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1.
Appl Microbiol Biotechnol ; 108(1): 27, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38157006

RESUMO

Gastric and colorectal cancer are among the most frequently diagnosed malignancies of the gastrointestinal tract. Searching for methods of therapy that complements treatment or has a preventive effect is desirable. Bacterial metabolites safe for human health, which have postbiotic effect, are of interest recently. The study aimed to preliminary assessment of the safety, antimicrobial, and anti-cancer activity of cell-free metabolites of Gluconobacter oxydans strains isolated from Kombucha beverages as an example of the potential postbiotic activity of acetic acid bacteria (AAB). The study material consisted of five AAB strains of Kombucha origin and three human cell lines (gastric adenoma-AGS, colorectal adenoma-HT-29, and healthy cells derived from the endothelium of the human umbilical vein-HUVEC). Results of the study confirms the health safety and functional properties of selected AAB strains, including their potential postbiotic properties. The best potential anticancer activity of the AAB cell-free supernatants was demonstrated against AGS gastric adenoma cells. The conducted research proves the postbiotic potential of selected acetic acid bacteria, especially the KNS30 strain. KEY POINTS: •The beneficial and application properties of acetic acid bacteria are poorly studied. •Gluconobacter oxydans from Kombucha show a postbiotic activity. •The best anticancer activity of the G. oxydans showed against gastric adenoma.


Assuntos
Adenoma , Gluconobacter oxydans , Humanos , Gluconobacter oxydans/metabolismo , Ácido Acético/metabolismo
2.
Parasitol Res ; 122(7): 1621-1629, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37191686

RESUMO

American mink (Neovison vison) is an invasive species in the sylvatic environment of Poland. Mink are exposed to different parasite infections as their preys serve as intermediate and/or paratenic hosts. The study aimed to discriminate the pattern of intestinal parasite infections in mink inhabiting Biebrza (BNP) and Narew (NNP) national parks. Gastrointestinal tract examinations revealed Coccidia, Echinostomatidae, Taenidae, and Capillariidae parasites. There was no significant difference in the parasite burden of mink, but patterns of infections varied between both localizations. Coccidia were found in 3.8% of BNP vs. 6.7% of NNP mink. Fluke prevalence was significantly higher in NNP 27.5% compared to 7.7% in BNP mink. Tapeworms were only found in 3.4% of NNP mink. Significantly more Aonchotheca eggs were found in BNP 34.6% vs. 11.4% in NNP mink. The intensity of coccidiosis and aonchothecosis was low in both parks. Fluke intensity varied between low to moderate (ranging from 1 to 16) in BNP and low to massive (ranging from 1 to 117) in NNP mink. Coinfections of various parasite species were noted in both areas. Morphological and DNA analysis revealed that flukes belonged to Isthiomorpha melis and tapeworms to Versteria mustelae. It was the first isolation of V. mustelae in mink of those localizations. In conclusion, our study showed that mink indwelling Biebrza and Narew national parks are moderately infested with parasites. Results suggest that mink play an important role as a reservoir for parasites endangering endemic mustelids, becoming also a potential risk factor in case of accidental transmissions to farm mink. That is why, more strict biosecurity measures are required to protect farm mink.


Assuntos
Helmintos , Enteropatias Parasitárias , Parasitos , Animais , Vison/parasitologia , Parasitos/genética , Polônia/epidemiologia , Parques Recreativos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/veterinária
3.
Pathogens ; 12(5)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37242307

RESUMO

Vaccines are one of the greatest achievements of modern medicine, offering an effective way to fight and control infectious diseases [...].

4.
Comp Immunol Microbiol Infect Dis ; 86: 101818, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35576795

RESUMO

Dirofilaria repens is the causative agent of the zoonotic canine skin condition called subcutaneous dirofilariosis. Despite being endemic throughout much of Europe, little is known about host humoral responses to D. repens. To address this, we analyzed serum immunoglobulin isotypes recognizing D. repens somatic antigens (DrSA) in naturally infected dogs. Titers of anti-DrSA IgG and IgE, but not IgM were significantly higher in dogs infected with D. repens compared to those that were negative. Moreover, microfilaremic infections were associated with higher levels of IgG1 than IgG2, while occult infections occurred with significantly higher levels of IgG2 than IgG1. Finally, the measurement of anti-DrSA IgG antibodies allowed the detection of occult subcutaneous dirofilariosis in dogs.


