causal effect between gut microbiota and metabolic syndrome in European population. Summary statistics of gut microbiota were from the largest available genome-wide association study meta-analysis (n = 13,266) conducted by the MiBioGen consortium. The summary statistics of outcome were obtained from the most comprehensive genome-wide association studies of metabolic syndrome (n = 291,107). The inverse-variance weighted method was applied as the primary method, and the robustness of the results was assessed by a series of sensitivity analyses.

RESULTS

In the primary causal estimates, Actinobacteria (OR = 0.935, 95% CI = 0.878-0.996, P = 0.037), Bifidobacteriales (OR = 0.928, 95% CI = 0.868-0.992, P = 0.028), Bifidobacteriaceae (OR = 0.928, 95% CI = 0.868-0.992, P = 0.028), Desulfovibrio (OR = 0.920, 95% CI = 0.869-0.975, P = 0.005), and RuminococcaceaeUCG010 (OR = 0.882, 95% CI = 0.803-0.969, P = 0.009) may be associated with a lower risk of metabolic syndrome, while Lachnospiraceae (OR = 1.130, 95% CI = 1.016-1.257, P = 0.025), Veillonellaceae (OR = 1.055, 95% CI = 1.004-1.108, P = 0.034) and Olsenella (OR = 1.046, 95% CI = 1.009-1.085, P = 0.015) may be linked to a higher risk for metabolic syndrome. Reverse MR analysis demonstrated that abundance of RuminococcaceaeUCG010 (OR = 0.938, 95% CI = 0.886-0.994, P = 0.030) may be downregulated by metabolic syndrome. Sensitivity analyses indicated no heterogeneity or horizontal pleiotropy.

CONCLUSIONS

Our Mendelian randomization study provided causal relationship between specific gut microbiota and metabolic syndrome, which might provide new insights into the potential pathogenic mechanisms of gut microbiota in metabolic syndrome and the assignment of effective therapeutic strategies.

Evaluation of reference genes for gene expression analysis by real-time quantitative PCR (qPCR) in different tissues from mice infected by Ascaris suum

Human ascariasis is the most prevalent helminth infection, affecting 445 million people worldwide. To better understand the impact of the immune system on the pathophysiology of individuals infected with Ascaris suum, mice have been used as experimental models. The RT-qPCR technique is a critical auxiliary tool of investigation used to quantify mRNA levels. However, proper normalization using reference genes is essential to ensure reliable outcomes to avoid analytical errors and false results. Despite the importance of reference genes for experimental A. suum infection studies, no specific reference genes have been identified yet. Therefore, we conducted a study to assess five potential reference genes (GAPDH, 18s, ACTB, B2M, and HPRT1) in different tissues (liver, lungs, small and large intestines) affected by A. suum larval migration in C57BL/6j mice. Tissue collection was carried out to analyze parasite burden and confirm the presence of larvae during the peak of migration in each tissue. Upon confirmation, we analyzed different genes in the tissues and found no common gene with stable expression. Our results highlight the importance of analyzing different genes and using different software programs to ensure reliable relative expression results. Based on our findings, B2M was ranked as the ideal reference gene for the liver, while 18S was the most stable gene in the lung and small intestine. ACTB, or a combination of ACTB with GAPDH, was deemed suitable as reference genes for the large intestine due to their stable expression and less variation between the control and infected groups. To further demonstrate the impact of using different reference genes, we normalized the expression of a chemokine gene (CXCL9) in all tissues. Significant differences in CXCL9 expression levels were observed between different groups in all tissues except for the large intestine. This underscores the importance of selecting appropriate reference genes to avoid overestimating target gene expression levels and encountering normalization-related issues that can lead to false results. In conclusion, our study highlights the significance of using reliable reference genes for accurate RT-qPCR analysis, especially in the context of A. suum infection studies in different tissues. Proper normalization is crucial to ensure the validity of gene expression data and avoid potential pitfalls in interpreting results.

Molecular prevalence and subtype distribution of Blastocystis spp. among children who have diarrheia or are asymptomatic in Wenzhou, Zhejiang Province, China

Blastocystis sp., a significant zoonotic parasite with a global distribution, was the focus of this study, which aimed to investigate its prevalence and genetic diversity among diarrheic and asymptomatic children in Wenzhou, China. We collected 1,032 fecal samples from Yuying Children's Hospital, Wenzhou, China, comprising 684 from children with diarrhea and 348 from asymptomatic children. Genomic DNA extracted from these samples was used to detect Blastocystis spp. by PCR, targeting the small subunit ribosomal RNA gene. Subsequently, a phylogenetic tree was constructed, applying the maximum likelihood method. Blastocystis spp. were detected in 67 (6.5%) of the fecal samples. The prevalence rate of Blastocystis spp. in diarrheic children (8.8%; 60/684) was significantly higher than that in asymptomatic children (2.0%; 7/348) (χ 2 = 17.3, p < 0.001). Sequence analysis of the SSU rRNA gene identified five known Blastocystis spp. subtypes, ST1 (n = 12), ST2 (n = 5), ST3 (n = 35), ST4 (n = 12), and ST7 (n = 3). ST1 and ST3 were present in both diarrheic and asymptomatic children, while ST2, ST4, and ST7 were exclusive to diarrheic children. Intra-subtype genetic polymorphisms were identified, comprising four variations in ST1 (ST1-1 to ST1-4), five in ST3 (ST3-1 to ST3-5), two in ST4 (ST4-1 and ST4-2), and two in ST7 (ST7-1 and ST7-2). Notably, ST1-2 to ST1-4, ST3-3 to ST3-5, and ST7-1 and ST7-2 represent newly identified variations. The composition and genetic characteristics of subtypes among children in this region suggest various sources of infection, including human-to-human and animal-to-human transmission.

