Fasciola hepatica é o parasito causador da fasciolose, doença transmitida através dos alimentos, que afeta a produção pecuária e a saúde humana. Embora a doença seja tratada com anti-helmínticos, as possibilidades de reinfecção e o desenvolvimento de resistência ao triclabendazol exigem novas estratégias de controle. Os produtos de excreção/secreção liberados pelo parasito durante a infecção auxiliam a sobrevivência do parasito, protegendo-o das respostas do hospedeiro, permitindo sua sobrevivência durante um longo período no hospedeiro vertebrado e a finalização do ciclo larval no hospedeiro intermediário. Este trabalho teve como objetivo gerar uma análise proteômica dos estágios intra-mamífero, adulto e NEJ (juvenil recentemente desencistado), de F. hepatica. Até o momento, os dados gerados representam o maior número de proteínas identificadas para este parasito. A classificação funcional revelou a presença de proteínas envolvidas em diferentes processos biológicos, muitos dos quais representam achados originais para este organismo. Além disso, os padrões de infecção dos parasitos são frequentemente ligados ao comportamento do hospedeiro intermediário, o qual pode desempenhar um papel na distribuição e acumulação dos parasitos. Os dois proteomas analisados neste trabalho possuem diferenças em abundância de proteínas individuais e entre as categorias funcionais. Estas diferenças podem ser causadas pelas características do ciclo biológico do parasito em cada hospedeiro (duração do ciclo de vida, quantidade de cercárias geradas, durabilidade das metacercárias, competição com outros parasitos), aspectos biológicos (como idade ou espécie) ou variações ambientais (temperatura, umidade, estação). A compreensão dos mecanismos moleculares subjacentes à interação com os hospedeiros intermediário e definitivo pode fornecer dados que auxiliem a busca de novos alvos no diagnóstico e controle da fasciolose. / Fasciola hepatica is the agent of fasciolosis, a foodborne zoonosis that affects livestock production and human health. Although flukicidal drugs are available, re-infection and expanding resistance to triclabendazole demand new control strategies. Parasite compounds released during infection, known as excretory/secretory products, mediate parasite survival within the host. ESP are thought to protect parasites from host responses, allowing them to survive for a long period in the vertebrate host and complete their larval cycle in the intermediate host. This work provides in-depth proteomic analysis of F. hepatica intra-mammalian stages, adult and NEJ (newly existed juvenile), and represents the largest number of proteins identified to date for this parasite. Functional classification revealed the presence of proteins involved in different biological processes, many of which represent original findings for this organism and are can be vital for parasite survival within the host. In addition, infection patterns of parasites are often tied to host behavior, and intermediate host behavior can play a role in shaping the distribution and accumulation of parasites. The two proteomes analyzed here have differences in protein abundance, categories and individual proteins. The differences found here could be due to differences in the biological cycle of the parasite in the host (as duration of the life cycle, amount of cercariae generated, durability of metacercariae, competition with other parasites), biological aspects (as age or species) or environmental variabilities (as temperature, humidity, season). Understanding the molecular mechanisms underlying the complex interaction with the intermediate and definitive host could provide relevant clues, aiding the search for novel targets in diagnosis and control of fasciolosis.

Made available in DSpace on 2018-08-01T22:56:50Z (GMT). No. of bitstreams: 1 tese_7265_Laila Machado.pdf: 3008300 bytes, checksum: d3b207ad3439153c5340a5e72562426e (MD5) Previous issue date: 2015-07-28 / A fasciolose bovina apresenta alta prevalência na região sul do Espírito Santo e uma das principais características deste processo é a fibrose hepática. Em matadouros frigoríficos é comum a condenação de fígados que apresentam fibrose por fasciolose, mesmo na ausência do parasito. Objetivou-se com este estudo realizar o diagnóstico diferencial de lesões fibróticas em fígados bovinos condenados por esta enfermidade. Foram avaliados macro e microscopicamente fígados bovinos condenados por fasciolose no Sul do Estado do Espírito Santo e consideradas as variáveis: infiltrado inflamatório, fibrose, metaplasia mucoide e macrófagos espumosos nas regiões periportais. Utilizou-se estatística descritiva e teste de Qui-quadrado seguido do teste V de Cramer a 5% de probabilidade. No total, 28 fígados foram analisados e revelaram fibrose periportal e infiltrado inflamatório linfocítico predominantemente discretos. Também se verificou inflamação eosinofílica, predominantemente intensa. Os macrófagos espumosos foram observados em 25% dos casos e a metaplasia mucoide em 39,28%. Houve associação significativa entre fibrose e infiltrado inflamatório linfocítico e vice-versa, entre fibrose e macrófagos espumosos e vice-versa e entre metaplasia e infiltrado inflamatório eosinofílico. Conclui-se com este estudo que a fibrose e o infiltrado inflamatório são as alterações mais frequentes em fígados condenados por fasciolose. Contudo, a fibrose hepática também está associada à presença de macrófagos espumosos, que pode ser decorrente de outras enfermidades. Assim, a fibrose, isoladamente, não deveria ser utilizada como um critério para condenação por fasciolose. Por outro lado, a metaplasia mucoide é uma alteração frequente em animais com esta doença e poderia ser considerada como um critério de julgamento pela histopatologia.