Assuntos
Dirofilaria immitis , Dirofilaria repens , Dirofilariose , Doenças do Cão , Animais , Formação de Anticorpos , Dirofilariose/epidemiologia , Doenças do Cão/epidemiologia , Cães , Imunoglobulina G
5.
Sci Rep ; 12(1): 2288, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35145147

RESUMO

Dirofilaria repens is a parasitic nematode causing vector-borne disease (dirofilariasis), considered an emerging problem in veterinary and human medicine. Although main hosts are carnivores, particularly dogs, D. repens shows high zoonotic potential. The disease spreads uncontrollably, affecting new areas. Since there is no vaccine against dirofilariasis, the only way to limit disease transmission is an early diagnosis. Currently, diagnosis depends on the detection of microfilariae in the host bloodstream using modified Knott's test or multiplex PCR. However, the efficacy of tests relying on microfilariae detection is limited by microfilariae periodic occurrence. Therefore, a new reliable diagnostic test is required. Our study aimed to select new diagnostic markers for dirofilariasis with potential application in diagnostics. We focused on single epitopes to ensure high specificity of diagnosis and avoid cross-reactivity with the other parasite infections common in dogs. Using phage display technology and 12-mer peptides library, we selected epitopes highly reactive with IgG from sera of infected dogs. Additionally, our study presents the possibility of detecting D. repens specific cell-free DNA in dogs with no microfilaria but high IgG and IgM antibody levels against parasite somatic antigen.


Assuntos
Técnicas de Visualização da Superfície Celular/métodos , DNA de Helmintos/sangue , Dirofilaria repens/genética , Dirofilaria repens/isolamento & purificação , Dirofilariose/diagnóstico , Doenças do Cão/diagnóstico , Animais , Biomarcadores/sangue , Dirofilariose/parasitologia , Doenças do Cão/parasitologia , Cães , Imunoglobulina G/sangue
6.
Animals (Basel) ; 12(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35203133

RESUMO

The embryonic stage of filarial nematodes, or microfilariae (Mf), shows daily and seasonal periodicity that requires their migration through blood vessels into the lungs, where they are sequestered when not circulating in the peripheral blood. Therefore, Mf and the host endothelium are likely in a permanent state of hide and seek. Interestingly, filarial nematodes co-cultured in media with a murine endothelial cell line survive eight times longer than those cultured in media alone. This suggests that the endothelium is an important element of the immune response in filarial nematodes, perversely promoting their survival in the host. In this review, we will focus on potential pathways involved in the relationship between filarial nematodes and the host endothelium, including the role of endothelial ICAM/VCAM/PECAM adhesion molecules, surface markers involved in the passage of Mf through host tissue, anti-thrombolic effects caused by the presence of filarial nematodes (including plasmins), endothelial cell proliferation (VEGF), and other aspects of the immune activation of the endothelium. The aim of this review is to merge the knowledge about the cross-talk between Mf of different filarial nematode species and endothelial cells (EC), thus allowing a better understanding of the mechanism of these parasitic infections.

7.
Pathogens ; 11(2)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35215200

RESUMO

One of the adaptations of nematodes, which allows long-term survival in the host, is the production of proteins with immunomodulatory properties. The parasites secrete numerous homologs of human immune mediators, such as macrophage migration inhibitory factor (MIF), which is a substantial regulator of the inflammatory immune response. Homologs of mammalian MIF have been recognized in many species of nematode parasites, but their role has not been fully understood. The application of molecular biology and genetic engineering methods, including the production of recombinant proteins, has enabled better characterization of their structure and properties. This review provides insight into the current state of knowledge on MIF homologs produced by nematodes, as well as their structure, enzymatic activity, tissue expression pattern, impact on the host immune system, and potential use in the treatment of parasitic, inflammatory, and autoimmune diseases.

