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1.
ACS Appl Mater Interfaces ; 13(34): 40415-40428, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470103

RESUMO

Toxoplasma gondii (T. gondii) infection causes severe zoonotic toxoplasmosis, which threatens the safety of almost one-third of the human population globally. However, there is no effective protective vaccine against human toxoplasmosis. This necessitates anti-T. gondii vaccine development, which is a main priority of public health. In this study, we optimized the adjuvant system 04 (AS04), a vaccine adjuvant constituted by 3-O-desacyl-4'-monophosphoryl lipid A (a TLR4 agonist) and aluminum salts, by packing it within natural extracts of ß-glucan particles (GPs) from Saccharomyces cerevisiae to form a GP-AS04 hybrid adjuvant system. Through a simple mixing procedure, we loaded GP-AS04 particles with the total extract (TE) of T. gondii lysate, forming a novel anti-T. gondii vaccine GP-AS04-TE. Results indicated that the hybrid adjuvant can efficiently and stably load antigens, mediate antigen delivery, facilitate the dendritic uptake of antigens, boost dendritic cell maturation and stimulation, and increase the secretion of pro-inflammatory cytokines. In the mouse inoculation model, GP-AS04-TE significantly stimulated the function of dendritic cells, induced a very strong TE-specific humoral and cellular immune response, and finally showed a strong and effective protection against toxoplasma chronic and acute infections. This work proves the potential of GP-AS04 for exploitation as a vaccine against a range of pathogens.


Assuntos
Adjuvantes de Vacinas/uso terapêutico , Hidróxido de Alumínio/uso terapêutico , Lipídeo A/análogos & derivados , Nanocompostos/uso terapêutico , Vacinas Protozoárias/uso terapêutico , Toxoplasma/imunologia , Toxoplasmose/prevenção & controle , Adjuvantes de Vacinas/química , Adjuvantes de Vacinas/toxicidade , Hidróxido de Alumínio/química , Hidróxido de Alumínio/imunologia , Hidróxido de Alumínio/toxicidade , Animais , Células Dendríticas/efeitos dos fármacos , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/uso terapêutico , Polissacarídeos Fúngicos/toxicidade , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Lipídeo A/química , Lipídeo A/imunologia , Lipídeo A/uso terapêutico , Lipídeo A/toxicidade , Masculino , Camundongos Endogâmicos C57BL , Nanocompostos/química , Nanocompostos/toxicidade , Fagócitos/efeitos dos fármacos , Vacinas Protozoárias/química , Vacinas Protozoárias/imunologia , Vacinas Protozoárias/toxicidade , Saccharomyces cerevisiae/química , Extratos de Tecidos/química , Extratos de Tecidos/imunologia , Extratos de Tecidos/uso terapêutico , Extratos de Tecidos/toxicidade , Toxoplasma/química , Toxoplasmose/imunologia , beta-Glucanas/química , beta-Glucanas/uso terapêutico , beta-Glucanas/toxicidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-33957353

RESUMO

Phorbas is a widely studied genus of marine sponge and produce structurally rich cytotoxic metabolites. Still, only few studies have assessed metabolites present in Brazilian species. To circumvent redundancy, in this work, we applied and herein report the use of a scouting liquid chromatographic system associate to the design of experiment produced by the DryLab® software to obtain a fast and efficient chromatographic separation of the active hexane fraction, further enabling untargeted high-resolution mass spectrometry (HRMS) data. To this end, a crude hydroalcoholic extract of the sponge Phorbas amaranthus collected in Brazilian coast was prepared and partitioned. The cytotoxicity of the crude extract and the fractions was evaluated using tumor cell culture models. Fragmentation pathways assembled from HRMS data allowed the annotation of 18 known Phorbas metabolites, while 17 metabolites were inferred based on Global Natural Product Social Molecular Networking (GNPS), matching with a further 29 metabolites annotated through molecular subnetwork. The workflow employed demonstrates that chromatographic method development can be accelerated by the use of automated scouting systems and DryLab®, which is useful for profiling natural product libraries, as well as data curation by molecular clusters and should be incorporated to the tools of natural product chemists.


