-
Diagnostic Microbiology and Infectious... Aug 2023The diversity of microbiota is different in each person. Many health problems such as autoimmune diseases, diabetes, cardiovascular diseases, and depression can be... (Review)
Review
The diversity of microbiota is different in each person. Many health problems such as autoimmune diseases, diabetes, cardiovascular diseases, and depression can be caused by microbiota imbalance. Since the parasite needs a host to survive, it interacts closely with the microbiota elements. Blastocystis acts on the inflammatory state of the intestine and may cause various gastrointestinal symptoms, on the contrary, it is more important for gut health because it causes bacterial diversity and richness. Blastocystis is associated with changes in gut microbiota composition, the ultimate indicator of which is the Firmicutes/Bacteroidetes ratio. The Bifidobacterium genus was significantly reduced in IBS patients and Blastocystis, and there is a significant decrease in Faecalibacterium prausnitzii, which has anti-inflammatory properties in Blastocystis infection without IBS. Lactobacillus species reduce the presence of Giardia, and the produced bacteriocins prevent parasite adhesion. The presence of helminths has been strongly associated with the transition from Bacteroidetes to Firmicutes and Clostridia. Contrary to Ascaris, alpha diversity in the intestinal microbiota decreases in chronic Trichuris muris infection, and growth and nutrient metabolism efficiency can be suppressed. Helminth infections indirectly affect mood and behavior in children through their effects on microbiota change. The main and focus of this review is to address the relationship of parasites with microbiota elements and to review the data about what changes they cause. Microbiota studies have gained importance recently and it is thought that it will contribute to the treatment of many diseases as well as in the fight against parasitic diseases in the future.
Topics: Animals; Humans; Bacteroidetes; Blastocystis; Blastocystis Infections; Feces; Firmicutes; Gastrointestinal Microbiome; Irritable Bowel Syndrome; Microbiota; Parasites
PubMed: 37267741
DOI: 10.1016/j.diagmicrobio.2023.115954 -
Nature Microbiology Jul 2023For Plasmodium falciparum, the most widespread and virulent malaria parasite that infects humans, persistence depends on continuous asexual replication in red blood...
For Plasmodium falciparum, the most widespread and virulent malaria parasite that infects humans, persistence depends on continuous asexual replication in red blood cells, while transmission to their mosquito vector requires asexual blood-stage parasites to differentiate into non-replicating gametocytes. This decision is controlled by stochastic derepression of a heterochromatin-silenced locus encoding AP2-G, the master transcription factor of sexual differentiation. The frequency of ap2-g derepression was shown to be responsive to extracellular phospholipid precursors but the mechanism linking these metabolites to epigenetic regulation of ap2-g was unknown. Through a combination of molecular genetics, metabolomics and chromatin profiling, we show that this response is mediated by metabolic competition for the methyl donor S-adenosylmethionine between histone methyltransferases and phosphoethanolamine methyltransferase, a critical enzyme in the parasite's pathway for de novo phosphatidylcholine synthesis. When phosphatidylcholine precursors are scarce, increased consumption of SAM for de novo phosphatidylcholine synthesis impairs maintenance of the histone methylation responsible for silencing ap2-g, increasing the frequency of derepression and sexual differentiation. This provides a key mechanistic link that explains how LysoPC and choline availability can alter the chromatin status of the ap2-g locus controlling sexual differentiation.
Topics: Animals; Humans; Parasites; Histones; Sex Differentiation; Methylation; Epigenesis, Genetic; Malaria; Chromatin; Phosphatidylcholines; Phospholipids
PubMed: 37277533
DOI: 10.1038/s41564-023-01396-w -
Infectious Diseases of Poverty Nov 2023Gastropoda, the largest class within the phylum Mollusca, houses diverse gut microbiota, and some gastropods serve as intermediate hosts for parasites. Studies have... (Review)
Review
BACKGROUND
Gastropoda, the largest class within the phylum Mollusca, houses diverse gut microbiota, and some gastropods serve as intermediate hosts for parasites. Studies have revealed that gut bacteria in gastropods are associated with various biological aspects, such as growth, immunity and host-parasite interactions. Here, we summarize our current knowledge of gastropod gut microbiomes and highlight future research priorities and perspectives.
METHODS
A literature search was undertaken using PubMed, Web of Science and CNKI for the articles on the gut microbiota of gastropods until December 31, 2022. We retrieved a total of 166 articles and identified 73 eligible articles for inclusion in this review based on the inclusion and exclusion criteria.