8.
Pathogens ; 10(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34451413

RESUMO

Toxocara canis is a zoonotic roundworm that infects humans and dogs all over the world. Upon infection, larvae migrate to various tissues leading to different clinical syndromes. The host-parasite interactions underlying the process of infection remain poorly understood. Here, we describe the application of a yeast two-hybrid assay to screen a human cDNA library and analyse the interactome of T. canis larval molecules. Our data identifies 16 human proteins that putatively interact with the parasite. These molecules were associated with major biological processes, such as protein processing, transport, cellular component organisation, immune response and cell signalling. Some of these identified interactions are associated with the development of a Th2 response, neutrophil activity and signalling in immune cells. Other interactions may be linked to neurodegenerative processes observed during neurotoxocariasis, and some are associated with lung pathology found in infected hosts. Our results should open new areas of research and provide further data to enable a better understanding of this complex and underestimated disease.

9.
Ann Agric Environ Med ; 28(2): 199-207, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34184498

RESUMO

INTRODUCTION AND OBJECTIVE: The aim was to review available data concerning the occurrence of protozoan parasites affecting carnivorous fur farm animals, such as: American mink, blue and silver foxes, and raccoon dogs. Although, many protozoan pathogens have been isolated in wild fur animals, some are still not recognised as relevant to particular fur farm animal species. Protozoans that have been isolated as causative agents of clinical cases and reported in these animals are: Cryptosporidium spp., Eimeria spp., Isospora spp., Leishmania infantum, Neospora caninum, Sarcocystis spp., and Toxoplasma gondii. Unfortunately, in most reports, neither clinical symptoms nor detailed pathogenicity and clinical pathology are satisfactory discriminated. This data is essential for preparing treatment and preventive measure protocols. Additionally, attempts to better understand the infections might be useful in the case of outbreaks. RESULTS: The results of the literature research revealed that some detected infections may have zoonotic potential, and are quite likely to be transmitted in both directions. The role of vectors, e.g. small rodents, birds, insects (sand-flies), or pets (cats and dogs), which might be involved in the transmission of various parasitic infections, is also discussed. The summarized list of protozoans involved can be used for further studies on the health and welfare aspects of fur farm animal breeding and public health issues.


Assuntos
Animais Domésticos/parasitologia , Carnívoros/parasitologia , Infecções Protozoárias em Animais/parasitologia , Animais , Humanos , Infecções por Protozoários/parasitologia , Infecções por Protozoários/transmissão , Infecções Protozoárias em Animais/transmissão , Zoonoses/parasitologia , Zoonoses/transmissão
10.
FEMS Microbiol Lett ; 368(5)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33629723

RESUMO

The study aimed to evaluate qualitatively and quantitatively the antimicrobial capacity of 10 potential probiotic Lactobacillus strains against model enteropathogens and spoilage microorganisms. The probiotic strains (live and heat-killed forms) were also assessed for their ability to inhibit adhesion of selected pathogens to Caco-2 cells. The largest inhibition zones (the diffusion method) were connected with the usage of whole bacteria cultures (WBC), also high and moderate with cell-free supernatant (CFS) and the lowest with cell-free neutralized supernatant (CNS). The highest antagonistic activity of Lactobacillus strains was observed against L. monocytogenes strains, moderate activity against Salmonella, Shigella, Escherichia coli, Pseudomonas and, the lowest against S.aureus, Bacillus and Enterococcus. The inhibition of adhesion to Caco-2 cells was very high in the case of E. coli, Salmonella and L. monocytogenes, and moderate in the case of S.aureus. On average, the inhibition effect was higher when pathogenic bacteria were treated by WBC, than heat-killed Lactobacillus. Although, in most samples, the effect was not significantly different (P> 0.05). The strains Lb. brevis O24 and Lb. rhamnosus K3 showed the biggest overall antimicrobial properties, and were most effective in adherence inhibition of investigated indicator strains. These bacteria or their metabolites can be used for the production of various foods or pharmaceutical products.


