RESUMO

Recently, fish byproducts have been appraised as a source of structurally diverse bioactive compounds. In this context, fish mucus has revealed a myriad of pharmacological activities. This study describes a new bioactive molecule release system composed of protein nanoparticles from pacamã (Lophiosilurus alexandri) mucus, an endemic fish to the São Francisco River (Brazil). The process of obtaining and applying these nanoparticles, composed of proteins present in the pacamã mucus, as biocompatible carriers of bioactive molecules is also addressed herein. Therefore, the external mucus of the fish was collected, lyophilized and hydrated in deionized water containing the template molecule. After pH adjustment to 7.5, followed by sonication and centrifugation, the formed nanoparticles were collected in the supernatant. Additionally, the mucus and the particles were characterized, and pharmacological effects were evaluated regarding their antifungal, antibacterial, anticancer, anti or pro-inflammatory and antinociceptive proprieties. NP-Mucus did not exhibit antibacterial activity against Pseudomonas aeruginosa or Staphylococcus aureus. However, it showed potential effects against Candida albicans with a minimum inhibitory concentration (MIC) of 1 µg/mL, and significant pro-inflammatory role, reflected by cellular recruitment activity and healing effects. Therefore, future studies are now needed in order to identify specific compounds in NP-mucus responsible for the observed effects in order to provide new pharmacological and therapeutic strategies.

Recentemente, os subprodutos de peixes foram avaliados como uma fonte de compostos bioativos estruturalmente diversos. Nesse contexto, o muco dos peixes revelou uma miríade de atividades farmacológicas. Este estudo descreve um novo sistema de liberação de moléculas bioativas compostas por nanopartículas de proteínas do muco do pacamã (Lophiosilurus alexandri), um peixe do Rio São Francisco (Brasil). O processo de obtenção e aplicação dessas nanopartículas, compostas por proteínas presentes no muco do pacamã, como carreadores biocompatíveis de moléculas bioativas também são abordados neste artigo. Para tanto, o muco externo dos peixes foi coletado, liofilizado e hidratado em água deionizada contendo a molécula template. Após ajuste do pH para 7,5, seguido de sonicação e centrifugação, as nanopartículas formadas foram coletadas no sobrenadante. Adicionalmente, foram caracterizados o muco e as partículas, sendo avaliados os efeitos farmacológicos quanto às propriedades antifúngicas, antibacterianas, anticancerígenas, anti ou pró-inflamatórias e antinociceptivas. NP-Mucus não exibiu atividade antibacteriana contra Pseudomonas aeruginosa ou Staphylococcus aureus. No entanto, apresentou efeitos potenciais contra Candida albicans com concentração inibitória mínima (MIC) de 1 µg/mL, além de importante papel próinflamatório, refletido pela atividade de recrutamento celular e efeitos cicatrizantes. Portanto, estudos são necessários para identificar compostos no NP-muco responsáveis pelos efeitos observados, a fim de fornecer novas estratégias farmacológicas e terapêuticas.

Assuntos

RESUMO

Recently, fish byproducts have been appraised as a source of structurally diverse bioactive compounds. In this context, fish mucus has revealed a myriad of pharmacological activities. This study describes a new bioactive molecule release system composed of protein nanoparticles from pacamã (Lophiosilurus alexandri) mucus, an endemic fish to the São Francisco River (Brazil). The process of obtaining and applying these nanoparticles, composed of proteins present in the pacamã mucus, as biocompatible carriers of bioactive molecules is also addressed herein. Therefore, the external mucus of the fish was collected, lyophilized and hydrated in deionized water containing the template molecule. After pH adjustment to 7.5, followed by sonication and centrifugation, the formed nanoparticles were collected in the supernatant. Additionally, the mucus and the particles were characterized, and pharmacological effects were evaluated regarding their antifungal, antibacterial, anticancer, anti or pro-inflammatory and antinociceptive proprieties. NP-Mucus did not exhibit antibacterial activity against Pseudomonas aeruginosa or Staphylococcus aureus. However, it showed potential effects against Candida albicans with a minimum inhibitory concentration (MIC) of 1 µg/mL, and significant pro-inflammatory role, reflected by cellular recruitment activity and healing effects. Therefore, future studies a