RESULTS
Our analysis encompassed freshwater, seawater and land snails, with a specific focus on parasite-transmitting gastropods. We found that most studies on gastropod gut microbiota have primarily utilized 16S rRNA gene sequencing to analyze microbial composition, rather than employing metagenomic, metatranscriptomic, or metabolomic approaches. This comprehensive review provided an overview of the parasites carried by snail species in the context of gut microbiota studies. We presented the gut microbial trends, a comprehensive summary of the diversity and composition, influencing factors, and potential functions of gastropod gut microbiota. Additionally, we discussed the potential applications, research gaps and future perspectives of gut microbiomes in parasite-transmitting gastropods. Furthermore, several strategies for enhancing our comprehension of gut microbiomes in snails were also discussed.
CONCLUSIONS
This review comprehensively summarizes the current knowledge on the composition, potential function, influencing factors, potential applications, limitations, and challenges of gut microbiomes in gastropods, with a specific emphasis on parasite-transmitting gastropods. These findings provide important insights for future studies aiming to understand the potential role of gastropod gut microbiota in controlling snail populations and snail-borne diseases.
Topics: Animals; Parasites; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Snails; Host-Parasite Interactions
PubMed: 38001502
DOI: 10.1186/s40249-023-01159-z -
Current Biology : CB Aug 2023Microtubules are a key component of eukaryotic cell architecture. Regulation of the dynamic growth and shrinkage of microtubules gives cells their shape, allows cells to...
Microtubules are a key component of eukaryotic cell architecture. Regulation of the dynamic growth and shrinkage of microtubules gives cells their shape, allows cells to swim, and drives the separation of chromosomes. Parasites have developed intriguingly divergent biology, seemingly expanding upon and reinventing microtubule use in fascinating ways. These organisms affect life on the planet at scales that are often overlooked: there are likely more parasitic than free-living organisms on Earth, and they have a sizeable influence across ecosystems. As parasites can cause devastating diseases, this in turn drives evolutionary adaptations and species diversity. Parasites are varied, living in all environments and at all scales - from the tiny 2 μm single-celled Plasmodium merozoite that invades red blood cells to the 40 m long Tetragonoporus, a large intestinal tapeworm of whales. To survive in their various niches, parasites have undergone striking adaptations and developed complex life cycles, often involving two or more host species. This diversity is reflected at the cellular level, where unique molecular mechanisms, cytoskeletal structures and organellar compositions are found. Hence, the study of parasite cell biology provides a biological playground for understanding diversity and species diversification. It also facilitates the identification of specific targets to develop urgently needed therapeutics: for example, drugs targeting microtubules are used at large scale to treat intestinal worms and parasites that form tissue cysts in our livers and brains. Here, we discuss some of the curious microtubule arrays found in a small, select number of human-infecting, single-celled parasites of medical importance (Table 1). Our aim is to put a spotlight on distinctive molecular features in a field that promises exciting cell-biological discoveries with the potential for therapeutic breakthroughs.
Topics: Humans; Animals; Parasites; Ecosystem; Microtubules; Cytoskeleton; Acclimatization; Cetacea
PubMed: 37607476
DOI: 10.1016/j.cub.2023.07.001 -
Trends in Parasitology Jul 2023The mass production of insects is rapidly expanding globally, supporting multiple industrial needs. However, parasite infections in insect mass-production systems can... (Review)
Review
The mass production of insects is rapidly expanding globally, supporting multiple industrial needs. However, parasite infections in insect mass-production systems can lower productivity and can lead to devastating losses. High rearing densities and artificial environmental conditions in mass-rearing facilities affect the insect hosts as well as their parasites. Environmental conditions such as temperature, gases, light, vibration, and ionizing radiation can affect productivity in insect mass-production facilities by altering insect development and susceptibility to parasites. This review explores the recent literature on environment-host-parasite interactions with a specific focus on mass-reared insect species. Understanding these complex interactions offers opportunities to optimise environmental conditions for the prevention of infectious diseases in mass-reared insects.
