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Frontiers in Cellular and Infection... 2023The genus in Brazil includes 11 species and one subspecies, three of which are intermediate hosts of . Due to the recent evolution of this group, some species are...
INTRODUCTION
The genus in Brazil includes 11 species and one subspecies, three of which are intermediate hosts of . Due to the recent evolution of this group, some species are difficult to identify based on morphological characters, making the use of genetic markers necessary for species identification. This study aimed to evaluate the use of partial sequences of the cytochrome c oxidase I () gene for the identification of species using phylogenetic reconstruction and species delimitation algorithms. The study tested the use of DNA barcoding technique for species delimitation within the genus.
METHODS
DNA barcoding was performed by sequencing a partial region of the gene from specimens, and the sequences were analyzed using phylogenetic reconstruction and algorithms to delimit Operational Taxonomic Units (OTUs).
RESULTS
The study found that the use of the gene in the reconstruction of the phylogeny of the genus might be an alternative for understanding the evolution and dispersion of species. However, this marker alone is not enough to solve complex taxonomic problems within the genus. A total of 223 sequences were analyzed, 102 of which could be separated using the barcode gap, enabling the correct identification of seven taxa.
DISCUSSION
The study demonstrated that accurate mollusk identification is necessary for effective schistosomiasis control. The DNA barcoding methodology was found to be promising for accurate mollusk identification, which is crucial for concentrating schistosomiasis control efforts in places where it is needed.
Topics: Animals; Biomphalaria; Phylogeny; DNA Barcoding, Taxonomic; DNA; Schistosoma mansoni
PubMed: 37168391
DOI: 10.3389/fcimb.2023.1167787 -
International Journal of Environmental... Jan 2017Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles... (Review)
Review
Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles in influencing the life history traits of the intermediate hosts (IHs). This review focused on studies and disease models that evaluate the potential effect of temperature rise on the ecology of IH snails and the development of parasites within them. The main focus was on IH snails of schistosome parasites that cause schistosomiasis in humans. A literature search was conducted on Google Scholar, EBSCOhost and PubMed databases using predefined medical subject heading terms, Boolean operators and truncation symbols in combinations with direct key words. The final synthesis included nineteen published articles. The studies reviewed indicated that temperature rise may alter the distribution, optimal conditions for breeding, growth and survival of IH snails which may eventually increase the spread and/or transmission of schistosomiasis. The literature also confirmed that the life history traits of IH snails and their interaction with the schistosome parasites are affected by temperature and hence a change in climate may have profound outcomes on the population size of snails, parasite density and disease epidemiology. We concluded that understanding the impact of temperature on the growth, fecundity and survival of IH snails may broaden the knowledge on the possible effects of climate change and hence inform schistosomiasis control programmes.
Topics: Animals; Biomphalaria; Bulinus; Climate Change; Disease Vectors; Fertility; Humans; Population Density; Schistosomiasis; Temperature
PubMed: 28098789
DOI: 10.3390/ijerph14010080 -
Memorias Do Instituto Oswaldo Cruz Sep 2006As well as malaria and yellow fever, schistosomiasis is one of the main endemic diseases associated to environments which suffered some impact related to the development...
As well as malaria and yellow fever, schistosomiasis is one of the main endemic diseases associated to environments which suffered some impact related to the development of great economic projects, as for example the construction of hydroelectric power stations. Aiming to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area which suffered impact from the Manso hydroelectric power station a survey was performed during the period of 2002 to 2003 and revealed the occurrence of populations of Biomphalaria amazonica and Biomphalaria occidentalis. Studies on parasite-mollusc compatibility were undertaken using five B. amazonica colonies (Barão de Melgaço, Poconé, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Manso and Casca rivers), and four B. occidentalis colonies (Cuiabá, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Agua Fria district and Casca river) were exposed to miracidia of Schistosoma mansoni. Of 257 snails of B. amazonica used, 17 became infected (infection index of 6.61%) and all specimens of B. occidentalis proved unsusceptible. According to the strains used, of the 158 snails exposed to BH miracidia, 6 became infected (3.79%); of the 44 exposed to SJ miracidia, 6 became infected (13.63%); and of the 55 snails of B. amazonica exposed to EC miracidia, 5 became infected (9.09%). These results point out the low possibility of introduction of schistosomiasis in those areas, but we believe it can not be discarded as due the presence of B. amazonica.
