RESUMO

Schistosomiasis is a severely neglected disease with a wide geographical distribution. It affectsapproximately 210 million people in the world and at least 800 million people live in risk areas.The search for new drugs to treat this parasitosis is significant due to the appearance of strains of theworm that are resistant to the currently available drugs. The retrieval of compounds extracted fromplants that act on these parasites has increased scientific investigation of this subject. The presentstudy demonstrates, in vitro and in vivo, the action of crude extract of Piper tuberculatum on adultSchistosoma mansoni. The extract was shown to be quite effective in the in vitro tests, causing softtissue alterations and acting on the reproductive system of females and the mortality of the worms,with a greater effect on males. The in vivo experiment was performed with infected Mus musculusand a decrease in the number of eggs in the first and second oogram stages was found, suggestingaction on oviposition...

A esquistossomose, doença negligenciada grave e de larga distribuição geográfica, atinge cerca de210 milhões de pessoas no mundo e ao menos 800 milhões vivem em área de risco. A busca de novosmedicamentos para o tratamento desta parasitose é relevante em razão do aparecimento de linhagensdo verme resistentes aos fármacos disponíveis. A obtenção de compostos extraídos de plantas comação sobre parasitos tem incrementado a investigação científica sobre este assunto. O presentetrabalho mostra a ação in vitro e in vivo do extrato bruto de Piper tuberculatum sobre adultosde Schistosoma mansoni. O extrato mostrou-se bastante eficaz nos ensaios in vitro, provocandoalterações tegumentares, tendo ação no sistema reprodutor das fêmeas e na mortalidade dos vermes com maior ação sobre os machos. Como resultado em experimentos in vivo, realizados em Musmusculus infectados, observou-se a diminuição do número de ovos de 1º e 2º estágios em oogramas,o que sugere uma ação na postura de ovos...

Assuntos

RESUMO

This study aimed to carry out malacological samples of limnic mollusks present in a commercial fishing pond area on Itapecerica da Serra, São Paulo/Brazil, between July 2006 to June 2007. Furthermore, parasitological studies were also performed on specimens found. A total of 19,863 limnic mollusks were collected, represented by six species: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 and Anodontites trapesialis Lamarck, 1819, being this the first report of the occurrence of this species in fish and pay systems of Itapecerica da Serra. The parasitological examinations performed in 5,766 mollusks were negative, however, the greatest abundance of B. straminea, intermediate host of Schistosoma mansoni Sambon, 1907, becomes a concern. Thus, the need for increasing the malacological surveillance in the region due to the diversity of hydric collections in the municipality that has precarious sanitation conditions, high migration flow and the presence of imported and autochthonous cases of schistosomiasis.

Este trabalho teve como objetivo realizar levantamento da malacofauna límnica encontrada na área de um pesqueiro em Itapecerica da Serra, São Paulo - Brasil, no período de julho de 2006 a junho de 2007. Como complementação, foram feitos estudos parasitológicos em parte dos moluscos amostrados. Foram coletados 19.863 moluscos límnicos, representados por seis espécies: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 e Anodontites trapesialis Lamarck, 1819. Este pode ser considerado o primeiro relato da ocorrência dessas espécies em pesqueiros de Itapecerica da Serra. Os exames parasitológicos realizados em 5.766 moluscos foram negativos, no entanto, a presença de B. straminea, hospedeiro intermediário do Schistosoma mansoni Sambon, 1907 é preocupante. Diante disso, é necessário intensificar a vigilância malacológica na região devido à diversidade de coleções hídricas do município, precárias condições de saneamento básico, alto fluxo migratório de pessoas e o relato de casos importados e autóctones de esquistossomose.

Assuntos

RESUMO

This study aimed to carry out malacological samples of limnic mollusks present in a commercial fishing pond area on Itapecerica da Serra, São Paulo/Brazil, between July 2006 to June 2007. Furthermore, parasitological studies were also performed on specimens found. A total of 19,863 limnic mollusks were collected, represented by six species: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 and Anodontites trapesialis Lamarck, 1819, being this the first report of the occurrence of this species in fish and pay systems of Itapecerica da Serra. The parasitological examinations performed in 5,766 mollusks were negative, however, the greatest abundance of B. straminea, intermediate host of Schistosoma mansoni Sambon, 1907, becomes a concern. Thus, the need for increasing the malacological surveillance in the region due to the diversity of hydric collections in the municipality that has precarious sanitation conditions, high migration flow and the presence of imported and autochthonous cases of schistosomiasis.

