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1.
Parasitology ; 151(3): 300-308, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38212980

RESUMO

A 30 years long data series on the infection dynamics of European eel (Anguilla anguilla L.) with the non-native invasive nematode Anguillicola crassus Kuwahara, Niimi & Hagaki, 1974 is presented. Parasite burden was evaluated for 30 years in inland and coastal waters in Mecklenburg-Western Pomerania from 1991 to 2020. The total prevalence, mean intensity and damage status of the swim bladders were very high during the first decade (1991­2000), and significantly decreased in both marine and freshwater eel populations in the following decades (2001­2010, 2011­2020). The parasite intensity of eels in coastal waters was significantly lower compared with the freshwater systems (61.3% vs 79.5% in the first decade), indicating the vulnerability of the parasites to brackish water conditions and the fact that the life cycle of A. crassus cannot be completed under high saline conditions. Eel caught in the western part of the Baltic Sea (west of Darss sill) had the lowest mean infection (51.8% in first decade) compared to the eastern part with 63.8%. Thus, besides different infection patterns caused by the environmental conditions, a temporal trend towards a reduced parasite intensity and a more balanced parasite­host relationship developed in the 30 years of interaction after the first invasion. Possible reasons and mechanisms for the observed trends in parasite­host interactions are discussed.


Assuntos
Anguilla , Dracunculoidea , Doenças dos Peixes , Animais , Anguilla/parasitologia , Sacos Aéreos/parasitologia , Estágios do Ciclo de Vida , Alemanha/epidemiologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia
2.
Parasitol Res ; 123(6): 254, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922478

RESUMO

The Americas hold the greatest bird diversity worldwide. Likewise, ectoparasite diversity is remarkable, including ticks of the Argasidae and Ixodidae families - commonly associated with birds. Considering that ticks have potential health implications for humans, animals, and ecosystems, we conducted a systematic review to evaluate the effects of bioclimatic, geographic variables, and bird species richness on tick infestation on wild birds across the Americas. We identified 72 articles that met our inclusion criteria and provided data on tick prevalence in wild birds. Using Generalized Additive Models, we assessed the effect of environmental factors, such as habitat type, climatic conditions, bird species richness, and geographic location, on tick infestation. Our findings show that most bird infestation case studies involved immature ticks, such as larvae or nymphs, while adult ticks represented only 13% of case studies. We found birds infested by ticks of the genera Amblyomma (68%), Ixodes (22%), Haemaphysalis (5%), Dermacentor (1%), and Rhipicephalus (0.8%) in twelve countries across the Americas. Our findings revealed that temperature variation and bird species richness were negatively associated with tick infestation, which also varied with geographic location, increasing in mid-latitudes but declining in extreme latitudes. Our results highlight the importance of understanding how environmental and bird community factors influence tick infestation in wild birds across the Americas and the dynamics of tick-borne diseases and their impact on biodiversity.


Assuntos
Doenças das Aves , Aves , Infestações por Carrapato , Animais , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Aves/parasitologia , América/epidemiologia , Doenças das Aves/parasitologia , Doenças das Aves/epidemiologia , Animais Selvagens/parasitologia , Ecossistema , Carrapatos/fisiologia , Carrapatos/classificação , Biodiversidade , Meio Ambiente , Prevalência
3.
Exp Parasitol ; 245: 108443, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36526003

RESUMO

Breast cancer is considered the type of cancer that most affects women in the world. The triple negative breast cancer is considered aggressive with poor prognosis. In the 1930s Russian researchers observed that T. cruzi has tropism for tumor cells. Since then, this research field has been subject of a numerous of researches. Here, we proposed to investigate the impact of T. cruzi infection on proliferation and migration of triple negative breast cancer cell line (MDA-MB-231). T. cruzi showed high invasion and multiplication rate in MDA-MB-231 cell line. The infection promoted the multiplication of MDA-MB-231 cell, continuous cell lysis throughout of days of in vitro infection and impaired MDA-MB-231 cell migration. Taken together, these results demonstrated the high susceptibility of MDA-MB-231 cell to T. cruzi and suggested that molecules from T. cruzi may impair host cell migration with potential use to avoid metastasis.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Movimento Celular
4.
J Exp Bot ; 73(4): 1204-1221, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-34849736