Topics: Animals; Biomphalaria; Brazil; Disease Vectors; Fresh Water; Host-Parasite Interactions; Humans; Schistosoma mansoni; Schistosomiasis mansoni; Species Specificity
PubMed: 17308775
DOI: 10.1590/s0074-02762006000900036 -
PLoS Neglected Tropical Diseases Feb 2022Seawater intrusion associated with decreasing groundwater levels and rising seawater levels may affect freshwater species and their parasites. While brackish water...
Seawater intrusion associated with decreasing groundwater levels and rising seawater levels may affect freshwater species and their parasites. While brackish water certainly impacts freshwater systems globally, its impact on disease transmission is largely unknown. This study examined the effect of artificial seawater on host-parasite interactions using a freshwater snail host, Biomphalaria alexandrina, and the human trematode parasite Schistosoma mansoni. To evaluate the impact of increasing salinity on disease transmission four variables were analyzed: snail survival, snail reproduction, infection prevalence, and the survival of the parasite infective stage (cercariae). We found a decrease in snail survival, snail egg mass production, and snail infection prevalence as salinity increases. However, cercarial survival peaked at an intermediate salinity value. Our results suggest that seawater intrusion into freshwaters has the potential to decrease schistosome transmission to humans.
Topics: Animals; Biomphalaria; Cercaria; Ecosystem; Host-Parasite Interactions; Reproduction; Schistosoma mansoni; Seawater
PubMed: 35202408
DOI: 10.1371/journal.pntd.0009524 -
PeerJ 2022is a snail intermediate host for , a trematode responsible for human schistosomiasis. BS90 is one of the most well studied strains of owing to its high resistance to...
BACKGROUND
is a snail intermediate host for , a trematode responsible for human schistosomiasis. BS90 is one of the most well studied strains of owing to its high resistance to infection by most strains of . An F2 mapping study from 1999 identified two RAPD markers that associated with what appeared to be single-locus, dominant resistance by the BS90 population relative to the susceptible M-line population. One marker cannot be mapped, but the other, , maps to within 5 Mb of , a region we recently showed has a very large effect on resistance within another snail population challenged by the same strain of parasite (PR1). Here we tested the hypothesis that the region contains the causal gene/s that explain the iconic resistance of BS90 snails.
METHODS
We used marker-assisted backcrossing to drive the BS90 version of the PTC2 region (+/-~1 Mb on either side) into an M-line (susceptible strain) genetic background, and the M-line version into a BS90 genetic background. We challenged the offspring with PR1-strain schistosomes and tested for effects of allelic variation in the region in a common genetic background.
RESULTS
Relative to M-line haplotypes, the BS90 haplotype actually confers enhanced susceptibility. So we reject our original hypothesis. One possible explanation for our result was that the causal gene linked to is near, but not in the block that we introgressed into each line. So we used an F2 cross to independently test the effects of the and regions in a randomized genetic background. We confirmed that the BS90 haplotype confers increased susceptibility, and we see a similar, although non-significant effect at . We discuss possible reasons why our results differed so dramatically from those of the 1999 study. We also present Pacbio assemblies of the and flanking region in BS90 and M-line, compare with previously published haplotypes, and discuss candidate genes that might be behind the enhanced susceptibility of the BS90 haplotype.
Topics: Animals; Humans; Schistosoma mansoni; Biomphalaria; Random Amplified Polymorphic DNA Technique; Host-Parasite Interactions; Snails; Genotype
PubMed: 36117535
DOI: 10.7717/peerj.13971 -
General and Comparative Endocrinology Sep 2019Peptide hormones and neurotransmitters involved in reproduction and growth have been studied extensively in certain gastropod molluscs, such as Lymnaea stagnalis and...