Fasciola hepatica é o parasito causador da fasciolose, doença transmitida através dos alimentos, que afeta a produção pecuária e a saúde humana. Embora a doença seja tratada com anti-helmínticos, as possibilidades de reinfecção e o desenvolvimento de resistência ao triclabendazol exigem novas estratégias de controle. Os produtos de excreção/secreção liberados pelo parasito durante a infecção auxiliam a sobrevivência do parasito, protegendo-o das respostas do hospedeiro, permitindo sua sobrevivência durante um longo período no hospedeiro vertebrado e a finalização do ciclo larval no hospedeiro intermediário. Este trabalho teve como objetivo gerar uma análise proteômica dos estágios intra-mamífero, adulto e NEJ (juvenil recentemente desencistado), de F. hepatica. Até o momento, os dados gerados representam o maior número de proteínas identificadas para este parasito. A classificação funcional revelou a presença de proteínas envolvidas em diferentes processos biológicos, muitos dos quais representam achados originais para este organismo. Além disso, os padrões de infecção dos parasitos são frequentemente ligados ao comportamento do hospedeiro intermediário, o qual pode desempenhar um papel na distribuição e acumulação dos parasitos. Os dois proteomas analisados neste trabalho possuem diferenças em abundância de proteínas individuais e entre as categorias funcionais. Estas diferenças podem ser causadas pelas características do ciclo biológico do parasito em cada hospedeiro (duração do ciclo de vida, quantidade de cercárias geradas, durabilidade das metacercárias, competição com outros parasitos), aspectos biológicos (como idade ou espécie) ou variações ambientais (temperatura, umidade, estação). A compreensão dos mecanismos moleculares subjacentes à interação com os hospedeiros intermediário e definitivo pode fornecer dados que auxiliem a busca de novos alvos no diagnóstico e controle da fasciolose. / Fasciola hepatica is the agent of fasciolosis, a foodborne zoonosis that affects livestock production and human health. Although flukicidal drugs are available, re-infection and expanding resistance to triclabendazole demand new control strategies. Parasite compounds released during infection, known as excretory/secretory products, mediate parasite survival within the host. ESP are thought to protect parasites from host responses, allowing them to survive for a long period in the vertebrate host and complete their larval cycle in the intermediate host. This work provides in-depth proteomic analysis of F. hepatica intra-mammalian stages, adult and NEJ (newly existed juvenile), and represents the largest number of proteins identified to date for this parasite. Functional classification revealed the presence of proteins involved in different biological processes, many of which represent original findings for this organism and are can be vital for parasite survival within the host. In addition, infection patterns of parasites are often tied to host behavior, and intermediate host behavior can play a role in shaping the distribution and accumulation of parasites. The two proteomes analyzed here have differences in protein abundance, categories and individual proteins. The differences found here could be due to differences in the biological cycle of the parasite in the host (as duration of the life cycle, amount of cercariae generated, durability of metacercariae, competition with other parasites), biological aspects (as age or species) or environmental variabilities (as temperature, humidity, season). Understanding the molecular mechanisms underlying the complex interaction with the intermediate and definitive host could provide relevant clues, aiding the search for novel targets in diagnosis and control of fasciolosis.