RESUMO

The European mistletoe (Viscum album) is an epiphytic hemiparasite that attaches to its host by an endophytic system. Two aspects are essential for its survival: the structural integrity of the host-parasite interface must be maintained during host growth and the functional integrity of the interface must be maintained during ontogeny and under mechanical stress. We investigated the mechanical properties of the mistletoe-host interaction. Intact and sliced mistletoe-host samples, with host wood as reference, were subjected to tensile tests up to failure. We quantified the rough fractured surface by digital microscopy and analysed local surface strains by digital image correlation. Tensile strength and deformation energy were independent of mistletoe age but exhibited markedly lower values than host wood samples. Cracks initiated at sites with a major strain of about 30%, especially along the mistletoe-host interface. The risk of sudden failure was counteracted by various sinkers and a lignification gradient that smooths the differences in the mechanical properties between the two species. Our results improve the understanding of the key mechanical characteristics of the host-mistletoe interface and show that the mechanical connection between the mistletoe and its host is age-independent. Thus, functional and structural integrity is ensured over the lifetime of the mistletoe.


Assuntos
Viscum album , Fenômenos Biomecânicos , Interações Hospedeiro-Parasita , Viscum album/química , Madeira
5.
Parasite Immunol ; 44(12): e12950, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36104299

RESUMO

Haemonchus contortus (H. contortus) has caused a huge impact on the animal husbandry economy in the world's tropical and subtropical regions. Innate immunity is the first-line of host defence. The host recognizes pathogen-associated molecular patterns (PAMPs) through a variety of pattern recognition receptors (PRRs) and activates downstream signalling pathways to resist pathogens invasion. Therefore, elucidating the immune interaction between host and pathogen is key to understanding how the host resists the pathogen. We identified 1516 protein-protein interactions (PPIs) between goat innate immune signal pathway proteins and H. contortus excretory-secretory proteins (ESPs) by Recombination-based "Library vs. Library" yeast two-hybrid system (RLL-Y2H) and constructed the PPIs network. Among them, the NLR and IL-17 signalling pathways have the most protein interactions. And there were more interaction proteins between NOD1 and MUC5AC proteins in the pathways. Combined with the differentially expressed genes (DEGs) of susceptible and resistant goats identified in the preliminary work of our laboratory, we selected the intersection genes to construct the PPIs network, and TRAF2 appeared as a key protein of goat innate immune signalling pathway. We initially studied the PPIs between goat and H. contortus ESPs, which provides valuable information for better understanding the immune interaction between the goats and the H. contortus.


Assuntos
Doenças das Cabras , Hemoncose , Haemonchus , Animais , Hemoncose/veterinária , Cabras , Imunidade Inata , Transdução de Sinais
6.
Parasitology ; 149(13): 1667-1678, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36200511

RESUMO

Transmission mode is a key factor that influences host­parasite coevolution. Vector-borne pathogens are among the most important disease agents for humans and wildlife due to their broad distribution, high diversity, prevalence and lethality. They comprise some of the most important and widespread human pathogens, such as yellow fever, leishmania and malaria. Vector-borne parasites (in this review, those transmitted by blood-feeding Diptera) follow unique transmission routes towards their vertebrate hosts. Consequently, each part of this tri-partite (i.e. parasite, vector and host) interaction can influence co- and counter-evolutionary pressures among antagonists. This mode of transmission may favour the evolution of greater virulence to the vertebrate host; however, pathogen­vector interactions can also have a broad spectrum of fitness costs to the insect vector. To complete their life cycle, vector-borne pathogens must overcome immune responses from 2 unrelated organisms, since they can activate responses in both vertebrate and invertebrate hosts, possibly creating a trade-off between investments against both types of immunity. Here, we assess how dipteran vector-borne transmission shapes the evolution of hosts, vectors and the pathogens themselves. Hosts, vectors and pathogens co-evolve together in a constant antagonistic arms race with each participant's primary goal being to maximize its performance and fitness.