Assuntos
Cromatografia Líquida/métodos , Poríferos , Extratos de Tecidos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células HCT116 , Humanos , Lisofosfolipídeos/química , Poríferos/química , Poríferos/metabolismo , Esteroides/análise , Esteroides/química , Terpenos/análise , Terpenos/química , Extratos de Tecidos/análise , Extratos de Tecidos/metabolismo , Extratos de Tecidos/toxicidade
3.
Int J Mol Sci ; 19(4)2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29614018

RESUMO

Colorectal cancer is the third most widely diagnosed cancer. Extracts from snails may modulate growth and development of colorectal cancer cells. The objective of this study was to determine the chemical composition of tissues derived from Helix aspersa Müller and red-ox properties of tissue extracts. Then, the influence of extracts and their fractions of different molecular weights on viability of Caco-2 cells was examined. Tissue lyophilisates contained antioxidants that could be important in the prevention of colorectal cancer. Moreover, we confirmed the presence of a wide array of compounds that might be used in treatment of this disease. The decrease of cell viability after the application of extracts from lyophilized mucus and foot tissues was affirmed. The effect of extract from mucus could be related to the content of some proteins and peptides, proper essential amino acids (EAA)/non-essential amino acids (NEAA) ratio, Met restriction and the presence of Cu, Ca, Zn, Se. The influence of the extract from foot tissues could be assigned additionally to the presence of eicosapentaenoic, α-linolenic, linoleic and γ-linolenic acids. The opposite effect was demonstrated by extract from lyophilized shells which increased cell viability. Further studies are needed to know whether dietary supplying of H. aspersa Müller tissues can be used as an approach in colorectal cancer management.


Assuntos
Antineoplásicos/toxicidade , Caramujos/química , Extratos de Tecidos/toxicidade , Animais , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Humanos
4.
Pak J Pharm Sci ; 31(1): 143-151, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29348096

RESUMO

Channa striatus (Haruan) is Malaysian freshwater fish that is traditionally used to treat ailments related to wound and also ulcers. The aimed of the present study was to determine the mechanisms of anti-ulcer activity of chloroform: methanol extract of C. striatus fillet (CMCS) in rats. The antiulcer profile of CMCS, given orally in the doses of 50, 250 and 500mg/kg, was assessed using the ethanol- and indomethacin-induced gastric ulcer models. The mechanisms of antiulcer of CMCS were determined as follows; i) the antisecretory activity of CMCS was measured using the pyloric ligation rat model, and; ii) the role of nitric oxide (NO) and sulfhydryl compounds in the modulation of CMCS antiulcer activity were determined by pre-treating the rats with L-NAME or NEM, respectively, followed by the pre-treatment of rats with CMCS before subjecting the animals to the ethanol-induced gastric ulcer model. From the results obtained, CMCS exerted significant (P<0.05) antiulcer activity in both models of gastric ulcer wherein the macroscopic and microscopic analysis of the stomach supported the antiulcer claim. With regard to its antisecretory effect, CMCS did not change the volume and pH, but reduce the total acidity only at the lower doses of the gastric juice. Moreover, CMCS demonstrated antiulcer activity was reversed by NEM, but not affected by L-NAME. In conclusion, CMCS shows antiulcer activity that is modulated via its cytoprotective, but not antisecretory effect, and in the presence of sulfhysryl compounds, but not NO.


Assuntos
Antiulcerosos/uso terapêutico , Clorofórmio/química , Metanol/química , Músculo Esquelético/química , Perciformes , Extratos de Tecidos/uso terapêutico , Animais , Antiulcerosos/isolamento & purificação , Antiulcerosos/toxicidade , Modelos Animais de Doenças , Masculino , Ratos Sprague-Dawley , Úlcera Gástrica/tratamento farmacológico , Extratos de Tecidos/isolamento & purificação , Extratos de Tecidos/toxicidade , Testes de Toxicidade Aguda
5.
Drug Chem Toxicol ; 41(1): 16-21, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28633597

RESUMO

Following intramuscular injections of 0.1 mL, 3 mg kg-1 BW-1(1/10 LD50) T-2 toxin (T-2), the tissue concentration of T-2 in shrimp was quantitatively detected using LC-MS/MS. The biological half-time (t1/2) of T-2 in blood was 40.47 ± 0.24 min. The highest number of intramuscular T-2 shrimp could tolerate when given at blood t1/2 intervals was 4. The shrimps which were injected 5 T-2 died. The T-2 toxin highest accumulation was 0.471 ± 0.012 ng g-1 BW-1. The effect of toxic shrimp muscle subjected to different processing conditions (high pressure, trifluoroacetic acid, acid and alkali digestions, artificial digestive juice [to simulate exposure to gastric and intestinal juices]) on mouse macrophage cells (RAW267.4) were evaluated by the MTT assay. The inhibition ratio of 2% muscle extract on RAW267.4 was 85.70 ± 2.63%. The immunocytotoxicity of muscle extracts to RAW264.7 was highest in muscle extracts subjected to physical and chemical digestion (high pressure > NaOH > trifluoroacetic acid > 0.02 M HCl > 0.2 M HCl > controls), and also artificial digestion (artificial intestinal juice > artificial gastric juice > N type intestinal juice > N type gastric liquid > controls). Results showed that high-pressure and artificial intestinal juice were most effective in the release of modified T-2 to free T-2 thus enhancing toxicity. These results can be interpreted as measurement of T-2 in food being of little value because of enhanced toxicity of T-2-contaminated food as they pass through the gastrointestinal tract.