Topics: Animals; Host-Parasite Interactions; Insecta; Parasites
PubMed: 37258342
DOI: 10.1016/j.pt.2023.04.007 -
Parasitology Research Dec 2023Leishmaniasis transmission cycles are maintained and sustained in nature by the complex crosstalk of the Leishmania parasite, sandfly vector, and the mammalian hosts... (Review)
Review
Leishmaniasis transmission cycles are maintained and sustained in nature by the complex crosstalk of the Leishmania parasite, sandfly vector, and the mammalian hosts (human, as well as zoonotic reservoirs). Regardless of the vast research on human host-parasite interaction, there persists a substantial knowledge gap on the parasite's development and modulation in the vector component. This review focuses on some of the intriguing aspects of the Leishmania-sandfly interface, beginning with the uptake of the intracellular amastigotes from an infected host to the development of the parasite within the sandfly's alimentary canal, followed by the transmission of infective metacyclic stages to another potential host. Upon ingestion of the parasite, the sandfly hosts an intricate repertoire of immune barriers, either to evade the parasite or to ensure its homeostatic coexistence with the vector gut microbiome. Sandfly salivary polypeptides and Leishmania exosomes are co-egested with the parasite inoculum during the infected vector bite. This has been attributed to the modulation of the parasite infection and subsequent clinical manifestation in the host. While human host-based studies strive to develop effective therapeutics, a greater understanding of the vector-parasite-microbiome and human host interactions could help us to identify the targets and to develop strategies for effectively preventing the transmission of leishmaniasis.
Topics: Animals; Humans; Leishmania; Psychodidae; Parasites; Phlebotomus; Leishmaniasis; Host-Parasite Interactions; Mammals
PubMed: 38052752
DOI: 10.1007/s00436-023-08043-7 -
Frontiers in Cellular and Infection... 2023
Topics: Animals; Parasites; Host-Parasite Interactions; Lipids
PubMed: 38045759
DOI: 10.3389/fcimb.2023.1334002 -
Evolution; International Journal of... Dec 2023Hyperparasites (species which parasitize other parasites) are common in natural populations, affecting many parasitic taxa, including: eukaryotic parasites; bacterial...
Hyperparasites (species which parasitize other parasites) are common in natural populations, affecting many parasitic taxa, including: eukaryotic parasites; bacterial and fungal pathogens. Hyperparasitism is therefore likely to shape the ecology and evolution of many host-parasite systems, representing a promising method for biocontrol (e.g., treating antimicrobial resistant infections). However, the eco-evolutionary consequences of hyperparasitism have received little attention. We use a host-parasite-hyperparasite model to explore how introducing a hyperparasite drives the evolution of parasite virulence, and what impact this has on the host population. We show when the introduction of a hyperparasite selects for higher or lower parasite virulence, and the changes in virulence experienced by the host population. Crucially, we show that variation in the direct effects of hyperparasites on virulence and transmission, and the probability of cotransmission, can lead to a previously unseen hysteresis effect, whereby small shifts in hyperparasite characteristics can lead to sudden shifts in parasite virulence. We also show that hyperparasites can induce diversification in parasite virulence, leading to the coexistence of high and low virulence strains. Our results show hyperparasites can have dramatic effects on the evolution of parasite virulence, and that the use of hyperparasites in biocontrol should be approached with caution.
Topics: Animals; Parasites; Virulence; Ecology; Biological Evolution; Host-Parasite Interactions
PubMed: 37778003
DOI: 10.1093/evolut/qpad178 -
Nature Microbiology Nov 2023Malaria-associated pathogenesis such as parasite invasion, egress, host cell remodelling and antigenic variation requires concerted action by many proteins, but the...
Malaria-associated pathogenesis such as parasite invasion, egress, host cell remodelling and antigenic variation requires concerted action by many proteins, but the molecular regulation is poorly understood. Here we have characterized an essential Plasmodium-specific Apicomplexan AP2 transcription factor in Plasmodium falciparum (PfAP2-P; pathogenesis) during the blood-stage development with two peaks of expression. An inducible knockout of gene function showed that PfAP2-P is essential for trophozoite development, and critical for var gene regulation, merozoite development and parasite egress. Chromatin immunoprecipitation sequencing data collected at timepoints matching the two peaks of pfap2-p expression demonstrate PfAP2-P binding to promoters of genes controlling trophozoite development, host cell remodelling, antigenic variation and pathogenicity. Single-cell RNA sequencing and fluorescence-activated cell sorting revealed de-repression of most var genes in Δpfap2-p parasites. Δpfap2-p parasites also overexpress early gametocyte marker genes, indicating a regulatory role in sexual stage conversion. We conclude that PfAP2-P is an essential upstream transcriptional regulator at two distinct stages of the intra-erythrocytic development cycle.
Topics: Animals; Parasites; Malaria; Gene Expression Regulation; Plasmodium falciparum; Plasmodium
PubMed: 37884813
DOI: 10.1038/s41564-023-01497-6 -
Parasites & Vectors Sep 2023
Topics: Animals; Parasites; Artificial Intelligence; Parasitic Diseases
PubMed: 37770977
DOI: 10.1186/s13071-023-05972-1