Assuntos
Leishmania , Malária , Animais , Humanos , Insetos Vetores/parasitologia , Estágios do Ciclo de Vida , Virulência
7.
Parasitology ; 149(9): 1173-1178, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35570667

RESUMO

The cestode Schistocephalus solidus is a common parasite in freshwater threespine stickleback populations, imposing strong fitness costs on their hosts. Given this, it is surprising how little is known about the timing and development of infections in natural stickleback populations. Previous work showed that young-of-year stickleback can get infected shortly after hatching. We extended this observation by comparing infection prevalence of young-of-year stickleback from 3 Alaskan populations (Walby, Cornelius and Wolf lakes) over 2 successive cohorts (2018/19 and 2019/20). We observed strong variation between sampling years (2018 vs 2019 vs 2020), stickleback age groups (young-of-year vs 1-year-old) and sampling populations.


Assuntos
Infecções por Cestoides , Doenças dos Peixes , Smegmamorpha , Alaska/epidemiologia , Animais , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/veterinária , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Lagos/parasitologia , Smegmamorpha/parasitologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-35589083

RESUMO

Studies which quantify the influence of abiotic factors on physiological variation are paramount to comprehend organismal responses to diverse environments. We studied three physiological aspects of metabolism in two sympatric and ecologically similar European lizard species, Podarcis muralis and Iberolacerta horvathi, across an 830-m elevational gradient. We collected blood samples and tail tips from adult lizards, which were analyzed for parasitemia, hemoglobin concentration, potential metabolic activity and catalase activity. Hemoglobin concentration was higher in males than females and it increased across elevation in one of the studied species - P. muralis. Parasitemia was not an important predictor of the variation in hemoglobin concentration, which suggests that blood parasites do not constraint the aerobic capacity of the lizards. On the other hand, catalase activity reflected increased antioxidant activity in the presence of higher parasitemia, possibly acting as an adaptive mechanism to reduce oxidative stress during immune activation. Potential metabolic activity, as a proxy for maximum respiratory enzymatic capacity, did not differ between species or sexes nor was it affected by elevation or levels of parasitemia. The results provide insight into the relationships between physiological, biotic, and environmental traits in sympatric lizards.


Assuntos
Lagartos , Animais , Antioxidantes , Catalase , Feminino , Hemoglobinas , Lagartos/fisiologia , Masculino , Parasitemia/parasitologia
9.
Parasitology ; 147(9): 1008-1018, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32338227

RESUMO

Giardia lamblia is a causative agent of persistent diarrhoea widespread in regions with low hygienic standards. Laboratory research is based on cloned lines issuing from various patient isolates typed in the late 1980s and 90s using restriction analysis and serology. In the present study, we compared the well-characterized strain WBC6 with another clone of the parent WB isolate termed WBA1 and with a clone from another isolate, GS/M-83-H7, using shotgun mass spectrometry proteomics. We identified 398 proteins differentially expressed between the GS and both WB isolates and 97 proteins differentially expressed between the two WB isolates. We investigated the expression levels of the predominant variant-specific surface proteins (VSPs) in each clone and matched the previously described major VSPs of each strain to the corresponding open reading frame sequences identified by whole-genome sequencing efforts. Furthermore, since the original WB isolate comes from a patient treated with metronidazole, we compared the susceptibilities of the strains to nitro compounds, as well the expression levels of enzymes involved in nitro reduction and on the corresponding enzyme activities and found distinct differences between the three strains.