Este trabalho teve como objetivo realizar levantamento da malacofauna límnica encontrada na área de um pesqueiro em Itapecerica da Serra, São Paulo - Brasil, no período de julho de 2006 a junho de 2007. Como complementação, foram feitos estudos parasitológicos em parte dos moluscos amostrados. Foram coletados 19.863 moluscos límnicos, representados por seis espécies: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 e Anodontites trapesialis Lamarck, 1819. Este pode ser considerado o primeiro relato da ocorrência dessas espécies em pesqueiros de Itapecerica da Serra. Os exames parasitológicos realizados em 5.766 moluscos foram negativos, no entanto, a presença de B. straminea, hospedeiro intermediário do Schistosoma mansoni Sambon, 1907 é preocupante. Diante disso, é necessário intensificar a vigilância malacológica na região devido à diversidade de coleções hídricas do município, precárias condições de saneamento básico, alto fluxo migratório de pessoas e o relato de casos importados e autóctones de esquistossomose.

RESUMO

Schistosomiasis is a neglected tropical disease that remains a considerable public health problem worldwide. Since the mainstay of schistosomiasis control is chemotherapy with a single drug,praziquantel, drug resistance is a concern. Here, we examined the in vitro effects of dermaseptin 01(DS 01), an antimicrobial peptide found in the skin secretion of frogs of the genus Phyllomedusa, onSchistosoma mansoni adult worms. DS 01 at a concentration of 100 mg/ml reduced the worm motor activity and caused the death of all worms within 48 h in RPMI 1640 medium. At the highest sublethal concentration of antimicrobial peptide (75 mg/ml), a 100% reduction in egg output of paired female worms was observed. Additionally, DS 01 induced morphological alterations on the tegument of S. mansoni, and a quantitative analysis carried out by confocal microscopy revealed extensive destruction of the tubercles in a dose-dependent manner over the concentration range of 50 –200 mg/ml. It was the first time that an anthelmintic activity towards schistosomes has been reported for a dermaseptin.

Assuntos

RESUMO

Schistosomiasis is a neglected tropical disease that remains a considerable public health problem worldwide. Since the mainstay of schistosomiasis control is chemotherapy with a single drug, praziquantel, drug resistance is a concern. Here, we examined the in vitro effects of dermaseptin 01 (DS 01), an antimicrobial peptide found in the skin secretion of frogs of the genus Phyllomedusa, on Schistosoma mansoni adult worms. DS 01 at a concentration of 100 µg/ml reduced the worm motor activity and caused the death of all worms within 48 h in RPMI 1640 medium. At the highest sublethal concentration of antimicrobial peptide (75 µg/ml), a 100% reduction in egg output of paired female worms was observed. Additionally, DS 01 induced morphological alterations on the tegument of S. mansoni, and a quantitative analysis carried out by confocal microscopy revealed extensive destruction of the tubercles in a dose-dependent manner over the concentration range of 50-200 µg/ml. It was the first time that an anthelmintic activity towards schistosomes has been reported for a dermaseptin.

Assuntos

RESUMO

Schistosomiasis affects more than 200 million people worldwide; another 600 million are at risk of infection. The schistosomulum stage is believed to be the target of protective immunity in the attenuated cercaria vaccine model. In an attempt to identify genes up-regulated in the schistosomulum stage in relation to cercaria, we explored the Schistosoma mansoni transcriptome by looking at the relative frequency of reads in EST libraries from both stages. The 400 genes potentially up-regulated in schistosomula were analyzed as to their Gene Ontology categorization, and we have focused on those encoding-predicted proteins with no similarity to proteins of other organisms, assuming they could be parasite-specific proteins important for survival in the host. Up-regulation in schistosomulum relative to cercaria was validated with real-time reverse transcription polymerase chain reaction (RT-PCR) for five out of nine selected genes (56%). We tested their protective potential in mice through immunization with DNA vaccines followed by a parasite challenge. Worm burden reductions of 16-17% were observed for one of them, indicating its protective potential. Our results demonstrate the value and caveats of using stage-associated frequency of ESTs as an indication of differential expression coupled to DNA vaccine screening in the identification of novel proteins to be further investigated as potential vaccine candidates.