Assuntos
Antibacterianos/farmacologia , Antibiose/fisiologia , Bactérias/crescimento & desenvolvimento , Lactobacillus/fisiologia , Probióticos/farmacologia , Aderência Bacteriana/fisiologia , Bacteriocinas/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Escherichia coli/crescimento & desenvolvimento , Microbiologia de Alimentos/métodos , Humanos , Listeria monocytogenes/crescimento & desenvolvimento , Pseudomonas/crescimento & desenvolvimento , Salmonella/genética , Shigella/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento
11.
Ann Parasitol ; 67(4): 619-626, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35247302

RESUMO

Tapeworm infections in Konik Polski horses from Biebrza National Park were investigated in this study. Faecal samples were collected 10 times: in 2012 - 1 time, in 2013 - 4 times, in 2014 - 4 times and in 2015 - 1 time. In total, 162 faecal samples were collected and tested. Faecal egg counts (FECs) method was used in the study. Positive samples with cestode eggs were noted only twice - in October 2012 and December 2013 in two adult mares (9 and 11 years old). The determined prevalence was surprisingly low comparing to other studies, 4.3% in October 2013 and 28.5% in December 2013. Parasite genomic DNA was isolated from posterior proglottids of tapeworms found in horse faeces after deworming, PCR technique was applied in order to determine the species of these tapeworms. No specific products were obtained using primers specific to rDNA sequence, whereas, a 620 bp fragment encoding mitochondrial cytochrome oxidase I (COI) was amplified and sequenced. Nucleotide sequence analysis revealed a 100% homology to a corresponding fragment form Anoplocephala perfoliata tapeworm originating from a horse from the Czech Republic. To our knowledge this is the first report applying molecular techniques to tapeworm identification in Konik Polski horses.


Assuntos
Cestoides , Infecções por Cestoides , Doenças dos Cavalos , Animais , Cestoides/genética , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Infecções por Cestoides/veterinária , Fezes/parasitologia , Feminino , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/parasitologia , Cavalos , Parques Recreativos
12.
Ticks Tick Borne Dis ; 12(1): 101586, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33059172

RESUMO

The distribution and prevalence of zoonotic pathogens infecting ixodid ticks in Western Europe have been extensively examined. However, data on ticks and tick-borne pathogens in Eastern Europe, particularly Ukraine are scarce. The objective of the current study was, therefore, to investigate the prevalence of Anaplasma phagocytophilum, Anaplasmataceae, Rickettsia spp., Babesia spp., Bartonella spp., and Borrelia burgdorferi sensu lato in engorged and questing ixodid ticks collected from five administrative regions (oblasts) of Ukraine, namely Chernivtsi, Khmelnytskyi, Kyiv, Ternopil, and Vinnytsia. The ticks were collected from both wild and domestic animals and from vegetation. Of 524 ixodid ticks collected, 3, 99, and 422 ticks were identified as Ixodes hexagonus, Ixodes ricinus, and Dermacentor reticulatus, respectively. DNA samples individually extracted from 168 questing and 354 engorged adult ticks were subjected to pathogen-specific PCR analyses. The mean prevalence in I. ricinus and D. reticulatus were, respectively: 10 % (10/97) and 3 % (12/422) for A. phagocytophilum; 69 % (67/97) and 52 % (220/422) for members of the Anaplasmataceae family; 25 % (24/97) and 28 % (117/422) for Rickettsia spp.; 3 % (3/97) and 1 % (6/422) for Babesia spp.; and 9 % (9/97) and 5 % (20/422) for Bartonella spp. Overall, between the five cities, there was no significant difference in the prevalence of any of the pathogens for the respective ticks (p > 0.05). The prevalence of B. burgdorferi s. l. in the questing and engorged I. ricinus varied from 0 to 27 % and 14-44%, respectively, with no statistical significance identified between the five cities (p > 0.05). In addition to reporting the updated data for Kyiv and Ternopil, this study is the first to provide the prevalences of the tick-borne pathogens for Chernivtsi, Khmelnytskyi, and Vinnytsia. This investigation is also the first to detect Neoehrlichia mikurensis in ixodid ticks from Ukraine. These new data will be useful for medical and veterinary practitioners as well as public health officials when diagnosing infections and when implementing measures to combat tick-borne diseases in Ukraine.