Assuntos
Macrófagos/efeitos dos fármacos , Músculos/metabolismo , Penaeidae/metabolismo , Intoxicação por Frutos do Mar , Frutos do Mar/efeitos adversos , Toxina T-2/toxicidade , Extratos de Tecidos/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Digestão , Relação Dose-Resposta a Droga , Suco Gástrico/metabolismo , Meia-Vida , Injeções Intramusculares , Secreções Intestinais/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Medição de Risco , Toxina T-2/administração & dosagem , Toxina T-2/farmacocinética , Distribuição Tecidual
6.
J Helminthol ; 92(2): 244-249, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28349851

RESUMO

Cylindrospermopsis raciborskii (Woloszynska) is a photosynthetic cyanobacterium that can produce cytotoxic (cylindrospermopsin) and neurotoxic cyanotoxins (saxitoxins). In Brazil the strains of C. raciborskii are reported to produce only saxitoxins (STX) and their effect on fish parasites has not been tested to date. The fish Poecilia vivipara Bloch and Schneider is a common host for the trematode Pygidiopsis macrostomum Travassos off the coast of Rio de Janeiro, and this fish-parasite interaction is a model for behavioural and ecotoxicological studies. The aim of this work was to evaluate the motility of metacercariae of P. macrostomum from P. vivipara exposed to 40 mg l-1 and 400 mg l-1 of crude lyophilized extract of the cyanobacterium C. raciborskii (CYRF-01) for 48 h. The fish were separated into groups of ten individuals and, after exposure, five fish from each group were dissected for counting and checking the motility of metacercariae. The other five fish were dissected after 48 h in clean water. The detection and quantification of STX in the solutions of cyanobacteria, and the gills and guts of fish, were performed by an enzyme-linked immunosorbent assay. The crude extract of C. raciborskii caused temporary paralysis in metacercariae of P. macrostomum after exposure of fish to both concentrations, and the motility recovered after the fish were kept for 48 h in clean water. STX was detected in the guts and gills of all fish analysed, suggesting that this toxin is involved in the paralysis of metacercariae. This is the first report on the action of neurotoxins in metacercariae of fish.


Assuntos
Cylindrospermopsis/química , Metacercárias/efeitos dos fármacos , Saxitoxina/toxicidade , Extratos de Tecidos/toxicidade , Trematódeos/efeitos dos fármacos , Infecções por Trematódeos/parasitologia , Animais , Interações Hospedeiro-Parasita/efeitos dos fármacos , Movimento/efeitos dos fármacos , Neurotoxinas/farmacologia , Neurotoxinas/toxicidade , Poecilia/parasitologia , Saxitoxina/farmacologia , Extratos de Tecidos/química , Extratos de Tecidos/farmacologia , Trematódeos/fisiologia
7.
Toxicon ; 137: 158-167, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28789838

RESUMO

Pterois volitans/miles lionfish (adult and juvenile) dorsal spines and caudal fin extracts were compared in their general composition, enzymatic activities and hemolytic and cytotoxic effects on bovine aortic endothelial cells and murine myoblasts, to distinguish between the activities present in the venom and epidermal mucus. Intradermal and intramuscular injections were also administered in mice to determine in vivo effects. This work shows that crude venom of Caribbean species of lionfish, present in dorsal spines, induces several in vitro effects including hemolysis, weak cytotoxicity, proteolytic and hyaluronidase activities, whereas in vivo, it is not hemorrhagic nor myotoxic, but causes edema, plasma extravasation and a thrombotic-associated lesion on the skin. Some small differences were observed between adult and juvenile venomous secretions. Gelatinolytic activity of the epidermal mucus, the only activity found in caudal fin extracts, could contribute to the in vivo toxicity of the venom.