Assuntos
Variação Antigênica/genética , Giardia/genética , Proteoma/imunologia , Proteínas de Protozoários/imunologia , Genômica , Giardia/imunologia , Proteômica
10.
Parasitol Res ; 119(7): 2337-2342, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32500371

RESUMO

Philornis flies Meinert (Diptera: Muscidae) have been documented parasitizing over 250 bird species, some of which are endemic species threatened with extinction. Philornis parasitism is hypothesized to affect nestlings disproportionately more than adult birds because limited mobility and exposed skin of nestlings increase their vulnerability to parasitism. We used a comprehensive literature review and our recent fieldwork in the Dominican Republic, Puerto Rico, and Grenada to challenge the idea that parasitism by subcutaneous Philornis species is a phenomenon primarily found in nestlings, a fact that has not been quantified to date. Of the 265 reviewed publications, 125 (49%) reported incidences of parasitism by subcutaneous Philornis, but only 12 included the sampling of adult breeding birds. Nine of these publications (75%) reported Philornis parasitism in adults of ten bird species. During fieldwork in the Dominican Republic, Puerto Rico, and Grenada, we documented 14 instances of parasitism of adult birds of seven avian species. From literature review and fieldwork, adults of at least fifteen bird species across 12 families and four orders of birds were parasitized by at least five Philornis species. In both the published literature and fieldwork, incidences of parasitism of adult birds occurred predominantly in females and was frequently associated with incubation. Although our findings indicate that Philornis parasitism of adult birds is more common than widely presumed, parasite prevalence is still greater in nestlings. In the future, we recommend surveys of adult birds to better understand host-Philornis relationships across life stages. This information may be essential for the development of effective control measures of Philornis to ensure the long-term protection of bird species of conservation concern.


Assuntos
Aves/parasitologia , Muscidae/fisiologia , Animais , Aves/classificação , Feminino , Incidência , Larva/classificação , Larva/fisiologia , Masculino , Muscidae/classificação , Comportamento de Nidação , Prevalência , Índias Ocidentais/epidemiologia
11.
Cell Microbiol ; 20(11): e12887, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29968354

RESUMO

Toxoplasma gondii is an obligate intracellular parasite that infects up to 30% of humans worldwide. It can lead to severe diseases particularly in individuals with immature or defective immune responses. Control of T. gondii relies on the IFN-γ-induced signal transducer and activator of transcription-1 (STAT1) pathway. T. gondii, however, largely inactivates STAT1-mediated gene transcription by T. gondii inhibitor of STAT1-dependent transcription (TgIST), a parasite effector protein binding to STAT1. Here, we have analysed requirements of STAT1 to bind TgIST and characterised downstream effects on STAT1 signalling. TgIST bound to STAT1 dimers but more efficiently assembled with STAT1 tetramers, which are essential for effective IFN-γ responsiveness. Such binding was abrogated in N-terminal, but not C-terminal deletion mutants of STAT1. Furthermore, TgIST did not bind to the STAT1F77A substitution mutant that cannot form STAT1 tetramers, resulting in a complete unresponsiveness of parasite-infected STAT1F77A -expressing cells to IFN-γ. Remarkably, binding of TgIST considerably increased the affinity of the aberrant STAT1 tetramers for DNA consensus sequence binding motifs and even enabled binding to nonconsensus sequences. Consistent with the increased DNA binding, STAT1 from parasite-infected cells remained phosphorylated at Tyr701 and Ser727 and was retained within the nucleus in a DNA-bound state. The sustained and promiscuous binding activity particularly of STAT1 tetramers to unspecific DNA sites lacking a consensus STAT1-binding motif is an as yet unrecognised mechanism contributing to the defective IFN-γ-mediated signalling in T. gondii-infected cells.