Peptide hormones and neurotransmitters involved in reproduction and growth have been studied extensively in certain gastropod molluscs, such as Lymnaea stagnalis and Aplysia californica. The present study employs antisera that have been used to study peptidergic neurons in those species to probe the central nervous system of another gastropod, Biomphalaria alexandrina, an intermediate host of the parasitic trematode that causes schistosomiasis in humans. Whole mount preparations of central ganglia were stained immunohistochemically, and several populations of neurons appeared to be homologous to those forming the neuroendocrine axis that has been previously described in L. stagnalis. These cells include the caudodorsal cells and the light green and canopy cells, which produce hormones that regulate ovulation and growth, respectively. Other populations of cells containing APGWamide, FMRFamide and/or related peptides are consistent with ones that innervate the penis in L. stagnalis and other gastropods. Identification of neurons that might be responsible for the control of reproduction and growth in Biomphalaria provides an important initial step toward the development of novel methods of disease control and pest management directed toward reducing snail populations.
Topics: Animals; Biomphalaria; Central Nervous System; Immunohistochemistry; Insulin; Neurons; Neuropeptides; Neurosecretory Systems; Neurotransmitter Agents; Reproduction
PubMed: 30923005
DOI: 10.1016/j.ygcen.2019.03.017 -
Experimental Parasitology Nov 2009Schistosomes develop successfully in susceptible snails but are encapsulated and killed in resistant ones. Mechanism(s) shaping these outcomes involves the parasites...
Schistosomes develop successfully in susceptible snails but are encapsulated and killed in resistant ones. Mechanism(s) shaping these outcomes involves the parasites ability to evade the snail's defenses. RNA analysis from resistant (BS-90), non-susceptible (LAC2) and susceptible (NMRI) juvenile Biomphalaria glabrata to Schistosoma mansoni revealed that stress-related genes, heat shock protein 70 (Hsp 70) and reverse transcriptase (RT), were dramatically co-induced early in susceptible snails, but not in resistant/non-susceptible ones. These transcripts were, however, down regulated upon exposure to irradiated parasites although penetration behavior of irradiated vs. normal parasites were the same, indicating that Hsp 70 and RT regulation was elicited by infection and not injury. Understanding molecular events involved in stress response transcriptional regulation of Hsp 70 in juvenile snails could pave a way towards the identification of genes involved in schistosome/snail interactions.
Topics: Animals; Biomphalaria; Down-Regulation; Gamma Rays; Gene Expression; HSP70 Heat-Shock Proteins; RNA-Directed DNA Polymerase; Reverse Transcriptase Polymerase Chain Reaction; Schistosoma mansoni; Transcriptional Activation
PubMed: 19660454
DOI: 10.1016/j.exppara.2009.07.015 -
PLoS Neglected Tropical Diseases Jun 2023The neglected tropical disease schistosomiasis impacts over 700 million people globally. Schistosoma mansoni, the trematode parasite that causes the most common type of...
The neglected tropical disease schistosomiasis impacts over 700 million people globally. Schistosoma mansoni, the trematode parasite that causes the most common type of schistosomiasis, requires planorbid pond snails of the genus Biomphalaria to support its larval development and transformation to the cercarial form that can infect humans. A greater understanding of neural signaling systems that are specific to the Biomphalaria intermediate host could lead to novel strategies for parasite or snail control. This study examined a Biomphalaria glabrata neural channel that is gated by the neuropeptide FMRF-NH2. The Biomphalaria glabrata FMRF-NH2 gated sodium channel (Bgl-FaNaC) amino acid sequence was highly conserved with FaNaCs found in related gastropods, especially the planorbid Planorbella trivolvis (91% sequence identity). In common with the P. trivolvis FaNaC, the B. glabrata channel exhibited a low affinity (EC50: 3 x 10-4 M) and high specificity for the FMRF-NH2 agonist. Its expression in the central nervous system, detected with immunohistochemistry and in situ hybridization, was widespread, with the protein localized mainly to neuronal fibers and the mRNA confined to cell bodies. Colocalization of the Bgl-FaNaC message with its FMRF-NH2 agonist precursor occurred in some neurons associated with male mating behavior. At the mRNA level, Bgl-FaNaC expression was decreased at 20 and 35 days post infection (dpi) by S. mansoni. Increased expression of the transcript encoding the FMRF-NH2 agonist at 35 dpi was proposed to reflect a compensatory response to decreased receptor levels. Altered FMRF-NH2 signaling could be vital for parasite proliferation in its intermediate host and may therefore present innovative opportunities for snail control.