Assuntos
Venenos de Peixe/toxicidade , Perciformes , Extratos de Tecidos/toxicidade , Fatores Etários , Nadadeiras de Animais/química , Animais , Osso e Ossos/química , Bovinos , Linhagem Celular , Citotoxinas/toxicidade , Edema/induzido quimicamente , Venenos de Peixe/enzimologia , Hemólise , Humanos , Hialuronoglucosaminidase/metabolismo , Espécies Introduzidas , Camundongos , Muco/metabolismo , Proteólise , Coelhos , Pele/efeitos dos fármacos , Pele/patologia
8.
Rev Iberoam Micol ; 34(4): 220-224, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28830736

RESUMO

BACKGROUND: The consumption of wild mushrooms has increased in recent years. However, not all mushrooms are edible and some of them may cause poisoning. Therefore, their toxicity needs to be studied. Artemia franciscana is a crustacean used in toxicity tests including toxins of fungi. AIMS: To determine the percentage of inhibition and mortality produced by extracts of several basidiomycetes on the hatching of A. franciscana cysts. METHODS: Aqueous extracts were prepared from 15 species of mushrooms collected from Jalisco state, Mexico. Different concentrations of the extracts were assayed in order to test their toxicity. Potassium dichromate and artificial seawater were the positive and negative controls, respectively. The percentages of hatching and mortality of the cysts were evaluated. RESULTS: Inhibition of hatching greater than 80% in all the concentrations tested was found in 13 of the 15 species studied, in contrast to the positive control, which inhibited cyst hatching less than 50% in all cases. The highest percentage of mortality in the cysts was caused by the aqueous extracts of Amanita virosa, Leucopaxillus amarus, and Tylopilus violatinctus, and the lowest by Macrolepiota mastoidea. CONCLUSIONS: The brine shrimp bioassay appeared to be useful in the evaluation of the toxicity of several basidiomycetes, with the exception of Scleroderma texense, a mushroom considered poisonous, which showed no toxicity over A. franciscana.


Assuntos
Artemia/efeitos dos fármacos , Basidiomycota/química , Animais , Artemia/crescimento & desenvolvimento , Artemia/microbiologia , Bioensaio , México , Intoxicação Alimentar por Cogumelos , Óvulo/efeitos dos fármacos , Especificidade da Espécie , Extratos de Tecidos/toxicidade , Água
9.
Toxicon ; 137: 150-157, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28688807

RESUMO

This study compares the role of hepatic cytosolic glutathione transferases (cGST) isoforms of three different bivalve species to a Microcystis aeruginosa extract and purified MC-LR exposure (both at 150 µg MC-LR L-1) for 24 h. Characterization and alterations of the cytosolic GST activities in Mytilus galloprovincialis, Ruditapes philippinarum and Corbicula fluminea were measured using four class-specific substrates and changes in individual GST isoforms expression were achieved by a subsequent two-dimensional electrophoresis analysis. Evaluation of cGST activity basal levels using the four class-specific substrates denoted quantitative differences between the three bivalves. Purified MC-LR did not induce any significant response from bivalves. On the other hand, cell extracts caused significant alterations according to bivalves and substrates. Among the three bivalves, only R. philippinarum showed a significant induction of cGST activity using generic 1-chloro-2,4-dinitrobenzene (CDNB) substrate. However, no significant alterations were detected in these clams by cell extracts using the other specific substrates. In contrast, C. fluminea revealed significant induction of cGST activity when using 3,4-dichloronitrobenzene (DCNB) and ethacrynic acid (EA). In M. galloprovincialis, cell extracts promoted a significant decrease of cGST activity when using EA substrate. Altered protein expression was quantitatively detected upon exposure to cell extracts for one spot in R. philippinarum and another for C. fluminea, both upregulated (2.0 and 8.5-fold, respectively) and identified as a sigma1-class GST in the case of the first. The results showed that the three bivalves presented specific adaptive biotransformation responses to MCs and other cyanobacteria compounds supported by the modulation of distinct cGST classes.