Assuntos
DNA/metabolismo , Proteínas de Protozoários/metabolismo , Fator de Transcrição STAT1/metabolismo , Toxoplasma/metabolismo , Animais , Núcleo Celular/metabolismo , Interações Hospedeiro-Parasita/efeitos dos fármacos , Interações Hospedeiro-Parasita/fisiologia , Interferon gama/metabolismo , Interferon gama/farmacologia , Camundongos , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Fosforilação , Multimerização Proteica , Células RAW 264.7 , Fator de Transcrição STAT1/genética , Serina/metabolismo , Toxoplasma/patogenicidade , Toxoplasmose/metabolismo , Toxoplasmose/parasitologia , Tirosina/metabolismo
12.
Exp Parasitol ; 201: 11-20, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31022392

RESUMO

The characteristics of parasitic infections are often tied to host behavior. Although most studies have investigated definitive hosts, intermediate hosts can also play a role in shaping the distribution and accumulation of parasites. This is particularly relevant in larval stages, where intermediate host's behavior could potentially interfere in the molecules secreted by the parasite into the next host during infection. To investigate this hypothesis, we used a proteomic approach to analyze excretion/secretion products (ESP) from Fasciola hepatica newly excysted juveniles (NEJ) derived from two intermediate host species, Lymnaea viatrix and Pseudosuccinea columella. The two analyzed proteomes showed differences in identity, abundance, and functional classification of the proteins. This observation could be due to differences in the biological cycle of the parasite in the host, environmental aspects, and/or host-dependent factors. Categories such as protein modification machinery, protease inhibitors, signal transduction, and cysteine-rich proteins showed different abundance between samples. More specifically, differences in abundance of individual proteins such as peptidyl-prolyl cis-trans isomerase, thioredoxin, cathepsin B, cathepsin L, and Kunitz-type inhibitors were identified. Based on the differences identified between NEJ ESP samples, we can conclude that the intermediate host is a factor influencing the proteomic profile of ESP in F. hepatica.


Assuntos
Fasciola hepatica/metabolismo , Proteínas de Helminto/metabolismo , Lymnaea/parasitologia , Proteômica , Caramujos/parasitologia , Animais , Anidrases Carbônicas/classificação , Anidrases Carbônicas/metabolismo , Proteínas de Helminto/classificação , Larva/metabolismo , Peptídeo Hidrolases/classificação , Peptídeo Hidrolases/metabolismo , Peroxirredoxinas/classificação , Peroxirredoxinas/metabolismo , Inibidores de Proteases/classificação , Inibidores de Proteases/metabolismo , Receptores de Superfície Celular/classificação , Receptores de Superfície Celular/metabolismo
13.
Parasitol Res ; 118(12): 3429-3441, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667591

RESUMO

The parasite Cryptosporidium parvum Tyzzer 1912 destroys parts of the intestinal brush border membrane which is important for the uptake of nutrients like glucose. In this study, glucose transport mechanisms of the host cells (IPEC-J2 cells) infected by C. parvum were investigated. The mRNA expression levels of glucose transporters (GLUT) 1 and 2 and Na+-coupled glucose transporter (SGLT) 1 were compared in infected and uninfected cells over an infection time of 24-96 h by RT-qPCR. Furthermore, the protein expression of SGLT 1 and GLUT 2 was quantified in western blot studies. While the protein expression of SGLT 1 was not altered in infected cells, mRNA expression of SGLT 1 and GLUT 1 was significantly increased 24 h p. i. and decreased 96 h p. i. The mRNA expression of GLUT 2 was significantly decreased 24 h, 72 h, and 96 h p. i. and also correlated significantly with the infection dose at 72 h p. i. In contrast to that, the protein expression of GLUT 2 was significantly increased 48 h p. i., associated with a significantly higher intracellular glucose level in infected cells compared with control cells at that time point of infection. This points to an adaptation of the host cells' glucose uptake taking place in the acute phase of the infection. A better understanding of these molecular mechanisms following a C. parvum infection may probably lead to an improvement of therapy strategies in the future.