Parasitosis by Fasciola hepatica and Variations in Gut Microbiota in School-Aged Children from Peru

(1) Background: Human fascioliasis is considered an endemic and hyper-endemic disease in the Peruvian Andean valleys. Our objective was to determine variations in the composition of the gut microbiota among children with Fasciola hepatica and children who do not have this parasitosis. (2) Method: A secondary analysis was performed using fecal samples stored in our biobank. The samples were collected as part of an epidemiological Fasciola hepatica cross-sectional study in children from 4 through 14 years old from a community in Cajamarca, Peru. (3) Results: In a comparison of the bacterial genera that make up the intestinal microbiota between the F. hepatica positive and negative groups, it was found that there are significant differences in the determination of Lactobacillus (p = 0.010, CI: 8.5-61.4), Bacteroides (p = 0.020, CI: 18.5-61.4), Clostridium (p < 0.001, CI: 3.5-36.0), and Bifidobacterium (p = 0.018, CI: 1.1-28.3), with each of these genera being less frequent in children parasitized with F. hepatica. (4) Conclusions: These results show that F. hepatica may be associated with direct or indirect changes in the bacterial population of the intestinal microbiota, particularly affecting three bacterial genera.

Bioinformatics analysis of the diversity of gut microbiota and different microbiota on insulin resistance in diabetes mellitus patients

It aimed to explore the diversity of gut microbiota (GM) and the effect of different microbiota on insulin resistance in diabetes mellitus (DM) patients through bioinformatics analysis.

MATERIAL AND METHOD

Microarray data were obtained from GEO database. GM samples from DM patients and healthy controls were collected, and 16S rRNA gene sequencing was carried out adopting high-throughput sequencing technology. The differential expression genes were screened using the Qlucore Omics Explorer 3.0 software. Subsequently, online tools such as STRING and DAVID were utilized for bioinformatics analysis of the differential expression genes. The differences in bacterial diversity between DM patients and healthy controls were evaluated by analyzing the diversity indicators of the microbiota, such as Shannon and Chao1 indexes. Differential abundance and functional prediction analysis were adopted to explore the different microbiota and its possible metabolic pathways between DM patients and controls. And differences in insulin resistance in specific bacterial taxa were analyzed.

RESULT

GM diversity between DM patients and controls had significant differences. GM diversity was lower in DM patients compared with controls, as indicated by a decrease in Shannon and Chao1 indexes. The differential abundance analysis showed that there were multiple different bacterial communities between DM patients and controls, including some bacterial communities at the genus-level. Functional prediction analysis also revealed potential metabolic pathways related to GM and insulin resistance in DM patients. HEXB, ZC3H12A, CCR, CXCR3, GBR10, CDK9, TXN, IGFBP3, PDHA1, and NDUFB3 genes may be potential targets for treatment.

CONCLUSION

There are differences in GM diversity between DM patients and healthy controls, and the different microbiota may be related to the occurrence and development of insulin resistance.

Therapeutic Approach Targeting Gut Microbiome in Gastrointestinal Infectious Diseases

While emerging evidence highlights the significance of gut microbiome in gastrointestinal infectious diseases, treatments like Fecal Microbiota Transplantation (FMT) and probiotics are gaining popularity, especially for diarrhea patients. However, the specific role of the gut microbiome in different gastrointestinal infectious diseases remains uncertain. There is no consensus on whether gut modulation therapy is universally effective for all such infections. In this comprehensive review, we examine recent developments of the gut microbiome's involvement in several gastrointestinal infectious diseases, including infection of Helicobacter pylori, Clostridium difficile, Vibrio cholerae, enteric viruses, Salmonella enterica serovar Typhimurium, Pseudomonas aeruginosa Staphylococcus aureus, Candida albicans, and Giardia duodenalis. We have also incorporated information about fungi and engineered bacteria in gastrointestinal infectious diseases, aiming for a more comprehensive overview of the role of the gut microbiome. This review will provide insights into the pathogenic mechanisms of the gut microbiome while exploring the microbiome's potential in the prevention, diagnosis, prediction, and treatment of gastrointestinal infections.