Assuntos
Toxinas Bacterianas/toxicidade , Bivalves/efeitos dos fármacos , Glutationa Transferase/antagonistas & inibidores , Fígado/enzimologia , Microcistinas/toxicidade , Animais , Biotransformação , Bivalves/enzimologia , Isoenzimas/antagonistas & inibidores , Toxinas Marinhas , Microcystis , Proteômica , Extratos de Tecidos/toxicidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-27002718

RESUMO

Detecting marine biotoxins such as paralytic shellfish toxins (PSTs) is essential to ensuring the safety of seafood. The mouse bioassay is the internationally accepted method for monitoring PSTs, but technical and ethical issues have led to a search for new detection methods. The mouse neuroblastoma cell-based assay (Neuro-2a CBA) using ouabain and veratridine (O/V) has proven useful for the detection of PSTs. However, CBAs are sensitive to shellfish-associated matrix interferences. As the extraction method highly influences matrix interferences, this study compared three extraction protocols: Association of Official Analytical Chemists (AOAC) 2005.06, AOAC 2011.02 and an alternative liquid-liquid method. These methods were used to assess the matrix effect of extracts from four commercially important bivalve species (Chilean mussel, Magellan mussel, clam and Pacific oyster) in Neuro-2a CBA. Extracts from all three protocols caused a toxic effect in Neuro-2a cells (without O/V) when tested at a concentration of 25 mg of tissue-equivalent (TE) ml(-1). The greatest toxicity was obtained through the AOAC 2011.02 protocol, especially for the Chilean mussel and Pacific oyster extracts. Similar toxicity levels (less than 15%) were observed in all extracts at 3.1 mg TE ml(-1). When assessed in Neuro-2a CBA, AOAC 2005.06 extracts presented the lowest matrix interferences, while the highest interferences were observed for AOAC 2011.02 in Magellan mussel and clam extracts. Finally, the AOAC 2005.06 and alternative protocols were compared using Chilean mussel samples fortified with 40 and 80 µg STX per 100 g meat. The AOAC 2005.06 method demonstrated better results. In conclusion, the AOAC 2005.06 extracts exhibited the fewest interferences in the Neuro-2a CBA. Therefore, this extraction method should be considered for the implementation of Neuro-2a CBA as a high-throughput screening methodology for PST detection.


Assuntos
Bivalves/química , Matriz Extracelular/química , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Toxinas Marinhas/análise , Neurônios/efeitos dos fármacos , Frutos do Mar/análise , Alternativas aos Testes com Animais , Animais , Bivalves/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chile , Matriz Extracelular/metabolismo , Contaminação de Alimentos/prevenção & controle , Ensaios de Triagem em Larga Escala , Extração Líquido-Líquido , Toxinas Marinhas/biossíntese , Toxinas Marinhas/toxicidade , Camundongos , Neurônios/patologia , Reprodutibilidade dos Testes , Saxitoxina/análise , Saxitoxina/biossíntese , Saxitoxina/toxicidade , Frutos do Mar/efeitos adversos , Intoxicação por Frutos do Mar/etiologia , Intoxicação por Frutos do Mar/patologia , Intoxicação por Frutos do Mar/prevenção & controle , Especificidade da Espécie , Extratos de Tecidos/análise , Extratos de Tecidos/isolamento & purificação , Extratos de Tecidos/toxicidade
11.
Biomed Mater Eng ; 26(1-2): 19-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26484552

RESUMO

BACKGROUND: Vascular extracellular matrices (vECMs) have shown potential for small-diameter blood vessel tissue engineering applications. However, problems such as chemical instability and easy calcification are still remained. Chemical crosslinking using crosslinkers such as glutaraldehyde (GA) can improve mechanical properties and proteolysis resistance of vECMs, but leads to calcification and cytotoxicity. Procyanidins (PC) can crosslink ECMs with anti-calcification property and cytocompatibility, but the mechanical properties and chemical stability are unsatisfactory. OBJECTIVE: A novel co-crosslinking technique using PC and GA was developed, which combines the advantages of both PC and GA for enhancing mechanical properties and stability of vECMs with reduced calcification and cytotoxicity. METHODS: Fresh carotid were decellularized and then crosslinked by PC and subsequent GA for 6 h respectively. The mechanical properties, dynamic release of PC, enzymatic degradation, calcification and cytotoxicity of crosslinked samples were evaluated. RESULTS: The co-crosslinked vECMs showed enhanced tensile strength, chemical and biological stability, comparable anti-calcification property as compared to pure PC-crosslinked samples. Cytotoxicity assay showed that the co-crosslinked vECMs were cytocompatible for supporting the adhesion and proliferation of HUVECs. CONCLUSIONS: Co-crosslinking with PC and GA might be a useful method for preparation of vECM scaffolds with potential applications in small-diameter blood vessel tissue engineering.