L’émergence et la ré-émergence de maladies que nous connaissons depuis ces cents dernières années représentent une véritable crise sanitaire en grande partie due aux perturbations anthropiques qui modifient les écosystèmes et les interactions entre les parasites et leurs hôtes. La prévention et le contrôle des maladies infectieuses nécessitent la compréhension de leur dynamique dans l’ensemble des compartiments dans lesquels elles circulent. Parmi ces maladies, la fasciolose est une maladie particulièrement sensible aux changements liés à l’Homme. Cette zoonose causée par le parasite Fasciola hepatica, est communément reconnue comme un problème vétérinaire, mais aussi de santé publique, dans certaines régions du monde. Notre étude vise à comprendre la dynamique de circulation et les risques d'émergence de la fasciolose dans un contexte de forte anthropisation. Il s'agit (1) d'étudier la dynamique de l’hôte intermédiaire, un mollusque de la famille des lymnaieidae. (2) de comprendre la dynamique et la diversité du parasite entre et au sein de ses différents compartiments hôtes définitifs. Ces travaux ont été menés sur le territoire camarguais sur le domaine de la Tour du Valat, nous permettant d’avoir accès aux hôtes définitifs, sauvages (ragondins et sangliers), domestiques (taureaux traités et non traités) et à l’hôte intermédiaire, Galba truncatula appelé communément limnée tronquée. Dans un premier temps, nous avons caractérisé la végétation des habitats favorables à la présence du mollusque et nous avons trouvé que les mares semblaient être des zones présentant un risque plus important que les canaux d’irrigation pour la transmission de la fasciolose. Puis, nous nous sommes intéressée à l’influence des habitats sur la dynamique de G. truncatula par des approches de génétique des populations. Nos résultats ont permis de montrer que la permanence des habitats et la connectivité influencent le mode de reproduction, la structuration des populations et la dispersion des limnées en Camargue. Dans un second temps, nous avons étudié la dynamique et la circulation du parasite au sein du compartiment hôte définitif. Nos résultats de la génétique des populations du parasite chez les hôtes définitifs, nous ont indiqué qu’il existait sur notre site d’étude plusieurs sites de transmission constituant un seul grand foyer global. Par ailleurs, l’étude de la circulation du parasite entre les hôtes définitifs suggère le rôle des sangliers dans la dispersion de la maladie et le rôle des ragondins dans le maintien du cycle de la fasciolose. Cette étude met en évidence l’intérêt de mener des études à long terme et l’importance de prendre en compte tous les compartiments impliqués pour comprendre l’épidémiologie d’une maladie. Elle souligne également le rôle des activités humaines et de l’écosystème dans la dynamique de la fasciolose. Le but final de cette étude est de proposer une gestion intégrée adaptée au contexte camarguais afin de limiter l’impact sanitaire de la fasciolose mais aussi des autres maladies liées à l’élevage dans cette région. / The emergence and re-emergence of diseases encountered over the last hundred years represent a real health crisis largely due to anthropic disturbances that affect the ecosystems as well as the interactions between parasites and hosts. The prevention and control of emerging infectious diseases require an in-depth understanding of their dynamics in all the compartments in which they occur. Among these diseases, Fasciolosis is particularly sensitive to human related changes. This zoonosis caused by the parasite Fasciola hepatica, is commonly recognized as a veterinary problem and major public health issue in certain countries. Our study aims to understand the circulation dynamics and risks of fasciolosis emergence in a context of high anthropization. Our objective is (1) to study the dynamics of the intermediate host, a mollusc of the lymnaieidae family. (2) to understand the dynamics and diversity of the parasite between and within its different definitive host compartments. This work was carried out in the Camargue in the Tour du Valat estate, allowing us to have access to the definitive hosts, wild (nutria and wild boars), domestic (treated and untreated bulls) and the intermediate host, Galba truncatula. First, we characterized the habitats that are favorable to the intermediate host G. truncatula, presence in Camargue and we found that ponds appear to be areas of higher risk than irrigation channels for fasciolosis transmission. Then, we became interested in the influence of habitats on the dynamics of G. truncatula through population genetics approaches, our results showed that habitat permanence and connectivity influence the reproduction mode, population structure and dispersal of G. truncatula in the Camargue. In a second step, we studied the dynamics and circulation of the parasite within the definitive host compartment. Our results of the population genetic analyses of definitive hosts indicated that there were several transmission sites on our study area that constituted a single large global outbreak. In addition, the study of the circulation of the parasite between wildlife and domestic animals suggests the role of wild boars in the spread of the disease and the role of nutrias in maintaining the fasciolosis cycle. Our work highlights the value of long term studies and the importance of taking into account all the compartments involved to understand the epidemiology of a disease. They also emphasize the role of human activities and ecosystem in the dynamics of fasciolosis. The ultimate goal of this study is to propose integrated management measures adapted to the Camargue context in order to limit the health impact of fasciolosis and other livestock diseases in the region.