RESUMO

Recently, fish byproducts have been appraised as a source of structurally diverse bioactive compounds. In this context, fish mucus has revealed a myriad of pharmacological activities. This study describes a new bioactive molecule release system composed of protein nanoparticles from pacamã (Lophiosilurus alexandri) mucus, an endemic fish to the São Francisco River (Brazil). The process of obtaining and applying these nanoparticles, composed of proteins present in the pacamã mucus, as biocompatible carriers of bioactive molecules is also addressed herein. Therefore, the external mucus of the fish was collected, lyophilized and hydrated in deionized water containing the template molecule. After pH adjustment to 7.5, followed by sonication and centrifugation, the formed nanoparticles were collected in the supernatant. Additionally, the mucus and the particles were characterized, and pharmacological effects were evaluated regarding their antifungal, antibacterial, anticancer, anti or pro-inflammatory and antinociceptive proprieties. NP-Mucus did not exhibit antibacterial activity against Pseudomonas aeruginosa or Staphylococcus aureus. However, it showed potential effects against Candida albicans with a minimum inhibitory concentration (MIC) of 1 µg/mL, and significant pro-inflammatory role, reflected by cellular recruitment activity and healing effects. Therefore, future studies are now needed in order to identify specific compounds in NP-mucus responsible for the observed effects in order to provide new pharmacological and therapeutic strategies.(AU)

Recentemente, os subprodutos de peixes foram avaliados como uma fonte de compostos bioativos estruturalmente diversos. Nesse contexto, o muco dos peixes revelou uma miríade de atividades farmacológicas. Este estudo descreve um novo sistema de liberação de moléculas bioativas compostas por nanopartículas de proteínas do muco do pacamã (Lophiosilurus alexandri), um peixe do Rio São Francisco (Brasil). O processo de obtenção e aplicação dessas nanopartículas, compostas por proteínas presentes no muco do pacamã, como carreadores biocompatíveis de moléculas bioativas também são abordados neste artigo. Para tanto, o muco externo dos peixes foi coletado, liofilizado e hidratado em água deionizada contendo a molécula template. Após ajuste do pH para 7,5, seguido de sonicação e centrifugação, as nanopartículas formadas foram coletadas no sobrenadante. Adicionalmente, foram caracterizados o muco e as partículas, sendo avaliados os efeitos farmacológicos quanto às propriedades antifúngicas, antibacterianas, anticancerígenas, anti ou pró-inflamatórias e antinociceptivas. NP-Mucus não exibiu atividade antibacteriana contra Pseudomonas aeruginosa ou Staphylococcus aureus. No entanto, apresentou efeitos potenciais contra Candida albicans com concentração inibitória mínima (MIC) de 1 µg/mL, além de importante papel próinflamatório, refletido pela atividade de recrutamento celular e efeitos cicatrizantes. Portanto, estudos são necessários para identificar compostos no NP-muco responsáveis pelos efeitos observados, a fim de fornecer novas estratégias farmacológicas e terapêuticas.(AU)

Assuntos

RESUMO

The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.(AU)

Os efeitos de secas extremas sobre peixes de água doce ainda é globalmente desconhecido. Neste artigo, nós estimamos o fator de condição, uma medida relativa de bem estar baseada na relação entre e peso do corpo e o comprimento, em quatro espécies de peixes de lagos da Amazônia, pertencentes a dois níveis tráficos (onívoros e carnívoros), capturadas durante três anos consecutivos: 2004, 2005 (quando ocorreu uma seca anômala) e 2006. As duas espécies onívoras, Colossoma macropomum e Mylossoma duriventre exibiram tendências consistentes com seu ciclo de vida nos anos de 2004 e 2006: valores mais altos na cheia, vazante e seca, seguida por uma queda na enchente que coincide com a estação reprodutiva. No entanto, o fator de condição foi muito menor durante a seca e a enchente em 2005, provavelmente devido a redução anormal na disponibilidade de recursos em um habitat reduzido. As duas espécies piscívoras, as piranhas Serrasalmus spilopleura e S. elongatus, mantiveram relativa estabilidade nas estimativas do fator d condição, ao longo do ciclo hidrológico dos três anos, sem efeito aparente da seca extrema, provavelmente porque a redução do habitat foi contrabalanceada pelo aumento na densidade de presas. Caso as predições de aumento de frequência de secas extremas venha a se confirmar, acreditamos que espécies predadoras poderão ser beneficiadas, ao menos no curto prazo, enquanto as onívoras serão negativamente afetadas.(AU)

Assuntos

RESUMO

Abstract The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.