Assuntos
Artérias Carótidas/química , Células Endoteliais/efeitos dos fármacos , Matriz Extracelular/química , Glutaral/química , Proantocianidinas/química , Extratos de Tecidos/toxicidade , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistema Livre de Células/química , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Módulo de Elasticidade , Células Endoteliais/patologia , Glutaral/toxicidade , Humanos , Teste de Materiais , Proantocianidinas/toxicidade , Resistência à Tração , Extratos de Tecidos/química
13.
Mar Pollut Bull ; 98(1-2): 295-300, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26165935

RESUMO

This study provides, for the first time, a baseline evaluation of dioxin-like biological activity in sediments and fish sampled in- and adjacent to anchorages along the Mediterranean and Red Sea coasts of Israel. It indicates the effect of past pollution, still present in the sediments of older Israeli harbors, with putative contribution of still existing sources of pollution. A commercial reporter gene bioassay was used to evaluate the biological activity of dioxin-like compounds extracted from the samples. HRGC/HRMS analysis of several samples contributed a profile of dioxin-like compounds in sediments and fish. The results point out 1,2,3,4,6,7,8-HeptaCDD, 2,3,4,6,7,8-HexaCDF, 1,2,3,4,6,7,8-HeptaCDF, РСВ-126 and РСВ-118 as major contributors to the dioxin-like activity in sediments. It indicates polychlorinated biphenyls non-selective absorption in fish livers, in contrary to a biased accumulation of poorly chlorinated and more potent dibenzodioxins and dibenzofurans.


Assuntos
Bioensaio/métodos , Dioxinas/toxicidade , Peixes , Sedimentos Geológicos/análise , Fígado/química , Poluentes Químicos da Água/análise , Animais , Benzofuranos/farmacocinética , Benzofuranos/toxicidade , Dioxinas/farmacocinética , Monitoramento Ambiental , Genes Reporter , Sedimentos Geológicos/química , Oceano Índico , Israel , Mar Mediterrâneo , Bifenilos Policlorados/análise , Bifenilos Policlorados/farmacocinética , Bifenilos Policlorados/toxicidade , Extratos de Tecidos/análise , Extratos de Tecidos/química , Extratos de Tecidos/toxicidade , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade
14.
Pharm Biol ; 53(2): 286-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25243872

RESUMO

CONTEXT: Consumption of Sarpa salpa Linn. (Sparidae) in certain periods of the year is inadvisable because it can cause central nervous system disorders resulting in sea food poisoning. AIMS: The present study assesses the cytotoxic effects of compounds, not-yet identified, present in the organ extracts of S. salpa, collected in autumn, the period corresponding to the peak in human health problems. MATERIALS AND METHODS: The toxicity was assessed by mouse bioassay of aqueous extract of the fish organs. Wistar rats received daily extracts of different organs of S. salpa by gastric gavage for 7 d (0.3 mL of extract/100 g body weight BW). The dose of tissue extracts of viscera, liver, brain, and flesh of S. salpa administered to rats was as follows: 172, 313, 2050, and 2660 mg/kg BW, respectively. No deaths occurred during the period of treatment. RESULTS: The lethal dose (LD50) determined for the crude ciguatoxin (neurotoxins) extracts of viscera, liver, brain, and flesh of S. salpa was as follows: 1.2, 2.2, 14.4, and 18.6 g/kg mouse, respectively. Changes in locomotor activity during the first 2 h and failure in breathing and no evident signs of gastrointestinal problems were recorded. We observed (1) induction of oxidative stress, indicated by an increase in lipid peroxidation (TBARS) in groups that received extracts of liver (+425%) or viscera (+433%), and a significant decrease in antioxidant enzyme activities (SOD, CAT, and GPx) in cerebral cortex tissue by 13%, 25%, and 25% (LT: animals receiving liver extracts) and by 16%, 26%, and 27% (VT: animals receiving viscera extracts), respectively. In contrast, the administration of extracts of flesh and brain induced an increase in antioxidant enzyme activities (SOD, CAT, and GPx) in cerebral cortex tissue by 26%, 23%, and 44% (FT: flesh extract) and 28%, 24%, and 46% (BT: brain extract), respectively; (2) a significant decrease for acetylcholinesterase (AChE) activity in cerebral cortex was recorded in FT, BT, LT, and VT by 27, 34, 58, and 78%, respectively. Moreover, a significant decrease of AChE activity in plasma was recorded in FT, BT, LT, and VT by 16, 21, 38, and 48%, respectively; (3) the histological findings confirmed the biochemical results. CONCLUSIONS: Liver and especially the visceral part of S. salpa presented toxicity, which clearly indicates the danger of using this fish as food.