Este trabalho foi realizado com o objetivo de melhor identificar e estudar comparativamente as lesões histológicas do fígado decorrente da fasciolose hepática em três espécies de animais domésticos. Foram examinados fígados infectados por Fasciola hepatica de bovinos e bubalinos provenientes de matadouros e frigoríficos oficialmente inspecionados no Estado do Paraná e fígados de ovinos de propriedades particulares, onde o abate era realizado no local. O material foi processado pela técnica de rotina para histopatologia. As colorações utilizadas foram Hematoxilina-Eosina, Tricrômico de Schorr, Tricrômico de Mallory e Azul de Toluidina. As principais lesões observadas foram cortes de parasitas em ductos biliares, fibrose portal, hiperplasia de ducto biliar, fibrose de parede de ducto biliar e infiltração por linfócitos, plasmócitos, eosinófilos e neutrófilos. Considerando os resultados obtidos, conclui-se que a fasciolose em bovinos e bubalinos se trata de uma fasciolose crônica, principalmente devido a idade de abate ser maior nessas espécies. Nos ovinos o predomínio de eosinófilos caracteriza fase inicial de fasciolose crônica, sendo a idade de abate dos mesmos inferior as outras espécies

Made available in DSpace on 2015-03-26T13:46:32Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1301950 bytes, checksum: 6fbbf4b2a61f2a6e15625bb5f54e5cd6 (MD5) Previous issue date: 2008-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The in vitro effects of four isolates of the nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium sinense (SF53) and Pochonia chlamydosporia (VC1 and VC4) on eggs of Fasciola hepatica and Schistosoma mansoni was evaluated in two assays (A and B). Eggs of F. hepatica (assay A) and S. mansoni (assay B) were incubated in Petri dishes with 2% water-agar inoculated with the grown fungal isolates and a control without fungus. After seven, 14 and 21 days post- inoculation, one hundred eggs were removed and classified according to the following parameters: type 1, lytic effect without morphological damage to eggshell; type 2, lytic effect with morphological alteration of embryo and eggshell; and type 3, lytic effect with morphological alteration of embryo and eggshell, with hyphal penetration and internal egg colonization. In assay A, D. flagrans (AC001) and M. sinense (SF53) showed results only for type-1 effect on F. hepatica eggs, but with no significant difference (p>0.01) between them. P. chlamydosporia (VC1 and VC4) showed percentage results for ovicidal activity of type-1, -2 and -3 effects on F. hepatica eggs, with type-3 effect of 12.8% (VC1) and 16.5% (VC4); 14.4% (VC1) and 18.7% (VC4), 20.1% (VC1) and 21.5% (VC4) at seven, 14 and 21 days respectively. At the end of assay A no difference was found in the action of VC1 and VC4 for type-1, -2 and -3 effects over the three studied periods. In assay B, D. flagrans (AC001) and M. sinense (SF53) showed percentage results only for type 1 effect on S. mansoni eggs, with no significant difference (p>0.01) between them. P. chlamydosporia showed ovicidal activity on S. mansoni eggs with percentage results for type-1, -2 and -3 effects showing type 3 effect of: 26.6% (VC1) and 17.2% (VC4); 25.6% (VC1) and 22.6% (VC4); 26.3% (VC1) and 23.0% (VC4) at seven, 14 and 21 days respectively. At the end of the assay B, no difference was found in the action between the isolates VC1 and VC4 for type-1, -2 and -3 effects as well. The results of the A and B in vitro assays showed that P. chlamydosporia (VC1 and VC4) negatively affected F. hepatica and S. mansoni eggs and can therefore be used as biological