Assuntos
Infecções por Anaplasmataceae/veterinária , Babesiose/epidemiologia , Infecções por Bartonella/veterinária , Doença de Lyme/veterinária , Infecções por Rickettsia/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Anaplasmataceae/isolamento & purificação , Infecções por Anaplasmataceae/epidemiologia , Infecções por Anaplasmataceae/microbiologia , Animais , Animais Domésticos , Animais Selvagens , Babesia/isolamento & purificação , Babesiose/parasitologia , Bartonella/isolamento & purificação , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , Grupo Borrelia Burgdorferi/isolamento & purificação , Dermacentor/microbiologia , Dermacentor/parasitologia , Ixodes/microbiologia , Ixodes/parasitologia , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Plantas , Prevalência , Rickettsia/isolamento & purificação , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Ucrânia/epidemiologia
13.
Front Vet Sci ; 7: 590, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33134335

RESUMO

Subcutaneous dirofilariosis is a zoonotic disease emerging throughout Europe caused by the filarial nematode Dirofilaria repens. Despite its increasing prevalence, there is a large gap in knowledge of the impact of the parasite on the host. Currently classified as being non-pathogenic, recent evidence suggests that skin dirofilariosis is associated with dermatological conditions including concomitant pruritus, neoplastic processes, inflammation, and even blindness in dogs and humans. The aim of this study was to determine if natural canine D. repens infection leads to biological changes in the canine host. In a real-life veterinary clinic setting, animals are often presented to clinicians for unrelated issues, and D. repens is incidentally identified during inspection. As such, we compared hematological and biochemical parameters of 218 uninfected and 197 dogs naturally infected with D. repens. Interestingly, animals infected with D. repens had lower numbers of lymphocytes (p < 0.001), red blood cells (p < 0.001), and thrombocytes (p = 0.025), decreased hematocrit (p < 0.001), and increased alkaline phosphatase (p = 0.016) and creatinine activity (p = 0.023) compared to uninfected dogs. We further selected a subpopulation of 214 dogs having prima facie hematological and biochemical results within normal reference ranges to evaluate the effect of D. repens infections in seemingly healthy dogs. Among these patients, 93 dogs infected with D. repens had lower numbers of lymphocytes (p = 0.031), red blood cells (p = 0.025), and hematocrit (p = 0.002), higher glucose levels (p = 0.023), and border line elevated alkaline phosphatase levels (p = 0.054) compared to 121 uninfected animals. Despite being categorized as asymptomatic, we have observed hematological and biochemical changes associated with D. repens infections in dogs, and our data suggest that dirofilariosis may induce a state of chronic stress. These results link the presence of skin dirofilariosis to biological changes in the canine host, suggesting a mechanism for pathogenicity and shedding new light on the host-parasite relationship.

14.
Front Vet Sci ; 7: 577466, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195580

RESUMO

Subcutaneous dirofilariosis in dogs, caused by Dirofilaria repens, is an underdiagnosed disease, now recognized for its zoonotic potential, and growing distribution and prevalence across Europe and Asia. Our understanding of the pathogenicity in human and canine host remains unclear, but case reports suggest that microfilariae (Mf) as well as adult D. repens may directly cause internal organs damage or may be a factor complicating the course of other ailments. The purpose of the study was to report high Mf in dogs and to discuss potential relevance with co-morbidity. Our data from a modified Knott's test performed on 62 infected dogs indicate that the median Mf count in D. repens infections is 675 Mf/ml and we consider microfilaremia above 10,000 Mf/ml as high intensity. This collection of case reports discusses 4 cases of high intensity D. repens microfilaremia in companion dogs; one presenting pathology from a very high intensity of adult D. repens with post-treatment complications, and 3 dogs in which high microfilaremia was detected incidentally during the management of other primary illnesses. To our knowledge this report describes the highest D. repens microfilaremia ever detected in a dog, at 178,000 Mf/ml. The issue of high microfilaremic infections in dogs is poorly studied and there is growing need to identify the presentation and understand the mechanisms of associated pathogenesis in the host-parasite relationship.