Assuntos
Criptosporidiose/patologia , Cryptosporidium parvum/metabolismo , Enterócitos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador 1 de Glucose-Sódio/metabolismo , Animais , Transporte Biológico , Linhagem Celular , Criptosporidiose/parasitologia , Enterócitos/parasitologia , Glucose/metabolismo , Suínos
14.
Immunol Cell Biol ; 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29808496

RESUMO

Helminth parasites (worms) have evolved a vast array of strategies to manipulate their vertebrate hosts. Extracellular vesicles (EVs) are secreted by all helminth species investigated thus far, and their salient roles in parasite-host interactions are being revealed. Parasite EVs directly interact with various cell types from their hosts, including immune cells, and roles for their molecular cargo in both regulation and promotion of inflammation in the host have been reported. Despite the growing body of literature on helminth EVs, limited availability of genetic manipulation tools for helminth research has precluded detailed investigation of specific molecular interactions between parasite EVs and host target cells. Here, we review the current state of the field and discuss innovative strategies targeting helminth EVs for the discovery and development of new therapeutic strategies, placing particular emphasis on both anti-helminth vaccines and EV small RNAs for treating noninfectious inflammatory diseases.

15.
Parasitology ; 145(6): 814-821, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29183410

RESUMO

Invasive parasites can spill over to new hosts in invaded ecosystems with often unpredictable trophic relationships in the newly arising parasite-host interactions. In European seas, the intestinal copepod Mytilicola orientalis was co-introduced with Pacific oysters (Magallana gigas) and spilled over to native blue mussels (Mytilus edulis), with negative impacts on the condition of infected mussels. However, whether the parasite feeds on host tissue and/or stomach contents is yet unknown. To answer this question, we performed a stable isotope analysis in which we included mussel host tissue and the primary food sources of the mussels, microphytobenthos (MPB) and particulate organic matter (POM). The copepods were slightly enriched in δ15N (mean Δ15N ± s.d.; 1·22 ± 0·58‰) and δ13C (Δ13C 0·25 ± 0·32‰) with respect to their host. Stable isotope mixing models using a range of trophic fractionation factors indicated that host tissue was the main food resource with consistent additional contributions of MPB and POM. These results suggest that the trophic relationship of the invasive copepod with its mussel host is parasitic as well as commensalistic. Stable isotope studies such as this one may be a useful tool to unravel trophic relationships in new parasite-host associations in the course of invasions.


Assuntos
Copépodes/fisiologia , Interações Hospedeiro-Parasita , Mytilus edulis/fisiologia , Simbiose , Animais , Ecossistema , Comportamento Alimentar , Cadeia Alimentar , Marcação por Isótopo/métodos , Mytilus edulis/parasitologia
16.
Parasitology ; 144(13): 1695-1707, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28697819

RESUMO

Cystatins are small, phylogenetically conserved proteins that are tight-binding inhibitors of cysteine proteinases. The liver fluke Fasciola hepatica uses a diverse set of cysteine proteinases of the papain superfamily for host invasion, immune evasion and nutrition, but little is known about the regulation of these enzymes. The aim of this work is to characterize the cystatin repertoire of F. hepatica. For this purpose, we first surveyed the available sequence databases, identifying three different F. hepatica single-domain cystatins. In agreement with the in silico predictions, at least three small proteins with cysteine proteinase binding activity were identified. Phylogenetic analyses showed that the three cystatins (named FhStf-1, -2 and -3) are members of the I25A subfamily (stefins). Whereas FhStf-1 grouped with classical stefins, FhStf-2 and 3 fell in a divergent stefin subgroup unusually featuring signal peptides. Recombinant rFhStf-1, -2 and -3 had potent inhibitory activity against F. hepatica cathepsin L cysteine proteinases but differed in their capacity to inhibit mammalian cathepsin B, L and C. FhStf-1 was localized in the F. hepatica reproductive organs (testes and ovary), and at the surface lamella of the adult gut, where it may regulate cysteine proteinases related with reproduction and digestion, respectively. FhStf-1 was also detected among F. hepatica excretion-secretion (E/S) products of adult flukes. This suggests that it is secreted by non-classical secretory pathway and that it may interact with host lysosomal cysteine proteinases.