control agent for these helminths. / Avaliou-se, em dois ensaios experimentais (A e B), a ação in vitro de quatro isolados de fungos nematófagos dos gêneros Duddingtonia flagrans (AC001), Monacrosporium sinense (SF53) e Pochonia chlamydosporia (VC1 e VC4) sobre ovos de Fasciola hepatica e Schistosoma mansoni. Ovos de F. hepatica (ensaio A) e ovos de S. mansoni (ensaio B) foram vertidos em placas de Petri com ágar-água 2% com os isolados fúngicos crescidos, e em placas de Petri sem fungo como controle. Ao completarem sete, 14 e 21 dias, aproximadamente cem ovos foram removidos e classificados de acordo com os seguintes parâmetros: efeito do tipo 1, efeito lítico sem prejuízo morfológico à casca do ovo; efeito do tipo 2, efeito lítico com alteração morfológica da casca e embrião; e efeito do tipo 3, efeito lítico com alteração morfológica do embrião e da casca, além de penetração de hifas e colonização interna do ovo. No ensaio A, os fungos D. flagrans (AC001) e M. sinense (SF53) apresentaram resultados percentuais somente para o efeito do tipo 1 sobre os ovos de F. hepatica, porém sem apresentar diferença significativa (p>0,01) entre eles. O fungo P. chlamydosporia (VC1 e VC4) demonstrou resultados percentuais de atividade ovicida para os efeitos dos tipos 1, 2 e 3 sobre os ovos de F. hepatica, com efeito do tipo 3 de 12,8% (VC1) e 16,5% (VC4); 14,4% (VC1) e 18,7% (VC4), 20,2% (VC1) e 21,5% (VC4), respectivamente aos sete, 14 e 21 dias. Ao final do ensaio experimental A, não foi observada diferença na ação de VC1 e VC4 para os efeitos dos tipos 1, 2 e 3 ao longo dos três períodos estudados. No ensaio experimental B, os fungos D. flagrans (AC001) e M. sinense (SF53) apresentaram somente resultados percentuais para o efeito do tipo 1 sobre os ovos de S. mansoni, sem contudo apresentar diferença significativa (p>0,01) entre eles. P. chlamydosporia demonstrou atividade ovicida sobre ovos de S. mansoni com resultados percentuais para os efeitos dos tipos 1, 2 e 3 apresentando um efeito do tipo 3 de 26,6% (VC1) e 17,2% (VC4); 25,6% (VC1) e 22,6% (VC4); 26,3% (VC1) e 23,0% (VC4) respectivamente aos sete, 14 e 21 dias. Contudo ao final do ensaio experimental B, também não foi observada diferença na ação entre os isolados VC1 e VC4 para os efeitos dos tipos 1, 2 e 3. Os resultados dos ensaios experimentais in vitro A e B demonstraram que P. chlamydosporia (VC1 e VC4) influenciou de forma negativa os ovos de F. hepatica e S. mansoni, e assim pode ser considerado como um potencial candidato a controlador biológico desses helmintos.

5'-Deoxy-5'-methylthioadenosine (MTA) is derived from s-adenosylmethionine (AdoMet) during the synthesis of the polyamines spermidine and spermine. Methionine can be regenerated from MTA by one of two mechanisms. In mammalian cells and some microorganisms, MTA is degraded to adenine and 5-methylthioribose-1-phosphate (MTR-1-P) via MTA phosphorylase. In certain other microbes, however, MTA is catabolized in two steps; first to adenine and 5-methylthioribose (MTR) via MTA nucleosidase followed by conversion of MTR to MTR-1-P via MTR kinase. This study was to demonstrate the presence of MTA nucleosidase or MTA phosphorylase in both redia containing cercariae and adult Fasciola hepatica Linnaeus, 1758. If MTA nucleosidase was present, it was wanted to determine if MTR kinase was also present. The phosphate-dependent cleaving activity of MTA phosphorylase was demonstrated in the cell-free extracts of adult Fasciola hepatica along with an unidentified MTR metabolizing activity. Redia containing cercariae showed MTA nucleosidase and MTR kinase activity.