15.
Probiotics Antimicrob Proteins ; 12(3): 1025-1038, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31463690

RESUMO

Twenty-nine Lactobacillus plantarum strains isolated from different types of Polish regional cheeses (Oscypek and Korycinski) were assessed for selected probiotic properties and anti-staphylococcal activity. Most of the tested L. plantarum strains were considered safe. Whole bacterial cultures (WBC) and cell-free supernatants (CFSs) of L. plantarum strains inhibited growth of Staphylococcus aureus (average inhibition growth zones were 2.8 mm ± 1.2 and 2.8 mm ± 1.1 respectively). Moreover, almost all neutralized, catalase-treated cell-free supernatants (CFN) of L. plantarum cultures also exhibited slight anti-staphylococcal activity in vitro. The most promising strains Os4 and Kor14 were selected for further study. Both strains were able to survive during digestive gastro-intestinal passage model. Live cells of L. plantarum Os4 and Kor14 caused the strongest inhibition of S. aureus adhesion to Caco-2 cells comparing with CFN and heat-killed bacterial cells. S. aureus and L. plantarum (Os4 or Kor14) co-cultured in skim milk resulted in growth inhibition of S. aureus in both 8 °C and 37 °C incubation temperatures. Observed abilities, demonstrated for L. plantarum Os4 and Kor14, confirms that these strains could be used in the food industry as protective cultures.


Assuntos
Antibiose , Queijo/microbiologia , Lactobacillus plantarum , Probióticos , Staphylococcus aureus , Células CACO-2 , Microbiologia de Alimentos , Humanos , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo
16.
Sci Rep ; 9(1): 16165, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700060

RESUMO

Protein-based drug discovery strategies have the distinct advantage of providing insights into the molecular mechanisms of chemical effectors. Currently, there are no known trehalose-6-phosphate phosphatase (TPP) inhibitors that possess reasonable inhibition constants and chemical scaffolds amenable to convenient modification. In the present study, we subjected recombinant TPPs to a two-tiered screening approach to evaluate several diverse compound groups with respect to their potential as TPP inhibitors. From a total of 5452 compounds tested, N-(phenylthio)phthalimide was identified as an inhibitor of nematode TPPs with apparent Ki values of 1.0 µM and 0.56 µM against the enzymes from the zoonotic roundworms Ancylostoma ceylanicum and Toxocara canis, respectively. Using site-directed mutagenesis, we demonstrate that this compound acts as a suicide inhibitor that conjugates a strictly conserved cysteine residue in the vicinity of the active site of nematode TPPs. The anthelmintic properties of N-(phenylthio)phthalimide were assessed in whole nematode assays using larvae of the ascaroids T. canis and T. cati, as well as the barber's pole worm Haemonchus contortus. The compound was particularly effective against each of the ascaroids with an IC50 value of 9.3 µM in the survival assay of T. cati larvae, whereas no bioactivity was observed against H. contortus.


Assuntos
Anti-Helmínticos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Helminto/antagonistas & inibidores , Nematoides/enzimologia , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Ftalimidas/farmacologia , Animais , Proteínas de Helminto/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo
17.
Parasitol Res ; 118(10): 2925-2933, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31396715

RESUMO

The effect of Toxocara canis antigens on cytokine production by human THP-1 macrophages was studied in vitro. Toxocara Excretory-Secretory products (TES) and recombinant mucins (Tc-MUC-2, Tc-MUC-3, Tc-MUC-4, and Tc-MUC-5) as well as deglycosylated forms of these antigens were used in the study. TES products stimulated macrophages to produce the innate proinflammatory IL-1ß, IL-6, and TNF-α cytokines regardless of the presence of glycans. Recombinant mucins induced glycan-dependent cytokine production. Sugar moieties led to at least 3-fold higher production of regulatory IL-10 as well as proinflammatory cytokines. The presence of glycans on mucins also affected the downstream signalling pathways in stimulated cells. The most prominent difference was noted in AKT and AMPK kinase activation. AKT phosphorylation was observed in cells stimulated with glycosylated mucins, whereas treatment with deglycosylated antigens led to AMPK phosphorylation. MAP kinase family members such as JNK and p38 and c-Jun transcription factor were phosphorylated in both cases what suggests that toll-like receptor signalling may be involved in mucin-treated macrophages. This pathway is however modified by other signalling molecules as only mucins containing intact sugars significantly induced the production of cytokines.