Assuntos
Peixes Venenosos , Síndromes Neurotóxicas/etiologia , Extratos de Tecidos/toxicidade , Acetilcolinesterase/sangue , Acetilcolinesterase/metabolismo , Administração Oral , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Injeções Intraperitoneais , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Tamanho do Órgão/efeitos dos fármacos , Ratos Wistar , Extratos de Tecidos/farmacocinética
15.
J Vet Med Sci ; 76(11): 1523-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25213205

RESUMO

The mouse bioassay (MBA) for paralytic shellfish poisoning (PSP) toxins has been used in the AOAC Official Method and the official Japanese method. In the AOAC Official Method, the saxitoxin (STX) standard provided by the U.S. Food and Drug Administration (FDA) is used, but no standard is used in the official Japanese method. The objective of this study was to compare the toxicity of decarbamoyl STX (dcSTX), one of the derivatives of STX and a candidate standard for the MBA for PSP toxins in Japan, to that of FDA STX in the MBA platform. In this study, the toxicity of dcSTX was 918.0 ± 44.9 mouse units/µmol, and the relative toxicity ratio of dcSTX to FDA STX based on moles was 0.478.


Assuntos
Bioensaio/normas , Saxitoxina/análogos & derivados , Saxitoxina/toxicidade , Intoxicação por Frutos do Mar/diagnóstico , Frutos do Mar/análise , Extratos de Tecidos/toxicidade , Animais , Bioensaio/métodos , Japão , Camundongos , Padrões de Referência , Organismos Livres de Patógenos Específicos
16.
Biol Res ; 47: 17, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-25027663

RESUMO

BACKGROUND: Black widow spider (L. tredecimguttatus) has toxic components not only in the venomous glands, but also in other parts of the body and its eggs. It is biologically important to investigate the molecular basis of the egg toxicity. RESULTS: In the present work, an aqueous extract was prepared from the eggs of the spider and characterized using multiple physiological and biochemical strategies. Gel electrophoresis and mass spectrometry demonstrated that the eggs are rich in high-molecular-mass proteins and the peptides below 5 kDa. The lyophilized extract of the eggs had a protein content of 34.22% and was shown to have a strong toxicity towards mammals and insects. When applied at a concentration of 0.25 mg/mL, the extract could completely block the neuromuscular transmission in mouse isolated phrenic nerve-hemidiaphragm preparations within 12.0 ± 1.5 min. Using whole-cell patch-clamp technique, the egg extract was demonstrated to be able to inhibit the voltage-activated Na+, K+ and Ca2+ currents in rat DRG neurons. In addition, the extract displayed activities of multiple hydrolases. Finally, the molecular basis of the egg toxicity was discussed. CONCLUSIONS: The eggs of black widow spiders are rich in proteinous compounds particularly the high-molecular-mass proteins with different types of biological activity The neurotoxic and other active compounds in the eggs are believed to play important roles in the eggs' toxic actions.


Assuntos
Proteínas de Artrópodes/toxicidade , Viúva Negra/química , Óvulo/química , Extratos de Tecidos/química , Exoesqueleto/química , Exoesqueleto/fisiologia , Animais , Proteínas de Artrópodes/isolamento & purificação , Canais de Cálcio/efeitos dos fármacos , Baratas/efeitos dos fármacos , Gânglios Espinais/efeitos dos fármacos , Camundongos , Óvulo/fisiologia , Nervo Frênico/efeitos dos fármacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , Ratos , Extratos de Tecidos/toxicidade , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos
18.
Food Chem Toxicol ; 70: 26-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24755394

RESUMO

Shark cartilage products are marketed as dietary supplements with claimed health benefits for animal and human use. Shark fin and cartilage products sold as extracts, dry powders and in capsules are marketed based on traditional Chinese medicine claims that it nourishes the blood, enhances appetite, and energizes multiple internal organs. Shark cartilage contains a mixture of chondroitin and glucosamine, a popular nutritional supplement ingested to improve cartilage function. Sharks are long-lived apex predators, that bioaccumulate environmental marine toxins and methylmercury from dietary exposures. We recently reported detection of the cyanobacterial toxin ß-N-methylamino-l-alanine (BMAA) in the fins of seven different species of sharks from South Florida coastal waters. Since BMAA has been linked to degenerative brain diseases, the consumption of shark products may pose a human risk for BMAA exposures. In this report, we tested sixteen commercial shark cartilage supplements for BMAA by high performance liquid chromatography (HPLC-FD) with fluorescence detection and ultra performance liquid chromatography/mass spectrometry/mass spectrometry (UPLC-MS/MS). Total mercury (Hg) levels were measured in the same shark cartilage products by cold vapor atomic fluorescence spectrometry (CVAFS). We report here that BMAA was detected in fifteen out of sixteen products with concentrations ranging from 86 to 265µg/g (dry weight). All of the shark fin products contained low concentrations of Hg. While Hg contamination is a known risk, the results of the present study demonstrate that shark cartilage products also may contain the neurotoxin BMAA. Although the neurotoxic potential of dietary exposure to BMAA is currently unknown, the results demonstrate that shark cartilage products may contain two environmental neurotoxins that have synergistic toxicities.