Resumo Os efeitos de secas extremas sobre peixes de água doce ainda é globalmente desconhecido. Neste artigo, nós estimamos o fator de condição, uma medida relativa de bem estar baseada na relação entre e peso do corpo e o comprimento, em quatro espécies de peixes de lagos da Amazônia, pertencentes a dois níveis tróficos (onívoros e carnívoros), capturadas durante três anos consecutivos: 2004, 2005 (quando ocorreu uma seca anômala) e 2006. As duas espécies onívoras, Colossoma macropomum e Mylossoma duriventre exibiram tendências consistentes com seu ciclo de vida nos anos de 2004 e 2006: valores mais altos na cheia, vazante e seca, seguida por uma queda na enchente que coincide com a estação reprodutiva. No entanto, o fator de condição foi muito menor durante a seca e a enchente em 2005, provavelmente devido a redução anormal na disponibilidade de recursos em um habitat reduzido. As duas espécies piscívoras, as piranhas Serrasalmus spilopleura e S. elongatus, mantiveram relativa estabilidade nas estimativas do fator d condição, ao longo do ciclo hidrológico dos três anos, sem efeito aparente da seca extrema, provavelmente porque a redução do habitat foi contrabalanceada pelo aumento na densidade de presas. Caso as predições de aumento de frequência de secas extremas venha a se confirmar, acreditamos que espécies predadoras poderão ser beneficiadas, ao menos no curto prazo, enquanto as onívoras serão negativamente afetadas.

Assuntos

RESUMO

The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.

Assuntos

RESUMO

Abstract The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.

Resumo Os efeitos de secas extremas sobre peixes de água doce ainda é globalmente desconhecido. Neste artigo, nós estimamos o fator de condição, uma medida relativa de bem estar baseada na relação entre e peso do corpo e o comprimento, em quatro espécies de peixes de lagos da Amazônia, pertencentes a dois níveis tróficos (onívoros e carnívoros), capturadas durante três anos consecutivos: 2004, 2005 (quando ocorreu uma seca anômala) e 2006. As duas espécies onívoras, Colossoma macropomum e Mylossoma duriventre exibiram tendências consistentes com seu ciclo de vida nos anos de 2004 e 2006: valores mais altos na cheia, vazante e seca, seguida por uma queda na enchente que coincide com a estação reprodutiva. No entanto, o fator de condição foi muito menor durante a seca e a enchente em 2005, provavelmente devido a redução anormal na disponibilidade de recursos em um habitat reduzido. As duas espécies piscívoras, as piranhas Serrasalmus spilopleura e S. elongatus, mantiveram relativa estabilidade nas estimativas do fator d condição, ao longo do ciclo hidrológico dos três anos, sem efeito aparente da seca extrema, provavelmente porque a redução do habitat foi contrabalanceada pelo aumento na densidade de presas. Caso as predições de aumento de frequência de secas extremas venha a se confirmar, acreditamos que espécies predadoras poderão ser beneficiadas, ao menos no curto prazo, enquanto as onívoras serão negativamente afetadas.

RESUMO

Abstract The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.