Assuntos
Citocinas/metabolismo , Macrófagos/imunologia , Mucinas/imunologia , Polissacarídeos/imunologia , Toxocara canis/imunologia , Quinases Proteína-Quinases Ativadas por AMP , Animais , Linhagem Celular , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/imunologia , Células THP-1 , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
J Vet Res ; 63(2): 197-203, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31276059

RESUMO

INTRODUCTION: Farm mink (Neovison vison) can be naturally exposed to T. canis and T. leonina pathogens on the farm. If mink were hosts, it would imply some veterinary public health as well as animal welfare issues. For this reason, the aim of the study was to determine whether mink might be definitive or paratenic hosts of these parasites. MATERIAL AND METHODS: Four groups of mink were infected with both parasite species using larvated eggs or feed containing mouse tissue previously infected with the parasites. Following inoculation, the infections were monitored in vivo by faecal examination for 14 weeks p.i., and then western blotting and ELISA were performed. RESULTS: Coprology did not reveal any canine roundworm eggs, neither were nematodes found in mink intestines during post mortem examination. The specific IgG antibodies recognising excretory/secretory (ES) antigens of both parasite species were identified in mink sera. Single T. leonina tissue larvae were found in digested organs. CONCLUSIONS: Our results confirm that farm mink may contribute both T. canis and T. leonina infections. It was proved that farm mink were not their definitive hosts, and therefore mink faeces need not be considered a source of canine roundworm eggs in any soil it fertilises. Nonetheless, as farm mink may be a paratenic host for both parasite species, this may have some impact on the health and welfare of infected animals.

19.
J Vet Res ; 63(2): 205-214, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31276060

RESUMO

INTRODUCTION: Canine roundworm T. canis and T. leonina infections were investigated in experimentally infected farm mink (Neovison vison) to describe the pattern of pathological lesions in this paratenic host. MATERIAL AND METHODS: Material and MethodsInfections in mink developed following ingestion of embryonated eggs of either parasite or mice tissue infected with both parasite species. RESULTS: Comparative analysis of haematoxylin- and eosin-stained slides showed essential differences among the experimental groups. The lesions observed included eosinophil and mononuclear inflammatory infiltrates of the intestinal wall and local lymph nodes, inflammation and haemorrhages in liver tissues, and interstitial inflammation and mineralisation of the kidneys and lungs. Larvae migrating through the minks' bodies also caused particularly salient enlargement of lymphoid follicles in the spleen and inflammatory infiltrates of mononuclear cells in skeletal and heart muscles. CONCLUSIONS: It is assumed that histopathological lesions appeared as a local and general host response to invasive L3 T. canis and T. leonina larvae migrating through the tissues of infected farm mink. Interestingly, mink infected with embryonated eggs had more pronounced lesions than animals infected with tissue larvae. Detailed histopathological examinations of parenchymal organs and striated muscles revealed lesions resembling those observed in other paratenic host species due to toxocarosis.

20.
Probiotics Antimicrob Proteins ; 11(3): 820-829, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30141062

RESUMO

In the current study, the probiotic activity of ten Lactobacillus (Lb.) strains, previously isolated from the traditional Polish fermented vegetable, was characterized. Strains were assessed for adhesion to human intestinal epithelial Caco-2 cells and regulation of selected cytokine production (IL-1ß, IL-6, IL-10, IL-23, and TNF-α) by THP-1 macrophages. The effect of tested strains on Caco-2 cell apoptosis was also investigated using a caspase-3 assay. Adhesion capacity was strain-dependent (1.29-8.24% of initial population). Highest adhesion was observed for Lb. brevis O24. All Lactobacillus strains investigated in this study stimulated two- to threefold increase in TNF-α, IL-1ß, and IL-6 production, compared to the control. Additionally, selected strains of Lactobacillus caused a significant decrease of pro-inflammatory cytokine production by lipopolysaccharide (LPS)-stimulated THP-1 cells. Almost all Lactobacillus investigated in this study are potent stimulators of IL-10 production. All tested Lactobacillus cells slightly increased the caspase-3 activity in Caco-2 cells. Lb. casei O18 was the most inducing strain. The tested strains had no effect on staurosporine (STS)-induced caspase-3 activity. According to these results, the most promising strains are Lb. plantarum O20, two strains Lb. brevis O22 and O24, and Lb. rhamnosus K3. These newly identified lactobacilli hold promise for use as probiotics in functional food applications.


Assuntos
Trato Gastrointestinal/microbiologia , Lactobacillus/fisiologia , Aderência Bacteriana , Células CACO-2 , Citocinas/genética , Citocinas/metabolismo , Alimentos Fermentados/microbiologia , Trato Gastrointestinal/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lactobacillus/genética , Macrófagos/metabolismo , Modelos Biológicos , Verduras/microbiologia
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