Assuntos
Cistatinas/genética , Inibidores de Cisteína Proteinase/farmacologia , Fasciola hepatica/genética , Proteínas de Helminto/genética , Sequência de Aminoácidos , Animais , Catepsina B/metabolismo , Catepsina C/metabolismo , Catepsina L/metabolismo , Bovinos , Cistatinas/química , Cistatinas/metabolismo , Escherichia coli/genética , Fasciola hepatica/enzimologia , Proteínas de Helminto/química , Proteínas de Helminto/metabolismo , Humanos , Organismos Geneticamente Modificados , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
17.
Parasitol Res ; 116(2): 503-509, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27817010

RESUMO

Although the life cycle of the equid stomach parasite Habronema muscae was disclosed more than 100 years ago, little is known about the effect of the developing nematode larvae in its intermediate host, Musca domestica. In a series of experiments, freshly hatched M. domestica larvae were exposed to H. muscae eggs contained in a faecal sample of a naturally infected horse. In daily intervals, 50 fly larvae were removed and transferred on a parasite-free larval rearing medium where they completed their development. Hatched flies were examined for the presence of Habronema third-stage larvae. In two subsequent control groups, flies spend their entire larval life in contaminated horse faeces and in a parasite-free larval rearing medium, respectively. Out of the 700 fly larvae used in the infection experiments, 304 developed into adult flies of which 281 were infected. The average nematode larval burden rose from 3.6 in the group with the shortest exposure to more than 25 in the groups with the longest exposure. The proportion of larvae that developed into the adult insect fell from 82 % in the uninfected control group to 27 % in the positive control group. The pupae of the positive control group were smaller and lighter than those of the uninfected control group. Lower pupal size and weight in the positive control group as well as a lower insect developing rate might be attributed to the destruction of adipose cells in the maggots by Habronema larvae.


Assuntos
Doenças dos Cavalos/parasitologia , Doenças dos Cavalos/transmissão , Muscidae/parasitologia , Infecções por Spirurida/veterinária , Spiruroidea/crescimento & desenvolvimento , Animais , Cavalos , Larva/crescimento & desenvolvimento , Larva/parasitologia , Muscidae/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Pupa/parasitologia , Infecções por Spirurida/parasitologia , Infecções por Spirurida/transmissão , Spiruroidea/fisiologia
18.
Exp Parasitol ; 139: 12-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24566044

RESUMO

Heterorhabditis is a nematode found in the soil that is used as an important biological control agent against various organisms. However, few studies have been performed of its use against snails and the present study is the first to investigate the effect of experimental exposure of Bradybaena similaris to Heterorhabditis indica LPP1. Two groups of 16 snails were formed: the control group (not exposed) and the treatment, which was exposed for three weeks to infective juveniles (J3) of H. indica LPP1. The entire experiment was conducted in duplicate, using a total of 64 snails. After this period, the snails were dissected to collect the hemolymph to evaluate the possible physiological alterations, namely total proteins, uric acid and hemolymph urea, as well as the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as a result of the infection. The terrariums were analyzed on alternate days throughout the experiment to count the dead snails. Intense proteolysis was observed in the infected snails. An increase in the level of uric acid and reduction of the hemolymph urea content indicated that the infection by H. indica results in the inversion of the excretion pattern of the host snail. Variations in the aminotransferase activities were also observed, with the infected group presenting significantly higher values (p<0.05) than the control group for both ALT and AST. The exposure to H. indica LPP1 caused 55% mortality, with the highest rate observed in the first week after exposure (30%). These results suggest that the use of H. indica LPP1 is a feasible alternative for the biological control of B. similaris.