Assuntos

RESUMO

Schistosomiasis is one of the world's greatly neglected tropical diseases, and its control is largely dependent on a single drug, praziquantel. Here, we report the in vitro effect of piplartine, an amide isolated from Piper tuberculatum (Piperaceae), on Schistosoma mansoni adult worms. A piplartine concentration of 15.8 µM reduced the motor activity of worms and caused their death within 24h in a RPMI 1640 medium. Similarly, the highest sub-lethal concentration of piplartine (6.3 µM) caused a 75% reduction in egg production in spite of coupling. Additionally, piplartine induced morphological changes on the tegument, and a quantitative analysis carried out by confocal microscopy revealed an extensive tegumental destruction and damage in the tubercles. This damage was dose-dependent in the range of 15.8-630.2 µM. At doses higher than 157.6 µM, piplartine induced morphological changes in the oral and ventral sucker regions of the worms. It is the first time that the schistosomicidal activity has been reported for piplartine.

Assuntos

RESUMO

Developing a vaccine against schistosomiasis would be an important advance on the control of this chronic and debilitating disease that afflicts millions of people worldwide. Herein we describe the use of the non-toxic B subunit of cholera toxin (CTB) genetically fused to Sm14 - a fatty-acid binding protein from Schistosoma mansoni - as an attempt to elicit a mucosal immune response against the lung stage of this parasite by intranasal immunization. Recombinant proteins were expressed on a prokaryotic system, purified by affinity chromatography and both immunochemically and spectroscopically characterized. Intranasal immunization experiments were performed on BALB/c mice and vaccine efficacy was assessed analyzing the worm-burden after challenge infection with S. mansoni cercariae. The results demonstrate that Sm14 itself was not able to reduce the worm burden on intranasally vaccinated animals. The presence of CTB – either in intranasal coadministration with or genetically fused to Sm14 – did not significantly improve the protective response of Sm14 as a worm burden reduction of only 20% could be observed. In addition to that, however, CTB demonstrated a clear anti inflammatory effect on the liver of immunized mice, which displayed hepatic granulomas around trapped eggs 15% smaller than control groups, indicating that CTB displays an immunomodulatory effect on the inflammatory responses induced by the parasite egg toxins.

Assuntos

RESUMO

Schistosomiasis is one of the world’s greatly neglected tropical diseases, and its control is largely dependenton a single drug, praziquantel. Here, we report the in vitro effect of piplartine, an amide isolated from Piper tuberculatum (Piperaceae), on Schistosoma mansoni adult worms. A piplartine concentrationof 15.8 lM reduced the motor activity of worms and caused their death within 24 h in a RPMI 1640 medium.Similarly, the highest sub-lethal concentration of piplartine (6.3 lM) caused a 75% reduction in eggproduction in spite of coupling. Additionally, piplartine induced morphological changes on the tegument,and a quantitative analysis carried out by confocal microscopy revealed an extensive tegumental destructionand damage in the tubercles. This damage was dose-dependent in the range of 15.8–630.2 lM. At doses higher than 157.6 lM, piplartine induced morphological changes in the oral and ventral sucker regions of the worms. It is the first time that the schistosomicidal activity has been reported forpiplartine.

Assuntos

RESUMO

Schistosomiasis affects more than 200 million people worldwide; another 600 million are at risk ofinfection. The schistosomulum stage is believed to be the target of protective immunity in the attenuated cercaria vaccine model. In an attempt to identify genes upregulated in the schistosomulum stage in relation to cercaria, we explored the Schistosoma mansoni transcriptome by looking at the relative frequency of reads in EST libraries from both stages. The 400 genes potentially up-regulated in schistosomula were analyzed as to their Gene Ontology categorization, and we have focused on those encoding-predicted proteins with no similarity to proteins of other organisms, assuming they could be parasite-specific proteins important for survival in the host. Up-regulation in schistosomulum relative to cercaria was validated with real-time reverse transcription polymerase chain reaction (RT-PCR) for five out of nine selected genes (56%). We tested their protective potential in mice through immunization with DNA vaccines followed by a parasite challenge. Worm burden reductions of 16–17% were observed for one of them, indicating its protective potential. Our results demonstrate the value and caveats of using stage-associated frequency of ESTs as na indication of differential expression coupled to DNA vaccine screening in the identification of novel proteins to be further investigated as potential vaccine candidates.

Assuntos