Resumo Os efeitos de secas extremas sobre peixes de água doce ainda é globalmente desconhecido. Neste artigo, nós estimamos o fator de condição, uma medida relativa de bem estar baseada na relação entre e peso do corpo e o comprimento, em quatro espécies de peixes de lagos da Amazônia, pertencentes a dois níveis tróficos (onívoros e carnívoros), capturadas durante três anos consecutivos: 2004, 2005 (quando ocorreu uma seca anômala) e 2006. As duas espécies onívoras, Colossoma macropomum e Mylossoma duriventre exibiram tendências consistentes com seu ciclo de vida nos anos de 2004 e 2006: valores mais altos na cheia, vazante e seca, seguida por uma queda na enchente que coincide com a estação reprodutiva. No entanto, o fator de condição foi muito menor durante a seca e a enchente em 2005, provavelmente devido a redução anormal na disponibilidade de recursos em um habitat reduzido. As duas espécies piscívoras, as piranhas Serrasalmus spilopleura e S. elongatus, mantiveram relativa estabilidade nas estimativas do fator d condição, ao longo do ciclo hidrológico dos três anos, sem efeito aparente da seca extrema, provavelmente porque a redução do habitat foi contrabalanceada pelo aumento na densidade de presas. Caso as predições de aumento de frequência de secas extremas venha a se confirmar, acreditamos que espécies predadoras poderão ser beneficiadas, ao menos no curto prazo, enquanto as onívoras serão negativamente afetadas.

RESUMO

The subfamily Phyllomedusinae has attracted a great interest of many researchers mainly due to the high diversity of these frog species and plethora of pharmacological activities frequently observed for their skin secretions. Despite of this fact, mainly for new species, limited information is available regarding the molecular composition of these skin secretions and the cellular components involved in their production. Phyllomedusa nordestina is a recently described Brazilian frog species also popularly known as 'tree-frogs'. Aiming at contributing to the biological knowledge of this species, we show here the gene expression profile of this frog skin secretion using a global ESTs analysis of a cDNA library. The marked aspect of this analysis revealed a significant higher transcriptional level of the opioid peptide dermorphins in P. nordestina skin secretion than in Phyllomedusa hypochondrialis, which is its closest related species, belonging both to the same phylogenetic group. Precursors of bioactive peptides as dermaseptins, phylloseptins, tryptophyllins, and bradykinin-like peptideswere also found in this library. Transcripts encoding proteins related to ordinary cellular functions and pathways were also described. Some of them are chiefly involved in the production of the skin secretion. Taken together, the data reported here constitute a contribution to the characterization of the molecular diversity of gene-encoded polypeptides with potential possibility of pharmacological exploitation. The transcriptional composition of the skin secretion may also help to give the necessary support for the definition of P. nordestina as a new species, which actually relies basically on frog morphological characteristics and geographical distribution.

Assuntos

RESUMO

Considerable efforts are currently focused on the biology of DC in view of their possible clinical use as adjuvant for the generation of antigen-specific immunity and lifelong immunologic memory or for the treatment of tumors. We assessed the role of Nattectin a C-type lectin identified in the Thalassophryne nattereri fish venom in DC maturation. Nattectin induced a significant neutrophilic recruitment into peritoneal cavity of mice, followed by macrophages, with lipidic mediators and IL-12 p70 synthesis. Macrophages derived from 7 day-Nattectin mice were CD11c + CD11blowLy6 highF4/80Rhigh and express high levels of MHC class II and CD80 molecules. Culture of peritoneal exudates derived macrophages from 7 day Nattectin-mice and immature BMDCs with Nattectin markedly increased the surface expression of CD40, CD80, CD86, and MHC class II in a dose-dependent manner, and the production of MMP-2 and MMP-9 distributed in nucleus and cytoplasm of cells, that was associated with strong activity in the culture supernatant. Nattectin treated DCs secreted IL-12 p70 and IL-10. The Nattectin-treated BMDC or macrophage-derived DCs were highly efficient at Ag capture. The specific immune response elicited by Nattectin was characterized by the production of specific antibodies IgG1 and mainly IgG2a with IL-10 and IFN-ã synthesis by splenic cells. These results enable us to address that Nattectin induces the recruitment of Ly6Chigh monocytes into the peritoneum, which exhibit a pro-inflammatory profile, where they differentiate into proliferating F4/80Rhigh macrophages. Macrophage-derived DCs mature in the presence of the cytokine milieu generated against Nattectin, exhibiting T cell co-stimulatory molecule expression and induced a Th1 polarized response.

Assuntos