Assuntos
Controle Biológico de Vetores/métodos , Rhabditoidea/fisiologia , Caramujos/parasitologia , Animais , Brasil , Hemolinfa/química , Histocitoquímica , Interações Hospedeiro-Parasita , Larva/parasitologia , Mariposas/parasitologia , Controle Biológico de Vetores/normas , Proteínas/análise , Caramujos/química , Caramujos/fisiologia , Transaminases/análise , Ureia/análise , Ácido Úrico/análise
19.
Exp Parasitol ; 145: 118-24, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25131776

RESUMO

Trypanosoma rangeli is a protozoan parasite of insects and mammals that is challenged by the constant action of reactive oxygen species, generated either by its own metabolism or through the host immune response. The aim of this work was to investigate whether T. rangeli is able to modify the redox state of its insect vector, Rhodnius prolixus, through the modulation of such antioxidant enzymes as superoxide dismutase (SOD), catalase, and GPx present in the midgut of the insect. We verified that in R. prolixus fed with blood infected with T. rangeli there is an increase in SOD activity in the anterior and posterior midguts. However, the activities of enzymes related to hydrogen peroxide and hydroperoxides metabolism, such as catalase and GPx, were decreased in relation to the insect control group, which was only fed blood. These changes in the redox state of the vector led to an increase in lipid peroxidation and thiol oxidation levels in the anterior and posterior midgut tissues. We also verified that the addition of 1 mM GSH in the blood meal of the infected insects increased the proliferation of these parasites by 50%. These results suggest that there is an increase in oxidative stress in the insect gut during T. rangeli infection, and this condition could contribute to the control of the proliferation of these parasites.


Assuntos
Insetos Vetores/parasitologia , Rhodnius/parasitologia , Trypanosoma rangeli/fisiologia , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Insetos Vetores/enzimologia , Peroxidação de Lipídeos , Oxirredução , Rhodnius/enzimologia , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo
20.
Front Cell Infect Microbiol ; 14: 1412345, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988814

RESUMO

P21 is a protein secreted by all forms of Trypanosoma cruzi (T. cruzi) with recognized biological activities determined in studies using the recombinant form of the protein. In our recent study, we found that the ablation of P21 gene decreased Y strain axenic epimastigotes multiplication and increased intracellular replication of amastigotes in HeLa cells infected with metacyclic trypomastigotes. In the present study, we investigated the effect of P21 in vitro using C2C12 cell lines infected with tissue culture-derived trypomastigotes (TCT) of wild-type and P21 knockout (TcP21-/-) Y strain, and in vivo using an experimental model of T. cruzi infection in BALB/c mice. Our in-vitro results showed a significant decrease in the host cell invasion rate by TcP21-/- parasites as measured by Giemsa staining and cell count in bright light microscope. Quantitative polymerase chain reaction (qPCR) analysis showed that TcP21-/- parasites multiplied intracellularly to a higher extent than the scrambled parasites at 72h post-infection. In addition, we observed a higher egress of TcP21-/- trypomastigotes from C2C12 cells at 144h and 168h post-infection. Mice infected with Y strain TcP21-/- trypomastigotes displayed higher systemic parasitemia, heart tissue parasite burden, and several histopathological alterations in heart tissues compared to control animals infected with scrambled parasites. Therewith, we propose that P21 is important in the host-pathogen interaction during invasion, cell multiplication, and egress, and may be part of the mechanism that controls parasitism and promotes chronic infection without patent systemic parasitemia.


Assuntos
Doença de Chagas , Proteínas de Protozoários , Trypanosoma cruzi , Animais , Humanos , Camundongos , Linhagem Celular , Doença de Chagas/parasitologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Interações Hospedeiro-Parasita , Camundongos Endogâmicos BALB C , Parasitemia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/genética , Trypanosoma cruzi/patogenicidade , Trypanosoma cruzi/fisiologia , Trypanosoma cruzi/metabolismo , Virulência
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