Topics: Animals; Male; Humans; Schistosoma mansoni; Biomphalaria; FMRFamide; Schistosomiasis; Trematoda; Central Nervous System; Schistosomiasis mansoni; Host-Parasite Interactions
PubMed: 37352363
DOI: 10.1371/journal.pntd.0011249 -
PloS One 2014Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and...
Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and size. They are enveloped by a lamina of extracellular matrix. Their most characteristic feature is the "slit apparatus", local invaginations of the plasma membrane bridged by cytoplasmic bars, forming slits of ca. 20 nm width. A slit diaphragm creates a molecular sieve with permeation holes of 20×20 nm. In blue-blooded gastropods, rhogocytes synthesize and secrete the respiratory protein hemocyanin, and it has been proposed-though not proven-that in the rare red-blooded snail species they might synthesize and secrete the hemoglobin. However, the cellular secretion pathway for respiratory proteins, and the functional role(s) of the enigmatic rhogocyte slit apparatus are still unclear. Additional functions for rhogocytes have been proposed, notably a role in protein uptake and degradation, and in heavy metal detoxification. Here we provide new structural and functional information on the rhogocytes of the red-blooded freshwater snail Biomphalaria glabrata. By in situ hybridization of mantle tissues, we prove that rhogocytes indeed synthesize hemoglobin. By electron tomography, the first three dimensional (3D) reconstructions of the slit apparatus are provided, showing detail of highly dense material in the cytoplasmic bars close to the slits. By immunogold labelling, we collected evidence that a major component of this material is actin. By genome databank mining, the complete sequence of a B. glabrata nephrin was obtained, and localized to the rhogocytes by immunofluorescence microscopy. The presence of both proteins fit the ultrastructure-based hypothesis that rhogocytes are related to mammalian podocytes and insect nephrocytes. Reactions of the rhogocytes to deprivation of food and cadmium toxification are also documented, and a possible secretion pathway of newly synthesized respiratory proteins through the slit apparatus is discussed.
Topics: Amino Acid Sequence; Animals; Biomphalaria; Cadmium; Cell Membrane; Electron Microscope Tomography; Imaging, Three-Dimensional; Membrane Proteins; Molecular Sequence Data; Stress, Physiological
PubMed: 24971744
DOI: 10.1371/journal.pone.0101078 -
Experimental Parasitology Dec 2016Angiostrongylus cantonensis is considered the main agent responsible for human eosinophilic meningoencephalitis. This parasite has low specificity for mollusk hosts and...
The influence of Angiostrongylus cantonensis (Nematoda, Metastrongylidae) infection on the aerobic metabolism of Biomphalaria straminea and Biomphalaria tenagophila (Mollusca, Gastropoda).
Angiostrongylus cantonensis is considered the main agent responsible for human eosinophilic meningoencephalitis. This parasite has low specificity for mollusk hosts and it can also use aquatic snails as auxiliary hosts. Studies based on the metabolic profile of Biomphalaria spp. infected by A. cantonensis have been conducted to observe parasite-host interactions. In the present study, the glucose content in the hemolymph and glycogen content in the digestive gland and cephalopedal mass of Biomphalaria tenagophila and Biomphalaria straminea experimentally infected by A. cantonensis were evaluated, along with the activity of LDH. The snails were dissected from 6 to 21days after infection to collect the hemolymph and separate the tissues. Decreases of 96% and 6.4% in the glucose content triggered a transition from aerobic to anaerobic metabolism in the two infected snail species, B. straminea and B. tenagophila, respectively. That finding was confirmed by high-performance liquid chromatography. These results indicate that when infected, these snails are able to change their metabolic profile, suggesting a strategy to maintain their homeostatic balance.
Topics: Aerobiosis; Angiostrongylus cantonensis; Animals; Biomphalaria; Chromatography, High Pressure Liquid; Glucose; Glycogen; Hemolymph; Homeostasis; Host-Parasite Interactions; L-Lactate Dehydrogenase
PubMed: 27743973
DOI: 10.1016/j.exppara.2016.10.010