The liver flukes Fasciola hepatica and F. gigantica cause infectious disease in ruminants and humans. The geographical range of these two parasite species (temperate and tropical respectively) ensures that infection can occur worldwide. Although anthelmintic treatment is effective against disease, emerging drug resistant strains leads to the development of a vaccine. However, despite several decades of research, there is no commercial vaccine available. The main challenge at present is to produce recombinant proteins in an immunologically active form using recombinant DNA technology. This is an essential step in Fasciola vaccine production. Cysteine proteases are probably the most important facilitators of virulence in flukes and are produced by all stages of the fluke life-cycle. Two classes of cysteine protease are found in the excretory and secretory material of liver flukes- these are cathepsin L and cathepsin B. As such, the major aims of this thesis were to investigate the expression and purification of Fasciola recombinant cysteine proteins, and characterisation by SDS-PAGE and immunoblotting using monoclonal and polyclonal antibodies. These studies demonstrate the production of functionally active cathepsin proteins in S. cerevisiae BJ3505 cells which will lead to vaccine candidate analysis. The second aim of this thesis was to determine the protective efficacy of stage specific target antigens against experimental infection. In addressing this issue, the protective efficacy of single and multivalent recombinant protein vaccinations of adult stage F. hepatica cathepsin L5, immature F. gigantica cathepsin L1g and juvenile F. hepatica cathepsin B were analysed in Sprague Dawley rats against F. hepatica infection. This study demonstrates that juvenile fluke target antigen-cathepsin B induces better immune protection than adult fluke antigen-cathepsin L5. Cocktails of juvenile and adult stage fluke recombinant proteins (cathepsin B and L5) elicited the highest protective immunity against experimental infection and this combination showed not only reduction in fluke recovery and size of flukes, but also marked diminution in the intensity of liver lesions in vaccinated rats. In order to assess the immunogenic property of an early infective stage fluke secreting cysteine protease as a vaccine candidate, DNA vaccination vectors encoding cathepsin B were analysed in BALB/c mice. In this study, the ability of four DNA vaccination strategies such as secretory, chemokine-activating, lymph node targeting vectors encoding cathepsin B were assessed by antibody titre, antibody avidity, western blotting and ELIPSOT assay. The results have further validated the immunoprophylactic potential of a cathepsin B vaccine against F. hepatica. In this study, we have expressed and attained high yields of F. gigantica cathepsin L1g from E. coli BL21, and compared this to a yeast-expressed system. This protease was over-expressed and formed insoluble inclusion bodies that were subsequently solubilised with urea or guanidine hydrochloride. In order to purify the urea-solubilised protein, step-wise urea gradient chromatography was used. For refolding of solubilised protein, a dilution and dialysis procedure was utilised. Proteolytic activity was confirmed by gelatin SDS-PAGE analysis. In conclusion, the determination of the immune potential of recombinant stage specific antigens allows the development of effective vaccines against Fasciola infection.

Schistosoma mansoni and Fasciola hepatica are parasitic trematodes which contain cytochrome c peroxidase (CcP) in their mitochondria, an enzyme that is absent in mammalian tissues. CcP reduces hydrogen peroxide to H2O using cytochrome c as the electron donor. Both parasites are catalase deficient; thus, cytochrome c peroxidase and glutathione peroxidase are the enzymes involved in the detoxification of H2O 2 in these organisms. The enzymatic activity of these two peroxidases may enable S. mansoni and F. hepatica to survive oxidative stress. The main objective of this study was to characterize cytochrome c peroxidase from S. mansoni and F. hepatica . Kinetic studies of this enzyme in crude homogenate and isolated mitochondria of S. mansoni were initially performed, followed by purification studies from S. mansoni and F. hepatica . The parasite enzyme has affinity for horse heart and yeast cytochrome c and it is inhibited by sodium azide and potassium cyanide. CcP was purified close to homogeneity and identified as a protein containing heme. The antioxidant capability of F. hepatica CcP was tested in vitro , demonstrating that CcP protected the sugar deoxyribose from oxidative degradation. Exposure of adult worms to H2O2 caused a decrease in S. mansoni CcP activity in vivo. An attempt was made to clone the S. mansoni CcP gene. The experiments did not result in the cloning of the CcP gene, but led to the identification and cloning of another protein, a component of a cytosolic chaperonin, t-complex polypeptide one (TCP-1). TCP-1 from S. mansoni is highly homologous to TCP-1 proteins from different organisms including, Chinese hamster, human, Drosophila and yeast and carries ATP binding amino acid motifs indicating that it has ATPase activity.

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Tereza Kněžíková Supervisor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: Liver fluke - treatment and resistence Fasciola hepatica is a parasite of global importance that we find both in farm animals and in humans. This thesis aims to summarize information on the potential of drugs and treatment alternatives that are suitable for treatment of F. hepatica. Given that for a number of drugs used in the past, as well as the drugs currently administered, resistance developed, this thesis is also focused on this phenomenon, especially the mechanisms of its origin. The drugs used to treat fasciolosis are called antitrematodal drugs. They can be divided into five chemical groups, of which the most important group are currently benzimidazoles and their representative triclabendazole. Also other drugs as albendazole, clorsulon, hexachlorophene, closantel, diamphenitide, bithionol, rafoxanide are important. The rate of resistance development is affected by many factors that may be genetic, biological or functional. F. hepatica actively uses its enzymatic system, especially oxidation enzymes or efflux transporters. The influence on the development of resistance, apart from the parasite itself,...