Assuntos
Diamino Aminoácidos/toxicidade , Suplementos Nutricionais , Contaminação de Medicamentos , Mercúrio/toxicidade , Neurotoxinas/toxicidade , Extratos de Tecidos/toxicidade , Diamino Aminoácidos/análise , Toxinas Bacterianas/toxicidade , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cianobactérias/química , Toxinas de Cianobactérias , Meio Ambiente , Toxinas Marinhas/toxicidade , Mercúrio/análise , Microcistinas/toxicidade , Neurotoxinas/análise , Espectrometria de Massas em Tandem , Extratos de Tecidos/química
19.
J Biochem Mol Toxicol ; 28(5): 198-205, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24616210

RESUMO

The early research found that the spiderlings of black widow spider (Latrodectus tredecimguttatus) exhibited obvious toxicity to animals. The present work performed a systematical analysis of the aqueous extract of newborn black widow spiderlings. The extract was shown to contain 69.42% of proteins varying in molecular weights and isoelectric points. Abdominal injection of the extract into mice and cockroaches caused obvious poisoning symptoms as well as death, with LD50 being 5.30 mg/kg in mice and 16.74 µg/g in Periplaneta americana. Electrophysiological experiments indicated that the extract at a concentration of 10 µg/mL could completely block the neuromuscular transmission in isolated mouse nerve-hemidiaphragm preparations within 21 ± 1.5 min, and 100 µg/mL extract could inhibit a certain percentage of voltage-activated Na⁺, K⁺, and Ca²âº channel currents in rat dorsal root ganglion neurons. These results demonstrate that the spiderlings are rich in neurotoxic components, which play important roles in the spiderling toxicity.


Assuntos
Viúva Negra , Neurotoxinas/toxicidade , Extratos de Tecidos/toxicidade , Animais , Viúva Negra/química , Viúva Negra/crescimento & desenvolvimento , Viúva Negra/fisiologia , Diafragma/efeitos dos fármacos , Diafragma/inervação , Eletroforese em Gel de Poliacrilamida , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Técnicas In Vitro , Canais Iônicos/antagonistas & inibidores , Dose Letal Mediana , Masculino , Camundongos Endogâmicos , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotoxinas/isolamento & purificação , Periplaneta , Transmissão Sináptica/efeitos dos fármacos , Extratos de Tecidos/isolamento & purificação
20.
Wei Sheng Yan Jiu ; 43(6): 944-52, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25603604

RESUMO

OBJECTIVE: The roasted fish fillet sample at the retail collected in Beijing and Qingdao were detected for TTX, and the TTX positive samples was analyzed for fish species identification. METHODS: TTX was tested by EUSA method and the cytochrome c oxidase I (COI) genome of TTX-positive samples was extracted and identified by DNA barcode. RESULTS: Totally, 90 samples were tested by EUSA and 58 (64.4%) samples were positive for TTX with the levels ranging from 0.10 mg/kg to 63.81 mg/kg. Among the TTX positive samples, 24 (41.3%) were identified containing toxic puffer fish and 21 (87.5%) were Lagocephalus lunaris, the highly toxic puffer fish. CONCLUSION: Some roasted fish fillet samples obtained from the retail in two cities were positive for TTX and contained toxic puffer fish. Based on these results, we suggest that roasted fish fillet producers should prevent toxic puffer fish from mixing in the raw material and the I regulators should strengthen the TTX surveillance and product labeling supervision of roasted fish fillet.


Assuntos
Venenos/análise , Tetraodontiformes/metabolismo , Tetrodotoxina/toxicidade , Extratos de Tecidos/análise , Animais , Comércio , DNA , Produtos Pesqueiros/envenenamento , Venenos/toxicidade , Reação em Cadeia da Polimerase , Tetraodontiformes/classificação , Tetrodotoxina/genética , Extratos de Tecidos/toxicidade
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